溶剂

Tetrachloroterephthalic acid was prepared by chlorinating terephthalic acid, oleumsolvent and iodine catalyst. Tetrachloroterephthalic acid was acylated by sulphurous oxychloride in the presence of DMF to form tetrachloroterephthaloyl chloride. The acyl chloride product was fluorinated by potassium fluoride and esterified by methanol to synthesize dimethyl tetrafluoroterephthalate. The ester was reduced with potassium borohydride and lithium chloride to give tetrafluoroterephthalyl alcohol. The above product was bromated in the hydrobromic acid to obtain 4-bromomethyl-2,3,5,6-tetrafluoro-benzene methanol. 4-Methyl-2,3,5,-6-tetrafluorobenzene ethanol was obtained by reducing the bromide with magnesium. In the exist of DCC and DMAP, tefluthrin was got by the condensation reaction between 4-methyl-2,3,5,6-tetrafluoro-benzene methanol and-(1RS,3RS)- 3-(2- chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethyl cycolpropanecar-boxylate acid.

对苯二甲酸与氯气在碘存在下以发烟硫酸为溶剂进行氯化制备四氯对苯二甲酸；再以DMF为催化剂与二氯亚砜反应生成四氯对苯二甲酰氯；以氟化钾为氟化剂，环丁砜为溶剂置换氟化，再与甲醇酯化得到四氟对苯二甲酸甲酯；以KBH4-LiCl为还原剂二甲醚为溶剂反应制得四氟对苯二甲基苄醇；以氯苯为溶剂在溴化氢溶液中溴化得到溴化产物；在乙醇溶液中经镁粉还原得到4-甲基-2，3，5，6-四氟苄醇；甲基苄醇与功夫酸在催化剂二环己基碳二亚胺和4-二甲氨基吡啶作用下缩合得到七氟菊酯，总收率达43.6%。

From the photophysical behaviors of 1, 3, 4-triaryl-2pyrazoline compound (TPP16) at low temperature, it can be considered that the twisted configuration between pyrazoline ring and the non-substituted phenyl group on the position 1 is the fluorescence configuration of conjugated system Ⅰ, and the twisted configuration between pyrazoline ring and P-nitrobenzene group is fluorescence configuration of conjugated system Ⅱ.

研究了1，3，4-三芳基-2-吡唑啉化合物TPP16在低温时的发光情况，发现：在低温77K下，共轭体系Ⅰ(苯基-N1-N2＝C3-苯基)在非极性溶剂中不发荧光，在极性溶剂中有较强荧光发射；而共轭体系Ⅱ(N1-N2＝C3-C4＝对硝基苄叉)在非极性溶剂或极性溶剂中均有荧光发射，表明N1所联取代基与吡唑啉环相扭曲的构象是共轭体系Ⅰ的发光构象，而对硝基苄叉与吡唑啉环相扭曲的构象是共轭体系Ⅱ的发光构象。

The present invention provides a method for preparing biodegradable and biocompatible, porous, polymeric scaffolds for tissue engineering, which comprises the steps of: dissolving a polymer in an organic solvent to prepare a polymeric solution; mixing an effervescent salt in the resulting polymeric solution to give a polymer/salt/organic solvent mixed gel; removing the organic solvent from the polymer/ salt/ organi c solvent mixed gel; and effervescing the salt in the resulting polymer/salt gel to yield a polymeric scaffold.

一种用于组织工程学的生物可降解和生物相容的多孔聚合物支架的制备方法，该方法包括下列步骤：在一种有机溶剂中溶解一种聚合物以制备聚合物溶液；在所得的聚合物溶液中混入泡腾盐，得到聚合物／盐／有机溶剂混合的凝胶；从聚合物／盐／有机溶剂混合的凝胶中除去有机溶剂；和在酸性溶液中浸泡所述凝胶以使所述盐泡腾产生聚合物支架。

Draw and add the solvent only to once, recycle in a set of sealed equipment, the solvent in the dregs of a decoction can be retrieved out basically, so solvent consumption than many of draw pot to be 30% more than less only, the consume can reduce 50-70%, it is better for draw with the organic solvent, active principle in the sublimating of the traditional Chinese medicine.

提取只加1次溶剂，在一套密封设备内循环使用，药渣里的溶剂基本上能回收出来，故溶剂用量比多只提取罐少30%以上，消耗率可降低50～70%，这为用有机溶剂提取，提纯中药中有效成份铺平了道路。

DM is mainly used as high-boiling point solvent for printing ink, dyestuff, resin, cellulose and painting.

