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Chinese Journal of Polymer Science 2021年第12期39卷 1680-1694页

作者： Wen-Jie Yu Guan-Cheng Shen Xiao-Wei Zhou Mao-Yuan li Yun Zhang hua-Min Zhou De-Qun li State Key Laboratory of Materials Processing and Die Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Entanglement network is an important structural feature in concentrated polymer solutions and polymer melts,which has a great influe nee on the transie nt rheological behavior and molecular con figurati on ***,the existi ng constitutive models have limitations in describi ng the influe nee of dyn amic entan glement behavior on molecular chain motion,resulti ng in inaccurate descriptions of the transient rheological ***,a molecular con figuration evoluti on model for polymer solutions considering the dyn amic entanglement effect is proposed by introducing an intermolecular force that changes with the orientation of the molecular chain in this *** intermolecular force is introduced by consider!ng the friction coefficient as anisotropic,and the orientation effect is considered by introducing an excluded volume depende nt an isotropic diffusi *** proposed model can better describe the stress relaxation,stress growth,and dielectric an isotropy of polymer soluti ons compared with the an isotropy FENE model and FENE *** addition,the in fluence of different model parameters on the transient and steady shear response of polymer soluti on is investigated,and the results show that the in fluence of volume loss on the fricti on anisotropy factor k0 in creases as the solution concen tration in creases.

关键词： Molecular configuration Polymer solutions Transient rheology Dumbbell model

Tolerance of neurite outgrowth to Rho kinase inhibitors decreased by cyclooxygenase-2 inhibitor

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Neural Regeneration Research 2012年第34期7卷 2705-2712页

作者： Weigang Duan ling Que Xiaoman Lv Qifeng li hua Yin Luyong Zhang Key Laboratory of Molecular Biology for Sinomedicine Yunnan University of Traditional Chinese Medicine New Drug Screening Center China Pharmaceutical University

In this study, PC12 Adh cells and Neuro-2a cells were treated with Rho-associated kinase inhibitors （Y27632 and Fasudil）, a cyclooxygenase-1 selective inhibitor （SC560）, and a cyclooxygenase-2 inhibitor （NS398）. We found that these cells became tolerant to Rho-associated kinase inhibitors, as neurite outgrowth induced by these inhibitors diminished following more than 3 days of exposure in either cell line. The proteins cyclooxygenase-2 and cytosolic prostaglandin E synthetase were upregulated at day 3. NS398 decreased the tolerance to neurite outgrowth induction in both cell lines, whereas SC560 had almost no effect. These findings indicate that cells become tolerant to neurite outgrowth induced by Rho-associated kinase inhibitors, this is at least partly associated with upregulation of proteins involved in the cyclooxygenase-2 pathway, and cyclooxygenases-2 inhibition prevents this tolerance.

关键词： Rho-associated kinase inhibitors Y27632 fasudil neurite cyclooxygenase 2 inhibitors drugtolerance

Local Responses to Macro Development Policies and Their Effects on Rural System in China's Mountainous Regions:The Case of Shuanghe Village in Sichuan Province

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Journal of Mountain Science 2013年第4期10卷 588-608页

作者： li Yu-rui liU Yan-sui LONG hua-lou WANG Jie-yong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of Sciences

China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.

关键词： Local responses Western DevelopmentProgram Grain for Green Project Agriculturalsupport policies Building new countryside Ruralpolicy evaluation

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2012年第9期12卷 1197-1242页

作者： xiang-Qun Cui Yong-Heng Zhao Yao-Quan Chu Guo-Ping li Qi li li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong liu Hao-Tong Zhang De-hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-hua Jiang xiang Jiang Zi-Bo Jiang Ge Jin Ai-hua li Yan li Ye-Ping li Guan-Qunliu Zhi-Gang liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-hua Zhou Jie Zhu Si-Cheng Zou National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China yzhao @ *** Nanjing Institute of Astronomical Optics and Technology National Astronomical ObservatoriesChinese Academy of Sciences Nanjing 210042 China University of Science and Tecfinologyof China Hefei 230026 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Architecture Design and Research Chinese Academy of Sciences Beijing 100190China

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.

