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AFM STUDY ON THE MORPHOlOGICAl CHANGE OF Zn ElECTRODEPOSIT

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Acta Metallurgica Sinica(English letters) 2003年第5期16卷 360-364页

作者： A.l.Fan W.H.Tian M.Kurosaki DepartmentofMaterialsPhysicsandChemistry UniversityofScienceandTechnologyBeijingBeijing100083China SteelResearchlaboratories NipponSteelCorporation20-1ShintomiFuttsuChiba-Ken293-8511Japan

Nano-sized growth of zinc electrodeposit on the ferrite substrate has been studied by means of in situ scanning tunnel microscopy (STM) and atomic force micoscopy (AFM). It is found that the morphology of zinc electrodeposit varies from initial about 30nm granular crystals to layered platelet crystals with increasing deposition time by using in situ STM. With AFM, the results show that the platelet crystals are hexagonal in shape and the hexagonal platelet crystals form steps perpendicular to the growth direction by side-by-side stacking along the (0001)η surface. The mechanism of morphological change is discussed in details. It is proposed that these steps grow laterally as a result of the embedment of zinc ion clusters.

关键词： zinc electrodeposit atomic force microscopy crystal morphology step growth scanning tunnel microscopy

Synthesis and crystal Structure of (CO) 5ReSnMe 2Re(CO) 5

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Chinese Journal of Structural Chemistry 1999年第2期18卷 39-43页

作者： li, J liu, H Song, XQ Kai, l Yin, N Nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China

The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (NO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl.ligands and one Sn atom, forming an octahedral structure.

关键词： metal carbonyl cluster Re complex synthesis crystal structure

Ordering-induced Elinvar effect over a wide temperature range in a spinodal decomposition titanium alloy

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Journal of Materials Science & Technology 2023年第19期150卷 245-255页

作者： D.l.Gong H.l.Wang S.H.Hao P.liu X.Yang Y.N.Jiang W.J.Wang K.lin B.li K.Du Y.D.Wang R.Yang Y.l.Hao Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Shenyang National.laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Analysis and Testing Center Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryDepartment of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China State Key laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

Temperature-independent elastic modulus is termed as Elinvar effect,which is available by tuning the continuous spin transition of ferromagnetic alloys via composition optimization and the first-order martensitic transformation of shape memory alloys via plastic ***,these reversible mechanisms are restricted generally in a narrow temperature range of less than 300 *** reports,by tuning a spinodal decomposition in a Ti-Nb-based titanium alloy via aging treatment,both the Elinvar effect in a wide temperature range of about 500 K and a high strength-to-modulus ratio of about 1.5%can be obtained by a continuous and reversible crystal ordering *** results demonstrate that the alloy aged at 723 K for 4 h has a nanoscale plate-like modulatedβ+α"two-phase microstructure and its elastic modulus keeps almost constant from 100 to 600 *** and in-situ X-ray diffraction measurements reveal that the crystal ordering parameter of theα"phase increases linearly with temper-ature from 0.88 at 133 K to 0.97 at 523 K but its volume fraction keeps a constant of about 33.8%.This suggests that the continuous ordering of theα"phase toward the high modulusαphase induces a posi-tive modulus-temperature relation to balance the negative relation of the elastically stableβ*** aged alloy exhibits a high yield strength of 1200 MPa,good ductility of 16%and a high elastic admissible strain of 1.5%.Our results provide a novel strategy to extend the Elinvar temperature range and enhance the strength by tuning the crystal ordering of decomposition alloys.

关键词： Titanium alloy Spinodal decomposition crystal ordering Elinvar effect Mechanical properties

高压辊磨强化粗粒铁矿粉制备高品质球团的规律

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中国冶金 2024年第5期34卷 89-97页

作者：吕浩甘敏文小平赵改革谢路奔范晓慧张凯中南大学资源加工与生物工程学院湖南长沙410083 湖南华菱湘潭钢铁有限公司湖南湘潭411101 湘潭瑞通球团有限公司湖南湘潭411101 成都利君实业股份有限公司四川成都610045

利用粗粒铁矿粉替代部分铁精矿生产氧化球团可降低原料成本,然而粗粒铁矿粉中粗颗粒含量高、成球与焙烧性能不佳,导致其制备的球团强度低,因此难以大量配加。研究了高压辊磨预处理对粗粒铁矿粉制备氧化球团的影响。结果表明,高压辊磨后... 详细信息

