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Technique of pulse electrochemical finishing in molds and dies

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 487-492页

作者： LI Hong-you LIU Xiao-mei JIANG Kai-yong wang Hui zhou jin-jin Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China Mould & Die Technology Research Center Huaqiao University Quanzhou 362021 China School of Mechanical Engineering Dalian University of Technology Dalian 116024 China School of Mechanical Engineering Dalian University of Technology Dalian 116024 China

Surface finishing is one of the most important processes in mould and die making. This process is necessary not only for smoothing the surface of die or mould, but also for removing the surface layer, which has been damaged by the preceding machining process and finally improve the performances and lifetime of moulds to a large extent. It has been reported that between 30% and 40% of the total time required to manufacture a die or mold is spent on finishing operations, most of which are performed by skilled workers employing traditional techniques. At present, key problems in mould and die finishing technology can improve the finishing efficiency, consistency and quality at reduced costs. A new and high efficiency unconventional finishing technology, pulse electrochemical finishing was introduced. Experiments were done in neutral nitrate electrolytes. The influence of electrolyte composition, intereletrode gap, finishing time, flow quality, current density, compositions of steel materials and pulse parameters on the resulting surface finishing was investigated. Results indicate that pulse parameters have important influence on operations finishing and the proper selection of pulse parameters can lead to both good smoothing efficiency and surface quality at low costs.

关键词： moulds dies pulse electrochemical finishing surface quality performance lifetime

Effects of the Fabrication Processes of NC-Si:H Films on Their Mechanical Properties

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Chinese Journal of Aeronautics 2006年第B12期19卷 202-205页

作者： LIN jin-zhao wang jin-liang zhou Bo WU Er-xing Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100083 China

Studies of nanoindentation were performed on nc-Si：H films to evaluate the effects of the fabrication processes on their mechanical properties. It is observed that with the decrease of the SiH4 contents, the grain size of the films increases gradually, and as does the crystalline volume fraction. The smaller the grains become, the more homogeneous the films, and the more even the hardness as well as the modulus will be. The hardness and the modulus will increase with the substrate＇s temperature rising. The hardness and the modulus of the nc-Si：H films on the Si substrate prove to be higher than those on the glass substrate given the same technology parameters. How- ever, the films on the glass substrate appear to be more homogeneous.

关键词： nanoindentation hardness modulus plasma-enhanced chemical vapor deposition (PECVD) nc-Si:H

Assessment of the contribution percentage of inherent soil productivity of cultivated land in China

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Journal of Integrative Agriculture 2019年第11期18卷 2619-2627页

作者： wang Shi-chao wang jin-zhou ZHAO Ya-wen REN Yi XU Ming-gang ZHANG Shu-xiang LU Chang-ai National Engineering Laboratory of Farmland Cultivation Technology/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The National Agro-Tech Extension and Service Center Beijing 100125P.R.China

The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field *** is a comprehensive measure of soil *** study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in ***,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values *** contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per *** CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following ***,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of ***,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.

关键词： crop yield inherent soil productivity typical cropping system planting years cropspecies

The efficiency of long-term straw return to sequester organic carbon in Northeast China＇s cropland

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Journal of Integrative Agriculture 2018年第2期17卷 436-448页

作者： wang Shi-chao ZHAO Ya-wen wang jin-zhou ZHU Ping CUI Xian HAN Xiao-zeng XU Ming-gang LU Chang-ai Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land Beijing 100081 P.R.China Jilin Academy of Agricultural Sciences Changchun 130124 P.R.China Heilongjiang Academy of Agricultural Sciences Heihe 164300 P.R.China Northeast Institute of Geography and Agro-ecology Chinese Academy of Sciences Harbin 150081 P.R. China

