Brittney Dawney

Joshua M Pearce
email: pearce@mtu.edu

Optimizing the Solar Water Disinfection (SODIS) Method by Decreasing Turbidity with NaCl

Keywords: clay, drinking water, flocculation, sanitation, SODIS, sodium, turbidity

Solar water disinfection (SODIS) has proven to be effective at reducing diarrheal incidence in epidemiological intervention studies. However, the SODIS method is limited to waters of low turbidity (<30NTU). This study investigates the use of common table salt (NaCl) to reduce the turbidity of water containing suspended colloidal clay particles for use in the SODIS method. Three representative clays found in tropical soils (kaolinite, illite, and bentonite) were tested at three levels of turbidity (50, 100, and 200 NTU) for their flocculating behaviour with multiple NaCl concentrations to find the optimum. Supernatants were tested for sodium concentration for comparison against health and taste thresholds. Results show that unlike kaolinite and illite, pure bentonite solutions were shown to be very responsive to NaCl and produced supernatants with as low as 4 NTU (98% particle removal efficiency). This study has shown that NaCl, in combination with high-activity clay particles in solution, may effectively reduce turbidity to levels suitable for SODIS treatment, thereby expanding the number of people who can utilize the technology effectively.

Introduction

The overwhelming number of people without adequate access to clean water for drinking and sanitation purposes calls for the provision of an appropriate method of treating microbiologically contaminated water (World Health Organization 2010). Solar water disinfection (SODIS) has been proven in both bench and field scale trials to significantly reduce microbial content in contaminated water, and associated incidence of diarrhea in users (Centre for Disease Control 2008; [START_REF] Graf | Health gains from solar water disinfection (SODIS): evaluation of a water quality intervention in Yaoundé, Cameroon[END_REF]Meierhofer 2006;World Health Organization 2002). However, the technology is limited to relatively clear water (with turbidity less than 30 nephalometric turbidity units [NTU]); therefore, there is significant need to provide a practical method of reducing turbidity in water prior to solar disinfection.

This study investigates the use of a common reagent, table salt (NaCl), in facilitating the settling of colloidal clay particles in water, with the aim of expanding the availability of the SODIS technology. First, the SODIS method is reviewed along with the effects of turbidity, colloidal particles and sodium content. Then, three representative clays found in tropical soils (kaolinite, illite, and bentonite [sodium form]) were tested at three levels of turbidity (50,100,and 200 NTU) for their flocculating behaviour with five concentrations (0.001 M, 0.005 M, 0.01 M, 0.05 M, and 0.1 M) of NaCl. The supernatant was tested for remaining sodium concentration for comparison against health and taste thresholds. The results are then reviewed, discussed and conclusions are drawn about the viability of NaCl in reducing turbidity in waters containing colloidal clay particles.

Background

Solar Water Disinfection

Although specialized methods are needed to appropriately purify chemical contamination of drinking water supplies in poor regions [START_REF] Hashmi | Viability of Small-Scale Arsenic-Contaminated Water Purification Technologies for Sustainable Development in Pakistan[END_REF], one of the most technically simple, affordable, and practical systems for disinfecting microbiologicallycontaminated water is the solar water disinfection (SODIS) system (World Health Organization 2002). This system treats contaminated water by inactivating microorganisms through a synergistic combination of optical and thermal processes and requires only a transparent container [START_REF] Meierhofer | Solar water disinfection: A guide for the application of SODIS[END_REF]. As it employs pointof-use treatment, the clean water can be used and stored with a reduced risk of secondary contamination. Furthermore, at an annual cost of US$0.40-US$3.00, depending on location, it is an extremely low-cost water treatment method (Meierhofer & Landolt 2008;World Health Organization 2002) and is one of the most inexpensive household treatments available (Clasen et al. 2007).

The inactivation of select bacteria, viruses, and protozoa due to UV-A radiation and heat has been studied extensively in studies under both simulated and natural conditions [START_REF] Berney | Efficacy of solar disinfection of Escherichia coli, Shigella flexneri, Salmonella Typhimurium and Vibrio cholerae[END_REF]Boyle et al. 2008;[START_REF] Dejung | Effect of solar water disinfection (SODIS) on model microorganisms under improved and field SODIS conditions[END_REF]Gómez-Couso 2009;Heaselgrave et al. 2006;[START_REF] Joyce | Inactivation of fecal bacteria in drinking water by solar heating[END_REF]Méndez-Hermida 2007;[START_REF] Mcguigan | Solar disinfection of drinking water contained in transparent plastic bottles : characterizing the bacterial inactivation process[END_REF][START_REF] Rijal | Synergistic effect of solar radiation and solar heating to disinfect drinking water sources[END_REF]. It has been shown that a synergistic effect in low-turbidity water is observed when water temperature exceeds 45 o C, at which point the combined inactivation effectiveness is greater than the individual contributions of radiation and heat [START_REF] Mcguigan | Solar disinfection of drinking water contained in transparent plastic bottles : characterizing the bacterial inactivation process[END_REF]. The effectiveness of the SODIS method at decreasing diarrheal incidence has also been investigated in epidemiological intervention studies and has proven to be credible: a decrease in diarrhea incidence by as much as 86% has been observed (Centre for Disease Control 2008; [START_REF] Graf | Health gains from solar water disinfection (SODIS): evaluation of a water quality intervention in Yaoundé, Cameroon[END_REF]Meierhofer 2006;World Health Organization 2002). The method has shown to be particularly effective at reducing diarrhea in children under the age of five (Conroy et al. 1995;1996;[START_REF] Conroy | Solar disinfection of water reduces diarrhoeal disease: an update[END_REF]2001;[START_REF] Graf | Health gains from solar water disinfection (SODIS): evaluation of a water quality intervention in Yaoundé, Cameroon[END_REF]Rai et al. 2010;[START_REF] Rose | Solar disinfection of water for diarrhoeal prevention in southern India[END_REF].

The Effect of Turbidity

The World Health Organization has stated that treating turbid water is "a special concern", as turbidity particles shield the UV radiation that inactivates microbes in the water (World Health Organization 2002), which compromises the effectiveness of the SODIS treatment process. Numerous microbiological studies have revealed that highly turbid waters do not allow for the previously mentioned synergistic effect to occur (Gómez-Couso et al. 2009;Kehoe et al. 2001;McGuigan et al. 2008). Treatment of highly turbid waters is possible, but requires achieving temperatures of at least 55 o C [START_REF] Joyce | Inactivation of fecal bacteria in drinking water by solar heating[END_REF]. At such high temperatures and high turbidity, inactivation occurs by pasteurization; that is, by thermal mechanisms only: McGuigan et al. (2008) showed that in highly turbid water (200 NTU), 99% inactivation of E. coli occurred only 1 cm into the optical path. There is therefore a significant need for a low-cost, practical method for reducing turbidity in source water prior to treatment by solar disinfection, which would allow for faster treatment.

Suspended colloidal particles

Relatively large and dense solid particles have settling velocities high enough such that they will settle in aqueous solution due to gravity. However, colloidal particles remain suspended due to their small size and (generally) electronegative surface charge. One method of inducing the settling of colloidal particles is through the process of coagulation-flocculation, by which colloids are destabilized and aggregated, ultimately resulting in their removal. The use of polyelectrolytes to facilitate coagulationflocculation has been studied and applied extensively, especially in the treatment of suspended particles in industrial water and wastewater treatment processes. Mainly the polyelectrolytes alum and ferric salts are used (Alaerts & Van Haute 1983), due to their high valence charge, which facilitates adsorption onto the colloidal particle [START_REF] Alaerts | Stability of colloid types and optimal dosing in water flocculation[END_REF][START_REF] Juo | Tropical soils : properties and management for sustainable agriculture[END_REF]. The use of coagulation-flocculation in water treatment in developing countries has been tested and proven to be effective; however, the availability of these chemicals and relatively high cost place this treatment method beyond the means of many people (World Health Organization 2002). The use of Moringa Oleifera has shown to be effective at reducing turbidity as well as improving microbial quality in water [START_REF] Nkurunziza | The effect of turbidity levels and Moringa oleifera concentration on the effectiveness of coagulation in water treatment[END_REF][START_REF] Pritchard | Potential of using plant extracts for purification of shallow well water in Malawi[END_REF][START_REF] Ferreira | Coagulant and antibacterial activities of the water-soluble seed lectin from Moringa oleifera[END_REF]); however, it is not available in all regions of concern and the process requires extraction of the lectin from the seed.

