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Nanotechnology and Precision Engineering 2018年第4期1卷 242-247页

作者： Hongmin pen Jianhua Guo Zizhen Cao Xianchong Wang Zhiguo Wang Tianjin Institute of Aerospace Mechanical and Electrical Equipment Tianjin 300458China Tianjin Long March Technical Equipment Co.Ltd. Tianjin 300462China Guilin University of Aerospace Technology Guilin 541000China

A finite element method based on the cohesive zone model was used to study the micromachining process of nanosized silicon-carbide-particle(SiCp) reinforced aluminum matrix composites. As a hierarchical multiscale simulation method, the parameters for the cohesive zone model were obtained from the stress-displacement curves of the molecular dynamics simulation. The model considers the random properties of the siliconcarbide-particle distribution and the interface of bonding between the silicon carbide particles and the *** machining mechanics was analyzed according to the chip morphology, stress distribution, cutting temperature, and cutting force. The simulation results revealed that the random distribution of nanosized SiCp causes non-uniform interaction between the tool and the reinforcement particles. This deformation mechanics leads to inhomogeneous stress distribution and irregular cutting force variation.

关键词： Multiscale Cohesive zone model Nanosized silicon carbide particles Composite materials Micromachining

A formally verified transformation to unify multiple nested clocks for a Lustre-like language

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Science China(Information Sciences) 2019年第1期62卷 208-210页

作者： Gang SHI Yucheng ZHANG Shu SHANG Shengyuan WANG Yuan DONG pen-Chung YEW Department of Computer Science and Technology Tsinghua University Department of Computer Science and Engineering University of Minnesota

Multiple nested clocks is a major language feature in synchronous data-flow languages such as Lustre [1]. To build a formally verified compiler for such a language, it is a common practice to compile the source program to a C-like program first before compiling it to low-level machine-dependent code using a formally verified backend compiler

关键词： A formally verified transformation to unify multiple nested clocks for a Lustre-like language cycle

Insights into the synergistic promotion of spin polarization over C_(3)N_(5.4) for enhancing cooperative hydrogen evolution and benzylamine oxidation coupling

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Nano Research 2023年第4期16卷 4225-4232页

作者： Qiuchen Wang Xiaoxu Deng Haiyan pen Fei Liu Meiyang Song peng Chen Shuang-Feng Yin Provincial Guizhou Key Laboratory of Green Chemical and Clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China College of Chemistry and Chemical Engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationState Key Laboratory of Chemo/Biosensing and ChemometricsHunan UniversityChangsha 410082China

Polymers are usually restricted on the high exciton binding energies and sluggish electron transfer because of the low dielectric *** spin-polarized electrons is regarded as an attractive strategy,but often confined to the d-orbital ***,the nonmetal P and N elements co-mediated the spin polarization of carbon nitrides(PCN)have been elaborately *** optimized PCN-3 shows an outstanding hydrogen production(22.2 mmol·g^(-1)·h^(-1))coupled with selective benzylamine oxidation without using any solvent and cocatalysts,which is 200 times of original C_(3)N_(4)and superior to the photocatalysts has been reported to *** and theoretical results verified that the spin-orbital coupling of N 2p and P 2p remarkably increased the parallel spin states of charge and reduced the formation of singlet excitons to accelerate exciton dissociation in carbon *** addition,charge separation and surface catalysis can be significantly enhanced by the electron spin polarization of carbon nitride with the parallel arrangement,huge built-in electric field and disturbed electronic *** finding deepens the insight into the charge separation and exciton dissociation in spin polarization,and offers new tactics to develop high-efficiency catalysts.

关键词： spin polarization photocatalysis amine oxidative coupling hydrogen production C_(3)N_(5.4)

Distribution of gas hydrate reservoir in the first production test region of the Shenhu area,South China Sea

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China Geology 2018年第4期1卷 493-504页

作者： Ru-wei Zhang Jing-an Lu pen-fei wen Zeng-gui Kuang Bao-jin Zhang Hua Xue Yun-xia Xu Xi Chen Guangzhou Marine Geological Survey Chtna Geological SurveyGuangzhou 510075China

In May and July of 2017,China Geological Survey (CGS),and Guangzhou Marine Geological Survey (GMGS)carried out a production test of gas hydrate in the Shenhu area of the South China Sea and acquired a breakthrough of two months continuous gas production and nearly 3.1×10^5 m^3 of production. The gas hydrate reservoir in the Shenhu area of China,is mainly composed of fine-grained clay silt with low permeability,and very difficult for exploitation,which is very different from those discovered in the USA,and Canada (both are conglomerate),Japan (generally, coarse sand)and India (fracture-filled gas hydrate).Based on 3D seismic data preserved-amplitude processing and fine imaging,combined with logging-while-drilling (LWD)and core analysis data,this paper discusses the identification and reservoir characterization of gas hydrate orebodies in the Shenhu production test *** also describe the distribution characteristics of the gas hydrate deposits and provided reliable data support for the optimization of the production well *** BSR feature recognition,seismic attribute analysis, model based seismic inversion and gas hydrate reservoir characterization,this paper describes two relatively independent gas hydrate orebodies in the Shenhu area,which are distributed in the north-south strip and tend to be thicker in the middle and thinner at the *** effective thickness of one orebody is bigger but the distribution area is relatively *** model calculation results show that the distribution area of the gas hydrate orebody controlled by W 18/W 19 is about 11.24 km^2,with an average thickness of 19 m and a maximum thickness of 39 m,and the distribution area of the gas hydrate orebody controlled by W11/W17 is about 6.42 km^2,with an average thickness of 26 m and a maximum thickness of 90 m.

