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The electronic structures and the character of the electron density redistribution in the palladium complexes with the redox-active ligands in the oxidized and nonoxidized forms are studied by X-ray photoelectron spectroscopy. According to the photoelectron spectroscopic data, the redox-active ligands exist in different oxidation states due to the redox process proceeding “at ligand.” It is shown that the transition from the neutral to oxidized semiquinone form (from [Pd(LMe)2]·2Cl·H2O to [Pd $$\left( {{\text{L}}_{{{\text{Ph}}}}^{{{\text{ISQ}}}}} \right)$$ 2]) occurs in the ligand and involves no palladium ions, and the oxidation state of palladium remains unchanged: Pd(II). A significant difference in the photoelectron spectroscopic characteristics obtained for the oxidized trans-complex at 298 and 153 K indicates a specific electronic lability of this complex.

New applications, in particular in medicine, require the creation of track-etched membranes (TMs) with fundamentally new properties. There are well-known TMs made from polycarbonate, polyimide, polypropylene, polyethylene terephthalate, polyethylene naphthalate, and polyvinylidene fluoride; that is, polymers characterized by high chemical resistance. This study focuses on the development of a membrane made of the biodegradable polymer polylactic acid (PLA). Films prepared from a 1% solution of polylactic acid with a molecular weight of Mw = 121000 g/mol were taken as the initial matrix for TM fabrication. The films were irradiated with 1.2-MeV Xe ions at a fluence of 3.1 × 107 cm−2 on an IC-100 cyclotron. Etching was carried out in NaOH solutions of various concentrations (0.1, 1, or 2 mol/L) with varying the temperature from 18 to 70°С and the treatment time from 5 to 30 min. It has been revealed that the optimal treatment conditions for irradiated PLA films are etching in 1 M NaOH at a temperature of 44°C. This mode, with a time variation from 10 to 30 min, makes it possible to obtain through pores with a diameter of 0.6 to 1.5 µm with channel geometry close to cylindrical. It has been found that an increase in the etching time over 20 min leads to a decrease in the roughness of both membrane sides.

The effect of bulky tridentate ligands on the geometry of carboxylate complexes was studied in relation to hexahydro-1,3,5-trimethyl-1,3,5-triazine (TACH). The reaction of [Co2Gd(NO3)(Piv)6(MeCN)2] (Piv is the pivalic acid anion) with TACH gave the complex [Co2Gd(NO3)(Piv)6(TACH)2] (I), in which the initial heterometallic moiety was retained and cobalt(II) ions coordinated the N-donor ligand to give a half-sandwich structure. The use of Cd(II) and Eu(III) pentafluorobenzoates in the reaction with TACH resulted in the isolation of only the homometallic complex [Cd(Pfb)2(TACH)2] (II) (Pfb is pentafluorobenzoic acid anion). Owing to high coordination number of cadmium(II) ion in II, a sandwich complex with two TACH molecules coordinated to the same metal ion was obtained. The structure of new complexes was determined by X-ray diffraction (CIF file CCDC nos. 2062230 (I) and 2062229 (II)). It was shown that binding of an N-donor ligand to a metal ion induces a significant distortion of the metal coordination polyhedra and a conformational change of hexahydro-1,3,5-trimethyl-1,3,5-triazine.

Effects of the low-temperature plasma exposure, γ-irradiation, and joint g-irradiation and plasma exposure on the structure and surface properties of thin films based on polylactic acid (PLA) have been investigated. Films were obtained by the method a solvent-casting. It has been shown that films based on polylactic acid have topographically different sides: a smoother inner side and embossed outer one. PLA films have properties close to those hydrophobic, with a contact angle in the range of 70°-73° regardless of the surface side and belong to a weakly polar materials. The combined effect of plasma and gamma radiation slightly changes the surface topography. The effect of low-temperature plasma on the surface of the films leads to a decrease in the contact angle by 13°-55° (9-11%) and an increase in surface energy due to the polar component. The results of in vivo experiments on rabbits are presented. Biomicroscopy, optical coherence tomography, morphological and electron microscopic examination of the cornea after implantation of initial and radiation and plasma treated films showed that implantation of the films in the anterior chamber is not accompanied by a pronounced inflammatory reaction and increased intraocular pressure, while maintaining the morphological structure of the cornea almost unchanged.

Films of TiO2 nanorods prepared under different conditions of hydrothermal synthesis were studied. With an increase in the hydrothermal synthesis temperature at a synthesis time of 24 h, the length of the TiO2 nanorods formed first increases and then decreases, and the nanorod diameter changes. The TiO2 film consisting of nanorods 4100 nm long and 100 nm in diameter, prepared at 180°C, exhibits the highest photocatalytic activity. This effect is predominantly associated with high specific surface area of the samples.

