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| 1 | Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools(II): Tool positioning strategy显示文摘Based on the mathematical model describing the third-order approximation of the cutter envelope surface according to one given cutter location(CL),a tool positioning strategy is proposed for efficiently machining free-form surfaces with non-ball-end cutters.The optimal CL is obtained by adjusting the inclination and tilt angles of the cutter until its envelope surface and the design surface have the third-order contact at the cutter contact(CC)point,which results in a wide machining strip.The strategy can handle the constraints of machine joint angle limits,global collision avoidance and tool path smoothness in a nature way,and can be applied to general rotary cutters and complex surfaces.Numerical examples demonstrate that the third-order point contact approach can improve the machining strip width greatly as compared with the recently reported second-order one. | ZHU LiMin 1 ,DING Han 2 &XIONG YouLun 2 1State Key Laboratory of Mechanical System and Vibration,Shanghai Jiao Tong University,Shanghai 200240,China 2State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074, China | 2010 | Science China(Technological Sciences)2010，53，8： | 23 |
| 2 | Full-scale measurements of dynamic response of suspension bridge subjected to environmental loads using GPS technology显示文摘Nowadays, there are many larger and taller engineering structures than in the past. These structures are commonly designed to be more flexible. Thus, they are sensitive to severe wind gust and earthquake tremor. For the dynamic response prediction, finite element (FE) modal updating and structural health monitoring, the dynamic characteristics of a structure are becoming increasingly important. The aim of this paper is to show an emerging tool-the real time kinematic (RTK) global positioning system (GPS), which is used to measure and monitor the low-frequency vibration of Dalian BeiDa Bridge, a medium span suspension bridge. The modal analysis is firstly performed on the developed three-dimensional FE model according to the original blue prints of the bridge to provide the analytical frequencies and mode shapes. The field ambient vibration tests using the accelerometers on the bridge deck are conducted just prior to the use of the GPS system in order to validate the FE model. And then, the calibration test is done to assess the dynamic displacement measurement accuracy of the GPS in three orthogonal directions. The GPS signal properties, such as the amplitude, standard deviations (STD), power spectral density (PSD), and probability density functions (PDF), are studied in details. After that, a structural health monitoring system based on the GPS is devised and installed on the bridge to provide real-time measurement of deck movement. The output-only modal parameter identification is carried out by using the Periodogram method to investigate the responses of the bridge. The result shows that the spectral densities of the displacements measured by the GPS correspond well with the results by the FEM analysis and the accelerometer vibration test. It is concluded that the GPS method is reliable and useful to clarify the ambient vibration response behaviors of the flexible structures. The integration of the GPS and accelerometer methods results in a hybrid arrangement that can help to eliminate some disadvantages of the two devices used separately. | YI TingHua1,2, LI HongNan1 & GU Ming2 1State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China 2State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China | 2010 | Science China(Technological Sciences)2010，53，2： | 18 |
| 3 | Aerosol optical depth retrieval by HJ-1/CCD supported by MODIS surface reflectance data显示文摘The high spatial resolution and temporal observation frequency of HJ-1/CCD make it suitable for aerosol monitoring.However,because of the lack of a shortwave infrared band,it is difficult to use HJ-1/CCD imagery to retrieve aerosol optical depth(AOD).We developed a new algorithm for HJ-1/CCD AOD retrieval by introducing MODIS surface reflectance outputs(MOD09) as support.In this algorithm HJ-1/CCD blue band surface reflectance was retrieved through MOD09 blue band surface reflectance by band matching of the two sensors.AOD at 550 nm was then generated through a pre-calculated look-up table for HJ-1/CCD.Eighteen HJ-1/CCD images covering the Jing-Jin-Tang(Beijing-Tianjin-Tangshan) region were used to retrieve AOD using the new algorithm,and the AODs were then validated using AERONET ground measurements in Beijing and Xianghe.The validation shows that compared with AERONET ground measurements,27/29 AODs have error less than 0.1 in absolute value. | SUN Lin1,2,SUN ChangKui1,LIU QinHuo2 & ZHONG Bo2 1Geomatics College,Shandong University of Science and Technology,Qingdao 266510,China 2State Key Laboratory of Remote Sensing Science,Chinese Academy of Sciences,Beijing 100101,China | 2010 | Science China Earth Sciences2010，53，S1： | 14 |
