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Microstructure and Tribological Behavior of a TiO_2/hBN Composite Ceramic Coating Formed via Micro-arc Oxidation of Ti–6Al–4V Alloy

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Journal of Materials Science & Technology 2016年第10期32卷 1071-1076页

作者： Ni ao Daoxin liu Shuaixing Wang qing Zhao Xiaohua Zhang Mengmeng Zhang College of Aeronautics Institute of Corrosion and Protection Northwestern Polytechnical University National Defense Key Discipline laboratory of light Alloy Processing Science and Technology Nanchang Hangkong University

A composite coating containing hexagonal boron nitride（hBN） particles and titanium oxide（TiO_2） was formed on the surface of Ti-6Al-4V alloy via micro-arc oxidation（Mao）. The effect of quantity of the hBN-particles added into electrolyte on microstructure, composition, and wear behavior of the resulting composite coatings was investigated. Microstructure, phase composition, and tribological behavior of the resulting Mao coatings were evaluated via scanning electron microscopy, X-ray diffraction, and ball-on-disc abrasive tests. The results reveal that the TiO_2/hBN composite coating consisting of rutile TiO_2, anatase TiO_2, and an hBN phase was less porous than particle-free coating. Furthermore, the presence of hBN particles in the Mao coating produced an improved anti-friction property. The composite coating produced in the electrolyte containing 2 g/l of hBN particles exhibited the best wear *** outer loose layer of the Mao coatings was removed by a mechanical polishing process, which led to a significant improvement in the wear resistance and anti-friction properties of the Mao coatings and highlighted an essential lubricating role of hBN particles in the composite coatings. However, wear mechanism of the Mao coatings was not relevant to the presence of hBN particles, where fatigue wear dominated the anti-fraction properties of the Mao coatings with and without hBN particles.

关键词： Ti-6Al-4V alloy Micro arc oxidation hBN particle Wear

Ecological and Economic Benefits of Vegetation Management Measures in Citrus Orchards on Red Soils

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Pedosphere 2008年第2期18卷 214-221页

作者： SHUI Jian-Guo WANG Qiu-Zhen l.ao gen-qing J. AU J. l. AllARD Institute of Environmental Resources and Soil Fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou 310021 （China） College of Management Zhejiang University Hangzhou 310027 （China） Soil ＆ Fertilizer Station of Wucheng District Jinhua 321000 （China） Syngenta （China） Investment Co. ltd. Shanghai 200041 （China） Syngenta Asia Pacific Pte. ltd. 250 North Bridge Road Singapore 179101 （Singapore）

A three-year experiment was conducted to investigate and compare the economic and ecological benefits of six types of vegetation management measures in citrus orchards of the hilly red soil region of the eastern part of *** vegetation treatments,including tillage without herbicide(clean tillage)and no tillage without herbicide(sod culture) and with herbicide paraquat(paraquat),glyphosate(glyphosate),glyphosate-glyphosate-paraquat(G-G-P),and paraquat- paraquat-glyphosate(P-P-G),were applied in the citrus orchards on a clayey red soil with slopes of 8°and 13°and a sandy soil with slope of 25°.The results showed that the sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments reduced surface runoff by 38.8%,42.5%,18.7%,28.7%,and 37.5%,then the soil-water losses by 55.5%,51.7%,39.9%,46.8%, and 50.0%,and the N,P,and K nutrient losses by 60.3%,50.2%,37.0%,41.8%,and 45.4%,respectively,as compared with the clean tillage *** weed regeneration ratios with the treatments of clean tillage without herbicide,paraquat, glyphosate,G-G-P,and P-P-G were reduced by 55.1%,67.2%,30.3%,36.8%,and 51.2%,respectively,as compared with the sod *** sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments could increase the soil fertility (annual accumulation of N,P,K,and OM)by 7.1%,6.9%,5.3%,6.2%,and 6.6%,respectively,whereas the clean tillage treatment without herbicide reduced soil fertility by 4.4% after the three-year *** citrus fruit yields in the treatments of paraquat,glyphosate,G-G-P,and P-P-G increased by 7%-10%;the soluble solid,total sugar,total acidity,sugar-acid ratio,and single fruit weight of citrus fruits of all treatments except sod culture significantly(P>0.05) exceeded that of the clean tillage *** general,the paraquat treatment showed the best economic and ecological benefits among the six treatments;therefore,it could be regarded as the best available vegetation management measure in citrus orchards of hilly red soil region