利用粗粒铁矿粉替代部分铁精矿生产氧化球团可降低原料成本,然而粗粒铁矿粉中粗颗粒含量高、成球与焙烧性能不佳,导致其制备的球团强度低,因此难以大量配加。研究了高压辊磨预处理对粗粒铁矿粉制备氧化球团的影响。结果表明,高压辊磨后粒度大于1 mm粒级的粗粒铁矿粉含量显著降低,微细粒含量增加,比表面积增大;相较于提高辊磨压力,增加辊磨次数更有利于粗颗粒的破碎,此外粗粒铁矿粉的适宜给料水分较低。高压辊磨可以改善颗粒表面性质,增强粗粒铁矿粉的亲水性与成球性,有利于生球质量的提高;同时,在机械力作用下含铁矿物发生晶体活化,当辊磨压力提高至12 MPa以上时机械活化作用更强,这有利于颗粒间固相反应的进行,从而提高球团强度。采用粒度小于1 mm粒级的粗粒铁矿粉进行球团试验,与未处理的粗粒铁矿粉相比,经辊磨压力14 MPa、给料水分(质量分数)3.5%、两次开路辊磨处理后,在相同的球团制备工艺下,粗粒铁矿粉配比(质量分数)可由15%提高至30%;当保持粗粒铁矿粉配比为15%时,焙烧球强度可提高589 N/个。研究结果为拓宽球团原料种类、降低预处理能耗与球团成本提供了理论和技术指导。

关键词：粗粒铁矿粉高压辊磨机械活化氧化球团抗压强度

藤椒精油抗芽孢杆菌生物被膜关键组分的分子对接虚拟筛选与活性评价

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食品科学 2024年第12期45卷 125-135页

作者：肖瑀晗吕昕昱张莹凡原鹏飞周曼侯晓艳陈安均张志清申光辉四川农业大学食品学院四川雅安625014

为探讨藤椒精油抗腐败解淀粉芽孢杆菌生物被膜的关键活性组分及其胞内作用靶点,根据文献报道构建藤椒精油组分数据库和芽孢杆菌生物被膜形成相关靶蛋白分子结构集,采用CB-DOCK2进行藤椒精油组分与生物被膜形成相关靶蛋白的分子对接,根... 详细信息

为探讨藤椒精油抗腐败解淀粉芽孢杆菌生物被膜的关键活性组分及其胞内作用靶点,根据文献报道构建藤椒精油组分数据库和芽孢杆菌生物被膜形成相关靶蛋白分子结构集,采用CB-DOCK2进行藤椒精油组分与生物被膜形成相关靶蛋白的分子对接,根据分子亲和能力筛选精油抗细菌生物被膜的关键组分及潜在作用靶点。最后通过离体培养结合结晶紫染色法进行藤椒精油关键活性组分石竹烯和氧化石竹烯的抗生物被膜实验验证。分子对接结果表明,藤椒精油的24种挥发性成分与58个解淀粉芽孢杆菌生物被膜形成相关的靶点具有不同的亲和能力,其中氧化石竹烯和β-石竹烯可通过超共轭效应和疏水相互作用、范德华力等分子间作用力与ComP、RapC紧密结合并形成稳定构象。离体生物被膜培养验证实验表明,氧化石竹烯和β-石竹烯对解淀粉芽孢杆菌的最小生物被膜抑制质量浓度分别为6.0 mg/ml和2.0 mg/ml。此外,氧化石竹烯和β-石竹烯还能干扰菌体泳动能力,降低细胞初始黏附和自聚集能力,改变细胞表面疏水性。研究结果揭示了藤椒精油抗细菌生物被膜的关键活性组分及其潜在作用靶点,并为解析植物精油生物活性相关胞内分子机理提供了可行的辅助策略。

关键词：分子对接生物被膜藤椒精油芽孢杆菌氧化石竹烯 β-石竹烯

Reaction behaviors of Pb and Zn sulfates during reduction roasting of Zn leaching residue and flotation of artificial sulfide minerals

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 358-366页

作者： Yong-xing Zheng Jilai Ning Wei liu Pan-jin Hu Jin-fang lü Jie Pang State Key laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Faculty of land Resource Engineering Kunming University of Science and TechnologyKunming 650093China School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

To evaluate the feasibility of recovering Pb and Zn sulfides and Ag-containing minerals from Zn leaching residue by the process of reduction roasting followed by flotation,the reaction behaviors of Pb and Zn sulfates during this process were *** analysis showed that the transformation ratios of PbSO4 and ZnSO4 could reach 65.51%and 52.12%,respectively,after reduction roasting,and the introduction of a sulfidation agent could improve the transformation ratios of these *** electron microscopy-energy dispersive spectroscopy(SEM-EDS)revealed that temperature obviously affects the particle size,crystal growth,and morphology of the artificial Pb and Zn sulfide *** size analysis demonstrated that the particle size of the materials increases after *** tests revealed that a flotation concentrate composed of 12.01wt%Pb,27.78wt%Zn,and 6.975×10^(−2)wt%Ag with recoveries of 60.54%,29.24%,and 57.64%,respectively,could be obtained after roasting.

