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Recent studies on chemistry of novel μ-CO-containing butterfly Fe/E (E=S,Se,Te) cluster salts

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Science China Chemistry 2009年第1期52卷 1-14页

作者： SOnG LiCheng department of Chemistry, State Key laboratory of Elemento-Organic Chemistry, nankai University, Tianjin 300071, China department of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin China

This article describes recent developments in chemical study on a series of butterfly-shaped μ-CO-containing Fe/E (E = S, Se, Te) cluster salts. These salts include eleven novel cluster anions, which are the single butterfly one μ-CO-containing [(μ-RE)(μ-CO)Fe2(CO)6]- (A), the double butterfly two μ-CO-containing {[(μ-CO)Fe2(CO)6]2(μ-EZE-μ)}2- (B, E = S; C, E = Se), the triple butterfly three μ-CO- containing {[(μ-CO)Fe2(CO)6]3[(μ-SCH2CH2)3n]}3- (D), {[(μ-CO)Fe2(CO)6]3[1,3,5-(μ-SCH2)3C6H3]}3- (E), {[(μ- CO)Fe2(CO)6]3[(μ-SCH2)3CMe]}3- (F), the double butterfly one μ-CO-containing {[(μ-CO)Fe2(CO)6] [Fe2(CO)6][(μ-SCH2)3CMe]} - (G) derived in situ from F, the quadruple butterfly four μ-CO-containing {[(μ- CO)Fe2(CO)6]4[1,2,4,5-(μ-SCH2)4C6H2]}4- (H), the triple butterfly two μ-CO-containing {[(μ-CO)Fe2(CO)6]2 [Fe2(CO)6][1,2,4,5-(μ-SCH2)4C6H2]}2- (I) derived in situ from H, the quadruple butterfly four μ-CO-con- taining {[(μ-CO)Fe2(CO)6]4[(μ-SCH2)4C]}4- (J), and the triple butterfly two μ-CO-containing {[(μ-CO)Fe2 (CO)6]2[Fe2(CO)6][(μ-SCH2)4C]}2- (K) derived in situ from J. This article describes not only the synthetic methods for formation of such anionic cluster (A-K) salts, but also their novel reactions leading to various new types of butterfly Fe/E cluster complexes. All these findings described in this article are important both theoretically and practically.

关键词： butterfly cluster synthesis structure reaction mechanism

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al neutron Absorbing materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.M.Shi n.Li Y.Liu Z.G.Zhang Y.n.Zan Q.Z.Wang B.L.Xiao Z.Y.Ma Shi‑Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key laboratory of nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China department of materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

A statistical model for porous structure of rocks

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Science China(Technological Sciences) 2008年第11期51卷 2040-2058页

作者： JU Yang1,2, YAnG YongMing1, SOnG ZhenDuo3 & XU WenJing4 1 State Key laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing 100083, China 2 department of Mechanical and Manufacturing Engineering, The University of Calgary, 2500 University Drive nW Calgary, AB T2n 1n4, Canada 3 China national Coal Mining Equipment Co. Ltd, Beijing 100011, China 4 department of materials and Metallurgy, The University of Utah, Salt Lake City, Utah 84112, USA State Key laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China department of Mechanical and Manufacturing Engineering The University of Calgary Calgary Canada China national Coal Mining Equipment Co. Ltd Beijing China department of materials and Metallurgy The University of Utah Utah USA

The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

关键词： porous structure statistical model random numbers reconstruction rocks

Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 16-25页

作者： LU Lin1,2,TEnG Bin3,CHEnG Liang 4,SUn Liang5 & CHEn XiaoBo6 1 Center for Deepwater Engineering,Dalian University of Technology,Dalian 116024,China 2 State Key laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116024,China 3 State Key laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China 4 School of Civil and Resource Engineering,The University of Western Australia,Crawly 6003,Australia 5 Centre for Offshore research and Engineering,department of Civil Engineering,national University of Singapore,117576,Singapore 6 research department,Bureau Veritas,neuilly-Sur-Seine,92570,France Center for Deepwater Engineering Dalian University of Technology Dalian China State Key laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China State Key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian China School of Civil and Resource Engineering The University of Western Australia Crawly Australia Centre for Offshore research and Engineering Department of Civil Engineering National University of Singapore Singapore Singapore research department Bureau Veritas Neuilly-Sur-Seine France

Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water *** numerical results are compared with experimental data available in the *** comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably *** the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant *** order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,*** was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial *** was found that μ∈ [0.4,0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2π/L is the wave number and h is the water depth.

