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Abstract A study of a series of single-atom-alloy catalysts Pd1Ag3/Al2O3, Pd1Ag3/CeO2–Al2O3, and Pd1Ag3/CeO2–ZrO2 in the selective hydrogenation of diphenylacetylene (DPA) showed a significant (five-fold) increase in activity for the PdAg3/CeO2–ZrO2 sample in comparison with that of Pd1Ag3/Al2O3. It was especially noted that the increase in activity was not accompanied by a decrease in the selectivity for the target product. This catalytic behavior can be explained by two factors: (1) a more than twofold increase in the dispersity of the PdAg3/CeO2–ZrO2 catalyst and (2) a change in the electronic state of the nanoparticles, as determined from the results of an IR-spectroscopic study of adsorbed CO. The retention of the high selectivity of the synthesized catalysts indicated the stability of the structure of Pd1 monoatomic sites in the catalysts prepared by deposition on Ce-containing supports, which was also confirmed by the IR spectroscopy of adsorbed CO. The experimental results indicate that Ce-containing supports are promising for the synthesis of catalysts for the selective hydrogenation of substituted alkynes.

The structure of a novel pentanuclear heterometallic complex [Pd3La2(OOCMe)12(MeCOOH)4] with an unusual ratio of metals 3Pd:2La is studied by XRD. The complex is prepared by the reaction of palladium acetate [Pd3(OOCMe)6] with lanthanum acetate [La(OOCMe)3·1.5H2O]. The molecule of the complex contains two heterometallic binuclear fragments [PdLa(OOCMe)5(MeCOOH)2] connected to the structure-forming fragment [Pd(OOCMe)2] via bridging acetate groups and hydrogen bonds of coordinated acetic acid.

The structure of a new mononuclear acetate complex of palladium(II) with the bidentate substituted N-donor 5-nitro-1,10-phenanthroline ligand, namely [Pd(nphen)(OOCMe)2∙MeOH] is studied by X-ray crystallography. This compound is found to crystallize as a crystal solvate with methanol, forming a hydrogen bond with a molecule of the complex. The analysis of the crystal packing reveals the presence of both π–π stacking interaction between the aromatic systems of coordinated 5-nitro-1,10-phenanthroline and short C-H···O contacts.

Heterogenized catalysts were prepared by the immobilization of the homogeneous catalytic systems containing the rhodium complexes, copper compounds, and perfluoroorganic acids onto porous carriers. The activity of the catalysts was studied in the processes of CO oxidation and co-oxidation of CO and propane. The state of the catalyst components was determined and the possibility of their interaction was evaluated by X-ray spectroscopy (XANES and EXAFS) and electrospray mass spectrometry (ESI-MS). The oxidation of CO on the RhCl3-CuCl2-C3F7COOH/γ-Al2O3 catalyst in a flow reactor at 70–80 °C and atmospheric pressure occurs in an oscillating mode. The co-oxidation of propane and CO at 80–95 °C and a pressure of 1.0–1.5 MPa is basically possible but occurs with a low yield of propane oxygenates.

The interaction between the components of a Ru–Rb/Sibunit catalyst for the decomposition of ammonia is studied via XAFS spectroscopy, X-ray diffraction with synchrotron radiation, and high-resolution transmission electron microscopy. The porous structure of the samples is examined at the stages of preparation. A set of measures reveals the presence of ruthenium in the catalyst (mainly in the metallic state) and the absence of joint phases of ruthenium and rubidium. It is found that rubidium is in an oxidized state in the catalyst in the form of compounds in direct contact with particles of active component and comparable in size to the latter, and as small clusters found mainly in the structure of carbon support.

The structure of Pd–Ag/Al2O3 samples with different Ag/Pd ratios has been studied by a complex of physicochemical methods (H2-TPR, XRD, H2-TPD, TEM). Catalysts have been synthesized by supporting an active component on α-Al2O3 and γ-Al2O3. X-ray diffraction analysis has revealed the formation of a Pd–Ag substitutional solid solution with a face-centered cubic crystal lattice owing to alloying of the Pd and Ag components. An increase in the Ag content in the composition of bimetallic nanoparticles hinders the formation of palladium hydride (PdHx), which is completely suppressed at a ratio of Ag/Pd > 0.5. Infrared spectroscopy of adsorbed CO has revealed the formation of single-atom Pd1 sites on the surface of supported Pd–Ag bimetallic nanoparticles isolated from each other by silver atoms. Analysis of the structural stability of isolated Pd1 sites has shown that, under conditions of CO adsorption at 150°C, the stability of the sites can be provided by an increase in the Ag/Pd ratio to ≥2.

