丁化作用

It,s allelchemicals were isolated through extraction, thin-layer chromatography, and column chromatograpathy. After the white clover was infused in ethanol and evaporation, the leavings was dissolved by water. The aqueous extract was extracted by petroleum,chloroform, ethyl acetate and n-Butanol successively, and the bioassay showed that the chloroform phase has obvious inhibitory effect, the inhibitory rate was 44.32%,88.08% on Abutilon theophrasti M., seedling length and root length, 82.08%,92.16% on Echinochloa crusgalli L., seedling length and root length, and the Amaranthus retroflexux L., germination rate is 0, the secondly was ethyl acetate phase.

运用萃取、薄层层析、柱层析等方法对白三叶草地上部分的化感物质进行初步分离，结果表明，白三叶草经乙醇浸提旋转蒸发后用蒸馏水溶解，依次用石油醚、氯仿、乙酸乙酯、正丁醇萃取，生物测定表明氯仿组分对杂草的抑制作用最强，对苘麻芽长和根长抑制率分别为44.32%、88.08%，对稗草芽长和根长的抑制率分别为82.08%、92.16%，反枝苋的发芽率为0；其次是乙酸乙酯相。

The results indicate that improving temperature to reflux, using low polarity solvent as dispersion medium and proper molar ratio of tetrabutyl titanate to stearic acid can bring out good modification. The function of tetrabutyl titanate is to react with the surface hydroxyl groups and adsorbed H2O on the powder particles to produce new binding sites such as M—O—Ti—OC4H9and M—O—Ti—OH, which can easily react with the carboxylic acid. As temperature increases from room temperature to reflux temperature, the reactions between RCOO- and Ti change from coordinate bonds to covalent bonds, which makes the carbon chains of stearic acids more strongly bound with the powder particles surface.

研究结果表明，提高处理温度、适当增加复合改性剂中硬脂酸的量并选用极性弱的有机溶剂可达到比较理想的改性效果；钛酸四丁酯的作用是与粉体粒子表面的羟基以及吸附水反应产生偶联点，如M—O—Ti—OH，这些偶联点易于与羧酸反应；在低温时RCOO-与偶联点的Ti之间以配合物的形式发生作用，在回流温度下处理时，主要发生酯化反应，使硬脂酸更牢固地嫁接到粉体粒子表面，改性效果更好。

Chitosan is a product of depolymerization and deacetylation of chitin, which has extensive biofunction because of its complex constructions.

目的：研究几丁糖对成纤维细胞增殖及Ⅲ型前胶原mRNA表达的影响，阐明其抗纤维化的作用机制。

After esterification, the ethyl-2-chloro-3-phenylpropionate reacts with diethyl malonate under the catalysis of sodium ethylate, and we obtain the corresponding triethyl ester. The-benzylsuccinic acid is formed by the triethyl ester reacting with concentrate hydrochloric acid and taking place hydrolyzation and decarboxylation reaction at the same time. In order to avoid the formation of cinnamic acid, the sodium ethylate and diethyl malonate must be react sufficiently. The course has simple operation, inexpensive materials and better yield.

具体制备工艺为：首先以L-苯丙氨酸为原料采用重氮化方法得到-2-氯-3-苯基丙酸，再经酯化得到-2-氯-3-苯基丙酸乙酯后在乙醇钠催化作用下和丙二酸二乙酯缩合，发生SN2反应，得到相应的三乙酯，然后经水解和脱羧，得到-苄基丁二酸；在实验中乙醇钠要和丙二酸二乙酯充分反应，避免生成肉桂酸乙酯；该过程操作简单，原料便宜，产率较高，总收率可达到26.8%。

The following talks including investigation methods, development patterns, interethnic societies and the impact of Han language on the minorities.

人类学本土化与田野调查——元江调查四人谈●胡鸿保周星刘援朝陈丁昆／著田野调查一向是人类学家们看重的研究方法，在中国人类学高度发展的今天，由于人类学本土化的需要，田野调查的作用愈来愈重要。

We demonstrate that both the IL-5 mRNA expression and IL-5 protein production were stimulated by TSA and NaBu treatments. Chromatin immunoprecipitation assays showed that treatments of TSA and NaBu caused hyperacetylation of histones H3 and H4 at the IL-5 gene promoter in Jurkat cells, which consequently promoted the exogenous luciferase activity driven by this promoter.

