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Fractal Growth of Giant Amphiphiles in Langmuir-Blodgett Films

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Chinese Journal of Polymer Science 2022年第6期40卷 556-566页

作者： Wei-Jie Wang Xian xu Yu Shao jian-wen Liao Han-Xin jian Bing xue Shu-Guang Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low-dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Fractal structures have attracted considerable scientific interest,and fractal geometry is an effective tool to study the complicated structure and dynamic processes,such as dilation symmetry of disorder structure,percolation,gelation,and metal-insulator ***,we summarized our findings of fractal growth of giant amphiphiles in Langmuir-Blodgett(LB)*** amphiphiles composed of polyhedral oligomeric silsesquioxanes(POSS)derivatives and poly(ethylene oxide)(PEO),with structural diversities of POSS head modification,POSS head number,PEO chain length,are precisely *** effect of molecular structures and operation parameters on the fractal growth patterns are discussed,in addition,other fractal growth patterns in LB films and in Langmuir films are included,aiming to understand the basic molecular principle of fractal growth in LB system.

关键词： Fractal growth Langmuir-Blodgett(LB)film Langmuir film Giant amphiphiles Poly(ethylene oxide)(PEO)crystallization

Finite element simulation of real cavity closure in cast Ti6Al4V alloy during hot isostatic pressing

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China Foundry 2022年第1期19卷 55-62页

作者： Qian xu wen Li Ya-jun Yin jian-xin Zhou Hai Nan State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan 430074China AECC Beijing Institute of Aeronautical Materials Beijing 100095China

The healing behavior of shrinkage cavity inside the cast Ti6Al4V alloy during hot isostatic pressing(HIP)was investigated experimentally by interrupted hot isostatic pressing *** X-ray micro computed tomography was used to record the morphology changes before and after hot isostatic *** two-dimensional geometry obtained by the microCT scan was used in simulation to study the evolution of the real shrinkage cavity during hot isostatic *** cavities,shrinkage porosity and small gas pores can be effectively eliminated under proper HIP *** two-dimensional morphology in the simulation results agrees well with the experimental *** study reveals that plastic deformation,creep and diffusion are the main mechanisms of cavity closure during hot isostatic *** addition,the simplified elliptical pores with aspect ratios at different positions were used to replace the real pores to further study the factors affecting the position of dimples after HIP by *** is found that the position of the dimples mainly depends on the aspect ratio of the elliptical pore and the distance between the pore surface and the external surface of the geometric model.

关键词： cast Ti6Al4V alloy hot isostatic pressing shrinkage cavity simulation closure behavior

Particle agglomeration behavior in fluidized bed during direct reduction of iron oxide by CO/H_(2)mixtures

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Journal of Iron and Steel Research International 2023年第4期30卷 626-634页

作者： Feng Lu Hong Zhong Bo Liu jian xu Sheng-fu Zhang Liang-ying wen School of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China School of Mechanical and Materials Engineering Washington State UniversityPullmanWA 99163USA

The agglomeration behavior of particles significantly impacts on the defluidization occurring in a fluidized bed during the direct reduction *** influence of CO/H_(2)ratio on surface diffusion of iron atoms was proposed,and the solid bridge force between iron oxide particles was quantificationally ***,the solid bridge force was successfully added into a CFD–DEM(computational fluid dynamics–discrete element method)model combined with heat transfer and mass transport to investigate the detailed information of agglomeration in a fluidized bed,including the spatial distribution of temperature,velocity and metallization of iron oxide *** region of defluidization is sensitive to the reduction *** the same reduction temperature,the iron oxide powder will perform higher metallization and stable fluidization properties with molar fraction of H_(2)in the range of 0.6–0.8,when iron oxide is reduced by CO/H_(2)mixture.