二乙二醇丁醚醋酸酯有着十分高的沸点，主要用于高温烤瓷以及印刷油墨的高沸点溶剂，也用作乳胶漆的助聚结剂；由于该溶剂挥发速度很慢，在水中溶解度低，所以可作为丝网印刷油墨的溶剂，以及聚苯乙烯涂料印花釉的溶剂；也可作为共沸剂用于醇与酮的分离。

Co., use solvent Zai, if you have a small number of high-boiling solvent, can also cause residual solvents are too high, or even to cause business card printing and membership card making products has serious peculiar smell

查抄用于油不朱的溶剂和制卡和会员卡制作所搁置的溶剂是否纯真，如果有多度的矮沸不面溶剂，也不定变不败溶剂残留度过矮，甚至导致制卡和会员卡制作品活命惨重的异味

The results suggested that chitinhad a good solubility in the new solvent when its at -30℃and below, but the solubilityof chitin no longer increasesd notable as the temperature reduced; The joined of urea, incertain degree, strengthened the solvency of alkali solvent to chitin. When theconcentration of sodium hydroxide is 8%～12%, Chitin had a good solubility, and theapparent viscosity of chitin solution could up to 4000 mpa·s～5000mpa·s at roomtemperature; In addition,the solubility of chitin in new solvent was high when therefrigerated time was three days and above, but the refrigerated time could not too long,otherwise, the deacetylize degree of chitin got more bigger. The properties of chitin solution were tested by revolving viscosimeter, FT-IR,X-RD and so on.

结果表明，在-30℃及以下甲壳素能很好的溶解于新溶剂中，但甲壳素的溶解度不再随温度的下降而有所增大，而是基本保持不变；尿素的加入，在一定程度上强化了强碱溶剂对甲壳素的溶解，当新溶剂中NaOH浓度为8％～12％时，甲壳素在试验温度下可以获得较好的溶解度，所得溶液在室温下的表观黏度达4000 mpa·s～5000mp·s；冷冻时间为3 d及以上时，有利于甲壳素的溶解，超过3 d，甲壳素的溶解度变化不大，另外，冷冻条件下，甲壳素在强碱溶剂中仍会发生脱乙酰化反应，冷冻时间不宜太长。

It is shown that in solution the ion pairs can exist in such different forms as contact ion pair, solvent-separated ion pair or free solvated ions. Solvent polarity influences not only the spectral properties of different forms, but the equilibrium between them as well, leading to change of physicochemical properties of the ion pairs.

观察到在溶剂中离子对可以各种形式存在，如紧密离子对、溶剂分隔离子对或溶剂化的自由离子，溶剂的极性不仅影响各种存在形式的光谱性质，而且影响它们之间的平衡关系，进而影响离子对体系的物理化学性质。

Upside-down taper extracting tank is very beneficial to the circulative extraction from downwards to upward, through the water dividing board and sieve specially designed at the tank bottom, the extracted solvent can make upward movement evenly from the tank bottom. As the tank volume gradually decreases from the tank bottom to the tank top, the short circuit during the flow of solvent can be avoided. Upside-down taper extracting tank is the ideal upgraded equipment for the technology requiring the realization of dynamic extraction processing.

倒锥型提取罐对溶剂的循环提取极为有利，当提取溶剂从上到下循环提取时，通过罐底专门设计的分水板和筛网，提取溶剂能够均匀地从罐底部向上运动，而且由于从罐底部向灌顶部逐渐缩小，所以能很好的避免溶剂流动时短路现象，对于需要实现动态提取加工的工艺而言，倒锥型提取罐是极为理想的升级换代设备。

And we established six new synthetic routes to nanostructured materials, such as (1) solvothermal element direct reaction,(2) organic solvent room-temperature conversion,(3) solvothermal co-reduction,(4) solvothermal self-reduction,(5) mid-temperature reduction-Pyrolysis-Catalysis,(6) hydrothermal chemical self-regulation, etc. Successfully synthesized over twenty kinds of semiconductor, InAs, InSb, diamond, CdS, ZnSe, CdSe, CdTe, HgSe, HgTe, ZnGa〓O〓 and so on.

建立了溶剂热元素直接反应、有机溶剂室温转化、溶剂热共还原、溶剂热自还原、中温热解催化合成、水热化学反应自控制等六种纳米材料合成新方法，成功地合成出InAs、InSb、金刚石、CdS、ZnSe、CdSe、CdTe、HgSe、HgTe、ZnGa〓O〓等二十余种半导体纳米材料。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。