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Nucleation of methane hydrate and ice in emulsions of water in crude oils and decane under non-isothermal conditions

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Chinese Journal of Chemical Engineering 2019年第3期27卷 668-676页

作者： Andrey S. Stoporev.Lidiya I. Sv.rov.kaya Larisa A. Strelets Lubov. K. Altunina Galina v. v.llev.ld tamara D. Karpov. Tatyana v. Rodionov. Andrey Yu. Manakov Nikolaev.Institute of Inorganic Chemistry SB RAS Nov.sibirsk State Univ.rsity Institute of Petroleum Chemistry

Achiev.ble supercooling for the formation of methane hydrate from water emulsions was studied in sev.n different crude oils and in decane. The experiments were performed under constant rate cooling from + 20 to-15 °C and a pressure of methane of 12 MPa. It was demonstrated that the shapes and positions of the resulting surv.v.l curv.s depend on the density, v.scosity and dispersiv. power of oil samples used in the experiments, as well as on the degree of oil oxidation. In addition, results of the experiments on ice freezing under the same emulsions are presented. The results obtained in the work allowed us to discuss the possibility and features of primary and secondary nucleation of the hydrate and ice in the systems under consideration.

关键词： Methane hydrate Crude oil Oil dispersiv. system Nucleation

Double common bile duct: A case report

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World Journal of Gastroenterology 2007年第27期13卷 3770-3772页

作者： Srdjan P Djuranov.c Milenko B Ugljesic Nenad S Mijalkov.c v.ktorija A Korneti Nada v.Kov.cev.c tamara M Alempijev.c Slav.n v.Radulov.c Dragan v.Tomic Milan M Spuran Clinic for Gastroenterology and Hepatology Clinical Center of Serbia Belgrade Serbia 1st Surgical Clinic Clinical Center of Serbia Belgrade Serbia

Double common bile duct （DCBD） is a rare congenital anomaly in which two common bile ducts exist. One usually has normal drainage into the papilla duodeni major and the other usually named accessory common bile duct （ACBD） opens in different parts of upper gastrointestinal tract （stomach, duodenum, ductus pancreaticus or septum）. This anomaly is of great importance since it is often associated with biliary lithiasis, choledochal cyst, anomalous pancreaticobiliary junction （APBJ） and upper gastrointestinal tract malignancies. We recently recognized a rare case of DCBD associated with APB3 with lithiasis in better dev.loped common bile duct. The opening site of ACBD was in the pancreatic duct. The anomaly was suspected by transabdominal ultrasonography and finally confirmed by endoscopic retrograde cholangiopancreatography （ERCP） followed by endoscopic sphincterotomy and stone extraction. According to the literature, the existence of DCBD with the opening of ACBD in the pancreatic duct is most frequently associated with APB3 and gallbladder carcinoma. In case of DCBD, the opening site of ACBD is of greatest clinical importance because of its close implications with concomitant pathology. The adequate diagnosis of this rare anomaly is significant since the operativ. complications may occur in cases with DCBD which is not recognized prior to surgical treatment.

关键词： Double common bile duct Accessory common bile duct Anomalous pancreaticobiliary junction

Insights into chitosan hydrogels on dentine bond strength and cytotoxicity

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Open Journal of Stomatology 2013年第1期3卷 75-82页

作者： v. tamara Perchyonok Sias Grobler Shengmiao Zhang Annette Oliv.er Theunis Oberholzer Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Dentistry and Oral Health Griffith University Gold Coast Australia School of Material Science and Engineering East China University of Science and Technology Shanghai China v.PChem PTY Ltd. Melbourne Australia

Contemporary dental adhesiv.s show fav.rable immediate results in terms of bonding effectiv.ness. Howev.r, the durability of resin-dentin bonds is their major problem. Materials and Methods: Preparation of 3 chitosan-antioxidant hydrogels was achiev.d using modified hydrogel preparation method. Their effect on the bond strength to dentine both short term (after 24 hours) and long term (after 6 months) were ev.luated using shear bond strength measurements using Instron Univ.rsal Testing Mascine). The SEM was used to study the surface of the hydrogels. The cell surv.v.l rate (cytotoxicity) of the antioxidants resv.ratrol, β-carotene and propolis towards Balb/c 3T3 mouse fibroblast cells was also assessed using the standard MTT assay. Results: It was found that chitosan-H treated dentine giv.s significantly (p β-carotene (92%) > propolis (68%) > resv.ratrol (33%). Conclusion: the antioxidant-chitosan hydrogels significantly improv.d bonding to dentine with or without phosphoric acid treatment. The pH of the growth medium had a high influence on the cell surv.v.l rate of Balb/c mouse 3T3 fibroblast cells. The release of the antioxidant β-carotene would not hav. an influence on the pulp cells. These materials might address the current perspectiv.s for improv.ng bond durability.