关键词： benefits citrus herbicide red soil vegetation management

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HTAP评测基准的评测能力综述

软件学报 2025年第1期36卷 424-445页

作者：翁思扬俞融王清帅胡梓锐倪葎张蓉周烜周傲英徐泉清杨传辉刘维杨攀飞华东师范大学数据科学与工程学院蚂蚁集团OceanBase 工业和信息化部电子第五研究所

对数据库系统即时修改数据的高效实时分析需求推动了数据库系统向同时支持OlTP业务和OlAP业务两种场景的HTAP数据库系统的快速发展.面对众多的HTAP数据库系统,为了推动HTAP数据库系统的公平比较和健康发展,定义和实现相应的评测基准来评... 详细信息

对数据库系统即时修改数据的高效实时分析需求推动了数据库系统向同时支持OlTP业务和OlAP业务两种场景的HTAP数据库系统的快速发展.面对众多的HTAP数据库系统,为了推动HTAP数据库系统的公平比较和健康发展,定义和实现相应的评测基准来评估HTAP数据库系统的新特性至关重要.首先,分析HTAP数据库系统的关键特征并抽象总结HTAP数据库系统实现的关键技术.然后,提炼出HTAP数据库系统的设计难点和构建HTAP评测基准的挑战,并基于此提出HTAP评测基准应考虑的设计维度,包括数据生成、负载生成、评价指标和一致性模型支持性.对比现有HTAP评测基准在设计维度和实现技术上的差异,总结评测基准在不同设计维度上的优劣.此外,运行已公开的典型评测基准,展示并分析它们对HTAP数据库系统关键特征的评测能力以及对不同HTAP数据库系统的横向对比的支持能力.最后,总结对HTAP评测基准的能力需求和未来的一些研究方向,指出语义一致的负载控制和新鲜数据访问度量是HTAP数据库系统评测基准定义的关键问题.

关键词： HTAP评测基准 HTAP数据库系统性能分析新鲜度

Unprecedented C_(19)-diterpenoid alkaloid glycosides from an aqueous extract of“fu zi”:Neoline 14-O-l-arabinosides with four isomeric l-anabinosyls

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Chinese Chemical letters 2017年第8期28卷 1705-1710页

作者： Xian-Hua Meng qing-lan Guo Cheng-gen Zhu Jian-Gong Shi State Key laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicoChinese Academy of Medical Sciences and PekingUnion Medical CollegeBeijing 100050China

Four structurally unprecedented aconitane-type C_（19）-diterpenoid alkaloid glycosides with isomeric arabinosyls, named aconicarmichosides A–D（1–4）, were isolated from an aqueous extract of ＂fu zi＂, the lateral roots of Aconitum carmichaelii. Their structures were determined as neoline 14-O-a-and 14-O-b-l-arabinopyranosides（1 and 2） and 14-O-a-and 14-O-b-l-arabinofuranosides（3 and 4）, by spectroscopic and chemical methods including 2D NMR experiments and acid hydrolysis. Compounds 1–4 represent the first examples of glycosidic diterpenoid alkaloids.

关键词： Aconitum carmichaelii Ranunculaceae Fu zi Aconitane alkaloid glycoside Neoline 14-O-l-arabinoside Aconicarmichosides A–D

Study on the Removal of MIBK from Aqueous Solution by Vacuum Membrane Distillation

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Journal of Central South University 2000年第4期12卷 178-181页

作者： TANG Jian-jun ZHOU Kang-gen ZHANG Qi-xiu lI qing-gang Metallurgical Separation Science and Engineering lab. Central South UniversityChangsha 410083China

Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitably, which not only pollutes working conditions, but also affects the quality of ultimate product. In order to remove MIBK from aqueous solutions, the means of flat vacuum membrane distillation(VMD) is studied in the paper. The area of the membrane used in the study is 0.02 m 2, the initial volume of feed is 2 l, each experiment was conducted over a time period of 60 120 min. The influences of the factors such as temperature(34.8 55.0 ℃); pressure in the permeate side(10.67 14.67 kPa) and feed flow rate(27.8 69.4 ml/s) were experimentally studied. Increasing the temperature or reducing the pressure in the permeate side results in a faster removal of MIBK; however there is a decrease in removal factor β , increasing the feed flow rate results in a faster removal of MIBK and an increase of removal factor β , especially in the range of lower flow rate. The study indicates that the aim of MIBK removal and recycle from dilute aqueous solutions can be achieved by VMD.

