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The redox transformations in a conducting polymer film on a platinum electrode were studied by Raman spectroelectrochemistry at fixed potentials depending on the incidence angle of the laser beam. Raman scattering was excited with a laser at a wavelength of 532 nm. Polyaniline (PANI) and its complex with poly-2-acrylamido-2-methyl-1-propanesulfonic acid (PAMPSA) were used as a conducting polymer. The polymer films were deposited by potentiostatic electropolymerization. By varying the incidence angle of the beam it is possible to obtain a Raman spectrum without the bands of the substrate overlapping with the characteristic bands of the polymer to minimize the substrate effect on the interpretation of the results. A comparative study of the electrochemical oxidation/reduction of the PANI films taking into account the detected angular dependence showed that, unlike the PANI films obtained in the presence of hydrochloric acid, the films of the PANI-PAMPSA complex retained the radical cation state of PANI in the range of the cathodic potentials. The reason for this is the presence of a nonconductive polymer acid phase in the PANI-PAMPSA film, as a result of which the percolation threshold of the conducting domains of PANI appears at less cathodic potentials, hindering further extraction of the positive charge during the film reduction. In addition, the use of this approach can significantly improve the accuracy of determination of the threshold potential of the leucoemeraldine-emeraldine transition.

The results of a study of some ways to improve spectroscopy characteristics of the CdZnTe quasi-hemispherical detectors when working in high gamma radiation fluxes are presented. It was shown that the use of IR illumination with a wavelength of 1050 nm or 1200 nm or at slight warm-up of the detector to +30°C … +40°C can significantly improve spectroscopy performance of the CdZnTe detectors of size 3.5 mm × 3.5 mm × 1.75 mm when operating in a tested gamma-radiation field with a dose rate up to 590 mGy/h.

Polyaniline (PANI) films were prepared by electrochemical polymerization of aniline on Pt-electrode in aqueous medium in the presence of polymeric sulfonic acids distinguished by different flexibility of the polymer chain: (1) poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA, flexible chain); (2) poly(4-styrenesulfonic acid) (PSSA, flexible chain), (3) poly-4,4′-(2,2′-disulfoacid)-diphenylene-iso-phthalamide (i-PASA, semi-rigid chain); and (4) poly-4,4′-(2,2′-disulfoacid)-diphelylene-tere-phthalamide (t-PASA, rigid chain). Raman spectroelectrochemical studies using 532 nm laser excitation were carried out in aqueous HCl. The conventional HCl-doped PANI films were also studied for comparison. The results allowed one to distinguish the potential-dependent vibrations belonging to PANI and potential-independent vibrations belonging to the polyacids. In addition, amide C=O vibration was separated in the spectra by comparing the results for amide-containing (PAMPSA, i-PASA, and t-PASA) and amide-free (PSSA) PANI-polyacid complexes. The films of PANI-polyacid complexes demonstrated increased content of radical cation moieties at low potentials compared to PANI–HCl films.

Conditions that allow obtaining stable aqueous dispersions based on conducting polymer, polyaniline, as a result of aniline polymerization in the solution of polymeric acid at its twofold excess were determined. The electrical and optical properties of polianiline obtained under these conditions remain invariable during at least 2 years due to the absence of aggregation of conducting polymer particles that are separated by macromolecules of polymeric acid. Data obtained by EPR spectroscopy, SEM, UV–visible spectroscopy, and IR spectroscopy prove these results.

Composites of polymers with conjugated chain structures, polyaniline and polypyrrole, are used as sorbents for human and bird flu viruses. Sorption properties of the composites are compared to characteristics of the initial polymers. It is shown that polymer composites containing metallic silver nanoparticles possess sorption activity, similarly to their composites with polyethylene and the initial polyaniline and polypyrrole. The introduction of silver into polypyrrole resulted in an enhancement of the sorption activity as compared to that of the initial polymer. Nontoxic metal—polymer composites reduce considerably the concentrations of human flu viruses A(H1N1), A(H3N2), and B and bird flu virus A(H5N2) with different structures of surface virion proteins in aqueous media at a sorbent concentration of 10–20 mg/mL in the temperature range from +4 to 37°C.

