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Electroless plating of Ni-Zn(Fe)-P alloy on carbon steel sheets

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中国有色金属学会会刊：英文版 2004年第z1期14卷 157-161页

作者： WANG Sen-lin WU hui-huang College of Materials Science and Engineering Huaqiao University Quanzhou 362021 China State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen University Xiamen 361005 China State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen University Xiamen 361005 China

The autocatalytic deposition of Ni-Zn(Fe)-P alloys were carried out on carbon steel sheets from bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and mole ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposit were studied. It is found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the mole fraction of zinc in the deposits never reaches high value, which is less than 18.0%. The structure and surface morphology of Ni-Zn(Fe)-P coatings were charactered by XRD and SEM. The alloys plated at all conditions consist of amorphous phase coexisting with a crystalline cubic Ni phase. The surface morphology of coating is dependent on the deposition parameters.

关键词： electroless plating nickel zinc

Microanalysis on the Hydrogen Ion Irradiated 50 wt pct TiC-C Films

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Journal of Materials Science & Technology 2007年第1期23卷 127-130页

作者： hui JIANG Yaoguang LIU Ningkang huang Key Laboratory for Radiation Physics and Technology of Education Ministry of China Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

The 50 wt pct TiC-C films were prepared on stainless steel substrates by using a technique of ion beam mixing. These films were irradiated by hydrogen ion beam with a dose of 1×10^18 ions/cm^2 and an energy of 5 keV. Microanalysis of X-ray photoelectron spectroscopy （XPS） and secondary ion mass spectroscopy （SIMS） were used to analyze the films before and after hydrogen ion irradiation and to study the mechanism of hydrogen resistance.

关键词： Titanium carbide Hydrogen ion irradiation Microanalysis

Bioinspired zinc-mediated umpolung thiolation of alkyl electrophiles: reaction development, scope and mechanism

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Science China Chemistry 2024年第3期67卷 898-907页

作者： Yuenian Xu Yan Zhang Yong Liu Wen-Wu Sun Jie huang hui He Yingjie Wu Wen Liu Shao-Fei Ni Xu-qiong Xiao Xinxin Shao College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province Shantou UniversityShantou 515063China

Zinc-promoted umpolung thiolation of alkyl electrophiles with masked sulfur transfer reagents in the absence of nickel or copper catalysis is described. This protocol proceeds via a SET process of Zn to electrophilic sulfur reagent followed by insertion of Zn into disulfide and nucleophilic thiolation, providing straightforward access to a wide range of alkyl sulfides with broad substrate scope. A neutral TMEDA-ligated four-coordinated zinc thiolate with tetrahedra geometry was synthesized, isolated and fully characterized by NMR, IR and X-ray analysis. More importantly, the chemical reactivity of this active intermediate has been investigated, enabling the construction of C-Se, C-Te, Sb-S and Bi-S bonds to prepare valuable sulfur-containing molecules and beyond.

关键词： umpolung thiolation C(sp^(3))-S bond formation masked sulfur reagents reductive coupling

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Aboveground biomass and nutrient allocation in an age-sequence of Larix olgensis plantations

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Journal of Forestry Research 2011年第1期22卷 71-76页

作者： ZHAO qiong LIU Xing-yu ZENG De-hui Institute of Applied Ecology Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 P. R. China.

Biomass and nutrient （N, P, K, Ca, Mg） stock in various aboveground tree components （stemwood, stembark, branches and leaves） were quantified in an age sequence of pure Larix olgensis plantations （20, 35, 53 and 69 years old） in Northeast China. The results show that the aboveground biomass allocation in various tree components was in the order of stemwood （62%-83%）, branches （9%-21%）, stembark （7%-11%） and leaves （1%-6%） for all stands. The proportion of stemwood biomass to total aboveground biomass increased whereas that of other tree components decreased consistently with stand age from 20 to 53 years old, but kept relatively constant with stand age from 53 and 69 years old. The nutrient allocation in various tree components generally followed the same pattern as the biomass allocation （i.e. stemwood 〉 branches 〉 stembark 〉 leaves）. The proportion of nutrient stock in leaves to total aboveground nutrient stock decreased consistently with increasing stand age, while that in stemwood increased with stand age from 20 to 53 years old but then decreased from 53 to 69 years old. The rate of nutrient removal for stands was estimated at different stand ages under different logging schemes, showing that the rate of nutrient removal would be unchanged when the rotation length was shortened to 20 years by the harvest of stem only, but greatly increased by the harvest of total aboveground biomass. The rate of nutrient removal would be a considerable reduction for all elements by debarking, especially for Ca.