关键词： narrow gap fluid resonance water wave viscous fluid model potential flow model finite element method boundary element method

Early J_2 basalts in SE China:Incipience of large-scale late Mesozoic magmatism

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Science China Earth Sciences 2006年第8期49卷 796-815页

作者： XIE Xin1, XU Xisheng1, ZOU Haibo2, JIAnG Shaoyong1, ZHAnG Ming3 & QIU Jiansheng1 1. State Key laboratory of Mineral Deposit research, department of Earth Sciences, nanjing University, nanjing 210093, China 2. department of Earth and Space Sciences, University of California at Los Angeles, Los Angeles, CA90095-1567, USA. 3. GEMOC ARC national Key Centre, department of Earth and Planetary Sciences, Macquarie University, Sydney, n.S.W. 2109, Australia State Key laboratory of Mineral Deposit research Department of Earth Sciences Nanjing University Nanjing China department of Earth and Space Sciences University of California at Los Angeles Los Angeles USA GEMOC ARC national Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney Australia

Magmatism in SE China was dormant during 204―180 Ma, but was reactivated in 180― 170 Ma (early J2), and then became more and more intensive towards the end of early Cretaceous. The small-scale early J2 magmatism is the incipience to long-term and large-scale magmatism in this region. A near east-west (EW) trend volcanic belt was distributed across south Hunan, south Jiangxi and southwest Fujian was formed during early J2 time. Along this belt from the inland toward the coast, the lithology of basalts changes from alkali into tholeiite, and the amount of erupted volcanic rocks and the proportions of rhyolites coexisting with the basalts increase. On the basis of geochemical char- acteristics of these basalts, we infer that the melting degree of source rocks and the extent of frac- tional crystallization and crustal contamination all increased whereas the depth of mantle source de- creased from the inland to the coast, which led to the variations of geological characteristics of the volcanic belt. In early J2, the western spreading Pacific plate began to subduct underneath SE China continental block, reactivating near EW trend deep fault that was originally formed during the Indos- inian event. The stress of the western spreading Pacific plate and the extent of asthenosphere up- welling increased from the inland to the coast, which is consistent with the generation and evolution of early J2 basalts.

关键词： early J2 basalts, upwelling of asthenosphere, large-scale magmatism, SE China, the Pacific plate.

Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in natural Science:materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3, Xu Guanjun1,4, Zhu Cuishan2,3, Xiao Tingrong4, Zhang Min2,3 and Zhang Bin1,4(1. Key laboratory of Petroleum Geochemistry, China national Petroleum Corporation, Beijing 100083, China 2. Geochemistry department of Yangtze University, Jingzhou 434023, China 3. Key laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Jingzhou 434023, China 4. Petroleum Geology Central laboratory, research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China) Key laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry department Yangtze University Jingzhou 434023 China Key laboratory of Exploration Technologies for Oil and Gas Resources Yangtze University Jingzhou 434023 China Petroleum Geology Central laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890n GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a POnA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CnPC Key laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

Thermal decomposition of Pr[（C5H8nS2）3(C12H8n2)]

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Science China Chemistry 2005年第S1期48卷 83-87页

作者： GUO Pengjiang,JIAO Baojuan,CHEn Sanping,HU Rongzu,GAO Shengli & SHI Qizhen department of Chemistry,northwest University Shaanxi Key laboratory of Physico-lnorganic Chemistry,Xi'an 710069,China department of Mathematics,northwest University,Xi'an 710069,China Xi'an Modern Chemistry research Institute,Xi'an 710065,China Shaanxi Key laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi'an 710069 China department of Mathematics Northwest University Xi'an 710069 China Xi'an Modern Chemistry research Institute Xi'an 710065 China

The thermal behavior of the complex Pr[(C5H8nS2)3(C12H8n2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8nS2)3-(C12H8n2)] was decomposed into Pr2S3 and deposited carbon in one step where Pr2S3 predominated in the final products. The results of non-isothermal kinetic calculations showed that the decomposition stage was the random nucleation and subsequent growth mechanism (n = 2/3), the corresponding apparent activation energy ?was 115.89 kJ·mol-1 and the pre-expo-nential constant ln[A/s] was 7.8697. The empirical kinetics model equation was proposed as/(α) =3/2(1-α)[-ln(1-α)]1/*** X-ray powder diffraction patterns of the thermal decomposition products at 800℃under n2 atmosphere show that the product can be indexed to the cubic Pr2S3 phase. The transmission electron microscopy (TEM) of the final product reveals the particle appearance of a diameter within 40 nm. The experimental results show that the praseodymium sulfide nanocrystal can be prepared from thermal decomposition of Pr[(C5H8nS2)3(C12H8n2)].

关键词： Pr[(C5H8nS2)3(C12H8n2)] thermal analysis kinetics noncrystal characteristics

CORROSIOn MOnITORInG OF LY12 In SODIUM CHLORIDE SOLUTIOn WITH ELECTROCHEMICAL nOISE TECHnIQUE

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 91-96页

作者： J.Q. Zhang, Z. Zhang, J.M. Wang, H.B. Shao and C.n. Cao (department of Chemistry, Zhejiang University , Hangzhou 310027, China) (State Key laboratory for Corrosion and Protection of Metals, Institute of Metal research, The Chinese Academy of Sciences, She Dept. of Chem. Zhejiang Univ. Hangzhou 310027 China

Spontaneous electrochemical noise (En) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different techniques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.

关键词： electrochemical noise fractal stochastic analysis dimensionanalysis localized corrosion

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science China Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAn Yi1, ZHEnG ChaoYang2 & WU BaoXiang1 1 Key laboratory of Petroleum Resources research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, China 2 department of Geology, northwest University, Xi’an 710069, China Key laboratory of Petroleum Resources research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China department of Geology Northwest University Xi’an China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in China. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship