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Relaxation of Mechanical Stress in Poly(vinyl alcohol) Cryogels of Different Compositions

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Chinese Journal of Polymer Science 2023年第3期41卷 442-447,I0010页

作者： vladimir n.Manzhai Maria S.Fufaeva Ekaterina S.Kashlach Institute of Petroleum Chemistry of the Siberian Branch of the Russian Academy of Sciences Tomsk 634055Russia

The study presents the experimental results of measurements of the relaxation time of cryogels formed from various colloid-dispersed systems based on a poly(vinyl alcohol) aqueous *** is shown that the value of relaxation time,which characterizes the relationship between the viscosity and elasticity of real bodies,describes the rheological properties of materials more objectively than the traditional assessment of their physical and mechanical characteristics only by the elasticity modulus of the samples.

关键词： Cryogel Relaxation processes Viscoelasticity Rheological properties

树轮记录的阿尔泰山南坡过去304年夏季温度变化及水热配置模式

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第四纪研究 2024年第4期44卷 859-868页

作者：李强刘禹 Olga Solomina 王嘉川 vladimir Matskovsky 宋慧明孙长峰庞文轩闫亚兰蔡秋芳任萌程海全球环境变化研究院西安交通大学陕西西安710049 黄土与第四纪地质国家重点实验室中国科学院地球环境研究所陕西西安710061 Institute of Geography Russian Academy of SciencesMoscow 119017Russia 西安地球环境创新研究院陕西西安710061

阿尔泰山南坡受到西风急流、北冰洋冷湿气流、蒙古-西伯利亚高压和亚洲低压共同影响,形成了当地特有的气候模式;同时,阿尔泰山地区是欧亚沟通的枢纽地带,气候变化对周边人类生产生活以及生态系统影响显著。因此有必要了解阿尔泰山周边... 详细信息

阿尔泰山南坡受到西风急流、北冰洋冷湿气流、蒙古-西伯利亚高压和亚洲低压共同影响,形成了当地特有的气候模式;同时,阿尔泰山地区是欧亚沟通的枢纽地带,气候变化对周边人类生产生活以及生态系统影响显著。因此有必要了解阿尔泰山周边气候变化长期历史,识别气候变化特征,总结规律以应对未来气候变化带来的灾害。本研究利用相关分析发现阿尔泰山南坡西伯利亚落叶松树轮宽度年表与夏季(6~7月)温度呈显著关系(r=0.626,n=58,p<0.001),进而建立一阶线性回归模型方程定量重建了阿尔泰山南坡过去304年(1715~2018年)夏季温度变化。统计结果显示重建序列稳定可靠,并有能力代表大范围的温度变化特征。重建存在5个暖期(1740~1767年、1775~1793年、1837~1847年、1898~1909年、1990~2018年)和5个冷期(1715~1727年、1807~1828年、1848~1858年、1876~1897年、1927~1940年)。虽然自1990年来温度持续上升(1990~2018年温度距平0.33℃),但并未超过1740~1767年的温度(温度距平0.49℃)。结合周边降水重建序列,发现研究区域在过去3个多世纪表现出夏季水热同步的配置模式,即暖湿/冷干模态占主导地位。

关键词：温度重建树轮宽度阿尔泰山西伯利亚落叶松

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Unveiling the nature of Polar-ring Galaxies from Deep Imaging

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Research in Astronomy and Astrophysics 2022年第11期22卷 34-50页

作者： Aleksandr V.Mosenkov vladimir P.Reshetnikov Maria n.Skryabina Zacory Shakespear Department of Physics and Astronomy N283 ESCBrigham Young UniversityProvoUT 84602USA Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye Chaussee 65/1196140 St.PetersburgRussia St.Petersburg State University 7/9 Universitetskaya Nab.199034 St.PetersburgRussia

General structural properties and low surface brightness tidal features hold important clues to the formation of *** this paper,we study a sample of polar-ring galaxies(PRGs)based on optical imaging from the Sloan Digital Sky Survey Stripe 82 and other deep *** investigate the deepest images of candidates for PRGs to *** carry out photometric decomposition on the host galaxies and associated polar structures that allows us to derive the structural properties of both *** are able to detect very faint tidal structures around most PRGs in our *** several galaxies,we can directly observe the formation of the polar ring due to merging,which is manifested in debris of the victim galaxy and an arc-like polar structure made up of its *** a few cases,we can discern signs of tidal *** results obtained indicate that the gravitational interaction and merging of galaxies are the most plausible mechanisms for the formation of PRGs.