Novel one-pot synthesis of trans-stilbene comprises hydrogenation of diphenylacetylene into cis-stilbene followed by its hydroisomerization, over the catalyst being intermetallic PdxIny/Al2O3 system with isolated single-atom Pd1 sites. The hydroisomerization rate in the process is comparable or exceeds the over-hydrogenation into 1,2-diphenylethane thus providing 76% yield of trans-stilbene in the case of Pd2In3/Al2O3 catalyst. This result presumably stems from the formation of ordered single-atom Pd1 sites with favorable hydroisomerization ability on the surface of PdxIny catalysts.

The results of studies on selective hydrogenation of acetylene to ethylene over bimetallic palladium-containing catalysts were summarized. Regular and specific features of the catalyst action in gas-phase hydrogenation of traces of acetylene in the acetylene-ethylene mixture produced by pyrolysis of petroleum feedstock, as well as in liquid-phase hydrogenation of mixtures enriched in acetylene and hydrogen were analyzed. The advantages of ethylene production by liquid-phase hydrogenation of acetylene were shown, and ways of increasing the selectivity to ethylene in this process were considered.

Post-synthesis treatment of bimetallic catalysts in different gas phases resulting in the adsorption-induced segregation is among promising approaches to enhance their activity not compromising selectivity towards a number of low-temperature reactions. Our recently published paper (M.A. Panafidin, A.V. Bukhtiyarov, I.P. Prosvirin, I.A. Chetyrin, A.Yu. Klyushin, A. Knop-Gericke, N.S. Smirnova, P.V. Markov, I.S. Mashkovsky, Y.V. Zubavichus, A.Yu. Stakheev, V.I. Bukhtiyarov, A mild post-synthesis oxidative treatment of Pd-In/HOPG bimetallic catalysts as a tool of their surface structure fine tuning. Appl. Surf. Sci.) reports on Pd-In intermetallic formation regularities and their evolution after storage in air as well as during treatment in oxygen at submillibar pressures. The current paper gives an extended representation of experimental ex situ/in situ synchrotron-based photoelectron spectroscopy (SRPES) and scanning tunnelling microscopy (STM) data used to derive scientific conclusions in the paper quoted above.

Local structure of Pd1 single sites on the surface of Pd1In1 intermetallic nanoparticles supported on α-Al2O3 was investigated by the combination of CO-DRIFTS spectroscopy and DFT. CO-DRIFTS spectra of PdIn/Al2O3 catalyst exhibit only one asymmetric absorption band of linearly adsorbed CO comprising two peaks at 2065 and 2055 cm−1 attributable to CO molecules coordinated to Pd1 sites located at (110) and (111) facets of PdIn nanoparticles. The absence of bridged or hollow-bonded CO bands indicates that multipoint adsorption on PdIn nanoparticles is significantly hindered or impossible. DFT results show that on (110) facet multipoint CO adsorption is hindered due to large distance between neighboring Pd atoms (3.35 Å). On (111) facet multipoint CO adsorption on surface palladium atoms is impossible, since adjacent Pd atoms are located below the surface plane.

A series of oxidative treatments of PdIn-supported intermetallic nanoparticles at different temperatures were performed. The bulk and surface structure of catalyst during phase transformation was investigated by bulk- and surface-sensitive techniques (in situ XAFS, DRIFTS of adsorbed CO). It was found that comparison of palladium and indium fractions in bulk and on the surface suggests the formation of a «core-shell» structure. According to obtained results, the core consists of In-depleted intermetallic compound or inhomogeneous bimetallic phase with the inner core of metallic Pd, when a mixture of indium oxide, metallic palladium and small part of PdIn is present on the surface.

The structure and catalytic characteristics of a bimetallic catalyst containing Pd1In1 nanoparticles deposited on the surface of γ-Al2O3 were studied. The formation of intermetallic nanoparticles was determined by X-ray diffraction analysis and confirmed by X-ray photoelectron spectroscopy and IR spectroscopy of adsorbed CO. In the hydrogenation of acetylene in excess ethylene, PdIn/Al2O3 had significantly higher selectivity of ethylene formation (~86%) than monometallic Pd/Al2O3 (~35%). The high selectivity of PdIn/Al2O3 is explained by two factors: (1) the formation of monatomic Pd1 sites isolated from one another by In atoms and (2) the change in the electronic state of Pd atoms in the intermetallic nanoparticles.

The structure and catalytic properties of a bimetallic Pd–Ag/α-Al2O3 catalyst are studied in the liquid-phase hydrogenation of substituted internal and terminal alkynes using diphenylacetylene, phenylacetylene, 1-phenyl-1-propyne, and 1-phenyl-1-butyne as sample alkynes. IR spectroscopy of adsorbed CO, X‑ray diffraction (XRD), and electron microscopy were used to show that the active sites on the Pd–Ag nanoparticle surface are Pd1 sites. The synthesized Pd–Ag/α-Al2O3 catalyst shows a much higher selectivity in the hydrogenation of internal symmetric and asymmetric alkynes compared to the monometallic Pd/α‑Al2O3 sample. Also, it was found in the hydrogenation of diphenylacetylene and 1-phenyl-1-propyne on Pd–Ag/α-Al2O3 that the rate of the stage of desired olefin hydrogenation substantially decreases, which favors the kinetic control of the process.

