查询词典 addition

The dissertation mainly consists of two parts:1. The Reaction Chemistry of Alkynes under Palladium Catalysis Part 1 studies the reaction α,β-unsaturated carbonyl compounds with alkenylpalladium intermediate generated by nucleopalladation, and discovered 1 the Pd-catalyzed tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls,2 the four-component tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls, 3 the tandem intramolecular oxypalladation-conjugate additionreaction of alkynoic acids with α,β-enals. These new reactions provide notonly efficient highly stereoselective methods for the synthesis of γ,δ-unsaturated,polyunsaturated carbonyl compounds and γ-lactonic aldehydes, but also thebasic transformations for a number of C-C bond formation reactions which can be usedto design synthesis of many acyclic, cyclic or polycyclic compounds.

本论文的主要工作分为两个部分：一、钯催化下炔烃的反应化学在本小组前人工作的基础上，我们详细研究了炔烃亲核钯化产生的烯基钯中间体与α，β-不饱和羰基化合物的反应，发现两价钯催化下卤离子-炔烃-α，β-不饱和醛酮的串联加成反应、卤离子-炔烃-α，β-不饱和醛酮的西组分串联加成及炔酸分子内氧钯化-串联Michael型加成反应；由此发展了γ，δ-不饱和醛酮、多不饱和羰基化合物和带有醛酮基侧链的γ-丁内酯衍生物的高立体选择性合成方法，这一过量卤离子存在下的烯基钯对α，β-不饱和羰基化合物共轭加成反应的发现，为大量碳-碳键形成反应的实现提供了基础，使我们能够从这一基本反应出发，设计和开发多种分子内、分子间的碳碳成键反应，以好的立体、区域选择性组建开链、环状及多环类型的化合物。

To avoid the low yield in direct hydrosilylation addition of allyamine, 1, 1, 1, 3, 3, 3-hexamethyldisilazane is used to protect the amino groups, and the protective groups are removed easily after hydrosilylation addition, then the high yield of ladderlike copolymethyl-aminpropylsilsesquioxane was obtained.

为了克服将烯丙基胺直接与聚氢基甲基倍半硅氧烷进行硅氢加成反应接枝效率低的缺点，探索用六甲基二硅氮烷对烯丙基胺预保护，硅氢加成反应后再脱保护，从而以较高产率制备了含胺丙基、甲基的反应性梯形共聚倍半硅氧烷。

Because of addition of ACR, mobility of copolymerization resin becomes better than that of pure PVC.The synthesis of ACR latices were enlarged, and they were grafted with vinyl chloride, results indicate the copolymerization resin has better modified effect and steady properties .In addition, the main design parameters of a 1m3 autoclave were designed, it made an preparation for enlarging experiment of suspension copolymerization.

对ACR胶乳进行了放大实验，并与氯乙烯进行了接枝和共混，所得树脂改性效果良好，性能稳定，为工业化生产奠定了基础，另外，对1m~3反应釜的主要参数进行了设计，为悬浮接枝的放大实验做准备。

Most technically exciting was the FD (Mark-4) radar, with the addition of precision elevation sensing by the addition of vertical antenna lobing.

由于增加了垂直方向扫描，它能提供仰角数据。

Combined with the observation of the metallograph and analysis of the change of chemical composition of alloys,we can draw the following conclusion:the addition of within the range of 40% once-used cobalt-chromium alloy to casting cobalt-chromium alloy wouldn't affect the quality of restorations,excessive addition of once-used alloy would damaged the microstructure and physical properties.

摘 要：通过比较不同比例的新旧钴铬合金铸造后的抗拉强度、屈服强度、延伸率、硬度等机械性能指标，并结合相应的金相观察及化学成份分析，得出结论：铸造钴铬合金中可加入不超过40％的仅铸造过一次的旧料而不影响合金的主要机械性能，超过这一比例，将影响修复体的质量。

As the addition of experience, the addition of experience, return those who have superior of each person of the same trade to enjoy a face, after becoming a friend with them, I just discover I am a genuine a person with a very limited outlook, what understanding is black cat white cat, what is the cat that passes more moistly.

随着经验的增加，经验的增加，还有各位同行高手的赏脸，和他们成了朋友后，我才发现我是一个地地道道的井底之蛙，了解到什么是黑猫白猫，什么是过得比较滋润的猫。

A second group includes those compositions, which include an organic polymeric binding material, eg, mixed cellulose esters of monobasic or dibasic acids such as cellulose acetate succinate; an addition-polymerizable ethylenically unsaturated compound, eg, vinylidene and vinyl monomers, preferably of the acrylic or alkacrylic ester type; eg, triethylene glycol diacrylate; and an addition-polymerization initiator which forms radicals under the influence of actinic radiation, eg, anthraquinone.

第二组包括那些作品，其中包括有机聚合物具有约束力的物质，例如，对一元或二元酸混合纤维素酯，如醋酸纤维素琥珀酸； 1此外，聚合ethylenically不饱和化合物，例如，偏和乙烯基单体，丙烯酸最好的或alkacrylic酯类型，如，三乙二醇二丙烯酸酯；和加成聚合引发剂的形式下光化辐射的影响自由基，例如，蒽醌。

The morphological observation showed that the two monosomic addition lines could form head normally, but the characters existed difference between the addition- lines and diploid parent.

对2个单体异附加系的植株形态学性状进行了初步观察，结果显示2个附加系均能正常结球，但球形的形态与二倍体结球甘蓝存在明显差异。

Interspecies hybridization and backcrossing is a means to transfer desirable genes from one species to another in breeding programs of higher plants. Monosomic alien addition lines can be produced via addition of single chromosome of an alien donor species to the entire chromosome complement of the recipient species.

在高等植物中，以种间杂交和回交把有益基因从一个物种转移到另一个物种为目的育种项目中，单个外源染色体常常被附加到含有受体细胞完整一套染色体中，形成异源单体附加系。

We have factories in practice in order to save money, I used a famous brand does not, in the course of an operation that we have adopted me on what kind of way, as long as an addition to the dirty, it will be in addition to the formation of dirty location like the waves around some of the blue color that's not the same as nonanatomical.

我们操练工场在此刻曾不纬为了耗费收出，搁置了某一品牌并不不出名的印版，在不不安作历程洋我论我们拔取什么样的办法，只要一不兴不净，它不离会在不兴不净场所的边际变成一些象波浪差别不法规的蓝底色。

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