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The History of N.M.Chernova’s Scientific School of Soil Zoology at the Moscow Pedagogical State University
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作者 Ivan Petrovich VTOROV Anatoly Borisovich BABENKO +4 位作者 Anna Ivanovna BOKOVA Yulia Yurievna DAVYDOVA Mikhail Borisovich POTAPOV Alexei Vyacheslavovich UVAROV Nataliya Alexandrovna KUZNETSOVA 《Chinese Annals of History of Science and Technology》 2025年第2期133-160,共28页
The article reviews the history and scientific contributions of the soil zoology school at Moscow Pedagogical State University,founded by Academician Mercury Sergeevich Gilyarov and led by Professor Nina Mikhailovna C... The article reviews the history and scientific contributions of the soil zoology school at Moscow Pedagogical State University,founded by Academician Mercury Sergeevich Gilyarov and led by Professor Nina Mikhailovna Chernova.A key theoretical contribution from this school was the development of succession theory,which describes changes in soil invertebrate communities during plant litter decomposition.The school’s primary research focus has been on soil microarthropods,particularly springtails(Collembola)and mites—groups that are crucial for soil fertility and bioindication yet remain understudied.We trace the school’s progress in the taxonomy,faunistic studies,and ecology of soil invertebrates,emphasizing its foundation in field studies and laboratory experiments.Though its development was further strengthened through national and international collaborations,many of N.M.Chernova’s seminal ideas are not widely known outside Russia due to language barriers and limited access to publications.Her students continue to address this issue while advancing the study of soil zoology,ecology,and its history. 展开更多
关键词 history of soil zoology Nina Mikhailovna Chernova scientific school Moscow Pedagogical State University soil microarthropods Collembola/springtails succession theory agricultural ecology
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Molecular-Genetic Characterization of Human Rotavirus A Strains Circulating in Moscow, Russia(2009–2014) 被引量:4
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作者 Victoria Kiseleva Evgeny Faizuloev +9 位作者 Elena Meskina Anna Marova Alexey Oksanich Tatiana Samartseva Georgy Bakhtoyarov Natalia Bochkareva Nikolay Filatov Andrey Linok Yulia Ammour Vitaly Zverev 《Virologica Sinica》 SCIE CAS CSCD 2018年第4期304-313,共10页
Enteric viruses are the most common cause of acute gastroenteritis (AGE) in young children and a significant public health problem globally. Hospital admissions of children under 5 years of age with diarrhea are pri... Enteric viruses are the most common cause of acute gastroenteritis (AGE) in young children and a significant public health problem globally. Hospital admissions of children under 5 years of age with diarrhea are primarily associated with group A rotavirus (RVA) infection. In this retrospective study, the population structure of viruses linked to AGE etiology in young children hospitalized with AGE in Moscow was evaluated, and molecular characterization of RYA strains was performed. Fecal specimens were collected from children under 5 years old hospitalized with AGE between 2009 and 2014 in Moscow, Russia. Multiplex real-time reverse transcription PCR was used to detect enteric viruses and for G/[P]-genotyping of isolated RVAs. Sequencing of RVA VP7 and VP4 cDNA fragments was used to validate the data obtained by PCR- genotyping. The main causes for hospitalization