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METHOD: Reduction reaction, condensation reaction and cyclization reaction were studied by microwave irradiation.

对硝基还原反应、缩合反应、环合反应采用微波催化的方法进行。

These dendritic NOBIN derived Schiff base ligands have been applied to titanium catalyzed hetero-Diels-Alder reaction of Danishefshy's diene and aldehydes, affording the corresponding 2-substituted 2, 3-dihydro-4H-pyran-4-one in quantitative yields and excellent enantioselectivities (up to 97. 2%ee). Comparing the reactivities and enantioselectivities of reaction catalyzed by the titanium complexes of these Schiff base ligands, it was found that a series of ligands L〓 were superior to the other three series of ligands L〓, L〓 and L〓, a significant positive NLE and a dendrimer effect existed in the L〓 dendritic catalyst system. The disposition of the dendritic wedges and the dendron size in the ligands were observed to have a significant impact on the enantioselectivity of the reaction.

NOBIN衍生的树枝状大分子希夫碱手性配体与钛形成的配合物在催化不对称杂Diels-Alder反应中的应用将得到的四个系列NOBIN衍生的树枝状希夫碱三齿手性配体与四异丙氧基钛形成的配合物用于催化Danishefsky's diene与醛的不对称杂Diels-Alder反应，通过反应条件的优化，获得了定量的收率和最高达97.2％ee值的对映选择性；考察了这四个系列NOBIN衍生的树枝状希夫碱钛配合物的催化活性和对映选择性，结果发现它们的活性次序依次为L〓≈L〓＞L〓＞L〓，对映选择性次序依次为L〓＞L〓＞L〓＞L〓。

The factors that affected the content of dialdehyde in dialdehyde starch included reaction time, reaction temperature, concentrations of sodium periodate, reaction pH, and the ratio of sodium periodate to starch.

影响双醛淀粉的双醛含量的因素有反应时间、反应温度、高碘酸钠浓度、反应pH值及高碘酸钠与淀粉的摩尔比。

This specific preparation methods including: parathion of the initial reaction in acid and zinc metal in the common under redox reaction, a product of the reduction of parathion - parathion, with the sodium nitrite in the cold under diazotization reaction, and bovine serum protein tyrosine on the o-hydroxy combination of the adult immune original and immune rabbit polyclonal antibody preparation.

本发明制备方法具体包括：以对硫磷为反应初始物，在酸和金属锌的共同参与下进行氧化还原反应，得对硫磷还原产物对氨基对硫磷，再与亚硝酸钠在低温下进行重氮化反应后，与牛血清蛋白酪氨酸上羟基的邻位结合，制备成人工免疫原，并免疫新西兰大白兔制备多克隆抗体。

In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.

本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应，由于溴代苯乙酮是含有羰基的卤代烃结构，它可以发生亲电取代和亲核加成反应，当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时，控制反应条件可以发生单取代和双取代两种产物；当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时，溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物，这在以前的研究中是没有发现的。

The nucleic acid in the virion was determined to be single-strande d RNA by means of diphenylamine reaction,orcinol reaction and formaldehyde reaction.

病毒核酸地衣酚反应呈阳性，联苯胺反应呈阴性结果。而紫外吸收实验则呈明显的单链特征，辅以酶消化实验的结果，证实该病毒为单链RNA病毒。

NO elimination reactions are much complicated in the system of NO-CO-CO2-N2 with the existence of metallic oxides. Homogeneous reaction between NO and CO, reduction of NO by the lower valued metallic oxides, direct decomposition of NO as a catalytic reaction and catalytic reaction of NO/CO may all contribute in NO elimination.

金属氧化物存在条件下NO-CO-CO2-N2体系中，NO去除反应较为复杂，NO/CO气相直接反应、低价氧化物对NO的还原作用、金属氧化物对NO分解反应的催化作用及金属氧化物对NO/CO反应的催化作用等都可能存在。

The method is characterized in that: mixture of macromolecular dihydric alcohol and a dihydroxybutyl-terminated polydimethylsiloxane is dehydrated, added with diisocyanate for reaction, then added with a bis propionic acid, a dihydric alcohol chain extender and a catalyst - dibutyl tin laurate, and is diluted by acrylic ester; temperature reduction and emulsion are performed on the mixture after reaction; chain extension reaction is performed in water by a multi-amine chain extender, and siloxane modified polyurethane dispersoid which contains acrylic ester monomer is prepared; and an initiator - potassium persulphate is added into the siloxane modified polyurethane dispersoid for emulsion polymerization.

特征是先将大分子二元醇与二端羟丁基聚二甲基硅氧烷的混合液脱水后加入二异氰酸酯，反应后加入二羟甲基丙酸、二元醇扩链剂和催化剂二月桂酸二丁基锡，并用丙烯酸酯进行稀释，反应后降温乳化，用多元胺扩链剂在水中进行扩链反应，得到含有丙烯酸酯单体的硅氧烷改性聚氨酯分散体，然后再通过加入引发剂过硫酸钾进行乳液聚合。

The effects of reaction temperature ,reaction time and dosage of catalyst on the oxidation reaction were examined.

考察了反应温度、反应时间和催化剂用量对氧化反应的影响，找到适宜的氧化反应条件。

The result showed that the optimum reaction conditions were as follows: molar ratio of BPAD to ECH 1:15, reaction temperature 80 ℃, reaction time 6 h and the product DGEBAD had high epoxy value and yield (0.376 mol/100 g and 147.1% respectively).

结果表明，DGEBAD最优合成反应条件如下：BPAD与ECH物质的量比为1：15，反应温度80℃，反应时间6 h，所得DGEBAD具有较高的环氧值和产率（分别为0.376 mol/100 g和147.1%）。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新