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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1029-1040页

作者： Li Zhang Wu Zhang ju-hua Zhang Guang-qiang Li School of Materials and Metallurgy Northeastern University School of Materials Science and Engineering Shenyang Ligong University School of Materials and Metallurgy Wuhan University of Science and Technology

The influences of additives on the phase transformation, occurrence state, and the interface of the Ti component in Ti-bearing blast furnace slag were investigated. After oxidation, most of the Ti component in the slag was enriched into the perovskite phase, which served as the Ti-rich phase during the crystallization process. The phase transformation, occurrence state, and the interface of the Ti component were observed to be affected by the addition of different types of agents. During the oxidation process, titanaugite and Ti-rich diopside phases gradually transformed into non-Ti phases（anorthite： CaMgSi2O6 and CaAl2Si2O8） in the form of dendrites or columns, which were observed to be distributed at the surface of the perovskite phase. Several more cracks appeared along the grain boundaries of the perovskite phase after the addition of P2O5, facilitating the liberation of the perovskite phase. Composite additives combining both an acid and a base, such as CaO ＋ CaF2 or P2O5 ＋ CaF2, were used. We observed that the disadvantages of using single additives were successfully overcome.

关键词： blast furnace slag titanium additives phase transformation interfaces

Characterization of silicon microstrip sensors for space astronomy

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Nuclear Science and Techniques 2020年第10期31卷 13-22页

作者： Jia-ju Wei Jian-hua Guo Yi-Ming Hu Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of SciencesNanjing 210023China

Silicon microstrip detectors are widely used in experiments for space *** the detector is assembled,extensive characterization of the silicon microstrip sensors is indispensable and *** work electrically evaluates a series of sensor parameters,including the depletion voltage,bias resistance,metal strip resistance,total leakage current,strip leakage current,coupling capacitance,and interstrip *** methods are used to accurately measure the strip leakage current,and the test results match each other *** measuring the coupling capacitance,we extract the correct value based on a SPICE model and two-port network *** addition,the expression of the measured bias resistance is deduced based on the SPICE model.

关键词： Silicon microstrip sensor Space astronomy Characterization SPICE model

Effect of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron

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Journal of Iron and Steel Research International 2019年第8期26卷 888-897页

作者： hua Zhang Yan-xin Wu Qiu-ju Li Xin Hong State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy and School of Materials Science and Engineering Shanghai University Shanghai 200072 China Jiangsu Yonggang Group Co. Ltd. Zhangjiagang 215628 Jiangsu China Institute of Engineering Technology University of Science and Technology Beijing Beijing 100083 China

The influence of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron was examined. Four kinds of alloyed ductile irons with different matrix structures were produced through an adequate balance of alloying elements. Tensile tests and dry rolling-sliding wear tests were carried out at room temperature. The results show that yield strength and ultimate tensile strength increase, while elongation decreases until the matrix fully becomes pearlite. The lower matrix hardness results in more graphite emerging on the contact surface, which yields the decrease in friction coefficient. Besides, the wear rate decreases with the increase in matrix hardness among alloyed ductile irons except that with full pearlite matrix, the wear performance of which seems to be deteriorated due to poor fracture toughness. The main wear mechanism is delamination under an air-cooling condition. Based on the results of mechanical and wear tests, ductile iron with about 80% pearlite exhibits better wear performance as well as relatively reasonable mechanical properties.

关键词： Ductile iron Microstructure Mechanical property Wear Delamination

Effects of land-use pattern change on rainfall-runoff and runoff-sediment relations:a case study in Zichang watershed of the Loess Plateau of China

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Journal of Environmental Sciences 2004年第3期16卷 436-442页

作者： ZHAOWen-wu FUBo-jie MENGQing-hua ZHANGQiu-ju ZHANGYin-hui KeyLab.ofSystemsEcology ResearchCenterforEco-EnviromnentalSciences.ChineseAcademyofSciences.Beijing100085China InstituteofGeographicalSciencesandNaturalResourcesResearch ChineseAcademyofSciencesBeijing100101China

The purpose of this article is to identify the effect of land use pattern on rainfall runoff and runoff sediment relations in Zichang Watershed of the Loess Plateau. From 1986 to 1997, many farmlands changed into grassland or woodland, especially the farmland in steep slope positions or far away from the river. The change of land use pattern altered the rainfall runoff and runoff sediment relationships, and led to higher slope of trend curves(STCs) of annual rainfall runoff mass curve and runoff sediment mass curve in 1990s than that in 1980s. It is implied that more soil and water loss yielded in 1990s. In order to reduce soil loss, more attentions should be paid to land use pattern and some grass or other herbaceous filter strips should be built along rivers.

