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| 1 | Local Structure Determination of Mn^(2+)-Doped Fluoride Crystals by Superhyperfine Splitting Measurements显示文摘A procedure is presented for the calculation of the Mn^(2+)-F^(-) bond length from the superhyperfine constants measured by magnetic resonance experiments.With the present technique it is possible to detect the variation of the bond length,ΔR,down to 0.01Å.The technique is sensitive enough to determine the bond length R and its variationΔR experienced when pressure or temperature changes. | 赵敏光 | 1998 | Chinese Physics Letters1998，15，1： | 16 |
| 2 | THE STRUCTURE OF ARMILLARIZIN,A NEW PROTOILLUDANE SESQUITERPENOID AROMATIC ESTER FROM ARMILLARIA MELLEA(VAHL.EX FR)QUEL.显示文摘A new protoilludane sesquiterpenoid aromatic ester,named armillarizin(1)has been isolated from the artificially cultured mycelium of Armillaria me-llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on the ba-sis of spectral analyses.The relative configuration was established from thenuclear Overhauser effects and from the values of ~1H-~1H coupling constants. | Jun Shan YANG Ya Lun SU Yu Lan WANG Xiao Zhang FENG De Quan YU Xiao Tian LIANG Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing,100050 | 1990 | Chinese Chemical Letters1990，1，2： | 8 |
| 3 | Best Constants for Moser-Trudinger Inequalities,Fundamental Solutions and One-Parameter Representation Formulas on Groups of Heisenberg Type | COHN William S. | 2002 | Acta Mathematica Sinica,English Series2002，18，2： | 8 |
| 4 | Influence of microwave treatment on mechanical behaviour of compact basalts under different confining pressures显示文摘The realisation of microwave-induced fracturing of hard rocks has potential signiflcance for microwave-assisted mechanical rock fracturing and stress release in deep rock masses.In this context,compact basalts were treated by microwave heating in a multi-mode cavity at a frequency of 2450 MHz,and then,we investigated the mechanical behaviour of basalt samples after microwave treatment under uniaxial compression and conventional triaxial compression(CTC)tests.After microwave exposure,cracks appeared on the surface and inside of the rock sample,and the temperature of the sample's surface was unevenly distributed.The results show that the conventional triaxial compressive strength(CTCS)of basalt samples decreased linearly with microwave exposure time,and the higher the confining pressure,the smaller the reduction in the strength of basalt samples after microwave treatment.Under uniaxial compression,microwave exposure greatly affected the axial deformation,suggesting that deformation resistance of the samples gradually decreases with increasing microwave exposure time.Under triaxial compression,some microcracks induced by microwave exposure closed due to the effect of confining pressure,resulting in the confining pressure inhibiting any rightward shift of the axial deformation curve.Furthermore,under uniaxial compression,the elastic modulus and Poisson's ratio of basalts also decreased in a quasi-linear manner with elapsed microwave exposure time.Under triaxial compression,microwave exposure has slight influence on elastic modulus and Poisson's ratio.After microwave treatment,the changes in rock strength and deformation mainly result from changes in between the mineral structures.Confining pressure results in the closure of microcracks produced by microwave exposure,so that effects of microwave treatment on strength and deformation decrease,thus reducing the influence on elastic constants.The cohesion decreases with increasing microwave exposure time and shows an approximately linear decrease over time.In the basalt samples,new microcracks in various directions generated by microwave exposure can increase the discreteness of test results,while the discreteness of test results caused by microcracks gradually reduces with increasing confining pressure. | Gaoming Lu Xiating Feng Yuanhui Li Xiwei Zhang | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，2： | 7 |
