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Co evolutions for WC-Co with different Co contents during pretreatment and HFCVD diamond film growth processes

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Transactions of Nonferrous Metals Society of China 2018年第3期28卷 469-486页

作者： Xin-chang WANG cheng-chuan WANG Wei-kai HE Fang-hong SUN State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Physics and Technology University of Ji’nanJi’nan 250022China

Systematical researches were accomplished on WC-Co with different Co contents(6%,10%and 12%,mass fraction).Based on the XPS and EDX,from orthogonal pretreatment experiments,it is indicated that the acid concentration,the time of the acid pretreatment and the original Co content have significant influences on the Co-removal depth(D).Moreover,the specimen temperature,original Co content and Co-removal depth dependences of the Co evolution in nucleation,heating(in pure H2 atmosphere)and growth experiments were discussed,and mechanisms of Co evolutions were summarized,providing sufficient theoretical bases for the deposition of high-quality diamond films on WC-Co substrates,especially Co-rich WC-Co *** is proven that the Co-rich substrate often presents rapid Co *** high substrate temperature can promote the Co diffusion in the pretreated substrate,while acts as a Co-etching process for the untreated *** is finally found that the appropriate Co-removal depth for the WC-12%Co substrate is 8-9μm.

关键词： HFCVD diamond film WC-Co Murakami-acid pretreatment Co content Co evolution

Fine mapping of susceptibility genes by Lewontin's linkage disequilibrium measure with application to Alzheimer's disease

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Chinese Medical Journal 2002年第8期115卷 113-120页

作者： Gordon Gong Gleb Haynatzki Robert R.Recker John Mordeson Shih chuan cheng Nelson Fong Creighton University Osteoporosis Research Center 601 North 30th Street Suite 6730 Omaha NE 68131 USA. gdgong@creighton.edu

Objectives To formulate an equation for fine mapping of disease loci under complex conditions and determine the marker-disease distance in a specific case using this equation. Methods Lewontin’s linkage disequilibrium (LD) measure D’ was used to formulate an equation for mapping disease genes in the presence of phenocopies, locus heterogeneity, gene-gene and gene-environment interactions, incomplete penetrance, uncertain liability and threshold, incomplete initial LD, natural selection, recurrent mutation, high disease allele frequency and unknown mode of inheritance. This equation was then used to determine the distance between a marker (ε4 within the apolipoprotein E gene, APOE) and Alzheimer’s disease (AD) loci using published *** An equation was formulated for mapping disease genes under the above conditions. If these conditions are present but ignored, then recombination fraction θ between marker and disease loci will be either overestimated or estimated with little bias. Therefore, an upper limit of θ can be obtained. AD has been found to be associated with the marker allele ε4 in Africans, Asians, and Caucasians. This suggests that the AD-ε4 allelic LD predates the divergence of peoples occurring 100?000 years ago. With the age of AD-ε4 allelic LD so estimated, the maximal distance was calculated to be 23.2 kb (mean 5.8 kb). Conclusions (1) A method is developed for LD mapping of susceptibility genes. (2) A mutation within the APOE gene itself, among others, is responsible for the susceptibility to AD, which is supported by recent evidence from studies using transgenic mice.

关键词： linkage disequilibrium mapping complex trait phenocopies penetrance mutation selection susceptibility genes

Trace determination of hexabromocyclododecane diastereomers in water samples with temperature controlled ionic liquid dispersive liquid phase microextraction

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Chinese Chemical Letters 2011年第1期22卷 97-100页

作者： Ru Song Zhao Xia Wang Jin Peng Yuan Shan Shan Wang chuan Ge cheng Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Analysis and Test Center Shandong Academy of Sciences Jinan 250014 China

A novel temperature controlled ionic liquid dispersive liquid phase microextracfion （TCIL-DLPME） coupled with rapid resolution liquid chromatography-electrospray tandem mass spectrometry （RRLC-ESI-MS-MS） has been developed for the enrichment and determination of three hexabromocyclododecane diastereomers （HBCDs） in water samples. Green solvent ionic liquid （IL） was used as extraction solvent instead of toxic organic solvents. This technique also avoided the usage of dispersive solvent. Some important parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. All the limits of detection for the three diastereomers were 0.1 ng/ mL. The linear range was obtained in the range of 1-100 ng/mL for the total amount of three HBCD diastereomers. It was satisfactory to analyze real environmental water samples with the recoveries ranging from 77.2% to 99.3%. The main advantage of the method is toxic organic solvent-free.

