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Chinese Journal of Structural Chemistry 2006年第7期25卷 878-882页

作者： li Wei li Chang-Hong yANG ying-Qun CHEN Zhi-Min KUANG Dai-Zhi ZHANG Chun-Hua KANG yun-Fei Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China Department of Chemical Engineering Hunan Institute of Technology Hengyang 421008 China

A one-dimensional chain cobalt（Ⅱ） coordination polymer with 2,4,6-trimethyl- benzoic acid, 4,4′-bipyridine and cobalt perchlorate anhydrous has been synthesized and characterized in the mixture solvent of water and alcohol. Crystal data for this complex： monoclinic, space group C2/c, a = 2.3805（8）, b = 1.1464（4）, c = 1.5807（5） nm, y = 128.435（4）°, V= 3.3791（18） nm^3, Dc = 1.246 g/cm^3, Z = 4, F（000） = 1340, final GooF = 1.009, R = 0.0504 and wR = 0.1287. Structural analysis shows that the cobalt ion is coordinated with two nitrogen atoms of one 4,4′- bipyridine molecule and four oxygen atoms from two 2,4,6-trimethylbenzoic acid molecules and two alcohol molecules, giving a distorted octahedral coordination geometry. The result of TG analysis indicates that the title complex is stable till 200 ℃.

关键词： cobalt(Ⅱ) complex crystal structure thermal stability analysis

Criterions for identifying H-tensors

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Frontiers of Mathematics in China 2016年第3期11卷 661-678页

作者： Ruijuan ZHAO Lei GAO Qilong liU yaotang li School of Information Engineering Lanzhou University of Finance and Economics Lanzhou 730020 China School of Mathematics and Statistics Yunnan University Kunming 650091 China Institute of Mathematics and Information Science Baoji University of Arts and Sciences Baoji 721013 China

Some new criteria for identifying H-tensors are obtained. As applications, some sufficient conditions of the positive definiteness for an even- order real symmetric tensor are given, as well as a new eigenvalue inclusion region for tensors is established. It is proved that the new eigenvalue inclusion region is tighter than that of y. yang and Q. yang [SIAM J. Matrix Anal. Appl., 2010, 31： 2517-2530]. Numerical examples are reported to demonstrate the corresponding results.

关键词： H-Tensor real symmetric tensor positive definite eigenvalueinclusion set

雅鲁藏布江中游拉萨裸裂尻鱼环境DNA检测及生物量评估

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水生态学杂志 2024年第2期45卷 84-91页

作者：李冰冯秀朱仁隋晓云贾银涛陈毅峰中国科学院水生生物研究所湖北武汉430072 中国科学院大学北京100049

建立快速和准确的环境DNA(eDNA)检测方法,可为鱼类的长期监测提供便利,为鱼类资源保护和管理提供技术支撑。2019年在雅鲁藏布江中游干流及拉鲁湿地和茶巴朗湿地采集了20种鱼和水样,针对拉萨裸裂尻鱼(Schizopygopsis younghusbandi young... 详细信息

建立快速和准确的环境DNA(eDNA)检测方法,可为鱼类的长期监测提供便利,为鱼类资源保护和管理提供技术支撑。2019年在雅鲁藏布江中游干流及拉鲁湿地和茶巴朗湿地采集了20种鱼和水样,针对拉萨裸裂尻鱼(Schizopygopsis younghusbandi younghusbandi)设计Cytb基因的特异性引物和探针,利用微滴式数字PCR(ddPCR)检测水样中e DNA拷贝数,并分析其与生物量和丰度之间的相关性。结果显示,正反向引物及探针序列与其他19种鱼之间的平均错配碱基数分别为6.8、6.9和3.6,且对其基因组DNA进行ddPCR扩增没有荧光信号。通过对比ddPCR和网捕2种方法,70%样点中检测结果相同,剩余30%样点都是网捕未捕获但ddPCR检出的情况。在拉鲁湿地和雅鲁藏布江干流的样点中,水样eDNA拷贝数与拉萨裸裂尻鱼生物量和丰度之间均具有显著的相关性,拉鲁湿地水样e DNA与二者的相关系数分别为0.987和0.647,雅鲁藏布江水样eDNA与二者的相关系数分别为0.786和0.756,表明eDNA技术是鱼类分布和生物量监测的有效方法。eDNA检测易受到近缘物种和水体理化性质的影响。

