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A p-version embedded model for simulation of concrete temperature fields with cooling pipes

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Water Science and Engineering 2015年第3期8卷 248-256页

作者： Sheng Qiang Zhi-qiang xie rui Zhong College of Water Conservancy and Hydropower Engineering Hohai University Lyles School of Civil Engineering Purdue University Department of Material and Structure Changjiang River Scientific Research Institute School of Engineering University of Connecticut

Pipe cooling is an effective method of mass concrete temperature control, but its accurate and convenient numerical simulation is still a cumbersome problem. An improved embedded model, considering the water temperature variation along the pipe, was proposed for simulating the temperature field of early-age concrete structures containing cooling pipes. The improved model was verified with an engineering example. Then, the p-version self-adaption algorithm for the improved embedded model was deduced, and the initial values and boundary conditions were examined. Comparison of some numerical samples shows that the proposed model can provide satisfying precision and a higher efficiency. The analysis efficiency can be doubled at the same precision, even for a large-scale element. The p-version algorithm can fit grids of different sizes for the temperature field simulation. The convenience of the proposed algorithm lies in the possibility of locating more pipe segments in one element without the need of so regular a shape as in the explicit model.

关键词： Concrete temperature field Cooling pipe Embedded model p-version Numerical simulation

Modulation of photovoltaic behavior of dye-sensitized solar cells by electron donors of porphyrin dyes and cosensitization

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Chinese Chemical Letters 2015年第7期26卷 899-904页

作者： Bin Chen Lu Sun Yong-shu xie Shanghai Key Laboratory of Functional Materials Chemistry East China University of Science and Technology Department of Theoretical Chemistry and Biology School of Biotechnology KTH Royal Institute of Technology

Porphyrin dyes have received great attention due to their excellent photovoltaic performance in dye- sensitized solar cells （DSSCs）. In this work, dyes XCI-XC3 were synthesized by introducing various numbers of bis（4-methoxyphenyl）amino and p-hexyloxyphenyl groups to porphyrin meso-positions. The XC1 molecule contains two p-hexyloxyphenyl groups, and its DSSCs showed the power conversion efficiency of 4.81%. For XC2 and XC3, the replacement of p-hexyloxyphenyl with diphenylamino groups can effectively enhance the light harvesting around 500 nm. However, the highest occupied molecular orbitals （HOMOs） were elevated too much, which suppressed the dye regeneration processes, leading to low cell efficiencies of 2.51% and 1.27% for XC2, and XC3, respectively. To further improve the cell performance, an anthracene derivative Cl was used as the cosensitizer for XCl, which increased both the Jsc and Voc values, with an improved efficiency of 5.75：g.

关键词： Porphyrins DSSCs Cosensitizer Theoretical calculation

Evaluation and Projection of Population Exposure to Temperature Extremes over the Beijing−Tianjin−Hebei Region Using a High-Resolution Regional Climate Model RegCM4 Ensemble

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Advances in Atmospheric Sciences 2024年第6期41卷 1132-1146页

作者： Peihua QIN Zhenghui xie rui HAN Buchun LIU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China

Temperature extremes over rapidly urbanizing regions with high population densities have been scrutinized due to their severe impacts on human safety and *** of all,the performance of the regional climate model RegCM4 with a hydrostatic or non-hydrostatic dynamic core in simulating seasonal temperature and temperature extremes was evaluated over the historical period of 1991–99 at a 12-km spatial resolution over China and a 3-km resolution over the Beijing−Tianjin−Hebei(JJJ)region,a typical urban agglomeration of *** of spatial distributions of temperature extremes over the JJJ region using RegCM4 with hydrostatic and non-hydrostatic cores showed high spatial correlations of more than 0.8 with the *** a warming climate,temperature extremes of annual maximum daily temperature(TXx)and summer days(SU)in China and the JJJ region showed obvious increases by the end of the 21st century while there was a general reduction in frost days(FD).The ensemble of RegCM4 with different land surface components was used to examine population exposure to temperature extremes over the JJJ *** exposure to temperature extremes was found to decrease in 2091−99 relative to 1991−99 over the majority of the JJJ region due to the joint impacts of increases in temperature extremes over the JJJ and population decreases over the JJJ region,except for downtown ***,changes in population exposure to temperature extremes were mainly dominated by future population ***,we quantified changes in exposure to temperature extremes with temperature increase over the JJJ *** study helps to provide relevant policies to respond future climate risks over the JJJ region.