关键词： Hexabromocyclododecane Temperature controlled ionic liquid dispersive liquid phase microextraction Rapid resolution liquidchromatography-electrospray tandem mass spectrometry

Polyurethane networks based on disulfide bonds:from tunable multi-shape memory effects to simultaneous self-healing

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Science China Materials 2019年第3期62卷 437-447页

作者： Xiao-Ying Deng Hui Xie Lan Du cheng-Jie Fan chuan-Ying cheng Ke-Ke Yang Yu-Zhong Wang Center for Degradable and Flame-Retardant Polymeric Materials(ERCEPM-MoE) College of ChemistryNational Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China

With the prompt development in intellectualization nowadays, the smart materials with multifunctionality or multi-responsiveness are highly expected. But it is a big challenge to integrate the different actuating units into a single system in a synergy pattern. Herein, we put forward a new strategy to develop the polyurethane networks which can present shape-memory effect and self-healing effect in independent way as well as simultaneous acting mode. To realize this goal, poly(tetremethylene ether) glycol was chosen as the soft segment to ensure the polymer chains a good mobility, and disulfide bond as the dynamic covalent bond was embedded in the backbone of polyurethane to endow it with desirable self-healing capacity under mild condition. Moreover, a rational control of the architecture of the networks by adjusting the content of disulfide bond and the degree of cross-linking, a broad glass transition temperature(T_g) was achieved, which enabled the network a versatile shape-memory effect, covering from dual-, triple-so far as to quadrupleshape memory effect. More importantly, the shape recovery and healing process can be realized simultaneously because of the highly matched actuating condition in this system.

关键词： polyurethane network disulfide bond self-healing shape-memory

Topological Charge Conversion with Spiral-Slit Screens

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Chinese Physics Letters 2013年第10期30卷 108-111页

作者： LI Zhen-Hua ZHANG Mei-Na LI Xing LIU Chun-Xiang cheng chuan-Fu College of Physics and Electronics Shandong Normal UniversityJinan 250014

We propose a method of converting the topological charge(TC)of an incident vortex light wave with spiral-slit *** phase in the incident vortex beam is redistributed via the optical path adjustment realized by changing the in-plane radial distance of the spiral *** numerically calculate the light field with Fresnel diffraction theory,and find the expected TC conversion on the observation *** calculations also show that screens of pinholes distributed in a spiral curve can be used for the implementation instead of spiral *** method can also be used to distinguish the TCs of the incident vortices by reading the diffracted intensity patterns.

关键词： incident vortex topological

Genomic characteristics of Dickeya fangzhongdai isolates from pear and the function of type Ⅳ pili in the chromosome

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Journal of Integrative Agriculture 2020年第4期19卷 906-920页

作者： CHEN Bin TIAN Yan-li ZHAO Yu-qiang WANG Yuan-jie chuan Jia-cheng LI Xiang HU Bai-shi College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests Ministry of EducationNanjing Agricultural UniversityNanjing 210095P.R.China Institute of Botany Jiangsu Province and Chinese Academy of Sciences(Nanjing Botanical Garden Mem.Sun Yat-Sen)/Jiangsu Key Laboratory for the Research and Utilization of Plant ResourcesNanjing 210014P.R.China Charlottetown Laboratory Canadian Food Inspection AgencyCharlottetownPE C1A5T1Canada

Dickeya fangzhongdai, the causal agent of bleeding canker of pear, is a new member of the Dickeya genus and the only one that infects woody plants. Recent studies have reclassified several Dickeya isolates as D. fangzhongdai, which were isolated from various environments, including water, Phalaenopsis sp. and Aglaonema sp. To provide genomic characterization of D. fangzhongdai isolates from pear, the genomes of D. fangzhongdai strain JS5(=China General Microbiological Culture Collection Center, CGMCC 1.15464 ~T=DSM 101947 ~T), along with two other isolates, LN1 and QZH3, were sequenced and compared to those of other Dickeya spp. Homology greater than 99% was observed among three D. fangzhongdai strains. Plasmid, type IV secretion system(T4 SS) and type IV pili(TFPs) were found in genomes of D. fangzhongdai isolates. Comparative analysis of the type Ⅲ secretion systems(T3 SS), type Ⅲ secretion effectors(T3 SE), plant cell wall degradation enzymes(PCWDE) and membrane transport proteins of Dickeya spp. showed some differences which might reflect the variations of virulence, phylogenetic and phenotypic characteristics of Dickeya spp. In addition, deletion mutant of TFP in D. fangzhongdai JS5 showed no twitching motility and reduced virulence and biofilm formation. The fingdings of the distinctive plasmid, T4 SS and TFPs, as well as the differences of T3 SE, PCWDE and membrane transport proteins make D. fangzhongdai isolates unique. These results also suggested that acquisition of virulence genes by horizontal gene transfer might play some role in the genetic variation of D. fangzhongdai.

