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Effect of Sequence Structure on Wetting Behaviors of Fluorinated Methacrylate Polymers Based on Perfluorohexylethyl Methacrylate and Stearyl Acrylate

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Chinese Journal of Polymer Science 2017年第9期35卷 1061-1072页

作者： zi-xu gu jun cheng ming-zu zhang jin-lin he 倪沛红 College of Chemistry Chemical Engineering and Materials Science State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis Soochow University Suzhou 215123 China

Due to the non-crystalline properties of short chain perfluoroalkyl groups, using short chain perfluoroalkyl to stabilize low surface free energy polymers has been a challenging task. In this study, we prepare a series of random copolymers poly（perfluorohexylethyl methacrylate）-co-poly（stearyl acrylate）（P13FMA-co-PSA） and block copolymers poly（perfluorohexylethyl methacrylate）-b-poly（stearyl acrylate）（P13FMA-b-PSA）, and systematically investigate the effects of the sequence structure and the content of 13FMA of the fluorinated copolymers on surface free energy and surface reorganization. Static/dynamic contact angle goniometry and water/oil repellency analyses demonstrate that the random polymer P13FMA-co-PSA could not achieve low surface free energy and low surface reorganization at the same time. In contrast, for the block copolymer P13FMA-b-PSA, both low surface free energy and low surface reorganization are acquired simultaneously. The results of X-ray photoelectron spectroscopy （XPS）, dynamic contact angle goniometry and differential scanning calorimetry （DSC） reveal the above-mentioned properties. The consecutive 13FMA segments improve the surface fluorine density, while the consecutive SA chains enhance the crystallinity of the SA segments, and further hinder the surface reorganization of the perfluoroalkyl groups. Therefore, P13FMA-b-PSA exhibits a higher utilization efficiency of fluorine atoms and a better structural stability than P13FMA-co-PSA.

关键词： Surface free energy Surface reorganization Perfluorohexylethyl methacrylate (13FMA) Stearyl acrylate (SA) Water/oil repellency

Shaped charge penetration into high-and ultrahigh-strength Steel-Fiber reactive powder concrete targets

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Defence Technology（防务技术） 2020年第1期16卷 217-224页

作者： Qiang-qiang Xiao Zheng-xiang Huang xudong zu xin Jia Qi-feng Zhu Wei Cai School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing210094China China South Industries Group Corporation Chongqing400039China

Experiments on shaped charge penetration into high and ultrahigh strength steel-fiber reactive powder concrete(RPC) targets were performed in this *** show that the variation of penetration depth and crater diameter with concrete strength is different from that of shaped charge penetration into normal strength concrete(NSC).The crater diameter of RPC is smaller than that of NSC penetrated by the shaped *** jet particles are strongly disturbed and hardly reach the crater bottom because they pass through the narrow channel formed by jet penetration into the *** effects of radial drift velocity and gap effects of jet particles for a shaped charge penetration into RFC target are ***,a theoretical model is presented to describe the penetration of shaped charge into RPC *** the concrete strength increases,the penetration resistance increases and the entrance crater diameter *** the drift velocity and narrow crater channel,the low-velocity jet particles can hardly reach the crater bottom to increase the penetration ***,the narrow channel has a stronger interference to the jet particles with increasing concrete strength;hence,the gap effects must be *** drift velocity and gap effects,which are the same as penetration resistance,also have significant effects during the process of shaped charge penetration into ultrahigh-strength concrete,The crater profiles are calculated through a theoretical model,and the results are in good agreement with the experiments.

