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Synthesis,Spectroscopic Properties and Structural Characterization of Sodium Potassium Citrato Oxotungstate(VI)Dimer

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Chinese Journal of Structural Chemistry 2000年第3期19卷 181-186页

作者： WANG Geng zhou zhao-hui ZHANG hui YE Jian-Liang WAN hui-Lin Department of Chemistry and State Key Laboratory for Physical Chemistry of Solid Surface Xiamen UniversityXiamen361005

The sodium potassium citrato oxotungstate(VI) dimer, Na 4K 2〔W 2O 5\|(cit) 2〕·11H 2O (H 4cit = citric acid) was obtained by the reaction of sodium tungstate(VI) and excess potassium citrate monobasic (KH 3cit) in neutral solution. The crystal data for the title compound: monoclinic, C 12 H 30 K 2Na 4W 2O 30 , M r =1192.21, space group P2 1/n, a=17.427(4), b=10.022(2), c=18.637(3) , β=92.62(1)°, V=3252(2)  3, Z=4, D c =2.435 g/cm 3, μ( Mo Kα )=76.38 cm -1 , F( 000)=2288. The structure was refined to R =0.0434 for 6327 independent observed reflections with I>3σ(I) . The complex anion contains a quasi centrosymmetric (O 2W)O b(WO 2) core with a bent bridging oxo group 〔W-O b-W 175.0(4)°〕. Each citrate as tridentate ligand coordinates to a tungsten atom through the alkoxy, α carboxyl, and one β carboxyl group, while the other β carboxyl group remains uncoordinated. Principal dimensions are: W-O b 1.883(6) , (W=O t)av 1.715(6) , W-O (alkoxy) 1.959(6) , W-O ( α carboxy) 2.176(6)  and W-O ( β carboxy) 2.231(6) . The tungsten atom is located in a distorted octahedron environment.

关键词： oxotungstate(VI) citrate citric acid citrate method crystal structure

Effects of Shot Peening Process on Thermal Cycling Lifetime of TBCs Prepared by EB-PVD

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Chinese Journal of Aeronautics 2007年第2期20卷 145-147页

作者： zhou zhao-hui GONG Sheng-kai LI He-fei XU hui-bin ZHANG Chun-gang WANG Lu School of Materials Science and Engineering Beij＇ing University of Aeronautics and Astronautics Beij＇ing 100083 China Shenyang Liming.4ero-Engine Group Corporation Shenyang 110043 China

Conventional two-layered thermal barrier coatings （TBCs） are prepared by electron beam physical vapor deposition （EB-PVD） with ZrO2-8 wt% Y2O3 （8YSZ） as top coat and CoCrAlY as bond coat on disk-shaped Ni based super-alloy. In this paper, three kinds of shot peening process with different lengths of operating time were adopted for bond coating. As a result, changes took place in its surface roughness and the surface micro-hardness. A thermal cycling test at 1 273 Kx55 rain and another at room temperature for 5 min were performed to study the effects of shot peening process on the thermal cycling lifetime of TBCs. It is found that a moderate shot peening process will be able to prolong the life time. The oxidation dynamic of the as-processed TBCs basically accords with the parabolic rule, and the oxidation test also attests to the spallation between YSZ and thermal growth oxide （TGO） responsible mainly for the failure of TBCs.

关键词： thermal cycling lifetime shot peening thermal barrier coatings (TBCs)

Synthesis and Structure of（NH4）₂ [V2O₄（OCH₂COO）₂]

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Chemical Research in Chinese Universities 1994年第2期10卷 102-106页

作者： zhou, zhao-hui Wang, Jin-zhi Wan, hui-lin Tsai, Khi-rui

imeric ammonium(glycollate)dioxovanadium (NH4)2[V2O4(OCH2COO )2]has been prepared. The complex crystallizes in triclinic space group Pl with unitcell parameters: a = 0. 6124(1)nm, b= 0. 6952 (1)nm, c= 0. 8449 (1)nm, α=66. 08 (1),β=64. 21(1),γ= 78. 01(1)°V=0. 2958 nms, Z=1, R=0. 041. Thedimer contains a quasicentrosymmetric planar four-membered V2O2 ring with twoexocyclic glycollate entities coordinated by the oxygen atoms of hydroxy- and car-boxy late ligands .