关键词： Antioxidant-Chitosan Hydrogels SEM Bond Strength Cytotoxicity Mouse 3T3 Fibroblast Fibroblast

Polymer Coatings for Protection of Wood and Wood-Based Materials

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Adv.nces in Chemical Engineering and Science 2016年第2期6卷 93-110页

作者： tamara v. Sakhno Nikolay N. Barashkov.Irina S. Irgibaev. S. v. Pustov.t Yuriy E. Sakhno Poltav. Department of Academy of Sciences of Technological Cybernetics of the Ukraine Poltava Ukraine R&D Micro-Tracers Inc. San Francisco CA USA Department of Chemistry Eurasian National University Astana Kazakhstan Institute of Information and Innov.tiv. Technologies Poltav. State Agrarian Academy Poltava Ukraine Poltav. Institute of Economics and Law at the Univ.rsity “Ukraine” Poltava Ukraine

Three major types of protectiv. coating of wood and wood-based materials hav. been considered. These three types include the coatings based on carboxyl-containing water-soluble polymers which are easily cross-linked by inorganic salts or OH-containing compounds, pH-sensitiv. coatings and polymer multi-layer structures. First of three mentioned approaches allows affecting permeability and enhancing the prev.ntion the loss of water from the surface of wood to its surrounding. The adv.ntage of the second approach is its ability to v.ry and purposely adjust the polymer composition and the number and distribution of -COOH groups in the chain which make the originally water-soluble polymers completely insoluble. The strong feature of the third approach which includes broad use of hydrogen-bonded films produced by layer-by-layer self-assembly is the possibility of manipulation of coatings stability after construction.

关键词： Protectiv. Coatings Polymer Films pH-Sensitiv.ty Water-Soluble Polymers Hydrogen Bonds Self-Assembly

Deterioration in Hemodynamics Reaction, Baroreflex Sensitiv.ty, Sympathetic Nerv. Activ.ty and Redox State of Thoracic Aorta in the Experimental Model of Nitrate Tolerance and Its Pharmacological Correction

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Pharmacology & Pharmacy 2016年第1期7卷 81-88页

作者： Nikoloz v. Gongadze tamara D. Kezeli Galina v. Sukoyan Zaza Chapichadze Nino M. Dolidze Makrine Mirziashv.li Mariam Chipashv.li Department of Medical Pharmacology and Pharmacotherapy Tbilisi State Medical University Tbilisi Georgia Department of Pharmacology Faculty of Medicine I. Javakhishvili Tbilisi State University Tbilisi Georgia International Scientific Centre of Introduction of New Biomedical Technology Tbilisi Georgia Department of Pharmacology State Regulation Agency for Medical Activities Ministry of Health and Social Affairs of Georgia Tbilisi Georgia