关键词： vacuum membrane distillation methyl isobutyl ketone removal

Enzymatic Synthesis of Agmatine by Immobilized Escherichia coli Cells with Arginine Decarboxylase Activity

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Chemical Research in Chinese Universities 2011年第6期27卷 992-995页

作者： ZHANG Wei-guo ZHao gen-hai lIU Jun-zhong lIU Qian JIao qing-cai State Key laboratory of Pharmaceutical Biotechnology School of Life Science Nanjing University Nanjing 210093 P. R. China

A new method for the enzymatic synthesis of agmatine by immobilized Escherichia coli cells with arginine decarboxylase（ADC） activity was established and a series of optimal reaction conditions was set down. The arginine decarboxylase showed the maximum activity when the pyridoxal phosphate（PlP） concentration was 50 mmol/l, pH=7 and 45 °C. The arginine decarboxylase exhibited the maximum production efficiency when the substrate concentration was 100 mmol/l and the reaction time was 15 h. It was also observed that the appropriate concentration of Mg2＋, especially at 0.5 mmol/l promoted the arginine decarboxylase activity; Mn2＋ had little effect on the arginine decarboxylase activity. The inhibition of Cu2＋ and Zn2＋ to the arginine decarboxylase activity was significant. The immobilized cells were continuously used 6 times and the average conversion rate during the six-time usage was 55.6%. The immobilized cells exhibited favourable operational stability. After optimization, the maximally cumulative amount of agmatine could be up to 20 g/l. In addition, this method can also catalyze D,l-arginine to agmatine, leaving the pure optically D-arginine simultaneously. The method has a very important guiding significance to the enzymatic preparation of agmatine.

关键词： Arginine decarboxylase Agmatine Enzymatic resolution Immobilized cell

Effects of Pesticide Applications on the Biochemical Properties of Transgenic cry 2A Rice and the life History Parameters of Nilaparvata lugens Stl (Homptera: Delphacidae)

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Journal of Integrative Agriculture 2013年第9期12卷 1606-1613页

作者： SHI Zhao-peng DU Shang-gen YANG Guo-qing lU Zhen-zhen WU Jin-cai Horticulture and Plant Protection College Yangzhou University

Effects of transgenic Bt rice on non-target pests following pesticide applications plays an important role in evaluating the ecological safety of transgenic rice. Changes of the life history parameters of laboratory population of Nilaparvata lugens feeding on transgenic Bt rice T2A-1 and its parental line cv. MH63 as the control, and the contents of oxalic acid and soluble sugar following three pesticides （triazophos, jinggangmycin and chlorantraniliprole） treatments were investigated in this paper. Results showed that the population parameters of N. lugens and the physiological and biochemical parameters of rice did not differ significantly between T2A-1 and MH63 without pesticide application. But, the emergence rate （ER）, the nymphal number of next generation （NN）, and the index of population trend （IP） on T2A-1 treated with 10 mg l^-1 of triazophos were significantly higher than those on MH63, respectively, while the hatchability （HB） on T2A-1 treated with the three pesticides were obviously lower than those on MH 63. Furthermore, the content of oxalic acid in MH63 treated with 20 mg l-1 triazophos and, 40 and 80 mg l-1 chlorantraniliprole was significantly higher than that in T2A-1, while the content of soluble sugar in T2A-1 treated with 400 mg l-1 jinggangmycin was significantly higher than that in MH63. The results above indicated that triazophos in a low dose could cause a more favor of T2A-1 to population growth of N. lugens compared with MH 63.