关键词： data analysis techniques:photometric galaxies:structure

H_3PW_(12)O_(40)/CnTs吸附-分解nO_x及微波作用效果

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高等学校化学学报 2012年第8期33卷 1826-1834页

作者：张学杨程琳杨烽王睿 korchak vladimir 山东大学环境科学与工程学院济南250100 山东大学化学化工学院济南250100 北京大学化学与分子工程学院北京100871 俄罗斯科学院西蒙诺夫化学物理研究所多相催化实验室莫斯科119991

将碳纳米管(CnTs)载体分别经混酸与硝酸蒸气预处理并在不同温度下煅烧,然后分别采用浸渍法及机械研磨法负载磷钨酸(HPW),制备出HPW/CnTs催化剂,对比考察了上述催化剂对nOx的吸附与分解效果.在空速为10000 h-1、吸附温度为200℃的条件下,... 详细信息

将碳纳米管(CnTs)载体分别经混酸与硝酸蒸气预处理并在不同温度下煅烧,然后分别采用浸渍法及机械研磨法负载磷钨酸(HPW),制备出HPW/CnTs催化剂,对比考察了上述催化剂对nOx的吸附与分解效果.在空速为10000 h-1、吸附温度为200℃的条件下,用0.5 g催化剂对1696 mg/m3的nOx进行吸附实验,结果表明,以硝酸蒸气预处理且经300℃煅烧后的CnTs为载体,采用机械研磨负载法制备的催化剂HPW/CnTs对nOx的吸附率与吸附能力最高,分别为54%与16.6 mg nOx/(g.h).对吸附nOx后的催化剂体系进行了催化分解nOx的程序升温脱附-质谱(TPD-MS)研究,结果表明,所吸附的nOx在快速升温过程中发生分解,在此过程中有氧产生,分解产物包括n2,O2及n2O.采用电阻炉快速加热与微波辐射2种方式分别对吸附的nOx进行催化分解,结果表明,微波功率为700 W时,nOx分解为n2的收率为33.3%,高于电阻炉以150℃/min快速升温的n2收率.使用过的催化剂通水蒸气后可实现再生,对再生后的催化剂进行循环使用研究,结果表明,再生后的催化剂吸附与催化分解nOx的性能未有明显下降.

关键词：氮氧化物磷钨酸碳纳米管微波辐射吸附-分解

Rare earth elements(REE)and isotope composition(δ^(13)C andδ^(18)O)of manganese ores of Chiatura deposit(Georgia):features of ore formation and genesis

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Acta Geochimica 2023年第4期42卷 779-801页

作者： vladimir n.Kuleshov Andrey Yu.Bychkov Irina Yu.nikolaeva Maria E.Tarnopolskaya Geological Institute Russian Academy of SciencesPyzhevskii Per.7MoscowRussia 119017 Lomonosov Moscow State University Leninskie Gory1MoscowRussia 119899

The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were *** of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(Eu/Eu*_(PAAS))*** oolitic manganese ores were formed in oxic shallow marine *** content and distribution of REEs(in particular Ce and Eu)in these ores are connected mainly with ferrous *** performed C-and O-isotope research in Mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)*** negative cerium anomalies in the studied carbonate ores reflect the specific REE patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's *** deficiency of cerium in this zone remains debatable and requires further *** of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and *** absence of europium anomaly indicates about lack of hydrothermal solution input.

关键词： REE Cerium anomaly Carbon and oxygen isotope geochemistry Oxide and carbonate manganese ores Chiatura deposit

Ecology and social behavior of the social vole Microtus socialis: A generalized review

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Current Zoology 2023年第6期69卷 775-783页

作者： vladimir S.Gromov A.n.Severtsov Institute of Ecology and Evolution Leninsky prosp.33Moscow 119071Russia

The present review is a compilation of the published data on the ecology and social behavior of the social *** studies provide evidence that these voles live in family groups consisting of 1 adult male,1 or 2 breeding females,and their offspring(1 or 2 litters).The social vole is capable of year-round reproduction,but in arid regions,the voles demonstrate seasonality in *** mating system of this species may be defined as behavioral monogamy.A typical feature of the space use system is territoriality characterized by a locus-dependent dominance in relationships between neighboring breeding pairs as well as family *** family group social organization may be defined as consistent relationships without a dominant *** voles are cooperative in defending their territories,constructing burrows,digging underground tunnels,maintaining nests,and raising *** appears to enhance the survival of family groups of this species under the extreme climaticconditionsof Central Asia.