关键词： Shaped charge Reactive powder concrete target Penetration Radial drift velocity Gap effects

Naphthalene decomposition in a DC corona radical shower discharge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 71-77页

作者： Ming-jiang NI xu SHEN Xiang GAO zu-liang WU Hao LU State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China College of Environmental Science and Engineering Zhejiang Gongshang University Hangzhou 310015 China Division of Combustion Physics Lund University S-22100 Lund Sweden

The naphthalene decomposition in a corona radical shower discharge (CRS) was investigated, with attention paid to the influences of voltage and initial naphthalene density. The OH emission spectra were investigated so as to know the naphthalene decomposing process. The by-products were analyzed and a decomposing theory in discharge was proposed. The results showed that higher voltage and relative humidity were effective on decomposition. The initial concentration affected the decomposing efficiency of naphthalene. When the initial naphthalene density was 17 mg/m3, the decomposition rate was found to be 70% under 14 kV. The main by-products were carbon dioxide and water. However, a small amount of carbonic oxide, 1,2-ethanediol and acetaldehyde were found due to the incomplete oxidization.

关键词： Naphthalene decomposition Corona Discharge OH radical

Semicontinuity of the Minimal Solution Set Mappings for Parametric Set-Valued Vector Optimization Problems

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Journal of the Operations Research Society of China 2021年第2期9卷 441-454页

作者： xin xu Yang-Dong xu Yue-Ming College of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China

With the help of a level mapping,this paper mainly investigates the semicontinuity of minimal solution set mappings for set-valued vector optimization ***,we introduce a kind of level mapping which generalizes one given in Han and Gong(Optimization 65:1337–1347,2016).Then,we give a sufficient condition for the upper semicontinuity and the lower semicontinuity of the level ***,in terms of the semicontinuity of the level mapping,we establish the upper semicontinuity and the lower semicontinuity of the minimal solution set mapping to parametric setvalued vector optimization problems under the C-Hausdorff continuity instead of the continuity in the sense of Berge.

关键词： Set-valued vector optimization problems Level mapping Solution set mapping Upper semicontinuity Lower semicontinuity

Edge-Fault-Tolerant Edge-Bipancyclicity of Bubble-Sort Graphs

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Acta Mathematica Sinica,English Series 2012年第4期28卷 675-686页

作者： xin Ping xu Min xu Jin JING Jiangsu Institute of Education School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of Education Department of Mathematics University of Science and Technology of China

The bubble-sort graph Bn is a bipartite graph. Kikuchi and Araki [Edge-bipancyclicity and edge-fault-tolerant bipancyclicity of bubble-sort graphs. Information Processing Letters, 100, 52- 59 （2006）] have proved that Bn is edge-bipancyclic for n ≤ 5 and Bn - F is bipancyclic when n ≥ 4 and IFI≤ n - 3. In this paper, we improve this result by showing that for any edge set F of Bn with IFI ≤ n - 3, every edge of Bn - F lies on a cycle of every even length from 6 to n! for n≤ 5 and every edge of Bn - F lies on a cycle of every even length from 8 to n! for n = 4.

关键词： Cycles bipancyclicity fault tolerance bubble-sort graph

Geotechnical centrifuge model tests for explosion cratering and propagation laws of blast wave in sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 335-343页

作者： Yi-kai FAN zu-yu CHEN Xiang-qian LIANG xue-dong ZHANG xin HUANG State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100044 China School of Transportation Science and Engineering Beihang University Beijing 100191 China

This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge *** centrifuge model tests were completed with various ranges of explosive mass,burial depth and centrifuge *** accelerometers were installed to record the acceleration response in *** dimensions of the explosion craters were measured after the *** results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression *** specific function equations were *** results are in general agreement with those obtained by other studies.A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of *** relationship can be conveniently used to predict the cratering effects in *** results also showed that the peak acceleration is a power increasing function of the acceleration *** empirical exponent relation between the proportional peak acceleration and distance is *** propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.