A Passive Gamma Emission Tomography system (PGET) [1] was developed for the IAEA Safeguards for verification of irradiated nuclear fuel assemblies (SFAs). In 2015-2016 PGET underwent significant re-design and its performance has been tested on multiple SFA types. The re-designed PGET features the functionality of traditional non-destructive assay systems commonly used for spent fuel verification: total neutron counting (Fork Detector, FDET), medium-resolution gamma spectrometry (Irradiated Item Attribute Tester, IRAT or Spent Fuel Attribute Tester, SFAT) and spent fuel assembly’s lattice image (Digital Cherenkov Viewing Device, DCVD). Two 10B neutron detectors and one-hundred-seventy-four collimated CdZnTe detectors are grouped in two arrays on a rotary baseplate inside a watertight stainless steel enclosure. A SFA is lowered through the center of the enclosure and held stationary to perform an underwater measurement. Detector arrays are then rotated on a baseplate in the horizontal plane around vertical axis of symmetry to obtain gamma sinogram and neutron count data simultaneously, typically in 3-5 min per assembly. Additionally, medium resolution spectra from all gamma detectors can be collected and recorded. Functional, technical and operational performance of the PGET was tested at four nuclear reactors on mockup, PWR, BWR and WWER-440 SFAs. Measurements have been performed on fuel with burnup in the range 5.7-58GWd/tU and cooling times from 1.9 to 27years. Lateral pin structure of the SFAs could be reconstructed for any tested fuel design in the above range of cooling times and burnups. Missing or replaced pins in all fuel types could be clearly visualized in the reconstructed images; spectrometric information (134Cs/137Cs peak ratio) and neutron counting rates were found to be consistent with declared fuel radiation history. This paper describes details of the PGET hardware and electronics and presents some results of performance evaluation.

The nucleation of the solid phase of interpolymer complexes of polyaniline (PAn) during electropolymerization of aniline on highly orientated pyrolytic graphite in aqueous solutions of hydrochloric acid and polymer sulfoacids, which differ in the rigidity of the polymer framework, was studied in situ by atomic force microscopy. The rigidity of the polyacid chain, which determines possible changes in its conformation in solution and its ability to adapt its conformation to that of the rigid conjugated PAn macromolecule, directly affects the shape and growth rate of the nuclei of solid phase of PAn and the film morphology at the early stages of electropolymerization. The rigid-chain and semirigid-chain polymer acids, which have the conformation of an elongated or slightly bent rod in solution, determine the conformation of the interpolymer complex nuclei. In contrast, in the presence of flexible-chain polyacids, the process is mainly controlled by the conformation of PAn macromolecules.

The electrodeposition of polyaniline (PANI) was carried out in potentiostatic, galvanostatic and potential sweep regimes in the presence of water-soluble polymeric sulfonic acids with different structure. The course of polymerization was traced by chronoamperometry, chronopotentiometry, cyclic voltammetry and in situ AFM measurements. The rigidity of the polyacid backbone, the distance between sulfonic groups on the backbone, the length and rigidity of the side chains containing sulfonic groups were shown to affect the onset potential of aniline oxidation, the character and the rate of the initial stages of PANI/polyacid film growth. AFM data indicated that the structure of the polyacids has a direct influence on the shape of PANI “nuclei” and the morphology of the film in the early stages of the electropolymerization. The obtained films were characterized by UV-Vis-NIR spectroscopy and cyclic voltammetry.

Phase transformations in ZrO2 + xSc2O3 solid solutions (6.5 < x < 11 mol%) at sintering of ceramics obtained from nanopowders produced by laser evaporation of the ceramic targets have been studied. The Sc2O3 concentration increasing from 6.5 to 11 mol% is accompanied by the sintering temperature decreasing and the average grain size growth from 130 nm to 760 nm. At concentration of about 7 mol% Sc2O3 an abrupt increase of the average grain size and electric conductivity is observed. The sinterability of the ZrO2 − хSc2O3 ceramics is affected by the prehistory of nanopowders preparation. The characteristics of ceramics obtained from nanopowders evaporated from the targets based on (ZrO2 + xmol% Sc2O3) mixture and on the (ZrO2 − 11mol% Sc2O3) solid solution significantly differ, namely, in the latter the sintering temperature is markedly lower and the shrinkage rate is higher. Besides, its average grain size is substantially lower and the conductivity is higher.