Sodium content

For acclimatized adults, the physiological need for sodium is 184-230 mg/day [START_REF] Dahl | Salt and hypertension[END_REF], attainable by consuming about 460-575 mg/day of NaCl. However, average daily sodium intake values vary across countries, age, and gender [START_REF] Elliot | Sodium Intakes Around the World -Background document prepared for the Forum[END_REF]. Tolerable limits and reference values vary similarly. For the purpose of this study, the tolerable upper limit of daily salt intake for North Americans of 5800 mg, corresponding to approximately 2400 mg of sodium (Food and Nutrition Board, 2004), was used as a maximum allowable limit for a user's intake of sodium due to water treated with NaCl. Based on data from North American men and women, it is recommended that the average healthy adult male consumes 3.7 L/day of water from all sources (food and drinking water), and women should consume on average 2.7 L/day (Food and Nutrition Board 2004). This implies that for a SODIS user consuming the North American average of 3.7 and 2.7 L/day of water treated with the proposed NaCl method, the sodium content must not exceed 650 mg/L for men and 890 mg/L for women, and should be as low as possible so as to allow intake of sodium through food. It should be acknowledged that SODIS users are likely to consume less drinking water and salt than the North American reference values. The taste threshold for NaCl in water is approximately 640 mg/L [START_REF] Wiesenthal | Characteristics of salt taste and free chlorine or chloramine in drinking water[END_REF]); therefore, concentrations in the supernatant should not exceed this value, which corresponds to approximately 256 mg/L of sodium

Research goals

This bench-top experiment investigates the effectiveness of a readily available electrolyte, sodium chloride (NaCl) in reducing turbidity in waters due to colloidal clay particles. The flocculating behaviour of different types of clay in saline solutions has been documented [START_REF] Akther | Sedimentation characteristics of two commercial bentonites in aqueous suspensions[END_REF][START_REF] Gibbs | Coagulation rates of clay minerals and natural sediments[END_REF][START_REF] Gibbs | Settling velocity, diameter, and density for flocs of illite, kaolinite, and montmorillonite[END_REF][START_REF] Hsi | Flocculation of selected clays by various electrolytes[END_REF][START_REF] Panayiotopoulos | Influence of Electrolyte Concentration, Sodium Adsorption Ratio, and Mechanical Disturbance on Dispersed Clay Particle Size and Critical Flocculation Concentration in Alfisols[END_REF]. Furthermore, there is potential for the well-known flocculating behaviour of clays to apply to complex clay and mud combinations [START_REF] Mietta | Influence of shear rate, organic matter content, pH and salinity on mud flocculation[END_REF]). The effectiveness of NaCl at reducing turbidity due to colloidal clay particles in the context of household water treatment may significantly impact the availability of SODIS as a household water treatment option in developing countries.

Methodology

Preparation of turbid samples

The following types of clays were tested for their flocculating behaviour with NaCl: kaolinite, illite, and sodium bentonite, which naturally occur tropical soils (Gómez-Couso et al., 2009;[START_REF] Juo | Tropical soils : properties and management for sustainable agriculture[END_REF]. The preparation of the turbid samples followed that outlined by Gómez-Couso et al. (2009). Soil was added to 1000 ml of distilled water to obtain turbidity levels of 50, 100, and 200 NTU, covering a wide range of possible field conditions as outlined by [START_REF] Mcguigan | Solar disinfection of drinking water contained in transparent plastic bottles : characterizing the bacterial inactivation process[END_REF].

Concentrations of NaCl

Five different concentrations of NaCl were tested originally in order to find the range in which the optimal concentration exists. These concentrations were 0.001 M, 0.005 M, 0.01 M, 0.05 M, and 0.1 M, corresponding to 0.0584 g, 0.2922 g, 0.5844 g, 2.922 g, and 5.844 g of NaCl per liter, respectively. Once the minimum concentration that produced a supernatant of <30 NTU was found, the range in which the optimal concentration lies was narrowed to between 0.5844 g and 2.922 g. Further testing was then conducted to determine the optimal amount of NaCl using concentrations of 0.013 M, 0.017 M, 0.021 M, 0.026 M, 0.030 M, and 0.034 M, corresponding to 0.75 g, 1.00 g, 1.25 g, 1.50 g, 1.75 g, and 2.00 g of NaCl per liter of water.

Coagulation-flocculation with NaCl

Standard jar test experiments were conducted to determine the flocculating behaviour of NaCl with each type of clay, as outlined in the ASTM Standard Practice for Coagulation-Flocculation Jar Test of Water (D2305-08). Temperature was held constant at 21 ± 0.5 o C. Samples were flash-mixed for a period of 1 minute at 130 rpm and then underwent slow-mix at 15 rpm for a period of 20 minutes. Samples were then allowed to settle for 60 minutes, and qualitative and quantitative observations were recorded at 15-minute increments. Turbidity was measured with a portable Orbeco turbidimeter and is expressed in NTU, following the procedure outlined in the ASTM Standard Test Method for Determination of Turbidity Above 1 Turbidity Unit (D7315-07a). pH was monitored with a Fisher Accumet 1003N portable pH meter.

Quantity of sodium ions present in supernatant

25 ml of supernatant was collected at a depth of 60 mm and then heated to 90 o C for 300 minutes with 2 ml of 1.0 M HNO 3 to ensure any solids were completely dissolved in the solution. Quantitative inductively coupled plasma by optical emission spectroscopy (ICP-OES) analysis of the sodium ions present in the supernatant was then performed with a Varian Vista AX CCD Simultaneous ICP-AES.

The entire procedure was repeated for a second suite of trials.

Results

Changes in turbidity

NaCl in pure solutions of bentonite was found to be very effective and demonstrated as high as 98% removal efficiency as can be seen in Figure 1. For solutions of kaolinite and illite, NaCl was effective at reducing turbidity to below the 30 NTU SODIS threshold only when the initial turbidity was 50 NTU, corresponding to a maximum removal efficiency of 50%. All data points shown are the average of three measurements with the turbidimeter, corresponding to a maximum error of 5.5%.

Figure 1 illustrates the settling kinetics of pure bentonite suspensions for: a) 50 NTU, b) 100 NTU, and c) 200 NTU. The eye-guide horizontal line at 30 NTU is the SODIS limit and the concentrations of salt that exceed the allowable limit are marked with an asterisk.

Changes in pH

For varying initial turbidity levels, initial pH ranged from 6.3 to 8.1 for bentonite solutions, 5.1 to 5.8 for illite solutions, and 5.2 to 5.8 for kaolinite solutions, reflecting the natural alkalinity and acidity of these types of clays. Overall it was found that pH varied at most by 0.4 over the course of settling, decreasing slightly for solutions of bentonite and increasing slightly for solutions of kaolinite and illite.

Sodium concentration in supernatant

Figure 2 illustrates the concentration of sodium remaining in the supernatant of suspensions that settled below the SODIS threshold of 30 NTU in 60 minutes. As shown in Figure 2, ideal results tend toward the lower left-hand quadrant. The solid horizontal line denotes the maximum health limit based on an intake of 2400 mg of sodium per day.

Discussion

Effectiveness of NaCl at reducing turbidity

The results show that NaCl can be used to effectively reduce turbidity in water containing colloidal particles of high-activity clays such as sodium bentonite. This is because when NaCl is added to a suspension of sodium bentonite particles, the accumulation of sodium ions decreases the thickness of the electric double layer and reduces the hydration of the clay particles, causing flocculation (Roscoe Moss Company 1990). Kaolinite and illite were not as responsive to the addition of NaCl in the solution due to their relatively low cation exchange capacity (CEC) and mineral structure. Turbid source water containing these types of colloidal particles is likely not suitable for treatment with NaCl.

For pure bentonite with an initial turbidity of 50 NTU, 1250 mg/L of NaCl was required to facilitate settling to below the SODIS threshold. However, only 1000 mg/L of NaCl was required for suspensions with an initial turbidity of 100 and 200 NTU. Furthermore, greater percent reductions in turbidity were observed for samples with a relatively high initial turbidity, consistent with flocculation-coagulation mechanisms and the "jumpstart" effect that has been applied in industrial wastewater treatment, in which bentonite is added to turbid solutions to more efficiently facilitate flocculation [START_REF] Yang | Experimental Study of Wastewater Treatment of Reactive Dye by Phys-Chemistry Method[END_REF]. The results also suggest that water with an initial turbidity greater than 200 NTU may possibly be treated with these concentrations of NaCl with desirable results.

Sodium content

Though a range of NaCl concentrations produced supernatant turbidities below the SODIS threshold of 30 NTU, only those that satisfy health and taste limits may be considered as suitable for subsequent use as drinking water. As shown in Figure 2, a maximum concentration of 1500 mg/L of NaCl could be used without exceeding the allowable limit of 600 mg/L of sodium in the supernatant; therefore, only those solutions in which a maximum of 1500 mg/L of NaCl was added may be considered for drinking water use. While none of the supernatants contained sodium below the taste threshold of 256 mg/L, several fell below the sodium content in Gatorade (~460 mg/L), which suggests that certain solutions may be suitable for drinking water. Even if certain samples of water treated with the current method may not be suitable for drinking purposes, all of them may potentially be used for sanitation and hygiene purposes following SODIS treatment.

Implications of study

The results of the current study show that NaCl may be an effective means of reducing turbidity in water caused by naturally occurring high-activity colloidal clay particles. The results also suggest that NaCl, in combination with high-activity clay, may be used to treat turbid water according to the jumpstart effect utilized in industrial water treatment. Both implications may appreciably broaden the scope of people with access to SODIS as a household water treatment.

Future studies

It is recommended that the flocculating behaviour of NaCl with suspensions of calcium bentonite and magnesium bentonite be explored. Following these bench tests, field studies should be conducted in areas dominated by high-activity clays to determine if the results of bench tests are reproducible at the field scale and in relatively uncontrolled conditions. Studies should be conducted to explore the use of bentonite additives in combination with NaCl to produce a small-scale jumpstart effect. Optimization of this technology should be explored by determining the influence of controlled pH on settling. Furthermore, literature shows that bentonite has been used in the removal of contaminants in Sudan [START_REF] Madsen | Low technology water purification by bentonite clay flocculation as performed in Sudanese villages: bacteriological examinations[END_REF]. Thus future work is needed to investigate the effectiveness of bentonite and NaCl combinations in removing microbiological contaminants. If the current method is deemed suitable for use in the field, a detailed cost analysis and life cycle analysis should be performed for comparison against other treatments. Further work must be done to explore and identify all possible health risks associated with this type of technology if the treated water is to be used for drinking purposes, particularly as they relate to sodium intake in various populations.