关键词： Centrifuge model tests Explosion Craters Blast waves Sand

RESEARCH ON HYDRODYNAMIC AND WATER QUALITY MODEL FOR TIDAL RIVER NETWORKS

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Journal of Hydrodynamics 2003年第2期15卷 64-70页

作者： xu zu xin, Lu Shi qiang School of Environment Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China School of Environment Science and Engineering State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

Hydrodynamic and water quality model for tidal river network is set up withMIKE11 modeling system, according to the features of tidal river networks in plain area. The modelwas calibrated using the hydrological and water quality data of 1999, and the results show that thesimulated values agree with the measured data very well. This model is used to numerically analyzethe effects of low flow augmentation on hydrodynamic and water quality conditions of Suzhou *** simulation results show that the flow augmentation can increase net discharge of Suzhou Creekand improve its ability of re-aeration; and its concentration of dissolved oxygen in the rivernetworks can also increase correspondingly.

关键词： tidal river network water quality model suzhou creek low flow augmentation

Rayleigh-Enhanced Nondegenerate Four-Wave Mixing

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Chinese Physics Letters 1996年第9期13卷 672-674页

作者： YU zu-he MI xin JIANG Qian Ll Xiao-feng FU Pan-ming Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080

We report a Rayleigh-enhanced nondegenerate four-wave mixing(NFWM)in carbon *** the Rayleigh-enhanced NFWM spectrum a relaxation time of as short as 220fs was deduced.

关键词： Rayleigh relaxation disulfide

Effects of Chronic Stress of Cadmium and Lead on Anatomical Structure of Tobacco Roots

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Agricultural Sciences in China 2011年第12期10卷 1941-1948页

作者： YUAN zu-li XIONG Shu-ping LI Chun-ming MA xin-ming College of Life Science Henan Agricultural University Zhengzhou 450002 P.R. China College of Agronomy Henan Agricultural University Zhengzhou 450002 P.R.China Institute of Economic Crop Research Henan Academy of Agricultural Sciences Zhengzhou 450002 P.R.China College of Information and Management Science Henan Agricultural University Zhengzhou 450002 P.R. China

Cadmium （Cd2＋） is one of the major widespread environmental pollutants, and can cause serious problems to all organisms. Lead （Pb2＋） is another wide spread dangerous heavy metal. Tobacco is a popular growing economic crop in China. Most tobacco growing region soils contain excessive Cd2＋ and Pb2＋. To assess anatomic changes of tobacco roots under Cd2＋, Pb2＋, and Cd2＋＋pb2＋ chronic stress, a pot experiment was carried out in field. The tobacco seedlings with 6 leaves were transplanted to pots in which soil was placed. The amounts of Cd2＋ added to soil were 0, 3, 6, 10, 30, 60, and 100 mg kg-1 dry soil. The amounts of Pb2＋ added to soil were 0, 150, 300, 450, 600, 750, and 1 000 mg kg-1 dry soil. The amounts of Cd2＋＋Pb2＋ added to soil were 0＋0, 3＋150, 6＋300, 10＋450, 30＋600, 60＋750, and 100＋1000 mg kg-1 dry soil. The contents of Cd2＋ and Pb2＋ in root systems were determined by inductively coupled plasma, and the anatomical structure was studied by method of paraffin sectioning. The results revealed that the amounts of exchangeable Cd2＋ and Pb2＋ and carbonate bound Cd2＋ and Pbz＋ in soil increased with the amounts of Cd2＋ and Pb2＋ added to soil, and the contents of both Cd2＋ and Pb1＋ in roots were significantly increased along with stress time and the amounts of Cd2＋ and Pb2＋ added to soil. The growing of tobacco in Cd2＋ and Cd2＋＋Pb2＋ polluted soil for 50, 100, and 150 d resulted in some abnormal extemal morphological and anatomical changes in ripe region of lateral roots. All the abnormal roots had abnormal vascular cylinders, and the ratio of abnormal extemal morphological and anatomical changes of roots positively correlated with the Cd2＋ contents in roots and stress time. While, there were no abnormal external morphological and anatomical changes of roots under Pb2＋ stress. It was suggested that Cd2＋ stress could cause abnormal anatomic changes of roots, but Pb2＋ stress could not.

关键词： tobacco roots Cd2+ Pb2+ stress anatomical structure