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Elevation of the Power Factor of Co4Sb12 Skutterudite with Sm-Doping in High-Pressure High-Temperature Synthesis

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Chinese Physics Letters 2010年第6期27卷 237-239页

作者： jiaNG Yi-Ping jia xiao-peng GUO Wei XU Hui-Wen DENG Le ZHENG Shi-Zhao MA Hong-An National Lab of Superhard Materials Jinlin University Changchun 130012 Department of Physics Beihua University Jilin 132013

A thermoelectric material Smx Co4Sb12 （0（ x ≤1.0） is synthesized at high pressure and high temperature leading to an enhanced power factor. The experimental measurements show that the SmxCo4Sb12 compounds exhibits n-type conduction. The absolute value of the Seebeck coefficient decreases with increasing Sm fraction. The resistivity increases with samarium content x from 0.1 to 0.2, but decreases dramatically when x changes from 0.2 to 1.0. The maximum power factor reaches 13.1 μ***^-1K-2 at x =1.0, which is larger than the data previously reported for the La-doped CoSb3 prepared at room pressure.

关键词： Pressure Energy sources Measurement

Synthesis and Magnetotransport Properties of CrO_(2)-TiO_(2) Composites

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Chinese Physics Letters 2013年第3期30卷 154-157页

作者： FAN Yin-Bo ZHANG Cai-Ping DU xiao-Bo WEN Ge-Hui MA Hong-An jia xiao-peng State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012 College of Physics Jilin UniversityChangchun 130012

CrO_(2)-TiO_(2) composites are synthesized by using a high temperature and high pressure method using CrO_(3) and H_(2)TiO_(3) as *** composites consist of large rod-like CrO_(2) crystals separated by small TiO_(2) *** CrO_(2) in the composites is very pure and its saturation magnetization is very close to the theoretical value(i.e.,2μ_(B) per formula unit).The composites exhibit a large negative magnetoresistance(MR)at 5 *** MR in CrO_(2)-TiO_(2) composites is mainly attributed to spin-polarized tunneling between CrO_(2) *** conductivity of the composites is best described by a fluctuation-induced tunneling model below 230 K.

关键词： composites CrO2 tunneling

Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： jia-jia Wu Fei Wang peng-Qi Wan Li Pan Chun-Sheng xiao Zhe Ma Yue-Sheng Li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Reaction Mechanism of Al and N in Diamond Growth from a FeNiCo-C System

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Chinese Physics Letters 2011年第6期28卷 315-317页

作者： LI Shang-Sheng LI xiao-Lei MA Hong-An SU Tai-Chao xiao Hong-Yu HUANG Guo-Feng LI Yong ZHANG Yi-Shun jia xiao-peng School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454003 State Key Lab of Superhard Materials Jilin UniversityChangchun 130012 Luoyang Institute of Science and Technology Luoyang 471023

It is significant to investigate the action of nitrogen getters,which are used to synthesize type-IIa large diamond single crystals under high pressure and high temperature(HPHT).The reaction mechanism of Al as a nitrogen getter and N in the HPHT alloy solvent is still indeterminate at *** order to investigate the reaction of Al and N in the HPHT alloy solvent,Al and AlN are respectively added to the system of Fe55Ni29Co16−C(wt%,***-C)for the synthesis of diamonds at about 5.5 GPa and 1600 *** concentration of nitrogen in the diamonds is characterized by a micro Fourier transform infrared(micro-FTIR)*** experimental results show that cN decreases when Al is added to the FeNiCo-C ***,it increases when AlN is added.A reversible reaction confirms that Al and N can react and form AlN,simultaneously AlN can be decomposed into Al and N in the HPHT alloy *** the mechanism of eliminating the nitrogen of nitrogen getter Al is realized in detail.

关键词： alloy FeNiCo mechanism

Subchronic Toxicity Study on Soy Isoflavones in Rats

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Biomedical and Environmental Sciences 2009年第3期22卷 259-264页

作者： WEN-ZHONG ZHANG WEN-MING CUI XIN ZHANG WEI WANG XU-DONG jia xiao-peng ZHANG NING LI Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100021 China

Objective To investigate the subchronic toxicity of soy isoflavones （SIF） in male rats. Method Fifty Sprague-Dawley rats were randomly divided into 5 groups, 10 rats per group. SIF were given to rats in different groups by gavage at dose of 0, 0.2, 0.5, 1.5, and 4.5 g/kg bw, respectively for 13 weeks. Clinical manifestations, body weight, and food consumption were observed weekly. At the end of the study, urinalysis, hematology, clinical chemistry, total testosterone, and follicle-stimulating hormone were tested, and histopathological examinations were performed. Results No mortality, ophthalmic abnormalities or treatment-related clinical signs were identified during the study. As compared with the control group, significantly lower body weights and food consumption were observed in 1.5 and 4.5 g/kg bw groups. In clinical chemistry tests, triglyceride was significantly decreased and high-density lipoprotein cholesterol was significantly increased in all SIF-treated groups. Total testosterone levels were significantly lower in 0.50, 1.50, and 4.5 g/kg bw dose groups than in the control group. Microscopic examination showed that the mammary glands exhibited hyperplasia and excreted latex in rats of the 4.5 g/kg bw group. No changes attributable to treatment of SIF in other parameters were found. Conclusion SIF at high dosages caused significant endocrine disruption in male rats. The no observed adverse effect level （NOAEL） of SIF to male rats in this study is considered to be 0.20 g/kg bw.

