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A selective method has been suggested for the synthesis of highly dispersed powders of γ-WO3 (monoclinic) and β-WO3⋅H2O (orthorhombic) by the hydrothermal treatment of aqueous suspensions of peroxotungstic acid in temperature range 70–250°С. The hydrothermal treatment of suspensions of peroxotungstic acid leads to formation of monophase β-WO3⋅H2O at temperature up to 100°С and monophase γ-WO3 at 250°С. The hydrothermal treatment in the temperature range 120–200°С gives two-phase samples of γ-WO3 and β-WO3⋅0.33H2O (orthorhombic syngony). The obtained monophase and two-phase powders have been studied by X-ray powder diffraction, scanning electron microscopy, IR spectroscopy, thermal analysis, and diffuse reflectance spectroscopy.

The synthesis and crystal structure of the first molecular yttrium lactate complex, Y(Lac)3(H2O)2, is reported, where the coordination sphere of yttrium is saturated with lactate ligands and water molecules, resulting in a neutral moiety. In Y(Lac)3(H2O)2, hydrogen bonding between α-hydroxy groups and water molecules allows for the formation of 2D layers. A subtle variation in synthetic conditions, i.e. a slight increase in pH (5.5 instead of 4.5) promoted the formation of a semi-amorphous fibrous material with a presumed chemical composition of Y4(OH)5(C3H5O3)7·6H2O. The flattened fibres in this material are responsible for its good flexibility and foldability.

The article presents the results of an analysis of foreign experience of the legal regulation and the implementation of state support of religious associations in modern secular states in the context of variability of forms and measures of such support, which allow their systematization. The choice of the topic of the article is due to the existence of a complex contradiction in the relationship between the traditional understanding of the secular state characteristic and the practice of providing state support for individual religious denominations, the legally unequal availability of access to support, as well as the risk of actual state interference in the administration of church (denomination) affairs when implementing certain measures of state support. The aim of the research was to substantiate the optimal approach to the definition, legal regulation and implementation of forms and measures of state-confessional support in the modern secular state, prioritizing freedom of conscience and religion and minimizing human rights risks. In order to achieve it, the authors carried out a legalistic analysis of the focused law-making and law-enforcement practices of several foreign countries, which recognize themselves as secular but are distinguished by historical traditions, national, political, social and confessional features; emphasis was placed on systematizing the forms and measures of such support, as well as the most debating aspects of the issue. Also, the following methods of scientific knowledge were used in the research: universal (dialectical, formal logic, systemic, analysis, synthesis, classification) and specific (interpretation of law, comparative law, statistical). The research justifies that the secular nature of the state does not exclude the use of certain forms of support for various confessional communities. However, such support measures should ideally be aimed at ensuring the freedom of conscience and religion of citizens and their associations, rather than the artificial priority of a particular denomination. At the same time, it is necessary to observe the balance of public, collective and individual interests of subjects of confessional relations. The research is based on actual data on the provision of direct and indirect state support to religious associations. However, there are their derivative, alternative, authentic versions, the essence, secular and legal content of which are not always clearly positive. In this regard, an alternative classification of forms and measures of state-confessional support has been carried out – according to the legal content, the results of which allowed assessing the degree of their human rights risk, highlighting permissible and optimal combinations in this aspect. Considering that most of the forms and measures that have been studied are also implemented in Russia, the conclusions and recommendations, presented on the basis of foreign experience, can serve as a basis for an appropriate legislative and law enforcement optimization in the modern Russian state.