关键词： CMIP6 convection-permitting population exposure RegCM4 temperature extremes

Minimizing Outage Probability Driven Wireless Backhaul Scheme in Heterogeneous Networks

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China Communications 2022年第6期19卷 248-262页

作者： Zhenxing Li rui xie Kai Luo Tao Jiang Research Center of 6G Mobile Communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Shanghai Electric Control Research Institute Shanghai 200092China

Heterogeneous networks(Het Nets)attracts a lot of attention due to its high capacity and large coverage for future communication ***,with the large-scale deployment of small cells,HetNets bears dramatically increasing backhaul,which leads to a decrease of the outage *** improve the outage performance of Het Nets,we propose a wireless backhaul scheme for a two-layer HetNets,which automatically switches the three basic modes of orthogonal multiple access(OMA),nonorthogonal multiple access(NOMA)and cooperative non-orthogonal multiple access(CNOMA).First,we analyze the backhaul capacity and outage performance of these three basic ***,we design the power allocation schemes based on minimizing outage probability for NOMA and *** the designed power allocation schemes,we propose a wireless backhaul scheme that switches the three modes according to the channel quality among different base stations(BSs).Moreover,the closed-form of the corresponding outage probability is *** with the three basic modes,the proposed wireless backhaul scheme can achieve the best outage performance and a higher backhaul ***,all the analytical results are validated by simulations.

关键词： Het Nets wireless backhaul NOMA outage probability backhaul capacity

Wavefronts of a Nonlocal State-dependent Time Delay Model

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Acta Mathematica Sinica,English Series 2020年第1期36卷 77-92页

作者： rui Jun xie Rong YUAN Zhi Hui YANG School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu 233030P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

This paper is concerned with the travelling wavefronts of a nonlocal dispersal cooperation model with harvesting and state-dependent delay,which is assumed to be an increasing function of the population density with lower and upper ***,state-dependent delay is introduced into a nonlocal reaction-diffusion *** conditions of Schauder's fixed point theorem are proved by constructing a reasonable set of functionsΓ(see Section 2)and a pair of upper-lower solutions,so the existence of traveling wavefronts is *** present study is continuation of a previous work that highlights the Laplacian diffusion.

关键词： Nonlocality state-dependent delay cooperation traveling wavefronts

Polymorph Structures,Rich Physical Properties and Potential Applications of Two-Dimensional MoTe_(2),WTe_(2) and Their Alloys

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Chinese Journal of Chemistry 2022年第8期40卷 989-1004页

作者： rui Zhou Juanxia Wu Yuansha Chen Liming xie CAS Key Laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Condensed Matter Physics&Institute of Physics Chinese Academy of SciencesBeijing 100190China

2D MoTe_(2),WTe_(2) and their alloys have received intensive research interest because of their unique properties arising from the polymorph structures,chiral anomaly,strong spin-orbit coupling,and so *** this review,we have summarized recent advances of 2D MoTe_(2),WTe_(2) and their alloys from the materials perspective with special focus on the synthesis,electrical and magnetic *** polymorph structures of MoTe_(2),WTe_(2) and their alloys are presented first and then the preparation methods have been discussed,including mechanical exfoliation,metal-organic chemical vapor deposition(MOCVD),molecular beam epitaxy(MBE),chemical vapor deposition(CVD)and solution-phase *** that,fascinating physical properties arising from the large spin-orbit coupling and non-trivial band structures have been summarized,including phase transition,optoelectri-cal properties,Weyl semimetal state,superconducting and *** last,potential device applications of MoTe_(2),WTe_(2) and their alloys are reviewed,including field-effect transistors(FETs),memory devices,spin-to-charge conversion,solar cells,and so on.

