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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu Xiong zhang Xiao-qiang li Peng li Yan-Bin Wang Shuang zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Constructing two-dimensional interfacial ice-like water at room temperature for nanotribology

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Nano Research 2023年第7期16卷 9977-9982页

作者： Yue Hong Deliang zhang Zhiliang Gao Yuge zhang qiang li Mingdong Dong Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China Interdisciplinary Nanoscience Center(iNANO) Aarhus UniversityAarhus C DK-8000Denmark

Water/solid interfaces play crucial roles in a wide range of physicochemical and technological ***,our microscopic understanding of the interfacial water under ambient temperature is relatively ***,we report the direct experimental construction of two-dimensional(2D)ice-like water layer on hydrophilic surface at room temperature by using environment-controlled atomic force *** contrast to the prevailing view that nanoscale confinement is needed for the formation of 2D ice-like water,we find that 2D ice-like water can form on mica surface at temperatures above the freezing point without *** 2D ice-like water layer shows epitaxial relation with the underlying mica lattice and good *** addition,the growth of ice-like water layer can be well controlled by the mechanical force from the scanning ***,the friction properties of 2D ice-like water layer are also probed by friction force *** is found that the icelike water layer can dramatically reduce the *** results provide deep understanding of 2D ice-like water formation on solid surfaces without nanoscale confinement and suggest means of growing 2D ices on surfaces at room temperature.

关键词： two-dimensional ice friction mica surface atomic force microscopy friction force microscopy

Time Optimal Feedrate Generation with Confined Tracking Error Based on linear Programming

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Journal of Systems Science & Complexity 2015年第1期28卷 80-95页

作者： GUO Jianxin zhang qiang GAO Xiao-Shan li Hongbo Academy of Mathematics and Systems Science Chinese Academy of Sciences College of Information and Control Engineering China University of Petroleum(East China)

In this paper,the problem of time optimal feedrate generation under confined feedrate,axis accelerations,and axis tracking errors is *** main contribution is to reduce the tracking error constraint to constraints about the axis velocities and accelerations,when the tracking error satisfies a second order linear ordinary differential *** on this simplification on the tracking error,the original feedrate generation problem is reduced to a new form which can be efficiently solved with linear programming *** results are used to validate the methods.

关键词： CNC machining dynamics linear programming optimal control time optimal feedrate planning tracking error.

Evaluation of four final irrigation protocols for cleaning root canal walls

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International Journal of Oral Science 2020年第3期12卷 269-274页

作者： qiang li Qian zhang Xiaoying Zou lin Yue Department of Cariology Endodontology and Operative DentistrySchool and Hospital of StomatologyPeking UniversityBeijingChina Central Laboratory Peking University School and Hospital of StomatologyBeijingChina

The aim of this study was to compare the efficiency of four final irrigation protocols in smear layer removal and bacterial inhibition in root canal *** roots inoculated with Enterococcus faecalis were prepared with ProTaper Universal *** teeth were disinfected by conventional needle irrigation,sonic agitation using the EndoActivator device,passive ultrasonic irrigation,or an M3 Max *** with no root canal preparation served as blank controls for the establishment of the infection *** with preparation but no final irrigation served as a post-instrumentation *** the final irrigation,the teeth were sectioned in *** half of each tooth was examined by scanning electron microscopy(SEM)to assess smear layer removal using a five-point *** other half was examined by confocal laser scanning microscopy(CLSM)using the liVE/DEAD Backlight bacterial viability kit to evaluate the depth of bacterial survival in dentinal *** analysis revealed no significant difference in smear layer removal throughout the whole canal among the EA,PUI,and M3 Max groups(P>0.05).CLSM revealed that PUI achieved the greatest bacterial inhibition depth in the coronal((174.27±31.63)μm),middle((160.94±37.77)μm),and apical((119.53±28.49)μm)thirds of the canal(all Plity in root canal systems.

关键词： needle walls irrigation

Research on temperature field of non-uniform heat source model in surface grinding by cup wheel

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Advances in Manufacturing 2019年第3期7卷 326-342页

作者： Shi-Jie Dai Xiao-qiang li Hui-Bo zhang State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130People's Republic of China School of Mechanical Engineering Hebei University of TechnologyTianjin 300130People's Republic of China Hebei Key Laboratory of Robot Perception and Human-Robot Interaction Tianjin 300130People's Republic of China

To address the problems of thermal damage to a workpiece surface caused by the instantaneous high temperature during grinding and the difficulty in monitoring temperature in real time,the temperature field in the case of composite surface grinding by a cup wheel is *** order to predict the grinding temperature,considering material removal and grinding force distribution,a nonuniform heat source model with different function distributions in the circumferential and radial directions in the cylindrical coordinate system is first proposed;then,the analytical model is deduced and the numerical model of the temperature field is established based on the heat source *** validation experiments for grinding temperature field are carried out using a high-definition infrared thermal imager and an artificial *** to the temperature field based on the uniform heat source model,the results based on the non-uniform heat source model are in better agreement with the actual temperature field,and the temperature prediction error is reduced from approximately 23% to 6%.Thus,the present study provides a more accurate theoretical basis for preventing bums in cup wheel surface grinding.