In the present research, the process of the formation of the active components of Pd-Zn catalysts supported on carbonaceous material Sibunit prepared by the joint impregnation (Pd:Zn = 1) is studied. It was shown by means of TPR and EXAFS techniques that the interaction between palladium and zinc begins already at T > 200 °C. During the reduction in hydrogen at temperatures of 200–300 °C the surface of particles being formed is enriched with oxidized zinc. In the temperature range of 400–500 °C zinc is completely reduced, and the crystal lattice of a substitutional solid solution based on fcc lattice of palladium is restructured in tetragonal lattice of PdZn. However, an increase of the calcination temperature in H2 atmosphere (500 °C) significantly rises up the probability of partial destruction of bimetallic phase due to the partial migration of zinc atoms from the surface into the bulk of particles.

Based on the Sibunit carbon composite, Ru–Cs(Ba)/Sibunit catalysts with Cs(Ba) : Ru molar ratios of 0.5, 1.5, and 2.5 were obtained. The catalytic activity of the obtained promoted catalysts in the decomposition of ammonia and their thermal resistance to methanation are compared. In the reaction of ammonia decomposition, the specific activity (Wsp) of barium-containing catalysts proved to be 2 times lower than the specific activity of cesium-containing samples with the same molar M : Ru ratio. Thus, Wsp at 500°С was 29.4 mmol H2 min–1 for 0.5Cs–Ru/Sibunit and 15.4 mmol H2 g–1cat min–1 for 0.5Ba–Ru/Sibunit. It was shown that the introduction of barium at molar ratios Ba : Ru = of 0.5–2.5 significantly increases the thermal stability of the samples defined as the ratio of the weight of hydrogen obtained on the catalyst to the weight of carbon subjected to methanation. There is 52 g H2 for nonpromoted Ru/Sibunit catalyst, 370 g H2 for the 0.5Ba–Ru/Sibunit sample, 200 g H2 for the 1.5Ba–Ru/Sibunit sample, and 150 g H2 for the 2.5Ba–Ru/Sibunit sample per 1 g of carbon loss.

The reaction of platinum acetate blue, empirically described as Pt(OOCMe)2.50, with palladium(II) acetate Pd3(μ-OOCMe)6 gave the first heterometallic acetate-bridged platinum(II) and palladium(II) complex Pd2Pt(μ-OOCMe)6 (I) as co-crystallizates 17Pd2Pt(μ-OOCMe)6 ⋅ 4Pd3(μ-OOCMe)6 ⋅ 42C6H6 (IIa) and 17Pd2Pt(μ-OOCMe)6 ⋅ 4 Pd3(μ-OOCMe)6 (IIb). Single crystal X-ray diffraction (CIF files CCDC nos. 1568105 and 1852744), EXAFS, and quantum chemical studies (DFT and QTAIM) of complex I revealed a slightly distorted triangular structure similar to the structure of palladium(II) acetate Pd3(μ-OOCMe)6 and hypothetical platinum(II) complex Pt3(μ-OOCMe)6. The thermal decomposition of complex IIa gives the bimetallic alloy PtPd2. A combined X-ray diffraction and EXAFS study demonstrated that the obtained material consists of core (Pt)–shell (Pd) particles with an average size of ~28 nm and a minor amount of smaller (~5 nm) PdO nanoparticles on the surface. The obtained results are useful for the understanding of the nature and structure of the supported phase of heterogeneous Pt–Pd catalysts.

Three-component Ru-Ba-Cs/C catalysts supported on the graphite-like carbonaceous composite material Sibunit were synthesized. The effects of the graphitization procedure of the support (thermal treatment at 1900 °C) on the phase composition and the distribution of the components were studied. The catalytic activity in the ammonia decomposition reaction and the thermal stability of the samples were examined in comparison with the untreated support. The samples were characterized by Raman spectroscopy, XAFS, TEM, and XRD methods. It was found that in the case of untreated support, Ru presents in the form of both the metallic and partially oxidized fine particles. The graphitization of the carbon support facilitates the formation of large, well-crystallized metal particles. Barium in both samples was found to be unevenly distributed and presented mainly as large particles of carbonate. Cesium-containing species were not detected. The effect of the support graphitization on the thermal stability is comparable with catalyst modification by Ba and Cs. At the same time, combination of these effects noticeably increases the efficiency of the catalyst. Thus, the non-promoted Ru catalyst deposited on the untreated support decomposes 107 g of NH3 per 1 g of the lost carbon. Modification of the catalyst with Ba and Cs allows one to increase this value up to 498 g of NH3, while graphitization of the support and application of the combined approach were shown to give 910 and 1577 g, correspondingly.

