溶剂离解

Because of the low pH and dissociality of hydrofluoric acid, people often ignore the severity of symptoms after contact it. However, the hydrogen ion and free fluoride ion exist persistently.

摘要氢氟酸是目前工业界常见的强酸性溶剂，但是因为在强酸类中是属於较低酸性及低解离度，故对身体立即性之损伤较少，延迟产生之损伤合并症较多，因此异常接触后易使人轻忽其伤害之严重性。

The invention uses the fermentation liquor of one Escherichia coli generating polysialic acid as material, filters and removes thallus, adds some solvents as sodium chloride and alcohol into supernatant to deposit polysialic acid, dissolves the polysialic acid deposits via deionized water, filters to remove modified protein, uses alkali prolease to treat filtrate, complexes deposits via cetyl pyridinium chloride or cetyltrimethylammonium bromide, and dissociates, uses over alcohol to deposit polysialic acid, dissolves the deposits via ultra-pure water, grades and purifies via chromatography column, collects and dialyzes eluent, cools and dries to obtain polysialic acid.

本发明以一株产聚唾液酸大肠杆菌的发酵液为原料，经过过滤去除菌体，上清液加入适量氯化钠和乙醇等溶剂沉淀出聚唾液酸，聚唾液酸沉淀用去离子水溶解，再用过滤去除变性蛋白质，滤液经过碱性蛋白酶处理、氯代十六烷基吡啶或十六烷基三甲基溴化铵络合沉淀并解离后，再用过量乙醇沉淀出聚唾液酸，聚唾液酸沉淀用超纯水溶解，用层析柱进行分级纯化，收集洗脱液经过透析，冷冻干燥得聚唾液酸产品。

Eleven α-V-group cation-substituted toluenes (1) and acetophenones (2)were synthesized. The equilibrium acidities of these compounds were determined indimethyl sulfoxide solution by the "Overlapping Indicator Method" and the homolytic C-Hbond dissociation energies were derived from a thermodynamic cycle combining pKawith oxidation potential of carbanion.

合成了α-位有第V、Ⅵ主族元素杂正离子取代基的甲苯系列（1）和苯乙酮系列（2）共11个Ylide前体化合物，用重迭指示剂法首次测定了其在二甲亚矾溶剂中的酸性解离常数PKa，同时结合碳负离子氧化电位的测定，通过热力学循环估测了它们的气相均裂键能。

A new method for the separation and purification of chiral mandelic acid by heated benzene extraction and refrigeration crystal was established. The ionization constant of mandelic acid was mensurated by pH potentiometer titration.

采用pH值电位滴定法测定了扁桃酸的离解常数，采用高效液相色谱法考察了扁桃酸在不同溶剂中的溶解度曲线和在苯-水体系中于不同pH值条件时的分配率，建立了热苯萃取和冷却结晶的扁桃酸纯化工艺。

The solubility curve of mandelic acid in different solvent and the distribute ratio of mandelic acid in benzene-water system in different pH condition were determine by HPLC. The results showed that the ionization constant pK_a of mandelic acid was 5.28, the solubility of mandeli...

研究结果显示，扁桃酸的离解常数pKa值为5.28；扁桃酸在水和苯中的溶解度曲线可分别表示为：S=38.756e0.0354t和S=0.2746e0.0649t；扁桃酸在水和苯中的溶解度差值曲线可分别表示为：ΔS/S1=0.1196t-2.712和ΔS/S1=0.3688e0.0723t；苯是最适合用于冷却结晶的溶剂；热苯萃取扁桃酸的苯水比例可选为1∶1；降低pH值有利于扁桃酸在苯中的分配。

Topics discussed include ultrafast spectroscopic techniques; aspects of electron transfer reactions ranging from solvent effects; intermolecular and intramolecular systems, to dynamics at semiconductor surfaces; the dynamics of chemical systems using Raman spectroscopy; pericyclic photochemical rearrangements and photodissociation reactions; solvent--solute interaction dynamics; and chemical dynamics in clusters.

讨论的议题包括超快光谱技术，电子转移反应的溶剂效应等方面；分子间和分子系统，动力在半导体表面，使用的化学拉曼光谱系统动力学；周环重排和光化学解离反应；溶剂-溶质相互作用的动态以及在化学动力学组。

We found, on the one hand, urea can cause cytochrome cboth on the electrode surface and in the solution to be denatured and then the denaturedprotein lends to move the formal potential of the native protein in the bulk solution to amore negative value; and on the other hand, urea can also cause the formal potential ofnative protein in the bulk solution to shift positively with decreasing the degrees ofdissociation of electrolytes and polarity of the urea-water solvent.

我们发现脲能引起电极表面和溶液中的细胞色素C的变性，变性蛋白质能导致本体溶液中天然蛋白质的标准式电位的负移；另一方面，通过降低电解质的离解度和脲-水溶剂的极性，脲能使本体溶液中天然蛋白质的标准式电位正移。

Kinetics on the reaction of epoxy resin with acrylic acid has been studied.

本工作研究了以丙烯酸和环氧树脂为原料合成丙烯酸环氧酯的动力学，认为该反应是一级反应，在此基础上提出了反应机理同时研究了不饱和酸离解常数及溶剂对反应速率常数的影响，进一步支持了上述观点；并且求出了在不同温度中的反应速率常数及反应的活化能。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了