In this work, predictions of the curing time at a given temperature to a given degree of curing for four thermosetting materials have been made based on the data of differential scanning calorimetry (DSC) and they have been verified. An assessment of the possibility of using various methods for predicting the parameters of the reaction of thermosetting plastics has been given.

The reactions of cadmium(II) and europium(III) pentafluorobenzoates ([Cd(Pfbz) $$\left( {{{{\text{H}}}_{{\text{2}}}}{\text{O}}} \right)_{{\text{4}}}^{ + }$$ }n ∙ n(Pfbz)–] (I) and [Eu2(Pfbz)6(H2O)8] ∙ 2H2O (II), respectively; Pfbz is pentafluorobenzoic acid anion) with the N-donor ligands (pyridine (Py), 2-phenylpyridine (Phpy), and 3-ethynylpyridine (Etypy)) afford a series of new Cd–Ln complexes with Pfbz– anions and Py or its substituted analogues: [Cd2Eu2(Pfbz)10(Py)4] (III), [Cd2Eu2(Pfbz)10(Phpy)2(MeCN)2] · 5MeCN (IV), and [CdEu2(Pfbz)8(Etypy)(H2O)2]n ∙ 3nMeCN ∙ n(Etypy) (VI). Similar reactions of compounds I and II with 2,4-lutidine (Lut), isoquinoline (Iquin), 2,2'-biquinoline (Biquin), and 7,8-benzoquinoline (Bquin) give the following cadmium complexes as the major products of crystallization from the reaction solutions: [Cd(Pfbz)2(Lut)]n (V), [Cd(H2O)(Pfbz)2(Iquin)2]n (VII), [Cd(Рfbz)2(Biquin)] (VIII), and $$[{\text{Cd}}{{({\text{Pfbz}})}_{{\text{3}}}}]_{n}^{-}$$ ∙ n(HBquin)+ (IX), respectively. The X-ray diffraction data (CIF files CCDC nos. 1987805 (I), 1987808 (III), 1987829 (IV), 1987817 (V), 1987822 (VI), 1987823 (VII), 1987824 (VIII), and 1987826 (IX)) are examples of the formation of new unusual coordination polymers.

Copper(II) ferrite is synthesized by the co-precipitation method in the absence and in the presence of polyvinyl alcohol which is followed by thermally treatment at 300, 500, 700, and 900°С. The specific surface area of thus prepared samples is determined. X-ray diffraction data point to the partial thermal reduction of CuFe2O4 + polymer samples. CuFe2O4 samples synthesized in the absence of polymer are reduced in the electrochemical system to form Fe–Cu composites with the different content of reduced metals depend on the temperature of thermal treatment. Electronic spectroscopy studies of samples reduced electrochemically reveal the presence of crystallites shaped as hexagonal prisms presumably formed by copper and iron-copper layers and covered by reduced iron and its oxide Fe3O4. The experiments show that the thus synthesized Fe–Cu composites exhibit electrocatalytic activity in electrochemical hydrogenation of acetophenone: its hydrogenation rate is higher by a factor of 2.5–6.4 as compared with its electrochemical reduction.

The effect of intermediate ion cleaning of the Ti target on the structure and properties of the polymer fiber scaffold made by electrospinning from poly-L-lactic acid (PLLA) was investigated during deposition of Ti-N-containing coatings by DC reactive magnetron sputtering of the Ti target in a nitrogen atmosphere. SEM investigation shows that the selected plasma treatment modes can modify fiber PLLA scaffolds without changing their morphological properties. Energy-dispersive spectroscopy showed that the Ti concentration on the surface of PLLA scaffolds is increased under intermediate ion cleaning of the target, although ion cleaning did not affect the Ti distribution across the scaffold cross section. Using optical goniometry, it was found that scaffold surface treatment allows changing the contact properties of the surface from hydrophobic to hydrophilic.

This paper presents data on the effects of steam sterilization on the properties of thin films based on polylactic acid. It has been established that thin films based on polylactic acid and poured from solutions of 10, 20, and 30 g have two topographically different sides. One side (internal) has a more prominent surface. The other side (external) has a smooth surface. It is reflected in the roughness parameters. Ra of the internal side varies from 0.01 to 0.018 μm. Ra of the external side is 0.17–0.4 μm. The average roughness increases from 0.17 to 0.4 μm with an increase in the mass of the solution poured into films. Sterilization contributes to a change in the surface of the polylactic acid films and makes their profile more prominent. This leads to a significant increase in the roughness of both sides by more than 5 times. In addition, it was found that thin polylactic acid films have hydrophobic (θ = 80°) properties. Steam sterilization reduces the wetting angle by 14°–15° (17–18%) and increases the surface energy values to a greater extent owing to the polar component. These changes increase the hydrophilicity of the studied material.