В представленном обзоре обобщены результаты исследований, посвященных селективному гидрированию ацетилена в этилен на биметаллических палладиевых катализаторах. Проанализированы общие закономерности и особенности их действия в газофазном гидрировании следов ацетилена в ацетилен-этиленовой смеси, получаемой пиролизом нефтяного сырья, а также в процессе жидкофазного гидрирования смесей, обогащенных ацетиленом и водородом. Показаны преимущества получения этилена путем гидрирования ацетилена в жидкой фазе и рассмотрены способы повышения селективности этого процесса.

We report the accomplishment of the first stage of the development of a novel manually curated database on glycosyltransferase (GT) activities, CSDB_GT. CSDB_GT (http://csdb.glycoscience.ru/gt.html) has been supplemented with GT activities from Saccharomyces cerevisiae. Now it provides the close-to-complete coverage on experimentally confirmed GTs from the three most studied model organisms from the three kingdoms: plantae (Arabidopsis thaliana, ca. 930 activities), bacteria (Escherichia coli, ca. 820 activities) and fungi (S. cerevisiae, ca. 270 activities).

Intermetallic Pd-In particles formation and their deliberate post-synthesis modification by oxidative treatments under carefully controlled conditions have been investigated by the combination of synchrotron radiation-based photoelectron spectroscopy and scanning tunneling microscopy. It is demonstrated that a prolonged contact of Pd-In/HOPG samples with air led to a partial decomposition of intermetallic particles giving rise to the formation of Pd0 species homogeneously distributed over bulk, surface indium hydroxide and subsurface indium oxide. A mild oxidative treatment (0.25 mbar O2, 150 °C) leads to the indium surface segregation and formation of indium oxide homogeneously distributed over the depth and metallic Pd predominantly localized in the interior. The indium oxide component becomes surface localized upon further temperature increase to 200 °C.

The effect of palladium segregation was studied which resulted from the effect of CO and O2 on the surface structure and catalytic characteristics of the Pd–Ag2/Al2O3 catalyst. The IR-spectroscopic study of adsorbed CO showed that Pd1 centers isolated from each other by silver atoms predominated on the surface of reduced Pd–Ag2/Al2O3, as evidenced by the almost complete absence of absorption bands typical for the multicentred CO adsorption. In the course of catalyst treatment with CO and O2, the intensity of absorption bands characteristic of the multicenter CO adsorption considerably increased due to the transformation of a portion of monatomic Pd1 centers into multiatomic Pdn ones as a result of the surface segregation of Pd. In this case, a substantial increase in the catalyst activity in the liquid-phase hydrogenation of diphenylacetylene was observed. It was established that, after treatment with CO, the catalyst selectivity for the formation of a target olefin (stilbene) remained almost constant, whereas the treatment with O2 led to a decrease in the selectivity because of more considerable surface modification.

A method for fractionation of the starting carbon composite Sibunit by density was used to obtain three samples of Sibunit with different values of the specific surface area: Sib10 at 439 m2/g, Sib13 at 389 m2/g, and Sib17 at 256 m2/g. Investigation of Sibunits using both methods, that is, X-ray diffraction analysis and combination (Raman) scattering spectroscopy, did not reveal significant differences (the parameters of the crystal lattice and the ID/IG ratio). The fractionated supports were used to obtain Ru-containing catalysts for ammonia decomposition reaction (0.1 MPa, 400°C). The dependence of the specific catalytic activity calculated per 1 m2 of the support specific surface a for catalysts of the same composition (4.0% Ru and 13.6% Cs) has an extreme form. The authors connect this with two factors: the blocking support pores contain an active component and a change in features of ruthenium interactions with the promoter (Cs) of the catalyst.

A treatment of PdAg3/Al2O3 catalyst with CO at 250 °C enhanced its activity towards the selective C2H2 hydrogenation without any noticeable losses of C2H4 selectivity. The CO-DRIFTS and XPS data acquired in situ have indicated that the observed effect arises from Pd surface segregation induced by the CO adsorption and partial transformation of isolated surface Pd1 active sites into Pd2 dimers. The catalytic performance of PdAg3/Al2O3 was found to be similar or even better as compared to the best reported catalysts.