We demonstrate that the solvent-free mechanochemical method, previously used for the synthesis of polyaniline (PANI) protonated with low molecular weight inorganic acids, can be extended to the preparation of conductive, all-polymeric PANI/polyacid molecular composites. Two polymeric sulfonic acids differing in their chain rigidity were selected as PANI protonating agents, namely: poly-(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA, flexible backbone polyacid) and poly(p,p′-(2,2′-disulfonic acid)-diphenylene- tere -phthalamide) ( t -PASA, rigid backbone polyacid). Spectroscopic (UV–vis–NIR, FTIR, EPR), morphological, structural (TEM), electrochemical and spectroelectrochemical properties of the mechanochemically prepared molecular composites were compared with those determined for their analogs synthesized by oxidative polymerization in aqueous solution. The mechanochemically synthesized molecular composites show a characteristic layer-type morphology, distinctly different from that observed for the composites prepared chemically in aqueous solutions. UV–vis–NIR and FTIR spectroscopy clearly indicate better polaron delocalization in the mechanochemically prepared samples. These results are in line with those obtained in ESR, electrochemical and spectroelectrochemical investigations unequivocally showing better charge carrier delocalization in the mechanochemically prepared composites. The measured dc-conductivity of the mechanochemically prepared samples is 24 mS/cm and 31 mS/cm for PANI/PAMPSA and PANI/ t -PASA, respectively.

Synthesis, ionic conductivity, and ageing behavior of [ x Y 2 O 3 –(10 − x ) Sc 2 O 3 ]–90 ZrO 2 ( x = 2, 3, 4, and 5 mol%) as well as 10–11 mol% Sc 2 O 3 –ZrO 2 electrolytes are presented. High dense homogeneous ceramic samples with fine microstructure were prepared from laser synthesized mixed nanopowders 10YSZ and 10ScSZ using low sintering temperatures of 1010–1300 °C. Stabilization of cubic fluorite-type phase has been achieved for Y-doped ScSZ composites at these temperatures. It is shown that the DC conductivity of the Y-doped ScSZs decreases proportionally to the yttria content throughout the temperature range studied, from 500 to 900 °C. Ageing behavior of the electrolytes was studied at 850 °C for 1200–2700 h. Low resistivity degradation of Y-doped ScSZ not exceeded 10% during extended annealing for 2700 h has been obtained for the samples sintered below 1100 °C. High and stable conductivity has been obtained for 10ScSZ and 11ScSZ. Any decrease in their conductivity during extended annealing was not detected.

In this work, we carry out spectroelectrochemical studies of films of interpolymer complexes of polyaniline (PANI) prepared via the chemical and electrochemical template polymerization of aniline in the presence of polyamide sulfonic acids with different structures. It is shown that their spectroelectrochemical behavior in the near infrared region depends on the rigidity of the chain of the polymer sulfonic acid matrix. Electrodeposited films of PANI complexes with a rigid-chain polyacid exhibit a more intense absorption in the near infrared region (1000–2200 nm) and a less intense absorption in the absorption region of localized polarons (around 750 nm) in comparison with complexes with a flexible-chain polyacid. The comparison of the dependence of absorption in the near infrared region on potential with the cyclic voltammetry curves suggests that the chromophores responsible for this absorption are radical cations in nature. In the spectra of the films of chemically synthesized PANI complexes with a flexible-chain polyacid, during a long-term cycling in the region of potentials of the first redox stage of PANI, the absorption in the near infrared region which corresponds to delocalized polarons is also formed. This is apparently attributed to the intensification of the intermolecular interactions under the conformational fluctuations that accompany the change in the degree of oxidation of the film during cyclic voltammetry.