关键词： Direct reduction Computational fluid dynamics Discrete element method Particle agglomeration CO/H_(2)mixture Micro morphology

Effects of N-1 substituent on the phototoxicity of fluoroquinolone antibiotics: comparison of pefloxacin and difloxacin

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Nuclear Science and Techniques 2020年第7期31卷 34-45页

作者： jian-Feng Zhao Yan-Cheng Liu Yu-Lie xu wen-Feng Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China

The photophysics and photochemistry of pefloxacin(PEF),a 1-ethyl-substituted fluoroquinolone(FQ)antibiotic,were studied using transient,steady-state experimental methods and computational *** fundamental photoproperties of PEF and its phototoxicity toward lysozyme,a single-chain protein,were compared with those of a 1-fluorophenyl-substituted FQ antibiotic,difloxacin(DIF).The results showed that the phototoxicity was significantly decreased by the insertion of the bulky1-fluorophenyl substituent(the phototoxicity of DIF was approximately one-quarter of that observed for PEF).This trend was attributed to the lowest lying singlet state with sizeable oscillator strength(f C 0.1)being shifted from319 nm in PEF to 266 nm in DIF upon the insertion of the bulky substituent at the 1-position,as investigated by using computational *** addition,95%of the solar UV irradiation that reaches the earth’s surface has wavelength[315 ***,reducing the most effective excitation wavelength by optimizing the substituent at the1-position may be a promising strategy to alleviate the phototoxicity of FQ *** findings may be applied to other FQ antibiotics because a large number of phototoxicity studies on FQ antibiotics with different substituents at the 1-position can prove these finding’s ***,an FQ antibiotic bearing a chlorine and bulky substituent at the 8-and 1-positions,respectively,exhibits no phototoxicity is the most recent example reported to *** the best of our knowledge,this is the first transient and steady-state study of the effect of the N-1 substituent on the photochemistry and phototoxicity of FQ *** findings will be beneficial to the development of novel FQ antibiotics without phototoxicity.

关键词： substituent transient photochemistry

纸塑包装灭菌搁置筐的设计与降低湿包率效果观察

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中国消毒学杂志 2018年第1期35卷 52-54页

作者：展瑞汶徐建文张春志季晓云夏丽丽上海市杨浦区市东医院上海200438 海宁市人民医院同济大学附属杨浦医院杨浦区中医医院

目的观察一种自主研发的纸塑包装灭菌搁置筐在压力蒸汽灭菌应用中降低湿包率的效果。方法对比使用常规灭菌装载筐与应用搁置筐灭菌后发生湿包情况。结果在4所医院观察到用常规灭菌装载筐(对照组)放置纸塑包装器械12 112件,发生湿包1 393... 详细信息

目的观察一种自主研发的纸塑包装灭菌搁置筐在压力蒸汽灭菌应用中降低湿包率的效果。方法对比使用常规灭菌装载筐与应用搁置筐灭菌后发生湿包情况。结果在4所医院观察到用常规灭菌装载筐(对照组)放置纸塑包装器械12 112件,发生湿包1 393件,湿包率为11.50%;用纸塑包装灭菌搁置筐(实验组)放置纸塑包装器械12 112件,发生湿包95件,湿包率为0.78%。两组比较,差异有统计学意义(P<0.001)。结论使用搁置筐可有效降低压力蒸汽灭菌纸塑包装器械的湿包现象。

关键词：纸塑包装器械搁置筐压力蒸汽灭菌湿包

Analysis of non-uniform hetero-gate-dielectric dual-material control gate TFET for suppressing ambipolar nature and improving radio-frequency performance

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Chinese Physics B 2019年第10期28卷 571-578页

作者： Hui-Fang xu jian Cui wen Sun Xin-Feng Han Institute of Electrical and Electronic Engineering Anhui Science and Technology University

A tunnel field-effect transistor(TFET) is proposed by combining various advantages together, such as non-uniform gate-oxide layer, hetero-gate-dielectric(HGD), and dual-material control-gate(DMCG) technology. The effects of the length of non-uniform gate-oxide layer and dual-material control-gate on the on-state, off-state, and ambipolar currents are investigated. In addition, radio-frequency performance is studied in terms of gain bandwidth product, cut-off frequency,transit time, and transconductance frequency product. Moreover, the length of non-uniform gate-oxide layer and dualmaterial control-gate are optimized to improve the on-off current ratio and radio-frequency performances as well as the suppression of ambipolar current. All results demonstrate that the proposed device not only suppresses ambipolar current but also improves radio-frequency performance compared with the conventional DMCG TFET, which makes the proposed device a better application prospect in the advanced integrated circuits.

