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Journal of Materials Science & Technology 2015年第9期31卷 881-887页

作者： Camelia Matei Ghimbeu aleksandr I.Egunov Andrey S.Ryzhikov Valeriy A.Luchnikov Institut de Science des Matériaux de Mulhouse

Ensembles of freeze-dried self-rolled polymer micro-scrolls are explored as template media for produc- ing carbon-iron based composites with fibrous morphology. Polymer fibres impregnated with furfuryl alcohol and loaded with Fe2O3 particles, were thermally treated under inert atmosphere at 700 ℃ and subsequently analysed by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption. The resulting material has a micro-fibrous mor- phology and is basically composed of metallic Fe^0 and FeO particles, i.e., more than 98 wt% of the carbon/ iron-based composite mass. These particles are held together by amorphous porous carbon foam obtained by in-situ carbonization of the polymer/Fe2O3 composite with evacuation of carbon from the system via COx gases released by carbo-reduction of Fe2O3. The material has significant activity in the reaction of catalytic decomposition of hydrogen peroxide in water solutions.

关键词： Composite materialsPorous carbonPolymersIron particles

Nucleation of dislocations and twins in fcc nanocrystals: Dynamics of structural transformations

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Journal of Materials Science & Technology 2019年第1期35卷 201-206页

作者： aleksandr V.Korchuganov aleksandr N.Tyumentsev Konstantin P.Zolnikov Igor Yu.Litovchenko Dmitrij S.Kryzhevich Elazar Gutmanas Shouxin Li Zhongguang Wang Sergey G.Psakhie Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences National Research Tomsk State University Technion–Israel Institute of Technology Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials.

关键词： Lattice defects Dislocation Nanotwin Atomic model Molecular dynamics simulations

Septic arthritis of the hand: From etiopathogenesis to surgical treatment

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World Journal of Orthopedics 2022年第11期13卷 993-1005页

作者： Konstantin V Lipatov Arthur Asatryan George Melkonyan aleksandr D Kazantcev Ekaterina I Solov’eva Irina V Gorbacheva Alexander S Vorotyntsev Andrey Y Emelyanov General Surgery Department Institute of Clinical Medicine named after N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia General Surgery Department State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115142Russia General Surgery Department The Hospital for War Veterans N3Moscow 129336Russia General Surgery Department I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia

BACKGROUND Septic arthritis of the hand,which is the second most common after damage of the knee joint,remains one of the leading causes of temporary *** inflammation can cause dysfunction of the joint,and in the most severe cases,the need for amputation of the finger may *** results of their treatment today,especially from a functional point of view,cannot be considered *** surgical treatment is extremely important in septic arthritis of the hand,as it helps to prevent cartilage destruction and the development of *** To explore the features of the course of septic arthritis of the hand as well as approaches to surgical treatment and its results,depending on the nature of the damage to the articular *** The results of the treatment of 170 patients with septic arthritis of the hand,which were treated in the period of 2020-2021,were *** of the interphalangeal and metacarpophalangeal joints(MCP)of fingers 1,2,and 3 was more often noted in 147(81.6%)*** most common cause of arthritis was a penetrating injury as a result of household trauma(101,59.4%),animal bite(30,17.6%),and clenched fist injury(15,8.8%).Septic arthritis with contiguous osteomyelitis was observed in 98(54.4%)*** treatment was completed with drainage and irrigation of the *** mobilization was used to restore *** patients with osteomyelitis,it was aimed at the formation of *** was not ***-term results of treatment were assessed in 142(83.5%)patients within 1 mo to 12 mo after discharge from the hospital[the median was 7 mo(IQR:4-9)].RESULTS The most commonly isolated organism was Staphylococcus aureus(35.3%).The median treatment delay in patients without osteomyelitis was 5 d(IQR:4-7);for septic arthritis with contiguous osteomyelitis,it was 14 d(IQR:5-21).Radiography for osteomyelitis within 2 wk was uninformative:41.2%of diagnoses.A single surgical treatment was

关键词： Septic arthritis Osteomyelitis Hand Surgical treatment Neoarthrosis

Demographic ageing,health status and life quality of the elderly in Russia

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China Population and Development Studies 2023年第2期7卷 130-159页

作者： Alla Ivanova Elena Zemlyanova Tamara Sabgayda Victoria Semyonova aleksandr Zubko Irina Kryukova Institute for Demographic Research of the Federal Center of Theoretical and Applied Sociology of the Russian Academy of Sciences(Health and Self-Preservation Behavior Department) st.Fotievad.6k.1119333 MoscowRussia Research Institute of Healthcare Organization and Medical Management of the Moscow Healthcare Department st.Sharikopodshipnikovskaya9115088 MoscowRussia

