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communications in Theoretical Physics 2021年第12期73卷 78-85页

作者： Yu-Han Ma c P Sun hui Dong Graduate School of c.ina Academy of Engineering Physics Beijing 100193China Beijing computational Science Research center Beijing 100193China

The efficiency at the maximum power(EMP)for finite-time carnot engines established with the low-dissipation model,relies significantly on the assumption of the inverse proportion scaling of the irreversible entropy generationΔS^(ir)on the operation timeτ,i.e.ΔS^(ir)∝1/τ.The optimal operation time of the finite-time isothermal process for EMP has to be within the valid regime of the inverse proportion ***,such consistency was not tested due to the unknown coefficient of the 1/τ-*** this paper,we reveal that the optimization of the finite-time two-level atomic carnot engines with the low-dissipation model is consistent only in the regime ofη_(c)c.is the carnot efficiency,andδis the compression ratio in energy level difference of the heat engine *** the large-η_(c)regime,the operation time for EMP obtained with the low-dissipation model is not within the valid regime of the 1/τ-scaling,and the exact EMP of the engine is found to surpass the well-known boundη_(c)=η_(c)/(2-η_(c)).

关键词： finite-time thermodynamics low-dissipation model quantum heat engine efficiency at maximum power irreversible entropy generation

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三峡水库微塑料与悬沙的聚集特性及作用机制

湖泊科学 2025年第1期37卷 149-158页

作者：刘洁张智超李霞朱丽帆蒋晖重庆交通大学国家内河航道工程技术研究中心重庆400074 重庆交通大学河海学院重庆400074

本文依据三峡库区悬沙矿物组成和泥沙级配为依据配置沙样,选择长江上游典型微塑料PMMA和PS,在自制大型水箱中开展水流剪切作用下微塑料和泥沙异质聚集实验,分析微泥絮团的形态特征和聚集机制。结果表明在水流紊动剪切作用下,相比泥沙同... 详细信息

本文依据三峡库区悬沙矿物组成和泥沙级配为依据配置沙样,选择长江上游典型微塑料PMMA和PS,在自制大型水箱中开展水流剪切作用下微塑料和泥沙异质聚集实验,分析微泥絮团的形态特征和聚集机制。结果表明在水流紊动剪切作用下,相比泥沙同质聚集的絮团粒径,微泥异质聚集的絮团粒径更大,且每毫升样品中微泥絮团上的微塑料吸附数量随水流剪切率增大而迅速增加。扫描电镜和能谱分析结果表明,在水动力条件下泥沙与PMMA、PS微球发生异质聚集,聚集过程中存在电子转移和化学态的转变,并产生不饱和键(c c)。由于PMMA官能团的结合能变化比PS大,此过程失电子更多、表面电荷更大,更容易与泥沙发生聚集。

关键词：微塑料悬沙微泥絮团形貌聚集机制三峡水库

Screening and prevention of hepatitis c virus reac.ivation during chemotherapy

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World Journal of Gastroenterology 2021年第31期27卷 5181-5188页

作者： Yuan-Rung Li Tsung-hui Hu Wen-c.i chen Ping-i Hsu hui-chun chen Department of internal Medicine Kaohsiung Veterans General HospitalKaohsiung 813Taiwan Department of internal Medicine Chang Gung University College of MedicineKaohsiung 833Taiwan Division of Gastroenterology and Hepatology Department of Internal MedicineKaohsiung Veterans General HospitalKaohsiung 813Taiwan Department of Radiation Oncology Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of MedicineKaohsiung 833Taiwan

Hepatitis c virus(HcV)reac.ivation occurs in 23%of HcV-infected cancer patients rec.iving ***-three percent of the patients with reac.ivation of HcV during chemotherapy develop a hepatitis *** of the cancer patients with HcV reac.ivation have an unremarkable c.inical course following an HcV-related hepatitis flare during ***,26%–57%of the cancer patients developing an acute flare of chronic hepatitis c during chemotherapy require unanticipated discontinuation or dose reduc.ion of chemotherapy,which results in deleterious changes in the cancer treatment *** an optimal strategy for HcV screening in cancer patients rec.iving chemotherapy has not been established,universal pre-chemotherapy HcV testing for patients with hematological malignancies is recommended by current *** the currently approved direct-ac.ing antivirals(DAAs)can be used in cancer patients,but the use of DAAs during chemotherapy should avoid drug–drug interac.ions between chemotherapy and antiviral *** there are no contraindications or anticipated drug–drug interac.ions,DAAs treatment can be administered before,during,or after *** conclusion,HcV reac.ivation occurs in approximately one-fourth of HcV-infected cancer patients rec.iving *** HcV-related hepatitis flare during chemotherapy may lead to the discontinuation of potentially life-saving ***,universal HcV screening is recommended in hematological malignancy patients before chemotherapy,but there is no evidence-based guideline for other cancer *** treatment can cure HcV infec.ion and prevent HcV reac.ivation during chemotherapy.