of children with AGE were RVA (40.1%), followed by noroviruses (11.4%), while adenoviruses, astroviruses, sapoviruses, enteroviruses, and orthoreoviruses were detected in 4.7%, 1.9%, 1.4%, 1.2%, and 0.2% of samples tested, respectively. Nosocomial infections, predominantly associated with RVAs and noroviruses, were detected in 24.8% of cases and occurred significantly more frequently in younger infants. The predominant RVA genotype was G4P[8], detected in 38.7% of RVA-positive cases, whereas genotypes G1P[8], G9P[8], G3P[8], and G2P[4] were found in 11.8%, 6.6%, 4.2%, and 3.3% of cases, respectively. Together, the presence of circulating RVA strains with rare VP7 and VP4 gene variants (G6 and P[9]) highlights the need to conduct continuous epidemiological monitoring of RVA infection. 展开更多
关键词 Acute gastroenteritis (AGE) Rotaviral enteritis Rotavirus vaccine Rotavirus G/[P] genotype MOSCOW
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Algae and Cyanobacteria in Soils of Moscow
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作者 Marina F. Dorokhova Natalia E. Kosheleva Elena V. Terskaya 《American Journal of Plant Sciences》 2015年第15期2461-2471,共11页
Algal-cyanobacterial communities, soil nano- and microfauna, and mycelium of micromycetes were studied in soils of an administrative district of Moscow. To characterize the habitat conditions of microbiota in the soil... Algal-cyanobacterial communities, soil nano- and microfauna, and mycelium of micromycetes were studied in soils of an administrative district of Moscow. To characterize the habitat conditions of microbiota in the soils of different functional zones of the city, the acid-base conditions and the contents of exchangeable and water-soluble nitrogen, mobile heavy metals, and soluble salts were determined. The diversity of species of algal-cyanobacterial communities, the composition of the dominant species, the proportions of different ecological groups of diatom algae, the diversity of soil nano- and microfauna, and the abundance of colorless and colored mycelium in the urban soils were characterized. The analysis of these parameters showed that the degree of technogenic impact on soil microbiota decreases in the following sequence of functional zones of the city: industrial > traffic > residential > recreation. 展开更多
关键词 Urban SOILS SALINIZATION Pollution MICROBIOTA ALGAE CYANOBACTERIA MOSCOW East European Plain
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Radio "Echo of Moscow" (Ekho Moskvy) as a Multimedia Project
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作者 Ekaterina Bolotova Ludmila Bolotova 《Journalism and Mass Communication》 2015年第5期220-224,共5页
The paper deals the popular news-talk radio station "Echo of Moscow" which is one of the most interesting and successful one in Moscow FM range. It provides thorough analysis of different previous and nowadays progr... The paper deals the popular news-talk radio station "Echo of Moscow" which is one of the most interesting and successful one in Moscow FM range. It provides thorough analysis of different previous and nowadays programs and web projects in comparison with main multimedia sphere trends. A particular attention is paid to "Echo of Moscow" web page as multimedia portal strongly packed with different functions such as its integration with social nets. 展开更多
关键词 RADIO radio station Echo of Moscow Ekho Moskvy radio program AUDIENCE interactivity web page MULTIMEDIA social nets
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Moscow and Moscow Region: Ecological Focus for Sustainable Development