Within the context of the national policy on the elderly,the paper presents trends in demographic ageing,health and life quality of the elderly in *** and political consequences of the XX century have resulted in significant fluctuations in the number of individual generations,forming a long-term fluctuating trend in demographic ageing in *** historical disproportions have overlapped with regional variations in ageing rates due to significant inter-regional population movements,rural-urban migration,substantial gender differences in trends and scales of mortality and fertility *** a result,levels of demographic ageing in Russia vary more than three-fold,worsening in females and rural *** problems are aggravated by unsatisfactory health status of the elderly,manifested in high burden of chronic diseases(especially cardiovascular diseases),leading to life restrictions up to loss of the ability to ***-tech cardiac surgery contributes to life prolongation and improved physical and psychological ***,during rehabilitation,most patients are reluctant to change their unhealthy lifestyle associated with cardio *** and psychoactive substance abuse(in males)are the risk factors of suicidal behaviour,while accessibility of medications,including sleeping pills,firearms,*** to realization of this *** conditions of the elderly and their access to quality social services are important components of wellbeing in terms of *** satisfactory living conditions,the situation significantly differs by type(urban/rural)and size of the *** microsocial contacts with children,family and friends is a powerful source of psychological comfort and social wellbeing.

关键词： Population ageing National policy on the elderly Age structure Share of the elderly Physical wellbeing Psychological wellbeing Social wellbeing Polymorbidity Comorbidities

Artemia cyst production in Russia

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1436-1450页

作者： Liudmila I.LITVINENKO aleksandr I.LITVINENKO Elena G.BOIKO Kirill KUTSANOV Federal State Unitary Enterprise GosrybcenterTyumenRussia State Agrarian University of Northern Urals

In Western Siberia(Russia) there are about 100 Artemia lakes with total area over 1 600 km *** these lakes are located between 51°–56°N and 61°–82°*** general these lakes are shallow(depth less than 1.5 m),small or medium size(0.1 to 10 km 2);they are chloride;their total salinity is from 40 to 250 g/*** harvesting of cysts per year is only in 20–40 *** Russia 550 tons of dry Artemia cysts(14%–18% of the world production) were harvested *** includes about 350 tons in the Altai region and 200 tons in other *** our regular 20-year study period the cyst harvest was:95 tons in Kurgan;65 tons in Omsk,20 tons in Novosibirsk,20 tons in *** of increasing cyst harvest in Russia are considered in this *** the last 30 years the harvest of cysts in Russia has increased from 7–20 to 500–600 tons.A significant influence of dryness of the year was found on productivity in selected lakes,but taken for all the lakes together,the relationship was not *** optimal salinity for productivity of cysts in the lakes was *** of productivity of the lakes and the harvesting results showed that the stocks of cysts are underutilized by approximately 1.7 times.

关键词：俄罗斯卤虫卵新西伯利亚产量收获期阿尔泰地区产能分析生产力

Chlorine Analysis by Diode Laser Atomic Absorption Spectrometry

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光谱学与光谱分析 2000年第2期20卷 149-155页

作者： Joachim Koch, aleksandr Zybin and Kay Niemax Institute of Spectrochemistry and Applied Spectroscopy (ISAS), Bunsen Kirchhoff Street 11, D 44139 Dortmund, Germany Inst. Spectrochemistry Appl. S. Bunsen-Kirchhoff-Street 11 D-44139 Dortmund Germany

The general characteristics of Diode Laser Absorption Spectrometry (DLAAS) in low pressure plasmas particulary with respect to the detection of non metals are comprehensively recapitulated and discussed. Furthermore, a detector, which is based on DLAAS in a microwave induced low pressure plasma as an alternative technique for halogene specific analysis of volatile compounds and polymeric matrices is described. The analytical capability of the technique is demonstrated on the chlorine specific analysis of ablated polymer fragments as well as gas chromatographically separated hydrocarbons. Since the measurements were carried out by means of a balanced heterodyne detection scheme, different technical noise contributions, such as laser excess and RAM noise could efficiently be suppressed and the registered absorption was limited only by the principal shot noise. Thus, in the case of the polymer analysis a chlorine specific absolute detection limit of 10 pg could be achieved. Furthermore, fundamental investigations concerning the influence of hydrocarbons on the dissociation capability of the microwave induced plasma were performed. For this purpose, the carbon , chlorine and hydrogen specific stoichiometry of the compounds were empirically determined. Deviations from the exspected proportions were found to be insignificant, implying the possibility of internal standardization relative to the response of a reference sample.