| 5 | THE PREDATOR-PREY MODEL WITH TWO LIMIT CYCLES显示文摘This paper investigates the predator-prey system:x=k1(x-ax)-k(x)y,y=(-k3+βk(x)ywit.k(x)=k2x, x≤x, k2x, x>τ,where α, β, τ; k1, k2, k3 are positive constants.The main results are as follows(i) In case k3-βk2τ≥0 system (1) has no limit cycle.(ii) In case k3-βk2τ<0, k1+k3-βk2τ>0, and for O<α<<1, system (1) at least has two limitcycles. | 任永泰 韩莉 | 1989 | Acta Mathematicae Applicatae Sinica1989，5，1： | 5 |
| 6 | Effect of thermo-mechanical treatment on mechanical and elastic properties of Ti–36Nb–5Zr alloy显示文摘The evolutions of phase constitutions and mechanical properties of a β-phase Ti–36Nb–5Zr(wt%) alloy during thermo-mechanical treatment were investigated. The alloy consisted of dual(β t α″) phase and exhibited a double yielding phenomenon in solution treated state. After cold rolling and subsequent annealing at 698 K for 20 min, an excellent combination of high strength(833 MPa) and low modulus(46 GPa) was obtained. The high strength can be attributed to high density of dislocations, nanosized α phase and grain refinement. On the other hand, the low Young's modulus originates from the suppression of chemical stabilization of β phase during annealing, which guarantees the low β-phase stability. Furthermore, the single-crystal elastic constants of the annealed Ti–36Nb–5Zr alloy were extracted from polycrystalline alloy using an in-situ synchrotron X-ray technique. The results indicated that the low shear modulus C44 contributes to the low Young's modulus for the Ti–36Nb–5Zr alloy, suggesting that reducing C44 through thermo-mechanical treatment might be an efficient approach to realize low Young's modulus in β-phase Ti alloys. The results achieved in this study could be helpful to elucidate the origin of low modulus and sheds light on developing novel biomedical Ti alloys with both low modulus and high strength. | Qingkun Meng Qing Liu Shun Guo Yongqi Zhu Xinqing Zhao | 2015 | Progress in Natural Science:Materials International2015，25，3： | 5 |
| 7 | Seasonal dependency of controlling factors on the phytoplankton production in Taihu Lake, China显示文摘In this study, 44 profiles of gross primary productivity(GPP) and sunlight, along with water temperature, Chlorophyll-a(Chla) and nutrients, were observed in Meiliang Bay of Taihu Lake, China, in the spring, summer, and fall seasons. Effects of water temperature, light,and nutrient concentration were examined in relation to the GPP-unit-Chla(GPP of algae per Chla). The results showed that the optimum temperature for the GPP of phytoplankton was 27.9°C, the optimal PNA-unit-Chla(photon number absorbed by phytoplankton per Chla) was 0.25(mol), and the HSCN-unit-Chla and HSCP-unit-Chla(half-saturation constants of nitrogen and phosphorus of algae per Chla) were 0.005(mg/L) and 0.0004(mg/L), respectively. The seasonal dependency of the effect of different factors on the GPP was analyzed. Compared with temperature and nutrients, light was found to be the most important factor affecting the GPP during the three seasons. The effect of temperature and nutrients on the GPP of phytoplankton has obvious seasonal change. In spring, temperature was the secondary factor affecting the GPP of phytoplankton, and the effect of nutrients may be negligible in the eutrophic lake on account of temperature limit, which showed that the GPP of algae was only affected by the physical process. In summer and fall, temperature didn't affect the GPP of algae, and the presence of nutrients was the secondary factor affecting the GPP of phytoplankton. From summer to fall, effect of phosphorus was weakened and effect of nitrogen was enhanced. | Qiaohua Zhao Jing Wang Jianjian Wang Julian X.L.Wang | 2019 | Journal of Environmental Sciences2019，31，2： | 4 |