Conclusions

With appropriate social programming, SODIS has proven to be effective at reducing diarrheal incidence associated with microbiologically contaminated water in developing communities around the world. However, its synergistic mechanisms are limited to relatively clear water of less than 30 NTU; therefore, a simple and appropriate method of reducing turbidity prior to SODIS treatment may significantly expand the number of users with access to SODIS. This study has shown that NaCl, in combination with highactivity clay particles in solution, may effectively reduce turbidity to levels suitable for SODIS treatment. This may appreciably increase the number of people who can practice SODIS as a means of accessing clean water for sanitation purposes, and with some improvement, for drinking purposes. Future work should address the viability of this technology with different types of bentonite and at the field scale, as well as the effectiveness of bentonite and NaCl combinations at reducing microbiological content in water.

Figure 1 .

 1 Figure 1. Settling kinetics of 100% bentonite suspensions from an initial turbidity of a) 50 NTU, b) 100 NTU,and c) 200 NTU. The concentrations marked with an asterisk resulted in supernatants with a sodium concentration that exceeds allowable limits.

Figure 2 .

 2 Figure 2. Sodium content remaining in supernatant after 60 minutes of settling with a final turbidity of less than 30 NTU.

To be published: Brittney Dawney and Joshua M. Pearce, "Optimizing the solar water disinfection (SODIS) method by decreasing turbidity with NaCl", Journal of Water, Sanitation and Hygiene for Development 2(2) pp,87-94 (2012). doi: 10.2166/washdev.2012.043


Clément Sieutat

Céline Chevalier

Alexandre Danescu

Grenet Geneviève

Philippe Regreny

P Viktorovich

Xavier Letartre

Jean-Louis L Leclercq
email: jean-louis.leclercq@ec-lyon.fr

G Grenet

P Viktorovitch

3D optical micro-resonators by curving nanostructures using intrinsic stress

Keywords: 3D Photonic crystal, optical microcavity, microresonator, nanophotonics

come

INTRODUCTION

Today, materials exhibiting designed multidimensional architectures have extraordinary potential for emerging optical applications due to their ability to interact with light in ways that cannot be achieved using simple, non structured materials. Harnessing of light has always been central in the field of nanophotonics. This is usually referred to as photon confinement, whose general definition could be the control of photons within the tiniest possible space during the longest possible time. Fundamentally, the introduction of microstructure with characteristic dimensions similar to the wavelength of light can dramatically modulate light-matter interactions. Increasing dimensionality to two and three dimensions provides opportunities for far more exotic optical properties including 3D photonic bandgaps, metamaterials, optical cloaking, highly efficient solar cells, and unique sensors. 3D photonic crystals (3D PC ) have attracted great interest because they likely provide a means of molding light at the level of physical limits. [START_REF] John | Strong localization of photons in certain disordered dielectric superlattices[END_REF] Only three dimensional photonic crystal can possess a complete photonic band gap, which potentially confines light in a small space due to omnidirectional inhibition of light propagation. The general approach to achieve strong confinement of photons consists in high index contrast structuring of space at the wavelength scale, which is in the submicrometer range for the optical domain. Proposed applications for photonic bandgap materials are quite diverse, and include lossless mirrors, the enhancement or inhibition of emission from embedded emitters, 2 zero-threshold lasers, [START_REF] Yablonovitch | Inhibited spontaneous emission in solid-state physics and electronics[END_REF] low-loss 3D micrometer-scale optical waveguides, 4 optical circuitry, enhancement of optical absorption processes in solar cells, and sensors. [START_REF] Inoue | Photonic crystals: physics, fabrication, and applications[END_REF] Today, design and fabrication of multidimensional architectures for functional optical devices are of great interest, especially for bio and health applications (such as sensing, fluorescence imaging) where people are trying to strengthen the interactions with biological molecules or nanoparticles. For that, one needs to develop new strategies to confine light in air or, more generally, in low index materials like liquids or gas.

Fabrication technology of three-dimensional complete photonic bandgap materials in the optical domain is extremely complex. Two-dimensional photonic crystals (2D PC) are far more accessible than 3D PC, since they may be fabricated using planar technological schemes that are familiar to the world of integrated optics and microelectronics. Fabrication of three dimensional structures is then a significant challenge to be addressed. V.Y. Prinz et al. have first demonstrated such capabilities by fabricating nanotubes, nanowires and nanocoils using the strain relaxation of semiconductor layers. [START_REF] Prinz | Free-standing and overgrown InGaAs/GaAs nanotubes, nanohelices and their arrays[END_REF] It was then considered as an emerging technology with a broad spectrum of possible applications. [START_REF] Li | Strain induced semiconductor nanotubes: from formation process to device applications[END_REF] This technological approach combined with our 2.5D nanophotonics concept 8 yield us to design and create original 3 dimensional Micro-Nano-Photonics devices ('Optical Origami'). It is mainly a question of exploring and of combining new scientific and technological concepts founded on engineering of mechanical constraints to generate objects of various forms at the wavelength scale and to achieve a real 3D control of the light. In that purpose we have recently proposed a new concept of trapping photons in real 3D optical microresonators that can be assimilated to 'photon cages'. [START_REF] Sieutat | 3d harnessing of light with photon cage[END_REF] The paper is organized as follows: the second section presents the basic principles and simulations associated to an "ideal" spherical object. The third section discusses about the basic mechanical ingredients needed for curvature and thickness control during fabrication, and presents numerical simulation of the folding problem for a "generic spiral object". In the fourth section we present the technological issues involved in the fabrication of three-dimensional objects and the design problem.

PHOTON CAGE PRINCIPLES

Novel class of highly efficient optical microcavities based on the 2.5D photonic crystals concept have been developed in our group. These are provided using ultra-thin and highly-efficient photonic crystal slab mirrors instead of conventional DBRs. A quasi-3D harnessing of the light at the wavelength scale are then obtained via the controllable interplay occurring between waveguided confined photons within the PC slabs and radiated photons propagating through the planar multilayer structure, at a far lower technological cost than pure 3D PC. 10 3D microcavities presenting closed geometries can be generated deviating from these ultimate photonic crystal mirrors-based vertical Fabry-Perot microcavities. These 'photon cages' can be seen as 'physical' deformation of the geometry of the vertical microcavity as shown schematically in Figure 1. By generating these micro-objects with various closed geometries (spires, tubes, rolls) at wavelength scales combined with dedicated optical modes engineering may yield to a tight spatial and spectral control of photons in the low index part (air region). Since these objects are mainly composed by air, their ability to sense or trap nanoparticles which can interfere with the cage resonant modes are drastically enhanced. In this article we focus on a specific 3D photonic structures which is a spherical cavity obtained by the relaxation of patterns formed in pre-stressed multi-layer structures (Figure 2).

Simulating the electromagnetic properties of the 3D microstructure

The electromagnetic properties of the three-dimensional photon cage were obtained using numerical simulation software developed at the Institut des Nanotechnologies de Lyon (Tessa). The software performs 3D FDTD simulations from an input file containing a discrete description of the refractive index. In order to build such a file, the coordinates of enough points on the 3D curve should be gathered, i.e., the sampling distance should be shorter than the space mesh. The parametric equation of the photon cage is given in (1), where R is the radius and N the number of turns in one half of a sphere (-

2N π ≤ θ ≤ 2N π) X(θ) = R sin( π 2 - θ 4N ) cos(θ), Y (θ) = R sin( π 2 - θ 4N ) sin(θ), Z(θ) = R cos( π 2 - θ 4N ) (1)
The curve itself is not sufficient to describe the photon cage and forms only the core of the structure. Depth and thickness around the curve must be added in such a way that they follow the progressive slope of the III-V SC material "ribbon" on each point of the curve. The orientation of the local Frenet-Serret frame can be obtained using the normal and binormal vectors (Figure 3). Let us consider a rectangle having the same dimensions as the section of this "ribbon". In order to obtain the 3D microstructure it can be centered on the curve and oriented using these vectors. With a sufficiently small step along the arc-length, the spherical photon cage representation can be realized (Figure 3). In addition this approach can be applied to build many other 3D microstructures starting from their parametric curve. In particular helical structures have been successfully designed using this method. An educated guess of the dimensions of the microstructure have been derived from a previously designed high reflectivity broadband 1D PhC mirror similar to Figure 1. [START_REF] Boutami | Ultimate vertical Fabry-Perot cavity based on single-layer photonic crystal mirrors[END_REF] The thickness (along the binormal vector) is 0.40µm and the period along a longitudinal axis is 1.1µm, leading to an approximate filling factor in material of 0.36. Finally the depth (along the normal vector) is 0.25µm and the sphere radius is 2.8µm. The electromagnetic properties of the spherical photon cage have been then determined by 3D FDTD simulations. A spatial step of 40nm was chosen. The source consists in a dipole vibrating in the center of the cage. The value of the electromagnetic field is recorded on an off-center point after extinction of the source. A resonant mode is observed at 1.49µm with a quality factor of Q = 280. It is worthwhile to notice the high field concentration reached at the center of the cage (Figure 4), although the cavity is composed mainly of air. Further tunings of the dimensions are expected to give modes with higher Q-factor. In order to fabricate such structures we will use the relaxation of patterns formed in pre-stressed multi-layer semiconducting material. Then mechanical simulations are needed to design the flat shape that will give the final three-dimensional object (Figure 2) through the stress relaxation process.

