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Gas-phase hydrogenation influence on defect behavior in titanium-based hydrogen-storage material

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Progress in Natural Science:Materials International 2017年第1期27卷 105-111页

作者： Roman S.Laptev Viktor N.Kudiiarov Yuri S.Bordulev andrey A.Mikhaylov andrey M.Lider Department of General Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising materials for hydrogen storage. However, hydrogen penetration accompanies the exploitation of hydrogen storage alloys. In particular, hydrogen penetration and accumulation in titanium alloys changes their mechanical properties. Therefore, the research works of such materials are mainly focused on improving the reversibility of hydrogen absorption-liberation processes, increasing the thermodynamic characteristics of the alloys, and augmenting their hydrogen storage capacity. In the process of hydrogenation-dehydrogenation, the formed defects both significantly reduce hydrogen storage capacity and can also be used to create effective traps for hydrogen. Therefore, the investigation of hydrogen interaction with structural defects in titanium and its alloys is very important. The present work, the hydrogen-induced formation of defects in the alloys of commercially pure titanium under temperature gas-phase hydrogenation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding intensities If, Idand relative changes of parameters S/S0and W/W0, the peculiarities of hydrogen interaction with titanium lattice defects were investigated in a wide range of hydrogen concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrogen Lattice defects Positron annihilation Positron lifetime Doppler broadening

海城小孤山旧石器时代装饰品与欧亚史前象征主义

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草原文物 2024年第2期 50-62页

作者： А.П.扎比亚科王俊铮阿穆尔国立大学宗教学与历史教研室

辽宁海城小孤山史前遗址的旧石器时代晚期文化层中出土了兽牙穿孔垂饰与骨制小圆盘,其年代约为距今3万年前。这批装饰品与骨制标枪、骨针等人工制品、勒瓦娄哇石核等石器工业,反映了该地区由旧石器时代中期向晚期过渡的历史过程。小孤... 详细信息

辽宁海城小孤山史前遗址的旧石器时代晚期文化层中出土了兽牙穿孔垂饰与骨制小圆盘,其年代约为距今3万年前。这批装饰品与骨制标枪、骨针等人工制品、勒瓦娄哇石核等石器工业,反映了该地区由旧石器时代中期向晚期过渡的历史过程。小孤山遗址出土装饰品在风格特征与工艺技术上与欧亚地区及中国北方的旧石器时代晚期早段装饰品存在明显的相似性。小孤山遗址在时间与空间上确立了现代行为类型在旧石器时代中期向晚期过渡时期的边界,是旧石器时代晚期文化传统由西伯利亚起源中心向周边扩散最重要的代表性遗址之一。小孤山遗址装饰品极大地填补了中国境内史前装饰艺术研究的空白,同时反映了欧亚地区东部早期象征主义活动发展的整体趋势和区域特征。

关键词：小孤山遗址装饰品旧石器时代晚期象征主义中国北方地区

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Visual pathways involvement in clinically isolated syndrome in children

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 382-384页

作者： Vladislav Voitenkov Natalia Skripchenko andrey Klimkin Scientific Research Institute of Children's Infections Professora Popova 9

AIM: To investigate extent and nature of visual pathways involvement in children with clinically isolated syndrome(CIS).METHODS: Forty-seven patients(age 11-17y) with CIS, which later proved to be multiple sclerosis(MS)onset, and 30 controls underwent visual evoked potentials(VEP) investigation within 12 d from the appearance of the first signs of disease. Latency and amplitude of P100 peak were compared with normative data and between ***: In 58% patients, including those without signs of retrobulbar neuritis, significant slowing of conduction along the central visual pathways(P100latency lengthening) is seen. P100 amplitudes drop(signs of axonal damage) are registered less frequently(29% cases).CONCLUSION: The results indicate that visual pathways are often affected in the MS onset; mostly demyelination signs are seen. Despite MRI significance for MS diagnostic, VEPs proved to be still effective in early diagnosis of MS in children.