Gd-based complexes are widely used as magnetic resonance imaging (MRI) contrast agents. The safety of previously approved contrast agents is questionable and is being re-assessed. The main causes of concern are possible gadolinium deposition in the brain and the development of systemic nephrogenic fibrosis after repeated use of MRI contrasts. Thus, there is an urgent need to develop a new generation of MRI contrasts that are safe and that have high selectivity in tissue accumulation with improved local contrast. Here, we report on a new type of theranostic MRI contrast, namely dextran stabilised, gadolinium doped cerium dioxide nanoparticles. These ultra-small (4–6 nm) Ce0.9Gd0.1O1.95 nanoparticles have been shown to possess excellent colloidal stability and high r1-relaxivity (3.6 mM−1 s−1). They are effectively internalised by human normal and cancer cells and demonstrate dose-dependent selective cytotoxicity to cancer cells.

Objective: to study the relationship of behavioral RF of CVD with arterial stiffness and daily dynamics of central aortic pressure in women of different age groups. Materials and methods: 161 women were examined, which were divided into 3 groups: 1st group – 52 young women from 18 to 30 years old (23.8±5.3 years old); 2nd group – 54 women from 31 years old until menopause (41±5.9 years); Group 3 – 55 women in the postmenopausal period (55.4±5.8 years). All volunteers underwent questionnaires, anthropometry, the study of arterial stiffness with the Doppler method and the method of volume sphygmography, daily monitoring of blood pressure with an assessment of vascular stiffness and central aortic pressure. Results : the strongest relationship between smoking and arterial stiffness was detected in the 3rd group, with the number of cigarettes per day being more important. Moderate alcohol consumption in group 1 is associated with an increase in the rate of increase in blood pressure in the aorta (dp / dt) max (R = 0.35, p = 0.01) and an improvement in the daily dynamics of central and peripheral pressure. A strict limitation of the caloric content of the consumed products is associated with a decrease in the carotidfemoral velocity of the cfSPV pulse wave (R = -0.2, p = 0.01) and an improvement in the characteristics of the reflected wave in all groups. Only in the 1st group, the use of 400 grams or more vegetables and fruits per day is associated with an improvement in rigidity. Low physical activity in the 3rd group is associated with an increase in the Weissler coefficient (R = 0.28, p = 0.04) and AASI (R = 0.29, p = 0.03). Conclusion : behavioral RF of CVDs are interrelated with various indicators of arterial stiffness and changes in central and peripheral pressure in women of different ages. The most significant indicators can be used as markers for the development of subclinical changes in the vascular wall in women, depending on their risk factors in order to start preventive measures in a timely manner.

Background. General and abdominal obesity is widespread among women in the Russian population. The relationship between obesity and arterial stiffness, as a predictor of the development of cardiovascular diseases, in women of different ages remains unclear. Aims: to study the relationship between obesity and arterial stiffness and dynamics of central aortic pressure in women of different ages with preserved and lost reproductive function. Methods. 161 women were examined and divided into 3 groups. Two groups included women with preserved reproductive function: group 1 consisted of 52 young women aged from 18 to 30 years (23.8 5.3 years); group 2 included 54 women aged from 31 years to the menopause (41 5.9 years). Group 3 included 55 postmenopausal women (55.4 5.8 years). All the women underwent a clinical examination with anthropometry; questioning; 24-hour monitoring of the dynamics of blood pressure with measuring the indicators of arterial stiffness and daily aortic central pressure; determination of the carotid-femoral pulse wave velocity (cfPWV); study of vascular stiffness by volume sphygmography. Results. The anthropometric data in groups 2 and 3 were comparable in terms of the prevalence of general obesity (GO). Abdominal obesity (AO) was detected in 19.2% of the 1st group; 51.9% of the 2nd and 76.4% of the 3rd group. In the 1st group AO had the strongest correlation with the aortic pulse wave velocity PWVao (R = 0.41, p = 0.002) and the corrected to HR75 augmentation index Aixao (R = 0.38, p = 0.005). In the 2nd group AO correlates with cfPWV (R = 0.4, p = 0.003); GO with PWVao (R = 0.38, p = 0.005) and aortic cardio-ankle vascular index CAVIao (R = 0.48, p = 0.001). In the 2nd group AO and GO are also interconnected with the central and peripheral pressure. In the 3rd group AO correlates with PWVao (R = 0.33, p = 0.01), cfPWV (R = 0.32, p = 0.02); GO with the index of the double product IDP (R = 0.36, p = 0.01). Conclusions. Obesity, especially its abdominal type, is an important factor determining the development of vascular wall stiffness in women of the reproductive age. It is necessary to conduct a comprehensive assessment of arterial stiffness and daily dynamics of central aortic pressure in women of all ages, suffering from obesity and, first of all, its abdominal type, in order to early diagnose subclinical changes in the vascular wall and central hemodynamic disorders.