CURVATURE CONTROL AND DESIGN OF THREE-DIMENSIONAL OBJECTS

This section presents the details of the mechanical side of the problem intended to : (i) discuss the dependence of a stress-free bilayer and delineate the compositions, thicknesses and misfit restricted by some technological constraints and (ii) the design problem relating the design of a two-dimensional mask to the shape of a stress-free three dimensional object.

Curvature of the (A, h A )/(B, h B ) stress-free bilayer

We consider an elastic layer A (thickness h A ) grown on an elastic layer B (thickness h B ). Let m = aB -aA aA be the in-plane misfit between the A-layer and the B-layer and C A and C B denote the Hooke tensors of the layers. With respect to the stress-free reference configuration of the B layer, the reduced constitutive law (Hooke law under plane stress assumptions) for the two materials are

• For the layer A : σ = C A [ε + m] where m = mI 2×2 . • For the layer B : σ = C B [ε]
As usual in classical plate theory the strain of the bilayer can be written as the sum between two terms:

ε = ε 0 + zκ (2)
where ε 0 and κ represent respectively the in-plane strain and curvature of the bilayer. In (2) the vertical coordinate z is measured from the middle plan of the bilayer. The etching process renders the bilayer stress-free and thus induces both an in-plane strain and a curvature and the values of these can be obtained by imposing that the generalized efforts vanish. We obtain the system of equations

( A B B t D ) ( ε 0 κ ) = ( N 0 M 0 ) (3)
where

A = h A C A + h B C B , B = 1 2 h A h B (C A -C B ), D = 1 12 [ h A (3h 2 B + h 2 A )C A + h B (3h 2 A + h 2 B )C B ] (4)
and

N 0 = h A C A [m], M 0 = 1 12 h A h B C A [m]. (5)

Solution in the general case with cubic symmetry

If both materials A and B have cubic symmetry it follows that ε 0 12 = κ 0 12 = 0. Also from symmetry considerations we obtain ε 0 11 = ε 0 22 and we denote their common value by ε 0 . A similar result holds for the curvature where κ 11 = κ 22 so that we use κ for their common value. If we denote the plan modulus

Y A,B = C A,B 11 +C A,B 12 = E A,B 1-ν A,B
the system (3) reduces to the two equations for ε 0 and κ in the form

{ (h A Y A + h B Y B )ε 0 + 1 2 h A h B (Y A -Y B )κ = -mh A Y A 1 2 h A h B (Y A -Y B )ε 0 + 1 12 [h B (3h 2 A + h 2 B )Y B + h A (3h 2 B + h 2 A )Y A ]κ = -1 2 h A h B Y A m. ( 6
)
In the following it is convenient to introduce the contrast C = Y A /Y B and the thickness ratio ξ = h A /h B . The system (6) becomes

{ (1 + ξC)ε 0 + 1 2 (1 -C)κ = -m (1 -C)ε 0 + 1 6 [(3ξ + 1 ξ )C + 3 + ξ 2 ]κ = -m. ( 7
)
where κ denotes h B κ. Finally, the curvature of the bilayer is given by

κ = -× Cξ(1 + ξ) ξ 3 + C 2 ξ(3ξ 2 -2) + C(1 + 6ξ + 6ξ 2 + ξ 4 ) 6m h B ( 8
)
which leads to κ = -6m h B ξ 1+ξ 3 in the case when C ≃ 1. It is interesting to notice that the maximum curvature at given misfit is obtained for ξ = 1/2, i.e. when the thickness of the A layer is half of the thickness of the B layer. Back to the general case, if f (C, ξ) denotes the second numerical factor in the right-hand side of (8) at fixed contrast, one can compute the optimal thickness ratio in order to obtain a prescribed curvature. The general behavior of the numerical factor f (C, ξ) is provided in Figure 5.

For example and considering the experimental control during epitaxial growth in the InP/InGaAs material system, it is possible to grow a 25nm thickness Ga 0.15 In 0.85 P layer (the A layer) at 1% tensile strain on top of a 50nm thickness InAs 0.35 P 0.65 layer (the B layer) at 1% compressive strain -with respect to InP lattice parameter. The previous results predict that the macroscopic curvature radius of the stress-free 75 nm bilayer structure GaInP/InAsP will be ≃ 2.7µm.

We conclude this section with the following general remark: as shown by relation ( 8) κ ≃ 1/ρ ≃ 8m 9hB but in practical situations the thicknesses of layers A and B are limited by MBE technology. Increase of m is possible by changing the composition of the two layers but this in turn may decrease the critical thickness of 2d (planar) growth and raise the problem concerning the mechanical resistance of the bilayer after etching.

The design problem

As shown in the previous section, after etching, a free-stress bilayer material (obtained by the successive deposition of two materials with cubic symmetry and controlled thicknesses) will bend and the bending curvature tensor has the general expression κ = κI where κ is given by (8). For completeness, we recall here that the curvature tensor used in the theory of linear elastic plates involves only the lower-order terms of the (geometrically exact) curvature tensor, i.e. κ ≃ -

( ∂ 2 w ∂x 2 1 ∂ 2 w ∂x1∂x2 ∂ 2 w ∂x1∂x2 ∂ 2 w ∂x 2 2 ) . ( 9
C = E A E B 1-ν B
1-ν A (the contrast) ξ = hA/hB (the thickness ratio) Figure 5. Values of the numerical factor f (C, ξ) in ( 8). The continuous line give the thickness ratio (on the vertical axis) as a function of the contrast (horizontal axis) that provides the maximum curvature of the bilayer. As shown, the ratio thickness ξ that leads to maximum curvature take values in the interval (0.4, 0.6) for various values of the contrast C. It is well-known that at this level of approximation the theory of linear elastic plates gives accurate results but it is unable to predict large deformations (as for example the folding of a long sheet) induced by finite displacements including rotations. To overcome this drawback we interpret the (experimentally confirmed) computed value of the curvature tensor in terms of exact geometric curvature * and address here the general design problem relating the form of a planar mask design and the shape of the three-dimensional object obtained after etching through the stress-relaxation process. For feasibility reasons we shall focus first on the folding problem of a given design mask. Then we shall address the unfolding problem, i.e., we look for a planar mask design which after folding will recover a fixed given three-dimensional shape.

The Figure 6 presents 4 successive frames induced by stress-relaxation of a spiral mask on a generic bilayer material. For simplicity the color on the graph represents the elevation of respective point with respect to the horizontal plane where the mask is designed. The perspective in different pictures are different to offer the best view for the three-dimensional object.

The Unfolding Problem The method used for the modeling of the folding problem allows to solve also the unfolding problem. Figure 7 presents 4 frames and the final mask design which after etching will create a spiral three-dimensional frame-wire on a sphere which is the basic object we look for. The numerical results are then implemented through an intermediate algorithm into the mask technology tool. We notice that the size of the final two-dimensional domain is much larger that the initial size of the three dimensional object as indicated by the axes grid (same perspective for all frames). * The details of the adjacent theory, computational method and associated results will be presented elsewhere.

PHOTON CAGE FABRICATION

Fabrication of 3D closed microstructures consists in exploiting the process of elastic relaxation of pattern formed in pre-stressed multi-layer structures. The final shape of these objects are predetermined by the distribution of the deformations in the various semiconductor layers, imposed during their epitaxial growth, before their freestanding from the substrate by selective micromachining. The principal factor of control of the final shape of the objects is the gradient of deformation as explained in the previous section. Of course, the final shape of the 3D structures not only depends on strain gradient, but also on the micromachining parameters (crystallographic directions and etching kinetics).

Method for fabrication of free-standing 3D microstructures from strained InP/InGaAs heterostructure was developed. The epitaxial structure consists of a 25nm thick In(Ga)P -1% tensile -onto 50nm thick In(As)P -1% compressive -strained bilayer on top of a 500nm thick InGaAs lattice matched sacrificial layer grown on (100) InP substrate.

The microspiral formation was done by postgrowth e-beam lithography, vertical plasma transfer through the all InP/InGaAs heterostructure and selective chemical underetching using FeCl 3 for the InGaAs sacrificial layer. The mask pattern used for lithographic patterning contains 2 symmetric spirals tied together by a common central anchorage with diameters varying from 5 to 20µm (see Figure 8 (left side)). The fabrication of the 3D closed microstructure based on the self-rolling up of the 2 spirals was carried out using the following steps: ebeam lithographic patterning on negative resist, CH 4 /H 2 plasma etching to transfer the pattern to the epitaxial structure down to the sacrificial InGaAs. Then a timed control etch using HF : H 2 O : H 2 O 2 was used to laterally remove InGaAs and release the InP-bilayer from the substrate for rolling. A final CO 2 supercritical drying step was applied. Scanning electron microscopy (SEM) imaging was used to examine the topography and dimensions of the formed 3D microstructures (Fig. 8).