关键词： 2D materials Transition metal tellurides Alloys Crystal growth Electronic structure

Theoretical Study on the Dehydrogenation Reaction of H_2S by VS^+ (~3Σ^-)

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1111-1116页

作者： GAO shu-Lin LIU Zheng-Mei xie Xiao-Guang Department of Chemistry Yunnan University Kunming 650091 China School of Physics and Chemistry Guizhou Normal University Guiyang 550001 China

The dehydrogenation reaction of H2S by the ^3Σ^- ground state of VS^＋： VS^＋＋ H2S → VS2^＋＋ H2 has been studied by using Density Functional Theory （DPT） at the B3LYP/DZVP level. It is found that the reaction proceeds along two possible pathways （A and B） yielding two isomer dehydrogenation products VS2^＋-1 （^3B2） and VS2^＋-2 （^3A1）, respectively. For both pathways, the reaction has a two-step-reaction mechanism that involves the migration of two hydrogen atoms from S2 to V^＋, respectively. The migration of the second hydrogen via TS3 and that of the first via TS4 are the rate-determining steps for pathways A and B, respectively. The activation energy is 17.4 kcal/mol for pathway A and 22.8 kcal/mol for pathway B relative to the reactants. The calculated reaction heat of 9.9 kcal/mol indicates the endothermicity of pathway A and that of -11.9 kcal/mol suggests the exothermicity of pathway B.

关键词： density functional theory cationic transition metal sulfide,dehydrogenation reaction reaction mechanism

Development of subdural empyema from subdural effusion after suppurative encephalitis:A case report

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World Journal of Clinical Cases 2023年第10期11卷 2315-2320页

作者： rui-Xi Yang Bei Chen Yun Zhang Yao Yang shu xie Lin He Jian Shi Department of Infectious Diseases Mianyang Central HospitalMianyang 621000Sichuan ProvinceChina Department of Psychosomatic Medicine Mianyang Central HospitalMianyang 621000Sichuan ProvinceChina Department of Psychosomatic Medicine Mianyang Central HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaMianyang 621000Sichuan ProvinceChina

BACKGROUND Chronic subdural effusion is very common in the cranial imaging of middle-aged and older ***,we report a patient misdiagnosed with subdural effusion,who was eventually diagnosed with chronic subdural empyema(SDE)caused by Streptococcus *** SUMMARY A 63-year-old man was brought to our emergency room with a headache,vomiting,and disturbed *** tomography(CT)revealed a bilateral subdural effusion at the top left side of the frontal *** fluid examination after lumbar puncture indicated suppurative meningitis,which improved after anti-infective ***,the patient then presented with acute cognitive dysfunction and right limb *** CT showed an increase in left frontoparietal subdural effusion,disappearance of the left lateral ventricle,and a shift of the midline to the *** burr hole drainage showed SDE that was culture-positive for Streptococcus *** condition improved after adequate drainage and antibiotic *** Patients with unexplained subdural effusion,especially asymmetric subdural effusion with intracranial infection,should be assessed for chronic *** surgical treatment may be beneficial.

关键词： Subdural effusion Subdural empyema Streptococcus pneumoniae Meningoencephalitis Drainage Case report

A TrustEnclave-Based Architecture for Ensuring Run-Time Security in Embedded Terminals

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Tsinghua Science and Technology 2017年第5期22卷 447-457页

作者： rui Chang Liehui Jiang Wenzhi Chen Yaobin xie Zhongyong Lu the State Key Laboratory of Mathematic Engineering and Advanced Computing the Department of Computer Zhejiang University

The run-time security guarantee is a hotspot in current cyberspace security research, especially on embedded terminals, such as smart hardware as well as wearable and mobile devices. Typically, these devices use universal hardware and software to connect with public networks via the Internet, and are probably open to security threats from Trojan viruses and other malware. As a result, the security of sensitive personal data is threatened and economic interests in the industry are compromised. To address the run-time security problems efficiently, first, a TrustEnclave-based secure architecture is proposed, and the trusted execution environment is constructed by hardware isolation technology. Then the prototype system is implemented on real TrustZone-enabled hardware devices. Finally, both analytical and experimental evaluations are provided. The experimental results demonstrate the effectiveness and feasibility of the proposed security scheme.

关键词： run-time security trusted execution environment hardware isolation TrustZone