关键词： zinc leaching residue reduction roasting flotation Pb and Zn sulfates artificial sulfides

Hierarchical sodium-rich Prussian blue hollow nanospheres as high-performance cathode for sodium-ion batteries

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Nano Research 2018年第8期11卷 3979-3990页

作者： Xiao Tang Hao liu Dawei Su Peter H. l. Notten Guoxiu wang Center for Clean Energy Technology Faculty of Science University of Technology Sydney Sydney NSW 2007 Australia Department of Chemical Engineering and Chemistry Eindhoven University of Technology Eindhoven 5600 MB The Netherlands Fundamental Electrochemistry (IEKg) Forschungszentrum Julich Julich D-52425 Germany

Recently, Prussian blue and its analogues （PBAs） have attracted tremendous attention as cathode materials for sodium-ion batteries because of their good cycling performance, low cost, and environmental friendliness. However, they still suffer from kinetic problems associated with the solid-state diffusion of sodium ions during charge and discharge processes, which leads to low specific capacity and poor rate performances. In this work, novel sodium iron hexacyanoferrate nanospheres with a hierarchical hollow architecture have been fabricated as cathode material for sodium-ion batteries by a facile template method. Due to the unique hollow sphere morpholog~ sodium iron hexacyanoferrate nanospheres can provide large numbers of active sites and high diffusion dynamics for sodium ions, thus delivering a high specific capacity （142 mAh/g）, a superior rate capabili, and an excellent cycling stability. Furthermore, the sodium insertion/extraction mechanism has been studied by in situ X-ray diffraction, which provides further insight into the crystal structure change of the sodium iron hexacyanoferrate nanosphere cathode material during charge and discharge processes.

关键词： sodium-rich sodium ironhexacyanoferrate hollow nanospheres cathode sodium-ion batteries

Silicon saturation coefficient changes in hydrogarnets during the Bayer process with lime addition

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1965-1972页

作者： Guozhi lü Ting’an Zhang Xiaofeng Zhu Chaozhen Zheng Yanxiu Wang Weiguang Zhang Zimu Zhang Key laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education School of Metallurgy Northeastern University

The relationship between the silicon saturation coefficient of hydrogarnets and Bayer reaction parameters was studied. The peak position, crystal plane spacing, and cell edge length of typical hydrogarnet patterns were calculated to find the key factors influencing the relationship. The results showed that the crystal face(420) is the optimal garnet growth direction during hydration and crystal growth along the faces(521) and(611) were not affected significantly by the varying experimental conditions. The reaction temperature significantly influenced the silicon saturation coefficient of hydrogarnets. The silicon saturation coefficient of hydrogarnets increased from 0.2 to about 1.0 in the temperature range of 30–270 °C and a rapid expansion process was observed in the temperature range of 120–150 °C. Moreover, the reaction time, alumina concentration, and C/S were shown to be less important factors. Averaging the results obtained by the 3 methods was shown suitable for calculating the SiO2 saturation coefficient of hydrogarnets. The calculated results of the Al2O3 and SiO2 contents matched the actual ones. However, the actual SiO2 content was about10 % less than the calculated one for SiO2 saturation coefficients higher than 1.

关键词： Hydrogarnet Saturation coefficient Peak position crystal plane spacing Cell edge length

Structural basis of heparan sulfate-specific degradation by heparinase Ⅲ

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Protein & Cell 2012年第12期3卷 950-961页

作者： Wei Dong Weiqin lu Wallace l.McKeehan Yongde luo Sheng Ye life Sciences Institute Zhejiang UniversityHangzhou 310058China Center for Cancer and Stem Cell Biology Institute of Biosciences and TechnologyTexas A&M Health Science CenterHoustonTexas 77030USA Department of Molecular Pathology The University of Texas MD Anderson Cancer CenterHoustonTexas 77030USA

Heparinase Ⅲ(HepⅢ)is a 73-kDa polysaccharide lyase(Pl)that degrades the heparan sulfate(HS)polysaccharides at sulfate-rare regions,which are important co-factors for a vast array of functional distinct proteins including the well-characterized antithrombin and the FGF/FGFR signal transduction *** functions in cleaving metazoan heparan sulfate(HS)and providing carbon,nitrogen and sulfate sources for host *** has long been used to deduce the structure of HS and heparin motifs;however,the structure of its own is *** we report the crystal structure of the HepⅢ from Bacteroides thetaiotaomicron at a resolution of 1.6Å.The overall architecture of HepⅢ belongs to the(α/α)5 toroid subclass with an N-terminal toroid-like domain and a C-terminal β-sandwich *** of this high-resolution structure allows us to identify a potential HS substrate binding site in a tunnel between the two domains.A tetrasaccharide substrate bound model suggests an elimination mechanism in the HS ***260 and His464 neutralize the carboxylic group,whereas Tyr314 serves both as a general base in C-5 proton abstraction,and a general acid in a proton donation to reconstitute the terminal hydroxyl group,*** structure of HepⅢ and the proposed reaction model provide a molecular basis for its potential practical utilization and the mechanism of its eliminative degradation for HS polysaccarides.

关键词： heparinaseⅢ crystal structure heparan sulfate fibroblast growth factor(FGF) β-elimination