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Rare Metals 2021年第1期40卷 156-167页

作者： chang-sheng wang Hua-Dong Fu Jian-Xin Xie Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyBeijing 100083China

By means of isothermal compression at temperatures in the range of 650-900℃and strain rates in the range of 0.001-1 s^(-1),the dynamic recrystallization behavior and microstructural evolution of a Cu-3.28 Ni-0.6 Si-0.22 Zn-0.11 Cr-0.04 P(wt%)alloy designed by a machine learning method were investigated.A semiempirical constitutive equation,processing maps and an average activation energy were *** microstructure under different conditions and the effect of strain rate on the texture of the alloy at 800-900℃were *** results show that the suitable temperature is800-900℃;when the strain is less than 0.4,the appropriate strain rate is 0.01-0.5 s^(-1);and when the strain is greater than 0.4,the appropriate strain rate is below0.05 s^(-1).After deformation at 800℃,the main texture changed from{112}of copper to a uniform distribution with the increase in strain rate,but the sample did not have obvious texture after deformation at 850 and900℃.The above results can provide a reference for the selection of process parameters.

关键词： High-performance copper alloy Hot compression Dynamic recrystallization Processing map Texture evolution

Development and simulation of a gridded thermionic cathode electron gun for a high-energy photon source

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Nuclear Science and Techniques 2023年第3期34卷 73-81页

作者： sheng-chang wang Da-Yong He Cai Meng Jing-Yi Li Zu-sheng Zhou Jin-Dong Liu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

A gridded thermionic cathode electron gun was developed for the linear accelerator of the High Energy Photon Source(HEPS).An electron gun should provide a large maximum bunch charge with a wide adjustable *** satisfy these requirements,the shape of the electrode was optimized using a multi-objective genetic algorithm.A large bunch charge with an adjustable range was achieved using the grid-limited gun,the flow of which was analyzed using 3-D *** electron gun has been manufactured and tested,and the measured data of the grid-limited current and simulation results are compared and discussed in this study.

关键词： Electron gun Multi-objective genetic algorithm Grid CST

Development of RF windows for 650 MHz multibeam klystron

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Nuclear Science and Techniques 2023年第9期34卷 58-68页

作者： sheng-chang wang Zu-sheng Zhou Zhi-Jun Lu Zhi-Qing Liu Shigeki Fukuda Yu Liu Jing-Yi Li Wei-Ming Li National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Kunshan Guo Li Electronic Technology Co. Ltd.Kunshan 215300China High Energy Accelerator Research Organization KEK 1-1 OhoTsukubaIbaraki 305-0801Japan

Radio frequency windows are developed and evaluated for a 650 MHz continuous-wave multibeam ***-pillbox windows with alumina and beryllia disks are designed with an average RF power of CW 400 *** of a cold test and tuning procedures are *** final measured S11 curves under the required bandwidth are less than-32.0 and-26.9 dB for alumina and beryllia windows,*** windows are tested up to CW 143 kW for traveling waves and CW 110 kW for standing waves using a solid-state amplifier as an RF power *** simulations for windows and benchmark studies for the thermal analysis of ceramic disks are introduced.

关键词： RF window High-power test MBK

Influence of Dog-Bone Apex on Shape During Slab Horizontal Rolling Process

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Journal of Iron and Steel Research International 2007年第3期14卷 37-41页

作者： YU Hai-liang LIU Xiang-hua LI chang-sheng wang Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss and the lost width at slab head and tail were analyzed. The results show that with the increase in the apical dislocation of dog-bone （LA）, the slab spread and the minimum crop end loss at slab head and tail decrease, while the lost width at slab head and tail increases. Meanwhile, the relationships of S/LA-LA, LH/LA-LA, WH/LA-LA, L T/LA- LA, and W T/LA-LA were obtained.