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作者 Irina Ivashkina 《Sociology Study》 2012年第7期540-550,共11页
This paper presents some results of sustainable urban-planning development in Moscow Capital Region. Moscow City and Moscow Region (Moscow Oblast) are the parts of the Moscow Capital Region. According to the Constit... This paper presents some results of sustainable urban-planning development in Moscow Capital Region. Moscow City and Moscow Region (Moscow Oblast) are the parts of the Moscow Capital Region. According to the Constitution of Russia, adopted in December 1993, Moscow Region and Moscow City are two independent federal subjects of Russian Federation. The sustainable development of Moscow City and Moscow Region as an integrated regional economic and natural complex which plays the most important part in Russia's economy must be based on the integrated solution to the problems of environmental protection, social equity, and economic feasibility. The latest initiative of Russian Government concerns the creation of the Greater Moscow within the new borders of Moscow. Making the decision on the extension of the city limits and stimulation of the Moscow Agglomeration development provides the real way of resolution of the accumulated problems and provides enormous impetus to the sustainable development. The key task of the environmentally sound development of the Greater Moscow is to relieve the historical center of Moscow City; maintain the rational balance of built-up areas, natural and rural landscapes; ensure joint control of the urban development and economic activity; and create the favorable environment for the population. 展开更多
关键词 Moscow Capital Region ecological and social issues sustainable development urban planning
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Assessment of Mercury in Diagnostic Biomaterials of Different Population Groups in Urban Areas of the Moscow Region
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作者 Anatoly V. Gorbunov Sergey M. Lyapunov +2 位作者 Irina N. Ilchenko Marina V. Frontasyeva Sergey S. Pavlov 《Advances in Microbiology》 2019年第7期571-580,共10页
The results of a survey of different population groups in urban areas of the Moscow Region (industry workers, residents of areas with increased anthropogenic load of mercury and conditionally pristine areas, cohorts o... The results of a survey of different population groups in urban areas of the Moscow Region (industry workers, residents of areas with increased anthropogenic load of mercury and conditionally pristine areas, cohorts of pregnant women and children) to assess the contents of mercury in samples of various diagnostic biomaterials taken during the course of research are presented. Mercury concentrations in venous and umbilical cord blood, urine, hair, and nails were determined by means of instrumental neutron activation analysis and cold vapor atomic absorption spectrometry. Peculiarities of selection, transportation, storage, and preparation for analysis of samples of hair, nails, urine and umbilical venous blood are described. The determined concentrations of mercury in the studied diagnostic biomaterials are compared with normal and thresholds values. Although increased mercury concentrations were observed in some cases, no significant exposure of mercury was evident in general in the study towns. A positive correlation between the degree of consumption of seafood during pregnancy and a high content of mercury in the analyzed diagnostic biomaterials was shown. 展开更多