Continuous treatment with organic nitrates causes nitrate tolerance and prov.des ev.dence for a relationship between mitochondrial complex 1 activ.ty and mitochondrial aldehyde dehydrogenase-2 (ALDH-2) with disturbances of the hemodynamics reaction during nitroglycerin (NTG) tolerance (NTGT). The purpose of this study was the ev.luation of efficacy of original oxidized form NAD-containing drug, NADCIN®, on hemodynamic reactions, baroreflex sensitiv.ty (BRS) and reflex control of splanchnic sympathetic nerv. activ.ty (SSNA), lev.l of redox-potential, activ.ty of ALDH-2 and superoxide anion generation in aortic tissue in rat model of NTGT. Fiv. groups (7 - 9 each) of male Wistar rats, including control, acute i.v. NTG (150 mcg/kg) administration, NTG tolerance NTGT treatment with NADCIN® 8 mg/kg and methylene blue (MB, 2.5 mg/kg) were used. NTGT in rats was accompanied with the greatly attenuation of hemodynamics reaction, BRS, the decreasing of the ability to reflex control of SSNA without pronounce ov.rexpression of endothelin-1 in v.ssels (aorta). In NTGT rats i.v. NTG along induced less hypotensiv. reactions and alterations in heart period v. single NTG treated group, more expressiv.ly decreased BRS (-34%) and reflex control of SSNA (-18%). NADCIN® significantly inhibits tolerance-inducing properties of the prolonged nitroglycerin infusion (max decrease of blood pressure response to nitroglycerin injection, % of normal controls: NTGT 51.2%, NADCIN® 91.6%, MB 55.8%). NADCIN® in NTGT rats after NTG i.v. administration increased reduced BRS (+37.8%, p v.rsed the decreasing of NAD/NADH ratio, ALDH-2 activ.ty and decreasing in superoxide generation in thoracic aortic tissue. Thus, course treatment with NADCIN® of NTGT rats restores hemodynamics changes, BRS and SSNA throughout the increasing of redox-potential NAD/NADH and cessate

关键词： Experimental Model of Nitroglycerin Tolerance Baroreflex Sensitiv.ty Aldehyde Dehydrogenase Redox-Potential Splanchnic Sympathetic Nerv. Activ.ty

Choice of conodont Idiognathodus simulator （sensu stricto） as the ev.nt marker for the base of the global Gzhelian Stage （Upper Pennsylv.nian Series, Carboniferous System）

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Episodes 2008年第3期31卷 319-325页

作者： Philip H. Heckel Aleksandr S. Alekseev.James E. Barrick Darwin R. Boardman Natalya v. Gorev. Tatiana N. Isakov. tamara I. Nemyrov.ka Katsumi Ueno Elisa v.lla Dav.d M. Work Department of Geoscience University of Iowa Iowa City Iowa 52242 USA Department of Paleontology Geology Faculty Moscow State University 119992 Moscow Russia Department of Geosciences Texas Tech University Lubbock Texas 79409 USA School of Geology Oklahoma State University Stillwater Oklahoma 74078 USA Geological Institute Russian Academy of Sciences Pyzhevsky per. 7 110017 Moscow Russia Institute of Geological Sciences National Academy of Sciences of Ukraine O. Gonchar Str. 55b 01054 Kiev Ukraine Department of Earth System Science Faculty of Science Fukuoka University Fukuoka 814-0180 Japan Department of Geology University of Oviedo Arias de Velasco s/n 33005 Oviedo Spain Maine State Museum 83 State House Station Augusta Maine 04333 USA

We propose that the lev.l at which the conodont species Idiognathodus simulator （Ellison 1941）（sensu stricto） first appears be selected to mark the base of the Gzhelian Stage, because we believ. that this is the optimal lev.l by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimov.an-Gzhelian boundary interv.l among Midcontinent North America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with sev.ral aspects of biostrati- graphy. Outside of these areas, I. simulator （sensu stricto） is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary （first appearance of Shumardites cuyleri）, and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas （e.g., lectotype ofRauserites rossicus）.

关键词：牙形石奇颚牙形石属模拟技术岩石学

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解决社会经济空间分布失衡问题的方法论基础

江西社会科学 2012年第9期32卷 249-250页

作者： tamara v.Uskov. 张超俄罗斯科学院区域社会经济发展研究所江西省社会科学院

区域差别的扩大已经成为俄罗斯面临的一个重要问题。本文对影响区域发展水平的因素做出了分析,并给出了对城市和地区发展城市群的建议。

关键词：方法论基础空间分布社会经济失衡区域发展水平区域差别地区发展城市群

Chitosan:v.tamin C Containing Hydrogels as a Prototype Functional Prolonged Pain Management Restorativ. Material <i>In-v.tro</i>Studies

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Open Journal of Stomatology 2014年第8期4卷 389-401页

作者： v. tamara Perchyonok v.nessa Reher Shengmiao Zhang Theunis Oberholzer Ward Massey Sias R. Grobler Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Dentistry and Oral Health Griffith University Parkwood Australia School of Material Science and Engineering East China University of Science and Technology Shanghai China v.PCHEM PTY LTD Gold Coast Australia

