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Structure-activity relationship in water-gas shift reaction over gold catalysts supported on Y-doped ceria

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作者： tatyana Tolstaya

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Journal of Rare Earths 2019年第4期37卷 383-392页

作者： tatyana Tabakova Lyuba Ilieva Ivan Ivanov Maela Manzoli Rodolfo Zanella Petya Petrova Zbigniew Kaszkur Institute of Catalysis Bulgarian Academy of Sciences Department of Drug Science and Technology & Centre for Nanostructured Interfaces and Surfaces University of Turin Centro de Ciencias Aplicadas y Desarrollo Tecnologico Universidad Nacional Autonoma de Mexico Institute of Physical Chemistry PAS

The utilization of pure hydrogen as an energy source in fuel cells gave rise to renewed interest in developing active and stable water-gas shift catalysts. Gold catalysts have proven to be very efficient for water-gas shift reaction at low temperature. The aim of the present study was to investigate the effect of:(i) different preparation methods(impregnation and coprecipitation) to obtain a modified ceria support,and(ii) the amount of Y_2 O_3(1.0 wt%, 2.5 wt%, 5.0 wt% and 7.5 wt%) as dopant on the water-gas shift activity of Au/CeO_2 catalysts. An extended characterization by means of S_(BET), XRD, HRTEM/HAADF, FTIR,H_2-TPR and CO-TPR measurements in combination with careful evaluation of the catalyst behavior allowed to shed light on the parameters governing the water-gas shift activity. The catalysts show very high activity(>90% CO conversion) in the temperature range 180-220 ℃,with a slightly better performance of the gold catalysts on supports prepared by impregnation. The decreased activity with increasing Y_2 O_3 concentration is related to the hindering of oxygen mobility due to ordering of surface oxygen vacancies in vicinity of segregated Y^(3+). The effect of catalyst pre-treatments and the stability of the best performing samples were examined as well.

关键词： Gold catalyst Water gas shift reaction Doped ceria Yttrium Hydrogen production Rare earths

Monitoring cellular metabolism of 3T3 upon wild type E. coli infection by mapping NADH with FLIM

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Chinese Optics Letters 2010年第10期8卷 931-933页

作者： tatyana Buryakina Pin-Tzu Su Vladimir Gukassyan Wan-Jr Syu Fu-Jen Kao Institute of Biophotonics National Yang-Ming University Institute of Microbiology and Immunology National Yang-Ming University Department of Photonics National Sun Yat-Sen University

Fluorescence lifetime imaging microscopy （FLIM） has gained popularity as a sensitive technique to monitor the functional/conformational states of reduced nicotinamide adenine dinucleotide （NADH）, one of the main compounds of oxidative phosphorylation. In this letter, we apply the technique to characterize the metabolic changes in mouse embryonic fibroblast 3T3 cells upon bacterial infection. A gradual shortening of the decaying time constants in both the short and the long lifetime components of NADH＇s autofluorescence is detected. The ratio of the short and the long lifetime components＇ relative contributions, however, shows a rapid increase, indicating the rise of cellular metabolic activity over the course of infection.

关键词： Amides Cell culture Phosphorylation Tissue

Assessment of palmar subcutaneous tissue vascularization in patients with Dupuytren's contracture

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World Journal of Orthopedics 2018年第9期9卷 130-137页

作者： Nathalia Shchudlo tatyana Varsegova tatyana Stupina Tamara Dolganova Michael Shchudlo Nathalia Shihaleva Vadim Kostin Clinics and Experimental Laboratory for Reconstructive Microsurgery and Hand Surgery Russian Ilizarov Scientific Center "Restorative Traumatology and Orthopaedics" Laboratory of Morphology of Federal State Budget Institution Russian Ilizarov Scientific Center "Restorative Traumatology and Orthopaedics"

AIM To investigate the structural and functional characte-ristics of palmar hypodermal tissue vascularization in Dupuytren's contracture patients of different *** Eighty-seven Dupuytren's contracture patients underwent partial fasciectomy. Twenty-two of them were less than 55 years old(Y-group, n = 22); the others were 55 and older(O-group, n = 65). In surgically excised representative tissue samples, a histomorphometric analysis of the perforating arteries of the palmar aponeurosis and stereologic analysis of hypodermis vascularity were performed. The method of laser flowmetry estimated the microcirculation of the skin of the *** Frequency of cases with rapid development of contracture(less than 5 years) was 13.6% in the Y-group and 40% in the O-group, P < 0.05. The external and luminal diameters of perforating arteries in palmar fascia were decreased more severely in Y. The thickness of intima increased three times compared with healthy control, and the intima/media relation also increased, especially in O. Increased numerical and volumetric micro-vessel densities in hypodermis, percentage of large vessels(more than 12 μm in diameter), and percentage of vessels with signs of periadventitial inflammatory infiltration were noted in Y. The percentage of vessels with adventitial fibrosis was greater in O than in Y. Base capillary flow in Y was increased compared to healthy control subjects and to O, and peak capillary flow was increased in comparison with *** Compared to the O-group, Y-group patients exhibited more severe constrictive remodeling of palmar fascia perforating arteries supplying hypodermis but more expressed compensatory changes of its capillarization.