PERSPECTIVE AND CONCLUSIONS

A spherical microcavity is demonstrated exhibiting a high confinement of light in its embedded air region. Additional electromagnetic simulations will be done to improve the 3D microresonator properties, especially in terms of modal volume and Q-factor. We demonstrate controlled fabrication of spherical 3D microstructures in order to validate the design principles based on progressive relaxation of the elastic energy accounting for out-of-plane relaxation. We use the pre-stressed InGaP/InAsP bilayer films as a model system, which are grown with good accuracy by molecular beam epitaxy. Experimental works are now under progress considering the unfolding problem, allowing the fabrication of a real spherical microcavity with constant filling factor. We believe that the micro-nanomechanical architecture of strained bilayer thin films can be now considered as very versatile and powerful for fabrication of various original 3D microstructures.

Figure 1 .

 1 Figure 1. Schematic representation of the concept from 2.5D to 3D microcavity. Left: vertical microcavity between 2 photonic crystal slab mirrors. Right: winding of this structure leading to a cylindrical microcavity.

Figure 2 .

 2 Figure 2. A general view of the 3D photonic spherical cavity

Figure 3 .

 3 Figure 3. A Frenet-Serret base is represented of the parametric curve with tangent vector T , normal vector N and binormal vector B (left). 3D view of the spherical photon cage (right).

Figure 4 .

 4 Figure 4. E 2 x field profiles obtained by 3D FDTD on the three main axes: (Y Z) plane (top right), (XZ) plane (bottom left), (XY ) plane (bottom right).

Figure 6 .

 6 Figure 6. Four successive frames obtained by numerical simulation of the stress-relaxation folding problem for a generic spiral mask. The colors (in online version) represent the elevation of different points form the mask plane due to stress-relaxation.

Figure 7 .

 7 Figure 7. Five successive frames obtained by numerical simulation for the unfolding problem of a generic spherical frame.We notice that the size of the final two-dimensional domain is much larger that the initial size of the three dimensional object as indicated by the axes grid (same perspective for all frames).

Figure 8 .

 8 Figure 8. Optical image of the spirals with dimension from 5 to 20µm (upper left part) SEM image of spirals with a diameter of 10µm after development (left). SEM image of the formed 3D spiral with diameter of 5µm (right).

Acknowledgement

Authors are gratefully acknowledging technological staffs from Nanolyon platform. Region Rhne-Alpes is also acknowledged for its financial support through the PhD grant of C. Sieutat.


Anna Joukovskaïa-Lecerf

On the Approaches to the Study of the Russian 18th-century ‗Bureaucratic Apparatus'

In the last ten years, the revival of interest in the study of the Russian Ancien Régime government has resulted in the publication of several important works based on thorough archival research. 1 It seems, nevertheless, that this new and sometimes strikingly original empirical evidence has not yet profoundly influenced the standard historiography. Thus, in a recent collective study on processes of modernization in Muscovy, renowned historians reproduce the habitual scheme, drawing a more or less clear evolutional line that starts from a medieval administration, continues trough a 'patrimonial bureaucracy' of an early modern Western European type, and finally arrives at a bureaucracy approaching, or at least aspiring to ideal Weberian criteria.

1

Peter Brown concludes his synthesis on the 17th-century Muscovite ‗bureaucratic administration' by writing that ‗Russia's bureaucratic processes, expectations, and conduct were [...] a ubiquitous cultural phenomenon, much like computerization in late twentieth-century life. [...] Almost no one had any choice but to conform to bureaucracy's rhythm, be that person a serf, Duma member, or tsar'. 2 Likewise, Richard Hellie states that ‗what was solely a palace administration in 1450 evolved to a differentiated system based on -proto-Weberian‖ functional chancelleries a century or so later', and that the Muscovite chancelleries of the 17th century were staffed by ‗a professional bureaucracy which did not depend on personal relations.' 3 In the present historiographical context, such simplistic commonplaces no longer seem so obvious. This short article deals with just one particular problem, namely the nature, the place, and the role of the aforementioned ‗personal relations' within the ‗professionalized' administrative system of 18th-century Russia.

As is well known, one of the striking features of 18 th -century Russia, in comparison with the preceding period, is that, with the beginning of the reign of Peter I, the Russian monarchy stopped pretending to be a conservative guardian of 2 Peter Brown, ‗Bureaucratic Administration in Seventeenth-century Russia', in Jarmo Kotilaine and Marshall Poe (eds.), Modernizing Muscovy: Reform and Social Change in Seventeenth-century Russia, London and New York, 2004 (hereafter Modernizing Muscovy), pp. 57-78 (p. 78).

3 Richard Hellie, ‗The Expanding Role of the State in Russia ', in Modernizing Muscovy, pp. 29-55 (p. 30). Similar views are expressed by B. N. Mironov, Sotsial'naia istoriia Rossii, St Petersburg, 2 vols, 1999, 2, pp. 162-75. traditions, explicitly presenting itself as an active agent of social change. And though the 18th-century successors of Peter I on the throne were relatively moderate in experimenting with reforms, the abstract notion of change maintained its new and positive meaning of salutary renovation, rather than the ancient and negative one of degeneration and impending doomsday.

With Peter I, legislation came to be considered an important medium of change.

In contrast to the preceding centuries, his lawgiving was interventionist rather than arbitrating and aspired to shape society almost as much as it simply conveyed orders to its members. A domain where Peter I's normative activity attained an utmost intensity and a high degree of abstraction was the internal functioning of the administration. Up to the victory of Poltava in 1709, this sphere was almost without general written norms, apart from several articles of the Law Code of 1649. The government body regulated itself by tradition-rooted practical experience and the common sense of the decision-makers and performing agents. Inspired by contemporary Swedish legislation, Peter I, who disliked native customs and distrusted native common sense, tried to replace both by an ample and systematic corpus of written regulations, statutes and instructions regarding governmental and judicial procedures, and the duties of office. In a solemn public speech in 1719, on an occasion of promulgating these institutions, Peter I proudly compared himself to Noah, destroying the old and vicious world and bringing forth a new and better one. 4 The dominant 20th-century historical interpretation has presented Peter I's institutional reforms as one of the most important vehicles of modernization during the life of at least two generations that followed his reign. Now, however, this historiographical trend seems distinctly outdated, and historians tend to agree with Peter's sceptisism about the effective power of regulations to shape society and even government, for it did not escape the tsar that his servitors, in his own words, managed ‗to play cards' with the laws he wrote for them. 5 Today, Peter I's prescriptive instruments might be more usefully analysed in terms of cultural monuments.

One of the most important and still almost neglected aspects of this problem is the nature of the hierarchical work relationship among the personnel of Peter's administrative bureaus. I use this expression to denote a complex relational phenomenon that can be observed taking place between the members of a given governmental agency considered as a collective action. On the one hand, its members are bound by functional links, the existence and nature of which are more or less independent of individual wills, being defined by the practical tasks the agents have to perform, such as collecting taxes or recruiting soldiers. The horizontal division of duties among the servitors and the vertical relation of command and obedience between superiors and subordinates constitute the functional body of the work relationship. On the other hand, cooperation between men presupposes a certain degree of personal relations that depend upon multiple general and individual factors, 5 Ukase of 17 April 1722, Zakonodatel'nye akty Petra I, ed. N. A. Voskresenskii, Moscow and Leningrad, 1945, No 132, p. 107. such as social origin and economic position, age, competence, cultural background, temperament, and charisma, as well as habits, customs, working conditions, among others. Personal relations are integral to the work relationship and cannot be separated from the functional links other than in theory, though it does not mean that the historical agents did not distinguish between the two. The nature of both relational components and, more importantly, the mode of their coexistence within a work relationship are subject to variations in time and space, but in some instances they are stable enough to create patterns discernible not only from a long temporal or cultural distance, but also on a contemporary and local scale.

Considering the history of government from the angle of work relationships has the advantage of revealing its dynamic nature. From a strictly methodological point of view, it resolves the current separation between the study of government agencies and the prosopographical study of personnel and so forth. This globalising effect, as it were, is particularly valuable in the case of Russian history of the 18th century. Here, government agencies on one hand and the so-called bureaucracy on the other, have been reified to a particularly exaggerated degree. In a symptomatic manner, historians usually refer to the realities they study as a government apparatus, bureaucratic machine or administrative mechanism. Such metaphors successfully obscure the fluid, negotiable nature of work relations, that were characteristic of the early modern and 18th-century Russian government.

While the relational perspective I am advocating has never been systematically applied in standard studies of Russian administration, 6 it has naturally been employed by those interested in the phenomena of personal loyalty and patron-client relations, but without paying any special attention to government personnel. 7 It might be due to this indiscriminate approach that the results in this sphere do not seem entirely convincing. Thus, it has been stated that up to a certain stage of historical development, patron-client relations played a positive role in government, because they enabled the transmission and fulfillment of orders through informal power chains where institutions were lacking or insufficient. But the emergence of the Modern State, supported by a functional bureaucracy supposedly brought about by Peter's reforms, would have promoted a formal and impersonal kind of vertical relationship, while the patron-client relations would have become a serious drawback for the efficiency of the administrative system, and thenceforth a synonym for corruption. Besides, those 18th-century officials who were part of an Enlightenment- Letter-writer', in Frederic Jaher (ed.), The Rich, the Well-born, and the Powerful: Studies of Elites and Upper Classes in History, Urbana, Chicago, and London, 1973, pp. 154-78, and ‗Character and Style of Patron-client Relations in Russia', in Antoni Mączak (ed.), Klientelsysteme im Europa der Frühen Neuzeit, München, 1988, pp. 211-31; E.N. Marasinova, Psihologiia elity rossiiskogo dvorianstva poslednei treti XVIII veka (po materialam perepiski), Moscow, 1999, pp. 99-117. influenced educated elite would have come to associate patron-client relations with abasement of an individual's honour. As it is easy to notice, this interpretation is based on an implicit equation between the personal ingredient of the work relationship and patron-client relations. The object of the pages that follow is to show what exactly seems incorrect in the analysis of the hierarchical work relationship within the context of patron-client studies, and to present research approaches that it seems necessary to develop.