关键词 MERCURY HAIR NAILS Urine VENOUS and UMBILICAL Cord Blood The Impact The Human
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AN ALABASTER SCULPTED HEADOFPTOLEMY V FROM THE PUSHKIN MUSEUMOFFINEARTS,MOSCOW,ANDHORUSASPECTS OF LATE PERIOD EGYPTIAN AND PTOLEMAIC KINGSHIP
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作者 Ivan A.Ladynin 《Journal of Ancient Civilizations》 2023年第1期1-20,125,共21页
The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be mentioned.The earlier is Bildnisse der ... The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be mentioned.The earlier is Bildnisse der Ptolemaer by H.Kyrieleis,which established a convincing correspondence between the well-attributed images of the Ptolemaic kings on their coins and their mostly uninscribed sculpted images.'The history of the research reveals that although the corpus of Ptolemaic sculpture gradually expanded,due to new finds and new publications,challenges to specific attributions proposed by Kyrieleis often proved to be a failure?A later work deserving a special mention is Portraits of the Ptolemies by P.E.Stanwick,which proposed a well-founded scheme for the evolution of the Ptolemaic royal sculpture dividing it into nine groups(Groups A-E,G making a chronological sequence,Groups F,H-J uncertain and miscellaneous)'Quite expectedly,a problematic issue is the ultimate motive and final result of shifting from one such group to another:a grouping of objects is largely a formal task,and a scholar performing it is unlikely to concentrate simultaneously on the variety of political,ideological,and religious factors that could lie behind the emergence of the groups indicated.The present article aims to offer a tentative explanation for the shift in the style of Ptolemaic sculpture that took place at the cusp of the 3rd and 2nd centuries BC,i.e.,the transition between Stanwick's "Group A"and "Group B." 展开更多
关键词 dividing RELIGIOUS SHIFTING
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Large-Scale Structural and Geodynamic Mapping of Platform Territories on the Example of Moscow
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作者 Anastasia L. Dorozhko Vladimir M. Makeev 《Journal of Earth Science and Engineering》 2013年第8期527-539,共13页
This paper describes principles, methods and results of a large-scale (1: 25,000) structural-geodynamic mapping of Moscow territory. Neotectonic structures of different ranks--elevations and depressions, lineaments... This paper describes principles, methods and results of a large-scale (1: 25,000) structural-geodynamic mapping of Moscow territory. Neotectonic structures of different ranks--elevations and depressions, lineaments and GDAZ (geodynamic active zones) are presented on the map. Geodynamic active zones are linear or isometric crust volumes of different scales that localized spatially, where conditions for tectonic stress concentration and relaxation, and high gradients of movements and rocks deformity are favorable by different reasons. They differ from active faults, which are rare on geodynamic-stable platform territories, by absence of noticeable displacements in rocks and a more geodynamic stability. Nevertheless, GDAZ can be hazard to engineering buildings, since these zones are favorable for developing exogenous (such as erosion, impoundment, karst, sliding, etc.) and endogenous geological processes (such as seismicity, water-fluid permeability and heat flux). They can also become migration and localization channels of nature-anthropogenic pollution. 展开更多
关键词 Neotectonic structures recent geodynamics GDAZ PLATFORM urban territories.