The matrix polymerization of aniline in the presence of mixtures of rigid-chain and flexible-chain polymer sulfoacids was investigated in the work. The optical, electric, and spectroelectrochemical properties of the forming interpolymer complexes of polyaniline, as well as their morphology, were studied. The dominating influence of rigid-chain polyacid on the process of formation of the interpolymer complexes of polyaniline even in the case of application of the mixture with the prevailing content of the flexible-chain polyacid was detected. The nonadditive dependence character of the viscosity of the mixtures of polyacid solutions, the duration of the induction period of aniline polymerization, and the optical absorbance and conductivity of the obtained complexes of polyaniline relative to polyacid ratios in the mixture was shown. The presence of the intermolecular interaction in the mixtures of polymer sulfoacids was shown via viscometry method, which may be the reason for the nonadditivity of the observed phenomena.

Conducting polyaniline (PANI) was chemically synthesized in the presence of water-soluble aromatic polyamides containing sulfonic groups: poly-(p,p’-(2,2′-disulfonic acid)-diphenylene-tere-phthalamide) (t-PASA, rigid backbone), poly-(p,p’-(2,2′-disulfonic acid)-diphenylene-iso-phthalamide) (i-PASA, semi-rigid backbone) and their copolymer (co-PASA) with the monomers ratio 1:1, as well as in the presence of flexible-backbone polyacids: poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA) and poly(styrene sulfonic acid) (PSSA). In these conditions the matrix polymerization of aniline results in the formation of water-soluble interpolymer complexes of PANI with the above cited polyacids. The character of spectral changes in the UV, visible and near IR (UV–Vis–NIR) range during the synthesis and the polymerization rates depend strictly on the structure of polyacid matrix. Higher flexibility of the polyacid backbone (PAMPSA, PSSA) contributes to higher relative absorption of localized polarons (750 nm), while in the spectrum of interpolymer complexes with rigid-chain polyacid (t-PASA) the absorption of delocalized polarons (1300–1500 nm) prevails. The complexes with semi-flexible i-PASA and co-PASA exhibit intermediate behavior. The results are interpreted in terms of differences in the inter-chain interactions in the interpolymer complexes of different structure. Fourier transform infrared (FTIR) spectroscopy data support the assumption of the incorporation of the polyacids in the PANI through an interaction between sulfonic groups of the polyacids and nitrogen atoms of PANI. Spectroelectrochemical and electrochemical (cyclic voltammetry) studies of the films cast from the obtained solutions showed that the formation of quinoid units at high oxidation level is retarded in the interpolymer complexes of PANI with rigid- and semi-rigid-chain polyacids. Atomic force microscopy (AFM) and direct current (DC)-conductivity data are also presented.

A conducting organic polymer is visualized on a laser photoelectron projection microscope, which is based on Letokhov’s concept and has a nanometer spatial resolution. Photoelectron images of polyaniline (which is the most promising representative of conducting polymers) with a magnification of ∼105 have been obtained when a 100-nm quartz capillary coated with a film of this material was irradiated by femtosecond laser pulses. The projection photoelectron method using 400- and 800-nm laser radiation has made it possible to directly reveal the existence of the redox heterogeneity of the organic polymer, which is due to the contact of the sections of polyaniline with different oxidation degrees and strongly affects the electric conductivity of the sample.

Conductivity of yttria stabilized zirconia produced from weakly agglomerated nanopowder was investigated by ac impedance spectroscopy. Dense ceramic samples with the grain size from 90 to 800 nm were prepared at the variation of both pressing and sintering conditions. It was found that the bulk conductivity is not affected by grain size, while grain boundary conductivity is dependent on this factor. Observed grain boundary resistance increases with grain size. This relationship is contrary to the previous results obtained for the range from 1 to 18 microm where grain boundary resistance decreased with grain size. Maximum of grain boundary resistance versus ceramics grain size is observed at 450 degrees C for the grain size about 270 nm.