关键词：环境DNA 微滴式数字PCR 拉萨裸裂尻鱼物种检测雅鲁藏布江中游

Synthesis of Ultraviolet Absorption Polylactide via Immortal Polymerization of rac-Lactide Initiated by a Salan-yttrium Catalyst

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Chinese Journal of Polymer Science 2018年第2期36卷 202-206页

作者： Wei Zhao Chuan-yang li Chun-Ji Wu Xin-li liu Ze-Huai Mou Chang-Guang yao Dong-Mei Cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Changchun BranchChangchun 130022China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi'an 710021China

A highly efficient strategy for the synthesis of polylactide with the UV absorption ability was established by employing a Salan-yttrium complex（acting as a fast runing catalyst） combined with large excess hydroxyl functionalized benzophenone, BP′-OH. During polymerization, BP′-OH, acting as the chain transfer agent, attached to the active rare-earth metal catalyst via a rapid-reversible exchange reaction to initiate the polymerization. Thus, more polyester chains appeared to grow from one active metal species, and the UV absorption fragments were incorporated into the polymer chains at specific sites, in situ. A high productivity up to 1000 mol LA/mol（Salan-y） was successfully achieved and 100 BP′-labeled PLA chains grew from each active metal center.

关键词： yttrium catalyst Ring-opening polymerization Polylactide Ultraviolet absorption

Unexpected Grob-type fragmentation of vinylogous β-silyloxy-cyclobutanone into γ-lactone

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Chinese Chemical Letters 2017年第5期28卷 968-970页

作者： Xiang Wu Wei-Dong Z.li School of Chemistry and Chemical Engineering Hefei University of Technology Innovative Drug Research Centre Chongqing University

An unusual formal oxy transposition of vinylogous β-silyloxy-cyclobutanone 1（a 1,5-difunctionalized substrate） under mild acidic conditions（aqueous HF in CH3CN at 0℃） to the decalinic y-lactone 2 was described.A... 详细信息

关键词： Grob fragmentation Vinylogous β-silyloxy-cyclobutanone Decalinic γ-lactone Oxy transposition Intramolecular γ-lactonization

Pairing and Quantum Double of Finite Hopf C~*-Algebras

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1121-1128页

作者： Ming liU li Ning JIANG Guo Sheng ZHANG Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China

This paper defines a pairing of two finite Hopf C^＊-algebras A and B, and investigates the interactions between them. If the pairing is non-degenerate, then the quantum double construction is given. This construction yields a new finite Hopf C^＊-algebra D（A, B）. The canonical embedding maps of A and B into the double are both isometric.

关键词： Hopf C^*-algebra pairing quantum double GNS representation

Mathematical Modeling and Simulation of Antibubble Dynamics

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Numerical Mathematics(Theory,Methods and Applications) 2020年第1期13卷 81-98页

作者： Junxiang yang yibao li Darae Jeong Junseok Kim Department of Mathematics Korea UniversitySeoul 02841Republic of Korea School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China Department of Mathematics Kangwon National UniversityGangwon-do 24341Republic of Korea

In this study,we propose a mathematical model and perform numerical simulations for the antibubble *** antibubble is a droplet of liquid sur-rounded by a thin film of a lighter liquid,which is also in a heavier surrounding *** model is based on a phase-field method using a conservative Allen–Cahn equa-tion with a space-time dependent Lagrange multiplier and a modified Navier–Stokes *** this model,the inner fluid,middle fluid and outer fluid locate in specific diffusive layer regions according to specific phase filed(order parameter)*** we represent the antibubble with conventional binary or ternary phase-field models,then it is difficult to have stable thin ***,the proposed approach can prevent nonphysical breakup of fluid film during the *** numerical tests are performed to verify the efficiency of the proposed model.

关键词： Antibubble conservative Allen-Cahn equation Navier-Stokes equation

Geology,Geochemistry and Zircon U-Pb Geochronology of Porphyries in the Dabate Mo-Cu Deposit,Western Tianshan,China:Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 530-544页

作者： DUAN Shigang ZHANG Zuoheng WANG Dachuan li Fengming MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China School of Earth Science and Resources China University of GeoscienceBeijing 100083China Xinjiang Bureau of Geology and Mineral Resources Urumqi 830000China