| 4 | Influence of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific on the inter-decadal variations of the stratosphere-troposphere exchange of water vapor显示文摘This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of 1958-2001.The climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water vapor.The analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early 1990s.In these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South China Sea was gradually weakening,while the role of the WNP becomes more and more important.Further studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor exchange.The thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 years.Their synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and regions.Especially after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor exchange.Results have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(emission) on global climate. | ZHAN RuiFen1,2&LI JianPing2 1Shanghai Typhoon Institute of China Meteorological Administration,Shanghai 200030,China 2State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China | 2008 | Science China Earth Sciences2008，51，8： | 11 |
| 5 | High time resolution observation and statistical analysis of atmospheric light extinction properties and the chemical speciation of fine particulates显示文摘In recent years,the visibility deterioration caused by regional fine particulate pollution becomes one of the crucial air pollution problems in the urban areas of our country.The rapid variation of visibility and fine particulates make it difficult to estimate the relationship between them precisely and accurately unless high time resolution observation data can be accessed.This study aims to fill this gap in the field of atmospheric science by establishing a formula using multiple linear regressions.Excellent fitting goodness (R2=0.913,n=3167) was obtained using 10 min average of high-resolution real-time light scattering coefficients,light absorption coefficients,main chemical speciation concentration in PM1 and some meteorological parameters from 17 Jan to 16 Feb,2009.It shows that the average light extinction coefficient during the observation in the winter of Shenzhen was measured to be 290 ± 183 Mm?1,consisting of 72% of light scattering and 21% of absorption.In terms of the percentage contribution of PM1 chemical species to the total light extinction,the organic matter was estimated to be most with an average of 45%,followed by ammonium sulfate with an average of 24%.The contributions of black carbon and ammonium nitrate were 17% and 12%,respectively.Besides,the diurnal variation of light extinction was investigated as well in this study. | YAO TingTing1,HUANG XiaoFeng1,HE LingYan1,HU Min2,SUN TianLe1,XUE Lian1,LIN Yun1,ZENG LiWu1 & ZHANG YuanHang2 1Key Laboratory for Urban Habitat Environmental Science and Technology,School of Environment and Energy,Peking University Shenzhen Graduate School,Shenzhen 518055,China 2State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China | 2010 | Science China Chemistry2010，53，8： | 10 |
| 6 | Alkylation mechanism of benzene with 1-dodecene catalyzed by Et_3NHCl-AlCl_3显示文摘The isotope exchange method was employed to investigate the catalytic mechanism of ionic liquid in alkylation of benzenes with olefins.It is proposed that alkylation was induced by the Lewis acid AlCl3 which attracted π electrons of 1-dodecene to shift toward 1-carbon,thus forming a carbonium ion.The carbonium ion further reacted with benzenes to form a complex.Due to unstabilit of the complex,a deuterated ring proton was transferred into an electronegative 1-carbon of the side chain to substitute for the AlCl3,accordingly 2-phenyldodecane was generated. | QI GuoPeng 1,JIANG Feng 1,SUN XueWen 2 & ZHAO SuoQi 2 1School of Chemical Engineering,Tianjin University,Tianjin 300072,China 2State key Laboratory of Heavy Oil Processing,Petroleum University of China,Beijing 102249,China | 2010 | Science China Chemistry2010，53，5： | 7 |