Effect of the phase composition of aluminum oxide [γ- and (δ + θ) phase] and introduction of zinc additives on the catalytic properties of 0.5% Pd/Al2O3 systems in the reaction of liquid-phase hydrogenation of acetylene into ethylene under an elevated pressure in a flow-through mode was studied. An increase in the activity of the Pd catalyst upon modification with zinc is only observed in the case of a system supported by the mixed phase of (δ + θ) aluminum oxide. XAFS spectroscopy was used to find that the increase in the activity and selectivity with respect to ethylene (in the presence of carbon monoxide) on the (0.5% Pd–0.62% Zn)/(δ + θ)-Al2O3 catalyst is correlated with the formation of the PdZn intermetallic compound.

Palladium catalysts on various types of supports were studied in the liquid-phase hydrogenation of diphenylacetylene. Samples of Pd/SiO2–Al2O3, Pd/MgAl2O4, Pd/Al2O3, and Pd/TiO2 were characterized by the chemisorption of the CO and IR spectroscopy of adsorbed CO. The use of n-hexane as the solvent increases the reaction rate, which can be explained by the better solubility of hydrogen in the liquid phase. It is established that the acid–base properties of the support do not affect the activity and selectivity of the catalysts in the reaction under study. However, they alter the electronic state of palladium. According to the catalytic tests, Pd/TiO2 has the highest activity (turnover frequency) and selectivity to alkene. The comparison of the obtained catalytic data and the results of IR spectroscopy made it possible to conclude that this is due to the electron density redistribution between the palladium and TiO x particles, which is caused by the strong metal–support interaction.

Pd–Ag nanoparticles with different Pd/Ag ratio were deposited onto fiber glass by using the technique of surface self-propagating thermal synthesis (SSTS) and characterized by X-ray photoelectron spectroscopy (XPS), atomic absorption spectroscopy (ААS), and EXAFS spectroscopy. The samples reduced in hydrogen exhibited the formation of Pd–Ag alloy whose tentative structure and composition were suggested. Thermally scheduled reduction of Pd–Ag catalysts in hydrogen made the Ag atoms partially oxidized. Reported are the catalytic properties of synthesized Pd–Ag samples in selective hydrogenation of acetylene.

The textural and structural properties of mixed oxides Ga2O3–Al2O3, obtained via impregnating γ-Al2O3 with a solution of Ga(NO3)3 and subsequent heat treatment, are studied. According to the results from X-ray powder diffraction, gallium ions are incorporated into the structure of aluminum oxide to form a solid solution of spinel-type γ-Ga2O3–Al2O3 up to a Ga2O3 content of 50 wt % of the total weight of the sample, accompanied by a reduction in the specific surface area, volume, and average pore diameter. It is concluded that when the Ga2O3 content exceeds 50 wt %, the β-Ga2O3 phase is observed along with γ-Ga2O3–Al2O3 solid solution. 71Ga and 27Al NMR spectroscopy shows that gallium replaces aluminum atoms from the tetrahedral position to the octahedral coordination in the structure of γ-Ga2O3–Al2O3.

Ru–Ba–Cs/Sibunit ternary catalysts were synthesized. Their activity in ammonia synthesis and the thermal stability of the support in a reducing atmosphere at elevated temperature depend on the molar ratio of the promoters. The results of studies using physical methods suggest that cesium predominantly interacts with the support, acting as an electronic promoter, whereas barium is a structural promoter. The synergistic action of the promoters at increased barium content of the catalyst was revealed. The highest activity in ammonia synthesis, 34.5 mLNH3 gcat–1 h–1, was reached for the 4% Ru–10.8% Ba–2.6% Cs/Sibunit catalyst.

The effect of composition of the chlorine-containing precursors of ruthenium and heat treatment conditions on the preparation of catalysts supported on carbon composite Sibunit for the ammonia synthesis was studied. The activity of Ru-Ba/Sibunit samples was shown to depend on ruthenium dispersion and residual chlorine content in the catalyst. The removal of outer-sphere chloride ions from ammonia complexes of ruthenium via ionic exchange and the replacement of hydrogen reduction of the Ru precursor by calcination in an inert atmosphere prevent sintering and agglomeration of the active component particles, thus enhancing the catalyst activity.

Pd/Sibunit and Pd–M/Sibunit (M = Ga, Zn, or Ag) catalysts have been synthesized, and their catalytic properties in liquid-phase acetylene hydrogenation have been investigated. Doping of the palladium catalyst with a metal M leads to the formation of the Pd2Ga, PdZn, or Pd0.46Ag0.54 bimetallic compound. The bimetallic particles are much smaller (1.6–2.0 nm) than the monometallic palladium particles (4.0 nm). Doping with zinc raises the ethylene selectivity by 25% without affecting the activity of the catalyst. Specific features of the effect of each of the dopants on palladium are reported.

The in situ DRIFT-CO and XPS data demonstrated that the mild oxidation of PdIn intermetallic nanoparticles results in the partial oxidation of an In component and the trans-formation of isolated Pd1 sites to Pdn multiatomic ones thus enhancing PdIn activity in the liquid-phase hydrogenation of diphenylacetylene without sacrificing the alkene selectivity.