关键词： Hepatitis c virus chemotherapy Screening Reac.ivation Hepatitis flare

Emergent Z2 topological invariant and robust helical edge states in two-dimensional topological metals

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Science c.ina(Physics,Mechanics & Astronomy) 2020年第10期63卷 105-110页

作者： chui-Zhen chen Hua Jiang Dong-hui Xu X.c.Xie institute for Advanced Study and School of Physical Science and Technology Soochow UniversitySuzhou 215006China Department of Physics Hubei UniversityWuhan 430062China international center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China cAS center for Excellence in Topological Quantum computation University of Chinese Academy of SciencesBeijing 100190China Beijing Academy of Quantum information Sciences Beijing 100193China

in this work,we study the effects of disorder on topological metals that support a pair of helical edge modes deeply embedded inside the gapless bulk ***,we predict that a quantum spin Hall(QSH)phase can be obtained from such topological metals without opening a global band *** be specific,disorder can lead to a pair of robust helical edge states which is protected by an emergent Z2 topological invariant,giving rise to a quantized conductance plateau in transport *** results are instruc.ive for solving puzzles in various transport experiments on QSH materials that are intrinsically *** work also will inspire experimental realization of the QSH effect in disordered topological metals.

关键词： topological metal disorder Z2 topological invariant

FHL2 deficiency aggravates candida albicans infec.ion through decreased myelopoiesis

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Science c.ina Life Sciences 2025年

作者： Rongmei Gao Kanchao chen Yimin Wang Rongxia Guo Xiaoyu Zhang Peng Wu Weili Wang Qingxiang Huang Xuemei Xie Shangda Yang Yanling Lü Qian Ren Fei Liu Song chen Fengxia Ma Tao cheng hui cheng State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood Diseases Haihe Laboratory of Cell Ecosystem Institute of Hematology & Blood Diseases Hospital Chinese Academy of Medical Sciences & Peking Union Medical College cAMS center for Stem cell Medicine PUMC Department of Stem Cell and Regenerative Medicine

Hematopoiesis is a finely tuned process that generates all blood cell types through self-renewal and differentiation, which is crucial for maintaining homeostasis. Acute infec.ions can prompt a hematopoietic response known as emergency myelopoiesis. in this study, using a candida albicans (c. albicans) infec.ion model, we demonstrated for the first time that disruption of Fhl2 led to increased fungal burden,heightened inflammatory response and reduced survival rates. impaired myeloid hematopoiesis and immune cell produc.ion were evident, as proved by the decreased numbers of hematopoietic stem and progenitor cells (HSPcs) and granulocytes in the bone marrow of Fhl2-deficient mice. in conclusion, FHL2 regulated emergency myelopoiesis in response to c. albicans, affec.ing the host’s defense against pathogens.

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Formation control with obstacle avoidance of second-order multi-agent systems under directed communication topology

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Science c.ina(information Sciences) 2019年第9期62卷 144-157页

作者： Guoxing WEN c.L.Philip cHEN hui DOU Hongli YANG chunfang LiU college of Science Binzhou University Department of computer and information Science Faculty of Science and Technology University of Macau college of Navigation Dalian Maritime University State Key Laboratory of Management and control for complex Systems Institute of AutomationChinese Academy of Sciences Mathematics and Systems Science college Shandong University of Science and Technology

This paper addresses the obstacle avoidance problem of formation control for the multi-agent systems modeled by double integrator dynamics under a directed interconnec.ion topology. The control task is finished by a leader-follower formation scheme combined with an artificial potential field(APF) *** leader-follower scheme is carried out by taking the desired trajectory with the desired velocity as virtual leader, while the APF method is carried out by dealing with the obstacles as the high potential points. When the obstacle avoidance tasks are finished, the artificial potential forces degrade the formation performance, so their undesired effects are treated as disturbances, which is analyzed by the robust H∞performance. Based on Lyapunov stability theory, it is proved that the proposed formation approach can realize the control objec.ive. The result is also extended to the switc.ing multi-agent formation. The effec.iveness of the proposed formation scheme is further confirmed by simulation studies.

关键词： formation control obstacle avoidance artificial potential field method H_∞ performance second-order multi-agent system directed topology

Fibrous TiO_2 prepared by chemical vapor deposition using ac.ivated carbon fibers as template via adsorption,hydrolysis and calcinations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 981-987页

作者： hui-na YANG Li-fen LiU Feng-lin YANG Jimmy c. YU School of chemical Engineering Dalian University of Technology Dalian 116023 China School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116023 China Department of chemistry the c.inese University of Hong Kong Hong Kong China

TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APcVD （chemical vapor deposition under atmospheric pressure） reactor at ≤200 ℃. Ac.ivated carbon fibers （AcFs） were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron micros- copy （SEM）, transmission electron microscopy （TEM）, Brunauer, Emmett and Teller （BET） and X-ray diffrac.ion （XRD） analysis The pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m^2/g and 148 m^2/g for samples deposited at 100 ℃ and 200℃ （using Ac.i700 as template）, respec.ively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds.