关键词： Soy isoflavone Rat Subchronic toxicity

Transformation of Nitrogen State in High-Level N-Doped Gem-Quality Diamond Crystal Annealed at High Temperature and High Pressure

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Chinese Physics Letters 2012年第10期29卷 151-154页

作者： HUANG Guo-Feng jia xiao-peng MA Hong-An BAI Hong-Bo YIN Ji-Wen HU Yi-Ga Department of Physics and Electronic Information Engineering Chifeng CollegeChifeng 024000 National Lab of Superhard Materials Jilin UniversityChangchun 130012

The colourless IaA-type gem-quality diamond crystals containing a high concentration of nitrogen(1500–1700 ppm)were successfully prepared by annealing the as-grown Ib-type N-doped diamonds at a high temperature and high pressure in China-type cubic anvil high-pressure *** were carried out at pressures of 6.5–7.0 GPa and temperatures from 1900 K to 2100 *** treatment on high-level N-doped diamond crystals shows that the colour of the diamond crystals is obviously reduced from green to colourless after annealing treatment within 1 h at a higher temperature,which is induced by nitrogen aggregation in the diamond lattice indicated by infrared(IR)*** is further revealed that active energy of the nitrogen atom transforming from the dispersed form to the aggregated form is much lower than that in the standard Ib-type diamond crystals with nitrogen concentration less than 300 *** colourless IaA-type diamond crystal prepared by annealing at 2100 K displays the same properties in IR spectra as the high-quality natural diamonds which are classified into the IaA type.

关键词： annealing treatment Transformation

An Effective Solution for the Best Set of Beveling Parameters of the Cubic High-Pressure Tungsten Carbide Anvil

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Chinese Physics Letters 2012年第11期29卷 162-164页

作者： HAN Qi-Gang ZHANG Qiang LI Ming-Zhe jia xiao-peng LI Yue-Fen MA Hong-An Roll-forging Research Institute Jilin UniversityChangchun 130025 National Lab of Superhard Materials Jilin UniversityChangchun 130012 College of Earth Sciences Jilin UniversityChangchun 130061

Determining the best set of beveling parameters is an advantageous characteristic of the geometrical conditions for a cubic high-pressure tungsten carbide(WC)anvil,but it is almost impossible to deduce experimentally(much affected by defects in the material).In order to remove the affection of defects in materials,we investigate computational stress analyses in different beveling parameters of WC anvils by the finite element *** results indicate that the rate of cell pressure transmitting and failure crack in the WC anvil monotonically increases with the bevel angle from 42°to 45°.Furthermore,there are two groups of actual users of beveled anvils,one group preferring 41.5°,which can decrease the rate of failure crack in WC anvil,the other group preferring 42°,which can increase the rate of cell pressure *** work would give an effective solution to solve the problem of the design of a cubic high-pressure WC anvil experimentally and will greatly help to improve the cubic high-pressure WC anvil type high pressure techniques.

关键词： crack carbide cubic

A Bregman-Style Improved ADMM and its Linearized Version in the Nonconvex Setting:Convergence and Rate Analyses

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Journal of the Operations Research Society of China 2024年第2期12卷 298-340页

作者： peng-Jie Liu Jin-Bao jian Hu Shao xiao-Quan Wang jia-Wei Xu xiao-Yu Wu School of Mathematics Jiangsu Center for Applied MathematicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006GuangxiChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

This work explores a family of two-block nonconvex optimization problems subject to linear *** first introduce a simple but universal Bregman-style improved alternating direction method of multipliers(ADMM)based on the iteration framework of ADMM and the Bregman ***,we utilize the smooth performance of one of the components to develop a linearized version of *** to the traditional ADMM,both proposed methods integrate a convex combination strategy into the multiplier update *** each proposed method,we demonstrate the convergence of the entire iteration sequence to a unique critical point of the augmented Lagrangian function utilizing the powerful Kurdyka–Łojasiewicz property,and we also derive convergence rates for both the sequence of merit function values and the iteration ***,some numerical results show that the proposed methods are effective and encouraging for the Lasso model.

关键词： Nonconvex optimization Alternating direction method of multipliers Kurdyka-Lojasiewicz property Convergence rate

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen Sheng-He Wu Rui-Feng Wang jia-jia Zhang peng-Fei Xie Min Wang xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine ***,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine *** this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East *** characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic *** find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single *** the topography is irregular and presents topographic lows,lobe complexes first infill these *** lobes are deposited preferentially at positions with higher longitudinal(***-slope)slope *** the longitudinal slope becomes higher,the aspect ratio of the single lobes ***(***-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single *** the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap ***,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,*** tend to accumulate *** results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean