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chinese Physics B 2020年第8期29卷 108-114页

作者： y y wu X L Zhu H y yang Z G Wang y H Li B T Wang School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science center Dongguan 523808China School of Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China collaborative Innovation center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Sulfide nanocrystals and their composites have shown great potential in the thermoelectric(TE)field due to their extremely low thermal *** a solid and hollow metastable Au2S nanocrystalline has been successfully ***,we study the TE properties of this bulk Au2S by first-principles calculations and semiclassical Boltzmann transport theory,which provides the basis for its further experimental *** results indicate that the highly twofold degeneracy of the bands appears at theΓpoint in the Brillouin zone,resulting in a high Seebeck ***,Au2S exhibits an ultra-low lattice thermal conductivity(~0.88 W·m^-1·K^-1 at 700 K).At 700 K,the thermoelectric figure of merit of the optimal p-type doping is close to 1.76,which is higher than 0.8 of ZrSb at 700 K and 1.4 of PtTe at 750 *** work clearly demonstrates the advantages of Au2S as a TE material and would greatly inspire further experimental studies and verifications.

关键词： first principles calculation thermodynamic transport properties

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science china Earth Sciences 2025年第1期 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng wu School of Earth and Space Sciences University of Science and Technology of China cAS center of Excellence in comparative Planetary Studies

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress between different tectonic modes ***, the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number, but decreases between other tectonic modes. Furthermore, we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate, with the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa, which aligns with the strength of serpentinized mantle rock determined by experimental petrography. If the Archean mantle was 300°c warmer than it is today, then the Earth was in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

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The Effect of Titania-coating on Electrochemical characteristics of cMS in Pc-Based Electrolyte

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复旦学报（自然科学版） 2005年第5期44卷 857-858页

作者： J. cao L.c. yang T. Zhang y.P. wu H.Q. wu Deparment of chemistry ＆ Shanghai Key Laboratory of Molecular catalysis and Innovative Materials Fudan University Shanghai 200433 China

Lithium-ion batteries have been widely used in portable electronic devices due to their high voltage and high energy density. Most research has concentrated on improving their performance such as capacity, cycling characteristics and low temperature range. Propylene carbonate (Pc)-based electrolytes are more desirable than ethylene carbonate (Ec)-based electrolytes because of their low-temperature characteristics[1]. Unfortunately, Pc is not used in commercial lithium-ion batteries because solvent decomposition and graphite exfoliation occur when lithium intercalates[2].

关键词：锂离子电池二氧化钛丙烯碳酸盐溶胶凝胶体电化学

Male androgen deficiency： a multisystem syndrome

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Asian Journal of Andrology 2014年第2期16卷 159-160,I0006页

作者： Mathis Grossmann Frederick c wu Department of Medicine Austin Health University of Melbourne Melbourne Department of Endocrinology Austin Health Melbourne Victoria Australia Andrology Research Unit Centre for Endocrinology and Diabetes Institute of Human Development University of Manchester Central Manchester University Hospitals NHS Foundation Trust Old St Mary's Building Hathersage Road Manchester United Kingdom.

Androgens have important effects on .multiple organ systems, which play critical roles in the regulation of a myriad of male sexual, somatic, and behavioral functions critical to lifelong health. Androgen deficiency is a multisystem syndrome, presenting with typical clinical features in association with a confirmed low serum testosterone level. The clinical presentation of androgen deficiency is modified by age and other patient-specific characteristics such as comorbidities, genetic, environmental, and sociocultural factors.

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Quasi-variable Discount Rates and Market Volatility: An Empirical Study

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 515-530页

作者： Pengju Zhao Wei Zhang Xi wu Peter c.coyte Economics and Management School Zhongyuan University of TechnologyZhengzhou450007China Economics and Management School Tianjin UniversityTianjin300072China Economics and Management School System and Industrial Engineering Research CentreZhongyuan University of TechnologyZhengzhou450007China Institute of Health Policy Management and Evaluation(HPME)School of Public HealthUniversity of TorontoTorontoM5R 0A3Canada

This paper proposes an assumption of quasi-variable discount rates to explain the excess volatility puzzle of stock market. Under the assumption, the ARMAX model is derived based on the ccAPM model and cRRA utility function to describe the linear relationship between the discount rate and the consumption growth rate. We conducted empirical research on this model using historical data of the US stock market. The results confirm a significantly negative relationship between consumption growth rate and discount rate. Subsequently, the results of Monte carlo simulation show that given the risk preference coefficient and dividend sequence, the rational expectations price fluctuation obtained under the assumption of quasivariable discount rate is the largest.

关键词： Stochastic discount factor market volatility dividend discount model ARMAX

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多源固废协同制备土壤固化剂及固化机理

森林工程 2025年第1期41卷 195-204页

作者：褚锋吴思吴传山马亚李骏山东高速建设管理集团有限公司济南230000 山东高速济德公路有限公司山东德州253000 山东高速工程检测有限公司济南230002

为实现冶金固废材料的高值化、规模化利用,采用冶金固废材料(高炉矿渣、粉煤灰、电石渣、石膏)协同制备土壤固化剂,通过正交配比优化试验研究不同固废材料对固化土力学性能的影响并获取最优的参数配方。系统研究固废基固化剂(SWc)固化... 详细信息