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EARLY PTOLEMAIC COINS FROM THE COLLECTION OF THE STATE HISTORICAL MUSEUM (MOSCOW)
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作者 Svyatoslav V.Smirnov Eugenii V.Zakharov 《Journal of Ancient Civilizations》 2023年第2期191-235,250,共46页
In 2018,the work of one of the leading experts in numismatics of Hellenistic Egypt Catharine C.Lorber’s Coins of the Ptolemaic Empire was out of print.This work significantly complements and,in some ways,revises the ... In 2018,the work of one of the leading experts in numismatics of Hellenistic Egypt Catharine C.Lorber’s Coins of the Ptolemaic Empire was out of print.This work significantly complements and,in some ways,revises the fundamental work of Ioannis N.Svoronos,1 supplementing it with many new details. 展开更多
关键词 DETAILS EGYPT some
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Efficacy of Hypovitaminosis D Correction in Children of the Older Age Group Residing in Moscow
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作者 Zakharova Irina Solovyova Ekaterina +6 位作者 Klimov Leonid Vasilyeva Svetlana Tvorogova Tatyana Sugyan Narine Rakhteenko Alina Kuryaninova Victoria Pludowsky Pawel 《Journal of Health Science》 2017年第6期271-281,共11页
School-aged children and their health conditions, in particular, deficient conditions are not less note worthy than in younger children, while the recognition of present low vitamin D provision in children of all age ... School-aged children and their health conditions, in particular, deficient conditions are not less note worthy than in younger children, while the recognition of present low vitamin D provision in children of all age groups has not still resulted in implementation of mass prophylaxis of hypovitaminosis D. There are several factors on which blood concentration of 25 (OH) D--calcidiol-depends. However, it is evident that among numerous factors we should orient on several most significant and develop correction scheme for the deficient condition in every region. Aim: to assess vitamin D levels in adolescents residing in Moscow, to correct their calcidiol status based on a baseline blood concentration of the transport metabolite. Materials and methods: 769 adolescents aged 11-18 years were examined and their blood concentration of 25 (OH) D was determined. Then, 218 patients were randomized to 2 groups: the treatment group received food supplement "Minisun~ Vitamin D3" in tablets, the control group received placebo. Cholecalciferol dosage was prescribed depending on the baseline calcidiol level in patients. The study continued for 6 months, after that blood was re-withdrawn for calcidiol level. Results: low calcidiol provision was observed among school children: median 25 (OH) D was 16.3 [11.4-20.8] ng/mL, only 5.2% of patients had normal blood concentration of calcidiol. There-examination showed significant differences in vitamin D status in the treatment and control group, in the meantime, during cholecalciferol supplementation, median 25 (OH) D in patients of the treatment group was increased from 16.2 [ 12.25-19.3] ng/mL to 24.2 [21.05-26.4] ng/mL (p 〈 0.001). Conclusions: the larger part of child population--70.6% has 25 (OH) D concentration 〈 20 ng/mL, cholecalciferol doses used in the study allow eliminating calcidiol deficiency and overcome the boundary of 20 ng/mL, but for normalization of vitamin D status in blood of adolescents residing in Moscow higher dosages shall be used which is to be confirmed by further studies. 展开更多
