苯酚与甲基叔丁基醚选择性叔丁基化反应的研究

采用甲基叔丁基醚作为叔丁基化试剂,硫酸作为叔丁基化催化剂,研究了苯酚叔丁基化反应,考察了原料配比,反应温度和反应时间对叔丁基化反应的影响。在一定的反应条件下,选择地得到了２,４－二叔丁基苯酚。     

2,6—二硝基甲苯对鲤鱼的毒性

研究测定了２,６－二硝基甲苯（２,６－ＤＮＴ）对鲤鱼的急性和亚致死毒性．亚致死试验经１８０ｍｇ／Ｌ、３６０ｍｇ／Ｌ、５４０ｍｇ／Ｌ、７２０ｍｇ／Ｌ、９９０ｍｇ／Ｌ２,６－ＤＮＴ暴露２１ｄ．在１５℃～１９℃下,２４ｈ、４８ｈ、７２ｈ、９６ｈ的半致死浓度值分别为２５４８ｍｇ／Ｌ、２２９６ｍｇ／Ｌ、２０１２ｍｇ／Ｌ、１９００ｍｇ／Ｌ．亚致死试验中,根据２,６－ＤＮＴ对鲤鱼生长和肝、肾、鳃ＡＴＰａｓｅ活力的影响,求得２,６－ＤＮＴ的最大允许毒物浓度为１８０～３６０ｍｇ／Ｌ．     

福建省旅游气候资源分析

利用福建省气象统计资料,采用旅游气候舒适率指标对全省旅游气候资源进行评价,指出福建旅游气候条件的区域差异,旨在为全面,合理开发利用福建旅游气候资源提供科学依据。     

MnO2和PbO2共沉积电极的阳极行为

探讨了ＭｎＯ２和ＰｂＯ２共沉积电极在硫酸介质中的阳极析氧行为,发现当锰与铅的原子比约为７．１：１。该电极以表面锰原子为析氧活性中心,共沉积的铅对的析氧性能基本无影响。     

核磁共振弛豫时间的测量

本文指出了在核磁共振实验中通常使用的通过测量信号宽度求横向弛豫时间的方法的局限性。介绍了以特殊的射频脉冲序列来测量横向弛豫时间的“自旋──回波”方法和测量纵向弛象时间的“倒置──恢复”方法．     

蒜苔保鲜研究

本文通过对经ＧＡ处理及经ＧＡ和２,４－Ｄ共同处理的离体蒜苔在贮藏过程中水分、可溶性糖、纤维素含量的测定,得出经ＧＡ和２,４—Ｄ共同处理蒜苔保鲜效果较好,因为ＧＡ为可明显防止蒜苔衰老和抑制细胞内含物向珠蒜的转移及再利用;２,４－Ｄ可抑制珠蒜的形成．若同时密封袋装保鲜效果更好．     

Nα-quinaldyl-L-arginine·HCl,a new defensive alkaloid fromSubcoccinella-24-punctata (Coleoptera,Coccinellidae)

The isolation of N-quinaldyl-L-arginine·HCl (1) from the CoccinellidaeSubcoccinella-24-punctata is reported. The structure, first established on the basis of the analysis of the spectral properties of1, has been confirmed by synthesis. The alkaloid is of endogenous origin and markedly deterrent to ants.     

2-Carboxyethylgermanium sesquioxide,a synthetic organogermanium compound,as an inducer of contrasuppressor T cells

2-Carboxyethylgermanium sesquioxide (Ge-132), a synthesized organogermanium compound with immunomodulaing activities, was shown to be an inducer of anti-suppressor T cells in normal mice. The suppressor cell activity of T6S cells, a clone of burn-induced CD8⁺ IL-4-producing suppressor T cells, was clearly inhibited when a mixed lymphocyte-tumor cell reaction of the clone was conducted with splenic mononuclear cells from mice treated orally with a 100 mg/kg dose of Ge-132. The activity of anti-suppressor cells was demonstrated in spleens of mice 2 days after treatment with Ge-132 and reached its peak on day 3. The anti-suppressor cells induced by the compound were of a contrasuppressor T cell-linage, because they were characterized as CD4⁺ CD28⁺ TCR/⁺ Vicia villosa lectin-adherent T cells. These cells produced IFN- but did not produce IL-2, IL-4, IL-6 or IL-10 in their culture fluids. CD4⁺ anti-suppressor T cells induced by Ge-132 may be different from other subsets of CD4⁺ T cells because Th1 and Th2 cells generated in our laboratory did not adhere toVicia villosa lectin-coated petri dishes, and each produced specific cytokines. Th1 cells produced IFN- and IL-2 while Th2 cells produce IL-4 and IL-10 in vitro. These results suggest that Ge-132 may be useful as an inducer of contrasuppressor T cells in immunocompromised individuals bearing suppressor T cells. To eliminate suppressor T cells from immunocompromised hosts may result in improved resistance from various opportunistic infections.     

Surface state of molybdenum cations in MoO3/CeO2

Conclusion  

长江河口海岸演变长周期波动的初步研究

长周期波动作为一种地貌演变现象在河口海岸地区广泛存在,在长江河口,表现为长江河口水下三角洲及长江河口拦门沙地形的波动变化。而在杭州湾北岸,它又以“侵蚀波”的形式来影响岸滩的冲淤演变,本文试图通过揭示人在的动力机制来综合分析春在典型河口海岸演变中的表现。．