查询词典 sulfur ether

In chapter four, the chiral recognition properties of one chiral calix [4] crown ether toward amygdalic acid and dibenzoyl-tartaric acid were studied by 〓H NMR,〓C NMR and UV-vis spectroscopy.

研究结果表明，手性杯[4]氮杂冠醚对二者均有一定的手性识别能力，并发现针对不同的客体，主体以不同的构象与之相互作用，证实分子识别过程中存在构象的变化。

Methods Intestinal flora of human, rat, Beagle dog, and rabbit and CME were anaerobically cultured at 37℃ in vitro. After being extracted by acetic ether, the main metabolites of CME were separated and quantified by HPLC.

采用人、大鼠、Beagle犬及家兔的新鲜粪便37℃厌氧培养，经醋酸乙酯提取后采用RP-HPLC及LC-MS方法对代谢成分进行分离和定性、定量分析。

Reaction (1) was examined with different kinds of acetal substrate(1) and vinyl ethyl ether, and the results indicated that the 1, 1,3-triethoxy compounds could be obtained in high yields of 88 and 97% respectively when the R groups of the acetal are phenyl and anisyl, while the yields amounted only to 55-75 % for R=a...

有证据表明这种催化反应也可能是通过正碳离子中间体进行的。本反应的产物1，1，3-三乙氧基化合物经乙酸/乙酸钠溶液水解可得反式α，β-不饱和醛。水解产率：芳香族产物大于90%，脂肪族产物大于75%。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巯基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巰基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

Under high dilution,the cross-coupling reactions of 4,5-dicyano-1,3-dithiol-2-one(6) and dithia crown-ether annulated tetrathiafulvalenes(3a～3c) in toluene gave asymmetrical dicyano tetrathiafulvalene derivatives(7a～7c) in the presence of triethyl phosphite.The compounds 7a～7c were characterized by(~1HNMR,EA,MS and IR.

在甲苯溶液中，在亚磷酸三乙酯存在下，采取高度稀释的方法，使4，5-二氰基-1，3-二硫杂环戊二烯-2-酮分别和多缩硫杂冠醚进行交叉偶联反应，成功地得到了不对称的2，3-二氰基四硫富瓦烯衍生物。

The contents of fat, glycogen, protein, RNA and DNA, in diapause pupa of Heliothisarmigera Hubner were determinated by ether extract method, anthroic ketone colorimetry,Folin-phenal method and ultraviolet absorption method respectively.

本文通过乙醚提取法、蒽酮法、Folin－phenal法和紫外吸收法分别测定了棉铃虫滞育越冬蛹在滞育期中脂肪、糖原、蛋白质、RNA和DNA含量的变化。

The separation of tocopherols and tocotrienols by using the method of adsorption chromatography on silica and on silica impregnated with silver nitrate have been discussed. Satisfactory separation could be obtained with argentation column chromatography by eluting batchwise with n-hexane containing increasing amounts of diethyl ether. More than 90% of vitamin E amount in eluate was tocotrienols.

以乙醚正己烷混合溶液为淋洗液，探讨了硅胶柱层析和硝酸银硅胶柱层析分离生育三烯酚和生育酚的效果，结果表明：通过改变淋洗液中乙醚含量可以将生育酚和生育三烯酚大部分分离：硝酸银硅胶柱层析分离生育三烯酚和生育酚的效果明显高于硅胶柱层析，其洗脱液中生育三烯酚可占V〓总量的90％以上，最高达98.47％。

The petroleum ether extacts,ethyl acetate extracts and methanol extracts from roots of Aristolochia debillis Sieb.et Zucc.

通过琼脂平板扩散试验和双倍稀释试验，对青木香Aristolochia debillis Sieb.et Zucc。

1The cardiac disturbances of hypothermic dog under ether anaesthesia showed the following types:ventricular fibrillation,asystole or asystolic fibrillation.

一在乙醚麻醉下，低温所致狗心脏活动障碍有三种型式，即心室颤动、心跳停止和心跳停止式心室颤动。

The Porsche Owner: But it's my car!

可，这是我的车呀。

LOX_83}{Oh, another bunch of wackos.

{LOX_83}{呃，又一群怪人。