TSA和丁酸钠能促进IL-5基因的mRNA和蛋白的表达水平，并增强该基因启动子所介导的外源荧光素酶报告基因的活性，这一增强作用与两种抑制剂介导的IL-5基因启动子上组蛋白H3和H4的高乙酰化有关。

OH radicals produced by ultrasound in aqueous solution attack phenolic cycle at adjacent or para position of the hydroxyl on phenol so that phenol is changed into small organic molecules such as muconic acid, maleic acid and ethane diacid. These small organic molecules will be oxidized to form carbon dioxide and water by.

苯酚超声降解的作用机理是，超声空化在水溶液中产生的·OH自由基进攻苯酚苯环上羟基的邻位或对位而使苯环断裂生成己二烯酸、顺式丁烯二酸和乙二酸小分子有机物而使苯酚得以降解，这些小分子有机物在·OH自由基的进一步作用下最终被氧化成CO〓和H〓O。

The famciclovir was synthesized from purine by a series of steps by Acylation, Decarboxylation, Reduction ,and so on; Derivatives of these intermediates is described from the 6-chloro- 9H- purin-2-amine as raw materials in different conditions when the iodine and bromide were synthesized with the addition of two intermediate 6-bromo-9H-purin-2-amine and 6-iodo-9H-purin-2-amine; There is elaborated from the main part of a acetophenone, urineaminohydrochloride, phenylhydrazine, ethyl acetoacetate as raw material through a series of reactions to synthetic 3-phenyl-4-formylphenyl pyrazole and 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-aldehyde two pyrazole aldehyde, and then with 2-amino-6-chlorine-9-(2-methicillin-oxo-co-methyl-4-yl) purine reaction of the two new pyrazole purine Schiff bases.

本论文主是采用以鸟嘌呤为原料，经过一系列的酰基化，脱羧，还原等反应作用下最终得到了产物2-氨基-9-(4-乙酰氧基-3-乙酰氧基甲基丁基)嘌呤；其中的中间体衍生物主要是阐述从以2-氨基-6-氯鸟嘌呤为原料通过在不同的条件下进行溴代与碘代分别合成了另外两种中间体2-氨基-6-溴鸟嘌呤及2-氨基-6-碘鸟嘌呤；还有一部分主要是阐述从以苯乙酮，盐酸氨基脲，苯肼，乙酰乙酸乙酯为原料通过一系列的反应先合成3-苯基-4-醛基吡唑及5-氯-3-甲基-1-苯基-1H-吡唑-4-甲醛这两个吡唑醛，然后再与2-氨基-6-氯-9-(2-甲氧羰基丁酸甲酯-4-基)嘌呤反应得到了两个新型的吡唑嘌呤席夫碱

Besides, n-butyl and sec-butyl tosylate that are difficult for oxidative addition can react with phenylmagnesium bromide to form corresponding cross-coupling products. Primary alkyl halide which contains β-hydrogen and is relatively hard to undergo the reaction , n-butyl chloride for instance, can react with aryl Grignard reagents in the presence of NiB alloy as well.

此外，难以进行氧化加成的对甲苯磺酸正丁酯和对甲苯磺酸仲丁酯可以与苯基溴化镁作用生成相应的交叉偶联产物；反应相对困难的含β-H的伯卤烷，如：正氯丁烷也可以在NiB催化下与芳基格氏试剂发生偶联。

Cellulose acetate butyrate,which is widely applied as coatings additive, is synthesized in the heterogeneous system. The activation is required because of the strong hydrogen intramolecular and intermolecular bondings and the regulation of the crystalline region in cellulose microfibrils.

中文摘要纤维素醋酸丁酸酯（Cellulose acetate butyrate是一种广泛应用于涂料工业的添加剂，由于纤维素具有分子内与分子间强氢键作用以及纤维素纤维的局部规整的结晶序列等特征，一般纤维素在酯化反应前都需要进行预活化处理，工业上纤维素醋酸丁酸酯的合成方法一般都在非均相体系中进行的。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。