关键词： land use rainfall runoff sediment concentration double mass curve slope of trend curve Loess Plateau

Water-Assisted Injection Molding System Based on Water Hydraulic Proportional Control Technique

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 418-427页

作者： ZHOU hua ZHANG Zengmeng GAO yuan＇an YANG huayong The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Jiujiang Branch of 707 Research Institute China Shipbuilding Industry Corporation Jiujiang 332007 China

Water-assisted injection molding（WAIM）, an innovative process to mold plastic parts with hollow sections, is characterized with intermittent, periodic process and large pressure and flow rate variation. Energy savings and injection pressure control can not be .attained based on conventional valve control system. Moreover, the injection water can not be supplied directly by water hydraulic proportional control system. Poor efficiency and control performance are presented by current trial systems, which pressurize injection water by compressed air. In this paper, a novel water hydraulic system is developed applying an accumulator for energy saving. And a new differential pressure control method is proposed by using pressure cylinder and water hydraulic proportional pressure relief valve for back pressure control. Aiming at design of linear controller for injection water pressure regulation, a linear load model is approximately built through computational fluid dynamics（CFD） simulation on two-phase flow cavity filling process with variable temperature and viscosity, and a linear model of pressure control system is built with the load model and linearization of water hydraulic components. According to the simulation, model based feedback is brought forward to compensate the pressure decrease during accumulator discharge and eliminate the derivative element of the system. Meanwhile, the steady-state error can be reduced and the capacity of resisting disturbance can be enhanced, by closed-loop control of load pressure with integral compensation. Through the developed experimental system in the State Key Lab of Fluid Power Transmission and Control, Zhejiang University, China, the static characteristic of the water hydraulic proportional relief valve was tested and output pressure control of the system in Acrylonitrile Butadiene Styrene（ABS） parts molding experiments was also studied. The experiment results show that the dead band and hysteresis of the water hydraulic propo

关键词： water-assisted injection molding water hydraulics proportional pressure control linear control load characteristic

Relationship Between Leaf C/N Ratio and Insecticidal Protein Expression in Bt Cotton as Affected by High Temperature and N Rate

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Journal of Integrative Agriculture 2014年第1期13卷 82-88页

作者： ZHANG Xiang LU Chun-hua CHEN yuan WANG Gui-xia CHEN yuan CHEN De-hua Jiangsu Provincial Key Laboratory of Crops Genetics and Physiology Yangzhou University Yangzhou 225009 P.R.China Department of Soil and Crop Sciences Texas A&M University College Station 77843 USA

Expression of insecticidal protein for transgenic Bacillus thuringiensis （Bt） cotton is unstable and related to nitrogen metabolism. The objective of this study was to investigate the relationship between leaf carbon nitrogen ratio （C/N） and insecticidal efficacy of two Bt cotton cultivars. C/N ratio and Bt protein content were both measured at peak square period and peak boll period respectively under 5-7 d high temperature and different nitrogen fertilizer rates on the Yangzhou University Farm and the Ludong Cotton Farm, China. All plants were grown in field. The results showed that the C/N ratio enhanced slightly and the Bt protein content remained stable at peak square period, but significant increases for the C/N ratio and decreases markedly for the leaf Bt protein concentration were detected at the peak boll period. The similar patterns at the two growth periods were found for the leaf C/N ratio and Bt protein content by different N fertilizer treatments. When nitrogen rate was from 0 to 600 kg ha-l, the C/N ratio was reduced by 0.017 and 0.006 for Sikang 1 and Sikang 3 at peak square period, compared to the 1.350 to 1.143 reduction for Sikang 1 and Sikang 3 at peak boll period, respectively. Correspondingly, the leaf Bt protein contents were bolstered by 2.6-11.8 and 26.9-36.9% at the two different growth periods, respectively. The results suggested that enhanced C/N ratio by high temperature and nitrogen application may result in the reduction of inseetiocidal efficacy in Bt cotton, especially in peak boll period.

关键词： Bt cotton C/N ratio Bt protein insecticidal efficacy

Microstructural characteristics and aging response of Zn-containing Al-Mg-Si-Cu alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 659-664页

作者： yuan-hua Cai Cong Wang Ji-shan Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy （OM）, field emission scanning electron microscopy （FE-SEM）, transmission electron microscopy （TEM）, tensile test, hardness test, and electrical conductivity measurement. It is found that the as-cast A1-Mg-Si-Cu-Zn alloy is composed of coarse dendritic grains, long needle-like ~/5-A1FeSi white intermetallics, and Chinese script-like a-A1FeSi compounds. During high temperature homogenization treatment, only harmful needle-like ^-A1FeSi phase undergoes fragmentation and spheroidizing at its tips, and the destruc- tive needle-like 5-phase does not show any morphological and size changes. Phase transitions from ^-A1FeSi to ^-A1FeSi and from 6-A1FeSi to [3-A1FeSi are also not found. Zn addition improves the aging hardening response during the former aging stage and postpones the peak-aged hardness to a long aging time. In T4 condition, Zn addition does not obviously increase the yield strength and decrease the elongation, but it markedly improves paint-bake hardening response during paint-bake cycle. The addition of 0.5wt% Zn can lead to an increment of 99 MPa in yield strength compared with the value of 69 MPa for the alloy without Zn after paint-bake cycle.