In spite of the wide application of nanodisperse tungsten oxide (from photo- and electrochromic devices to biomedical materials), its physicochemical properties were studied insufficiently. In this work, we have performed a comparative analysis of photochromic and photocatalytic properties of polyvinylpyrrolidone-stabilized tungsten oxide nanoparticles prepared by ion exchange and precipitation from sodium tungstate solution. Reversible UV-induced reduction of Methylene Blue dye in the presence of photochromic tungsten oxide sol has been shown, the dependence of photochromic properties of tungsten oxide sols on sodium cation concentration in solution has been revealed.

Nanocrystalline hafnium dioxide has been synthesized by hydrothermal treatment of X-ray amorphous hydrated hafnium dioxide in distilled water at 120–260°C for 1–7 days and in the presence of NaCl and NaOH as mineralizing agents. The size of HfO2 crystallites has been shown to be determined by the temperature of hydrothermal treatment and the type of mineralizing agent. The size of HfO2 crystallites obtained in alkaline medium is by 2–3 times smaller than that for HfO2 crystallites obtained in neutral medium and constitutes ~8 nm. Dispersing of nanocrystalline HfO2 obtained by hydrothermal treatment in water in the presence of dextrane and poly(vinylpyrrolidone) under exposure to ultrasound leads to preparation of stable sols of nanocrystalline HfO2.

The reaction of divanadium pentoxide and N,N-dimethylformamide under hydrothermal conditions at 180–250°C has been studied. Depending on the temperature and duration (1–7 days) of hydrothermal synthesis, the reaction of V2O5 and (CH3)2N–CHO has been shown to lead to single-phase powders of [(CH3)2NH2]V3O7, VO2(D), and V2O3 in a yield up to 50–85%. Variation of initial pH value of reaction mixtures within 0.5–3.7 and molar ratio V2O5 : (CH3)2N–CHO in the range 1 : 5–1 : 50 provides no considerable effect on the phase composition of synthesis products.

The structure of SiO2-based materials obtained by hydrolysis of tetraethoxysilane and subsequent drying of SiO2 lyogels at temperatures from 85 to 265°C has been analyzed in detail. It has been found that drying conditions have no marked effect on the specific surface area of SiO2, which constitutes ~1000 m2/g in all cases. Average pore size and specific pore volume monotonically increase with drying temperature, the contribution of large mesopores (>20 nm) into total material porosity rises at high drying temperature. Drying temperature has a considerable effect on the degree and character of individual SiO2 particles aggregation.

Thermodynamic properties (heat capacity Cp, entropy S°, enthalpy change ΔH° and reduced Gibbs energy ΔΦ°) of crystalline WO3 in a temperature range of 80–1256 K were refined using two complementary calorimetric methods, namely differential scanning calorimetry and adiabatic vacuum calorimetry. Enthalpy changes during a number of successive phase transitions in WO3 were calculated from differential scanning calorimetry data in both heating and cooling regimes and compared to previously reported values. For the first time, enthalpy changes for the orthorhombic to monoclinic and monoclinic to tetragonal high-temperature phase transitions in WO3 were estimated.