关键词： visual evoked potentials multiple sclerosis clinically isolated syndrome children visual pathway

Loess deposition in Asia： its initiation and development before and during the Quaternary

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Episodes 2008年第2期31卷 222-225页

作者： andrey E. Dodonov Liping Zhou Geological Institute Russian Academy of Sciences Pyzhevsky 7 119017 Moscow Russia Laboratory for Earth Surface Processes Department of Geography Peking University Beijing 100871 China

Dust is important in the Earth environment system. However; the role of dust in climate change remains largely unknown. A better understanding of the temporal and spatial variability of the dust accumulation in Asia forms an important step towards establishing the link between dust deposition and climate change. Here, a summary is given for the timing of the onset and expansion of loess deposition in Asia beginning in the early, Miocene. Recent progress on some aspects of loess chronology and palaeoenvironmental reconstruction is also reviewed.

关键词：亚洲黄土沉积第四纪地质时代地球环境

Clinical significance of molecular subtypes of gastrointestinal tract adenocarcinoma

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World Journal of Gastrointestinal Oncology 2022年第3期14卷 628-645页

作者： Ekaterina Olegovna Ignatova Evgenii Kozlov Maxim Ivanov Vladislav Mileyko Sofia Menshikova Henian Sun Mikhail fedyanin Alexey Tryakin Ivan Stilidi Department of Second Chemotherapy Federal State Budgetary Institution“N.N.Blokhin National Medical Research Center of Oncology”of the Ministry of Health of the Russian FederationMoscow 115478MoscowRussia Department of Oncogenetics Research Centre for Medical Genetics Research Centre for Medical GeneticsMoscow 115522MoscowRussia OncoAtlas LLC Moscow 121069MoscowRussia Department of Biological and Medical Physics Moscow Institute of Physics and TechnologyMoscow 141700MoscowRussia Department of Anticancer Drug Treatment AO K31 CityMoscow 121552MoscowRussia Pirogov Russian National Research Medical University(Pirogov Medical University) Moscow 117997MoscowRussia

Adenocarcinomas of the gastrointestinal tract(esophagus,stomach,and colon)represent a heterogeneous group of diseases with distinct etiology,clinical features,treatment approaches,and *** are ongoing to isolate molecular genetic subtypes,perform complete biological characterization of the tumor,determine prognostic groups,and find predictive markers to the effectiveness of *** molecular genetic classifications were created for esophageal adenocarcinoma[The Cancer Genome Atlas(TCGA)],stomach cancer(TCGA,Asian Cancer Research Group),and colon cancer(Colorectal Cancer Subtyping Consortium).In 2018,isolation of TCGA molecular genetic subtypes for adenocarcinomas of the gastrointestinal tract(esophagus,stomach,and colon)highlighted the need for further studies and clinical validation of subtyping of gastrointestinal ***,this approach has *** aim of our work was to critically analyze integration of molecular genetic subtyping of gastrointestinal adenocarcinomas in clinical practice.

关键词： Esophageal adenocarcinoma Gastric cancer Colon cancer Gene sequencing,Gene expression profiling Molecular subtypes

A case of vitiligo after COVID-19 vaccination: a possible role of thymic dysfunction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第12期24卷 1141-1150页

作者： Denis KUZNETSOV Oleg KALYUZHIN andrey MIRONOV Valery NESCHISLIAEV Anastasiia KUZNETSOVA G.N.Gabrichevsky Scientific and Research Institute of Epidemiology and Microbiology Moscow 125212Russia I.M.Sechenov First Moscow State Medical University Moscow 119991Russia Perm State Pharmaceutical Academy Perm 614990Russia

During the coronavirus disease 2019(COVID-19)pandemic,vaccines help control the spread of *** date,47 vaccines have been approved,with another 227 candidates in various stages of *** the short period of time since the beginning of their use,evidence has begun to emerge of complications following vaccination in the form of the development or exacerbation of a number of pathological conditions(Block et al.,2022;Haseeb et al.,2022).For example,a population-based study in France identified 1612 cases of myocarditis and 1613 cases of pericarditis requiring hospital treatment within five months of vaccination(le Vu et al.,2022).