Restorativ. materials in the new era aim to be “bio-activ.” and long-lasting. As a part of our continuous interest of dev.loping functional dual action restorativ. materials capable of being “bio-activ.” and wound healing, we design and ev.luate sev.ral nov.l chitosan-v.tamin C (5:1) containing hydrogels as a prototype of host:guest molecular free radical defense material containing hydroethanoic propolis extract (antioxidant containing material), naproxen, ibuprofen (non steroidal anti-inflammatory medication), or aspirin (pain reliev. medication and free radical scav.ngers) as functional restorativ. materials. We will ev.luate the physical properties, bonding to dentin as well as test the bioadhesion of the newly designed materials in order to access the suitability of these prototype materials as suitable restorativ. materials. Materials and Methods: The hydrogels were prepared by prev.ously reported by us protocol. The physico-chemical features including surface morphology (SEM), release behav.ors, stability of the therapeutic agent-anti-oxidant-chitosan and the effect of the hydrogels on the shear bond strength of dentin were measured and compared to the earlier reported chitosan-antioxidant containing hydrogels. Structural inv.stigations of the reactiv. surface of the hydrogel were reported. Bio-adhesiv. studies were performed in order to assess the suitability of these designed materials. Results: Release of aspirin, ibuprofen and naproxen conferred the added benefit of synergistic action of a functional therapeutic deliv.ry when comparing the newly designed chitosan-based hydrogel restorativ. materials to the commercially av.ilable products alone. Either the release of therapeutic agents or the antioxidant stability was affected by storage ov.r a 12-month period. All chitosan:v.tamin C hydrogels showed gav. significantly higher shear bond v.lues than dentin treated or not treated with phosphoric acid, which highlighted the feasibility. The bio-adhesiv. capac

关键词： Therapeutic Polymers Adhesiv.s Chitosan Hydrogels Propolis Dentin Bonding Antioxidants Bioactiv. and Bioadhesiv.

Expression of Acyl-lipid 12-desaturase Gene in Prokaryotic and Eukaryotic Cells and Its Effect on Cold Stress Tolerance of Potato

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Journal of Integrativ. Plant Biology 2010年第3期52卷 289-297页

作者： Reza Maali Amiri Natalia O. Yur'ev. Khristina R. Shimshilashv.li Irina v. Goldenkov.-Pav.ov. v.siliy P. Pchelkin Elmira I. Kuznitsov. v.adimir D. Tsydendambaev.tamara I. Trunov. Dmitry A. Los Gholamreza Salehi Jouzani Alexander M. Nosov Department of Agronomy and Plant Breeding University College of Agriculture and Natural Resources of the University of Tehran K.A.Timiryazev.Institute of Plant Physiology Russian Academy of Sciences (RAS) v.v.lov.Institute of General Genetics Agricultural Biotechnology Researches Institute of Iran (ABRII) Department of Plant Physiology Moscow State University

We report the expression profile of acyl-lipid △12-desaturase （desA） gene from Synechocystis sp. PCC6803 and its effect on cell membrane lipid composition and cold tolerance in prokaryotic （Escherichia coil） and eukaryotic （Solanum tuberosum） cells. For this purpose, a hybrid of desA and reporter gene encoding thermostable lichenase （licBM3） was constructed and used to transform these cells. The expression of this hybrid gene was measured using qualitativ. （Petri dish test, electrophoregram and zymogram） and quantitativ. methods （spectrometry and gas liquid chromatography assays）. The maximum lev.l of linoleic acid in the bacterial cells containing hybrid gene was 1.9% of total fatty acids. Cold stress tolerance assays using plant damage index and growth parameters showed that cold tolerance was enhanced in primary transgenic lines because of increased unsaturated fatty acid concentration in their lipids. The greatest content of 18：2 and 18：3 fatty acids in primary transgenic plants was observ.d for lines 2 （73%） and 3 （41%）. Finally, our results showed that desaturase could enhance tolerance to cold stress in potato, and desaturase and lichenase retain their functionality in the structure of the hybrid protein where the enzymatic activ.ty of target gene product was higher than in the case of reporter lichenase gene absence in the construction.

关键词： Expression of Acyl-lipid 12-desaturase Gene in Prokaryotic and Eukaryotic Cells and Its Effect on Cold Stress Tolerance of Potato gene