This study shows excellent NO2-sensing properties of tungsten oxide nanoparticles, prepared using a facile procedure which includes dissolution of metallic tungsten in hydrogen peroxide with subsequent low-temperature (400 ?C) heating. We also conducted a thorough literature survey on sensor properties of tungsten oxide prepared by various means and found that the sensor response towards NO2 registered in this work achieved the highest level. The most intriguing feature of the material obtained was a highly reproducible sensor signal at room temperature which was more than 100 times higher than any reported previously for WO3. The probable reason for such high sensor response was the presence of two WO3 polymorphs (-WO3 and h-WO3) in the material synthesized using a peroxide-assisted route. In order to further investigate synthesizedWO3 materials, sophisticated experimental (XRD, SEM, TEM, BET) and theoretical (B3LYP, HSE) methods have been used, as well as resistance and sensor response measurements at various temperatures.

Purpose: In article on the basis of the formal legal analysis of the national legal system and the international jurisprudence the key principles of state legal regulation of the confessional relations in the sphere of the general education are distinguished; the need of their addition and unification at the national level for the purpose of providing the balanced ratio of public and private interests in the context of providing the integrated rights and personal freedoms is demonstrated. Methodology: In work, various general scientific methods, acceptances, and methods of logical knowledge are used: analysis and synthesis, system, formal and logical, formal legalistic. Result: It should be emphasized that the process of legal regulation of the modern secular state is not enough to adhere to the principle of religious neutrality and minimize the amount of religious component in the public spheres of life of the individual and society, including the system of General education. Currently, such a state is designed to ensure a balance between public and private interests in this area. Applications: This research can be used for universities, teachers, and students. Novelty/Originality: In this research, the model of Legal Regulation of Interreligious Relations in the Field of General Education: The Ratio of Public and Private Interests is presented in a comprehensive and complete manner.

The ability of cerium(IV) hydrogen phosphate Ce(PO4)(HPO4)0.5(H2O)0.5 to adsorb radionuclides was studied. The degree of sorption from aqueous solutions exceeds 95% at pH > 7 for Np(V), at pH > 9 for Sr(II), at pH > 5 for Am(III) and U(VI), and at pH > 2 for Th(IV). The radionuclides are rapidly and quantitatively leached from the sorbent surface in acid solutions; i.e., the sorption is reversible.

The purpose of the article: This was aimed at conducting a system analysis of the forms of interaction between religious organizations and modern states implementing the secular model regarding the regulation of religion component in the field of general education.Materials and methods: Various general scientific methods and methods of logical cognition were used in this study including analysis and synthesis, systemic, formal-logical. The subject under study was investigated by the use of a formal legal method and content analysis.Results of the research: The necessity with respect to the role of the state to guarantee activities of confessional educational organizations implementing general education programs (their components) in legal, organizational, methodological and financial spheres were substantiated. It was proposed to unify the approach according which the state regulating the participation of religious organizations in the field of general education in order to ensure equal opportunities for students in implementation of freedom of conscience and religion. Applications: This research can be used for the universities, teachers, and students. Novelty/Originality: In this research, the model of investigation of the role of religious organizations in system of general education: forms of state-confessional interaction is presented in a comprehensive and complete manner.

Reversible photochromic hybrid organic–inorganic films containing nanocrystalline cellulose as a matrix and tungsten oxide as a photochromic component (CNC/WO3) were obtained via a simple and quick solvent casting method. The films were studied by scanning electron microscopy, together with element mapping, FT-IR spectroscopy and X-ray diffraction, confirming successful incorporation of WO3 nanoparticles into a nanocellulose matrix. Thermal analysis data indicated that the modification of a nanocellulose matrix with WO3 increases its thermal stability. The CNC/WO3 films showed a quick coloration-bleaching transition with good reversibility within 20 min, without notable degradation of photochromic properties after 10 cycles. The synthetic method proposed allows for scalable preparation of highly efficient low-cost WO3-based photochromic materials.