Chemical matrix polymerization of aniline was performed in the presence of polyacids with various macromolecule chain flexibility. Aniline polymerization in the presence of flexible chain polyacids leads to the formation of interpolymer complexes of polyaniline (PANI) of double-stranded structure with a high content of localized polarons and, in the presence of rigid chain polyacids, it leads to the formation of complexes with comblike structures with a high content of delocalized polarons. During the synthesis of PANI at a reduced temperature, the induction period increases and the films of the obtained complexes have high conductivity than in the case of synthesis at room temperature. Electrical and spectral properties and surface morphology of the PANI interpolymer complexes were investigated.

With the purpose of determining prospects of possible applications of interpolymer complexes of polyaniline (PANI) with poly(amidosulfonic acid)s, we have performed a comparative study of polyaniline films prepared by electrochemical polymerization of aniline in the presence of the polyacids distinguished by different rigidities of the polymer backbone: (1) poly(2-acrylamido-2-methyl-1-propanosulfonic acid) (flexible backbone); (2) poly-p,p′-(2,2′-disulfoacid)-diphenylen-iso-phthalamid (semi-rigid backbone); (3) poly-p,p′-(2,2′-disulfoacid)-diphelylen-tere-phthalamid (rigid backbone); and (4) a copolymer of the latter two acids with monomer feed ratio 1:1 (co-PASA). Spectroelectrochemical studies in the UV–vis–NIR range showed that PANI complexes with rigid-chain polyacids far more effectively modulate absorbance in the Vis–NIR range and can be considered as promising candidates for “smart windows” development. Due to the presence of bulky unmovable polyacid anion, PANI interpolymer complexes (particularly those with the semi-rigid-chain polyacids) possess much wider pH range of electroactivity than common PANI, which is of great importance for biosensor applications. The interpolymer complexes with flexible-chain and semi-rigid-chain polyacids exhibit good optical response to ammonia vapors at conditions of high humidity, which make them promising materials for the development of ammonia optical sensors.

Electrochemical matrix polymerization of nanostructured polyaniline layers in the presence of polyamidosulfonic acids differing in the rigidity of the polymer framework was studied in a wide concentration range. The spectroscopic, electrochemical, and morphological properties of the resulting layers were examined. It was found that the accelerated electropolymerization is due to (1) preliminary association of aniline with the sulfo groups of the polyacids and (2) a high local concentration of the protons near its macromolecule. The use of a polyacid with a rigid polymer framework afforded an interpolymer complex with polyaniline in side chains. With a semirigid matrix, both a two-strand complex (characteristic of an acid matrix with a flexible chain) and a branched complex were obtained.

It is found that one of the types of molecular organic nanocrystals, the so-called J-aggregates, is able to modify optoelectronic properties of electroactive polymers. It is intrinsic that the polyaniline interpolymeric complex, known as p-type semiconductor, turns into electroluminescent material in the presence of J-aggregates of 3,3-di(gamma-sulfopropyl)-5,5-dichlorotiamonomethincyanine triethylammonium salt. During the studying of new organic light-emitting diode structures, in which the polyaniline/J-aggregates polymeric composite forms both recombination and emitting layers, a polyaniline intrinsic electroluminescence spectrum is obtained. The electroluminescence band completely coincides with the polyaniline photoluminescence spectrum; it has maximum at 400 nm. The electroluminescence mechanism in the studied nanocomposites is discussed.

Nanoobjects of interpolymer complex of polyaniline (PAn) and polysulfonic acid have been synthesized. The matrix chemical synthesis of PAn was carried out in aqueous solution at room temperature in the presence of poly-(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA) as a matrix. The choice of PAMPSA was determined by its good solubility in water, perfect film-forming properties and high molecular weight (~ 2000000). The polymerization process of aniline on PAMPSA took place at pH ~ 2 on the polymer backbone at high rate, while aniline concentration was sufficiently low. The true solution of PAn-PAMPSA interpolymer complex was coated on mica substrates. We have studied PAn films surfaces using FEMTOSCAN atomic force microscope (AFM) in dependence on the solution concentrations and the presence of strong electrolyte (HCl).