关键词： Non-uniform heat source Temperature filed Surface grinding Cup wheel

Two SbX_(5)-based isostructural polar 1D hybrid antimony halides with tunable broadband emission,nonlinear optics,and semiconductor properties

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Science China Chemistry 2021年第12期64卷 2111-2117页

作者： Zhikai Qi Yali Chen Huizhi Gao Fu-qiang zhang Shi-li li Xian-Ming zhang Key Laboratory of Magnetic Molecules&Magnetic Information Materials(Ministry of Education) Institute of Chemistry and CultureSchool of Chemistry and Material ScienceShanxi Normal UniversityLinfen041004China Key Laboratory of Interface Science and Engineering in Advanced Material(Ministry of Education) College of Chemistry and Chemical EngineeringTaiyuan University of TechnologyTaiyuan030024China

Metal halide perovskites based on MX6(M is metal and X is halogen)octahedra have developed into significant materials,extensively used in many fields,such as solid-state lighting,semiconductor,and nonlinear ***,the MX_(5)square pyramid-based hybrid metal halides beyond zero-dimensional(0D)polyhedrons and clusters are rarely ***,we reported two new isostructural hybrid antimony halides,namely(2cepyH)SbCl4(1-Cl)and(2cepyH)SbBr4(2-Br)(2cepy=1-(2-chloroethyl)pyrrolidine),characterized by 1D polar polyanionic chains formed by corner-sharing SbX_(5)tetragonal pyramid *** photoexcitation at 340 nm,1-Cl shows broad,yellow phosphorescence emissions stemming from triplet self-trapped excitons,as proved by its long lifetime(6.85μs)and the temperature dependences of broadband *** our knowledge,this should be the first observation on the broadband emissive properties in the 1D hybrid metal halide constructed by MX_(5)tetragonal pyramid ***,second harmonic generation measurements show that the nonlinear optical properties of 2-Br(∼3.2×KDP)are superior to that of 1-Cl(∼1.8×KDP).Experimental and calculated data indicate that the bandgap of 1-Cl is larger than that of 2-Br and that the polar inorganic moieties determine their band *** work opens up a new way for constructing broadband emission materials with novel polar frameworks.

关键词： metal halide square pyramid broadband emission second harmonic generation semiconductor

Tearing Toughness of Ductile Metals

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 150-155页

作者： Cui-Hong li Qi-qiang Duan Zhe-Feng zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

A new parameter, i.e., tearing toughness, was employed to characterize the mechanical properties of some ductile metals （Cu, Cu-2 wt% Be, Cu-Al alloys, and some steels） by using three-leg trousers tearing tests. The experi- mental results demonstrate that their tearing toughness is not a physical constant and shows a close relationship with the materials＇ types and microstructures. It can be inferred that the tearing toughness of different ductile metals has their respective variation range, expectantly, and may be represented by the comprehensive mechanical properties of strength and ductility for various ductile materials.

关键词： Ductile metals Strength Ductility Tearing toughness

Long noncoding RNA HAND2-AS1 re duce d the viability of hepatocellular carcinoma via targeting microRNA-300/SOCS5 axis

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Hepatobiliary & Pancreatic Diseases International 2020年第6期19卷 567-574页

作者： Hua-qiang Bi Zhong-Hui li Hui zhang Department of Hepatobiliary Surgery First Affiliated Hospital of Third Military Medical University(Army Medical University)Chongqing 400038China Department of Radiology First Affiliated Hospital of Third Military Medical University(Army Medical University)Chongqing 400038China Department of Vascular Surgery First Affiliated Hospital of Third Military Medical University(Army Medical University)Chongqing 400038China