关键词： Shenhu area Gas hydrate Production test Reservoir distnbution

Micromagnetism simulation on effects of soft phase size on Nd2Fe14B/α-Fe nanocomposite magnet with soft phase imbedded in hard phase

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Chinese Physics B 2018年第8期27卷 529-534页

作者： Yu-Qing Li Ming Yue Yi pen Hong-Guo Zhang College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

In this study, micromagnetism simulation by using timte dltterence method is cameo out on the Ncl21-el415/a-Fe nanocomposite magnet with soft phase imbedded in hard phase. The effects of soft magnetic phase size （S） on the magnetic properties and magnetic reversal modes are systematically analyzed. As S increases from 1 nm to 48 nm, the remanence （Jr） increases, while the coercivity （Hci） decreases, leading to the result that the magnetic energy prod- uct [（BH）max] first increases slowly, and then decreases rapidly, peaking at S = 24 nm with the （BH）max of 72.9 MGOe （1 MGOe = 7.95775 kJ.m-3）. Besides, with the increase of S, the coercivity mechanism of the nanocomposite magnet changes from nucleation to pinning. Furthermore, by observing the magnetic moment evolution in demagnetization pro- cess, the magnetic reversal of the soft phase in the nanocomposite magnet can be divided into three modes with the increase of S： coherent rotation （S 〈 3 nm）, quasi-coherent rotation （3 nm≤S 〈 36 nm）, and the vortex-like rotation （S ≥36 nm）.

关键词： micromagnetism simulation magnetization dynamics, Nd2Fe14B/a-Fe nanocomposite magnets

Diversity and Dynamics of Soil Free-Living Nematode Populations in a Mediterranean Agroecosystem

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Pedosphere 2005年第2期15卷 204-215页

作者： LIANGwen-Ju I.LAVIAN S.pen-MOURATOV Y.STEINBERGER FacultyofLifeSciences Bar-IlanUniversityRamat-Gan52900（Israel）.／／InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016（China） FacultyofLifeSciences Bar-IlanUniversityRamat-Gan52900（Israel）

To determine the effect of agricultural management on the dynamics and functional diversity of soil nematode communities in a carrot field at Kibbutz Ramat Hakovesh, Israel, soil samples from 0-10 cm and 10-20 cm depths were collected during the growing season of carrot. Indices were used to compare and assess the response of soil free-living nernatode communities to agricultural management. Eighteen nematode families and 20 genera were observed during the growing period, with Cephalobus, Rhabditidae, Aphelenchus, Tylenchus, and Dorylaimus being the dominant genera/families. During the planting, mid-season and post-harvest periods the total number of nematodes at both depths was significantly lower (P < 0.01) in the carrot treatment than in the control plots, while during the harvest period at both depths total nematodes and bacterivores were significantly higher in the treatment plots (P < 0.01). The values of the maturity index (MI) at both depths were found to be significantly lower in the treatment plots than in the control plots during the pre-planting period (P < 0.05). Overall, WI, MI and PPI were found to be more sensitive indicators than other ecological indices for assessing the response of nematode communities to agricultural management in a Mediterranean agroecosystem

关键词： agricultural management carrot-growing season diversity maturity index nematode community

Energy conservation research of dehumidification system for main cable anticorrosion of suspension bridge

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Engineering Sciences 2011年第2期9卷 74-77页

作者： Chen Ce fan Liangkai Feng Zhaoxiang pen Guanzhong Civil and Transportation College Hohai University Nanjing 210098 China Jiangsu Provincial Yangtze River Highway Bridge Construction Commanding Department （JPCD） Taizhou Jiangsu 225321 China PLA University of Science and Technology Nanjing 210007 China

The necessity of the main cable anticorrosion for suspension bridge is described, and operating principles and composition of main cable dehumidification system are analyzed. An idea using the waste heat of high temperature outlet air of dehumidification system to heat up regeneration air of rotary-type dehumidifier is put forward in this paper. The concrete scheme is to install a heat exchanger on air-out pipeline of roots blower and air-in pipeline of regeneration electric heater of rotary dehumidifier. Air preheated by the heat exchanger enters regeneration electric heater of rotary-type dehumidifier. Energy conservation of main cable dehumidification system for the Yangtze River highway bridge is calculated, and the results show that energy conservation rate can reach 44 %.