关键词： non-uniform gate-oxide layer ambipolar current radio-frequency performances tunnel fieldeffect transistor

Penetration performance of W/Cu double-layer shaped charge liners

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Rare Metals 2016年第2期35卷 184-191页

作者： wen-jian Dong Jin-xu Liu Xing-Wang Cheng Shu-Kui Li Qing-He Zou wen-Qi Guo School of Materials Science and Engineering Beijing Institute of Technology Mudanjiang North Alloy Tool Co. Ltd.

Two kinds of W/Cu double-layer shaped charge liner（SCL） were prepared by chemical vapor deposition（CVD） combined with electroforming technique： A SCL with W inner layer and Cu outer layer, B SCL with Cu inner layer and W outer layer. The penetration properties of A and B SCLs were researched. The results show that the two SCLs can form continuous jet and the tip velocities of A and B jets are 7.4 and 6.3 km s^（-1）, respectively. The kinetic energy density（5.3 9 1011 J m-3） of A jet tip increases by 194.4 %compared with that（1.8 9 1011 J m-3） of B jet tip. B jet,however, exhibits deeper penetration depth at the same experimental conditions. The chemical component and microstructure of the area nearby the ballistic perforation were researched. Component analysis shows that both the jets are formed only from inner layer metal. Microstructure analysis shows that martensite and intermetallic form around ballistic perforation penetrated by A SCL due to the intensive interaction between W jet and steel target. The two kinds of newly formed ultrahard phases also hinder the jet from penetrating target further. As a result of relatively alleviative interaction between Cu jet and target, only solid solution rather than ultrahard phases forms around ballistic perforation penetrated by B SCL.

关键词： Shaped charge liner Jet Penetration performance Chemical vapor deposition Electroforming technique

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CPS固载离子液体催化剂的制备及性能研究

现代化工 2025年第1期45卷 195-200页

作者：徐晨霞吕建华刘继东郭豹李文松河北工业大学化工学院过程工业安全研究中心天津300131

采用改性后的聚苯乙烯树脂CPS为载体,制备了CPS固载3种不同离子液体的催化剂;在无助剂条件下催化CO_(2)和环氧丙烷(PO)转化为碳酸丙烯酯(PC)。利用FT-IR、XPS、SEM、TG对不同催化剂进行表征分析,并比较了3种催化剂的催化性能。结果表明,... 详细信息

采用改性后的聚苯乙烯树脂CPS为载体,制备了CPS固载3种不同离子液体的催化剂;在无助剂条件下催化CO_(2)和环氧丙烷(PO)转化为碳酸丙烯酯(PC)。利用FT-IR、XPS、SEM、TG对不同催化剂进行表征分析,并比较了3种催化剂的催化性能。结果表明,CPS-Imi/COOH表现出最好的催化活性,这是由于—COOH通过形成氢键对PO的C—O键具有较强的极化能力;Br^(-)对PO的亲核攻击也是其容易开环的重要因素。考察了不同反应条件下CPS-Imi/COOH对PO转化率和PC选择性的影响,在110℃、2.5 MPa、3 h的反应条件下,PO转化率为95.8%,PC选择性为98.8%;催化剂循环使用6次后仍保持良好的催化性能。

关键词： CPS固载离子液体二氧化碳环氧丙烷碳酸丙烯酯

An analytical method for studying double Hopf bifurcations induced by two delays in nonlinear differential systems

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Science China(Technological Sciences) 2020年第4期63卷 597-602页

作者： GE JuHong xu jian Department of Mathematics and Information Science Henan University of Economics and LawZhengzhou 450046China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China

An analytical method is introduced to investigate double Hopf bifurcations induced by two delays qualitatively and *** an illustrative example,the clear procedure is demonstrated to study delay-induced weak resonant double Hopf bifurcation in a nonlinear system with multiple *** two delays are close to double Hopf bifurcation point,all solutions derived from the bifurcation are classified qualitatively and expressed *** simulations are a good agreement with our theoretical analysis,and also already work in *** results show that our work in this paper proposes a simple and valid method for investigating delay-induced double Hopf *** important feature of our work is that the explicit expression of periodic solutions is easy to be obtained by solving algebraic equations.

关键词： analytical methods multiple delays double Hopf bifurcation the coexistence of periodic motion