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Heat capacity and thermodynamical properties of the crystal of [RE_2(Glu)_2(H_2O)_8](ClO_4)_4·H_2O (RE = Nd, Eu, Dy)

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science china Chemistry 2009年第7期52卷 862-867页

作者： wu XinMin1, LI Wei1, TAN ZhiCheng2 & QU SongSheng3 1 department of Chemical Engineering, beijing Institute of Petro-chemical technology, beijing 102617, china 2 Thermochemistry Laboratory, Dalian Institute of Chemical physics, Chinese Academy of sciences, Dalian 116023, china 3 College of Chemistry and Molecular science, wuhan university, wuhan 430072, china department of Chemical Engineering Beijing Institute of Petro-chemical Technology Beijing 102617 China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China College of Chemistry and Molecular science Wuhan University Wuhan 430072 China

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K.

关键词： complex of rare earth, [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy Glu = glutamic acid), low-temperature heat capacity, standard enthalpy of formation

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THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

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Chinese Journal of Polymer science 2003年第2期21卷 117-122页

作者： Chi wu The Open Laboratory of Bond Selective Chemistry department of Chemical physics, university of science and technology of china, Hefei 230026 china department of Chemistry The Chinese university of Hong Kong Shatin, Hong Kong Univ Sci & Technol china Dept Chem Phys Open Lab Bond Select Chem Anhua 230026 Peoples R China Chinese Univ Hong Kong Dept Chem Sha Tin Hong Kong Peoples R China

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute *** formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.

关键词： Viscoelasticity Mesoglobular phase Heteropolymer Nanoparticle Polymer Dispersion Microphase inversion

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Behavior of gravity waves with limited amplitude in the vicinity of critical layer

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Chinese science Bulletin 2002年第18期47卷 1547-1550页

作者： wu Shaoping & Yl Fanwuhan Institute of physics and Mathematics, Chinese Academy of sciences, wuhan 430071, china department of Radio science and technology, wuhan university, wuhan 430072, china department of physics, Huazhong Normal Univ wuhan Institute of physics and Mathematics Chinese Academy of Sciences Wuhan China department of physics Huazhong Normal University Wuhan China department of Radio science and technology Wuhan University Wuhan China

By using the FICE scheme, a numerical simulation of three-dimensional nonlinear propagation of gravity wave packet in a wind-stratified atmosphere is presented. The whole nonlinear propagation process of the gravity wave packet is shown; the propagation behavior of gravity waves in the vicinity of critical layer is analyzed. The results show that gravity waves encounter the critical layer when propagating in the fair winds whose velocities increase with height, and the height of critical layer propagating nonlinearly is lower than that expected by the linear gravity waves theory; the amplitudes of gravity waves increase with height as a whole before gravity waves encounter the critical layer, but the increasing extent is smaller than the result given by the linear theory of gravity waves, while the amplitudes of gravity waves reduce when gravity waves meet the critical layer; the energy of wave decreases with height, especially at the critical layer; the vertical wavelength reduces with the height

关键词： gravity waves critical layer FICE scheme simulation.

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Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, wu Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2 & ZHAO Guiwen3 1. College of Life sciences, Suzhou Universty, Suzhou 215006, china 2. Synchrotron Radiation Laboratory, Institute of High Energy physics, The Chinese Academy of science, beijing 100039, china 3. Chemical department, university of science and technology of china, Hefei 230026, china 1. College of Life sciences Suzhou Universty 215006 Suzhou China 2. Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science 100039 Beijing China 3. Chemical department University of Science and Technology of China 230026 Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—25 –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

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Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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science china(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2,wu Jian2,XUE Zhen2,XU ZiZong2,HU Tao3,WANG YiFang3 & WANG XiaoLian2 1 College of Material science and technology,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china 2 department of Modern physics,university of science and technology of china,Hefei 230026,china 3 Institute of High Energy physics,Chinese Academy of sciences,beijing 100049,china College of Material science and technology Nanjing University of Aeronautics and Astronautics Nanjing China department of Modern physics University of Science and Technology of China Hefei China Institute of High Energy physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(beijing Electron Positron Collider,china).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