关键词 School-aged children adolescents vitamin D provision vitamin D insufficiency vitamin D deficiency correction of a low vitamin D status.
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Polytrauma-related deaths in Moscow:Retrospective analysis of 969 autopsy studies
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作者 Gleb Vladimirovich Korobushkin Sergey Vladimirovich Shigeev +2 位作者 Roman Pfeifer Inna Olegovna Chizhikova Alexander Igorevich Zhukov 《Chinese Journal of Traumatology》 2025年第5期319-323,共5页
Purpose Polytrauma is still a challenge for health care organizations.Today,the search for factors to reduce lethality continues.This study aims to describe the causes of death associated with polytrauma in 1 year.Met... Purpose Polytrauma is still a challenge for health care organizations.Today,the search for factors to reduce lethality continues.This study aims to describe the causes of death associated with polytrauma in 1 year.Methods This retrospective study analyzed autopsy data of trauma deaths in Moscow for the whole of 2017.We identified victims with polytrauma,taking into account the Berlin definition as the main inclusion criteria with penetrating and blunt trauma.Each forensic report had information about the pre-hospital and hospital stages of treatment and autopsy data.The exclusion criteria for this study were:isolated injury,forensic reports not related to the examination of entire corpses,and autopsy studies of children(<18 years old).Statistical analysis was performed according to basic principles,including a comparison of groups using the Chi-squared test with Bonferroni comparison test and Fisher's exact test.The critical level of significance(p value)in testing statistical hypotheses in this study was taken as 0.05.Results We analyzed 2337 forensic medical examinations of victims who died of trauma in Moscow in 2017,of which 41.5%(n=969)were polytrauma deaths.Most of the victims(65.4%,n=634)died on the scene,and only 30.0%were admitted to the hospital.The most frequent cause of death was bleeding(72.0%,n=698),followed by traumatic brain injury(43.8%,n=424).They accounted for the first peak(78.4%,p=0.005)of deaths,occurring in the first hours.Then these causes of death in the first peak go down in a few hours,and the second peak of mortality appears in 3–7 days(p=0.001).Conclusions This is the largest full-year autopsy study of polytrauma victims.Our data show that the main cause of polytrauma death is massive bleeding,with a lethality peak in the first hours after injury.The time distribution of polytrauma deaths has a bimodal pattern-the second period of polytrauma deaths occurs in 3–7 days. 展开更多
关键词 POLYTRAUMA Exanguination Damage control Traumadeaths AUTOPSY
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基于BDNF/TrkB通路探讨镇静安神颗粒对乳腺癌相关性失眠小鼠的作用机制
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作者 古春青 郭睿思 +6 位作者 周勤勤 刘恒辉 巴婉玉 孙士玲 王冰 郑玉玲 吴宿慧 《中药新药与临床药理》 北大核心 2026年第1期22-30,共9页
目的基于脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)通路探讨镇静安神颗粒对乳腺癌相关性失眠小鼠的作用机制。方法采用鼠源4T1细胞制备乳腺癌荷瘤小鼠模型,并采用足底电刺激为主的慢性不可预知刺激复制乳腺癌相关性失眠小鼠模型... 目的基于脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)通路探讨镇静安神颗粒对乳腺癌相关性失眠小鼠的作用机制。方法采用鼠源4T1细胞制备乳腺癌荷瘤小鼠模型,并采用足底电刺激为主的慢性不可预知刺激复制乳腺癌相关性失眠小鼠模型。将乳腺癌相关性失眠小鼠随机分为模型组、艾司唑仑组、镇静安神低剂量组、镇静安神高剂量组、镇静安神高剂量+K-252a(BDNF/TrkB通路抑制剂)组,每组12只,另外选取12只乳腺癌荷瘤小鼠作为对照组。艾司唑仑组灌胃给予0.15 mg·kg^(-1)艾司唑仑片;镇静安神低、高剂量组分别灌胃0.54、1.08 g·kg^(-1)镇静安神颗粒;镇静安神高剂量+K-252a组在灌胃1.08 g·kg^(-1)镇静安神颗粒同时,腹腔注射25 mg·kg^(-1)K-252a;每日1次,药物干预持续7 d。观察小鼠一般活动状态;采用戊巴比妥钠翻正实验测定小鼠睡眠质量;旷场实验、高架十字迷宫实验评价小鼠失眠样行为;ELISA法检测小鼠血清5-羟色胺(5-HT)、多巴胺(DA)、γ-氨基丁酸(GABA)含量;RT-qPCR、Western Blot法检测小鼠脑组织中BDNF、TrkB mRNA及蛋白表达水平。