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11.
庞丹阳叶沿林 江栋兴郑涛王全进 李智焕李湘庆葛愉成 吴翠娥张高龙 胡青元王佳 A.Ozawa Y.Yamaguchi R.Kanungo D.Fang I.Tanihata 《中国物理快报》2004,21(11):2151-2154
The differential cross sections of quasielastic scattering of a 25 MeV/u ^6He from ^9Be target have been measured.The double-folding model approach is applied to generate the real part of the optical potential. The imaginary potential parameters as well as some of the real potential parameters are studied in comparison with the experimental data. The effect of the unstable nucleus is discussed. 相似文献
12.
风力发电机组变速恒频控制系统研究 总被引:2,自引:0,他引:2
全面介绍了一种最新应用于风力发电中的新型电机—无刷双馈电机,并分析了这种新型电机作变速恒频运行的原理并对这种电机进行了动态特性仿真研究,给出了形式简洁的控制方程和易于实现的控制方案。 相似文献
13.
Pan Yifei Department of Mathematical Sciences Indiana University-Purdue University Fort Wayne Fort Wayne IN - U.S.A. School of Mathematics Informatics Jiangxi Normal University Nanchang China 《中国科学A辑(英文版)》2005,48(Z1)
It is proved that every proper holomorphic self-map of a smooth bounded Reinhardt domain of D'Angelo finite type in Cn (n > 1) is an automorphism. 相似文献
14.
1.INTRODUCTION[()-227.3()]Endotoxinislipopolysaccharide(LPS)derivedfromthecellmembranesofgram-negativebacteria.Endotoxincancausefebrilereactionsinanimalswithsymptomsofhighfever,vasodilation,diarrheaandfetalshockwheninjectedeveninaverysmallamount[1].Iftheconcentrationofendotoxininpatients?bloodishighenoughitcancauseseveresepsis,whichisamajorcauseofdeathinpatientsandcontinuestohaveahighmortalitydespiteappropriatesurgery,potentantibiotic,andintensivesupportivetherapy[2~5].LipidAisthemaintox… 相似文献
15.
达草灭对莱茵衣藻(Chlamydomonas reinhardtii) 品系遗传后效应的研究 总被引:1,自引:0,他引:1
通过将莱菌衣藻(Chlamydomonas reinhardtii)6种达草灭抗性突变株分别与野生型株、丧失合成叶绿素b能力的cbnI-43等基因突变株和精氨酸依赖型突变株杂交对其后代进行四分析与随机分析,发现在Nfr-4-Nfr-7突变株中达草灭抗性状只有单一核基因遗传的性质,而在Nfr-1、Nfr-3~Nfr-7抗性株的抗性性状都是由同一个nfr-1基因(norflurazon resisanse)的突变所决定的,而Nfr-4抗性株的抗性性状是由另一滚突变等位基因nfr-2所决定的。在Nfr-1和Nfr-3抗性株中除了nfr-1基因的突变还有nfr-3基因突变的参与。 相似文献
16.
A.R.ELAMROUSS 《数学学报(英文版)》2005,21(1):129-142
This paper contains a generalization of the well-known Palais-Smale and Cerami compactness conditions. The compactness condition introduced is used to prove some general existence theorems for critical points. Some applications are given to differential equations. 相似文献
17.
Electron Spin Resonance Studies of Mn^2+ in Freshwater Snail Shells: Pomacea Canaliculata Lamarck and Fossilized Snail Shell 下载免费PDF全文
N.Udomkan S.Meejoo P.Limsuwan P.Winotai Y.Chaimanee 《中国物理快报》2005,22(7):1780-1783
We study paramagnetic Mn^2 ions present in the nowadays shells of univalve freshwater snails of Pomacea canaliculata lamarck (PCL) and the fossilized freshwater snail (FFS), Viviparus. All these shells are abundant in Thailand. The PCL shells were ground into fine powder. A set of seven samples were then separately annealed for 2 h in air atmosphere at different annealing temperatures while the FFS powder was characterized as-received. The PCL shells mainly consist of aragonite and a fraction of calcite. The heat treatments of the PCL powder samples at temperature higher than 450℃ resulted in an irreversible phase transformation from aragonite to calcite. However, it is found that the FFS shell is mainly made of calcite, with a minor fraction of aragonite. The crystal structure of the high-temperature-annealed PCL samples are quite similar to that of FFS, which indicates that the metamorphosis (aragonite→calcite) in the FFS shell had occurred but was not yet completed, although it had remained under the pressure and temperature of the Earth‘s crusts over millions of years. Our detailed ESR spectral analyses of PCL and FFS show that Mn^2 ions enter the Ca^2 sites during a biomineralization process. Simulated ESR parameters of PCL-500 of Mn^2 at a uniaxial site of calcite are reported. It is surprising to And that the ratio of Mn^2 concentration present in FFS to those in PCL shells evaluated from ESR spectra is as much as 10:1. 相似文献
18.
用闪光蒸镀法在77K制备了NdxFe1-x(x=0.06-0.80)非晶薄膜,原位测定了其电阻随温度的变化。结果表明:在0.192和ρ(T)∝T。晶化不是在一个固定的温度,而是在一个温度区间发生。 相似文献
19.
The electrochemical oxidation of 1, 3-benzenedithiol was investigated in a 0. 100 mol/L tetrabutylammonium perchlorate/acetonitrile electrolyte. The electrochemical techniques used were potential sweep, bulk electrolysis, rotating disc and the potential step method. The combination of the techniques yielded the number of electrons transferred per molecule, the reaction order, the transfer coefficient, the diffusion coefficient and concentration of dithiol anions, the standard heterogeneous rate constant as well as the formal potential and equilibrium constant of the preceeding dissociation reaction. This paper also illustrates the methods for studying the electrode kinetics of reactions which (a) involve a chemical reaction preceeding the electron-transfer process, (b) have insoluble polymer products, and (c) are totally irreversible. 相似文献
20.
Md. Naziruddin Khan A. S. AI-Dwayyan Z. H. Zaidi 《中国物理快报》2006,23(9):2407-2410
Chrysene and 1.2-benzanthracene are successfully doped in a solid wax film and their vibrational spectra in gooo--400cm^-1 are discussed. The harmonic frequencies and relative intensities of both the molecules observed in the film are compared with theoretical values calculated by the density functional theory (DFT) model as well as with the previous experimental data. The effects on spectra due to change of matrix and some additional bands observed in the wax film are also reported. Excellent agreement in the spectral positions and strengths between the experiments and DFT values are found. 相似文献