Currently, women-specific risk factors for cardiovascular diseases (CVD) are of particular importance, one of which is hypertensive disorders during pregnancy (HDP). The effect of hypertensive disorders on the formation of arterial stiffness as a predictor of CVD development remains insufficiently studied. Aim. To study the relationship of indicators of arterial stiffness, risk factors and metabolic changes with the presence of HDP in the history of women of different age groups. Materials and methods. The study included women aged 30 to 65 years, with one or more risk factors of CVD, which were divided into two groups: 1st - with preserved menstrual function and 2nd group - in the postmenopausal period with the presence or absence of HDP. All patients underwent daily blood pressure monitoring with determining the dynamics of central arterial pressure, determining the velocity of the pulse wave from the carotid to the femoral arteries, non-invasive determination of vascular stiffness indicators using the volume sphygmography method. Results. 90 women were examined. The first group consisted of 45 women (mean age 41±5.9 years); the second group - 45 women (mean age 55.3±5.8 years). In both groups, women with HDP are more likely to have burdened CVD heredity (p=0.02). In the 1st group with HDP, the average body weight and body mass index were significantly higher (p=0.02); menstrual disorders occurred more than twice as often (p=0.01) than in women without HDP. In the 2nd group with HDP abortions were more frequent (p=0.05) in history. In the 1st group with HDP, a significantly higher augmentation index AI (p=0.01); the average value of the average daily rate of the pulse wave in the aorta was also exceeded (11.7 m/s), which is 0.8 m/s higher than in women without HDP (p=0.02). Conclusion. A change in the AI and the average daily pulse wave velocity in the aorta, along with the presence of CVD risk factors and hormonal and metabolic disorders, are early markers of subclinical damage to target organs in women of reproductive age with a history of HDP.

The development of advanced composite biomaterials combining the versatility and biodegradability of polymers and the unique characteristics of metal oxide nanoparticles unveils new horizons in emerging biomedical applications, including tissue regeneration, drug delivery and gene therapy, theranostics and medical imaging. Nanocrystalline cerium(IV) oxide, or nanoceria, stands out from a crowd of other metal oxides as being a truly unique material, showing great potential in biomedicine due to its low systemic toxicity and numerous beneficial effects on living systems. The combination of nanoceria with new generations of biomedical polymers, such as PolyHEMA (poly(2-hydroxyethyl methacrylate)-based hydrogels, electrospun nanofibrous polycaprolactone or natural-based chitosan or cellulose, helps to expand the prospective area of applications by facilitating their bioavailability and averting potential negative effects. This review describes recent advances in biomedical polymeric material practices, highlights up-to-the-minute cerium oxide nanoparticle applications, as well as polymer-nanoceria composites, and aims to address the question: how can nanoceria enhance the biomedical potential of modern polymeric materials?

Cerium oxide nanoparticles (nanoceria) are regarded as one of the most promising inorganic antioxidants for biomedical applications. Considering nanoceria as a potential therapeutic agent, we aimed to develop a robust system for its intracellular delivery using layer-by-layer polyelectrolyte microcapsules. We have shown that citrate-stabilized cerium oxide nanoparticles can be effectively incorporated into the structure of polyelectrolyte microcapsules made from biodegradable and nonbiodegradable polymers. The structure and morphology of synthesized microcapsules were investigated and analyzed using confocal laser scanning microscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and UV/vis spectroscopy. Results of experiments in vitro on B50 neuroblastoma cells confirmed nanoceria delivery into the cell while maintaining their antioxidant properties. The results presented confirm polyelectrolyte microcapsules to be an efficient intracellular delivery system for therapeutic nanoparticles.

