交联壳聚糖多孔微球对染料的吸附平衡及吸附动力学分析

研究了交联壳聚糖多孔微球对染料的吸附平衡规律,探讨了染料溶液在不同的初始浓度、pH值及不同吸附剂用量条件下吸附动力学规律及吸附动力学控制机理。结果表明,壳聚糖微球对染料的吸附规律可较好地符合Langmuir吸附等温式,吸附动力学模型可以用表观二级速率方程来描述。     

多支结构的均三嗪衍生物的合成及双光子吸收性质

合成了3个系列各含有单支、双支和三支结构的9个均三嗪衍生物, 测定了它们的线性吸收和发射性质以及双光子吸收和发射性质. 随着三嗪环上侧链数目的增加, 线性吸收谱(吸收峰位于390～440 nm)、荧光谱(发射峰位于460～580 nm)和双光子荧光谱(激发波长800 nm)都发生红移; 各种光谱的强度逐渐增强; 基态与激发态的偶极矩之差Δμ_eg也逐渐增大. 另外, 从单支到三支结构, 双光子吸收截面σ随侧链数目呈非线性增加. 这表明多支结构的双光子吸收存在显著的增强效应.     

均聚物/共聚物共混体系的相行为研究进展

通过控制均聚物与共聚物共混过程中的相行为,能够得到许多性能优异的材料。本文从理论和实验两方面总结了影响均聚物／共聚物共混体系相容性和形态结构的因素,主要包括均聚物的分子量、浓度,共聚物的组成、结构、浓度,与均聚物相应的共聚物组分的分子量,共聚物分子内的相互作用,均聚物与共聚物分子间的相互作用等。     

一维链状二(3-氟苄基)锡二吡啶羧酸配合物的合成、结构及反应机理

一维链状二(3-氟苄基)锡二吡啶羧酸配合物的合成、结构及反应机理;有机锡配合物;吡啶甲酸;合成;晶体结构;生物活性;反应机理     

Primary study on the application of Serum Pharmacology in Chinese traditional medicine

In the paper, two main methods, which are Serum Pharmacology and Traditional Pharmacology, were adopted to study Chinese traditional medicine, such as Ginkgo biloba extract (GBE), ginsenosides (GS) and compound GG (GBE + GS), pharmacology in vitro. The results showed that there were evident difference between the results of Serum Pharmacology and that of Traditional Pharmacology. There was no significant difference between the drug effect of crude GS on nitric oxide (NO) production in ECV304 and that of crude GBE, and the drug effect of GG was superior to that of GS and GBE, respectively. But, compared with GBE serum, the GS serum up-regulation of NO production in ECV304 increased significantly, and the GG serum up-regulation of the NO production in ECV304 was inferior to that of GS serum and GBE serum significantly. The results suggested that Serum Pharmacological study should be adopted in the pharmacological investigation on the Chinese traditional medicine and the drug screening of the Chinese traditional medicine.     

THE N-NITROSAMINES IN TOBACCO SMOKE AND ITS ADSORPTION AND DEGRADATION

N-nitrosamines are strong carcinogens for humans. This paper gives an overview of the nitrosmaines in cigarette smoke including the formation, the harmfulness, the analytical methods of the nitrosmaines and the adsorptions and degradations of N -nitrosamines.     

Laser pretreatment protects cells of broad bean from UV-B radiation damage

In order to determine the role of lasers in the stress resistance of broad bean (Vicia faba L.) to ultraviolet-B (UV-B) radiation, the embryos in seeds were exposed to He-Ne laser or CO2 laser radiation. Afterwards they were cultivated in Petri dishes in a constant temperature incubator until the lengths of epicotyls were nearly 3 cm. The epicotyls were then exposed to 1.02, 3.03 or 4.52 kJ m(-2) UV-B radiation, respectively, under 70 micromol m(-2) s(-1) photosynthetically active radiation (PAR) in a growth cabinet. Changes in the concentration of malondialdehyde (MDA), ascorbic acid (AsA) and UV-B absorbing compounds (absorbance at 300 nm) were measured to test the effects of laser pretreatment. The results showed that laser pretreatment of embryos enhanced UV-B stress resistance in the epicotyls of the broad bean by decreasing the MDA concentration and increasing the content of AsA and UV-B absorbing compounds. We suggest that those changes in MDA, AsA and UV-B absorbing compounds were responsible for the increase in stress resistance observed in the broad bean. This is the first investigation reporting the use of laser pretreatment to protect the cells of the broad bean from UV-B-induced damage.     

贵金属Au冷却过程中结构及能量变化的分子动力学计算机模拟

通过分子动力学方法,研究了不同冷速下贵金属Au在温度2000～300K的冷却过程中微观结构的变化特点。结果发现,冷却速度对Au的微观结构产生重要影响。采用偶关联函数和键对分析技术对原子局域团簇结构进行分析,并考察了冷却过程中原子势能随温度的变化,比较了Au的微观结构转变与能量变化的对应关系,从能量转化的角度对冷却过程中Au的结构变化进行了说明。     

超疏水多孔阵列碳纳米管薄膜

碳纳米管由于具有特异的力学[1] 、光学[2 ] 、电学[3,4 ] 和磁学性质[5] ,使其在锂离子电池[6 ] 和平板展示器[7] 等方面呈现出广泛的应用前景 .Ebbesen等[8] 对无序碳纳米管材料的浸润性进行了详细研究 ,发现其很容易被水润湿 .然而 ,阵列碳纳米管膜的浸润性研究尚未见报道 .固体表面的浸润性主要由表面化学组分和几何结构两方面控制 .通常 ,加大表面粗糙度可以增强其浸润性 [9～ 16 ] .近来 ,超疏水表面 (即与水的接触角大于 1 5 0°的表面 )的研究显示了广泛的应用背景[13～ 16 ] .这种表面通常可由增加表面粗糙度和降低表面能来制备[1…     

热处理对高硫化氢合成气一步法制甲硫醇K2MoO4-NiO/SiO2催化剂结构及性能的影响

 在不同焙烧温度和焙烧气氛下对共浸渍法制备的 K2MoO4-NiO/SiO2 催化剂进行热处理, 并采用 X 射线衍射、热重-差示扫描量热、氢气程序升温还原、拉曼光谱和电子自旋共振波谱等手段对催化剂进行了表征, 同时考察了催化剂催化高硫化氢合成气一步法制甲硫醇的性能. 结果表明, 由于催化剂中所含柠檬酸氧化放热, 空气中焙烧的催化剂发生严重烧结. 随着焙烧温度的升高, 八面体配位的 Mo(Oh) 逐渐向四面体配位的 Mo(Td) 转变, 导致催化剂的还原能力降低, 配位不饱和 Mo (CO 吸附位) 减少, 因而 CO 转化率降低. 甲硫醇的生成与 Mo–S–K 相密切相关, 而 MoS2 晶相表面主要生成烃类. 与氮气中焙烧的催化剂相比, 空气中焙烧的催化剂表面的 MoS2 相较多, 而 Mo–S–K 相较少, 因此具有更高的烃类选择性和更低的甲硫醇选择性.