Formation of normal tissue structure, homeostasis maintenance, and tissue damage repair require proliferation and differentiation of stem cells. A distinctive feature of these cells is a unique organization of metabolic pathways, in which contribution of energy production mechanisms to the general cellular metabolism is principally different from that in differentiated cells. Moreover, metabolic changes during differentiation of embryonic and postnatal stem cells have several specific features. The alterations in the stem cell metabolism are not simply consequences of cell differentiation, but also active regulators of this process. Metabolic enzymes and intermediates control and guide the maintenance of stemness, self-renewal, and differentiation of stem cells. The review discusses the patterns and molecular mechanisms of the switch in the metabolism of stem cells during their transition from the pluripotent to differentiated state with the special emphasis on how metabolic processes occurring in the stem cells regulate their functions, ability to differentiate, and the choice of the direction for development.

An experimental setup is created to study the dynamic behavior of the side ledge under the electrolysis in a cryolite-alumina electrolyte. The installation has a built-in window on the side panel, which allows the lining material and, hence, the heat flow to be varied. The dynamic formation of a side ledge is experimentally studied as a function of temperature, the electrolyte velocity, and the heat flow during the electrolysis of aluminum. The rate of the ledge formation and the ledge thickness are determined by the heat flow caused by the electrolyte temperature, the cell side temperature, and the liquidus temperature. As in an industrial electrolysis cell, the side ledge profile formed in the experimental cell can be conventionally divided into the following three zones: the ledge at the bottom in contact with liquid aluminum, the ledge at metal/electrolyte interface, and the ledge at the electrolyte level. If the temperature of the inner wall is higher than the liquidus temperature, the side ledge does not form; if it is lower, the side ledge forms until these temperatures become the same. Therefore, the stability of the side ledge depends on the heat flow from the center to the walls; however, the dynamic behavior (solidification/melting) of the ledge in the metal zone occurs slowly and differs from the behavior of the side ledge.

The influence of pulsed gamma-neutron irradiation on the surface morphology of GeSi/Si(001) heterostructures with surface self-assembled GeSi nanoislands grown by the combined sublimation molecular-beam epitaxy of Si and the low-pressure vapor-phase epitaxy of Ge is experimentally studied. Gamma-neutron irradiation is found to cause a change in the shapes of self-assembled GeSi nanoislands, in particular, a reduction in the aspect ratio of the nanoislands. The effect is related to elastic-strain relaxation in the GeSi nanoislands under their exposure to elastic waves generated in the course of gamma-neutron irradiation.

Nickel oxide nanosheets were manufactured using sol–gel technology and hydrothermal treatment. The effect of hydrothermal treatment on the hierarchical organization character of the thus-manufactured oxide powder was shown. The microstructural parameters of the powder were studied by transmission (TEM) and scanning (SEM) electron microscopy; The homogeneity of the powder and the absence of impurities of another chemical composition were verified by energy dispersive elemental microanalysis (EDX).

The reactions of the complex [Co(DAP)2(Piv)2] · Piv (Ia), where Piv is the pivalate anion, DAP is 1,3-diaminopropane, with Cd(II) and Li(I) pivalates afford heterometallic compounds, molecular complex [CdCo(DAP)2(Piv)5] (I) and polymeric complex [LiCo(DAP)2(Piv)4]n (II) (CIF files CCDC nos. 1908223 and 1908224, respectively). According to X-ray photoelectron spectroscopy, the electronic structure of cobalt ions in complexes Ia and I corresponds to low-spin Co(III) surrounded by strong-field ligands. The thermal destruction of I and II, studied by synchronous thermal analysis, includes stages of desorption of solvate molecules, destruction of the 1,3-diaminopropane molecule with nitrogen evolution, and degradation of carboxylate anions. The final product of thermolysis of I is the complex oxide CdCoO2.

The electronic structure of mono- and binuclear platinum complexes with N-phenyl-o benzosemiquinondiimine ligands was studied using X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and the density functional theory. The oxidation state of the central platinum ion corresponds to that of Pt(II). Upon the transition from the trans-complex 1 to the cis-complex 2 and to the binuclear complex 3, the electron density on platinum and nitrogen atoms decreases thus testifying the participation of platinum and nitrogen atoms in the oxidation processes and in the formation of binuclear complex 3.

