叔丁醇-水混合溶剂的混合状态对牛血清白蛋白构象的影响

应用动态光散射法测定了叔丁醇(TBA)-水混合溶剂中牛血清白蛋白(BSA)流体动力学半径, 并通过分析BSA的荧光光谱和紫外-可见光吸收光谱, 研究BSA在TBA-水混合溶剂中的构象变化. 同时, 通过分析TBA-水二元体系和BSA-TBA-水三元体系静态散射光的变化, 探讨TBA-水溶剂体系的混合状态及其对BSA在水溶液中构象变化的影响. 结果表明, TBA-水溶剂体系的混合状态与BSA的构象变化密切相关, 低浓度的混合溶剂中, 水分子在TBA周围形成疏水水化结构, 与蛋白质疏水基团的选择性结合, 破坏了蛋白质的稳定结构, 但是, 少量TBA的加入削弱了蛋白质疏水基团间的疏水相互作用, 有利于蛋白质形成更紧密的构象; 高浓度的混合溶剂中, TBA分子相互聚集形成胶束, 削弱了对蛋白质的变性作用.     

水合烟酸铜Cu(Nic)2•H2O(s)(Nic＝烟酸)的合成、表征及热力学性质

近几十年来,烟酸盐类化合物或配合物由于优越的吸收率高和无毒副作用等特点使其在化妆品、药品和食品等领域作为营养添加剂具有重要应用前景。然而,这类化合物的基础热力学数据极其缺乏,从而限制了这类化合物的理论研究和应用开发的深入开展。为此,本论文利用室温固相合成方法和球磨技术合成了一种新化合物Cu(Nic)2•H2O(s),利用化学分析、元素分析、FTIR和X-射线粉末衍射技术表征了它的结构和组成,利用精密自动绝热热量计准确地测量了它在78-400 K温区的摩尔热容。在热容曲线的T ＝ 326-346 K温区观察到一个明显的固-液相变过程。利用相变温区三次重复实验热容的测量结果确定了此相变过程的峰温、相变焓和相变熵分别为：Tfus＝(341.290 ±0.873) K, DfusHm＝(13.582±0.012) kJ×mol-1, DfusSm＝(39.797±0.067) J×K-1×mol-1。通过最小二乘法将相变前和相变后的热容实验值分别拟合成了热容对温度的两个多项式方程。通过热容多项式方程的数值积分,得到了这个化合物的舒平热容值和相对于298.15 K的各种热力学函数值,并且将每隔5 K的热力学函数值列成了表格。     

端位炔酮与有机锌试剂的自缩合反应

端位炔酮与有机锌试剂CF3CO2ZnEt作用发生自缩合反应,得到较高产率的β取代的Morita-Bayllis-Hillman产物,提供了三取代烯烃化合物的合成方法;而与有机锌试剂CF3CO2ZnCH2I作用时,烷基炔酮不发生反应,只有活性较高的芳基炔酮才能进行反应,得到中等产率的2,5-二氢呋喃衍生物。     

New 3-（4-arylpiperazin-1-yl）-1-（benzo[b]thiophen-3-yl）-2-methylpropanol derivatives：Synthesis and evaluation for dual 5-HT1A/SSRI activities

A series of 3-（4-arylpiperazin-1-yl）-1-（benzo[b]thiophen-3-yl）-2-methylpropanol derivatives were designed and synthesized based on 5-HT1A/SSRI drugs design strategies.The synthesized compounds were evaluated for their dual 5-HT1A/5-HTT activities.     

Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives （14a-1） were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers, and their cytotoxicity against HepG2 cells in vitro were evaluated by MTT method. It was found that 14c, 14d, 14f, 14i, 14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil. NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 × 10^-2 μmol/L, whereas 14a and 14h with very weak activity only released NO of 1 × 10^-2 μmol/L.     

A new phenolic compound from Crinum asiaticum L.

A new phenolic compound was isolated from the ethanol extract of the bulbs of Crinum asiaticum L.var.sinicum Baker.Its structure was defined as 1-（2-hydroxy-4-hydroxymethyl）phenyl-6-O-caffeoyl-β-D-gluco-pyranoside on the basis of spectroscopic evidences.     

D301 resin as a solid base for phosphine-free Heck reactions with heteroaryl halides

A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality（Grade Matrix Structure：Styrene-DVB D301R）,used as base to Heck reactions catalyzed by palladium reagent without phosphine compound as ligand is described.It was found that the D301 resin used as base is an efficient and reusable base and can be regenerated and recycled in the reaction.The olefmation of heteroaryl halides prepared the corresponding products in good yields using D301 resin as base.     

合成指标评价的RBF神经网络法研究

合成指标往往没有真值,使其无法通过RBF神经网络法进行学习以获得分项指标在确定合成指标时的具体结构,导致该法不能对指标体系合成指标进行拟合与评价,从而限制了神经网络法在该领域的应用.如果合成指标具备整体递增的属性,则在不失人们对合成指标习惯性要求的前提下,可以通过最小二乘映射法获得合成指标的虚拟真值,以...     

基于双通道探针式81°倾斜光纤光栅的甲胎蛋白免疫检测

提出了一种双通道探针式81°倾斜光纤光栅(81°TFG)传感器,并将其用于甲胎蛋白(AFP)的免疫检测研究.首先,在81°TFG端面镀银膜形成反射式81°TFG,构建由2×2耦合器和两支81°TFG探针组成的双通道传感器.然后,在栅区表面修饰大尺寸AuNs粒子和GO,并以AFP单克隆抗体为特异性识别单元修饰栅区表面,实...     

影响DAS精度的几种因素

在基于数据采集的DAS中,从设计角度出发,详细地分析了系统的传感器,预处理电路,噪声,采样频率和干扰系统精度的影响。