| 8 | The influence of impurity on the critical thickness of the CeO_2 buffer layer for coated conductors显示文摘The lattice parameters, band structure, density of state and elastic constant of RE-doped CeO2 (RE=Sm, Gd, Dy), the buffer material for coated HTS conductors, are calculated using the plane-wave method with pseudopotentials based on the density functional theory (DFT) of first-principle. The rule and mechanism of the effect of rare earth impurity on the critical thickness of the CeO2 buffer layer are investigated. It is found that, in the range of the calculation, the changes of the lattice volume V and elastic constant E of CeO2 with the impurity are mainly determined by the increased electrons ne of the system. The relationship of the elastic constant E and increased electrons ne is established. It is indicated that the critical thickness of the CeO2 single buffer layer doped with Sm, Gd, and Dy may be enhanced by 22%, 43% and 33%, respectively. | PAN Min1, HUANG Zheng2, MA HuanFeng2, QIANG WeiRong2, WEI LianFu1, WANG Long2 & ZHAO Yong1,3 1 Key Laboratory of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education of China), Superconductivity R&D Center (SRDC), Southwest Jiaotong University, Chengdu 610031, China 2 School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China 3 Superconductivity Research Group, School of Materials Science and Engineering, University of New South Wale, Sydney, 2052 NSW, Australia | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，7： | 3 |
| 9 | Equilibrium dialysis of metal-serum albumin (Ⅱ)——Allosteric effect in Ni(Ⅱ)-serum albumin systems显示文摘Detailed studies were carried out on equilibrium dialysis of the binding of Ni2++ ion to human scrum albumin (HSA) and bovine serum albumin (BSA).The successive stability constants were obtained by the Icfisi squares fitting.The eight binding sites found for both Ni(Ⅱ)-HSA and Ni(Ⅱ)-BSA systems can be divided into two different sets; and for both systems,there exist two identical prior binding sites where the bound Ni2+ ions can he con sidered as allosteric effectors,which induce the allosteric effect in accordance with the model proposed by Moeod et al As indicated by allosteric parameters,the ability of R-state to bind Ni2+ ions is ca 100 times as much as that of T state,and the conformation of HSA is markedly tenser than that of BSA. | 胡绪英 宋仲容 苏宪东 欧阳砥 黄杰生 周永洽 | 1997 | Science China Chemistry1997，40，2： | 3 |
| 10 | A methodology to determine the elastic properties of anisotropic rocks from a single uniaxial compression test显示文摘This paper introduces a new methodology to measure the elastic constants of transversely isotropic rocks from a single uniaxial compression test.We first give the mathematical proof that a uniaxial compression test provides only four independent strain equations.As a result,the exact determination of all five independent elastic constants from only one test is not possible.An approximate determination of the Young’s moduli and the Poisson’s ratios is however practical and efficient when adding the Saint-Venant relation as the fifth equation.Explicit formulae are then developed to calculate both secant and tangent definitions of the five elastic constants from a minimum of four strain measurements.The results of this new methodology applied on three granitic samples demonstrate a significant stress-induced nonlinear behavior,where the tangent moduli increase by a factor of three to four when the rock is loaded up to 20 MPa.The static elastic constants obtained from the uniaxial compression test are also found to be significantly smaller than the dynamic ones obtained from the ultrasonic measurements. | Morteza Nejati Marie Luise Texas Dambly Martin OSaar | 2019 | Journal of Rock Mechanics and Geotechnical Engineering2019，11，6： | 3 |
| 11 | Nonlinear Acoustics of Bounded Solid-Reflection and Refraction of Second-Order Bulk Waves(Ⅱ)——SV- or SH- Wave Incidence显示文摘In the case of SV- or SH-wave oblique incidence,the reflection and refraction of the second-order bulk waves resulting from a plane boundary between two solid media are investigated and the mathematical expressions of them are given.It is shown that an SH-wave incidence is absolutely necessary to an overall knowledge of the relationship between the TOEs for isotropic solid.The importance of both contributions of the nonaccumulation waves and the effects of the boundary surface are indicated by numerical computation. | 钱祖文 | 1994 | Science China Mathematics1994，37，6： | 3 |