关键词： Hydroxycarboxylate Vanadium complex Molecular structure

Effective VTeO/SBA-15 Catalyst Prepared by Precursor Method for the Selective Oxidation of Propane to Acrolein

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Chemical Research in Chinese Universities 2008年第6期24卷 793-797页

作者： FENG Mao-ying HUANG Chuan-jing WENG Wei-zheng WAN hui-lin XU Qin zhou zhao-hui College of Chemistry and Chemical Engineering State Key Laboratory for Physical Chemistry of Solid Surface National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 P. R. China

Precursor decomposition was used for the preparation of VTeO/SBA-15 catalyst for the selective oxidation of propane to acrolein. The catalyst shows a better performance compared with those prepared by conventional impregnant method. A yield of 9.3% of acrolein was achieved with 2% V loadings at 500 ℃. XRD, N2-adsorption, H2-TPR, Py-IR and XPS measurements were used to unclose the relationship between the structure and performance of the catalyst.

关键词： Acrolein Propane Vanadium catalyst Precursor decomposition

岩心多孔介质中乳状液乳化性能评价和驱油效果研究

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应用化工 2024年第5期53卷 1003-1008,1014页

作者：马良周朝辉杜猛陆舒艺李根张群韩璐刘先贵中国科学院大学工程科学学院北京100049 中国科学院渗流流体力学研究所河北廊坊065007 中国石油勘探开发研究院北京100083 提高油气采收率全国重点实验室北京100083 北京师范大学生命科学学院北京100875 东北石油大学非常规油气研究院黑龙江大庆163318

综合利用全能红外稳定分析仪、光学显微镜及多功能流变仪,从宏观和微观角度开展了不同复合体系在岩心渗流和机械搅拌下生成乳状液的稳定性、黏度及微观形态变化特征实验研究。在此基础上,辅以岩心驱油实验,研究了不同乳状液复合体系的... 详细信息

综合利用全能红外稳定分析仪、光学显微镜及多功能流变仪,从宏观和微观角度开展了不同复合体系在岩心渗流和机械搅拌下生成乳状液的稳定性、黏度及微观形态变化特征实验研究。在此基础上,辅以岩心驱油实验,研究了不同乳状液复合体系的驱油效果。结果表明,甜菜碱表面活性剂二元体系可在岩心多孔介质驱油过程中有效生成乳状液,机械搅拌状态下不同复合体系稳定性差异显著。二元、无碱A、三元体系的机械搅拌剪切与岩心渗流生成乳状液的TSI值具有反向关联的关系,而在乳状液黏度上二者具有正向关联的关系。相比于岩心剪切,机械搅拌剪切应力较大,不同体系生成的乳状液液滴粒径更小,能够更显著地区分出不同体系之间乳状液相态区别。岩心驱油实验过程中,整体渗流阻力与提高采收率幅度存在反向相关的关系,不同等黏度体系提高采收率幅度依次升高,且具有显著的梯度差异,二元、三元、无碱A体系不仅可以通过乳化封堵起到调剖作用,扩大波及体积,进而提高洗油效率,乳化流体还可以进入水驱难以波及的微孔区域中洗油、刮油,通过乳化携带作用,降低残余油饱和度,改善驱油效果。

关键词：乳状液乳化评价提高采收率化学驱渗流阻力驱油效果

Wood use and forest management by Neolithic millet farmers at the Xinglong site,northern China

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Science China Earth Sciences 2024年第6期67卷 1910-1921页

作者： hui SHEN Zhenwei QIU Keliang zhao Xinying zhou Xiaoqiang LI Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China National Museum of China Beijing 100006China University of Chinese Academy of Sciences Beijing 100049China

The origin and development of agriculture and its relationship with climate change are hotly debated topics among environmental *** this study,we analyzed wood charcoal materials from the Neolithic Xinglong site in northern China in order to understand the woody vegetation around the site and how early millet farmers shaped local *** results suggest that the area around the Xinglong sites during 8700-7000 yr BP was primarily woodlands,including Prunus sibirica shrubs,Ulmus and Acer forests,and Populus stands near *** 8000 to 7000 yr BP,the warm and humid climate probably contributed to the expansion of Acer,Rhamnus,and Juniperus,and may have facilitated the development of early millet *** these ancient wood fragments that we studied,the high percent of Prunus charcoal appears to indicate an abundance of fruit trees,which might have constituted the main component of local ***,the wood taxa illustrate the existence of a variety of ecological habitats,and it is logical to assume that people made full use of the locally available wood ***,Populus and Ulmus were the dominant sources of *** results of tree-ring curvature analyses indicate that people mainly collected trunks or large branches of Ulmus,Populus,Acer,and Juniperus *** interpret the increasing use of Prunus twigs and the declining percentage of Prunus charcoal in the period between 8000-7000 yr BP as indicating that people started to protect and manage wild fruit *** may have started pruning to acquire more food resources as part of the cultural responses and adaptation strategies employed by these early millet cultivators.