关键词： chemical vapor deposition (cVD) Porous material Ac.ivated carbon fiber (AcF)

High-Performance inTiZnO Thin-Film Transistors Deposited by Magnetron Sputtering

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c.inese Physics Letters 2013年第12期30卷 126-129页

作者： LiU Ao LiU Guo-Xia SHAN Fu-Kai ZHU hui-hui B.c.Shin W.J.Lee c.R.cho college of Physics Science Qingdao UniversityQingdao 266071 Lab of New Fiber Materials and Modern Textile Growing Base for State Key LaboratoryQingdao UniversityQingdao 266071 Electronic ceramics center DongEui UniversityBusan 614714South Korea college of Nanoscience and Nanotechnology Pusan National UniversityBusan 609735South Korea

inTiZnO thin-film transistors(iTZO TFTs)with Al_(2)O_(3)gate dielectrics are fabricated by magnetron sputtering at room *** bottom-gate-type iTZO TFTs with amorphous Al_(2)O_(3)gate dielectrics are operated in the enhancement mode and exhibit a mobility of 50.4 cm^(2)/V·s,threshold voltage of 1.2 V,subthreshold swing of 94.5 mV/decade,and on/off-current ratio of 7×10^(6).We believe that iTZO deposited at room temperature is an appropriate semiconductor material to produce high-mobility TFTs for developing flexible electronic devices.

关键词： temperature mobility film

Effects of alloying elements X( X = Zr,V,cr,Mn,Mo,W,Nb,Y) on ferrite/Tic heterogeneous nucleation interface: first-principles study

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Journal of iron and Steel Research international 2017年第3期24卷 328-334页

作者： hui-hui Xiong Heng-hua Zhang hui-ning Zhang Yang Zhou State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and EngineeringShanghai University School of Metallurgy and chemical Engineering Jiangxi University of Science and Technology

The segregation behavior of alloying elements X（ X = Zr,V,cr,Mn,Mo,W,Nb,Y） on the ferrite（ 100） /Tic（ 100） interface has been investigated using first principles method,and the work of separation and interface energy of ferrite / Tic.interfaces alloyed by these elements were also analyzed. The results indicated that all these alloying additives except Y were thermodynamically favorable because of the negative segregation energy,showing that they have the tendency to segregate to the ferrite / Tic.interface. When the Fe atom in the ferrite /Tic.interface is replaced by Y,Zr,or Nb,the adhesive strength of the interface will be weakened due to the lower separation work,larger interfacial energy,and weaker electron effects. However,the introduc.ion of cr,Mo,W,Mn and V will improve the stability of the ferrite / Tic.interface through strong interac.ion between these elements and c,and cr-doped interface is the most stable structure. Therefore,the cr,Mo,W,Mn and V in ferrite side of the interface can effec.ively promote ferrite heterogeneous nucleation on Tic surface to form fine ferrite grain.

关键词： Fe/Tic.interface Alloying element Heterogeneous nucleation Segregation First-principles

First-principles study on stability, electronic, and mechanical properties of La-c and ce-c binary compounds

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Journal of iron and Steel Research international 2019年第7期26卷 771-778页

作者： hui-ning Zhang Qiu-yan Wu Zhen-ying Hu hui Li hui-hui Xiong An-jun Xu School of Metallurgy and chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 Jiangxi China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology Wuhan 430081 Hubei China Hubei Provincial Key Laboratory for New Processes of iron making and Steelmaking Wuhan University of Science and Technology Wuhan 430081 Hubei China Ganhua Security Technology co. Ltd. Nanchang 330001 Jiangxi China c.ina Metallurgical Planning Net Beijing 100711 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The phase stability and electronic and mechanical properties of rare earth (RE) carbides (La2c3, Lac2, ce2c3, cec2, and cec) were investigated using first-principles calculations based on density func.ional theory. The calculated equilibrium lattice constants and cell volume agree well with available experimental data. The cohesive energy and formation enthalpy of these carbides show that they are thermodynamically and mechanically stable except Lac. The strong covalent bonding exists in these compounds, and the covalent bonds are mainly determined to be RE-c and c-c bonds. The hardness of RExcy compounds is less than 10 GPa, and the bulk modulus, shear modulus, and Young's modulus of ce2c3 are the largest. The values of BiG (ratio of bulk modulus to shear modulus) and Poisson's ratio indicate that all the compounds have good duc.ility, and the duc.ility of cec.is larger than others. The Debye temperature of ce2c3 is 429.67 K, which is the highest in those of experimental compounds.

关键词： Rare earth carbide Electronic structure Mechanical property First principle