野生和人工养殖暗纹东方鲀不同组织中河豚毒素(TTX)含量的初步研究

采用小鼠生物检测法测定了野生和人工养殖暗纹东方不同组织中河豚毒素（ＴＴＸ）的含量．野生暗纹东方不同组织中ＴＴＸ含量由高到低依次是：卵巢、肝脏、胃肠、肾脏,肌肉毒性最小;而人工养殖暗纹东方不同组织中ＴＴＸ含量都极低,几乎无毒．结果表明,用人工养殖方法可以培育出低毒或无毒河豚,在一定程度上支持了河豚毒素的微生物起源学说．     

小菜蛾Plutella xylostella羧酸酯酶、酰胺酶及乙酰胆碱酯酶的研究

研究结果表明,小菜蛾(Plutella xylostella)乙酰胆碱酶、酰胺酶的最适pH值分别为8.0和8.5。pH值对闳酸酯酶活力影响较小,酰胺酶和羧酸酯酶反应速度在反应开始60钟内,仍在线性范围,乙酰胆碱酯酶反应速度在反应开始的8分钟内呈线性关系。羧酸酯酶、酰胺酶和乙酰胆碱酯酶的Vmax分别为551.81(nmol/mg,mln)、5.25×10~(-4)(μmol/mg.min)和20.36(nmol/mg.min);km分别为5.52×10~(-5)(mol)、1.18×10~(-3)(mol)和8.33×10~(-3)(mol)。     

体上矩阵方程AXB=C的（反）次自共轭解

设Ｆ是一个具有对合反自同构的体,定义了Ｆ上的（反）次自共轭矩阵,给出了Ｆ上的矩阵方程ＡＸＢ＝Ｃ有（反）次自共轭解的充要条件及其解的表达式。     

Electrophysiological research of synapse formation from beginning to maturity

The development of synapses is an important question in neurobiology. We employ patchclamp technique to record MEPCs and EPCs of myoballs inXenopus cell culture. The rate of EPC/MEPC is related with synapses maturation. Accordingly, we define the mature synapses as those whose rate of presynaptic membrane ’ s EPC to MEPC is more than 8. The process of maturation needs about 2–5 h after neuntes contact with myoballs. We divide the development of synapses into three stages: young, developing and mature. The neurotransmitters stack gradually and increase by hundreds of times along with young synapses growing into maturity. So the process of synapses maturation should include presynaptic membrane specialization, postsynaptic membrane specialization and neurotransmitters stack.     

Schiff碱型双(苯并-15-冠-5)对碱金属苦味酸盐的萃取性能研究

用五种Ｓｃｈｉｆ碱型双（苯并＿１５＿冠＿５）为离子载体,在水＿１,２＿二氯乙烷体系中研究了其对碱金属苦味酸盐的萃取性能,测定了分配比Ｄ和萃取平衡常数Ｋｅ．结果表明,这些双冠醚与苦味酸钠以１∶１（冠醚单元∶金属离子）形式络合,而与苦味酸钾和苦味酸铷则以２∶１形式络合．     

High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method

Two national stalagmite standard (GBW04412, GBW04413) and one international coral standard (RKM_4) have been determined by using thermal ionization mass spectrometry (TIMS) method. The values of ( 234 U/ 238 U) act , ( 230 Th/ 234 U) act and age are all consistent in error range with the standard values obtained by using α spectrometry.     

Structural and expressional analysis of a cDNA that expresses predominantly in rice stamens

The development of stamen is an important stage during the sexual reproduction in higher plants. Studying the genes that predominantly or even specifically expressed in stamens will aid in undestanding the molecular mechanism of stamen development. The structure of a rice CHS-like gene (D5) which predominantly expressed in anthers has been analysised, showing high structural similarity with two other anther-specific genes (A1 and BA42) fromBrassica napus. Northern analysis also reveals that the three genes share a similar expression pattern and that the expression of D5 may relate to the early development of pollens. It is concluded that D5, A1 and BA42 represent a group of diverged CHS-like genes which are related to stamen development.     

New evidence for the Qinghai-Xizang (Tibet) Plateau as a pilot region of climatic fluctuation in China

Over 40 a observed temperature data in 172 stations in China and historical proxy data were analyzed. Evidence suggested that during 1980–1994, the warmest year appeared first in southeastern part of the Qinghai-Xizang (Tibet) Plateau (henceforth SETP) and then gradually spread northwards and eastwards to eastern China. The climatic change on century time scale in recent 600 a shows 3 relatively warm and clod stages in China. Each warm and cold stage appeared first in Tibet Plateau (henceforth TP) and then in the Qilian Mountains, then in the eastern parts of China. The warm and cold stages in TP were 10–60 a earlier than in the eastern China. The facts show that TP is a pilot region of climatic fluctuation in China on the time scale shorter than 10³a.     

Preparation and optical properties of solid solution semiconductor (Zn x Cd1−x S) doped silica glasses

Semiconductor(Zn_xCd_1−x S) doped silica glasses were prepared by Sol-Gel process andin situ growth technique. The structure of the materials was characterized by X-ray diffraction technique, the particle size of semiconductor crystallites from X-ray patterns was estimated less than 10 nm. From absorption spectra, it is obtained that the absorption edges shifted to short wavelength direction when Zn contents increased, and the absorption edge can be adjusted from 2.46 eV to 2.96 eV by controlling Zn contents. The third-order nonlinear optical susceptibility was studied at 532 nm with 8 ns pulse laser by degenerate four wave mixing (DFWM) technique.     

Comprehensive evaluation of mechanism of “chimney effect” using principles of magnetism, geochemistry and mineralogy

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.