The methods for restoration of the orientation distribution function (ODF) from experimental pole figures have been compared for materials possessing a low symmetry of specimen (by example of the median section of the hot-pressed band from Mg–4.5% Nd magnesium alloy), namely, the method of texture components using radial normal distributions on SO(3) with different spreading and the method of superposition of a large number of normal distributions with equivalent small spreading. Both approaches have demonstrated similar ODFs. In this case, the former method, which is less sensitive to measurement errors of pole figures, is based on nonlinear optimization with a complex choice of initial approximations of the parameters of the model. The latter approach is more sensitive and easier to use.

Polymer-silver composites are prepared by in situ introducing silver(I) nitrate to the oxidative polymerization of aniline and polycondensation of aniline or melamine with formaldehyde. The data of the X-ray phase analysis and electron microscopy are used to study structure-phase changes and morphological features of the structure of composites after synthesis and in electrochemical systems, after their saturation with hydrogen and in the course of o-nitroaniline electrohydrogenation. It is shown that silver micro- and nanoparticles are formed as a result of chemical and/or electrochemical reduction of silver cations. A different electrocatalytic activity of the synthesized silver-containing composites as related to the structure of their polymer matrix is established.

Curing reactions of epoxy-imide binder and two prepregs based on it were studied by the method of differential scanning calorimetry (DSC). The effective activation energies were found, and predictions of storage time and curing time at given temperatures to different degrees of curing were made. The influence of fillers on prepreg curing kinetics was found.

Mixed aniline–melamine–formaldehyde polymer was synthesized by parallel polycondensation of the monomers with formaldehyde. Copper(II) chloride and copper oxides (CuO, Cu2O) were introduced in situ the process. X-ray diffraction analysis revealed the presence of crystalline CuO phases at introducing CuCl2 into the polymer and the appearance of copper particles in all the synthesized composites after using them as catalysts in electrohydrogenation of o-nitroaniline, which is caused by electrochemical reduction of copper cations from copper oxides. The use of the synthesized composites for the cathode activation in electrohydrogenation of o-nitroaniline increases the process rate by a factor of 1.5–2.5 compared to electrochemical reduction, and with 100% conversion to o-phenylenediamine.

Concentration dependences of the density of aqueous solutions of bisadducts of light fullerene С60 and essential amino acids are studied by pycnometry. Concentration dependences of the average molar volumes and partial volumes of components (Н2О and corresponding bisadducts) are calculated for С60(C6H13N2O2)2–Н2О, С60(C4H8NO3)2–Н2О, and С60(C5H9NO2)2–Н2О binary systems at 25°C. Concentration dependences of the indices of refraction of С60(C6H13N2O2)2–Н2О, С60(C4H8NO3)2–Н2О, and С60(C5H9NO2)2–Н2О binary systems are determined at 25°C. The concentration dependences of specific refraction and molar refraction of bisadducts and aqueous solutions of them are calculated.

Understanding the mechanisms of cadmium and selenium behavior under near-surface conditions is very important for solving certain environmental problems. The principal aim of this study is physicochemical analysis of the formation conditions of synthetic cadmium selenite CdSeO3 · H2O and experimental investigation of its thermal stability and dehydration and dissociation mechanisms. The synthesis was performed by boiling-dry aqueous solutions of cadmium nitrate and sodium selenite. The obtained samples were identified with electron microprobe and powder X-ray diffraction. Complex thermal analysis (thermogravimetry and differential scanning calorimetry) have shown that CdSeO3 · H2O is dehydrated at 177–241°C in two stages, apparently corresponding to the formation of CdSeO3 · 2/3H2O. The Eh–pH diagrams were calculated using the Geochemist’s Workbench (GWB 9.0) software package. The Eh–pH diagrams have been calculated for the Cd–Se–Н2О and Cd–Se–CO2–H2O systems for the average content of these elements in underground waters. The formation of cadmium selenite, CdSeO3 · H2O in the oxidation medium is quite possible. The existence of CdSeO3 is possible at high temperature.

A novel derivatization method for the analysis of primary amines by MALDI mass spectrometry is proposed. Tris(2,6-dimethoxyphenyl) methyl carbenium cation reacts smoothly with primary amines, forming permanently charged adducts with the mass increment +359 Da and absorbance in the UV region. The approach was tested on a number of amines, including biologically active compounds and therapeutic agents.