By means of magnetic pulsed compaction and sintering of weakly aggregated alumina based nanopowders the jet forming nozzle samples for hydroabrasive cutting were fabricated. The ceramics were obtained from pure alumina, as well as from alumina, doped by TiO2, MgO and AlMg. The ceramic properties of the channel surface and the nozzle volume were investigated. It was shown that the samples sintered from AlMg doped Al2O3 powder had the best desired mechanical properties and structural characteristics: relative density ~0.97, channel microhardness – 18-20 GPa, channel surface roughness ~0.7 /m, average crystallite size ~1 /m.

The not-sufficient-enough conductance of semioxidized protonated polyaniline (PANI) is usually attributed to the presence of ordered quasi-metallic domains surrounded by a poorly conducting amorphous phase. The paper presents experimental results testifying to the existence, in semioxidized PANI, of multilevel redox heterogeneity that crucially effects the conductance magnitude in view of specific topology at which higher-oxidized (conducting) domains are surrounded by less oxidized (poorly conducting) domains and because the PANI conduction is extremely sensitive to the oxidation degree. It is shown experimentally that the interphase doping with metals and degenerate semiconductors of a semioxidized salt of PANI and poly(2-acrylamide-2-methyl-1-propanesulfonic acid) (PAMPSA) with a 1: 2 ratio between PANI and PAMPSA raises the PANI-PAMPSA conductivity by 3–8 orders of magnitude due to the formation near the interface of thin layers whose conductance depends on the work function of the material in contact with PANI-PAMPSA and in extreme cases substantially exceeds the conductance of gold and copper at room temperature.

Magnetic Pulse Compaction (MPC), as a dynamic compaction, can be possible to reach higher relative density of nano metallic compacts owing to sufficiently high pressure and adiabatic heating in very short duration of an order of µsec. The present work is concerned with the magnetic pulsed compaction of the nano-sized aluminum powders, which particle size was a range of 50 ~ 100 nm passivated in air. The compaction pressure was 1.5 GPa for 300 µsec in the temperature range from 20°C to 500°C. The grain size of compacts was maintained less than 50 nm, which was analyzed by X-ray diffraction (XRD) using Scherrer method. From the calculation of adiabatic heat and of pressure induced by thermal expansion, and the observation by transmission electron microscopy (TEM), it was found that Al2O3 could be broken and dispersed with a few nano-meter sizes in the Al matrix and that the ultra fine and uniform bulk structure was maintained up to 400°C of compaction temperature.e

The possibility of the desorption of complicated molecular complexes by soft X rays resulting from a solid target irradiated by a single sharply focused femtosecond laser pulse with an energy of several millijoules has been experimentally demonstrated for polyaniline, which is an organic conducting polymer. X-ray desorption and photodesorption of polyaniline by femtosecond laser pulses have been compared using a time-of-flight mass spectrometer. The results provide the possibility of studying surfaces with spatial nanoresolution and high elemental (chemical) selectivity, as well as observing the photodesorption with a high temporal resolution.

The derivative voltabsorptoammetry, XPS, AFM and optical microscopy reveal the redox heterogeneity in thin polyaniline (PAn) films. The autocatalytic character of the oxidation processes results in the formation of the heterogeneous structures in PAn at various scales from molecular to macroscopic.

The fractionating vacuum thermal deposition of emeraldine base produces the oligomers of polyaniline dispersed in the polymer organic matrix. The cyclic acid-base treatment of the low temperature fractions results in restoration of their polyaniline-like spectral, electrochemical, electric and paramagnetic properties. This is not the case for the high temperature fractions possibly as a consequence of their more defective structure and higher content of the thermal destruction products.

Polyaniline (PANI) was synthesized by chemical oxidation of aniline in the presence of mixtures of water-soluble poly(sulfonic acids) of different nature. Under these conditions, the use of polyacid templates leads to the formation of interpolymer complexes of PANI and polyacid mixtures. The obtained PANI complexes were characterized by UV, visible, near IR, and Fourier transform infrared spectroscopy. It was shown that the rigidity of the polyacid backbone and the composition of a polyacid mixture affect the electronic structure of PANI complexes and the duration of the induction period of aniline oxidation. Domination of the more rigid-backbone template in the synthesis of PANI complexes with mixtures of the rigid- and flexible-backbone polyacids was observed. According to the viscometry and FTIR spectroscopic data, the reason of the domination is the existence of the intermolecular interaction between the polyacids in the mixture. In this case, duration of the induction period of aniline oxidation was between these values for pure polyacids.