As I have already underlined, historians who have tackled the problem of patronage and clientelism in the 18th-century Russia have implicitly admitted an a priori equation between the personal ingredient of the hierarchical work relationship and the patron-client link. This attitude is explained by the fact that, speaking in abstract terms, the personal ingredient of the hierarchical work relationship corresponds with a theoretical definition of the patron-client link used by most historians: a ‗dyadic, personal, vertical, unequal, reciprocal, exchange relationship.' 8 But we should consider that while the hierarchical work relations were, in fact, profoundly personal, they were not automatically perceived as patron-client ones by the actors, nor judged as such by contemporary observers. This can easily be seen as well in the 17th as in the 18th century. Let us take a look at the pre-reform Muscovite offices and their provincial town branches (prikazy and prikaznye izby). The superiors normally possessed an almost complete discretion 8 Sharon Kettering, Patrons, Brokers, and Clients in Seventeenth-Century France, New York and Oxford, 1986, p. 20. with regard to their subordinates, though the latter were not confused with personal servants. A superior recruited servitors, decided all questions concerning their career and remuneration, served as a unique intermediary between them and the tsar, judged the personnel for civil and criminal offences, ordered and surveyed the execution of punishment, and so on. On the other hand, the superior was dependent upon his subordinates' services, and his discretionary powers had to be used not so much as a tool of compulsion, but also as a resource for negotiation. In this system, the execution of tasks related to the tsar's service and not lucrative in themselves were not otherwise obtained from the subordinates in exchange for some gain, privilege or advantage for them. To be sure, negotiation took the form of reverential supplication and free gift, but the servile language of the subordinates did not annul the bargaining character of their procedure, as might be seen from cases when subordinates disobeyed the superior who would not or could not follow the exchange logic.

We have very limited evidence of the superiors hiring, or at least occasionally gratifying, personnel at their own expense. Normally, they obtained what might be called exchange capital from the tsar. Thus, a superior who needed the cooperation of his subordinates was bound to extend his protection over them. If we analyse his behaviour in terms of the patron-client paradigm, he appears to have been acting as a broker, a form of patron distributing his own patron's resources. But from the historical actors' point of view, to be identified as patron and client, two individuals had to present symptoms of particular proximity. The customary and standardized personality integral to the work relationship was not individualized enough to be perceived in this light. 9

Peter I expressed a most intense aversion toward the discretionary powers of his senior servitors, whom he publicly characterised as ‗those judges who act as they choose.' 10 His institutional reforms were intended primarily to change this basic feature of Russian government. As is well known, the most drastic changes concerned the central administration. The principal prikazy were dismantled and replaced by ‗colleges' directed by a president with a board of counsellors. Peter stripped the central agencies of their independent sources of income, centralising his finances in a single treasury. He introduced detailed college budgets and salary charts for the whole staff, and gave the entire power over the budgets, the charts and, of course, promotions, to a single institution, the Senate, under his direct control. He also organized independent courts of justice, and tried to transfer the college personnel under their jurisdiction.

It seems clear that such measures could have changed the overall protection mode based on personalized exchange of services described in the previous paragraph. But the old Muscovite practices largely survived the whirlwind of these reforms. If we take a closer look at the colleges, we can see that they functioned not only in much the same way, but that some of the old customs finally received a formal confirmation in the new Petrine legislation. 11 This outcome of the reform was 9 Anna Zhukovskaia, ‗Ot porucheniia k uchrezhdeniiu: A.A. Kurbatov i -krepostnoe delo‖ pri Petre I', Ocherki feodal'noi Rossii, 13, St-Petersburg, 2009 (in print).

10 Ukase of 19 December 1718 (Zakonodatel'nye akty Petra I, No 381, p. 378).

11 Anna Joukovskaïa-Lecerf, ‗Hiérarchie et patronage: Les relations de travail dans not solely an effect of inertia retained in new agencies still heavily staffed with the former personnel. It was the result of active opposition on the part of the college superiors. These men were persuaded that their power to command obedience was dependent upon the maintenance of the personalised protection-counter-services relationship with the subordinates. The most articulate opponent of reform, Andrei Osterman, a university-trained German who became vice-chancellor after progressing step by step through the Russian Foreign Service, bluntly declared that no college president would be capable of commanding the personnel if he were deprived of complete control over remuneration funds and promotions.

In a nutshell, the so-called fledgelings of Peter I's nest seem to have believed that the colleges were able to fulfill their manifest function of administrating the country just as long as their presidents continued to act as coordinators of the college's latent function of extending protection to the personnel.12 This mode of operation persisted during the whole of the 18th century, and probably well into the 19th. A Petrine college president behaved like a servant of the monarch charged with a certain task and used material, symbolic and other power resources afforded to him by the Crown to force the necessary individuals to fulfil this task. He was very far from the type of a state official entrusted with the direction of a public service.

The college of Foreign Affairs under the direction of Osterman and his l'administration russe au XVIIIe siècle', Cahiers du Monde russe, 47, 2006, 3, pp. 551-80. successors offers a good example of how the overall protection mode and patronclient relations coexisted in a single frame of the hierarchical work relationship.

Contrary to all Petrine regulations, this college had two communicating but distinctive executive levels: an official department, and a (usually) smaller office of the minister, the existence of which was never institutionally recognized or made public.

This structure emerged spontaneously. Every successive minister arriving at the head of the college of Foreign Affairs surrounded himself with a relatively restricted circle of servitors picked from among the departmental personnel. The choice men were given more important responsibilities, worked more and were remunerated accordingly on a larger scale than the rest of the servitors. The latter included many aged persons who lived in retirement with the tacit consent of the minister, while the younger ones did some deciphering and translation, but in general were not much occupied. Accordingly, they did not benefit from any special promotions or material advantages, and though some of them had very comfortable careers, their advancement was never rapid or spectacular.

The servitors in the small office were not automatically considered as the minister's clients by their colleagues, or by foreign diplomats. This happened if the minister treated them on more intimate terms, lodging them at his house, inviting them to his table, playing cards with them, introducing them to his friends, as well as giving them tasks that had little to do with their office, such as handling his private correspondence. Catherine II's minister Nikita Panin went as far as to give several subordinates with whom he was on most intimate terms a part of his own land and peasants -a gesture that was judged as a mark of an advanced patron-client relationship.

An interesting document from the archive of the college of Foreign Affairs illustrates the modalities of coexistence between the overall protection mode and the patron-client mode in this government agency. In 1762, Catherine II ordered a general revision of the college budgets by the Senate. The ministers of Foreign Affairs traditionally opposed themselves to any intervention by the government into the financial management of the college, so this time Nikita Panin ignored the order.

But his subordinates (those who did not have the chance to be his clients) used this occasion to draw up a new college budget accompanied by a series of propositions concerning the treatment of the personnel. They asked for pensions after retirement, stipends for educating their sons, preferential recruitment to the college of Foreign Affairs for their sons, pensions for their widows, and so on. There was nothing extraordinary in the list of privileges itself, for, as I have shown, they were customary for government agencies. The radically new and exciting thing about this text is its form, which broke completely with the ancient tradition of supplication. The authors did not ask for individually-accorded privileges, but demanded a right, legally defined and promulgated by the monarch, which would apply to everyone who had attained a certain rank in the college service. They explained it by pointing out that the customary goodwill of the college superiors could no longer guarantee the treatment that the college personnel deserved, they said, by its service to the monarch.

The project of 1764 was provoked by a particular context, when the college of Foreign Affairs found itself in a strained financial situation. A lack of cash lasting for several years resulted in an uncommonly profound distinction between the two categories of the personnel: the real clients of the minister in office, who managed to keep their benefits, and the rank-and-file, whose level of protection decreased and who suddenly felt the instability of their situation. In the following years, the financial difficulties of the college were partly resolved, which explains that the personnel did not try to resume its initiative.

The overall protection mode continued to function at least up to the end of the 18th century, though some ministers started to feel uncomfortable about it. Indeed, with more than 400 salaried servitors, the college represented by far the largest diplomatic service in the world, and three quarters of them were considered superfluous: ‗Si vous saviez le désordre qui règne dans le Département, si vous aviez une idée du tas de misérables et de sujets ineptes qui s'y trouvent, vous seriez comme moi persuadé de la nécessité de les renvoyer et fâché de l'impossibilité de ne pouvoir le faire' [If you knew the disorder which rules in the Deparment, if you had any idea of the piles of miserable individuals and inept subjects who are to be found there, you would be as persuaded as I am of the need to dismiss them and angry at the impossibility of ever being able to do this], wrote the last vice-chancellor of the century. 13 The study of the college of Foreign Affairs does not allow us, of course, to draw 13 Letter from V.P. Kotsubei to A.R. Vorontsov, 1799 (Arkhiv kniazia Vorontsova, 40 vols, Moscow, 1870-1895, 14, p. 105).

general conclusions about the situation throughout government agencies. But, on the other hand, this particular case provides access to the basic conditions capable of provoking, but also of suspending impulses of change in the work relationship.

