1,6—二磷酸果糖制备研究：Ⅰ.菌种的筛选及培养条件

介绍了１,６－二磷酸果糖产生菌的筛选和最佳培养条件的确定,在所筛选的菌种中９５１８、９５１９号菌株均具较高的产１,６－二磷酸果糖酶系活力。其最佳培养条件为：培养温度２８℃,ｐＨ６．５。     

V棱镜法测掺Yb^3＋激光玻璃折射率

用Ｖ棱镜法测量了一类非常用应用前景的掺Ｙｂ＾３＋激光玻璃的折射率,得到了一些有用的数据,对有关掺Ｙｂ＾３＋激光玻璃的研究工作起了一定的辅助作用。     

Leakage of mantle helium from the Liaodong Peninsula, China

The isotopic cumpositions of helium have been investigated in hot spring gases sampled from the Liaodong Peninsula. China. The³He/⁴He ratios range from 0.14 Ra (0.14 times the atmospheric³He/⁴He ratio of 1.40 × 10^-6 to 0.72 Ra.³He/⁴He versus⁴He/²⁰Ne ratios and He contents suggest that a small amount of mantle-derived helium reaches the earth’s surface. Helium iwtope ratios of the hot spring gases show a distribution pattern similar to the regional heat flow values, indicating that the positive thermal anomaly occurring in the rtrea is closely associated with the presence of mantle-derived helium. The observations described above provide some significant evidence that the molten magma originating from partial melting of the upper mantle may have intruded into the continental crust along the activity fault. The coupling of the presence of mantle He and heat flow anomalies to seismic activity in studied region seem to imply that there is an internal relationship between mantle degassing and seismic activity.     

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.     

Signal transduction pathways mediated by colony stimulating factor-1 receptor

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     

Two tyrosines in CD3ε-ITAM are required to induce T lymphocyte apoptosis

CD3ε of T cell antigen receptor complex (TCR/CD3) plays an important role in the resembling of the complex and activation signaling through its conservative immunoreceptor tyrosine-based activation motif (ITAM) in the cytoplasmic tail. Previous study showed that a chimera molecule, consisting of the extracellular-transmembrane domain of human CD8α fused to the cytoplasmic domain of CD3ε, induced apoptosis of T lymphocytes, indicating that apoptotic signals were transduced through the CD3ε- ITAM. To elineate involvement of the two tyrosines in apoptotic signaling pathway, cDNAs with mutations at Y170F, Y181F and Y170F/Y181F in CD8-ε-ITAM were made by point mutation and PCR, and then cloned into pcDNA3 eukaryotic expression vectors. Stable expression cell lines were established after transfection of the expression vectors into CD8+- Jurkat T lymphocytes. Stimulation of these cell lines with anti-CD8 monoclonal antibody showed that only the cells with expression of wild type chimera CD8-ε died by apoptosis, but not those cells with expressions of mutated CD8-ε chimera, indicating that the two tyrosines in CD3ε-ITAM were required for the apoptotic signal transduction in T lymphocytes.     

TS分子筛的催化氧化性能研究：Ⅲ.苯酚氧化制苯二酚

研究了自合成的钛硅分子筛（ＴＳ－１）对Ｈ２Ｏ２氧化苯酚制苯二酚反应的催化活性。对反应的温度、时间、催化剂用量、酚：Ｈ２Ｏ２等因素进行了考察：在催化剂用量为苯酚的１０％、酚：Ｈ２Ｏ２（ｍｏｌ）为３：１时,经５７℃／６ｈ反应,Ｈ２Ｏ２的转化率和对产物苯二酚的利用率可达９０％和８０％,还观察到,分子筛的晶粒大小对苯酚的氧化活性影响较大,大晶粒催化剂的内表面利用率较低,从而影响催化活性。     

KCaF3结构相变的分子动力学模拟

基于无调节参数的Ｇｏｒｄｏｎ－Ｋｉｍ势和一种检测离子运动的新技术,以ＫＣａＦ３的分子动力学模拟结果为例,对钙钛矿ＡＢＸ３的离子分子固体的结构相变作了探讨．包括对阱势、折叠结构、能垒、超离子态、稳定性骨架和离子分子集团ＢＸ６的“尺寸”和“形状”．以期对离子分子固体的结构相变有一个基本了解．     

1,3—二氯—2—丙醇氧化反应的研究

对１,３－二氯－２－丙醇的氧化反应进行了系统的研究,将８４％的硫酸溶液慢慢滴加到包含有１,３－二氯－２丙醇和重铬酸钠水溶液的反应容器中去,将体系保持在２４℃～２６℃拦反应６ｈ,反应完成后,过滤回收１,３－二氯丙酮粗品,粗品用冰水洗涤,然后通过蒸馏经可获得８０．４％的收率的１,３－二氯丙酮,这是一种合成１,３－二氯丙酮较好的工艺,这种工艺与同类文献介绍的方法比较目标产物收率提高１０％,而反应时间缩短     

The Relation between the Sensitivity and HeatingVoltage of ZnSnO 3 Gas Sensor

对ＺｎＳｎＯ３气敏元件特性的测试结果表明,元件灵敏度随加热电压的变化而变化．当加热电压小于某一特定值ＶＨ０时,灵敏度不变;当加热电压大于３倍ＶＨ０时,灵敏度降低,元件失效。通过Ｘ射线衍射和ＳＥＭ二次电子能谱等检测实验,找出了气敏元件灵敏度降低的原因．