关键词： aluminum alloys zinc hardening mechanical properties microstructure

TOWARDS EXPLORING WHEN AND WHAT PEOPLE REVIEWED FOR THEIR ONLINE SHOPPING EXPERIENCES

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Journal of Systems Science and Systems Engineering 2018年第3期27卷 367-393页

作者： Liangqiang Li hua yuan Yu Qian Peiji Shao School of Management and Economics University of Electronic Science and Technology of China Chengdu 611731 China

Web 2.0 technologies have attracted an increasing number of people with various backgrounds to become active online writers and viewers. As a result, exploring reviewers＇ opinions from a huge number of online reviews has become more important and simultaneously more difficult than ever before. In this paper, we first present a methodological framework to study the ＂purchasing-reviewing＂ behavior dynamics of online customers. Then, we propose a review-to-aspect mapping method to explore reviewers＇ opinions from the massive and sparse online reviews. The analytical and experimental results with real data demonstrate that online customers can be sectioned into groups in accordance with their reviewing behaviors and that people within the same group may have similar reviewing motivations and concerns for an online shopping experience.

关键词： E-commerce online review review dynamics opinion mining

Micromechanical properties of poly(N-isopropylacrylamide)hydrogel microspheres determined using a simple method

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Particuology 2015年第2期13卷 164-172页

作者： Mei yuan Xiaojie ju Rui Xie Wei Wang Liangyin Chu School of Chemical Engineering Sichuan University

Temperature-responsive poly（N-isopropylacrylamide）（PNIPAM） hydrogel microspheres have attracted extensive attention because of their promising diverse biomedical applications. A quantitative understanding of the micromechanical properties of these microspheres is essential for their practical application. Here, we report a simple method for the characterization of the elastic properties of PNIPAM hydrogel microspheres. The results show that PNIPAM hydrogel microspheres exhibit elastic deformation and the obtained force-deformation experimental data fits the Hertz theory well. The moduli of elasticity of the PNIPAM hydrogel microspheres prepared under different conditions were systematically investigated in this work for the first time. The PN1PAM hydrogel microsphere composition significantly affects their micromechanical properties and their temperature sensitivity behavior. PNIPAM hydrogel microspheres with a larger equilibrium volume change have a lower modulus of elasticity. The modulus of elasticity of the PNIPAM hydrogel microspheres at body temperature （37 ℃, above the lower critical solution temperature （LCST） of PNIPAM） is much higher than that at room temperature （25 ℃, below the LCST of PNIPAM） because ofthermo-induced volume shrinkage and an increase in stiffness. These results provide valuable guidance for the design of smart materials for practical biomedical applications. Moreover, the simple microcompression method presented here also provides a versatile way to investigate the micromechanical properties of microscopic biomedical materials.

关键词： Poly(N-isopropylacrylamide) Microspheres Micromechanical properties Modulus of elasticity Temperature-responsive volume change Lower critical solution temperature

The dynamic response and damage models of rebar reinforced polymer slabs subjected to contact and near-field explosions

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Defence Technology（防务技术） 2023年第10期28卷 330-342页

作者： Hao-nan Zhao Hong-yuan Fang Xiao-hua Zhao Yellow River Laboratory Zhengzhou UniversityZhengzhou450001China

Non aqueous reactive polymer materials produced by the reaction of isocyanate and polyol have been widely used in infrastructure construction,which may be subjected to explosion loads during complex service *** blast response of composite materials is a crucial aspect for applications in engineering structures potentially subjected to extreme *** this work,damage caused to rebar reinforced polymer slabs by surface explosive charges was studied experimentally and numerically.A total of 6 field tests were carried out to investigate the performances of the failure modes of rebar reinforced polymer slabs under contact and near-field *** influence of explosive quantity(10-40 g)and stand-off distances(0-20 cm)at the damage modes were *** results show that the failure modes of rebar reinforced polymer slabs under near-field explosion mainly were bending and surface spalling,while under the impact of contact explosion,the failure modes were craters of the top surface,spalling of the bottom surface,and middle ***,a detailed fully coupled model was developed and validated with the test *** influences of explosive quantity and slab thickness on rebar reinforced polymer slabs under contact explosion were *** on this,the calculation formula between breach diameter,explosive quantity,and slab thickness is fitted.

关键词： Reinforced polymer slab Numerical investigations Empirical prediction Damage models