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101.
Chemical structure of immature sulfur-rich kerogen and composition of immature sulfur-rich crude oil in Jianghun oil field
have been studied. In molecular level, crude oil differs from thermolysed and chemolysed products of kerogen but does resemble
the bitumen in immature sulfur-rich source rock. Therefore, immature sulfur-rich oil may be derived from the expelling of
bitumen rather than from thermal cracking of kerogen. 相似文献
102.
An energy theory is proposed on the buckling of a ferromagnetic thin plate in a transverse static magnetic field. The analytic
solution of critical field for plates is obtained by using variational method. It is shown that the critical magnetic field
is not only influenced by the ratio of the thickness to the length, but also by the width, total length and the magnetic susceptibility
of the specimen. Theoretical calculations agree with experiments reasonably. 相似文献
103.
Colony-stimulating factor-1 (CSF-1), which is necessary for cell proliferation and differentiation, regulates both immediate
and delayed early responses throughout G1 phase. The binding of CSF-1 to its receptor (CSF-1R) triggers phosphorylation of
the receptor and its intrinsic tyrosine kinase. The activated receptor binds directly to cytoplasmic effector proteins, which
induce multiple-signal transduction pathways. CSF-1 can induce the c-myc gene expression via Ras and Ets-related proteins.
The expression of c-fos/jun family genes is also targeted following the activation of Ras. CSF-1R activates STAT1 and STAT3
to participate in signaling, but JAKs do not appear to contribute to signaling by CSF-1R. CSF-1R activates PI3-kinase, and
PI3-ki can interact with downstream proteins by the MAPKK-related pathway independent of Ras/Raf. PC-PLC can enforce signaling
in response to CSF-1. Furthermore, the turnover and dephosphorylation by the phosphatase SHPTP1 of CSF-1R are the major mechanism
in the negative regulation of signaling by CSF-1R 相似文献
104.
Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains 总被引:1,自引:0,他引:1
This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results
place constraints on the degree of crust-mantle interaction during the UHP metamorphism. 相似文献
105.
SrGa2S4: Ce blue TFEL device with a novel structure was prepared by electron beam evaporation. The dielectric constant of insulator
layer in this structure is far less than that in the conventional structure, so the hot-electrons can be accelerated in SiO2 layers. The stable TFEL with good chromaticity was achieved and the basic characteristics were investigated. 相似文献
106.
The plagioclase amphibolites from Kuokesu area, Kuruktag, Xinjiang occur as enclaves embedded in the granodioritic gneiss. In the light of major elements and REE data, the parent rocks of the plagioclase amphibolites belong to weak_alkaline basalts. Their Nd model ages mainly range from 2 832 to 3 075 Ma. The seven plagioclase amphibolites yield a reasonable good isochron age of (828±86) Ma(2σ) with I Nd =0.510 981±82, ε Nd ( t )=-11.5±1.6. Such a case shows the existence of great proportion of the Archaean mafic crustal basement on the Kuokesu area. The strong tectonic_thermal event at about 820 Ma made the Sm_Nd isotope of the metamorphic rocks homogenization. This event would be associated with the Tarim Movement. 相似文献
107.
用于智能材料与结构的NiTi丝的电阻特性研究 总被引:5,自引:0,他引:5
研究了拉伸过程中,NiTi形状记忆合金丝的应变与电阻的关系.结果表明,对于初始组织为马氏体的NiTi丝,在拉伸过程中,电阻与应变之间成线性关系.对于初始组织为奥氏体或奥氏马氏体两者混合的NiTi丝,当发生应力诱发马氏体相变后,曲线的斜率降低,相变前后电阻-应变保持线性关系.对于初始组织含有R相组织的NiTi丝,在拉伸过程中,电阻的变化规律较为复杂,取决于初始组织中各相的比例和温度.在卸载阶段,当没有相变过程发生时,电阻-应变之间呈线性关系;当有相变过程发生时,电阻-应变曲线的斜率会发生改变. 相似文献
108.
(H,G)—变换和拟正则半群 总被引:1,自引:0,他引:1
郑神州 《上海交通大学学报》1998,32(3):116-119
研究一般的(H,G)型变换通过适当合成变换后生成拟正则半群;并建立了G-变换和(H,G)型变换两者之间的拟共形共轭关系.对于给定的一个拟正则半群,构造了一个不变共形结构GΓ,使得该半群中的每个元素在这个不变共形结构下保持G-变换不变. 相似文献
109.
It was found that C60Br24 transforms to C60 spontaneously in some solvents. The intermediate, C60Br8, can be separated in some cases. When the bromine trap, phenol, was added,p-bromophenol and other brominated product were obtained and identified. The influences of time, the kind of solvent, etc were
investigated. Possible mechanism was suggested.
Supported by the National Natural Science Foundation of China
Liu Ying: born in 1969, Ph. D 相似文献
110.
具有公共对称面的两个二次回转面的相贯线 总被引:1,自引:0,他引:1
本文论述了常见的两个二次回转面轴线相交和平等时,其相贯线在公共对称面(投影面)的投影分别为双曲线和抛物线,只有在特殊情况下是直线,椭圆和圆,并举例说明在计算机上绘图的方法。 相似文献