Serum samples (33 healthy women, 34 ovarian cancer, 28 colorectal cancer, 34 syphilis patients and 136 patients with various benign gynecological diseases) were analyzed by MALDI-TOF MS peptide profiling and respective predictive models were generated by genetic and supervised neural network algorithms. Classification models for pathology versus healthy control showed up to 100% sensitivity and specificity for all target diseases. However, the specificity dropped to unsatisfactory 25–40% in case of target versus nontarget disease diagnostics. Expansion of the control group to an artificial “nominal control” group by adding profiles of benign gynecological diseases considerably improved specificity of the models distinguishing ovarian cancer from healthy control and benign gynecological diseases. The suggested version of MALDI-TOF MS profiling of sera could be applied to differentiate between cancers and benign neoplasms of the same localization which is a challenging task for classical methods. To increase the specificity of diagnostic methods based on peptidome analysis of blood samples, it is necessary to identify sets of concrete peptide structures which qualitatively or quantitatively differ among patients with different diseases.

Bimetallic Co–Cu polyaniline composites were produced by oxidative polymerization of aniline, with ammonium peroxydisulfate and hydrogen peroxide as oxidizing agents. Co(II) and Cu(II) chlorides were introduced into the polymer by the in situ method. It was found that the phase constitution of the composites is affected by their synthesis conditions and content of both metals in them. The electrocatalytic activity of the composites in the electrohydrogenation of p-nitroaniline in an aqueous-alcoholic-alkaline medium of the catholyte was studied and found to exceed that of composites synthesized with the use of H2O2 and evaporation of the solvent.

The results of investigation into the structure and in-vitro dissolution of titanium-oxynitride coatings deposited via reactive magnetron sputtering are presented. Data on the electrostatic and ζ surface potentials enable estimation of their contribution to adsorption processes and coating dissolution in vitro. Sample cultivation in a solution simulating the composition of the inorganic part of human blood plasma leads to surface mineralization, reduces the value and sign of the surface potential, and alters the surface wettability. The coating prevents the transition of iron ions into a solution and does not induce the calcification of an artificial surface.

The aim of this study is the synthesis of CuSeO3·2H2O (chalcomenite analog), ZnSeO3·2H2O, and ZnSeO3·H2O and the investigation of their solubility in water. CuSeO3·2H2O has been synthesized from solutions of Cu nitrate and Na selenite, while Zn selenites were synthesized from solutions of Zn nitrate and Na selenite. The samples obtained have been examined with X-ray diffraction and infrared and Raman spectroscopy. The solubility has been determined using the isothermal saturation method in ampoules at 25°C. The solubility has been calculated using the Geochemist’s Workbench (GMB 9.0) software package. Solubility products have been calculated for CuSeO3·2H2O (10–10.63), ZnSeO3·2H2O (10–8.35), and ZnSeO3·H2O (10–7.96). The database used comprises thermodynamic characteristics of 46 elements, 47 base particles, 48 redox pairs, 551 particles in solution, and 624 solid phases. The Eh–pH diagrams of the Zn–Se–H2O and Cu–Se–H2O systems were plotted for the average contents of these elements in underground water in oxidation zones of sulfide deposits.

A complicated, almost conflicting situation exists in contemporary biology, i.e., there are two scientific concepts in existence that solve some phylogenetic problems in a different way. These concepts are evolutionary morphology and molecular biology. Modern biology urgently needs these contradictions to be examined and removed.

The fabrication of photodetectors for the wavelength range of communications λ = 1.3–1.55 µm on the basis of Ge/Si(001) heterostructures with thick (~0.5 µm) Ge layers grown by the hot-wire technique at reduced growth temperatures (350°C) is reported. The single-crystal Ga layers are distinguished by a low density of threading dislocations (~105 cm–2). The photodetectors exhibit a rather high quantum efficiency (~0.05 at λ = 1.5 µm and 300 K) at moderate reverse saturation current densities (~10–2 A cm–2). Thus, it is shown that the hot-wire technique offers promise for the formation of integrated photodetectors for the wavelength range of communications, especially in the case of limitations on the conditions of heat treatments.

Science has accumulated to date such amounts of valuable and diverse information that no scientists can be encyclopedists (like those of the 17th and 18th centuries). Now every scientist is usually well informed only in one particular area and often needs consultations of other specialists. The current situation in biology is similar. In addition to evolutionary morphology, which represents fundamentals of zoology, there is a new, clearly cutting-edge and progressive area of studies, molecular genetics, which has already revealed many important general biological patterns. But the conclusions that follow from examining natural phenomena from this new point of view using new methods sometimes prove to be at odds with conventional notions. Considerable controversies have emerged on the phylogenetic position of the type Arthropoda. The peculiar features of the general body plan and the type of development of these animals seem to give evidence that they evolved from Annelida, with which they are often combined under the name Articulata. But attempts have been made to replace this concept by the idea that the clade Ecdysozoa, which includes Arthropods as well as such animals with low levels of organization as Nematoda and Priapulida, emerged early in the evolution of Bilateria. The main reason for combining the said animals in this clade is the fact that they have molts regulated with ecdysone; this point of view is supported by molecular genetic arguments. Although in this review this controversial problem is considered from the morphological point of view, the main purpose of the review is to emphasize the need to establish mutual understanding between morphologists and molecular biologists and carefully find out the causes of the existing disagreements. Rather than ideological opponents, the two areas of science should be allies helping each other to solve complicated problems.