关键词： Dickeya fangzhongdai comparative genomics virulence typeⅣpili

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不同含水率断层宏微观破裂与强度折减损伤

科学技术与工程 2024年第9期24卷 3773-3780页

作者：高涛陈云娟敬艺刘建民王津津杨传成宋润钊山东省地震局济南250014 山东省地震工程研究院济南250021 山东建筑大学土木工程学院济南250101 山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室济南250101 山东大学齐鲁交通学院济南250002

为探究深部地区断层花岗岩不同含水率的宏观与微观跨尺度性质,开展了轴压力学试验、扫描电镜(scanning electron microscope,SEM)试验和X射线衍射(X-ray diffraction,XRD)试验,分析其多尺度破裂与强度折减损伤关系。结果表明:无水状态... 详细信息

为探究深部地区断层花岗岩不同含水率的宏观与微观跨尺度性质,开展了轴压力学试验、扫描电镜(scanning electron microscope,SEM)试验和X射线衍射(X-ray diffraction,XRD)试验,分析其多尺度破裂与强度折减损伤关系。结果表明:无水状态下宏观以剪切破坏为主且破裂面平滑,而随着含水率提高,其破裂模式以张拉破坏为主,裂纹路径与主应力方向平行且整体松散;低含水率工况微观破裂为沿晶破裂,高含水率工况为沿晶破裂和穿晶破裂的复合型破坏;吸水中期峰值强度与弹性模量两指标衰减率为前期6倍,达到衰减幅度最大限并呈非线性指数下降,吸水后期两指标衰减率回弹至前期状态;劣化系数随含水率增长而降低,吸水前期水分子起润滑岩石内部矿物作用,中后期阶段水分子发生侵蚀软化导致强度大幅度折减。

关键词：深部断层花岗岩破裂模式微观机制强度折减

Influence of alloy ingredients on mechanical properties of ternary boride hard alloy clad materials

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中国有色金属学会会刊：英文版 2004年第z1期14卷 482-486页

作者： LIU Fu-tian SONG Shi-xue YANG Jun-ru HUANG Wei-ling HUANG chuan-zhen cheng Xin LI Zhao-qian School of Materials Science and Engineering Ji''nan University Ji''nan 250022 China School of Mechanical Engineering Shandong University Ji''nan 250061 China Techinal Center Ji''nan Iron & Steel Group Corporation Ji''nan 250101 China School of Materials Science and Engineering Ji''nan University Ji''nan 250022 China School of Mechanical Engineering Shandong University Ji''nan 250061 China School of Mechanical Engineering Shandong University Ji''nan 250061 China School of Mechanical Engineering Shandong University Ji''nan 250061 China School of Materials Science and Engineering Ji''nan University Ji''nan 250022 China School of Mechanical Engineering Shandong University Ji''nan 250061 China

Using Mo, B-Fe alloy and Fe powders as raw materials, and adding C, Cr and Ni ingredients, respectively, or C, Cr and Ni mixed powders, ternary boride hard alloy clad materials was prepared on Q235 steel substrate by means of in-situ reaction and vacuum liquid phase sintering technology. The influence of alloy ingredients on the mechanical properties of ternary boride hard alloy clad materials was investigated. The results indicate that a mixture of 0.8% C, 5% Cr and 2% Ni ingredients gives a ternary boride hard alloy clad material with optimal mechanical properties, such as high transverse rupture strength, high hardness and good wear resistance.

关键词： hard alloy cladding liquid phase sintering alloying ingredient transverse rupture strength hardness wear resistance

Computational Generation and the Simulation of the Light Scattering of Self-Affine Fractal Random Surface

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Chinese Physics Letters 2001年第2期18卷 217-219页

作者： LIU Wen-Xian TENG Shu-Yun ZHANG Ning-Yu LIU De-Li cheng chuan-Fu Department of Physics Shandong Normal UniversityJi’nan 250014

We propose a method for the generation of self-affine fractal random surfaces,in which we use Fourier transform and its inversion in the *** light scattering of surfaces of this kind is simulated at different incident angles of *** variation of the full width at half maximum(FWHM)of the intensity profile versus the perpendicular component k_(⊥)of the wave-vector shows clearly the characteristics of the surfaces *** simulation demonstrates how the value of FWHM at k^(2)_(⊥)w^(2)≤1 region and the slope of ln wp-ln k_(⊥)curve at k^(2)_(⊥)w^(2)≥1 region are used,respectively,to extract the lateral correlation lengthξand the roughness exponentα.

关键词： scattering Fractal illumination