关键词： techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction

Coherent Resonance of a Strong Electromagnetic Wave Beam to a Standing Gravitational Wave

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Chinese Physics Letters 1999年第1期16卷 12-14页

作者： li Fang-yu TANG Meng-xi WEN De-hua Department of Physics Chongqing UniversityChongqing 400044 Department of Physics Zhongshan UniversityGuangzhou 510275

Coherent resonant conditions of a strong electromagnetic(EM)wave beam propagating in a static magnetic field to a standing gravitational wave(GW)are *** is found that under the resonant conditions not only first-order perturbed energy fluxes(PEFs)propagating along the same and opposite directions to the background EM wave beam can be generated,but also radial and tangential PEFs which are perpendicular to the above directions can be *** results might provide a new way to display the resonant response induced by the standing GW with h=10-35 andλg=*** at the level of the single photon avalanche effect.

关键词： effect. resonant directions

Three-Dimensional Analytical Modeling of Axial-Flux Permanent Magnet Drivers

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Computers, Materials & Continua 2023年第4期75卷 259-276页

作者： Wenhui li Dazhi Wang Shuo Cao Deshan Kong Sihan Wang Zhong hua Northeastern University Shenyang110819China Shenyang Polytechnic College Shenyang110819China

In this paper, the axial-flux permanent magnet driver is modeledand analyzed in a simple and novel way under three-dimensional cylindricalcoordinates. The inherent three-dimensional characteristics of the deviceare comprehensively considered, and the governing equations are solved bysimplifying the boundary conditions. The axial magnetization of the sectorshapedpermanent magnets is accurately described in an algebraic form bythe parameters, which makes the physical meaning more explicit than thepurely mathematical expression in general series forms. The parameters of theBessel function are determined simply and the magnetic field distribution ofpermanent magnets and the air-gap is solved. Furthermore, the field solutionsare completely analytical, which provides convenience and satisfactoryaccuracy for modeling a series of electromagnetic performance parameters,such as the axial electromagnetic force density, axial electromagnetic force,and electromagnetic torque. The correctness and accuracy of the analyticalmodels are fully verified by three-dimensional finite element simulations and a15 kW prototype and the results of calculations, simulations, and experimentsunder three methods are highly consistent. The influence of several designparameters on magnetic field distribution and performance is studied and *** results indicate that the modeling method proposed in this papercan calculate the magnetic field distribution and performance accurately andrapidly, which affords an important reference for the design and optimizationof axial-flux permanent magnet drivers.

关键词： Three-dimensional analytical modeling cylindrical coordinates magnetic field distribution parameter sensitivity analysis performance measurement

An efficient labeled memory system for learned indexes

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Fundamental Research 2024年第3期4卷 651-659页

作者： Yuxuan Mo Jingnan Jia Pengfei li Yu hua huazhong University of Science and Technology Wuhan 430074China

The appearance and wide use of memory hardware bring significant changes to the conventional vertical memory hierarchy that fails to handle contentions for shared hardware resources and expensive data *** deal with these problems,existing schemes have to rely on inefficient scheduling strategies that also cause extra temporal,spatial and bandwidth *** on the insights that the shared hardware resources trend to be uniformly and hierarchically offered to the requests for co-located applications in memory systems,we present an efficient abstraction of memory hierarchies,called Label,which is used to establish the connection between the application layer and underlying hardware *** on labels,our paper proposes LaMem,a labeled,resource-isolated and cross-tiered memory system by leveraging the way-based partitioning technique for shared resources to guarantee QoS demands of applications,while supporting fast and low-overhead cache repartitioning ***,we customize LaMem for the learned index that fundamentally replaces storage structures with computation models as a case study to verify the applicability of *** results demonstrate the efficiency and efficacy of LaMem.