It explains, why we do not observe any clear-cut tendency towards ‗bureaucratisation' in that period.

The overall protection mode did not decrease linearly, but fluctuated in a subtle way, for it depended heavily on working conditions that changed from time to time and varied among agencies. Patron-client relations did not decrease linearly either. In the college of Foreign Affairs they were much less present in the 1730s than in the 1760s and the 1770s, and in the 1790s, they exploded and became different in nature, for the exchange of services was no more predominantly limited to the functional frame of the college service, but expanded to a larger context of the social life of St Petersburg. It seems, in fact, that the patron-client relations became more robust during the periods when the overall protection mode shrunk. Now let us look at the cultural reasons that are supposed to have acted as a reducing agent on patron-client relationsthe ideals of legality introduced by Peter I, and the notion of individual honour internalized by the educated elite by the middle of the century. First, it is necessary to point out, that the elite in question was still extremely limited in number in the 18th century. Second, if we examine closely these cultural mechanisms, it appears they did not work at all in such a straightforward way.

The clientele of Nikita Panin in the college of Foreign Affairs comprised a famous playwright, Denis Fonvizin, who is considered by literary historians as one of the most virulent critics of favouritism and clientelism in the 18th century. But his whole career was deliberately constructed as a patron-client relationship with his two successive superiors. He left the first feeling indignant about the man's incapacity to appreciate his devotion and engage fully in a patron-client exchange. In a letter to his parents, Fonvizin called this superior a monster (urod). 14 The choice of this somewhat unexpected epithet indicates, in fact, that Fonvizin considered such behaviour generally abnormal. With Panin, who proved a good patron, Fonvizin's attitude came to resemble fidelity. He integrated his patron's political views, even though these were in opposition with the regime, and maintained them after the latter's death, notwithstanding the damage it caused to his career. 15 The case of Fonvizin shows well that the estimation of the patron-client relations by the educated elite was a relative one. It was viewed in a positive or in a negative light depending upon the context. A similar attitude can be observed in the writings of another well-known author, the journalist Nikolai Novikov, whose satire aimed at corruption, not the patron-client relations as such. These relations appeared as a neutral phenomenon, and were praised or condemned contextually, according to whether they served just or unjust ends, or produced good or bad effects. 16 Peter I himself, in one of his fundamental ideologically pointed legal texts, pictured the hierarchical work relationship in the following way: It is not infrequent that a judge, or an officer, finding himself in the claws of a passion, feeling obliged, or searching for a gain, commits an offence. Seeing that, his subordinates get out of order, for they are no longer afraid of their superior's wrath, because a partial superior cannot punish his subordinates.

Whenever he starts scolding a delinquent, the latter defends himself unashamedly with false arguments, warning the superior with a glance, or a whisper in his ear, or letting him know through a friend, that if the superior were not indulgent, he would denounce him. And the officer, similar to a slave, must keep silence, tolerate and cover up. What will be the outcome of all this? Nothing but vile living in the subordinates, general fearlessness, a bitterer disaster for the people, and God's anger. And thereof might follow a calamity and a final downfall of the realm. 17

In this citation, one of the possible reasons for corruption is a feeling of obligation towards someone. A personal relationship was thus presented as a factor that enhanced the possibility of corruption. Yet, as with Novikov and Fonvizin half a century later, the tsar did not push the abstraction far enough to direct his criticism against the existence of personal relations between the superiors and the subordinates.

The personal character of the hierarchical work relationship seems to have been experienced as something almost as normal as the necessity to eat; that is, not something commented on in qualitative terms, when it is not associated with gluttony or starvation.

In the beginning of the 19th century, when the Russian elite finally engaged in theoretical reflexion about the internal functioning of government, it was eager to criticise the normative tools of the type introduced and advocated by Peter I, pointing out their manifest low efficiency. In the Zapiska o drevnei i novoi Rossii (Memoir on Ancient and Modern Russia, 1811) addressed to Alexander I, Nikolai Karamzin defended a model based on a virtuous minister's discretion. He summed up his views by saying, in a strikingly unbureaucratic spirit, that ‗a useful ministry is not organized by writing a Regulation, but by forming good ministers' capable of ‗handling the personnel.' 18 I have designed this short demonstration to highlight a fact that the drawbacks of the standard interpretive approach of the work relationship in the 18th-century Russian government are due in a large measure to the inadequacy of the current conceptual language that operates by oppositionspersonal/impersonal, formal/informal, patron-client/bureaucraticas well as by such notions as ‗professional'. The emergence of a more adequate conceptual framework is hardly possible without developing a different language, moulded by the specificity of the epoch under consideration, rather than imposing a logic proper to the historian's own time. That is why the last part of this paper introduces a discussion about the meaning of some of the very basic notions of the history of the administration. For example, 18 N.M. Karamzin, Zapiska o drevnei i novoi Rossii v ee politicheskom i grazhdanskom otnozhenijakh, Moscow, 1991, pp. 61, 99, 100. the analytical term of government as a set of practical actions needed to exercise a political rule over a society as well as the historical term ‗sovereign's service' (sluzhba gosudareva).

Levying taxes, rendering justice and so forth are government actions under any political regime. But, in different historical contexts, the agents who execute these actions on different functional levels can have various statuses. In Muscovite and Petrine Russia, these people were drawn from three large categories. The first one was the political elite, entirely covered by the contemporary notion of the ‗Sovereign's Court' (Gosudarev dvor). 19 As is well known, the Sovereign's Court was organized in a pyramid of grades, granted by the tsar on a hereditary basis with an additional consideration of merit, the grades ranging from boyar down to the d'iak (from the Greek diakonos, or ‗servant', that in Russian came to mean a prince's or tsar's secretary). The second category consisted of literate men having obtained a status of pod'iachii (under-secretary), and who did most of the paperwork in the country. And finally, the execution of certain government actions, such as the collection of taxes, was systematically imposed upon a third category, the tax-payers, who elected special representatives on an annual basis. These people were often illiterate and had to hire under-secretaries to assist them.

As a group, the members of the Sovereign's Court were characterised by a diversity of statuses, contrasted by a relative unity of social fibre: they were all 19 Praviashchaia elita Russkogo gosudarstva, IX -nachala XVIII v.: Ocherki istorii, ed.

A.P. Pavlov, St Petersburg, 2006. hereditary landed service nobility, dividing their time between living on their estates and accomplishing various services to the tsar, court, military or government, with very little or no specialisation. In their turn, the under-secretaries were distinguished by a status unity, contrasted by a great social diversity. They came from almost every social group, from peasants to the inferior grades of the Sovereign's Court, though heredity, of course, was strong. The under-secretaries preserved family and other ties with their original milieu. And one should not imagine that all of them presented a profile of a full-time government official. The traditional historiography has obscured an important fact that many of them lived as much or even not so much from the sovereign's service, as from exploiting land, small industrial enterprises such as alcohol-brewing or milling, from money-lending and notarial work, some of them successfully combining several of these activities. Some historians have considered it possible to unite these two categories under the notion of the ‗sovereign's servitors' for any historical period, though it is well known that the original term was applied exclusively to the members of the Sovereign's Court, and did not comprise the under-secretaries. This fundamental assumption on one hand, as well as the continuity of the political notion of service, and the equivalence of the basic government actions through the time on the other, explain the recurrent idea of a continual existence of bureaucracy in Russia from the 16th century: the ‗service bureaucracy' of the 16th and 17th centuries would have muted to the ‗noble's bureaucracy' of the 18th century, that in its turn would have evolved to the ‗classless bureaucracy' during the 19th century.20 I suggest that there is no reason to assume social, cultural and structural continuity of government action between the Muscovite realm and the Russian Empire, for we should consider the effect of a cluster of heterogeneous factors that imposed change on the nature of the work relationship in government under the reign of Peter I. The range of practical government actions that were performed by the under-secretaries and the elective representatives of the tax-paying population was larger than the notion of the sovereign's service, initially limited to the feudal military service. The political responsibility of tax collection vested in members of the Sovereign's Court was sovereign's service, but the technical task of collecting taxes was not. Judging a civil case was sovereign's service, but the paperwork engendered by the procedure was not. By contrast, an under-secretary who accompanied the army going on a campaign was rendering as authentic a service as that of a noble horseman in the same army. Duties and tasks of various kinds that required travelling far from one's home, were systematically assimilated into the sovereign's service. Finally, non-lucrative paperwork exacted from the under-secretaries, such as the drawing-up of the accounts or writing reports, had a special status of ‗work on order' (prikaznaia rabota), and was sometimes remunerated in the same way as the service.

