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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。

At lower temperature, the interaction between the Ir particles and the adsorbed ethoxyl species is not strong enough to abstract H atom from the nearby CH3 group, and thus acetaldehyde acts as the key intermediate. Acetaldehyde can decompose to methane and CO and/or convert to acetone through decarbonylation.

低温时Ir粒子与吸附的乙氧基的相互作用的强度不足以从-CH3基团中提取H原子，此时乙醛是关键的反应中间物，乙醛可以裂解生成甲烷和一氧化碳或脱羰基生成丙酮。

It is discovered that metal protectant and polar polymer can reduce fretting wear of complex lithium grease largely by utilizing Fafnir friction oxidation tester investigates fretting wear of complex lithium grease .

用费夫纳摩擦氧化试验机考察复合锂基润滑脂的微动磨损时，发现金属保护剂和极性聚合物可大幅度降低复合锂基脂的微动磨损。

The apparatus for converting side-to-side to rotational motion for a workpiece includes a spring assembly with a movable base mounting element which is driven in a slightly arcuate reciprocal side-to-side motion and a fixed mounting element spaced apart from the base element and mounted in the appliance so that it does not rotate or move in operation of the apparatus.

一种将工作件的侧向运动转换为旋转运动的装置，包括弹性组件，带有作微小弧线往复侧向移动的可移动的基体固定件，和与基体件间隔开的固定的固定件，其固定在器具上在器具操作时不会转动或移动。

The results showed Antioxidant activity was very strong; at the concentration of 0.10g/L, The inhibition rate of superoxide anion free radical(Osuperscript – subscript 4 was 48.45%, The scavenging rate of hydroxyl free radical was 67.52%. Adding 0.1% of the extracts to lard, its antioxidant activity was better than that of 0.02% BHT. The extracts from peel showed higher activities than from juice.

结果表明：荸荠皮提取物的有明显的抗氧化活性，当浓度为0.10g/L时，对超氧离子自由基O(上标–下标 4的抑制率为48.45%，对羟自由基的清除率为67.52%，其0.1%提取物对猪油的抗氧化效果优于0.02%的抗氧化剂BHT，且其活性具有剂量效应关系。

On the NiO/SiO〓 catalyst prepared by IM, the main hydrogenation product of MA was SA, the activity and selectivity were almost no relation with the nickel content and nickel species 3. Summarizing the characterization and activity evaluation of the catalysts, we concluded: On nickel based catalyst, when NiO was crystallite, and the Ni〓 that was prepared by reducing, hydrogenation of the MA could lead to SA but not to γ-BL; when NiO was cluster and had a properly interaction with the support, the Ni〓 prepared by reducing, could hydrogenate MA to SA then to γ-BL. When NiO cluster and crystallite were both existed on the catalyst, the hydrogenation products were mixture of SA and γ-BL, and the amounts of SA and γ-BL were related with the ratio of cluster and crystallite.

综合催化剂的表征和活性评价得出：当镍基催化剂上氧化镍以结晶态存在，经氢还原后的零价镍可使顺丁烯二酸酐加氢得到丁二酸酐，丁二酸酐难以进一步加氢为γ-丁内酯；当镍基催化剂上氧化镍以簇团形式存在，与载体之间有适当的相互作用时，经氢还原后的零价镍可使顺丁烯二酸酐加氢得到的丁二酸酐进一步加氢为γ-丁内酯；若催化剂上氧化镍既有结晶态又有簇团形式时，随二者含量比例不同而得到丁二酸酐和γ-丁内酯的混合物。

Based on the low-velocity impact test, 4 major modes of low-velocity impact damage including delamination and matrix cracking were taken into account FEM simulation.

从z-pin增韧复合材料层合板低速冲击实验出发，考虑了复合材料层合板在受低速冲击时的分层及基体开裂等四种损伤形式，引入适当的损伤判据，对T300/3234碳纤维树脂基复合材料层合板的低速冲击损伤过程进行有限元模拟。

Based on the low-velocity impact test, 4 major modes of low-velocity impact damage including delamination and matrix cracking were taken into account FEM simulation. By using appropriate failure criterion, the low-velocity impact damage of z-pin reinforced laminates can be identified.

从z-pin增韧复合材料层合板低速冲击实验出发，考虑了复合材料层合板在受低速冲击时的分层及基体开裂等四种损伤形式，引入适当的损伤判据，对T300/3234碳纤维树脂基复合材料层合板的低速冲击损伤过程进行有限元模拟。

If an improper basis function is adopted for decomposing signals, the fault feature information can be weakened.

小波基函数的选择直接影响故障特征的提取效果，如果在信号分解时采用了不合适的基函数，会冲淡故障特征信息。

When they left St.Louis in 1804 to find a water route to the Pacific, no one knew how extensive the Rocky Mountains were or even exactly where they were, and the land beyond was terra incognita.

当他们在1804年离开圣路易斯去寻找一条通往太平洋的水路时，没有人知道洛基山脉有多广阔，甚至没有人知道洛基山脉确切的位置，山的那一面更是一个未知的土地。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失