| 7 | Microstructures and characteristics of deep trap levels in ZnO varistors doped with Y_2O_3显示文摘In this paper discussions on ZnO based varistor ceramics doped with different ratios of Y2O3 are presented.Analysis on the phase and microstructures of the samples indicates that an additional phase is detected in the samples doped with Y2O3,and the average grain size of the specimens decreases from about 9.2μm to 4.5μm,with an increase in the addition of Y2O3 from 0 mol%to 3 mol%.The corresponding varistor’s voltage gradient markedly increases from 462 V/mm to 2340 V/mm,while the nonlinear coefficient decreases from 22.3 to 11.5,respectively.Furthermore,the characteristics of deep trap levels in these ZnO samples are investigated by measuring their dielectric spectroscopies.The trap energy level and capture cross section evaluated by relaxation peak of the Cole-Cole plot vary slightly as the addition of Y2O3 increases.These traps may be ascribed to the intrinsic defects of ZnO lattice. | LIU Jun 1 ,HU Jun 1 ,HE JinLiang 1 ,LIN YuanHua 2 &LONG WangCheng 1 1State Key Laboratory of Power Systems,Department of Electrical Engineering,Tsinghua University,Beijing 100084,China 2State Key Laboratory of New Ceramics and Fine Processing,Department of Material Science and Engineering,Tsinghua University, Beijing 100084,China | 2009 | Science China(Technological Sciences)2009，52，12： | 5 |
| 8 | Convergence for Imaginary Time Step evolution in the Fermi and Dirac seas显示文摘The convergence for the Imaginary Time Step (ITS) evolution with time step is investigated by performing the ITS evolution for the Schrdinger-like equation and the charge-conjugate Schrdinger-like equation deduced from Dirac equation for the single proton levels of 12C in both the Fermi and Dirac seas. For the guaranteed convergence of the ITS evolution to the 'exact' results,the time step should be smaller than a 'critical' time step Δtc for a given single-particle level. The 'critical' time step Δtc is more sensitive to the quantum numbers |κ| than to the energy of the single-particle level. For the single-particle levels with the same κ,their 'critical' time steps are in the same order. For the single-particle levels with similar energy,a relatively small (large) 'critical' time step for larger (smaller) |κ| is needed. These conclusions can be used in the future self-consistent calculation to optimize the evolution procedure. | LI FangQiong1,ZHANG Ying2 & MENG Jie2,3,4 1Guizhou University for Nationalities,Guiyang 550025,China 2State Key Lab Nucl. Phys. & Tech.,School of Physics,Peking University,Beijing 100871,China 3School of Physics and Nuclear Energy Engineering,Beihang University,Beijing 100191,China 4Department of Physics,University of Stellenbosch,Stellenbosch,South Africa | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，2： | 4 |
| 9 | Density functional theory study of 1:1 glycine–water complexes in the gas phase and in solution显示文摘We present a systematic study of 1:1 glycine-water complexes involving all possible glycine conformers. The complex geometries are fully optimized for the first time both in the gas phase and in solution using three DFT methods (B3LYP, PBE1PBE, X3LYP) and the MP2 method. We calculate the G3 energies and use them as the reference data to gauge hydrogen bond strength in the gas phase. The solvent effects are treated via the integral equation formalism-polarizable continuum model (IEF-PCM). Altogether, we locate fifty-two unique nonionized (N) structures and six zwitterionic (Z) structures in the gas phase, and fifty-five N structures and thirteen Z structures in solution. Both correlation and solvation are shown to be important in geometry determination. We found that in the gas phase, a water molecule binds more strongly to the carboxylic acid group of glycine than to its amine group, whereas in solution phase the reverse is true. The most stable Z structure is isoenergetic with the most stable N structure. | KE HongWei1, RAO Li2, XU Xin2* & YAN YiJing1* 1Department of Chemistry, Hong Kong University of Science and Technology, Kowloon, Hong Kong, China 2State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, Xiamen University, Xiamen 361005, China | 2010 | Science China Chemistry2010，53，2： | 4 |