关键词： ecology family-group lifestyle mating system reproduction social organization social vole

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阿兰都城蔑怯思与蒙古征战考

西域研究 2024年第1期 110-126页

作者：弗拉其米尔·费奥多罗维奇·米诺尔斯基芮传明上海社会科学院历史研究所

13世纪,蒙古人对欧亚草原地区和东欧进行了所谓的“西征”。本文周密地考证了被蒙古军摧毁的阿兰人/阿速人(即奥赛梯人)的都城蔑怯思的方位。其主要资料来自志费尼和拉施德丁的相关记载,同时也包括其他中世纪史家的著述。本文不仅得出... 详细信息

13世纪,蒙古人对欧亚草原地区和东欧进行了所谓的“西征”。本文周密地考证了被蒙古军摧毁的阿兰人/阿速人(即奥赛梯人)的都城蔑怯思的方位。其主要资料来自志费尼和拉施德丁的相关记载,同时也包括其他中世纪史家的著述。本文不仅得出了“蔑怯思位于高加索山北麓主水道捷列克河之支流松佳河畔”的推论,而且还对志费尼、拉施德丁有关蒙古西征的史料作了详细考释,从而为“草原丝路”的研究提供了有价值的参考资料。

关键词：志费尼拉施德丁蒙古西征蔑怯思高加索山

Pediatric GnAO1 encephalopathies:from molecular etiology of the disease to drug discovery

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neural Regeneration Research 2023年第10期18卷 2188-2189页

作者： vladimir L.Katanaev Jana Valnohova Denis n.Silachev Yonika A.Larasati Alexey Koval Translational Research Centre in Oncohaematology Department of Cell Physiology and MetabolismFaculty of MedicineUniversity of GenevaGenevaSwitzerland Institute of Life Sciences and Biomedicine Far Eastern Federal UniversityVladivostokRussia Department of Functional Biochemistry of Biopolymers A.N.Belozersky Research Institute of Physico-Chemical BiologyMoscow State UniversityMoscowRussia

Gao is the major G protein in neurons,where it transduces signals from numerous G proteincoupled receptors(GPCRs)such as D2 dopamine,μ-opioid,M2 muscarinic,or α2-adrenergic *** 2013,the first mutations in GnAO1,the gene encoding Gao,were described in pediatric patients with encephalopathies(nakamura et al.,2013),suffering from movementdisorders,epileptic seizures。

关键词： encephalo opioid

Synthesis of spherical Y_(2)O_(3):Er emitting particles with variable radial composition by controlled double-jet precipitation of layered precursors

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Particuology 2023年第3期74卷 92-102页

作者： Danil K.Aleshin Maxim A.Mashkovtsev Anastasiya S.Kosykh Yulia A.Kuznetsova Anatoly F.Zatsepin vladimir n.Rychkov Institute of Physics and Technology Ural Federal University19 Mira Str.620002YekaterinburgRussia

Spherical(Y_(0.98)Er_(0.02))_(2)(OH)_(5)(nO_(3))·xH_(2)O particles were synthesized by controlled double-jet precipitation,with a“core”of pure layered yttrium hydroxide nitrate,and a“shell”of co-precipitated yttrium-erbium layered hydroxide *** an increase in precipitation pH from 7 to 9.5,the size of layered“building units”decreases and the architecture of their assemblies changes from flower-like through network-like spherical to irregular *** there,spherical particles gradually increase their diameter due to the continuous uniform growth of curved layered sheets on their *** was established that such growth behavior and network-like architecture of spherical particles was retained even when yttrium was replaced by erbium ions in the layered host lattice during the formation of an Er-enriched“shell”.Analysis of SEM,EDS,XPS,photoluminescence spectra and concentration quenching effects of heat-treated Y_(2)O_(3):Er(2 at.%)particles indicate that the radial distribution of erbium in particles is most controllable in a narrow pH range of co-precipitation of layered precursors(pH8).Вy widely varying the elemental composition of“building units”during co-precipitation,one can simultaneously finely control the composition of layered hydroxides in the radial direction of the spherical particles and grow multicomponent“multi-shell”powders with desired properties.

关键词： Layered hydroxides Erbium Controlled precipitation Emitting particles Photoluminescence Concentration quenching