为实现冶金固废材料的高值化、规模化利用,采用冶金固废材料(高炉矿渣、粉煤灰、电石渣、石膏)协同制备土壤固化剂,通过正交配比优化试验研究不同固废材料对固化土力学性能的影响并获取最优的参数配方。系统研究固废基固化剂(SWc)固化土的力学性能(无侧限抗压强度、劈裂强度、延迟成型)和耐候性能(水稳定性、冻融循环),并与PO 42.5硅酸盐水泥(OPc)进行对比。结果表明,电石渣对固化剂体系起到重要作用,合理的石膏掺量对强度增长有积极作用;固化土的强度随SWc掺量和养护龄期的增加而增大,4%掺量下的固化土7 d无侧限抗压强度大于1 MPa,劈裂强度与OPc固化土基本相当;SWc固化土表现出更久的施工容许延迟时间,拌和后12 h内强度无下降趋势;掺量大于5%时水稳定系数大于90%,同掺量下抗冻系数与水泥相比提高3%~5%,具备良好的水稳定性与抗冻性;X射线衍射(XRD)和扫描电子显微镜(SEM)分析表明,SWc固化土在水化过程中会生成膨胀性水化产物钙矾石(AFt)和硅酸钙(c-S-H),钙矾石晶体对改善固化土的劈裂强度和抵抗开裂变形能力提高作用显著。

关键词：道路工程固化剂力学性能固化土工业固废

Islet separation and islet cell culture in vitro from human embryo-pancreas

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World Journal of Gastroenterology 1999年第5期5卷 458-460页

作者： yuan Z wu Gy He yS Shao cM Zhan y Kunming Med coll Dept Histol & Embryol Kunming 650031 Yunnan Province Peoples R China First Affiliated Hosp Kunming Med Coll Dept Nucl Med Kunming 650032 Yunnan Province Peoples R China Kunming Med coll Dept Biol Kunming 650031 Yunnan Province Peoples R China

INTRODUcTIONDiabetes mellitus is the most common disease and its death rate ranks the 8th in the world. Up to now, its incidence has a tendency to increase[1]. Since disorder of sugar metabolism might result in microvascular degeneration and injury of important human organs, it will endanger human health seriously. In 1969, younszai first reported the method that could decrease diabetes symptoms by islet tissue transplantation. In 1981, our country began to treat diabetes type Ⅰ by transplanting cultured islet tissues. In our study, we digested the pieces of pancreas with collagenase and made morphological observation on islet cells cultured for 3d, 5d, 7d, 9d and 13d respectively, and the contents of insulin and c-peptide in the supernatant were detected by radioimmunoassay. The experimental model of rabbit diabetes was established, and certain curative effect was achieved in the treatment of experimental diabetes in rats.

关键词： cell culture islet cell islets of langerhans transplantetion pancreas/ embryology

Particulate Flow Simulation via a Boundary condition-Enforced Immersed Boundary-Lattice Boltzmann Scheme

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communications in computational Physics 2010年第4期7卷 793-812页

作者： J.wu c.Shu Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260

A boundary condition-enforced immersed boundary-lattice Boltzmannmethod (IB-LBM) for the simulation of particulate flows is presented in this paper. Ingeneral, the immersed boundary method (IBM) utilizes a discrete set of force densityto represent the effect of boundary. In the conventional IB-LBM, such force density ispre-determined, which cannot guarantee exact satisfaction of non-slip boundary condition. In this study, the force density is transferred to the unknown velocity correctionwhich is determined by enforcing the non-slip boundary condition. For the particulateflows, accurate calculation of hydrodynamic force exerted on the boundary of particlesis of great importance as it controls the motion of particles. The capability of presentmethod for particulate flows is depicted by simulating migration of one particle in asimple shear flow and sedimentation of one particle in a box and two particles in achannel. The expected phenomena and numerical results are achieved. In addition,particle suspension in a 2D symmetric stenotic artery is also simulated.

关键词： Lattice Boltzmann method immersed boundary method non-slip boundary condition particulate flow two-dimensional

Thrombolysis for ischaemic stroke despite direct oral anticoagulation

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Stroke & Vascular Neurology 2024年第5期9卷 464-466页

作者： Jan c.Purrucker Thomas R.Meine Duncan Wilson ying Xian Teddy y.wu David J.Seiffge Department of Neurology Heidelberg University HospitalHeidelbergGermany Department of Neurology and Stroke Research center Bern Inselspital BernUniversity of BernBernSwitzerland New Zealand Brain Research Institute ChristchurchNew Zealand The University of Texas Southwestern Medical center DallasTexasUSA Department of Neurology Christchurch HospitalChristchurchNew Zealand

Intravenous thrombolysis is not recommended in anticoagulated patients receiving direct oral anticoagulants(DOAcs)and a recent intake within the last 48hours in US and European ***,three observational studies now suggest safety of thrombolysis in patients with recent intake of DOAcs,and thus support previous experimental *** this perspective,the current evidence and practical consequences are discussed.

关键词： intake patients consequences

Spray granulation of Fe and c nanoparticles and their impedance match for microwave absorption

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Journal of Materials Science & Technology 2018年第3期34卷 496-502页

作者： H.Huang y.Gao c.F.Fang A.M.wu X.L.Dong B.S.Kim J.H.Byun G.F.Zhang D.y.Zhou Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China composites Research Division Korea Institute of Materials Science797 Changwon-daeroSeongsan-guChangwonGyeongnam642-831Republic of Korea

The microwave absorbents of Fe and c nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol （PVA） as binder by spray granulation method, The electromagnetic parameters of Fe and c composite particles were analyzed by vector network. The complex permittivity and magnetic permeability of Fe and c composite particles matched well with increasing c nanoparticle content, and then the microwave loss property was improved. A minimum reflection loss （RL） of -42.7 dB at 3.68 GHz for a composite with 4.6 mm in thickness can be obtained when the content ratio of the c nanoparticles, the modified Fe nanoparticles and the PVA is 21：49：30 （Sample 3）.

关键词： Dielectric loss Magnetic loss Spray granulation method Impedance match