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Scanning near-field acoustic microscope and its application

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science china(Technological sciences) 2011年第1期54卷 126-130页

作者： XU ping,CAI Wei & WANG RongMing Key Laboratory of Micro-nano Measurement-Manipulation and physics (Ministry of Education) department of physics,Beihang university,beijing 100191,china 1. Key Laboratory of Micro-nano Measurement-Manipulation and physics (Ministry of Education) department of physics Beihang University Beijing 100191 China

Scanning near-field acoustic microscope （SNAM） combines the ultrasonic detection technology with scanning near-field microscopy. The main characteristic of such microscope is that the acoustic wave is produced or detected in near-field area whether ultrasonic transducer acts as generator or detector. The resolution of SNAM can reach to nanometer scale. First, two typical SNAMs, scanning electron acoustic Inicroscope and scanning probe acoustic microscope, will be introduced in this paper. The working principle of our homemade SNAM based on a commercial scanning probe microscope will be reported, together with some recent results from this homemade SNAM.

关键词： scanning near-field acoustic microscope ultrasonic detection technology scanning probe microscopy

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Binary population synthesis study of the supersoft X-ray phase of single degenerate type Ia supernova progenitors

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Research in Astronomy and Astrophysics 2011年第8期11卷 965-973页

作者： Xiang-Cun Meng wu-Ming Yang school of physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China department of Astronomy Beijing Normal University Beijing 100875 China

In the single degenerate （SD） scenario for type Ia supernovae （SNe Ia）, a mass-accreting white dwarf is expected to experience a supersoft X-ray source （SSS） phase. However, some recent observations showed that the expected number of massaccreting WDs is much lower than that predicted from theory, regardless of whether they are in spiral or elliptical galaxies. In this paper, we performed a binary population synthesis study on the relative duration of the SSS phase to their whole mass-increasing phase of WDs leading to SNe Ia. We found that for about 40% of the progenitor systems, the relative duration is shorter than 2% and the evolution of the mean relative duration shows that it is always smaller than 5%, both for young and old SNe Ia. In addition, before the SNe Ia explosions, more than 55% of the progenitor systems were experiencing a dwarf novae phase and no more than 10% were staying in the SSS phase. These results are consistent with the recent observations and imply that both in early- and late-type galaxies, only a small fraction of mass-accreting WDs resulting in SNe Ia contributes to the supersoft X-ray flux. So, although our results are not directly related to the X-ray output of the SN Ia progenitor, the low supersoft X- ray luminosity observed in early type galaxies may not be able to exclude the validity of the SD model. On the contrary, it is evidence to support the SD scenario.

关键词： stars: white dwarfs -- stars: supernovae: general

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Intense Photoluminescence and Movement of Optical Absorption Edge in Alumina Aerogels

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Journal of Materials science & technology 2000年第3期16卷 315-318页

作者： Xianting SUN, Lianzeng YAO, Chimei MO, Gang SHI, Weili CAI and Yimin ZHANG (department of Materials science and Engineering, university of science and technology of china, Hefei 230026, china) Lide ZHANG (Institute of Solid State physics, Chinese Academy department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China department of physics Teacher's College of Ping Ding Shan China Institute of Solid State physics Chinese Academy of Sciences Hefei 230031 China

Alumina aerogels with high porosity of nanometer size were prepared from Al, n-butanol and ethyl acetoacetate by the sol-gel route and the N2 supercritical extraction drying technique. Optical experiment results showed that for alumina aerogels after annealing at 500℃ for 4 h one intense blue emission band appeared in the wavelength range of 400 to 800 nm, and the optical absorption edge moved from 8.0 eV of coarse grain Al203 to 3～eV and with increasing the annealing temperature, this luminescence band presented blue shifts. The reasons of these new optical properties are discussed in detail.