| 10 | The structural analysis of fuzzy measures显示文摘From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an'isotropism'assumption.Under this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2)the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3)the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy measures.The results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures. | ZHANG Ling1,ZHANG Bo2 & ZHANG YanPing1 1 Computer Science College,Anhui University,Hefei 230039,China 2State Key Lab of Intelligent Technology & Systems Tsinghua National Lab for Information Science & Technology Information Science & Technology College,Computer Science & Technology,Tsinghua University,Beijing 100084,China | 2011 | Science China(Information Sciences)2011，54，1： | 3 |
| 11 | Concentration and distribution of 17 organochlorine pesticides (OCPs) in seawater from the Japan Sea northward to the Arctic Ocean显示文摘Seventeen classic organochlorine pesticides in surface seawater were studied in terms of their composition pattern as well as their distribution pattern in the areas covering the Japan Sea,Okhotsk Sea,Bering Sea,Chukchi Sea and Arctic Ocean.Their concentrations varied,but roughly two levels were seen with one ranging between 0.1 and 1 ng L-1 for most HCH isomers and the other lower than 0.1 ng L-1 for other chemicals.Of the 17 target compounds,HCHs were dominant with a total concentration percentage generally more than 50%,and a relatively high concentration percentage of heptachlor and aldrine was also observed at scattered stations.The historical long-term trend of several target chemicals in the five sea zones considered was discussed in comparison with previous reports.Inter-sea zone comparison was carried out for individual chemicals by comparing the concentration variation in all five sea zones.A higher variation in concentration was generally found in the northern sea zones,namely the Bering Sea,Chukchi Sea and Arctic Ocean,for most target compounds.The sum concentration of the 17 target chemicals displayed a general trend of increasing northward from the Japan Sea to the Okhotsk Sea to the Bering Sea to the Arctic Ocean.Different latitudinal trends were found forγ-HCH andγ-HCH,and the reason of this difference was discussed by considering their divergence of thermodynamic properties,which could contribute to a slightly different fractionation effect during their northward transport driven by atmospheric long range transport.The source of the HCHs was identified by analyzing theγ-HCH/γ-HCH ratio,which was less than 4 without exception,indicating a component characteristic featuring a mixture of technical HCHs and lindane.In addition,the vertical distribution ofγ-HCH,γ-HCH and their ratio at station B80 was discussed.Different patterns were found in the upper 300 m while in layers from 300 m downward to 3500 m the patterns were fairly comparable.The vertical profiles were used to correlate the water mass distribution,based on which four layers were tentatively classified at station B80. | CAI MingGang 1,2,QIU CanRong 1,SHEN Yuan 1,CAI MingHong 3,HUANG ShuiYing 1,QIAN BiHua 1,SUN JiongHui 1 & LIU XiaoYan 1 1Department of Oceanography,College of Oceanography and Environmental Science,Xiamen University,Xiamen 361005,China 2State Key Laboratory of Marine Environmental Science,Xiamen University,Xiamen 361005,China 3State Oceanic Administration Key Laboratory for Polar Science,Polar Research Institute of China,Shanghai 200136,China | 2010 | Science China Chemistry2010，53，5： | 3 |
| 12 | Analytical method of Cr stable isotope and its application to water pollution survey显示文摘High Cr(VI) concentration is a potential serious risk to environment and ecologic system.Thus,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this paper.Based on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are established.Eleven samples collected around a chemical factory in Hubei Province were analyzed by this technique.These samples showδ53Cr values ranging from-1.7‰to 7.3‰and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53Cr value and its extent of Cr contamination.This study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water system.It is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation. | GAO YongJuan 1,2,3,MA Teng 4,5,LING WenLi 1,2,LIU CunFu 4,5 & LI Li 4,5 1Faculty of Earth Science,China University of Geosciences,Wuhan 430074,China 2State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China 3 Graduate School,China University of Geosciences,Wuhan 430074,China 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(China University of Geosciences) ,Wuhan 430074,China 5 Sino-Hungary Joint Laboratory of Environmental Sciences and Health,China University of Geosciences,Wuhan 430074,China | 2010 | Chinese Science Bulletin2010，55，7： | 3 |