结果(1)与对照组比较,模型组小鼠暴躁易激惹,毛发竖起且粗糙、无光泽,昼夜节律消失,体形消瘦,体质量显著降低(P<0.01);睡眠潜伏期显著延长(P<0.01),睡眠时长显著缩短(P<0.01);运动总距离、中心区停留时间、开臂停留时间百分比及进入开臂次数百分比均显著缩短或降低(P<0.01);血清5-HT、GABA含量显著降低(P<0.01),DA含量显著升高(P<0.01);脑组织BDNF、TrkB mRNA及蛋白表达水平显著降低(P<0.01)。(2)与模型组比较,艾司唑仑组及镇静安神低、高剂量组小鼠的一般状态明显改善,体质量显著升高(P<0.01);睡眠潜伏期显著缩短(P<0.01),睡眠时长显著延长(P<0.01);运动总距离、中心区停留时间、开臂停留时间百分比及进入开臂次数百分比均显著延长或提高(P<0.01);血清5-HT、GABA含量显著升高(P<0.01),DA含量显著降低(P<0.01);脑组织BDNF、TrkB mRNA及蛋白表达水平显著升高(P<0.01)。(3)与镇静安神高剂量组比较,镇静安神高剂量+K-252a组小鼠的一般状态变差,体质量显著降低(P<0.01);睡眠潜伏期显著延长(P<0.01),睡眠时长显著缩短(P<0.01);运动总距离、中心区停留时间、开臂停留时间百分比及进入开臂次数百分比均显著缩短或降低(P<0.01);血清5-HT、GABA含量显著降低(P<0.01),DA含量显著升高(P<0.01);脑组织BDNF、TrkB mRNA及蛋白表达水平显著降低(P<0.01)。结论镇静安神颗粒可能通过激活BDNF/TrkB信号通路,调节神经递质水平,改善失眠样行为,提高乳腺癌相关性失眠小鼠的睡眠质量。 展开更多
关键词 乳腺癌 失眠 镇静安神颗粒 BDNF/TrkB信号通路 神经递质 小鼠
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超临界二氧化碳吞吐提高页岩油采收率影响因素研究
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作者 孙琳 孙鸿应 +9 位作者 李一波 于鑫 王志强 陈耀旺 赵杰 何天双 魏兵 蒲万芬 赵金洲 Kadet Valeriy 《油气地质与采收率》 北大核心 2026年第1期48-58,共11页
目前中外油田主要采用二氧化碳吞吐的方法提高页岩油藏的采收率,但在高周期吞吐开发阶段存在边界物性差、区域常规吞吐效果差、动用难度大的问题。超临界二氧化碳(SC-CO_(2))具有黏度低、密度高和溶解性强的特点。为揭示SC-CO_(2)的吞... 目前中外油田主要采用二氧化碳吞吐的方法提高页岩油藏的采收率,但在高周期吞吐开发阶段存在边界物性差、区域常规吞吐效果差、动用难度大的问题。超临界二氧化碳(SC-CO_(2))具有黏度低、密度高和溶解性强的特点。为揭示SC-CO_(2)的吞吐效果,对SC-CO_(2)浸泡处理后的岩心进行CO_(2)吞吐实验,并在此基础上分析了吞吐周期、焖井时间和注入压力对SC-CO_(2)吞吐提高采收率的影响,通过低场核磁共振技术对吞吐前后的页岩进行扫描,研究了页岩基质孔隙中油的分布和动用情况。研究结果表明:①经过SC-CO_(2)浸泡处理后页岩样品的累积采出程度随着吞吐周期的增加而增加,单次采出程度随着吞吐周期的增加而降低,经过浸泡后的岩心渗透率增加了1~2个数量级,孔隙度增大了3~4倍,并且页岩表面更亲CO_(2)。②增加焖井时间能提高SC-CO_(2)吞吐的开发效果,当焖井时间从6 h增加到24 h时,采收率大约提高了10百分点。③页岩累积采出程度和单次采出程度随着注入压力的增加而增加,当注入压力从6 MPa增加到15 MPa时,采收率可提高8~17百分点。④页岩中饱和的油基本都存在于基质中的微孔和中孔中,第一个周期吞吐采出油量最多。 展开更多
关键词 焖井时间 注入压力 油相分布 超临界二氧化碳 页岩油
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强织构p型Bi_(0.5)Sb_(1.5)Te_(3)材料的熔体旋甩快速烧结制备与热电性能研究
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作者 秦逸晗 李珺杰 +7 位作者 樊京辉 李貌 罗婷婷 吴劲松 VLADIMIR Khovaylo 张清杰 苏贤礼 唐新峰 《物理学报》 北大核心 2026年第4期355-365,共11页
传统区熔制备的Bi_(2)Te_(3)基材料力学性能较差,尽管粉末冶金热挤压制备技术有效改善了材料的力学性能,但其包括制粉、烧结、热挤压等工序,工艺流程冗长,严重制约了多晶Bi_(2)Te_(3)基材料的发展及其在微型热电器件的应用.本文采用熔... 传统区熔制备的Bi_(2)Te_(3)基材料力学性能较差,尽管粉末冶金热挤压制备技术有效改善了材料的力学性能,但其包括制粉、烧结、热挤压等工序,工艺流程冗长,严重制约了多晶Bi_(2)Te_(3)基材料的发展及其在微型热电器件的应用.本文采用熔体旋甩方法制备p型Bi_(2)Te_(3)基薄带材料,然后通过直接平铺结合放电等离子活化烧结制备了系列高织构p型Bi_(2)Te_(3)基块体材料.熔体旋甩制备的薄带具有强的织构、丰富纳米结构和缺陷结构,采用不研磨平铺直接快速放电等离子活化烧结有效保留了薄带的取向特征,获得与传统球磨制粉放电等离子活化烧结不一样的沿垂直烧结压力方向强(110)织构特征,743 K烧结样品取向因子与热挤压样品基本相当,(110)面取向因子达到0.37.由于这种强取向特征,样品在平行于压力方向上获得了优异的电传输性能,室温下功率因子达到3.79 m W/(m·K^(2)),此外晶粒细化显著降低了材料的热导率,最终743 K烧结样品在398 K下获得了最高ZT值为1.30,相较于传统区熔样品提升了46%.本文开发出一种快速、便捷的制备策略,用以合成具备强织构、细晶粒特征的高性能Bi_(2)Te_(3)基热电材料,为该类材料在微型热电器件领域的应用奠定了重要基础. 展开更多
关键词 碲化铋 熔体旋甩 织构 放电等离子烧结 缺陷结构
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飞机迎风面蒙皮涂层高动态雨蚀损伤评价和机理
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作者 沙明工 惠志强 +9 位作者 李雨桐 孙莹 李明 魏政 Babaytsev Arseny Fedotenkov Gregory Mednikov Aleksei Tkhabisimov Aleksandr 李玉龙 陈建军 《表面技术》 北大核心 2026年第2期1-14,共14页
目的飞机在雨中高速飞行时,机体迎风面蒙皮涂层受到雨滴冲击作用而产生损伤,出现表面开裂、剥离等典型损伤,会降低结构的安全性和功能性,因此需要对蒙皮涂层的雨蚀损伤机理进行深入研究。方法利用一级轻气炮搭建的单射流试验平台和水切... 目的飞机在雨中高速飞行时,机体迎风面蒙皮涂层受到雨滴冲击作用而产生损伤,出现表面开裂、剥离等典型损伤,会降低结构的安全性和功能性,因此需要对蒙皮涂层的雨蚀损伤机理进行深入研究。方法利用一级轻气炮搭建的单射流试验平台和水切割装置改装的多射流试验平台模拟雨滴冲击。针对以碳纤维T300编制材料为基体,表面涂有3种同等厚度的聚氨酯涂层材料,在不同试验条件下对材料进行雨蚀试验研究。结果在617 m/s冲击速度条件下,以0°、15°、30°的冲击角度以及在15°冲击角度,430、490和555 m/s的冲击速度下对三种涂层材料进行单射流试验;对三种涂层材料在350、370和420 m/s的冲击速度下,进行1000次冲击的多喷射流试验。结果表明:随着冲击角度和速度的变化,三种涂层材料的损伤趋势是一致的;典型损伤形貌相同,即当水锤压力低于涂层材料的屈服强度极限时,损伤区域由环形损伤包围中央未损伤区域构成;当水锤压力超过材料的屈服强度极限时,水锤压力结合侧向射流会造成1~2倍液滴直径的损伤区域。多射流与单射流的试验结果具有相似性。结论通过对比单射流与多射流试验下涂层材料的典型损伤形貌可知,材料的雨蚀损伤机理与自身的力学性能关系密切。根据三种涂层材料在不同试验参数下的损伤结果,材料1性能最佳,在多种试验条件下均有良好的表现,能够满足飞机在不同环境下的飞行需求。 展开更多