关键词： Heterogeneous memory system Cache hierarchy Data movement Resource contention Learned index

Primary lymphoblastic B-cell lymphoma of the stomach:A case report

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World Journal of Gastroenterology 2008年第19期14卷 3101-3104页

作者： Miao-Xia He Ming-hua Zhu Wei-Qiang liu li-li Wu Xiong-Zeng Zhu Department of Pathology Changhai Hospital Second Military Medical University Shanghai 200433 China Department of Pathology Tumor Hospital Fudan University Shanghai 200032 China

Primary stomach lymphoblastic B-cell lymphoma (B-LBL) is a rare tumor. We describe a primary stomach B-LBL in a 38 years old female who presented with nonspecific complaints of fatigue and vomiting for 2 mo. Gastrofiberscopy revealed a large gastric ulcer, which was successfully resected. Pathology showed a lymphoblastic cell lymphoma arising from the stomach, and there was no evidence of disease at any extrastomach site. Immunohistochemical staining and gene rearrangement studies supported that the stomach tumor was a clonal B-cell lymphoma. Therefore, the diagnosis of B-LBL was made based on the stomach specimen.

关键词： Primary stomach lymphoma Lymphoblastic lymphoma B-cell

Experiment and numerical simulation of melt convection and oxygen distribution in 400-mm Czochralski silicon crystal growth

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Rare Metals 2017年第2期36卷 134-141页

作者： Ran Teng Yang li Bin Cui Qing Chang Qing-hua Xiao Guo-Hu Zhang National Engineering Research Center for Semiconductor Materials Beijing 100088China Semiconductor Materials Co. LtdGeneral Research Institute for Nonferrous MetalsBeijing 100088China

Single-crystalline silicon materials with large dimensions have been widely used as assemblies in plasma silicon etching ***,information about large-diameter low-cost preparation technology has not been sufficiently *** this paper,it was focused on the preparation of 400-mm silicon（100） crystal lightly doped with boron from *** *** uniformity and oxygen concentration of the silicon crystal were investigated by direct-current（DC） four-point probes method and Fourier transform infrared spectroscopy（FTIR）,*** global heat transfer,melt flow and oxygen distribution were calculated by finite element method（FEM）.The results show that *** zones can replace conventional 32 *** to grow 400-mm-diameter silicon single *** change in crucible diameter can save energy,reduce cost and improve *** trend of oxygen distribution obtained in calculations is in good agreement with experimental *** present model can well predict the 400-mm-diameter silicon crystal growth and is essential for the optimization of furnace design and process condition.

关键词： Silicon crystal preparation Computer simulation Czochralski method Heat transfer Melt flow Oxygen distribution

Humic Acid and Iron Chelation Modified Anode Improves the Electrochemical Performance of Marine Sediment Microbial Fuel Cell

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Journal of Ocean University of China 2022年第2期21卷 388-394页

作者： FU Yubin CHEN Jiaqi CHEN Yan huaNG xiang li Yang ZHANG huaijing ZAI Xuerong School of Materials Science and Technology Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China College of Marine Geosciences Ocean University of ChinaQingdao 266100China

Marine sediment microbial fuel cell(MSMFCs)can be utilized as a long lasting power source to drive small instruments to work for long time on ocean floor and its higher power has a significant meaning for practical *** modification can greatly improve the performance of ***,humic acid(HA)and humic acid-iron ion complex(HA-Fe)were used to modify the anode for constructing a better *** results indicated that HA-Fe modified anode,better than HA modification,significantly improved the MSMFCs cell power *** maximum power density of HA-Fe modified MSMFCs is 165.3 mW m−2,which are 6.5-folds of blank *** number of microorganisms on anode,redox activity,and relative kinetic activity were 1.8-,6.1-,and 13.1-folds of blank MSMFCs,*** MSMFCs improvement would be attributed to the electron transfer media of HA and the valence conversion of Fe ions.A synergistic interaction between the naturally occurring HA and Fe ions on the anodic surface in marine sediments would make the modified anodes have‘renewable’characteristics,which is beneficial for the MSMFCs to maintain its long-term higher power.

关键词： marine sediment microbial fuel cells humic acid and iron complex modified anode electrochemical performance