The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras

The realization and siructure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras over the complex field C are given.     

Origin of immature sulfur-rich oil in Jianghan oil field

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.     

A continuous 200-ka palaeoclimatic record from stalagmite in Tangshan Cave, Nanjing

An oxygen isotope temperature record from 381 to 166 kaB. P. (²³⁰Th/²³⁴U dating and tuned ages) has been obtained by combining data on the isotopic composition of calcites with that of fluid inclusions trapped in a stalagmite from a limestone cave in which a fossil cranium deposited. Several laminae in microsequence of the stalagmite represent climatic events or shifts. The Nanjing man fossil was older than 381 kaB. P.     

Cloning, construction of prokaryotic expression vector and expression ofEscherichia coli cytosine deaminase gene

Cytosine deaminase gene ofEscherichia coli strain H-30 was cloned, and its initiation codon of ‘GTG’ was mutated to ‘ATG’ by PCR. Prokaryotic recombinant expression vector pBV220-CD was constructed. Clone with high enzyme activity were selected by detecting their specific activity of cytosine deaminase. 5-FC(5-FC, 5-fluorocytosine) could induce the lethal toxicity to cells containing active CD gene. DNA sequence analysis indicated that there were 16 altered bases and 5 of them resulted in the alteration of amino acids in predicted peptide by comparing DNA sequence of the clone H-30-CD-11 with high enzyme activity with CD gene reported in Gene Bank.     

Diamond synthesis from a system of chromium-carbide and Ni70Mn25Co5 alloy

In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2 powder and Ni 70Mn 25Co 5 alloy in weight ratio of 1∶6 was treated under 6 0 GPa and 1 500℃ for 20, 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2 decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated.     

Relationship between giant magnetoresistance of NiFe/Cu multilayers and their microstructures

The (111)-orientated NiFe/Cu multilayers were prepared by magnetron sputtering method. At room temperature, saturation magnetoresistances of NiFe/CU multilayers oscillate as a function of Cu spacer layer thickness. Two peak GMR values of 19.4%, 11.6% and 11.2%, 1% appear, respectively, at Cu sublayer thickness of t_Cu,= 1.0, 2.2 nm while the deposition pressures are 0.25 and 0.45 Pa. X-ray small-angle reflections and diffuse scattering at Cu K-edge (8.979 keV) by synchrotron radiation source were used to characterize the interfacial roughness. Diffraction anomalous fine-structure scattering (DAFS) was performed to investigate the local structure of NiFe and Cu sublayers. Results show that the deposition pressure has effect on interfacial roughness of the samples obviously, and the interfacial roughness also affects the GMR values of the samples strongly.     

支持CAD／CAPP／CAM集成和并行的制造特征

由于设计和制造过程的复杂性,目前还没有一种有效的方法能彻底解决产品设计、制造和生产管理等生命周期内各个阶段的信息集成问题．探讨了并行工程下的ＣＡＤ／ＣＡＰＰ／ＣＡＭ的集成框架,提出了支持ＣＡＤ／ＣＡＰＰ／ＣＡＭ集成和并行运行的制造特征,并在商品化ＣＡＤ／ＣＡＭ软件ＵＧⅡ上进行了开发工作．该系统已通过纺织行业箱体、柴油机行业的油泵以及机床厂的主轴箱等多种零件考核．     

1673K下BaO-BaF_2-Cr_2O_3渣系的热力学性质

１６７３Ｋ下,采用－ＭｏＣｒ＋Ｃｒ２Ｏ３ＺｒＯ２（ＭｇＯ）｛Ｃｕ＋Ｃｒ｝ａｌｏｙ＋（Ｃｒ２Ｏ３）ｓｌａｇＭｏ＋固体电解质电池测定了ＢａＯＢａＦ２Ｃｒ２Ｏ３渣系中Ｃｒ２Ｏ３的活度．研究结果表明,Ｃｒ２Ｏ３的活度随其浓度升高而升高,随ＸＢａＯ／ＸＢａＦ２升高而降低．根据实验及Ｘ射线衍射结果推测了该渣系的等温相图,并作出了该渣系中Ｃｒ２Ｏ３的等活度图．     

吸收比-系数倍率法及其应用——水杨酸钠、安替比林和咖啡因的同时测定

用吸收比－系数倍率法同时测定撒痛风注射液中水杨酸钠、安替比林和咖啡因三组分的含量。它们的回收率分别为１００．７％～１０２．１％、９５．９３％～１０４．５％和９７．５７％～１０１．７％。