关键词： Aerogels

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Two-dimensional conjugated coordination polymer monolayer as anode material for lithium-ion batteries:A DFT study

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Chinese Chemical Letters 2024年第6期35卷 180-184页

作者： Xin-Tong Zhao Jin-Zhi Guo Wen-Liang Li Jing-ping Zhang Xing-Long wu MOE Key Laboratory for UV Light-Emitting Materials and technology Northeast Normal UniversityChangchun 130024China Faculty of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhou 341000China

Nowadays,lithium-ion batteries(LIBs)play a crucial role in modern society in the aspect of portable electronic devices and large-scale smart ***,the current performance of lithium-ion batteries has been unable to meet the growing expectations of society and scientific ***,we have synthetically investigated availability of 2D Ni-TABQ monolayer as anode based on DFT for LIBs *** findings have demonstrated that 2D Ni-TABQ monolayer is a semiconductor with a small band gap of 0.2 eV,which suggest that the electronic property of 2D Ni-TABQ monolayer would take place an evident shift from semiconductor property to metallic property after Li ***,we checked the stability of 2D Ni-TABQ monolayer and investigated the viability of exfoliation from bulk multilayer Ni-TABQ to form 2D Ni-TABQ monolayer in the light of exfoliation energy and binding *** continuously studied electrochemical properties of 2D Ni-TABQ monolayer with respect of theoretical specific capacity,Li-ion diffusion barriers and open-circuit *** the charging process,2D Ni-TABQ monolayer can achieve a high specific capacity of 722 m Ah/g with an open-circuit voltage range from 1.12 V to 0.22 *** aforementioned results make the 2D Ni-TABQ monolayer a promising anode for LIBs.

关键词： The first principles Density functional theory Lithium-ion battery Anode material Two-dimensional material

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Predictors of Adverse Pregnancy Outcomes Following Traumatic Injuries

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Current Medical science 2024年第3期44卷 642-647页

作者： Wan-rong LU ping wu Gong SONG Mei-qi GU Zhe XU Li HE National Clinical Research Center for Gynecology and Obstetrics Cancer Biology Research CenterTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China department of Traumatic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective After traumatic injury in pregnant women,providing timely and appropriate management for high-risk patients is crucial for both pregnant women and *** study aimed to identify risk factors that predict adverse pregnancy outcomes after traumatic *** A retrospective cohort study including 317 pregnant patients who experienced trauma was *** collected data included general demographics,injury mechanisms and adverse pregnancy *** were divided into two subgroups based on the absence or presence of trauma-related adverse pregnancy *** and multivariate logistic regressions were conducted to estimate the associations between clinical variables and adverse pregnancy *** A total of 41(12.93%)patients experienced adverse pregnancy outcomes within the first 24 h *** study revealed that age>35 years(OR=14.995,95%CI:5.024–44.755,P<0.001),third trimester trauma(OR=3.878,95%CI:1.343–11.204,P=0.012),abdominal pain(OR=3.032,95%CI:1.221–7.527,P=0.017),vaginal bleeding(OR=3.226,95%CI:1.093–9.523,P=0.034),positive scan in focused assessment with sonography for trauma(FAST)positive(OR=8.496,95%CI:2.825–25.555,P<0.001),9≤injury severity score(ISS)<16(OR=3.039,95%CI:1.046–8.835,P=0.041)and ISS≥16(OR=5.553,95%CI:1.387–22.225,P=0.015)increased the probability of posttraumatic adverse pregnancy *** age,gestational age at delivery,vaginal bleeding and positive FAST results were risk factors for abnormal *** Advanced maternal age,third trimester,and positive FAST results should alert multidisciplinary trauma teams to closely monitor patients to prevent adverse pregnancy outcomes.

关键词： adverse pregnancy outcomes predictive factors abnormal delivery trauma

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