关键词： Larix olgensis nutrient allocation stand development nutrient removal

Advances in Valveless Piezoelectric Pump with Cone-shaped Tubes

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 766-781页

作者： Jian-hui Zhang Ying Wang Jun huang College of Mechanical and Electrical Engineering Guangzhou University Guangzhou 510006 China College of Mechanical and Electrical Technology Taizhou Polytechnic College Taizhou 225300 China Research Center of Fluid Machinery Engineering andTechnology Jiangsu University Zhenjiang 212013 China

This paper reviews the development of valve- less piezoelectric pump with cone-shaped tube chrono- logically, which have widely potential application in biomedicine and micro-electro-mechanical systems because of its novel principles and deduces the research direction in the future. Firstly, the history of valveless piezoelectric pumps with cone-shaped tubes is reviewed and these pumps are classified into the following types： single pump with solid structure or plane structure, and combined pump with parallel structure or series structure. Furthermore, the function of each type of cone-shaped tubes and pump structures are analyzed, and new direc- tions of potential expansion of valveless piezoelectric pumps with cone-shaped tubes are summarized and deduced. The historical argument, which is provided by the literatures, that for a valveless piezoelectric pump with cone-shaped tubes, cone angle determines the flow resistance and the flow resistance determines the flow direction. The argument is discussed in the reviewed pumps one by one, and proved to be convincing. Finally, it is deduced that bionics is pivotal in the development of valveless piezoelectric pump with cone-shaped tubes fromthe perspective of evolution of biological structure. This paper summarizes the current valveless piezoelectric pumps with cone-shaped tubes and points out the future development, which may provide guidance for the research of piezoelectric actuators.

关键词： Piezoelectric pump Valveless Cone-shapedtube Bionics

Research on Inheritance and Innovation of Children's Folk Sports Culture in the Junction Area Between Chongqing and Hubei

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Contemporary Social Sciences 2023年第2期8卷 146-155页

作者： huang Shanying Ye qiong Xiang Hulin School of Physical Education Chongqing Preschool Education CollegeWanzhou DistrictChongqing Municipality404047

This paper examines the current status and development dilemma of the children’s folk sports culture in the junction area between Chongqing and Hubei with reference to relevant *** the literature review and summary,the study finds there are several factors restricting the inheritance and development of the children’s folk sports culture in the area,including insufficiency of theoretical analysis,weak public support in cities,blind imitation of modern sports culture,and absence of policy *** address the above problems,we put forward several suggestions to promote the inheritance and development of children’s folk sports game ***,we should focus on the theoretical research and cultural dissemination of children’s folk sports ***,we should improve the basic rules of children’s folk sports ***,importance should be attached to government support in developing children’s folk sports game ***,we should ensure the continuation and inheritance of children’s folk sports culture via school ***,we should carry forward children’s folk sports culture and explore ways to develop excellent cultural tourism.