关键词： Dupuytren’s contracture Laser Doppler flowmetry Hypodermis Histo-morphometry Palmar fascia

Investigation of Cavitation in NaCl Solutions in a Sonochemical Reactor Using the Foil Test Method

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1093-1102页

作者： Michael Kuchinskiy tatyana Lyubimova Konstantin Rybkin Anastasiia Sadovnikova Vasiliy Galishevskiy Institute of Continuous Media Mechanics UB RAS Perm614013Russia Faculty of Physics Perm State UniversityPerm614068Russia

Ultrasonic baths and sonochemical reactors are widely used in industrial applications dealing with surface cleaningand chemical synthesis. The processes of erosion, cleaning and structuring of the surface can be typically controlledby changing relevant influential parameters. In particular, in this work, we experimentally investigate theeffect of NaCl concentration (0–5.5 mol/L) on the erosion of an aluminum foil under ultrasonic exposure at afrequency of 28 kHz. Special attention is paid to the determination of cavitation zones and their visualizationusing heat maps. It is found that at low NaCl concentration (0.3 mol/L), the foil destruction rate is higher thanin distilled water. At higher concentrations of salt, cavitation takes place mainly in the upper part of the container.

关键词： Ultrasound NaCl solution foil test cavitation activity

Influence of 10-(6-plastoquinonyl) decyltriphenylphosphonium on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced hyperglycemia

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World Journal of Diabetes 2019年第12期10卷 546-559页

作者： Aleksander A Agarkov tatyana N Popova Yana G Boltysheva Department of Medical Biochemistry and Microbiology Voronezh State University

BACKGROUND It is known that under conditions of tissue tolerance to insulin,observed during type 2 diabetes mellitus(DM2),there is an increased production of reactive oxygen ***,the free radicals can initiate lipid peroxidation(LPO)in lipoprotein *** concentration of LPO products can influence the state of insulin receptors,repressing their hormone connection activity,which is expressed as a reduction of the glucose consumption by *** is possible that reduction in glucose concentration during administration of 10-(6-plastoquinonyl)decyltriphenylphosphonium(SkQ1)to rats with DM2 may be related to the antioxidant properties of this *** To establish the influence of SkQ1 on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced *** To induce hyperglycemia,rats were fed a high-fat diet for 1 mo and then administered two intra-abdominal injections of streptozotocin with a 7-d interval at a 30 mg/kg of animal weight dose with citrate buffer equal to pH ***1 solution was administered intraperitoneally at a 1250 nmol/kg dose per *** samples were taken from control animals,animals with experimental hyperglycemia,rats with streptozotocin-induced glycemia that were administered SkQ1 solution,animals housed under standard vivarium conditions that were administered SkQ1,rats that were administered intraperitoneally citrate buffer equal to pH 4.4 once a week during 2 wk after 1-mo high-fat diet,and animals that were administered intraperitoneally with appropriate amount of solution without SkQ1(98%ethanol diluted eight times with normal saline solution).To determine the intensity of free radical oxidation and total antioxidant activity,we used the biochemiluminescence *** hydratase(AH),superoxide dismutase,and catalase activities were estimated using the Hitachi U-1900 spectrophotometer supplied with *** amount of citrate was determined by means of the Natel

关键词： Diabetes mellitus Free radical oxidation Antioxidants 10-(6-plastoquinonyl)decyltriphenylphosphonium

Formation of Water Quality of Surface Water Bodies Used in the Material Processing

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Fluid Dynamics & Materials Processing 2024年第4期20卷 815-828页

作者： tatyana Lyubimova Anatoly Lepikhin Yanina Parshakova Irina Zayakina Alibek Issakhov Laboratory of Computational Fluid Dynamics Laboratory Institute of Continuous Media Mechanics UB RASPerm614068Russia Laboratory of Land Hydrology Problems Mining Institute UB RASPerm614000Russia Department of Theoretical Physics Perm State UniversityPerm614990Russia Department of Mathematical and Computer Modeling Al-Farabi Kazakh National UniversityAlmaty050040Republic of Kazakhstan