Culture of mouse macrophages (RAW 264.7 ATCC strain) in wells of a 6-well plate was infected with M. tuberculosis in proportion of 15 mycobacteria per one macrophage and then treated with a lytic strain of mycobacteriophage D29. Antibacterial efficacy of mycobacteriophages was studied using D29 phage (activity 108 plaque-forming units/ml) previously purified by ion exchange chromatography. After single and double 24-h treatment, the lysed cultures of macrophages were inoculated onto Middlebrook 7H10 agar medium. The number of mycobacterial colonies in control and test wells (at least 3 wells in each group) was 300.178±12.500 and 36.0±5.4, respectively (p

Ruthenium catalysts supported on graphite-like carbon material Sibunit modified with rubidium was investigated for the reaction of decomposition of ammonia. Thermal stability of carbon support for synthesized samples of 4% Ru/Sibunit and 8.5% Rb-4% Ru/Sibunit was also studied. It was found that the presence of rubidium reduces the rate of catalyzed particles deposited ruthenium negative reaction of gasification of Sibunit 3 times, in terms of the decomposition reaction of ammonia, and 1.5 times reduced and the activity of the catalyst in the target reaction.

The supercompression of matter caused by gravitational coupling or self-gravitational forces leads to density growth by several orders in magnitude. Keeping in mind the importance of self-gravitation in astrophysical processes like supernovae star evolution we consider it reasonable to develop a numerical technique based on the consistent approximation to the terms describing gravitational energy transfer into the kinetic energy of a matter in the star along its life cycle. The so-called completely conservative gas-dynamics difference schemes including the gravitation effects are the proper numerical technique able to simulate correctly the problems concerning gravitational coupling effects. The accounting for gravitational forces in the construction of completely conservative difference schemes is a significant complication. In the paper, we propose an integrally-consistent difference scheme that utilizes the method of support difference operators thus providing a possibility to conform the balance between kinetic and gravitational energy increments or losses. According to this method, we use the result of the total gravitational energy varying and construct the symmetrized strain rate tensor as the base operator. The result of varying the gravitational energy of the system is a discrete convolution of the Newton gravitational tensor in the difference media under study, which exhaustively answers all the gravitational processes unfolding against the background of the hydrodynamic motion of matter. The symmetrized strain tensor governs the kinematic motion in a considered system. The conjugate operator related to the convolution of these tensors automatically gives the approximation to the gravitational forces acting in the interior of the balance volume of the difference model built via the support operator approach.

Phase transformations of a newly synthesized heterobimetallic ZnPt(OOCMe)4(H2O)(MeCOOH)2 acetate in a chemically reductive atmosphere at mildly elevated temperatures are thoroughly studied in order to optimize conditions for the formation of nanostructured PtZn intermetallic compound. According to XAFS and XRD data, the first stage of reductive thermolysis is the reduction of the noble metal, while zinc remains in an oxygen environment. At the second stage the reduction of Zn and the formation of the bimetallic solid solution with the fcc lattice occur. It is shown that recrystallization of solid solution to ordered PtZn intermetallic compound with the tetragonal structure occurs in a narrow temperature range of 250–275 °C. Based on these results, the optimum reduction temperature for the preparation of supported bimetallic Pt–Zn/Al2O3 catalyst was determined to be 300 °C. Results of catalytic tests of the supported material are reported.

Catalytic performance of Pd1Ag3/Al2O3 single-atom alloy (SAA) catalyst was studied in liquid-phase hydrogenation of diphenylacetylene (DPA) and compared with the performance of the reference monometallic Pd/Al2O3. Formation of SAA structure in Pd1Ag3/Al2O3 was confirmed by FTIR CO technique. It was found that Pd1Ag3/Al2O3 single-atom alloy catalyst exhibits excellent selectivity in diphenylethene (stilbene) (ca. 98 %), which remains constant over a wide range of DPA conversions (0–95%), while over Pd/Al2O3 selectivity decreases steadily with the increase in DPA conversion. It is remarkable that the selectivity of Pd1Ag3/Al2O3 depends neither on hydrogen pressure (5–15 bar), nor on DPA concentration (0.0262 – 0.159 mol/l). In contrast, over the reference Pd/Al2O3 selectivity tends to decrease with increasing P(H2) and decreasing DPA concentration. The proposed reaction network comprises hydrogenation of DPA in a parallel formation of cis and trans-stilbene with following hydrogenation to bibenzyl and direct formation of the latter from the initial DPA. The calculations clearly shows the capability of the kinetic model to describe the experimental dependencies for Pd1Ag3 single-atom catalyst in an excellent way with the degree of explanation equal to ca. 99 %.