| 13 | PrP mutants with different numbers of octarepeat sequences are more susceptible to the oxidative stress显示文摘One of the physiological functions of cellular prion protein(PrP C )is believed to work as a cellular resistance to oxidative stress,in which the octarepeats region within PrP plays an important role.However,the detailed mechanism is less clear.In this study,the expressing plasmids of wild-type PrP (PrP-PG5)and various PrP mutants containing 0(PrP-PG0),9(PrP-PG9)and 12(PrP-PG12)octarepeats were generated and PrP proteins were expressed both in E.coli and in mammalian cells.Protein aggregation and formation of carbonyl groups were clearly seen in the recombinant PrPs expressed from E.coli after treatment of H2O2.MTT and trypan blue staining assays revealed that the cells expressing the mutated PrPs within octarepeats are less viable than the cells expressing wild-type PrP.Statistically significant high levels of intracellular free radicals and low levels of glutathione peroxidase were observed in the cells transfected with plasmids containing deleted or inserted octarepeats.Remarkably more productions of carbonyl groups were detected in the cells expressing PrPs with deleted and inserted octarepeats after exposing to H2O2.Furthermore,cells expressing wild-type PrP showed stronger resistant activity to the challenge of H2O2 at certain extent than the mutated PrPs and mock. These data provided the evidences that the octarepeats number within PrP is critical for maintaining its activity of antioxidation.Loss of its protective function against oxidative stress may be one of the possible pathways for the mutated PrPs to involve in the pathogenesis of familial Creutzfeldt-Jacob diseases. | AN Run1 ,2,DONG ChenFang 2,LEI YanJun 1,2,HAN Lu 2,LI Ping 2,CHEN JianMing 2,WANG GuiRong 2, SHI Qi 2 ,GAO Chen 2 ,JIANG HuiYing 2 ,ZHOU Wei 2 ,HAN Jun 2 ,CHU YongLie 1 ,DONG XiaoPing 2 1School of Medicine,Xi’an JiaoTong University,Xi’an 710061,China 2State Key Laboratory for Infectious Disease Prevention and Control,National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention,YingXin Rd 100,Beijing 100052,China | 2008 | Science China(Life Sciences)2008，51，7： | 3 |
| 14 | Effect of slow monomer addition on molecular parameters of hyperbranched polymers synthesized in the presence of multifunctional core molecules显示文摘This study develops the kinetics for the slow monomer addition technique in the synthesis of hyperbranched polymers. Taking the conversion of monomer (x) as a variable, we derived the analytic expressions of molecular size distribution function, average degree of polymerization, polydispersity index and degree of branching. These expressions are not only amenable to the polymerization with high monomer conversion, but also appropriate to describe the whole polymerization process. Comparison with the one-pot polymerization indicates that the slow monomer addition technique improves the molecular weight distribution and increases the degree of branching for the products obtained. | ZHOU ZhiPing1, Jia ZhengWei1 & YAN DeYue2 1School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China 2State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China | 2010 | Science China Chemistry2010，53，4： | 3 |
| 15 | Experiments and sensitivity analyses for heat transfer in a meter-scale regularly fractured granite model with water flow显示文摘Experiments of saturated water flow and heat transfer were conducted for a meter-scale model of regularly fractured granite.The fractured rock model(height 1502.5 mm,width 904 mm,and thickness 300 mm),embedded with two vertical and two horizontal fractures of pre-set apertures,was constructed using 18 pieces of intact granite.The granite was taken from a site currently being investigated for a high-level nuclear waste repository in China.The experiments involved different heat source temperatures and vertical water fluxes in the embedded fractures either open or filled with sand.A