4,110 research outputs found
Peculiarities of syntropic functional disorders of the digestive system against the ground of connective tissue dysplasia
A considerable occurrence of functional gastrointestinal disorders (FGID) in childhood, their frequent combination between themselves, the risk of transformation into organic pathology together with high collagen content in the digestive organs require investigation of pathophysiological relations of the pathology with collagen dysfunction. Objective of the study is to investigate the role of collagen disorders in FGID pathophysiology and assess their effect on clinical development of irritable bowel syndrome. 63 children suffering from FGID have been examined. Irritable bowel syndrome was diagnosed as a leading functional disorder of all the children examined. Syntropic functional biliary disorders were found in (38,46±6,13) % patients. By the results of molecular-genetic examination genetic polymorphism of COL3A1 rs1800255 with prevailing the genotype G/А – 47,62 % (95 % CІ 35,04 – 60,2) was determined, that was most reliably found (р = 0,008) in children with syntropic functional biliary disorders and was associated with a wide range of comorbid pathology (р = 0,002) and pronounced dysplastic signs (р = 0,034)
Low resistance Cu[3]Ge compounds formation by the lowtemperature treatment of Cu/Ge system in atomic hydrogen
The research deals with the regularities for Cu[3]Ge compound formation under the low temperature treatment of a double-layer Cu/Ge system deposited on i-GaAs substrate in atomic hydrogen flow. The treatment of a Cu/Ge/i-GaAs system with layer thicknesses, respectively, of 122 and 78 nm, in atomic hydrogen with a flow rate of 10{15} at.·сm{-2} s{-1} for a duration of 2.5{-10} min at room temperature, leads to an interdiffusion of Cu and Ge and formation of a polycrystalline film containing stoichiometric phase Cu[3]Ge. The film consists of vertically oriented grains of dimensions 100-150 nm and has a minimum specific resistance of 4.5 [mu omega] сm. Variation in the treatment duration of Cu/Ge/i-GaAs samples in atomic hydrogen affects Cu and Ge distribution profiles, the phase composition of films formed, and the specific resistance of the latter. As observed, Cu3Ge compound synthesis at room temperature demonstrates the stimulative effects characteristic of atomic hydrogen treatment for both Cu and Ge diffusion and for the chemical reaction of Cu[3]Ge compound generation. Activation of these processes can be conditioned by the energy released during recombination of hydrogen atoms adsorbed on the surface of a Cu/Ge/i-GaAs sample
POROUS METAL-ORGANIC FRAMEWORKS: FROM SYNTHESIS TO FUNCTIONAL PROPERTIES
Lying on the crossing of fundamental inorganic/organic chemistry and development of novel materials, metal-organic frameworks (MOFs) have become one of the most attractive research fields during the past two decades. MOFs can be self-assembled from a large number of metal ions/clusters with organic linkers and can be regarded as multifunctional materials due to a wide range of important properties. MOFs often combine properties caused by specific framework architecture, e.g. permanent porosity, selective gas sorption and separation, and chemical stability, with those ones related to the properties of inorganic building blocks, e.g. luminescence and magnetism. Here we describe our recent results on synthesis, structural characterization and investigation of multifunctional materials based on porous coordination polymers.This work was supported by the Russian Foundation for Basic Research (Grant No. 18-29-04001) and the Russian Science Foundation (Grant No. 19-73-20087)
Understanding hysteresis in carbon dioxide sorption in porous metal-organic frameworks
Two
new isostructural microporous coordination frameworks [Mn3(Hpdc)2(pdc)2] (1) and [Mg3(Hpdc)2(pdc)2] (2) (pdc2– = pyridine-2,4-dicarboxylate) showing
primitive cubic (pcu) topology have been prepared and
characterized. The pore aperture of the channels is too narrow for
the efficient adsorption of N2; however, both compounds
demonstrate substantially higher uptake of CO2 (119.9 mL·g–1 for 1 and 102.5 mL·g–1 for 2 at 195 K, 1 bar). Despite of their structural
similarities, 2 shows a typical reversible type I isotherm
for adsorption/desorption of CO2, while 1 features
a two-step adsorption process with a very broad hysteresis between
the adsorption and desorption curves. This behavior can be explained
by a combination of density functional theory calculations, sorption,
and X-ray diffraction analysis and gives insights into the further
development of new sorbents showing adsorption/desorption hysteresis
Direct conversion of methane to zeolite-templated carbons, light hydrocarbons, and hydrogen
Efficient direct valorization of methane to value-added chemicals and materials remains an unsolved challenge for modern chemistry and materials science. In this work, we explored direct non-oxidative conversion of methane to hydrogen, hydrocarbons, and valuable zeolite-templated carbon materials. First, using a set of spectroscopy and microscopy characterization tools, we investigated how the reaction conditions influence the process of carbon formation inside the typical zeolite-based catalyst Mo/ZSM-5. Then, we explored the effect of the zeolite topology on the growth of carbon materials from methane decomposition over Mo/MFI, Mo/MOR, Mo/BEA, and Mo/FAU templates. Finally, we applied the obtained insights to prepare high-quality zeolite-templated carbons directly from methane using Fe/BEA and Fe/FAU templates. Altogether, our results represent a carbon-economic method of methane conversion to COx-free hydrogen gas, a mixture of light aliphatic and aromatic hydrocarbons, and valuable carbon materials
Modelling of regulatory factor and managerial impact assessment in the regional economy sectors: a case-study of the Kaliningrad region (Russia)
This article discusses the methodology of developing tools for assessing regulatory factors and managerial impacts on the regional economy and individual sectors and businesses. The potential of projection models is investigated, including balance models, convergence of regional and sectoral projection and compiling reliable and representative data sets capable of describing the current economic situation. An attempt was made to develop a series of models for several regional economies; to that end, the modelling of managerial and regulatory impact assessment was used in combination with the well-known value chain approach. In the interests of effective public administration, one of the requirements is to create sectoral model formats compatible with the regional projection models. Results of pilot modelling managerial and regulatory impacts on Kaliningrad region’s economies are presented through examples of agribusiness, transport, industry, tourism and recreation. Implementation of regulatory impact modelling in the framework of the suggested approach is proved for other regions. The main advantage of the developed models for the regional management is their ability to reduce uncertainty in decision-making due to obtaining estimates of the impact of the decisions on the changing situation and the conditions for the development of sectors and industries
Crystal structures of binuclear Bi(III) chloride and bromide complexes with some cations — Alkylated pyridine derivatives
© 2017, Pleiades Publishing, Ltd. By a reaction of [BiX 6 ] 3– with salts of various N-alkylated pyridine derivatives in 2M HX (X = Cl, Br), (N-BzPy) 4 [Bi 2 X 10 ] complexes (X = Cl (1), Br (2), (4-MePyH) 4 [Bi 2 Cl 10 ] (3)) are obtained and structurally characterized
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