The evaporation duct strongly influence microwave radars and communication systems. For evaluation of their performance in such environment combination of split-step parabolic equation and Monin-Obukhov similarity theory are usual approach. There are several variants of semiempirical functions used in the similarity theory which leads to different models for evaporation duct height estimation. Five models were analyzed in this paper and evaporation duct height derived from them were compared with ”effective” duct height obtained minimizing the difference between measured propagation factor and split-step parabolic equation calculation for varying evaporation duct height by least-square method. The best result in average was showed by ECMWF model and for other models ”effective” evaporation duct heights was lower then obtained from bulk measurements. It means that combination of these models and split-step parabolic equation method leads to overestimation of propagation factor values.

A semiconductor photoelectrochemical photographic device (SPEPD) having as high as 107-108 cm2/] sensitivity was developed using vacuum evaporated thin films of CdSe on Sn02-glass substrates as photoelectrodes and polyacrylamide gel films containing electrochromic components as an image recording layer. Photographic characteristics of SPEPD were investigated under both cathodic and anodic polarization of the photoelectrode with different electrochromic and model recording layers. The effect of photoelectrochemical corrosion of the photoelectrode on such characteristics was estimated and a method of electrode protection was suggested.

The method of electrochemical extraction of oxygen from air employing a solid oxide electrolyte (SOE) is presented. The prototype of electrochemical oxygen generator (pump) for medical applications has been developed and fabricated. It is based on thin-walled tubular segments of YSZ electrolyte (170 μm) with LSM based electrodes (~20 μm). Different technologies: nanopowder production by laser ablation, casting of polymer-ceramic tapes, formation of electrodes-electrolyte green structures by radial magnetic pulsed compaction followed by cosintering at 1200°C, were used for segments fabrication. The magnetron sputtering method was applied to protect metallic interconnects (Crofer 22 APU) with (Mn-Co)3O4 layer. Presented oxygen generator prototype produced 9 liters of pure oxygen per hour under applied power of 50 W at 800°C. No noble metals were used in construction.

We combine in this work the measurement of local optical transmission in the near-field with the mapping of the third harmonic generation of semiconducting polymer samples. The use of a linear method with the scanning near-field optical microscope (SNOM) and a nonlinear method with the Third Harmonique Generation (THG) microscope reveal the variation and the nature of the nanomorphology of doped polyaniline thin films.

An influence of aggregation degree of alumina nanopowder and of radial magnetic pulsed compaction conditions on the powder densification and on the density distribution inside compacts has been investigated experimentally. The usage of radial magnetic pulsed compaction allows to compact alumina nanopowders up to high densities at low degree of aggregation. The compacts homogeneity is attained by appropriate compaction pulse duration and by the usage of powder packing prior to compaction until the condition with high local sound speed is achieved.

Fabrication of dense YSZ electrolytes and porous LSM cathodes in the shape of tubes using a radial magnetic pulsed compaction of multilayered tubular blanks of powder tapes has been investigated. The tapes were prepared with butyral resin binder. The multilayered blanks were compacted magnetically. Magnetic pressures of 0.2-0.3 GPa in amplitude, sintering temperatures as low as 1100-1300 °C (in air) with holding time of 20-540 min have been used. Cathode tubes of 0.2-1.0 mm thick exhibited the reproducible open porosity up to 45 %. YSZ electrolyte tubes with the wall of 100-450 microns thick had near full relative density, 0.97-0.99, and were characterized with grains of 200-500 nm in size on the average depending on the sintering temperature. The electrochemical cells built up of as-prepared tubular electrolytes and traditional research electrodes were tested under the air-hydrogen fuel cell conditions. The specific output power, 0.6 W cm-2, was realized at temperature of 885 °C.