关键词： vaccination vaccines

Texture,composition and properties of plugs formed by carbon dioxide hydrate and wax

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Petroleum Exploration and Development 2021年第6期48卷 1462-1470页

作者： SKIBA Sergey SAGIDULLIN Aleksey SHAPOVALOVA Alexandra STRELETS Larisa MANAKOV andrey Nikolaev Institute of Inorganic Chemistry SB RASAc.Lavrentiev Ave.3Novosibirsk 630090Russia Novosibirsk State University Pirogova Str.2Novosibirsk 630090Russia Institute of Petroleum Chemistry SB RAS Akademichesky ave.4Tomsk 634021Russia

Gas hydrates and wax are the major flow assurance problems for the transportation of produced hydrocarbons through ***,in most research works both these two problems are studied *** simultaneous precipitation or deposition of these compounds in pipelines can lead to different mitigation/prevention strategies,the investi-gations in which both these problems are considered simultaneously appeared only *** is no information in the literature on the texture/composition and features of decomposition process of mixed wax/hydrate *** the same time,this information could be useful to understand how to treat the problem of formation of these *** this work,three wax/gas hydrate plugs were collected at quasi-static conditions from a water-in-oil emulsion to study their texture,composition and the features of decomposition *** X-ray diffraction and IR(infrared spectroscopy)analyses showed that the plugs consisted of wax and gas *** and DSC(Differential Scanning Calorimetry)experiments showed that the main part of gas hydrate in the plugs at the ambient pressure started to decompose at about 268 *** temperature was higher than the equilibrium temperature of carbon dioxide hydrate at this pressure,indicating that the gas hydrate in the plugs could be effectively preserved at temperatures below the ice melting point(273.2 K).It was found through observation of the hydrate decomposition process in the plugs under the microscope that the gas in the samples released in small bubbles,while the hydrate particles were not visible at this magnification,indicating that the hydrate was indeed highly dispersed in the samples.A residual wax was jelly-like after decomposition of hydrate in all the *** experiments showed that the plugs residues after decomposition of the hydrates had higher yield points and viscosities than the initial waxy crude oil origi-nally used for the experiments.

关键词： carbon dioxide hydrate hydrate/wax plug plug texture hydrate decomposition

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Analysis of porosity influence on the effective moduli of ceramic matrix PZT composite using the simplified finite element model

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Journal of Advanced Dielectrics 2019年第6期9卷 1-9页

作者： Anna Kudimova andrey Nasedkin Institute of Mathematics Mechanics&Computer Science Southern Federal UniversityMiltchakova str.8aRostov on Don 344090Russia

The problem of determining the effective moduli of a ceramic matrix piezocomposite with respect to multiscale porosity was *** solve the homogenization problem,the method of effective moduli in the standard formulation,the finite element method and the ANSYS computational package were *** models of two-phase and three-phase composites consisting of a piezoceramic matrix,elastic inclusions of corundum and pores of various sizes have been *** element models of representative volumes of 3–0 and 3–0–0 connectivities were *** results of computational experiments showed that effective moduli depend quite significantly not only on the volume fractions of inclusions and pores,but also on the structure and size of pores in comparison with the characteristic sizes of inclusions.

关键词： Piezoelectricity three-phase piezocomposite granular inclusion effective modulus representative volume finite element method

Complete Coalescence, Partial Bounce and Rebound: Different Regimes Resulting from the Interaction of a Free Falling Drop with a Target Fluid

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Fluid Dynamics & Materials Processing 2020年第4期16卷 801-811页

作者： Yuli D.Chashechkin andrey Y.Ilinykh Ishlinsky Institute for Problems in Mechanics of the Russian Academy of Sciences Moscow119526Russia

The interaction of a falling drop(diluted aqueous solution of ink in various concentrations)with a target fluid(partially degassed tap water)has been tracked by means of high-resolution video recording and *** experimental setup has carefully been prepared in order to preserve the axial symmetry of initial *** regimes of interaction have been identified accordingly(depending on the drop velocity as controlled by the distance of fall):rapid droplet coalescence,rebound with the conservation of the drop volume and shape,and partial *** findings are recovered and confirmed,and enriched with heretofore unseen observations of complex partial *** extensive set of data is reported to support understanding of the observed dynamics and their repeatability and *** overall study has been carried out with the express intent to spur the future development of detailed mathematical models and numerical methods suited for this kind of problems.

关键词： Drop coalescence bounce spray transport of matter miscible fluids