The structure of Ga2O3–Al2O3 supports and Pd/Ga2O3–Al2O3 catalysts and the performance of these catalysts in liquid-phase acetylene hydrogenation have been investigated. The deposition of Ga(NO3)3 onto Al2O3 by impregnation followed by calcination of the impregnated support at 600°C yields γ-Ga2O3–Al2O3 solid solutions containing up to 50 wt % Ga2O3. X-ray diffraction characterization of model palladium catalysts and their temperature-programmed reduction with hydrogen have demonstrated that, while palladium in Pd/Ga2O3 is in the form of a Pd2Ga alloy, in the Pd/γ-Ga2O3–Al2O3 catalyst there is no direct interaction between PdО and Ga2O3 particles and palladium is in the monometallic state. The introduction of 10–20 wt % gallium oxide into Al2O3 lowers the activity of the supported palladium catalyst relative to that of the initial Pd/Al2O3 but increases the ethylene yield by enhancing the ethylene formation selectivity.

The CO-DRIFTS investigation of a Pd–In catalyst obtained via the PdIn(AcO)5 complex showed the presence of single palladium atoms isolated by indium on the surface. A short-time exposure to air under ambient conditions induced the decomposition of the single-atom structure, which can be recovered by mild reduction.

Bimetallic Pd-In/HOPG model catalysts have been prepared and investigated using scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) techniques. The spontaneous formation of intermetallic Pd-In nanoparticles or at least partial In diffusion into Pd particles with emergence of In-Pd surface alloy already at the step of In deposition onto monometallic Pd/HOPG sample has been revealed. An additional cycle of oxidation-reduction treatment is necessary in order to form the uniform Pd-In alloy species. For a series of Pd-In/HOPG model catalysts, we demonstrate that the reversible RedOx transformation Pd-Inintermet ↔ Pd° + InOx can be efficiently used to deliberately tune the nanoparticles surface composition/structure and respective catalytic characteristics.

The reaction of Pd3(OOCMe)6 with indium(III) and gallium(III) acetates was studied to prepare new PdII-based heterometallic carboxylate complexes with group 13 metals. The heterometallic palladium(II)–indium(III) acetate-bridged complexes Pd(OOCMe)4In(OOCMe) (1) and Pd(OOCMe)4In(OOCMe)·MeCOOH (1a) were synthesized and structurally characterized with X-ray crystallography and extended X-ray absorption fine structure in the solid state and solution. A similar Pd–Ga heterometallic complex formed by the reaction of Pd3(OOCMe)6 with gallium(III) acetate in a dilute acetic acid solution, as evidenced by atmospheric pressure chemical ionization mass and UV–vis spectrometry, was unstable at higher concentrations and in the solid state. Complex 1 catalyzes the liquid-phase-selective phenylacetylene and styrene hydrogenation (1 atm of H2 at 20 °C) in acetic acid, ethyl acetate, and N,N-dimethylformamide solutions, while no Pd metal was formed until alkyne and alkene hydrogenation ceased.

The structural characteristics and catalytic properties of Pd/Sibunit and Pd-Ga/Sibunit catalysts for the liquid-phase hydrogenation of acetylene prepared via impregnation of joint alcoholic precursor solutions are studied. A surface film of gallium oxide covering the surfaces of bimetallic particles forms on a sample modified with gallium, leading to partial blocking of its active centers. This explains the lower activity and selectivity to ethylene of Pd-Ga/Sibunit catalyst, relative to Pd/Sibunit.

A series of catalysts Pd/Sibunit and Pd–Ga/Sibunit were prepared by impregnation with joint solutions of palladium and gallium nitrates in ethanol. The state of the active component and catalytic properties of the samples were studied in the liquid-phase hydrogenation of acetylene. The EXAFS method showed that the active component in the gallium-modified catalysts exists in the form of a non-stoichiometric Pd–Ga solid solution. The activity of the catalysts was found to be determined by the ratio Pd:Ga. It was shown that at the molar ratios Ga:Pd > 0.5:1, the catalytic activity is reduced by blocking the surface of the bimetallic particles by gallium oxide.

The Pd/Sibunit and Pd-Ga/Sibunit catalysts, which were supported on Sibunit with different textural characteristics, for liquid-phase acetylene hydrogenation were investigated. It was shown that the use of the support with a large surface area leads to an increase in catalytic activity and selectivity due to the increased dispersion of the active component. The promoting effect of gallium correlates with the probability of contact between the supported Pd and Ga components.