关键词： Chlorine analysis Gas chromatography Laser ablation Diode laser atomic absorption spectrometry

基于机器学习的俄罗斯学生汉语声调习得的实验研究

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基于机器学习的俄罗斯学生汉语声调习得的实验研究

作者：萨沙（MITKOV aleksandr）河北师范大学

学位级别：硕士

本研究使用机器学习算法代替传统的实验语音学方法(Praat声学软件和声学专家)来评估第二语言学习者汉语声调的习得情况。具体实验步骤如下:以标准普通话语料库为语料建立训练数据集,工程特征,建立深度神经网络模型,进行模型训练,然后以... 详细信息

本研究使用机器学习算法代替传统的实验语音学方法(Praat声学软件和声学专家)来评估第二语言学习者汉语声调的习得情况。具体实验步骤如下:以标准普通话语料库为语料建立训练数据集,工程特征,建立深度神经网络模型,进行模型训练,然后以6名学习汉语的俄罗斯学生为被试对象,对其给定的汉语单音节的读音进行记录采集,最后使用训练好的模型对被试录音中的单音节声调做出评估,即推断出录音中音节声调的类别及其概率。本文由三部分组成:第一章提出本研究的理论基础和技术路线。首先介绍第二语言学习者习得汉语声调的实验研究中使用的传统方法,然后提出将机器学习作为实验工具的方法,重点介绍神经网络模型的建立过程,选择机器学习模型需要的特征建立模型,并用标准语料进行模型训练。第二章是介绍本研究的实验过程。首先设计被试音节表选基频变化最明显的音节,对6名俄罗斯学生的单音节发音进行录音,并将录音材料作为被试语料。然后将其提供给训练好的模型,最后利用模型对被试语料进行声调评估,得出被试单音节语音的声调类别及其准确率。第三章是实验结果对比分析和实验结论。先利用Praat声学软件对随机抽取的某一个被试语音声调进行分析评估,并将评估结果与机器学习模型作出的声调评估结果进行对比,又将机器学习模型的声调评估结果与第二语言习得领域中前人对俄罗斯学生习得汉语声调的研究结果对比。三者对比的结果发现,机器学习模型的评估结果与利用Praat声学软件进行传统声学实验的评估结果和专家评估的结果基本吻合,因此得出结论:机器学习模型在评估汉语声调发音标准度这一方面可以代替传统声学实验中的专家评估和声学软件,在处理大规模语料时有优势,可以在短时间内迅速处理大量语料。

关键词：实验研究声调俄罗斯学生机器学习

俄罗斯冬季道路状况评价与养护作业方法优化研究

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俄罗斯冬季道路状况评价与养护作业方法优化研究

作者：萨沙（Menshchikov aleksandr）哈尔滨工业大学

学位级别：硕士

交通基础设施对世界上任何经济体的重要性都不容小觑。发达的交通网络是实现经济社会可持续的增长、提升国内外贸易量、降低交通和交易成本以及确保人口自由流动的关键因素。提高单位土地之间的交通联系质量对于拥有大面积土地的国家尤... 详细信息

交通基础设施对世界上任何经济体的重要性都不容小觑。发达的交通网络是实现经济社会可持续的增长、提升国内外贸易量、降低交通和交易成本以及确保人口自由流动的关键因素。提高单位土地之间的交通联系质量对于拥有大面积土地的国家尤其重要,这可以通过创建单一经济空间的需要来解释。俄罗斯在其形成阶段为交通基础设施发展提供载体的历史特征,目前表现为交通可达性水平的区域高度不均衡、道路网络的质量低和一体化程度低进入全球运输空间。如果不解决现有的通信线路问题,就不可能长期在世界市场上提供竞争优势。这项工作的目的是评估俄罗斯冬季的道路状况和维护方法的选择。考虑到俄罗斯气候区II和VIII的柴油成本,将考虑使用基于KAMAZ的组合道路车辆DMK-40清洁路边的积雪和分配沙盐混合物的示例来考虑这个问题。调研需要调研方公司数据,所以整理了一些面试题,整理完后马上进行了面试。在采访期间,获得了必要信息和文献,这些都是免费提供的。此外,还收到了公司工作人员的联系方式,他们将再次申请并获得更多研究信息。由于第三部分预计是最难的,因为它包含了解决部分,因此计划将第二学期的几乎整个学期留给写作。最后一步是起草引言和结论。引言将包含最终论文工作的主要规定,例如目标、目的、相关性、实践意义、理论意义等。结论将包含研究的主要结果。最后一步将是参考书目和内容的汇编,以及参考文献的放置。下一个主要目标是分析俄罗斯冬季道路状况评估和维护方法选择对公路管理效率的经济影响。这个目标的本质是从经济评估和效率的角度考虑企业中已经存在的道路养护作业,它们是如何实施的,并根据获得的数据,对其运作方式进行预测在企业中,是否有利可图,是否有必要。总之,仍然有必要考虑企业需要哪些道路维护业务的优先领域以及如何实施这些领域。最后一个主要目标是制定措施,以改进地区国库机构“公路部”的公路维护业务的实施。为了做到这一点,有必要进行以数字显示经济效率的计算,这将有助于发现不足并提出解决这些问题的建议,或验证管理层行动的正确性。首先也是主要的事情是编写具有正确计算和结论的高质量工作,这些工作以后可能对地区国库机构“公路部”工作有用。预计最终排位工作将在未来带来巨大的收益,最重要的是,它的正确书写将有助于在前期防御和保护中顺利执行。