The hierarchical work relationship between the members of the Sovereign's Court acting as administrative superiors and the socially ambiguous group of the under-secretaries, the two social strata that the accomplishment of the practical government actions brought into permanent collaboration, took the form of a continual and mostly individual negotiation about the boundaries of the customary notion of the sovereign's service. For a majority of the under-secretaries, it was vital that at least a portion of their paperwork was explicitly recognized as service, for this allowed them to maintain their privileged status, which could otherwise have been lost. It is clear enough that the reconstruction of the processes of change within the hierarchical work relationship in the 18th century must rely on a social history of the two strata in question and on a conceptual analysis of the dynamic interaction between the functional notion of government action and the political, ideological, and cultural notion of sovereign's service. 21 As far as the governing elite is concerned, it has been assumed for a long time that Peter I would have changed the traditional recruitment pool of the upper government personnel, dismissing the old nobility and advancing commoners, which would have brought in new political interests and different backgrounds. Under the additional impact of Peter I's ideology of ‗common good', these would have changed 21 The social history of what is called the governing elite and the bureaucracy of 18th-century Russia is poorly supplied with large-scale empirical studies. Even the most basic prosopographic research covers only the central administration and only the middle of the century, and it is based exclusively on the sources of a general service census, which are not completely reliable, for example, as far as the information on the servitor's economic resources is concerned. This kind of data in particular can be verified by sampling the Russian equivalent of notarial documentation, but, for mysterious reasons, it has never been used for serial studies.

the spirit of the sovereign's service. As is known, the thesis about the commoners finally proved incorrect, for Peter I's government absorbed almost all of the old service families. Nevertheless, the joint effect of Peter's refusing to have either courtiers, or a permanent residence, and his inversion of the elite's traditional sociability led to a collapse of the ancient court society. 22 In 1722, the promulgation of the Table of Ranks gave a new basis to the power structure, since an individual's place in the hierarchy was no longer to depend upon birth (family service history) but predominantly upon his personal service record. In this way, the Table of Ranks suggested the disappearance of a social boundary between the deciders and the performers, the superiors and the subordinates, and it seems evident that this could not but produce profound effects upon the hierarchical work relationship, effects that still need to be elucidated.

On the side of the subordinates, changes were also quite important. Peter I, as is well known, completed the process of replacement of the traditional feudal cavalry by a standing army of a contemporary European type, as well as creating two navies, and it is not surprising that to provide for their needs, the existing government personnel had to be enlarged and reorganized. This reorganization, though, was a social earthquake, comparable in its violence to the one that had ruined the Sovereign's Court. But here the victory does not seem to have fallen on the tsar's side. Peter I wanted a kind of civil standing army, where every agent would have been mobile and easily interchangeable. He did not take into consideration that the under-secretaries functioned, in essence, as local elites. Not only were they not used to being moved from place to place, but their extra-service economic resources, that allowed them to survive in a time when the Crown practically stopped supporting them, could not be exploited in an absentee-owner fashion. Besides, and this is still more important, if the under-secretaries had proved so valuable as local agents, especially as tax collectors, it was certainly related to their hereditary integration to the local life.

Soviet historiography never fully recognized the fact that the so-called bureaucracy made part of the society, interpreting it as a sort of functional superstructure and a pliable tool of the monarchy. In a curious way this view coincided with the treatment that Peter I tried to impose on the under-secretaries, with the difference that the tsar did not actually succeed. The passive resistance he encountered obliged him to resort to having army officers govern both the country and the country's traditional government personnel. The effect of his effortsa topic that has yet to be studied properlyis an important factor in the evolution of the hierarchical work relationship, for it is clear that, for a superior, dealing with subordinates entrenched in local society and more or less economically independent was not the same thing as dealing with ‗civil soldiers'. One might argue that Peter succeeded in destroying only the central government under-secretaries' pattern of life, by transferring the capital from Moscow to St Petersburg, a city of a totally different social and economic tissue. 23 There is little doubt, that for the under-23 O.G. Ageeva, ‗Velichaishij i slavneishii bolee vsekh gradov v svete'grad sviatogo Petra: Peterburg v russkom obshchestvennom soznanii nachala XVIII veka, St Petersburg, 1999; O.E. Kosheleva, Liudi Sankt-Peterburgskogo ostrova Petrovskogo vremeni, Moscow, 2004. secretaries employed in the northern capital it was all but impossible to conserve their old social profile, and the habitual type of the hierarchical work relationship.

Finally, there existed powerful cultural factors of change. Without dwelling on the emblematic beard-cutting and dress-changing episodes, let us consider directly another cultural shift, much more important for our subject, that is the reevaluation of the act of writing, the physical act of manipulating pen and ink and putting words on paper. On the whole, up to Peter I, the physical act of writing remained a socially unprestigious kind of activity. Writing was regarded as just another kind of manual labour. Among the members of the Sovereign's Court many could write, but they never did so in the context of performing their service duties; only the secretaries were bound to write a little when they had to give or transmit orders. 24 As a rule, they put brief phrases on the margin of the documents, taking care to employ a characteristically bad hand. 25 Writing could not but appear as another visible abyss between the superiors and the subordinates, a symbolic boundary that was continually enacted in the everyday hierarchical work relations.

Peter I completely overturned this cultural attitude, as old as Russian history itself. First, there was his personal example for his contemporaries to consider, and it was certainly no less shocking for them to see a tsar write than manipulate an axe in a shipyard. Second, Peter obliged his senior officials to sign all documents emanating 24 G.K. Kotoshikhin, O Rossii v tsarstvovanie Alekseia Mikhailovicha, Moscow, 2000, pp. 45-46. 25 See a collection of samples of secretaries writing in Ol'ga Novokhatko, Razriad v 185 godu, Moscow, 2007, pp. 19-39. from them (as he put it in an edict addressing them, ‗in order that the stupidity of everyone could be evident'). 26 And finally, he put the governing elite in working conditions that often left them no choice as to write documents in their own hand. It is symptomatic that starting from the middle of Peter's reign, the traditional terminological use of the word ‗work' (rabota) for paperwork becomes less frequent, and subsequently disappears. On the whole, I feel confident that these practices were a mighty factor that soon effaced the socially stigmatic association with manual labour from the physical act of writing. From this point of view, subordinates were no longer different from their superiors, and some under-secretaries could have felt a sort of advantage over quite a few superiors who could not write well, when this came to be considered a handicap.

There is no need to stress that this drastic change could not but modify profoundly the hierarchical work relationship. It was a new factor in the mutual judgement between individual superiors and subordinates. More importantly, I suggest that the new cultural status of the physical act of writing contributed to the emergence of a more coherent notion of sovereign's service in relation to government action. Up to Peter I, paperwork in itself was not directly valuable for an undersecretary's career. Such an attitude might be explained by the fact that manual labour could not have been naturally included in the notion of sovereign's service. In practice, a large amount of particularly useful and demanding paperwork allowed one to obtain the tsar's gratification, but there persisted a sort of uneasiness about it, and the under-secretaries' requests for remuneration show that they shared this view to some extent. When Peter I finally overturned this attitude, the accumulated collective consciousness of the utility and importance of paperwork for the government action propelled this activity inside the notion of the sovereign's service. To my mind, this change progressively diminished and finally annulled the importance of individual negotiation about recognizing certain portions of paperwork as the sovereign's service, that structured the traditional hierarchical work relationship. Together with the disappearance of the Sovereign's Court, this change gave a powerful impulse for a subsequent implicit overall integration of the under-secretaries into the service class. The process had not been finished when the Table of Ranks first appeared, but it is clear that the preconditions were set, and that everyone who was not a taxpayer and who participated in government action was finally going to be considered a servant -of the monarch, of the Fatherland, and later, an abstract State.

Bureaus do not necessarily make a bureaucracy, no more than a lifetime occupation invariably forges a professional. For it is not the organizational chart, but the nature of the relations, personalbetween breathing menand socialbetween individuals as social functionswhich is decisive for concluding whether an administrative organ is a ‗proto-Weberian bureau' or a courtier's retinue, a local elite lobby, or perhaps (and why not) just a family. Counting bureaus and employees, drawing organizational charts, compiling basic prosopographical data, reciting the regulations and cataloguing the procedures, all of the useful and necessary as well as venerable methods of the traditional historiography of the Russian Ancien Régime administration, will continue to impose upon us anachronistic ideas about its character as long as the work relationship has not received sufficient attention as one of the central questions of the history of government. In accordance with some other essays in the present volume, this article shows that focusing on personal loyalties remains a virtuous historiographical exercise as long as preference is given to careful investigation of the historical context rather than trying to arrive at an abstract definition and a general description of the phenomenon.

6

  To cite just some symbolic examples: S.M. Troitskii, Russkii absoliutizm i dvorianstvo v XVIII veke: formirovanie biurokratii, Moscow, 1974; Russian Officialdom: The Bureaucratization of Russian Society from the Seventeenth to the Twentieth Century, eds. Walter Pintner and Don Karl Rowney, London and Basingstoke, 1980. 7 David Ransel, ‗Bureaucracy and Patronage: The View from an Eighteenth-century Russian

14

  Letter of 11 September 1768, D.I. Fonvizin, Sobranie sochinenii v dvukh tomakh, ed. G.P. Makogonenko, 2 vols,Moscow and Leningrad, 1959, 2, p. 349. 15 David Ransel, The Politics of Catherinian Russia. The Panin Party, NewHaven and London, 1975.

Friedrich Christian Weber, Das veränderteRußland, Frankfurt, 1721, p. 332.

For the notions of manifest and latent functions see: Victor Morgan, ‗Some Types of Patronage, Mainly in Sixteenth-and Seventeenth-Century England', in Klientelsysteme im Europa der Frühen Neuzeit, pp. 91-115 (pp. 104-5).

Satiricheskie zhurnaly N.I. Novikova, ed. P.N.Berkov, Moscow and Leningrad, 1951.

N.F. Demidova, Sluzhilaia biurokratiia v Rossii XVII veka i ee rol' v formirovanii absoliutizma,Moscow, 1987.

Ukase of 7 October 1707 (Zakonodatel'nye aktyPetra I, No 238, p. 196).