关键词： dog-bone apical dislocation horizontal rolling FEM

Neurotoxicity of tetramethylammonium ion on larval and juvenile zebrafish:Effects on neurobehaviors and multiple biomarkers

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Journal of Environmental Sciences 2024年第9期143卷 138-147页

作者： Ruixin Zhang Rui wang Jiajun chang GDaniel sheng Daqiang Yin Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Tetramethylammonium hydroxide(TMAH)is an important compound that utilized and released by the rapidly expanding semiconductor industry,which could hardly be removed by the conventional wastewater treatment *** a cholinergic agonist,the tetramethylammonium ion(TMA^(+))has been reported to induce toxicity to muscular and respiratory systems of mammals and human,however the toxicity on aquatic biota remains poorly *** investigated the neurotoxic effects of TMA^(+)exposure on zebrafish,based on neurobehavior tests and a series of *** inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L,and significant alterations on swimming path angles(straight and deflective movements)occurred even at 10 mg/*** tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species(ROS)and malondialdehyde(MDA),significantly negatively related with the activities of antioxidant enzymes,but not significantly correlated with the level of acetylcholinesterase(AChE).Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress,rather than the alterations of *** the highest exposure concentration(200 mg/L),TMA^(+)evoked more severe toxicity on zebrafish juveniles,showing significantly stronger elevation on the MDA activity,and greater inhibitions on the activities of antioxidant enzymes and ACh E,suggesting juveniles were more susceptible to TMA^(+)exposure than larval zebrafish.

关键词： Tetramethylammonium Zebrafish Oxidative stress Acetylcholinesterase Neurobehavior

Molecular Chaperone-Dependent Polymer Translocation through Nanopores: The Effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： chang-sheng Zuo Kang wang Li-Zhen Sun Ting-Ting Sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

The effect of phosphate additive on the positive electrolyte stability of vanadium redox flow battery

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Journal of Energy Chemistry 2018年第5期27卷 1376-1380页

作者： Fengyu Tian Lei wang chang-sheng wang School of Chemistry and Chemical Engineering Liaoning Normal University

The electrolyte is one of the most important components of vanadium redox flow battery （VRFB）. and its stability and solubility determines the energy density of a VRFB. The performance of current positive elec- trolyte is limited by the low stability of VO2＋ at a higher temperature. Phosphate is proved to be a very effective additive to improve the stability of VO2＋. Even though, the stabilizing mechanism is still not clear, which hinders the further development of VRFBs. In this paper, to clarify the effect of phosphate additive on the positive electrolyte stability, the hydration structures of VO2＋ cations and the reaction mechanisms of precipitation with or without phosphate in the supporting electrolyte of H_2SO_4 solutions were investigated in detail based on calculations of electronic structure. The stable configurations of com- plexes were optimized at the B3LYP/6-311 ＋ G（d,p） level of theory. The zero-point energies and Gibbs free energies for these complexes were further evaluated at the B3LYP/aug-cc-pVTZ level of theory. It shows that a structure of [VO_2（H_2O）_2]＋ surrounded by water molecules in H2S04 solution can be formed at the room temperature. With the temperature rises, [VO_2（H_2O）_2]＋ will lose a proton and form the interme- diate of VO（OH）_3, and the further dehydration among VO（OH）_3 molecules will create the precipitate of V_2O_5. When H_3PO_4 was added into electrolytes, the V-O-P bond-containing neutral compound could be formed through interaction between VO（OH）_3 and H_3PO_4, and the activation energy of forming the V-O-P bond-containing neutral compound is about 7 kcal tool-1 lower than that of the VO（OH）_3 dehydration, which could avoid the precipitation of V_2O_5 and improve the electrolyte stability.