The emeraldine base was deposited on SnO2 glass substrates in vacuum by thermal evaporation in the temperature range 275–325 °C. The as-deposited films differ dramatically from the native polyaniline and are formed by the reduction of oligoanilines with molecular weight about 1500. The cycling acid-base treatment of vacuum thermally deposited films gives rise to formation of polyaniline-like material. The property restoration of sublimed films is apparently determined by the restoration of 3D associates in the film body. Molecular structure defects in vacuum-deposited films are responsible for the lower rates of coloration/decoloration, the lower contribution to imine formation and irreversible injection of anodic charge under the first oxidation/reduction cycle. The lower imine concentration in sublimed polyaniline films results in more coloration/decoloration cycles.

Electronic properties of polyaniline films depend strictly on their heterostructure influenced on the electronic structure and transport phenomena in these ones. We have obtained the evidences of existence of heterogeneity in molecular scale for the chemically prepared polyaniline and in microscopic and macroscopic scales for the vacuum deposited polyaniline films. The character of heterogeneity depends strictly on the nature of oxidant, concentrations, temperature, mass transfer and so on. The heterogeneity of the vacuum deposited polyaniline films influenced on their electrical conductivity, magnetic properties and the formation of so-called trapped charge. In turn these factors affect strictly on the electro chromic properties of polyaniline films. The principal reason of the heterogeneous structure formation is the autocatalytic character of the oxidation in course of synthesis and following processes. Based on these data we formulate hypothesis on the multilevel heterogeneity in polyaniline and other conducting polymers.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Heterogeneity of polyaniline and other conductive polymers in intermediate oxidation states is fundamental problem of physics and chemistry of these ones. Usually only advanced methods may be used for immediate detection of the heterogeneity in the molecular scale range. For the first time we have observed the process of the heterogeneous net-like structure formation in macroscopic scale under the oxidation of the evaporated polyaniline films by aqueous HNO3. and other oxidative agents. Formation of heterogeneous structure is explained in terms of nonequilibrium thermodynamic and chemical kinetics.

The phase transformation and densification behavior under high power millimeter-wave (mm-wave) radiation of a 30 GHz gyrotron and during fast conventional sintering of nanocrystalline γ-A12O3 powder have been investigated and compared. The powder used for compacts was synthesized from aluminum metal by application of the exploding wire technique in an oxidizing atmosphere. The particle size distribution of this powder has a maximum at about 20 nm. Magnetic pulse technique was applied for the compression of samples up to 80% of the theoretical density (TD). Both mm-wave sintering and fast firing in a conventional electrical resistance furnace enable the densification and a complete phase transformation into α-A12O3 already at a temperature of approximately 1150 %C. The average grain size of the sintered ceramic is in the range of 50 to 100 nm. With mm-waves densification starts at about 50 °C lower temperatures compared to conventional techniques and higher final densities were obtained already at 150°C lower temperatures.

The decontamination of the solutions from micropatogens and drug delivery are the important problems of modern life. It was shown that carbon nanotubes, polyaniline and their composites can interact with antibiotics-polypeptides and some viruses (pandemic strain of influenza viruses A(H1N1)v circulated in Russia in 2009–2010. During a short time drug and viruses can be absorbed by polyaniline and removed from aqueous solutions at the normal conditions. Polyaniline composites can be useful for the preparation of drug delivery and virus control filters and also in biotechnology for the improvement the methods of antibiotics purification.

This paper proposes a new polarization-microscope method of directly identifying influenza viruses and detecting their antigenic properties, based on nematic liquid crystals.

Conductive polymers are used because of their conductivity, which is associated with the microstructure of the material, determined by its degree of oxidation. To study the conductivity inhomogeneity of polymers, it is proposed to use thin layers of nematic liquid crystals, which reveal the structural inhomogeneity of the surface of the material. © 2004 Optical Society of America

An all solid-state photoelectrochromic element (PECE) was developed on the basis of electrochromic layers of WO 3 and polyaniline with a layer of polymer electrolyte placed on a base of polyamidosulfoacid, in which a thin-film CdS x Se 1-x photoresistor was used as an electronic key. The dependence of the sensitometric characteristics of the PECE on the applied voltage was studied.