The article discusses the company’s oil and gas investment opportunities. Abroad, venture capital companies provide opportunities for direct investment in the growing oil and gas industry. With extensive experience in developing horizontal oil and natural gas fields, venture capital firms use long-term industry knowledge to provide their partners with high-yield investment opportunities that allow them to diversify their investment portfolios and ensure a stable cash flow while simultaneously getting the right to benefits and significant tax. Venture companies are constantly working to reduce the risks associated with oil and gas projects by partnering with the best operators in the industry. This article discusses the company’s oil and gas investment opportunities. Abroad, venture capital companies provide opportunities for direct investment in the growing oil and gas industry. With extensive experience in developing horizontal oil and natural gas fields, venture capital firms use years of industry knowledge to provide their partners with high-yield investment opportunities that allow them to diversify their investment portfolios and ensure stable cash flow and simultaneously entitle benefits and significant tax. Venture companies constantly working to reduce the risks associated with oil and gas projects by partnering with the best operators in the industry.

This article examines the issues and problems of ecology and climate change that concern an increasing number of people. In Russia, in particular, the attention of Russian companies and the government to the problem is increasing. Green finance is a tool that allows for a carbon transition to a green economy, providing extra-budgetary sources of funding for projects that provide this transition. To facilitate the transition of business to the principles of sustainable development, the Ministry of Industry and Trade of the Russian Federation has supplemented the compensation program for green bonds with green loans, and banks are developing new mechanisms to provide companies with a clear tool for cofinancing environmental projects.

Aims and objectives. Identify the priority features of the formation of the most significant diseases in women with the focus on the determination of disease markers and their development triggers. Materials and methods. 408 healthy women from the students and employees of The Moscow State University of Medicine and Dentistry named after A.I. Yevdokimov took part in the research. All the women completed a questionnaire, which was elaborated by the researchers. The survey contained questions designed to identify major risk factors for cardiovascular diseases and explore dietary and physical activity habits, bad habits and diseases, gynaecological status. Results. All the participants were divided into 4 groups. The 1st group included 157 female subjects under the age of 24; the 2nd was represented by 113 women above the age of 25 who reported pregnancy and birth in their case history; the 3rd group was formed by non-parous 74 women of the same age and the 4th one consisted of 64 postmenopausal women. Complaints of dyspnea and unpleasant feelings in the region of the heart which were not caused by physical exercise were found, for the most part (р=0,001), in the women of the fourth group (73 % opposed to 36 % of cases in the 1st group). 18.4% of the interviewed smoked and were mainly found in the groups of reproductive-age women. Worth noting that lack of physical activity was reported in the groups. Inactivity was found predominantly (48 %, р=0,001) in the volunteers of the 4th group. A third of the women from that group noted the symptoms of physical activity intolerance represented by dyspnea and weakness. 41,4 % of the female subjects (n=169) had chronic conditions: most of them were gastrointestinal diseases with the prevalence of gastritis (36,5 %). The analysis of the gynaecological status of the interviewed allowed to discover ovarian dysfunction in 26,8 % of the interviewed women. 52 % of the women from the 1st group suffered from premenstrual syndrome. 14,7 % of the interviewed had a premature birth. 11,7 % of the women had undergone C-section. Pregnancy complications were reported in 15,4 % of the interviewed; 11,4 % of the cases were pregnancy losses. 28 % of the representatives of the 4th group reported surgical menopause. This group demonstrates the proven (р=0,001) increase of body mass index, high arterial pressure, hot flushes, insomnia. Conclusion. The conducted research allowed discovering significant negative impacts of smoking, low physical activity, unhealthy diet, especially, in the group of reproductive-age women. Hormonal disorders, pathology in pregnant women found in the groups of young subjects as well as high rate of somatic diseases in healthy women require an in-depth study of the identified risk groups.

A novel method was suggested for removing Th(IV) and other radionuclides from liquid media. The method consists in formation of the sorbent, fibrous cerium(IV) hydrogen phosphate, directly in the aqueous solution. The sorbent shows the highest performance in the removal of Th(IV). The sorbent can also serve as a host material for the subsequent Th(IV) disposal.