Black soil is one of the most precious soil resources on earth because it has abundant carbon stocks and a relatively high production capacity. However, decreasing organic matter after land reclamation, and the effects of long-term inputs of organic carbon have made it less fertile black soil in Northeast China. Straw return could be an effective method for improving soil organic carbon（SOC） sequestration in black soils. The objective of this study was to evaluate whether straw return effectively increases SOC sequestration. Long-term field experiments were conducted at three sites in Northeast China with varying latitudes and SOC densities. Study plots were subjected to three treatments： no fertilization（CK）; inorganic fertilization（NPK）; and NPK plus straw return（NPKS）. The results showed that the SOC stocks resulting from NPKS treatment were 4.0 and 5.7% higher than those from NPK treatment at two sites, but straw return did not significantly affect the SOC stocks at the third site. Furthermore, at higher SOC densities, the NPKS treatment resulted in significantly higher soil carbon sequestration rates（CSR） than the NPK treatment. The equilibrium value of the CSR for the NPKS treatment equated to cultivation times of 17, 11, and 8 years at the different sites. Straw return did not significantly increase the SOC stocks in regions with low SOC densities, but did enhance the C pool in regions with high SOC densities. These results show that there is strong regional variation in the effects of straw return on the SOC stocks in black soil in Northeast China. Additional cultivations and fertilization practices should be used when straw return is considered as an approach for the long-term improvement of the soil organic carbon pool.

关键词： soil organic carbon(SOC) SOC stock straw return soil sequestration rate straw-C sequestration efficiency black soil long-term experiments

Beneficial effects of BV2 cell on proliferation and neuron-differentiating of mesenchymal stem cells in the circumstance of injured PC12 cell supernatant

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Neuroscience Bulletin 2006年第4期22卷 221-226页

作者： Xiao-Guang LUO Hong wang jin zhou Rong YAN Zhe WU Chao-Dong ZHANG Qiu-Shuang wang Department of Neurology First affiliated Hospital China Medical University Shenyang 110001 China

Objective The microglias is the representative of immune cells in the brain. It plays dual roles of both repairing and damaging in injured nervous system, and works as an inevitable component of the circumstance of injured neurons. This study was aiming at the effects of the microglias on the biological activities of mesenchymal stem cells （MSCs） in the circumstance of injured neurons. Methods MSCs were obtained by primary culture. We adopted PC12 cells （PC12） and BV2 cells （BV2） to substitute for neurons and microglias, respectively. PC12 were injured by aged Aβ1-40 and the supernatant of the injured PC12 was used to set up the circumstance of injured neurons. Transwells were used for co-culture of BV2 and MSCs, which allowed the independent detection of cells after co-culture. Immunofluorescence was used to identify MSCs and neuron-differentiating cells with CD44 and neuron specific enolase （NSE） staining, respectively. MTT assay was adopted to measure the proliferation. Results In the circumstance of both BV2 presence and injured PC 12 supernatant incubation, either the proliferation or the differentiation of MSCs reached the highest, which seemed to be contradictory, but we gave our explanations. With the BV2 co-culture, the proliferation of MSCs tend to be higher, but the neuron-differentiating MSCs were similar to those incubated without BV2 co-culture either in normal or injured in PC12 supernatant. With the incubation of injured PC12 supernatant, the neuron-differentiating cells were significantly higher than that of control （P 〈 0.05）. Conclusion In the circumstance of injured neurons, microlgias tend to promote the MSCs proliferation. Although not helpful in neuron-differentiating, microglias did not exert any negative effect either.

关键词： microglias mesenchymal stem cells injured neurons proliferation differentiation

Optimization of Rolling Process for Bi(2223)/Ag Superconducting Tapes by a Statistical Method

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Rare Metals 2001年第1期20卷 66-68页

作者： Xuefeng Li, Peiwen Hua, Wenquan wang, Qijian jin, Yiru zhou, Guansen Yuan (General Research Institute for Nonferrous Metals, Beijing 100088, China) 北京有色冶金研究总院北京 100088

Ag-sheathed (Bi,Pb)(2)SoCa(2)Cu(3)O(x) tapes were prepared by the powder-in-tube method. The influences of rolling parameters on superconducting characteristics of Bi(2223)/Ag tapes were analyzed qualitatively with a statistical method. The results demonstrate that roll diameter and reduction per pass significantly influence the properties of Bi(2223)/Ag superconducting tapes while roll speed does less and working friction the least. An optimized rolling process was therefore achieved according to the above results.