The Dabate Mo-Cu deposit is a medium-sized porphyry-type deposit in the Sailimu Lake region, western Tianshan, China. We present the geology, geochemistry and zircon U-Pb geochronology of granite porphyries from the Dabate district with the intent to constrain their tectonic setting and petrogenesis. Porphyries in the Dabate district include granite porphyry I（gray white color with large phenocrysts）, granite porphyry II（pink color with small phenocrysts） and quartz porphyry. Granite porphyry II is the Cu and Mo ore-bearing granitoid in the Dabate deposit. LA-ICPMS zircon U-Pb analyses indicate that granite porphyry II was emplaced at 284.2±1.8 Ma. Granite porphyry I and II have similar geochemical features and are both highly fractionated granites：（1） They have high SiO2 content（70.93–80.18 wt% and 72.14–72.64 wt%, respectively）, total alkali（7.58–8.95 wt% and 9.35–9.68 wt%, respectively）, mafic index（0.95–0.98 and 0.93–0.94, respectively） and felsic index（0.79–0.94 and 0.89–0.91, respectively）;（2） They are characterized by pronounced negative Eu anomaly, ＂seagullstyle＂ chondrite-normalized REE patterns and ＂tetrad effect＂ of REE;（3） They are rich in Rb, K, Th, Ta, Zr, Hf, y and REE, but depleted in Sr, P, Ti and Nb. The magma of granite porphyries in Dabate can be interpreted to have been generated by partial melting of the upper crust due to mantle-derived magma underplating in a post-collisional extensional setting.

关键词： porphyry Cu-Mo deposit post-collisional extension zircon U-Pb age petrogenesis Dabate Tianshan Proto-Tethys

Microstructure and texture evolution of Mg–7y–1Nd–0.5Zr alloy sheets with different rolling temperatures

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Rare Metals 2020年第11期39卷 1273-1278页

作者： Jing-Bao liu Kui Zhang Jing-Tao Han Xing-Gang li yong-Jun li Ming-Long Ma Jia-Wei yuan Guo-liang Shi State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing100088China School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The extruded Mg-7y-1Nd-0.5Zr(wt%)alloy were performed to the same strain hot rolling with different *** microstructure and texture evolution of the sheets were investigated by optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and electron back-scattered diffraction(EBSD).The results indicate that the microstructure becomes homogeneous after hot rolling process and precipitated phase distributes at grain boundaries along rolling *** the increase in rolling temperature,the grains of sheet grow *** sheet rolling at 400℃is composed of recrystallization grains,the necklace of the precipitated phase in the grain boundaries and excessive *** structure of necklace of the precipitated phase is fcc structure with lattice constant of a=0.75 *** rolling temperatures increasing from 400 to 450℃,the content of recrystallized grains in volume fraction with relatively random orientations increases *** with the rolling process at 400℃,the amount of precipitated phases is reduced at the grain boundary,and the precipitated phase begins to appear in the grain interior when rolling at 450℃.The structure of the precipitated phase is fcc with lattice constant of a=2.22 *** recrystallization grains begin to grow in the rolling process at 500℃.The basal texture is obviously produced during the rolling process at 400 and 450℃;however,the basal texture is weak in the rolling process at 500℃.

关键词： Rare earth magnesium alloy Rolling Texture Precipitated phase

Bacterial and archaeal community structure of pan-Arctic Ocean sediments revealed by pyrosequencing

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Acta Oceanologica Sinica 2017年第8期36卷 146-152页

作者： liN Xuezheng ZHANG liang liU yanguang li yang The First Institute of Oceanography State Oceanic AdministrationQingdao 266061China

This study was to investigate bacterial and archaeal community structure of pan-Arctic Ocean sediments by pyrosequencing. In total, investigation of three marine sediments revealed 15 002 bacterial and 4 362 archaeal operational taxonomic units （OTUs） at the 97% similarity level. Analysis of community structure indicated that these three samples had high bacterial and archaeal diversity. The most relatively abundant bacterial group in Samples CC 1 and R05 was Proteobacteria, while Firmicutes was dominant in Sample BL03. Thaumarchaeota was the most relatively abundant archaeal phylum in Samples CC1 and R05, and the relative abundance of Thaumarchaeota was almost as high as that of Euryarchaeota in Sample BL03. These two phyla accounted for nearly 100% of the archaeal OTUs. 6-Proteobacteria and y-Proteobacteria were the two most relatively abundant classes at Proteobacterial class level, and their relative abundance was more than 60% in Samples CC1 and R05. There were also differences in the top 10 relatively abundant bacterial and archaeal OTUs among the three samples at the 97% similarity, and only 12 core bacterial OTUs were detected. Overall, this study indicated that there were distinct microbial communities and many unique OTUs in these three samples.

关键词： Arctic sediment microbial community diversity pyrosequencing