关键词： suspension bridge main cable dehumidification system heat exchanger energy conservation

ZnO-chitosan/Rectorite Nanocomposite Exhibiting High Photocatalytic Activities under Visible-light Irradiation

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 310-319页

作者： LI Shiqian pen-Chi Chiang DING Ling Kinjal JShah CHEN Qinghua CHEN Sheng College of Ocean and Bio-chemical Engineering Fujian provincial Key Lab of Coastal Basin EnvironmentFuqing Branch of Fujian Normal UniversityFuqing 350300China Graduate Institute of Environmental Engineering National Taiwan UniversityTaipei City 10673TaiwanChina College of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China College of Urban Construction Nanjing Tech UniversityNanjing 211800China Engineering Research Center of Polymer Green Recycling Ministry of Education(Fujian Normal University)Fuzhou 350007China

Chitosan(CS),hydrated zinc acetate,and rectorite(REC) were used as raw materials to prepare CS-embedded zinc oxide(ZnO) nanoparticle by a chemical precipitation ***-bonded REC-loaded ZnO-CS nanoparticle was to form ZnO-CS/REC nanocomposite photocatalyst,its morphology and structure were analyzed by means of FTIR,XRD,TGA,SEM,and *** effects of the catalyst dosage,methyl orange(MO) initial concentration and solution pH on photocatalytic performance were also *** experimental results show that the ZnO-CS/REC nanocomposite has a particle size of 100 nm with good dispersion and *** irradiation of visible light,0.6 g/L photocatalyst was used to degrade MO in solution for 90 min at pH 6,then the MO solution(10 mg/L) was decolored by more than 99%,indicating that the ZnO-CS/REC nanocomposite exhibited highly photocatalytic degradation ***,the photodegradation kinetic mechanism of MO in aqueous solution is presumed.

关键词： ZnO-Chitosan/rectorite nanocomposite visible-light methyl orange photodegradation

Hybrid Hydrogels Toughened by Chemical Covalent Bonding and Physical Electrostatic Interactions

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Chemical Research in Chinese Universities 2018年第3期34卷 500-505页

作者： LIU Li PAN Ge WANG Licheng pen Xiuyan ZHANG Xinyue WU Guangfeng School of Chemical Engineering Changchun University of Technology Changehun 130012 P. R. China College of Chemistry Jilin University Changchun 130012 P. R. China

Polystyrene nanoparticles with negative charges（n-PSs） were synthesized using styrene（St） and sodium styrene sulfonate（NaSS） as initial materials by surfactant-free emulsion polymerization. Subsequently, a hybrid hydrogel was prepared using acrylamide（AAm） and methacryloyloxyethyltrimethyl ammonium chloride（DMC） as co-monomers with N,N＇-methylenebisacrylmnide（MBA） as a chemical crosslinker and n-PSs as a physical electrostatic interaction agent. The resulting hybrid hydrogels exhibited excellent tensile strength and elongation at break. The tensile stress of hybrid hydrogels was seven times greater than that ofhydrogels without n-PSs. The elongation at break of hydrogels reached 700%, which was much higher compared to those of the hydrogels without n-PSs. Furthermore, swelling measurements of the hydrogels indicate that there is an overshoot in the swelling process and the extent of overshoot decreases with the increasing n-PSs. Therefore, the work presented here provides a method for improving the mechanical properties of hydrogels via the introduction of polymeric nanoparticles.

关键词： Hydrogel Electrostatic interaction Mechanical property Swelling property

Effect of Different Initial pH on the Storage Characteristics and Shelf Life of Liquid Diet for Suckling and Weanling Piglets

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Journal of Integrative Agriculture 2014年第1期13卷 134-139页

作者： HE Yu-yong MA pen LIU Xiao-lan WANG Ren-hua LU Wei College of Animal Science and Technology Jiangxi Agricultural University

An experiment was conducted to investigate the effect of different initial pH on the storage characteristics and shelf life of liquid diet. 45 polypropylene bags were allotted to treatments 1, 2 and 3 on average, 100 g diet and 200 g water were placed into each polypropylene bag, food-grade DL-lactic acid was added to each bag at a rate of 0.0 mL in treatment l, 1.2 mL in treatment 2 and 4.7 mL in treatment 3, air was artificially expelled from each bag prior to heat-sealing. All bags were placed into a cage, cooked with steam at 90~C for 30 rain under normal pressure, then taken out and stored from day 0 to 60 at room temperature. Results indicated that liquid diet in treatment 3 achieved the highest total sensory scores, the pH value had a tendency to decrease and the bacteria count had a tendency to increase in the liquid diet with the advancing of storage time with the advancing of storage time, lowering the initial pH of liquid diet decreased the bacteria count, the AFBl and ZEN concentrations and increased the starch gelatinization degree from day 30 to 60, liquid diet in treatment 3 had a lower （P〈0.01） bacteria count and a higher （P〈0.05） starch gelatinization degree at day 30 and 45 than liquid diet in treatment 1. In conclusion, lowering the initial pH of liquid diet with lactic acid to pH 4 could effectively improve the storage characteristics and shelf life of liquid diet.

关键词： initial pH storage characteristics shelf life liquid diet lactic acid