In the process of production or processing of materials by various methods,there is a need for a large volume of water of the required *** in many regions of the world,there is an acute problem of providing industry with water of a required *** solution is an urgent and difficult *** water quality of surface water bodies is formed by a combination of a large number of both natural and anthropogenic factors,and is often significantly heterogeneous not only in the water area,but also in *** a rule,the water supply of large industrial enterprises is located along the river *** are the most important nodes of river *** the mechanism of transport of pollutants at the confluence of rivers is critical for assessing water *** recent years,thanks to the data of satellite images,the interest of researchers in the phenomenon of mixing the waters of merging rivers has *** nature of the merger is influenced by the formation of transverse *** the framework of this work,a study of vorticity,as well as the width of the mixing zone,depending on the distance from the confluence,the speeds of the merging rivers and the angle of confluence was carried *** the consumer properties of water are largely determined by its chemical and physical indicators,the intensity of mixing,determined largely by the nature of the secondary circulation,is of fundamental importance for assessing the distribution of hydrochemical indicators of water quality in the mixing *** characteristics are important not only for organizing water intake for drinking and technical purposes with the best consumer properties,but also for organizing an effective monitoring system for confluence zones.

关键词： Water for material processing water quality formation of transverse circulation

Specific structural features of LnZrOx(Ln:La, Sm) mixed oxides prepared by different methods

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Progress in Natural Science:Materials International 2018年第4期28卷 437-446页

作者： tatyana Kuznetsova Tamara Kriger Yurii Chesalov ANDrey Boronin Arcadii Ishchenko Pavlos K.PANDis Vladimir Krivensov Galina Litvak tatyana Larina Vladislav Sadykov Vassilis N.Stathopoulos Boreskov Institute of Catalysis Novosibirsk State University Laboratory of Chemistry and Materials Technology Department of Electrical Engineering School of Technological Applications Technological Education Institute of Sterea Ellada

LnZrOx(Ln: La, Sm) mixed oxides of Ln: Zr = 1 were prepared by different methods(complex polymerized method, sorption of cations on starch from aqueous salt solution and conventional co-precipitation with additional redispersion of precipitate by ultra sound) and calcined at 700–1300 °C. Their specific structural features and changes were studied and discussed. Various characterization methods were used such as X-ray diffraction,Electron microscopy, Fourier-transform infrared and Raman spectroscopy, UV–Vis spectroscopy, X-Ray absorption fine structure and X-ray photoelectron *** formation of pyrochlore structure occurred at 1100–1300 °C from fluorite-like pseudocubic phase ZrO2regardless the method of preparation. This phase had a block-like structure consisting of ZrO2nanocrystals stabilized by Ln cations and residual anions such as hydroxyls and carbonates. The desorption of such anions with heating already started at 900 °C and lead to local changes of Zr cations coordination to octahedral and to the formation of pyrochlore nanodomains inclusions within fluorite-like phase. The increased cation mobility and further elimination of anions caused by further heating was accompanied by the formation of bulk pyrochlore phase at 1100–1300 °C. Even after calcination at 1300 °C the local microheterogeneity as well as defects were identified at domains boundaries or sintered microstructure. These specific features of the formed pyrochlores depend on the method of preparation.

关键词： Fluorites Pyrochlores Synthesis Powders Structure

Electron probe microanalysis оf experimentally stimulated osteoarthrosis in dogs

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World Journal of Orthopedics 2017年第9期8卷 681-687页

作者： tatyana Stupina Michael Shchudlo Michael Stepanov Laboratory of Morphology FSBI Russian Ilizarov Scientific Center "Restorative Traumatology and Orthopaedics"

AIM To develop methods of articular cartilage preparation for X-ray-electron probe microanalysis and to study its elements content in experimental *** Twenty dogs aged 2-8 years were divided in research(aged 2 years, induction of osteoarthrosis-IOA) and intact group. Intact group included three subgroups(aged 2, 5 and 8 years). Samples of cartilage after araldite saturation and pouring were partially cut into semithin sections stained with methylene blue and with methylene blue-basic fuchsin. Their smooth surfaces were investigated by X-ray-electron probe microanalysis. Spatial distribution of sulfur, calcium and phosphorus and their concentrations(weight %) were *** X-ray electron probe microanalysis revealed non-uniformsulfur distribution in cartilage of intact animals: Its content increases from superficial zone to deep one, this regularity was preserved in animals with IOA. Differences of IOA with spontaneous chondropathy were revealed. Spontaneous aging was characterized by calcium and phosphorus storage in deep and calcified zones and compensatory increase of sulfated glycosaminoglycans in intermediate and deep cartilage zones as evidenced by the metachromatic reaction and microanalysis data. Unlike spontaneous chondropathy connected with aging in experimentally stimulated osteoarthrosis more intensive storage of calcium but minor phosphorus in intermediate zone were marked. In IOA the calcified cartilage thinning and osteoclastic resorption are apparent with few changes of elements composition; the only difference from control is minority phosphorus *** The obtained results demonstrate specific tricks of X-ray electron probe microanalysis and its possibility in the research of mechanisms of articular cartilage alterations in osteoarthrosis.

关键词： Osteoarthrosis Articular cartilage Dog X-ray electron probe microanalysis