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51.
枸橼酸莫沙必利的合成 总被引:1,自引:0,他引:1
分别以邻羟基对氨基苯甲醇钠,对氟苯甲醛,邻苯二甲酰亚胺为起始原料,制得3个中间体,用其中2个中间体经偶合,环化后与第3个中间体反应,再经成盐制得产品,其摩尔总收率为31.5%。 相似文献
52.
Differential scanning calorimetry (DSC) and x-ray diffraction (XRD) are employed to investigate the effects of nickel on the crystallization of the amorphous Zr70Cu20Ni10 alloy. We have found that the crystallization process of the amorphous Zr70Cu20Ni10 alloy is strongly influenced by the addition of nickel. Addition of 10 at% Ni to the Zr70Cu30 amorphous alloy makes the crystallization process proceed from a single-stage mode to a double-stage mode. The activation energy for crystallization of the amorphous Zr70Cu20Ni10 alloy is calculated to be about 388kJ·mol-1 on the basis of the Kissinger equation. The effects of nickel on the crystallization of the amorphous Zr70Cu20Ni10 alloy are discussed in terms of the genetics of metals. 相似文献
53.
The He1 photoelectron (PE) spectra of both 2(5H) furanone and itstrans-chair-dimeric-compound (t-c-DFN) are reported. The assignment of the PES bands is made on the basis of band shapes, the PES results of the molecules
which have the similar atomic groups, and the restricted Hartree-Fock (RHF) calculations for the molecules studied. From the
results of both PES experimental and theoretical calculations, it is proved that the ionization potential (IPS) of the HOMO
for the dimeric-compound is lower than that of the HOMO for the monomer. And the total energy computed for thet-c-DFN is the lowest in the four possible configurations of dimeric-compounds of 2(5H) furanone. Therefore the synthesis oft-c-DFN is also the easiest.
Project supported by the National Natural Science Foundation of China. 相似文献
54.
E. V. Voronina E. P. Yelsukov A. V. Korolyov A. E. Yelsukova 《Hyperfine Interactions》2006,168(1-3):1079-1083
The experimental data from Mössbauer spectroscopy and magnetic measurements are presented as functions of the temperature and external magnetic field for a B2-type ordered Fe 66 Al 34 alloy. 相似文献
55.
We study the phase diagram of the strongly interacting matter at finite temperatures and densities including 2SC, uniform chiral and non-uniform chiral phases within the Nambu–Jona-Lasinio model in the mean field approximation. 相似文献
56.
57.
Agnès Tourin 《Numerische Mathematik》1992,62(1):75-85
Summary The reconstruction from a shaded image of a Lambertian and not self-shadowing surface illuminated by a single distant pointwise light source may be written as a first-order Hamilton-Jacobi equation.In this paper, we continue the investigation begun in E. Rouy and A. Tourin into the uniqueness of the solution of this equation; the approach is based on the viscosity solutions theory and the dynamic programming principle.More precisely, we concentrate here on the uniqueness of the viscosity solution of this equation in case the measured luminous intensity reflected by the surface is discontinuous along a smooth curve. We prove a general comparison result for a piecewise Lipschitz continuous Hamiltonian and illustrate it by numerical experiments. 相似文献
58.
系列类立方烷型Fe4S4簇合物的XPS分析 总被引:1,自引:0,他引:1
对7种类立方烷型Fe_4S_4簇合物进行了XPS分析,得到了中心离子Fe的价态,给出了系列Fe_4S_4中骨架硫的结合能,由峰合成结果给出各种S、N的比例与按结构式计算的结果相同。 相似文献
59.
铜、锌在5-Br-PADAP和表面活性剂体系中的分光光度法同时测定 总被引:1,自引:0,他引:1
5一Br—PADAP在阳离子表面活性剂溴代十六烷基三甲胺存在下同时测定Cu^2 和Zn^2 ,找出最佳实验条件,对水和血清测定结果令人满意. 相似文献
60.
Peng Ping Wenshou Wang Xuesi Chen Xiabin Jing 《Journal of Polymer Science.Polymer Physics》2007,45(5):557-570
Poly(ε‐caprolactone)‐based segmented polyurethanes (PCLUs) were prepared from poly(ε‐caprolactone) diol, diisocyanates (DI), and 1,4‐butanediol. The DIs used were 4,4′‐diphenylmethane diisocyanate (MDI), 2,4‐toluenediisocyanate (TDI), isophorone diisocyanate (IPDI), and hexamethylene diisocyanate (HDI). Differential scanning calorimetry, small‐angle X‐ray scattering, and dynamic mechanical analysis were employed to characterize the two‐phase structures of all PCLUs. It was found that HDI‐ and MDI‐based PCLUs had higher degree of microphase separation than did IPDI‐ and TDI‐based PCLUs, which was primarily due to the crystallization of HDI‐ and MDI‐based hard‐segments. As a result, the HDI‐based PCLU exhibited the highest recovery force up to 6 MPa and slowest stress relaxation with increasing temperature. Besides, it was found that the partial damage in hard‐segment domains during the sample deformation was responsible for the incomplete shape‐recovery of PCLUs after the first deformation, but the damage did not develop during the subsequent deformation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 557–570, 2007 相似文献