The present paper discusses the evolutionary relationships between the blastopore and openings of the digestive tract in Bilateria, which have often been though to have great phylogenetic significance. In the case of multipolar immigration as the original type of gastrulation, the blastopore is absent, although the mouth is formed. The blastopore appeared simultaneously with gastrulation by invagination and became a pecursor of the mouth opening. Initially (in Acoelomorpha), the gastric cavity had only one opening (the mouth), which was located at the posterior end of the body. Subsequently, various ontogenetic changes resulted in a forward shift of the mouth. Concurrently, the anal opening emerged at the posterior end of the body from a new invagination of the ectoderm (proctodeum), which was not related to the blastopore. The same result is sometimes achieved by amphistomy, viz., the separation of the blastopore into two holes. In some animals, the connection between the mouth opening and the blastopore began to weaken and a stomodeum began to form at the anterior end of the body; deuterostomy thus emerged. A secondary mouth is inherent not only in Deuterostomia, but also in Priapulida, Nematomorpha, some Nemertea, Crustacea, and other animal taxa; therefore, it is of little phylogenetic significance. In all likelihood, deuterostomy is only the most efficient way of forming a through digestive tract during ontogeny. The hypotheses by Mamkaev [13], Martindale and Hejnol [26], and Martin-Duran et al. [25] are analyzed. It is proposed to divide Bilateria into three major groups: Acoelomata, Trochozoa, and Enterocoelia.

We investigate the photosensitivity spectra of photodiodes based on Si p-i-n structures with single-layered and multilayer self-assembled GeSi/Si(001) nanoisland arrays in the i region, which are grown using a technique combining Si molecular-beam epitaxy and Ge vapor-phase epitaxy, in dependence on the temperature, diode bias, and GeSi nanoisland parameters. We show that the temperature and field dependences of the diode photosensitivity in the spectral range of the interband optical absorption in GeSi nanoislands are determined by the ratio between the rate of emission of photoexcited holes from the nanoislands and the rate of the recombination of excess carriers in them. We demonstrate the possibility of determination of the hole recombination lifetime in GeSi nanoislands from the temperature and field dependences of the photosensitivity.

Copper-containing composites of polyaniline were synthesized by introducing copper(II) chloride (with the reduction of copper cations with sodium borohydride and hydrazine hydrate and without it) in the oxidative polymerization of aniline (ammonium peroxydisulfate oxidant). The resulting polyaniline-copper composites were studied by IR spectroscopy, atomic force microscopy, and X-ray diffraction analysis. The more drastic increase in the rate of hydrogenation of p-nitroaniline and its conversion (compared with those of the electrochemical process on the Cu cathode) resulted from the activation of the cathode with polyaniline composites with the copper salt, whose cations were reduced to the metal phases in the electrochemical system.

Heterometallic compounds of general formula [Fe 2 III MIIO(O2CR)6(H2O)3] · 3H2O (R = CH3, M = Co, Ni; R = CCl3, M = Co, Ni) have been studied by XPS. The compounds have been identified as high-spin complexes with metal atoms in oxidation states M(II) and M(III). Analysis of the XPS data revealed the tendency of the XPS pattern and magnetic parameters of molecules to change with a change in the electronic nature of metal atoms. The assignment is based on the degree of covalence of the M-O bond. In chloro-substituted heterocomplexes, electron density delocalization on the metal atoms with metal-to-ligand charge transfer through three bonds (M-O-C-C) is observed. The substitution in terminal groups leads to the change in the electron density distribution between the carboxylate and terminal groups.

The problem of the origin of the phylum Arthropoda was long considered solved based on evolutionary morphology data. But molecular biological studies of recent years have put forward a new solution that contradicts the old one. Hence, the need arises to review the argumentation of both sides and search for ways to reach a consensus. These two subjects constitute the scope of this paper.

