The Mannich reaction is one of the most widely used reactions in organic chemistry, and also one of the first examples of a multicomponent reaction already described on the literature. This reaction results in 尾-aminocarbonylated compounds which allow the generation of several structures that can ...
aSo I don't wanna close my eyes tonight [translate] aWhy oh why [translate] aexamples of nondegradable pollutants are mercury ,lead and some of their compounds and some plastics nondegradable污染物的例子是水银,主角和一些他们的化合物和一些塑料 [translate] ...
aPlease provide examples of part numbers and part descriptions - or description of manufacturer's products 请提供零件号码的例子并且分开描述-或描述制造商的产品[translate] abest job ever 最佳工作[translate] a新增了两个项目 Increased two projects[translate] ...
In the presence of AlCl3, compound 12 rapidly rearranged to 1-benzyltetralin (23) and 2,3:6,7-dibenzobicyclo[3.3.1]nona-2,6-diene (16). The mechanistic implications are discussed in light of thermodynamic stability of the compounds. Some examples of the cyclodehydration of tertiary 4-...
Some examples are the use of seed dressing with mercury compounds in some countries, use of dimethylmercury in small amounts [...] zeromercury.org 比如,某些国家使用汞 化合物拌种,使用少量二甲基汞作为一些化学检验的参考标准,以及自 20 世纪 30 年代以来使用硫柳汞(含乙基汞)作为一些疫苗和其它...
Some examples of their extensive diversity are given below: @@@[Equation] Ok, but surely the phase diagram and the structural details were worked out years ago? As it turns out, until the recent effort to make Freon substitutes, most of the purported AlF 3 phases were known only from ...
the city has literally seen its way clear to having no water quali-ty problems. Other mid-western sites are now using EDR systems as large as 6.2 mgd to treat for radium and hardness reduction at water recoveries up to 85%. Today, there are many other examples of cities, towns and muni...
What properties characterize ionic compounds? What mineral commonly forms porphyroblasts? What are examples of silicate minerals? What are the properties of nonmetals? How do metals and nonmetals differ in physical properties? What determines the chemical properties of an atom?
sometime 意思是: 某个时候; 晚期古英语,sumtime,“在某个时候或另一个时候;”参见some + time(n.)。 “在一个不确定的未来时间”这个意思来自14世纪后期。作为形容词,“前任,晚期,曾经,在过去的某个时间”,15世纪后期。中古英语中也有sumtide(14世纪早期)。比
21.Give examples of situations in which a usage generally considered non-standard(e.g.ain't)would be acceptable,even appropriate. In the talks between intimate friends,one may say“gimme that!”instead of“give me that!”and“wachya doin'?”instead of“what are you doing?”and this list...