finite difference scheme and computer code for calculation of water flow and heat transfer in regularly fractured rocks was developed,verified against both the experimental data and calculations from the TOUGH2 code,and employed for parametric sensitivity analyses.The experiments revealed that,among other things,the temperature distribution was influenced by water flow in the fractures,especially the water flow in the vertical fracture adjacent to the heat source,and that the heat conduction between the neighboring rock blocks in the model with sand-filled fractures was enhanced by the sand,with larger range of influence of the heat source and longer time for approaching asymptotic steady-state than those of the model with open fractures.The temperatures from the experiments were in general slightly smaller than those from the numerical calculations,probably due to the fact that a certain amount of outward heat transfer at the model perimeter was unavoidable in the experiments.The parametric sensitivity analyses indicated that the temperature distribution was highly sensitive to water flow in the fractures,and the water temperature in the vertical fracture adjacent to the heat source was rather insensitive to water flow in other fractures. | Wei LU1,2,Yan-yong XIANG1 (1School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China) (2State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China) | 2012 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2012，13，12： | 2 |
| 16 | Multi-carbazole derivatives for two-photon absorption data storage:Synthesis,optical properties and theoretical calculation显示文摘Two novel quadrupolar organic compounds, 3-(4-((E)-2-(9-butyl-9H-carbazol-6-yl) vinyl)styryl)-9-propyl-9H-carbazole (BCSPC) and 3-(3-(3-((1E)-2-(4-((E)-2-(3-(3,5-bis(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazol-6-yl)vinyl)phenyl) vinyl)-9-butyl-9H-carbazol-6-yl)-5-(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazole (BCPBC), with different conjugated arms, have been designed and synthesized. Their one-and two-photon absorption (TPA) and excited fluorescence properties have been experimentally investigated. The two-photon absorption cross-sections of two compounds were estimated by two-photon excited fluorescence technique using 200 fs, 76 MHz, Ti:sapphire laser, which are 22 and 154 GM for BCSPC and BCPBC, respectively. The optimal excitation wavelengths are 780 nm for both BCSPC and BCPBC. A data recording experiment proved the potential application of the materials. | LI Lin1, YANG JiaXiang1,2, WANG CaiXia1, HU ZhangJun1, TIAN YuPeng1,2, LI Jing3, WANG ChuanKui3, LI Ming4, CHENG GuangHua4, TANG HuoHong5, HUANG WenHao5, TAO XuTang2 & JIANG MinHua2 1Department of Chemistry, Anhui University, Hefei 230039, China 2State Key Laboratory of Crystal Materials, Institute of Crystal Materials of Shandong University, Jinan 250100, China 3Department of Physics, Shandong Normal University, Jinan 250014, China 4State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China 5Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026, China | 2010 | Science China Chemistry2010，53，4： | 2 |
| 17 | Zinc-prolinamide complex catalyzed direct asymmetric aldol reactions in the presence of water显示文摘An efficient direct asymmetric aldol reaction with zinc triflate and prolinamides as combined catalysts is reported.A series of chiral prolinamides have been designed and used in the direct aldol reaction resulting in the desired products with excellent yields(up to 94% yield) and high enantioselectivities(up to 96% ee).Water was found to play a significant role in the formation of the aldol products,which suggests a new strategy in the design of new organic catalysts. | LU ZhiJin1,MEI HaiBo1,ZHANG GuangQian1,HAN JianLin1* & PAN Yi1,2* 1School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210093,China 2State Key Laboratory of Coordination Chemistry Nanjing University,Nanjing 210093,China | 2010 | Science China Chemistry2010，53，11： | 1 |