关键词： Xinglong site Wood charcoal Wood use Woodland management

A Study of Pt^(4+)Adsorption and Its Reduction by Bacillus Megaterium D01

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Chemical Research in Chinese Universities 2000年第3期16卷 246-249页

作者： LIU Yue ying FU Jin kun zhou zhao hui YU Xin sheng YAO Bing xin Department of Biology Department of Chemistry Xiamen UniversityXiamen 361005P.R.China

The properties of Pt 4+ adsorption and its reduction by Bacillus megaterium D01 were studied by means of ICP, anode stripping voltammetry, TEM, IR and XPS. The results of ICP analyses showed that the Pt 4+ adsorptive efficiency of the strain D01 was as high as 94.3% under the conditions of 100 mg Pt 4+ /L, 1 g biomass/L, pH 3.5 and at 30 ℃ for 24 h. Moreover, it was confirmed from anode stripping voltammetry that the strain D01 possessed a strong reducibility. The TEM analysis indicated that the strain D01 was able to adsorb and reduce Pt 4+ to Pt 0, small particles. The XPS result further supported the reduction of Pt 4+ to Pt 2+ , followed by the further recuction to Pt 0. The IR spectrum implied that D01 biomass adsorption of Pt 4+ may result in the complexation of the CO bond to the Pt species.

关键词： Biosorption Bioreduction Platinum Bacillus megaterium

Failure mechanism and safety control technology of a composite strata roadway in deep and soft rock masses:a case study

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Journal of Mountain Science 2024年第7期21卷 2427-2444页

作者： zhao Chengwei zhou hui SUN Xiaoming ZHANG Yong MIAO Chengyu WANG Jian State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The construction of coal mines often encounters deep composite soft rock roadways,which is characterized by significant deformation and poor *** deeply study the failure mechanism and large deformation challenges of a composite strata roadway in deep and soft rock masses,a numerical model of 3DEC tetrahedral blocks was established based on the method of rock quality designation(RQD).The results showed that original support cannot prevent asymmetric failure and large deformation due to the adverse geological environment and unsuitable support *** to the failure characteristics,a coupling support of“NPR bolt/cable+mesh+shotcrete+steel pipe”was proposed to control the stability of the surrounding *** excellent mechanical properties of large deformation(approximately 400 mm)and high constant resistance force(bolt with 180 k N;cable with 350 k N)were evaluated by the tensile *** numerical results showed that the maximum deformation was minimized to 243 mm,and the bearing capacity of the surrounding rock of the roadway was *** field test results showed that the maximum deformation of the surrounding rock was 210 mm,and the forces of the NPR bolt and cable were stable at approximately 180 k N and 350 k N,*** demonstrated the effectiveness of the coupling support with the NPR bolt and cable,which could be a guiding significance for the safety control of large deformation and failure in deep composite soft rock roadways.

关键词： 3DEC Composite strata roadway Soft rock NPR bolt and cable Asymmetric large deformation

Phase field modeling of grain stability of nanocrystalline alloys by explicitly incorporating mismatch strain

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Rare Metals 2024年第7期43卷 3370-3382页

作者： Min zhou Hong-hui Wu Yuan Wu hui Wang Xiong-Jun Liu Sui-He Jiang Xiao-Bin Zhang zhao-Ping Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutrality University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra ct Nanocrystalline materials exhibit unique properties due to their extremely high grain boundary(GB) ***,this high-density characteristic induces grain coarsening at elevated temperatures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migration,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integrates mismatch strain,solute segregation and precipitation was developed to evaluate the influence of lattice misfit on the thermal stability of nanocrystalline *** simulation results indicated that introducing a suitable mismatch strain can effectively enhance the microstructural stability of nanocrystalline *** synergizing precipitation with an appropriate lattice misfit,the formation of second-phase particles in the bulk grains can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentrated solute segregation and precipitation at the GBs effectively hinders grain migration,thereby preventing grain *** findings provide a new perspective on the design and regulation of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch strain Second-phase precipitation Grain boundary segregation Nanocrystalline alloys