In conditions of prevalence of medicine-resistant strains of mycobacteria of tuberculosis necessity in accelerated, including phenotype techniques of detection of sensitivity of mycobacteria to anti-microbial chemotherapeutic medications in clinical samples is an actual issue. The results of application of accelerated phenotype techniques of detection of sensitivity of clinical strains of mycobacteria of tuberculosis to anti-microbial chemotherapeutic medications on the basis application of lytic mycobacteriophage D29 are presented. The principle of technique is in evaluation of reproduction of mycobacteriophage in cells of mycobacteria of tuberculosis in presence of sensitive to them anti-bacterial medications. The reproduction of mycobacteriophage is evaluated by quantitative analysis of phage DNA in polymerase chain reaction in real-time. The study used 102 clinical strains of mycobacteria of tuberculosis obtained after primary cultivation or re-cultivation in tubes of MGIT system (Bactec). After positive results of growth of mycobacteria of tuberculosis were obtained, the samples were incubated during 48 hours in CO2 incubator in the presence of critical concentrations of 10 widely applied in case of treatment tuberculosis medicinal substances in liquid nutrient medium Middlebrook 7H9 enriched with components OADC, in format of 24 well cultural plate with volume of nutrient medium 1 ml per well. Whereupon, in plate wells deposited 2x103 plaque-forming units of mycobacteriophage D29. After 24 hours a qualitative detection of phage DNA was implemented with polymerase chain reaction in real-time using reagents phage D29 ("Syntol", Russia). The increasing of threshold level of fluorescence of Ct more than to 2 cycles in samples with antibiotic as compared with control testifies sensitivity of the analyzed strain of mycobacteria of tuberculosis to antibiotic. The level of coincidence made up to 91% in comparative study with inoculation in Lowenstein-Jensen nutrient medium. The level of coincidence made up to 96% in comparative study with Bactec test-system of limited number of strains with establishment of sensitivity for 10 medications. The data was confirmed concerning inverse relationship of value ∆Ct and minimal inhibiting concentration of medication. The supposed high efficiency of possible reagents' set on the basis of presented technique on cost/quality criterion.

The potential of surface self-propagating high-temperature synthesis (SSHS) for obtaining (CuO-CeO2)/glass cloth catalysts is demonstrated. The dependence of the structural and catalytic properties of the catalysts on their preparation conditions (nature of the fuel component) is considered. X-ray diffraction, electron microscopy, and EXAFS data suggest that the short-term action of high temperature in the SSHS leads to the complete decomposition of the precursors and has an effect on the distribution of the resulting phases. According to H2 TPR and XPS data, the degree of dispersion of CuO and the electronic state of the reacting CuO and CeO2 phases depend on the choice of fuel. This is likely due to fuels varying in the amount of heat released in their combustion. The degree of dispersion of CuO and the total contribution from Cu1+ and Ce4+ to the electronic state of the active component increase as the standard enthalpy of combustion increases in the urea < glycerol < citric acid order. This leads to an increase in the catalytic activity of the (CuO-CeO2)/glass cloth system in selective CO oxidation.

Model catalysts Pd/Ga2O3 of selective liquid-phase hydrogenation of acetylene to ethylene were prepared by impregnation of β-Ga2O3 with a palladium nitrate solution with following drying and reduction in a hydrogen flow at 200 °C. A part of the samples was then calcined in an argon flow at 200–500 °C. The as-prepared samples were tested in the reaction of selective liquid-phase hydrogenation of acetylene. EXAFS was used to study structure of the catalyst components. Based on the EXAFS data it was found that Pd–Ga alloys present in the subsurface region of Pd particles. The presence of these alloys increases activity and selectivity of catalysts. The alloys are decomposed by calcination in inert atmosphere following decrease in catalytic activity.

The technique of Surface Self-propagating Thermal Synthesis (SSTS) was used to prepare Pd/γ-Al2O3/fiber glass (FG) catalysts for selective liquid-phase hydrogenation of acetylene in the presence of CO. The results of XRD SR analysis (in synchrotron radiation) in combination with the technique of arrested combustion shed new light on the dynamic of phase transformations in the systems under study and variation in the size of diffraction-active crystallites. The catalytic performance of synthesized catalysts was found to be close to that of similar conventionally prepared catalysts. The EXAFS and TEM data afforded to estimate the variation in relative amounts of Pd0 and PdO in synthesized catalysts. In the course of selective hydrogenation, PdO rapidly (

Size characteristics of oocytes of the elder generation of the end of previtollogenesis, as well as of the beginning and middle of the phase of cytoplasm vacuolization in two forms of Baikal grayling Thymallus baicalensis were studied. In each form, the dependence of oocyte parameter on the age and size of females is traced. During the studied phases of development—at the termination of the period of previtellogenesis and at the proper beginning of the period of vitellogenesis—oocytes of the white and black graylings have similar sizes; cytoplasm vacuolization in white grayling proceeds less actively. It was established that differences in the diameter of mature ovicells in the black and white Baikal graylings result from dissimilar rate of accumulation of trophic substances in the oocytes of the given forms of this species and are determined by differences in the rate of growth of oocytes during the formation in them of yolk inclusions.