Heterometallic complexes Fe2MO(Piv)6(HPiv)3 (M = Ni, Co) have been studied by XPS. The complexes are identified as high-spin complexes with metal atoms in oxidation states M(II) and M(III). A change in the ligand environment of metal atoms has an effect on both the energetic state of metal atoms and the XPS pattern. The substitution of a Co atom for the nickel atom in the heterometallic complexes changes the XPS pattern of iron and their magnetic state. For the Fe2MO(Piv)6(HPiv)3 complexes, quantum-chemical calculations have been performed at the density functional theory (DFT) level. In combination with XPS and magnetochemistry data, the quantum-chemical calculation demonstrates that the Fe, Ni, and Co atoms in the trinuclear complexes are in the high-spin local state and that the ground state is dominated by antiferromagnetic exchange interaction.

The interaction between the Earth’s ionosphere and magnetosphere in a situation when artificial disturbances are generated in the F region of the auroral ionosphere with the EISCAT/Heating facility is studied. An experiment was performed in the daytime when the facility effective radiated power changed in a stepwise manner. Wavelike disturbances with periods of (130–140) s corresponding to Pc4 pulsations were simultaneously registered by the method of bi-static backscatter and with ground magnetometers. The variations in the Doppler frequency shift were correlated with the changes in the facility power. Incoherent scatter radar measurements at a frequency of 930 MHz (Tromso) and numerical calculations were used in an analysis. It has been indicated that the ionospheric drift of small-scale artificial ionospheric irregularities was modulated by magnetospheric Alfven waves. The possible effect of powerful HF radioemission on the Alfven wave amplitude owing to the modification of the magnetospheric resonator ionospheric edge reflectivity and the generation of an outgoing Alfven wave above the region where the ionospheric conductivity is locally intensified has been considered.

Binuclear pivalate complexes of 3d transition metals (manganese, iron, cobalt, and nickel) with the same ligand environment and a lantern structure have been studied by X-ray photoelectron spectroscopy. The M2p, M3s, C1s, O1s, and N1s X-ray photoelectron spectra have been examined. A redistribution of electron density in the OCO group has been revealed. It has been shown that the theory fits the experimental data on the energy separation between the high- and low-spin components in the M3s spectra and between the spin doublet components in the M2p spectra. It has been demonstrated that the iron, cobalt, and nickel complexes are paramagnetic at room temperature, whereas the manganese complex exhibits antiferromagnetic properties. There is a correlation between the size of the 3d subshell of the transition metal atom and the M-O and M-N bond lengths.

This paper describes the growth of tubular polycrystalline 3C-SiC samples by chemical vapor deposition (CVD). The use of propionitrile as a precursor for nitrogen doping ensures the growth of polycrystalline 3C-SiC layers with a 1000°C resistivity of 0.1–0.2 Ω cm and zero temperature coefficient of resistance. Such 3C-SiC tubes can be used as silicon carbide electric heaters.

The results of studies on the catalytic hydrogenation of picolinic acid on a cathode activated with skeleton catalysts (Ni, Co) was considered. The main hydrogenation product—2-piperidinecarboxylic acid—is shown to be formed with high ∼95.0–98.0% yields in weakly alkaline catholyte solutions at 40.0°C.

Electrocatalytic hydrogenation of quinoline, quinoline N-oxide, 8-oxyquinoline, and 5,7-dibromo-8-oxyquinoline is studied in an aqueous alkali catholyte solution with the additive of organic solvents on skeleton catalysts (Ni, Co, Cu, Fe) used for cathode activation. It is shown that the main product of hydrogenation of quinoline and quinoline N-oxide is 1,2,3,4-tetrahydroquinoline, whereas that of hydrogenation of 8-oxyquinoline, and its dibromo derivative, is 1,2,3,4-tetrahydro-8-oxyquinoline. A conclusion is made on the basis of chromatographic analysis as to the consecutive-parallel processes of deoxidation and hydrogenation of the N-heterocycle under electrocatalytic reduction of quinoline N-oxide.

We have studied the effect of silicon-enriched vapor phase composition, deposition temperature, and CH3SiCl3 precursor concentration on the microstructure, resistivity, and compressive strength of 3C-SiC layers and optimized the conditions for the growth of polycrystalline 3C-SiC layers possessing high resistivity and compressive strength.