| 12 | CONVERGENCE SYSTEMS AND STRONG CONSISTENCY OF LEAST SQUARES ESTIMATES IN REGRESSION MODELS显示文摘Consider the multiple regression model yi=β1xi1+…+βpxip+ei i=1, 2,…, (1) where xij are known constants, β1, …,βp are unknown parameters, and ei. are unobservable random variables. Throughout the sequel let Xn denote the design matrix (xij)1≤i≤,1≤j≤p, and let Yn=(y1,…, yn)’, and β=(β1,…,βp)’. For n≥p, | 陈桂景 黎子良 魏庆荣 | 1983 | Chinese Science Bulletin1983，28，1： | 2 |
| 13 | Structural and optical properties of Cr doped ZnO crystalline thin films deposited by reactive electron beam evaporation technique显示文摘ZnO and Cr-doped ZnO thin films are grown on to glass substrates using reactive electron beam(e-beam) evaporation technique.Variation of structural,morphological,and optical properties with Cr doping is investigated.X-ray diffraction(XRD) studies show that the films are polycrystalline in nature with single phase.Energy dispersive spectroscopy(EDS) results demonstrate that Cr ions are substitutionally incorporated into ZnO.Atomic force microscopy(AFM) reveals that the films present a compact surface and root mean squared(RMS) roughness increased with Cr contents.The optical band gap energy Eg of the films has been determined using Transmission data by spectrophotometer and ellipsometry.The band gap energy found to be decreased with increasing Cr doping concentration.The optical constants(refractive index,extinction coefficient) are calculated using ellipsometry and found to increase with Cr doping concentration. | Amjid Iqbal Arshad Mahmood Taj Muhammad Khan Ejaz Ahmed | 2013 | Progress in Natural Science:Materials International2013，23，1： | 2 |
| 14 | Determination of pKa values of alendronate sodium in aqueous solution by piecewise linear regression based on acid-base potentiometric titration显示文摘As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments. | Jing Ke Hanfei Dou Ximin Zhang Dushimabararezi Serge Uhagaze Xiali Ding Yuming Dong | 2016 | Journal of Pharmaceutical Analysis2016，6，6： | 2 |
| 15 | Oxidation of estrone by permanganate: Reaction kinetics and estrogenicity removal显示文摘Permanganate was used as an oxidant to control estrone in the present study. Kinetics was determined at pH 2.5-9.4 and temperature 15–40°C for the reaction of estrone with potassium permanganate. It was found that the reaction is second-order overall and first-order with respect to both estrone and permanganate. The second-order rate constant for the reaction at pH 5.8 and 25°C is 44.45 L mol-1 s-1. The reaction rate first decreased with the increase of pH in the range of 2.5-6.6 and then increased greatly with the increase of pH in the range of 6.6-9.4. In addition, the rate constant exponentially increased with the increase of reaction temperature. Removal of estrogenicity was also investigated during the degradation of estrone using yeast estrogen screen (YES). Results show that the estrogenicity increased in the initial 15 min of reaction and then decreased fast, with a removal rate of 73.8% within the 30 min of reaction. Results also demonstrate that the reaction rate between estrone and permanganate is faster in natural water background than in the ultra-pure water system. Permanganate oxidation is therefore a feasible option for removal of estrone in drinking water treatment processes. However, the contact time must be enough in order to remove estrone without causing the increase of estrogenicity. | XiaoLing Shao Jun Ma Gang Wen JingJing Yang | 2010 | Chinese Science Bulletin2010，55，9： | 2 |
| 16 | Synthesis of AgGa1-xInxSe2 Polycrystalline Materials显示文摘AgGa1-xInxSe2 polycrystals were synthesized by the method of mechanical oscillation and temperature oscillation. X-ray diffraction spectra of polycrystal powder are conformable with the JCPDS cards. Lattice constants a and c calculated from the XRD were found to obey Vegard's law. The melting point of AgGa0.8In0.2Se2 obtained by means of differential scanning calorimetry (DSC) is 796.53 ℃. The DSC curve also show that there are no other transformation points below the melting point. The results indicate that polycrystalline materials synthesized by the method mentioned above are high-quality and can be used to grow single crystals by the vertical Bridgman technology. | Liu Juan Zhao Beijun Zhu Shifu Huang Yi Zhang Jianjun Zhu Weilin Xu Chengfu Chen Baojun Li Ming He Zhiyu | 2006 | Journal of Rare Earths2006，24，z1： | 2 |