关键词： children folk sports cultural inheritance junction area between Chongqing and Hubei

A NOTE FOR ANALYSIS OF THERMOMECHANICAL CONTACT PROBLEMS

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Acta Mechanica Solida Sinica 2002年第4期15卷 303-311页

作者： Zhang Hongwu huang hui Dalian Univ Technol Dept Engn Mech State Key Lab Struct Anal Ind Equipment Dalian 116024 Peoples R China

A discussion about the bifurcation and non-uniqueness of solutions in theanalysis of thermo-mechanical contact problems with initial gap is given. Without loss ofgenerality, a mechanical contact problem coupled with steady heat transfer is studied and an exampleof non-uniqueness of solutions caused by the thermo-mechanical mechanism is presented. Theimportant work is that the non-uniqueness of solutions, which is different from that found in theanalysis of the traditional frictional contact problems, is studied in detail. The possibleoscillation and non-convergence problems in the iteration process of the numerical computation arediscussed, and an enhanced algorithm is put forward to overcome the difficulties.

关键词： heat transfer contact analysis non-uniqueness of solutions

Effects of substituting chemical fertilizers with manure on rice yield and soil labile nitrogen in paddy fields of China: A meta-analysis

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Pedosphere 2023年第1期33卷 172-184页

作者： qiong HOU Yuemin NI Shan huang Ting ZUO Jian WANG Wuzhong NI College of Environmental and Resource Sciences Zhejiang UniversityZhejiang Provincial Key Laboratory of Agricultural Resources and EnvironmentHangzhou 310058China Agricultural Experimental Station Zhejiang UniversityHangzhou 310058China

Substituting chemical fertilizers with manure is an important method for efficient nutrient management in rice cropping systems of *** nitrogen(N)is the most active component of the soil N pool and plays an essential role in soil ***,the effects of manure substitution on soil labile N in rice cropping systems and their relationships with soil properties,fertilization practices,and climatic conditions remain unclear and should be systematically ***,we investigated rice grain yield and four types of soil labile N that have been widely reported,including available nitrogen(AN),ammonium nitrogen(NH_(4)^(+)-N),nitrate nitrogen(NO_(3)^(−)-N),and microbial biomass nitrogen(MBN).We reviewed 187 published articles and performed a meta-analysis to quantify the effects of manure substitution on yield and soil labile *** results showed that manure substitution increased AN,MBN,NH+4-N,and NO−3-N by 11.3%,38.5%,5.9%,and 8.1%,*** substitution significantly increased the yield by 1.4%–5.9%,but full substitution significantly decreased the yield by 2.9%.The positive effects of manure substitution on yield and AN were stronger with long-term *** differences in responses varied across specific manure types,N application rates,soil properties,and climatic *** conclusion,manure substitution can increase soil labile N and is regarded as an efficient strategy for improving soil N fertility and a recommended measure for applying both chemical and organic fertilizers in rice *** study provides evidence of the effects of manure substitution on yield enhancement by increasing soil labile N.

关键词： available nitrogen climatic factors fertilization practices manure substitution microbial biomass nitrogen soil properties

Hotspots and trends of biological water treatment based on bibliometric review and patents analysis

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Journal of Environmental Sciences 2023年第3期125卷 774-785页

作者： Lili Jin Xiangzhou Sun Hongqiang Ren hui huang State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China

In order to reveal the hotspots and trends of biological water treatment from the perspectives of scientific and technological innovation, both of the bibliometric review and patents analysis were performed in this study. The Web of Science Core Collection database and Derwent Innovation Index database recorded 30023 SCI papers and 50326 patents, respectively were analyzed via information visualization technology. The results showed that China ranked the first in both papers and patents, while the United States and Japan had advantages in papers and patents, respectively. It was concluded through literature metrology analysis that microbial population characteristics, biodegradation mechanism,toxicity analysis, nitrogen and phosphorus removal and biological treatment of micropolluted wastewater were the research hotspots of SCI papers. Activated sludge process and anaerobic-aerobic combined process were the two mainstream technologies on the basis of patent technology classification analysis. Technology evolution path of biological water treatment was also elucidated in three stages based on the citation network analysis. Furthermore, the future directions including research on the law of interaction and regulation of biological phases and pollutants and the technology innovations towards the targeted biotransformation or selective biodegradation of pollutants and resource reuse of wastewater were prospected.

关键词： Biological water treatment Bibliometric review Patent analysis Technology evolution path