The electronic structure of mono-, hexa-, and nonanuclear cobalt trimethylacetate complexes was studied by XPS. The Co3s- and Co3p X-ray photoelectron spectra of the complexes were recorded. The Co3p spectrum of bivalent cobalt was calculated in the isolated-ion intermediate-coupling approximation. Spectrum analysis showed that the [Co(N-Phobsqdi)2(η′-N-Ph-opda)(OOCCMe3)] complex is a strong-field complex with Co(III) in the diamagnetic state; the [Co(dipy)2(OOCCMe3)2], [Co(dipyam)(OOCCMe3)2], and [Co9(μ3-OH)6(μ-OOCCMe3)12(OCMe2)4] are high-spin weak-field Co(II) complexes; and the [Co6(μ4-O)2(OOCCMe3)10(THF)4] complex contains both the Co(II) and Co(III) atoms. The energy position of major Co3s- and Co3p spectral maxima were found to be sensitive to the nature of the nearest environment of cobalt atoms. The data correlate well with X-ray crystallographic data.

The electronic structure and magnetic states in the heterometallic hexanuclear complex Mn 4 II Fe 2 III (μ4-O)2(Piv)10 · MeCN4 have been studied by X-ray photoelectron spectroscopy (XPS). The substitution of two Mn atoms for two Fe atoms in the hexanuclear complex was found to have an effect on the patterns of iron and manganese X-ray photoelectron spectra. XPS data are evidence of the high-spin paramagnetic state of MnII and FeIII atoms, as well as of the ligand-metal charge transfer upon complex formation. In the heteroatomic complex, the degree of bond covalence increased for both the manganese and iron atoms. The results obtained are in good agreement with X-ray diffraction data.

In experiments with rapeseed (Brassica napus L., cv. Westar) plants, it was confirmed that copper was considerably more toxic than zinc. The toxic effects of 50 and 150 μM CuSO4 were comparable to those of 1000 and 2500 μM ZnSO4. The analysis of the effects of these concentrations of copper and zinc on photosynthetic pigment contents and on the rate of lipid peroxidation did not reveal any reasons for different toxicities of these heavy metals (HM). Among biological effects studied, significant differences were found in the organ distribution of these metals in plants grown on both the standard medium and the medium with high concentrations of copper or zinc. Copper retained in the roots in relatively small amounts and was poorly transported over the aboveground part of the plants. It stayed mainly in the lower leaves, and its distribution changed only a little during the recovery of plants following the HM treatment. In contrast, zinc proved to be highly mobile, it was concentrated in the upper leaves and actively transported when the plants were transferred to a medium with the optimal HM concentrations. High copper concentrations slowed strongly zinc uptake by the roots but practically did not change its movement over the plant. In contrast, high zinc concentrations facilitated copper uptake by the roots but reduced its transfer to the aboveground organs. The data presented here allow us to hypothesize that biological peculiarities of organ and cellular distribution of copper and zinc in plants and interaction of these HM play an important role in the toxic effects of high concentrations of these HM and the mechanisms of adaptation to them at industrial environmental pollution used by rapeseed plants.

Equal-channel angular pressing (ECAP) of am MA2-1 alloy according to routes A and Bc is used to study the possibility of increasing the low-temperature deformability of the alloy due to grain refinement and a change in its texture. To separate the grain refinement effect from the effect of texture on the deformability of the alloy, samples after ECAP are subjected to recrystallization annealing that provides grain growth to the grain size characteristic of the initial state (IS) of the alloy. Upon ECAP, the average grain size is found to decrease to 2–2.4 μm and the initial sharp axial texture changes substantially (it decomposes into several scattered orientations). The type of orientations and the degree of their scattering depend on the type of ECAP routes. The detected change in the texture is accompanied by an increase in the deformability parameters (normal plastic anisotropy coefficient R, strain-hardening exponent n, relative uniform elongation δu) determined upon tensile tests at 20°C for the states of the alloy formed in the IS-4A-4Bc and IS-4Ao-4BcO sequences. The experimental values of R agree with the values calculated in terms of the Taylor model of plastic deformation in the Bishop-Hill approximation using quantitative texture data in the form of orientation distribution function coefficients with allowance for the activation of prismatic slip, especially for ECAP routes 4Bc and 4BcO. When the simulation results, the Hall-Petch relation, and the generalized Schmid factors are taken into account, a correlation is detected between the deformability parameter, the Hall-Petch coefficient, and the ratio of the critical shear stresses on prismatic and basal planes.

Specific features of the electronic structure and spin magnetic state of iron atoms in bi-, tri-, and hexanuclear iron trimethylacetate complexes were studied by X-ray photoelectron spectroscopy. A correlation was found between the ionicity (of the spin state of iron atoms) and Fe3s binding energies, exchange splitting of the final photoionization state, and the energy position and intensity of charge-transfer satellites. Nonequivalent iron states were identified in tri- and hexanuclear complexes. The overall magnetic moment of the complexes was found to decrease with an increase of the individual magnetic moments of iron atoms, which is evidence of complicated mutual orientation of atomic magnetic moments in the complexes.