| 17 | Strain engineering of electro-optic constants in ferroelectric materials显示文摘Electro-optic effects allow control of the ow of light using electric fields,and are of utmost importance for today’s information and communication technologies,such as TV displays and fiber optics.The search for large electro-optic constants in films is essential to the miniaturization and increased efficiency of electro-optic devices.In this work,we demonstrate that strain-engineering in PbTiO_(3) films allows to selectively choose which electro-optic constant to improve.Unclamped electro-optic constants larger than 100 pm V^(−1) are predicted,either by driving the softening of an optical phonon mode at a phase transition boundary under tensile strain,or by generating the equivalent of a negative pressure via compressive strain to obtain large piezoelectric constants.In particular,a r_(13) electro-optic coefficient twice as large as the one of the commonly used LiNbO_(3) electro-optic material is found here when growing PbTiO_(3) on the technologicallyimportant Si substrate. | Charles Paillard Sergei Prokhorenko Laurent Bellaiche | 2019 | npj Computational Materials2019，，1： | 2 |
| 18 | MICELLAR CATALYSIS-THE KINETICS OF Ni(Ⅱ)AND PYRIDYLAZO DYES COMPLEX FORMATION IN THE PRESENCE OF SODIUM DODECYL SULFATE MICELLES显示文摘By means of the Stopped—Flow Spectrophotometry,the kinetics of the reactions betweennickel(Ⅱ)and the ligand 5—bromopyridylazo diethylaminophenol(5-BrPADAP)and 3,5—dibromopyridylazo diethylaminophenol(3,5—2BrPADAP)have been investigated in themicellar solution of sodium dodecyl sulfate(SDS).The reaction rate(compared with thatmeasured in aqueous solution for the same Ni2+concentration)was enhanced up to a factorof 400.Kinetic analysis indicates that the rate enhancement can be explained in terms of theconcentration effect of the micelles on the rcactants(i.e.partitioning coefficient effects).Aquantitative expression for the rate enhancement is derived,using the psudo—phase modeland Berezin’s original micellar-catalysis coneepts.The influenccs of hydrophobic character-istics of ligands on the micellar-catalysis effect have been studied also. | Chen Yaohong, Pan Weizeng (Department of Chemistry, Sichuan University,Chengdu, China) | 1989 | 分子催化1989，3，S1： | 2 |
| 19 | BCKLUND TRANSFORMATIONS FOR THE ISOSPECTRAL AND NON-ISOSPECTRAL KdV HIERARCHIES显示文摘In the following we assume that u(x, t) is a smooth function of x and t, and u( x, t ) and its derivatives of any order with respect to x tend to zero rapidly as x→-∞. | 田畴 张友金 | 1990 | Chinese Science Bulletin1990，35，20： | 2 |
| 20 | Binding equilibrium study between Mn( Ⅱ ) and HSA or BSA显示文摘The binding of Mn( Ⅱ ) to human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by equilibrium dialysis at physiological pH (7. 43). The Scatchard analysis indicates that there are 1.8 and 1.9 strong binding sites of Mn( Ⅱ ) in HSA and BSA, respectively. The successive stability constants which are reported for the first time are obtained by non-linear least-squares methods fitting Bjerrum formula. For both Mn( Ⅱ )-HSA and Mn( Ⅱ )-BSA systems, the order of magnitude of K1 was found to be 104. The analyses of Hill plots and free energy coupling show that the positive cooperative effect was found in both Mn( Ⅱ )-HSA and Mn( Ⅱ )-BSA systems . The results of Mn ( Ⅱ ) competing with Cu ( Ⅱ ) 、 Zn(Ⅱ)、Cd( Ⅱ) or Ca( Ⅱ ) to bind to HSA or BSA further support the conjecture that there are two strong binding sites of Mn( Ⅱ) in both HSA and BSA. One is most probably located at the tripeptide segment of N- terminal sequence of HSA and BSA molecules involving four groups composed of | 梁宏 涂楚桥 张宏志 沈星灿 周永洽 申泮文 | 2000 | Chinese Journal of Chemistry2000，18，1： | 2 |
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