关键词： All vanadium redox flow battery Phosphate additive Density functional theory Transition state Reaction mechanism

Point-of-care ultrasound for the early diagnosis of emphysematous pyelonephritis: A case report and literature review

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World Journal of Clinical Cases 2021年第11期9卷 2584-2594页

作者： Zhou-Xiong Xing Hang Yang Wen Zhang Yu wang chang-sheng wang Tao Chen Hua-Jun Chen Department of Critical Care Medicine Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina

BACKGROUND Emphysematous pyelonephritis(EPN)is a rare but fatal necrotic infection of the kidney,which usually leads to septic ***,early diagnosis and optimized therapy are of paramount *** the past two decades,pointof-care ultrasound(POCUS)has been widely used in clinical practice,especially in emergency and critical care settings,and helps to rapidly identify the source of infection in *** report a rare case in which a“falls”sign on POCUS played a pivotal role in the early diagnosis of *** SUMMARY A 57-year-old man presented with fever and lumbago for 3 d prior to *** went to the emergency room,and the initial POCUS detected gas bubbles in the hepatorenal space showing a hyperechoic focus with dirty shadowing and comet-tail *** imaging feature was like a mini *** blood and urine culture demonstrated Escherichia coli bacteremia,and EPN associated with septic shock was *** patient did not respond to broad-spectrum antibiotic treatment and a perirenal abscess *** subsequently underwent computed tomography-guided percutaneous catheter drainage,and fully *** also review the literature on the sonographic features of POCUS in *** This case indicates that a“falls”sign on POCUS facilitates the rapid diagnosis of severe EPN at the bedside.

关键词： Emphysematous pyelonephritis Point-of-care ultrasound Ultrasound Urinary

Design and high-power test of 800-kW UHF klystron for CEPC

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Chinese Physics B 2022年第8期31卷 154-159页

作者： Ou-Zheng Xiao Shigeki Fukuda Zu-sheng Zhou Un-Nisa Zaib sheng-chang wang Zhi-Jun Lu Guo-Xi Pei Munawar Iqbal Dong Dong Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China High Energy Accelerator Research Organization KEKOhoIbaraki 305-0801Japan

To reduce the energy demand and operation cost for circular electron positron collider(CEPC), the high efficiency klystrons are being developed at Institute of High Energy Physics, Chinese Academy of Sciences. A 800-k W continuous wave(CW) klystron operating at frequency of 650-MHz has been designed. The results of beam–wave interaction simulation with several different codes are presented. The efficiency is optimized to be 65% with a second harmonic cavity in three-dimensional(3D) particle-in-cell code CST. The effect of cavity frequency error and mismatch load on efficiency of klystron have been investigated. The design and cold test of reentrant cavities are described, which meet the requirements of RF section design. So far, the manufacturing and high-power test of the first klystron prototype have been *** the gun operated at DC voltage of 80 k V and current of 15.4 A, the klystron peak power reached 804 k W with output efficiency of about 65.3% at 40% duty cycle. The 1-d B bandwidth is ±0.8 MHZ. Due to the crack of ceramic window, the CW power achieved about 700 kW. The high-power test results are in good agreement with 3D simulation.

关键词： klystron cavity beam–wave interaction circular electron positron collider(CEPC) high-power test

Prediction of mushy zone permeability of Al-4.5wt%Cu alloy during solidification by phase field model and CFD simulation

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China Foundry 2019年第5期16卷 313-318页

作者： Long-fei Li Rui-jie Zhang Shi-jie Hu Dan Zhang Shi-di Yang chang-sheng wang Hai-tao Jiang University of Science and Technology Beijing Beijing 100083 China Sanying Precision Instruments Company Limited Tianjin 300399 China University of Shanghai for Science and Technology Shanghai 200093 China

Liquid permeability of the mushy zone is important for porosity formation during the solidification process. In order to investigate the permeability of the mushy zone, an integrated model was developed by combining the phase field model and computational fluid dynamics (CFD) model. The three-dimensional multigrain dendrite morphology was obtained by using the phase field model. Subsequently, the computer-aided design (CAD) geometry and mesh were generated based on calculated dendrite morphologies. Finally, the permeability of the dendritic mushy zone was obtained by solving the Navier-Stokes and continuity equations in ANSYS Fluent software. As an example, the dendritic mushy zone permeability of Al-4.5wt%Cu alloy and its relationship with the solid fractions were studied in detail. The predicted permeability data can be input to the solidification model on a greater length scale for macro segregation and porosity simulations.

关键词： phase field model mushy zone computational fluid dynamics permeability solidification