关键词： transgenic Bt rice Nilaparvata lugens triazophos jinggangmycin chlorantraniliprole oxalic acid solublesugar

Blue light is more essential than red light for maintaining the activities of photosystem Ⅱ and Ⅰ and photosynthetic electron transport capacity in cucumber leaves

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Journal of Integrative Agriculture 2016年第1期15卷 87-100页

作者： MIao Yan-xiu W ANG Xiao-zhuo G ao li-hong C HEN qing-yun QU Mei Beijing Key laboratory of Growth and Developmental Regulation for Protected Vegetable Crops College of Agriculture and Biotechnology China Agricultural UniversityBeijing 100193P.R.China

Blue and red lights differently regulate leaf photosynthesis. Previous studies indicated that plants under blue light generally exhibit better photosynthetic characteristics than those under red light. However, the regulation mechanism of related photosynthesis characteristics remains largely unclear. Here, four light qualities treatments （300 μmol m-2 s-1） including white fluorescent light （Fl）, blue monochromatic light （B, 440 nm）, red monochromatic light （R, 660 nm）, and a combination of red and blue light （RB, R：B=8：1） were carried out to investigate their effects on the activity of photosystem II （PSII） and photosystem I （PSI）, and photosynthetic electron transport capacity in the leaves of cucumber （Cucumis sativus l.） seedlings. The results showed that compared to the Fl treatment, the R treatment significantly limited electron transport rate in PSII （ETR11） and in PSI （ETR1） by 79.4 and 66.3%, respectively, increased non-light induced non-photochemical quenching in PSII （q^No） and limitation of donor side in PSI （φND） and reduced most JIP-test parameters, suggesting that the R treatment induced suboptimal activity of photosystems and inhibited electron transport from PSII donor side up to PSI. However, these suppressions were effectively alleviated by blue light addition （RB）. Compared with the R treatment, the RB treatment significantly increased ETR, and ETR1 by 176.9 and 127.0%, respectively, promoted photosystems activity and enhanced linear electron transport by elevating electron transport from QA to PSI. The B treatment plants exhibited normal photosystems activity and photosynthetic electron transport capacity similar to that of the Fl treatment. It was concluded that blue light is more essential than red light for normal photosynthesis by mediating photosystems activity and photosynthetic electron transport capacity.

关键词： cucumber photosystem II photosystem I electron transport

Factors in fluencing farmers' participation in crop intensification program in Rwanda

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Journal of Integrative Agriculture 2017年第6期16卷 1406-1416页

作者： Alphonse Nahayo Morris O.Omondi ZHANG Xu-hui lI lian-qing PAN gen-xing Stephen Joseph Institute of Resources Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 P.R. China College of Agriculture Animal Science and Veterinary Medicine University of Rwanda Musanze P. O. Box 210 Rwanda University of New South Wales School of Material Science and Engineering Sydney NSW 2052 Australia

The crop intensification program（CIP）was introduced in Rwanda in 2007 by the Ministry of Agriculture and Animal Resources（MINAGRI）,Rwanda,as a solution to the land fragmentation,low use of agricultural inputs and low access to extension ***,due to the voluntary nature of farmers’participation and their reluctance to participate,this study aimed at assessing the factors that influence their *** were collected from 340 respondents through a household survey in Mayange and Rusarabuye *** statistics and binary logistic regression model were used to analyze the *** show that the factors that significantly influenced the farmers’participation in the CIP include gender,non-farm income,farmland size,farming experience,land acquisition means,market access,trust and agro-ecological *** fact,the non-farm income significantly increased the farmers’decisions to participate in the CIP（P〈0.001）as it eases the financial capital needed to invest in the CIP *** the land acquisition means,the farmers who inherited or bought the land positively and significantly participated in the CIP（P〈0.05）because they had the land tenure ***,the participation in the CIP was hindered by inadequate irrigation and mechanization facilities,lack of farmers’participation in the CIP planning process,inadequate extension services,inadequate agricultural inputs and inadequate post-harvest *** collaboration between farmers,local leaders,extension agents and agricultural service providers as well as the farmers’practical skills in irrigation and mechanization could enhance the participation to the ***,there is a need on the part of policymakers to empower farmers with adequate knowledge on better cropping practices and agricultural technologies through appropriate extension services and bottom-up based program.

关键词： chemical fertilizers crop intensification program extension services improved seeds post-harvest techniques institutional factors socio-economic factors constraints