查询词典 ions

Master the Keto-Enol tautomerism; reactions of enols:α-H substitution reactions;α-halogenation of aldehydes and ketones;α-bromination of carboxylic acids; acidity ofα-H atoms: enolate ion formation; reactivity of enolate ions; alkylation of enolate ions; mechanism of carbonyl condensation reactions;condensations of aldehydes and ketones: the Aldol reaction; dehydration of Aldol products; the Claisen condensation reaction; the Michael addition.

熟练掌握酮式－烯醇式互变异构；烯醇的反应：α-H的活性；醛酮的α卤代反应；羧酸的α-溴代反应；α-H的酸性：烯醇负离子的形成；烯醇负离子的反应；烯醇负离子的烃基化；羰基化合物的缩合反应机理；醛酮的缩合反应－Aldol缩合；Aldol缩合产物的脱水反应； Cleisen 酯缩合反应；麦克尔加成反应。

In chapter four,the cooperative vibronicspectra of terbium in manyRE ions' complexes are studied,much information about the coordination ofterbium ions are obtained.

第四章研究了许多稀土离子铽的配合物的电子振动光谱，得到了许多有关铽离子的配位信息。

As metal ions can interact with both of ADM and DNA, they undoubtedly affect the interaction between ADM and DNA. Addition of a large excess of Cu or Fe into a solution of well-formed ADM-DNA complex makes the metal ions simultaneously bind to ADM and DNA to form a ternary complex. Otherwise,〓 or 〓 complexes can bind directly to DNA to form a ternary complex.

金属离子-ADM-DNA三元体系的光谱研究表明，当ADM与DNA结合后，大量Cu或Fe的加入可以使金属离子进入到ADM-DNA复合物中，并同时与ADM和DNA键合，形成三元复合物；反之，若ADM先与Cu或Fe配位，生成的金属配合物则能够直接与DNA结合形成三元复合物。

Its specific procedures are :first to treat the sample with hydrofluoric acid to convert the silica into a gas of silicon tetrafluoride to escape, and then at a PH value of 4 to 5 to treat the residual liquid with hydroxylamine hydrochloride to get the ferric ions reduced to ferrous ions.

其具体步骤为：首先用氢氟酸处理试样，使沉淀法白炭黑转化成四氟化硅气体逸出。

According to the H NMRstudy, it was found that the protons on the cyclopentadienyl ring of 〓 were not splitted, but when one proton on the cyclopentadienylring was substituted by methyl, that is in〓 complexes, thefour protons on the ring were splitted into four groups,the 〓 between the onesignal and the others is large, the total splitting is over 2ppm. The splittings werealso affected by the halides linked with the titanium, they increase according to theorder of CI, Br, I. By the study of the 〓 Sn NMR, it is found that the chemicalshifts of 〓 are present in low field. It is assume that the large space strain causesthe angles of the tin linked with ligands deviate from the normal tetrahedral anglesresults low field shift for 〓Sn. And by MS study,there were no molecular ions for 〓 complexes in the spectra. However, for 〓 when X=CI,Br,NCO and Ar is tolyl or phenyl group,there were molecular ions,but theirabundances were very small,and no that for the iodide was found.

钛上的卤素对茂环氢的裂分也有影响，依〓，Br，I顺序，卤素对茂环氢的裂分依次加大；通过对〓的研究发现，以上这些化合物〓的化学位移都出现在低场，认为大的空间张力造成的锡的键角偏离正常的锡的四面体键角是造成〓化学位移出现在低场的原因；对这些化合物质谱的研究发现，〓系列化合物得不到分子离子峰，而〓系列的化合物，当X=〓，NCO和苯环上不带取代基或只带甲基时，则出现分子离子峰，但丰度很低，而相应的碘化物和其它化合物则没出现分子离子峰。

In the aluminum solution ,the trivalence aluminum ion combines with water to form the coordination compound and then the coordination waters hydrolyze into hydroxide ions. The hydroxide ions can join up each other by the hydroxide ion bridges so that the double cores, three cores and multiple cores coordination compounds are formed.

另一方面，在这种铝盐溶液中，三价铝离子是以铝水配合物的形态存在，配位水发生水解生成羟基配离子，其通过羟基桥联结，放出水分子，并逐级由单体配合成双核、三核以致形成多核羟基配合物。

Especially, the uniformization effect of Na+ ions is better than that of K+ ions.

推测Na离子的作用是消除了PbF2：Gd晶体中因Gd离子的掺杂而造成的间隙F离子，从而使晶体中的缺陷浓度大大降低。

For H_2~+ molecule, the basic theory model is the same as that for a single proton, but adding in the interactions of fragment ions, concluding Coulomb forces and wake-like interaction. Then the trajectories of each of the fragment ions can be simulated in order to further study the vicinage effect.

对于氢分子离子在碳纳米管中的库仑爆炸过程，基本理论模型与求解单个离子时所采用的相同，但是考虑了离子之间的相互作用力，包括库仑相互作用与尾流效应，计算出分子离子中每个离子的运动轨迹，从而对邻近效应进行分析。

When pH is 5 or so, molecules and ions of xanthate account for 50% respectively .While pH is above 5, the major effect is from ions, or from molecules.

离子的吸附作用是主要机制，在pH值较大时效果显著，但不能排除氢氧化物的沉淀作用。

Fluoride ions caused widespread endemic fluorosis in humans, but little attention was paid to the effect of fluoride ions on aquatic organisms. Semi-static acute toxicity trial on larval Siberian sturgeon Acipenser baeri was carried out to explore the safe criteria of fluoride to fish.

为检测氟对鱼类的生态毒性效应，在水温（17±1）℃的条件下，采用半静态式生物毒性试验方法研究了氟离子对西伯利亚鲟初孵仔鱼的急性毒性效应（氟离子浓度梯度设置为0、100、200、300、400、500、600mg·L-1）。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。