The dielectric properties of nanocrystalline tungsten oxide are studied in the temperature range of 223–293 K and in the frequency range ν = 10–2–106 Hz. Powders of WO3 with particle sizes of 110, 150, and 200 nm are prepared by the heat treatment of ammonium paratungstate at various temperatures. It is established that the frequency dependences of the conductivity for all samples increase with an increase in frequency, while the polarization characteristics e'(ν) and e"(ν) decrease. It is found that the frequency dependences of the conductivity are described by a function of the form ν s with an index in the range of (0.83–0.90) ± 0.01, which is characteristic of the “hopping” mechanism of charged-particle motion (complexes) over localized states confined by potential barriers and structural defects.

Nanocrystalline manganese dioxide have been prepared by hydrothermal microwave treatment of mixed solutions of potassium permanganate and 2,4,6-triamino-1,3,5-triazine (melamine) in pH range 0.5–3. Phase and chemical composition and morphology of the samples was studied by XRD, Raman spectroscopy, and SEM. Conditions (solution pH and temperature) for the formation of single phase MnO2 powders (α-MnO2, γ-MnO2, δ-MnO2, and δ*-MnO2) under hydrothermal microwave treatment were determined.

Cerium oxide nanoparticles (nanoceria) are regarded as one of the most promising inorganic antioxidants for biomedical applications. Considering nanoceria as a potential therapeutic agent, we aimed to develop a robust system for its intracellular delivery using layer-by-layer polyelectrolyte microcapsules. We have shown that citrate-stabilized cerium oxide nanoparticles can be effectively incorporated into the structure of polyelectrolyte microcapsules made from biodegradable and nonbiodegradable polymers. The structure and morphology of synthesized microcapsules were investigated and analyzed using confocal laser scanning microscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and UV/vis spectroscopy. Results of experiments in vitro on B50 neuroblastoma cells confirmed nanoceria delivery into the cell while maintaining their antioxidant properties. The results presented confirm polyelectrolyte microcapsules to be an efficient intracellular deliver...

A novel approach to the analysis of the electrorheological effect is proposed, based on the expansion of dimensionless relative shear stress as function of electric field strength in the power series $$ {\tau}_{\mathrm{rel}}=\frac{\tau_E}{\tau }=1+\frac{\alpha }{\tau }E+\frac{\beta }{\tau }{E}^n $$ . The application of this approach to investigation of the electrorheological effect in suspensions of isotropic and needle-like CeO2 nanoparticles in polydimethylsiloxane has revealed that the polynomial coefficients can be judged as a measure of the efficiency of transformation of electrical energy into mechanical energy. The values of α and β coefficients depend on the shape and concentration of filler particles, as well as on the shear rate. The value and the sign of these coefficients determine both the magnitude of the electrorheological effect and the type of dependence of the shear stress (linear or power law) on the strength of the electric field. It has been shown that the values of α and β coefficients for the electrorheological fluids with needle-like particles are greater than for fluids with isotropic particles (at the same concentration of suspensions), which is associated with the different polarization of particles in the applied electric field.

A new facile method is proposed for the preparation of aqueous sols of highly crystalline tungsten trioxide with a particle size of 60–150 nm, containing no organic stabilizers/surfactants. These sols possess high sedimentation stability, which is quite unusual for inorganic colloidal systems containing relatively large particles, with a rather high density (ρ c(WO3) = 7.3 g/cm3). The method is based on the thermal decomposition of ammonium paratungstate, followed by dispersing the resulting powders in water under ultrasonic treatment. Thermal decomposition of ammonium paratungstate, and the composition and structure of the resulting tungsten trioxide and its aqueous dispersions, were investigated with thermal analysis combined with the mass spectrometry of gaseous thermolysis products, powder X-ray diffraction, scanning electron microscopy, low-temperature nitrogen adsorption, IR spectroscopy and dynamic light scattering. It has been demonstrated that the high sedimentation stability of WO3 results from electrostatic stabilization, which might be caused by the formation of tungstic acid on the surface of WO3 particles when they come into contact with water. The nanocrystalline WO3 obtained can be used to produce gas sensors for ammonia.