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1.
Background
Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH. 相似文献2.
<正>A series of phthalonitrile blending resins were prepared from 4-aminophenoxyphthalonitrile(APN) and 4,4'-bis(3,4- dicyanophenoxy)biphenyl(BPH) by directly powder-mixing and copolymerization.Differential scanning calorimeter(DSC) and dynamic rheology were used to study the curing reaction behaviors of APN/BPH blends,and the results indicated that the introduction of APN accelerated the curing rate of BPH,and the existence of BPH decreased the curing temperature of APN/BPH systems.The thermal stability of postcured APN/BPH resins was investigated by thermogravimetric analysis(TGA),and the TGA results indicated that the crosslinked polymers of APN/BPH systems possessed good thermal stability. 相似文献
3.
This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90. 相似文献
4.
现代力学中的现代数学方法 总被引:1,自引:0,他引:1
本文简要介绍了力学与数学再次结合趋势的历史背景和现状。根据当代科学技术向力学提出的问题,简要综述了现代力学所涉及的现代数学领域和方法. 相似文献
5.
Gholamabbas Chehardoli Mohammad Ali Zolfigol Seyedeh Bahareh Azimi Ebadollah Alizadeh 《中国化学快报》2011,22(7):827-830
Melamine and poly vinylpyrrolidone(PVP) reacted with neat sulfuric acid readily to form two new organic solid acids namely melamine-(H2SO4)3 and PVP-(H2SO4)n.These solid acids were used for the first nitration of bisphenol A as well as other phenols in the presence of NH4NO3.Mono- and di-nitro bisphenol A have been characterized with IR and 1H NMR techniques. 相似文献
6.
Nathan A. Branch Ghatu Subhash Nagaraj K. Arakere Michael A. Klecka 《International Journal of Solids and Structures》2011,48(3-4):584-591
A new reverse analysis is presented that determines the plastic response of both nongraded and plastically graded materials (PGMs) without the need for traditional tension or compression tests. The method utilizes the concepts of expanding cavity model for strain hardening materials, Tabor’s rule of converting Vickers hardness to flow stress, representative plastic strain induced by indentation, and finite element modeling of the macro indentation process. A unique flow curve is determined when the experimentally measured increase in micro Vickers hardness matches that predicted by the proposed method within the plastic zone of a macro Vickers indent. The method is validated for a nongraded stainless steel first and then extended to determine the gradient in flow curves of plastically graded, case-hardened M50 NiL material, a widely used bearing steel. Such knowledge of the plastic response of the case hardened region will help optimize the design of case hardened bearings with longer rolling contact fatigue life and higher thrust load capabilities. 相似文献
7.
Lihua Chen Dept.of Math. Computer Science Fuqing Branch of Fujian Normal University Fuqing Fujian Jiaqi Mo Dept.of Math. Anhui Normal University Wuhu Anhui Faculty of Science Huzhou Teacher College Huzhou Zhejiang 《Annals of Differential Equations》2011,(4):434-439
An initial boundary value problem of semilinear nonlocal reaction diffusion equations is considered.Under some suitable conditions,using the asymptotic theory,the existence and asymptotic behavior of the interior layer solution to the initial boundary value problem are studied. 相似文献
8.
李献华 《中国科学B辑(英文版)》1991,(5)
Single-grain zircon U-Pb analyses, combined with Sm--Nd, Rb--Sr, K--Ar and ~(40)Ar-~(39)Ar datingresults, suggest that there are four magmatic periods in Wanyangshan--Zhuguangshan granitoidbatholith, i.e. late Caledonian (414--434 Ma), Indosinian (220 Ma), middle Yanshanian (155 Ma)and late Yanshanian (105 Ma). The tectonic movement characterized by the unconformablecontact between Mid--Devonian and Pre--Devonian occurred about 380 Ma ago. Magmation istightly related to the regional crustal movement. 相似文献
9.
FU De-Gang WANG Guo-Xiong TANG Wen-XiaState Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu ChinaYU Kai-BeiAnalysis center Chengdu Branch of Chinese Academy of Science Chengdu China 《中国化学》1994,(1)
A new μ3-O triiron(Ⅲ) complex [Fe_3O(OBz)_6(CH_3OH)_3](NO_3)(CH_3OH)_2 (HOBZ = benzoic acid) has been synthesized, its structure has been determined and variable temperature magnetic susceptility has also been measured. In the molecule, three iron atoms formed an equilateral triangle with u_3-O in center. The fitting to the magnetic susceptibility showed that an intramolecular antiferromagnetic exchange interaction occurred between iron atoms with J=-25.51 cm~(-1), and a weaker intermolecular antiferromagnetic exchange interaction occurred with zJ' = -2.30cm~(-1). 相似文献
10.