Background:Hepatocellular carcinoma(HCC)is one of the most prevalent human cancers with high *** non-coding RNA heart and neural crest derivatives expressed 2 anti-sense 1(HAND2-AS1)is down-regulated in several cancers including HCC,yet the precise mechanisms how HAND2-AS1 regulates cell survival in HCC remains poorly ***:The expression levels of HAND2-AS1 and miR-300 were measured using quantitative real-time *** protein levels of suppressor of cytokine signaling 5(SOCS5),Bcl-2,Bax and cleaved caspase-3 were determined by Western *** viability and cell proliferation were assessed using cell counting kit-8 and clone formation assay,*** apoptosis was detected using flow *** interactions between HAND2-AS1 and miR-300,miR-300 and SOCS5 were validated using luciferase reporter ***:HAND2-AS1 was down-regulated in HCC tissues and cell lines,and the expression level of HAND2-AS1 was positively correlated to patient ***2-AS1 over-expression reduced viability and proliferation in HCC *** HAND2-AS1 level induced apoptosis in HCC cells,accompanied with increased Bax and cleaved caspase-3 levels and decreased Bcl-2 *** also validated that HAND2-AS1 acted as a sponge of miR-300,and there was a negative correlation between expression levels of HAND2-AS1 and miR-300 in HCC ***,we found that SOCS5 was a downstream target of *** addition,miR-300 mimics abolished HAND2-AS1-mediated inhibition of cell viability and ***-300 mimics also reversed the HAND2-AS1-induced apoptosis in HCC ***:lncRNA HAND2-AS1 inhibits proliferation in HCC through regulating miR-300/SOCS5 axis.

关键词： Hepatocellular carcinoma Cell survival Heart and neural crest derivatives expressed 2 anti-sense 1 microRNA-300 Suppressor of cytokine signaling 5

Weldability of 1000 MPa Grade Ultra-low Carbon Bainitic Steel

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Journal of Iron and Steel Research International 2016年第7期23卷 705-710页

作者： Qing-mei JIANG Xiao-qiang zhang li-qing CHEN Pipeline Department of China Petroleum Pipeline Engineering Corporation Langfang 065000 Hebei China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China

Maximum hardness test in weld heat-affected zone（HAZ）,oblique Y-groove cracking test and mechanical property test of welding joint of 1 000 MPa grade ultra-low carbon bainitic steel were carried out,so as to research the weldability of the *** results show that the steel has lower cold cracking sensitivity,and preheating temperature of 100 ℃ can help completely eliminate cold cracks,generating good process *** increase of preheating temperature can reduce the hardening degree of heat-affected *** strength of welding joint decreases and hardness reduces when heat inputs increase,and excellent mechanical properties can be obtained when low welding heat inputs are *** lath bainites of different orientations combined with a few granular bainites that effectively split the original coarse austenite grains are the foundation of good properties.

关键词： ultra-low carbon bainitic steel weldability cold cracking microstructure mechanical property

life cycle assessment and economic analysis of HFC-134a production from natural gas compared with oil-based and coal-based production

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Frontiers of Chemical Science and Engineering 2022年第12期16卷 1713-1725页

作者： Suisui zhang Gang li Boyang Bai Luyao qiang Xiaoxun Ma Jingying li School of Chemical Engineering Northwest UniversityXi’an 710069China Chemical Engineering Research Center of the Ministry of Education(MOE)for Advanced Use Technology of Shanbei Energy Xi’an 710069China Shaanxi Research Center of Engineering Technology for Clean Coal Conversion Xi’an 710069China Collaborative Innovation Center for Development of Energy and Chemical Industry in Northern Shaanxi Xi’an 710069China International Scientific and Technological Cooperation Base of the Ministry of Science and Technology(MOST)for Clean Utilization of Hydrocarbon Resources Xi’an 710069China Longdong University Qingyang 745000China

China is the largest producer and consumer of HFC-134a(1,1,1,2-tetrafluoroethane)in the ***-based route is mainly adopted to produce HFC-134a,which suffers from large waste and CO_(2) *** gas is a low-carbon and clean energy resource,and no research has been found on the environment and economy of producing HFC-134a from natural *** this study,CML 2001 method was used to carry out the life cycle assessment of natural gas(partial oxidation)-based and natural gas(plasma cracking)-based routes(abbreviated as gas(O)-based and gas(P)-based routes,respectively),and their environmental performances were compared with coal-based and oil-based ***,considering that China is vigorously promoting the transformation of energy structure,and the application of electric heating equipment to replace fossil-based heating equipment in industrial field,which has a great impact on the environmental performance of the production processes,the authors conducted a scenario *** results showed that the gas(O)-based route had the most favourable environmental ***,the gas(P)-based route had the highest potential for reducing environmental burdens,and its environmental benefit was the most favourable in scenario ***,the economic performance of the gas(P)-based route was significantly better than that of gas(O)-based and coal-based routes.

关键词： life cycle assessment economic performance HFC-134a natural gas oil coal