关键词： Bi(2223)/Ag multifilamentary tapes rolling process statistical method optimization

Identification of Specific RAPD Markers Linked to Anthracnose Resistant Gene in Native Wild Grapes of China

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Agricultural Sciences in China 2001年第1期 35-39页

作者： wang Xi-ping wang Yue-jin zhou Peng ZHENG Xue-qin College of Horticulture Northwestern Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 College of Horticulture Northwestern Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 National Key Biotechnology Laboratory for Tropical Crops SCATC Haikou 571101 National Key Biotechnology Laboratory for Tropical Crops SCATC Haikou 571101

Randomly amplified polymorphic DNA (RAPD) was employed to detect molecular markers linked to anthracnose ( Spheceloma ampelinum de Bary) resistant gene in the native wild grapes ( Vitis L. ) of China. RAPD marker OPJ13-300 was linked to anthracnose resistant gene using 90-3 cross F1 V. quinquangularis Rehd (shang-24) × V. vinifera (Longyan). The marker was verified in 90-3 cross F1, Chinese wild grapes and V. riparia and European grape cuitivars. This work has provided a solid basis for molecular marker-assisted selection (MAS) to disease resistance and cloning of disease resistant genes.

关键词： The wild grapes China Anthracnose resistance RAPD

Community structure of macrobenthos in coastal water off Rushan, southern Shandong Peninsula, and the relationships with environmental factors

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Acta Oceanologica Sinica 2009年第5期28卷 81-93页

作者： LI Xinzheng LI Baoquan wang Hongfa wang jinbao wang Xiaochen zhou jin HAN Qingxi MA Lin DONG Chao ZHANG Baolin Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

To understand the present actuality of the marine ecosystem in the southern coastal water region of the Shandong Peninsula and the impact of the global change and the human activities to the marine ecosystem of the region, the macrobenthic community structure was researched based on data from 26 sampling stations carried out on four seasonal cruises from December 2006 to November 2007. The data was analyzed using PRIMER 6.0 and SPSS 15.0 software packages. The results showed that 236 macrobenthic species in total were collected from the research region by the field works. Most of the species belong to Polychaeta （76 species）, Mollusca （75） and Crustacea （60）. Of which, 33 species were common species by the four cruises. The dominant species were different among the four seasons, however, the polychaete species Nephtys oligobranchia and Sternaspis scutata were always dominant in the four seasons. The abundances and biomasses of the macrobenthos from the research region were variable in the four seasons. The results of CLUSTER and MDS analysis showed that the similarities of macrobenthic structures among the stations were low, most of the similarities were at about 40% of similarity values, only that of two stations were up to 60%. In accordance with the similarity values of the macrobenthic structures, the 26 stations were clustered as six groups at arbitrary similarity level of 30%. The ABC curve indicated that the marcofauna communities in the research region had not been disturbed distinctly. The results of BIOENV and BVSTEP （Spearman） analysis implied that the concentrations of organic matter in bottom water and heavy metal copper in sediment, water depth and temperature of bottom were the most significant environmental factors to affect the macrobentic community.

关键词： macrobenthos community structure biodiversity South Huanghai Sea Shandong Peninsula Rushan sea area

Hypersensitive Spectrophotometric Determination of Trace Amounts of Tin ( Ⅳ ) with Salicylfluorone and Mixed Surfactants

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Chemical Research in Chinese Universities 1993年第2期9卷 154-160页

作者： XIE Zeng-hong, wang Dong-jin, zhou Xue-ying HU Xian-guo (Department of Chemistry, Fuzhou University, Fuzhou, 350002)

Introduction Since it was found that cetyltrimethylammonium bromide (CTMAB) can increase greatly the sensitivity of the tin (Ⅳ)-pyrocatechol violet (PV) system, the micellar speetrophotometric determination of tin (IV) has been developed extensⅣely. The most widely used acidity dyes are PV and Bromopyrogallol Red (BPR). They have

关键词： Spectrophotometry Tin Salicylfluorone