| 18 | Incompatibility behavior of a symbiotic plasmid pMH7653Rb in Mesorhizobium huakuii 7653R显示文摘Mesorhizobium huakuii strain 7653R harbored two indigenous plasmids named pMH7653Ra and pMH7653Rb.The larger plasmid pMH7653Rb (symbiotic plasmid) was transferred to M.huakuii HN308SR harboring three plasmids: pMHHN308a,pMHHN308b and pMHHN308c,and HN3015SR harboring three plasmids: pMHHN3015a,pMHHN3015b and pMHHN3015c by tri-parent mating.Two stable indigenous plasmids,pMHHN308b and pMHHN308c of HN308SR,were co-eliminated due to the introduction of pMH7653Rb,and the transconjugant was named HN308SRN14.The results implied that pMH7653Rb and pMHHN308b,pMHHN308c were incompatible and might have been ascribed to the same incompatible group.The plasmid profiles of transconjugant HN3015SRN14 showed that the second largest plasmid pMHHN3015b of HN3015SR was cured due to the introduction of pMH7653Rb.The results also implied that pMH7653Rb and pMHHN3015b were incompatible.Results from plant nodulation tests showed that pMH7653Rb could only maintain the nodulation ability in transconjugant HN308SRN14 and its nodule number was more than that of wild strain HN308SR,but could not replace the nitrogen fixation effect of pMHHN308b and pMHHN308c.The plasmid cured mutant HN308SRN14D harboring only pMHHN308a formed null nodules that demonstrated pMHHN308a was relevant to nodulation ability.HN3015SRN14 harboring pMH7653Rb,pMHHN3015a and pMHHN3015c formed null nodules while HN3015SRN14D containing pMHHN3015a and pMHHN3015c lost the nodulation ability.The plasmid replication repC-like gene sequences were detected by a polymerase chain reaction from 7653R,HN308,HN3015,HN308SRN14 and HN3015SRN14.The repC gene sequence similarities of the strains tested attained 99%. | HU GuoYuan1,LI WeiWei1 & ZHOU JunChu2 1Key Laboratory for Green Chemical Process of Ministry of Education,Wuhan Institute of Technology,Wuhan 430073,China 2State Key Laboratory of Agricultural Microbiology,Huazhong Agricultural University,Wuhan 430070,China | 2010 | Science China(Life Sciences)2010，53，6： | 1 |
| 19 | Chronic morphine treatment decreases acoustic startle response and prepulse inhibition in rats显示文摘The reward-related effects of addictive drugs primarily act via the dopamine system, which also plays an important role in sensorimotor gating. The mesolimbic dopamine system is the common pathway of drug addiction and sensorimotor gating. However, the way in which addictive drugs affect sensorimotor gating is currently unclear. In previous studies, we examined the effects of morphine treatment on sensory gating in the hippocampus. The present study investigated the effects of morphine on sensorimotor gating in rats during chronic morphine treatment and withdrawal. Rats were examined during treatment with morphine for 10 successive days, followed by a withdrawal period. Acoustic startle responses to a single startle stimulus (115 dB SPL) and prepulse inhibition responses were recorded. The results showed that acoustic startle responses were attenuated during morphine treatment, but not during withdrawal. PPI was impaired in the last 2 morphine treatment days, but returned to a normal level during withdrawal. | MENG ZhiQiang1,3, ZHOU DongMing1,2, WANG JianHong1 & MA YuanYe1,2 1State Key Laboratory of Brain and Cognitive Science, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China 2State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China 3Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2010 | Science China(Life Sciences)2010，53，11： | 1 |
| 20 | Study on specific interaction of new ferrocene-substituted carborane conjugates with hemoglobin protein显示文摘The interactions between the new organometallic complexes, ferrocene-substituted dithio-o-carborane conjugates (denoted as FcSB1, FcSB2 and FcSBCO) and hemoglobin (Hb) are investigated by electrochemistry, fluorescence and UV-vis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H2O/O2 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state (oxygenated conformation, relax) to T state (deoxygenated conformation, tense). The binding affinity is in the order of FcSBCO>FcSB2>FcSB1. Moreover, the fluorescence study illustrates that the three ferrocene-carborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the β37Trp residue which is located on the α1β2 interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the protein-binding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs. | WU ChunHui1,3, YE HongDe2, JIANG Hui1, WANG XueMei1 & YAN Hong2 1State Key Lab of Bioelectronics (Chien-Shiung Wu Lab), Southeast University, Nanjing 210096, China 2State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China 3School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China | 2012 | Science China Chemistry2012，55，4： | 1 |
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