关键词 液固冲击 雨蚀损伤 水射流 冲击动力学 复合材料 涂层
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高温日历老化下磷酸铁锂电池安全性能演变规律分析
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作者 吴晓刚 马延阳 +3 位作者 关舒忆 陈宇 Rinat Nasyrov Ramis Bulatov 《天津大学学报(自然科学与工程技术版)》 北大核心 2026年第2期146-154,共9页
磷酸铁锂(LiFePO_(4))电池因其高安全性、长循环寿命和良好的热稳定性,广泛应用于电动车辆和电化学储能系统中.然而,磷酸铁锂电池在长时放置不工作的过程中,面临着日历老化导致其容量衰减和安全性能下降的问题.为了揭示磷酸铁锂电池由... 磷酸铁锂(LiFePO_(4))电池因其高安全性、长循环寿命和良好的热稳定性,广泛应用于电动车辆和电化学储能系统中.然而,磷酸铁锂电池在长时放置不工作的过程中,面临着日历老化导致其容量衰减和安全性能下降的问题.为了揭示磷酸铁锂电池由于长期搁置老化导致的安全性能演变规律,本文开展了高温日历老化下磷酸铁锂电池容量衰减及安全性能的测试及分析,首先,在设计210 d高温搁置加速老化实验的基础上,利用电化学阻抗谱(EIS)结合弛豫时间分布(DRT)处理的方法,对长时高温搁置磷酸铁锂电池的容量衰减机制进行了分析.其次,为了揭示高温搁置下电池安全性能与容量衰减的关系,在电池老化过程的不同阶段开展了热失控行为的测试,同时对不同容量衰减程度的电池电极材料进行了表征分析.测试及分析结果表明,磷酸铁锂电池高温搁置容量衰减的主要表现是电池欧姆阻抗和扩散阻抗显著增加,电池的热失控触发温度(θ_(2))随老化程度的增加略微升高,而热失控最高温度(θ_(3))随老化程度的增加而逐渐下降.电池原位观测显示,正极活性物质的损失是电池高温日历老化条件下安全性能退化的关键因素.研究结果为高温日历老化场景下磷酸铁锂电池容量衰退和安全性能评估提供了一定的参考依据. 展开更多
关键词 磷酸铁锂电池 高温老化 安全性能 容量衰减 热失控
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超临界CO_(2)聚能冲击压裂裂缝起裂与扩展规律
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作者 余星 王海柱 +7 位作者 石明亮 王斌 丁柏昕 张国新 樊旭浩 赵成明 STANCHITS Sergey CHEREMISIN Alexey 《石油勘探与开发》 北大核心 2026年第1期233-244,共12页
针对超临界CO_(2)(SCCO_(2))聚能冲击作用下致密砂岩裂缝的起裂与扩展规律,采用拟三轴SCCO_(2)聚能冲击压裂系统开展室内压裂实验,通过CT扫描和三维裂缝重构揭示聚能压力、孔隙压力和地应力对裂缝特性的影响,结合核磁共振横向弛豫时间... 针对超临界CO_(2)(SCCO_(2))聚能冲击作用下致密砂岩裂缝的起裂与扩展规律,采用拟三轴SCCO_(2)聚能冲击压裂系统开展室内压裂实验,通过CT扫描和三维裂缝重构揭示聚能压力、孔隙压力和地应力对裂缝特性的影响,结合核磁共振横向弛豫时间谱研究SCCO_(2)聚能冲击压裂对砂岩内部损伤的影响。研究显示:与常规水力压裂和SCCO_(2)准静态压裂相比,SCCO_(2)聚能冲击压裂有利于形成多方向起裂和复杂缝网;提高聚能压力可促进层理弱面开启,主裂缝与分支缝交织构成致密缝网;在相同冲击强度下,孔隙压力升高会降低有效法向应力并改变应力波散射路径,诱发更多分支缝,增强裂缝复杂度;地应力差增大促使裂缝沿最大主应力方向扩展、分支减少、形态简化。随着SCCO_(2)聚能压力升高,孔隙体积与连通性总体提升:小—中孔隙以数量增加与连通性增强为主要响应;当聚能压力升高至40~45 MPa时,裂纹贯通并形成较大孔隙与裂隙,对渗流通道与有效储集空间改善起主导作用,最终形成多尺度孔隙-裂缝网络。 展开更多
关键词 超临界CO_(2) 聚能冲击压裂 无水压裂 裂缝起裂 裂缝扩展
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国家一级保护野生植物银缕梅组培快繁体系的建立
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作者 张靓靓 汪贤挺 +4 位作者 陈勇 朱逸凡 卢新元 Zaitseva Svetlana Mikhailovna 杨海芸 《植物学报》 北大核心 2026年第1期114-122,共9页
银缕梅(Parrotia subaequalis)是中国特有的珍稀濒危物种,为国家一级重点保护野生植物。为缓解其濒危现状,以银缕梅带芽茎段为外植体,探究不同消毒方式、基本培养基、植物生长调节剂种类与浓度对其侧芽萌发、增殖和不定根生长的影响,成... 银缕梅(Parrotia subaequalis)是中国特有的珍稀濒危物种,为国家一级重点保护野生植物。为缓解其濒危现状,以银缕梅带芽茎段为外植体,探究不同消毒方式、基本培养基、植物生长调节剂种类与浓度对其侧芽萌发、增殖和不定根生长的影响,成功建立了银缕梅组培快繁体系。结果表明,外植体用75%乙醇消毒后置于0.52%NaClO溶液中浸泡5分钟,接种成活率为83.33%;在基本培养基WPM上侧芽萌芽率最高,为73%;添加KT侧芽萌芽率达91%,但无丛生芽增殖,而添加1.0 mg·L^(–1)TDZ时丛生芽诱导率为48.63%;添加1.5 mg·L^(–1)6-BA和0.003 mg·L^(–1)TDZ组合侧芽增殖效果最好,增殖系数为4.17,芽生长状态良好。银缕梅不定根诱导较困难,高浓度生长素导致芽苗褐化死亡,最佳生根培养基为1/2MS基本培养基中添加0.2 mg·L^(–1)NAA,生根率达60%。该研究建立了银缕梅组培快繁体系,可有效缓解银缕梅濒危现状,为科研和生产提供充足的植物材料。 展开更多
关键词 银缕梅 濒危保护植物 组织培养 丛生芽 增殖
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层合碳纤维复合材料拉胀超结构的力学行为研究
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作者 赵昌方 Boris Nikitovich Fedulov 刘浩 《材料导报》 北大核心 2026年第2期239-248,共10页
碳纤维增强复合材料(CFRP)拉胀超结构凭借其轻质、高强、可设计性等优势,近年来在航空航天领域备受关注。为揭示层合CFRP拉胀超结构的基本力学行为和形成机理,基于经典层合板理论和Euler-Bernoulli梁弯曲理论,分别建立了层合板的二维各... 碳纤维增强复合材料(CFRP)拉胀超结构凭借其轻质、高强、可设计性等优势,近年来在航空航天领域备受关注。为揭示层合CFRP拉胀超结构的基本力学行为和形成机理,基于经典层合板理论和Euler-Bernoulli梁弯曲理论,分别建立了层合板的二维各向异性本构模型和内凹六边形拉胀超结构的等效弹性力学模型,并结合经过验证的有限元方法预测了CFRP元胞的拉伸、压缩和剪切行为。结果表明,面内拉伸和压缩均呈现出线性行为,且拉压刚度相同,但强度因失效位置不同而不同。面内和面外剪切行为均具有非线性,不同方向上的刚度和强度因变形模式、材料性质和失效模式不同而具有明显差异。侧壁的微观失效形貌包括基体开裂、纤维拔出、纤维断裂等,但面外剪切工况下还会出现局部断裂诱发的分层破坏。面内拉压与面外剪切均呈现出负泊松比效应(Y方向拉压时效果更好),且泊松比理论预测结果接近于模拟结果。面外剪切失效应变约为150%,展现出优异的曲面同向性与抗剪切承载能力。这些结果可为复合材料超结构的功能应用和可控设计提供参考。 展开更多
关键词 超材料 超结构 负泊松比 拉胀 复合材料 有限元分析
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