关键词：清洁路边雪荷载分配沙盐混合物组合道路车辆柴油成本冬季道路条件有效性道路维护操作

Reactive SPS of Al_(2)O_(3)–RE:YAG(RE=Ce;Ce+Gd)composite ceramic phosphors

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Journal of Advanced Ceramics 2023年第5期12卷 1015-1032页

作者： Denis Yu.Kosyanov Anastasia A.Vornovskikh Oleg O.Shichalin Evgeniy K.Papynov Anton A.Belov aleksandra A.Kosianova aleksandr N.Fedorets Andrei A.Leonov Alexey P.Zavjalov Sergey A.Tikhonov Yanbin Wang Ziqiu Cheng Xin Liu Jiang Li Far Eastern Federal University Vladivostok 690922Russia Institute of Automation and Control Processes Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia Laboratory of Methods of Synchrotron Radiation Institute of Solid State Chemistry and MechanochemistrySiberian Branch of the Russian Academy of SciencesNovosibirsk 630128Russia Kamchatka Branch of Geophysical Survey of the Russian Academy of Sciences Petropavlovsk-Kamchatsky 683006Russia Key Laboratory of Transparent Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Ultrafine-grained Al_(2)O_(3)–rare earth:yttrium aluminium garnet(Al_(2)O_(3)–RE:YAG)(RE=Ce;Ce+Gd)composite ceramics were obtained for the first time by reactive spark plasma sintering(SPS)using commercially available initial oxide *** effect of key sintering parameters(temperature,dwell time,and external pressure(P_(load)))on densification peculiarities,structural-phase states,and luminescent properties of composites was studied *** in phase formation and densification between Ce-doped and Ce,Gd-codoped systems were *** of reactive SPS,at which there is partial melting with the formation of near-eutectic zones of the Al_(2)O_(3)–YAG system/coexistence of several variations of the YAG-type phase,were *** corundum–garnet biphasic ceramics with an optimal balance between microstructural and luminescence performance were synthesized at 1425℃/30 min/30–60 *** external quantum efficiency(EQE)of the phosphor converters reached 80.7%and 72%with close lifetime of~63.8 ns,similar to those of commercial Ce:YAG materials,which is promising for further applications in the field of high-power white light-emitting diodes(WLEDs)and laser diodes(LDs).

关键词： alumina–Ce^(3+)-doped yttrium aluminium garnet(Al_(2)O_(3)–Ce:YAG)ceramic phosphors reactive spark plasma sintering(SPS) structural-phase states microstructure luminescence performance

Permafrost distribution and temperature in the Elkon Horst, Russia

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Research in Cold and Arid Regions 2021年第2期13卷 107-122页

作者： Mikhail Zhelezniak QingBai Wu Anatolii Kirillin Zhi Wen aleksandr Zhirkov Vladimir Zhizhin Melnikov Permafrost Institute SB RAS Yakutsk 677000Russia State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesCASLanzhouGansu 730000China

The Elkon Horst is a geological structure that consists of heterogeneous strata with highly variable geocryological and temperature conditions. Gaining accurate knowledge of permafrost distribution patterns within this structure is of both scientific and practical importance. In mountainous terrain, the ground thermal regime is controlled by both surface and subsurface conditions. Surface conditions include snow cover characteristics, the presence or absence of vegetation, vegetation density, etc.. In contrast, subsurface conditions involve rock lithology or petrography, density, quantity and depth of fissures, groundwater, etc.. This article examines ground thermal regimes in various geomorphological settings based on temperature measurement data from geotechnical boreholes. The occurrence and extent of permafrost were evaluated for the entire horst area using direct and indirect methods. The maximum permafrost thickness measured in the Elkon Horst is 330 m, and the estimated maximum is 450 m at higher elevations. Thermophysical properties were determined for the major rock types, and the geothermal heat flux was estimated for the study area. The thermal conductivities were found to vary from 1.47 to 4.20 W/(m·K), and the dry bulk densities to range between 2,236 kg/m~3 and 3,235 kg/m~3. The average geothermal heat flux was estimated to be 44 mW/m~2.

关键词： permafrost ground temperature geothermal heat flux thermal conductivity horst