查询词典 esters

Result The results showed that its components were quite complex, and 89 organic compounds were identified. There were 72 kinds of oxygen-containing organic compounds which included esters, phenols, aethers, ketones and alcohols in the depolymerization product, small amounts of alkanes, alkenes, arenes, thiophenol and nitrogen-containing organic compounds were also detected, which showed that characteristics of the product with high oxygen content, low nitrogen and sulphur content.

结果］超临界乙醇解聚产物成分十分复杂，GC/MS分析鉴定出89种有机化合物，其中72种为含氧化合物，主要有酯、酚、醚、酮和醇等，还检测出少量烷烃、烯烃、芳烃、苯硫酚和含氮化合物，反映了解聚产物的高含氧量和低含氮硫量的特性。

Second, using DBU as the base for enolization of propargylic esters of unsaturated acids 18e-k, we developed a tandem Ireland-Claisen rearrangement /isomerization reactions. It has been shown that the reaction sequence affords triene molecules 42a-b and 43a-b in moderated to high yields. Interestingly, with allyl hexa-3,5-dienoates 18i-j as the substrate, the rearranged products underwent further aromatization to give uniquely substituted benzyl acids 44a-b.

其次，以含有活泼质子的烯酸炔丙酯18e-k为底物，在DBU为烯醇化碱、TMSCl为硅试剂的条件下，底物18e-h发生了Ireland-Claisen重排/异构化串联反应，得到完全共轭的三烯类化合物42a-b及43a-b；而以己二烯酸炔丙基酯18i-j为底物时，重排/异构化后的产物进一步发生电环化等反应最终得到芳构化产物——取代苯甲酸类化合物44a-b。

Triphenyl phosphite provided prominent stabilization only when used in combination with other stabilizers. Good results have been obtained for both polyether-urethane and nitrate esters when using 2,6-di-t-butyl-4-methyl-phenol as stabilizer.

亚磷酸三苯酯单独使用时效果较差，但与其它种类的稳定剂混合使用能得到较好的效果。2，6-二叔丁基-4-甲基酚对硝酸酯和聚氨酯粘结剂均具有良好的稳定作用。

As suitable solvents for applying a coloring substance which is, eg, a triphenylmethane dye, organic liquids such as aliphatic alcohols, ketones, esters and aromatic hydrocarbons can be used.

至于申请一着色物质，例如，一三苯甲烷染料，如脂肪醇，酮，酯和芳香族碳氢化合物有机液体可以使用合适的溶剂。

Molecular mechanics was introduced into the field of molecular recognition of chiral SalenZn for the first time. The minimal energy conformations of host-guest system were obtained with Tripos force field. The difference of the energy of L and D-amino acid esters system was mostly attributed to the difference of electrostatic energy.

首次将分子力学的方法引入手性Salen金属配合物的识别研究体系，用Tripos力场研究了主体Salen-Zn与氨基酸酯缔合后的体系最低能量构象，分析了L、D型两个体系能量差异的主要来源，即分子识别的主要根源是静电能的差异。

The descriptions of 300V and 8100 X-lite have only uninformative words about "100% Synthetic - Double Ester Technology" or "100% Synthetic - Ester Based", but how much esters contained in motor oils exactly?

在300V和8100 X-lite的包装说明上有著不太资讯化的字眼有关100%合成油-双酯科技或者100%合成油-酯类基础油，但有多少比例的酯类在这机油内呢？

The results showed that there were 8 kinds of aliphatic, 5 kinds of esters, 2 kinds of aldehydes, 2 kinds of nitrogen sulfur heterocyclic rings and one kind of hydrocarbon, alcoholics, ketone, lactones respectively in the analyzed 21 kinds of aroma components, and the content of furfural,β-methyl valeric acid, palmitic acid, nicotine, neohytadiene were higher, next were acetyl ethyl propionate, caleric acid, phenyl ethyl acetate, hydroxylic diethyl succinate.

结果表明，在分析出的21种香气成分中，分别有脂肪酸类8种，酯类5种，醛类2种，氮硫杂环类2种，烃类、醇类、酮类、内酯类各l种，其中相对含量较高的物质成分是糠醛、β-甲基戊酸、十六碳酸、烟碱、新植二烯，其次是乙酰丙酸乙酯、异戊酸、苯乙酸乙酯、羟基丁二酸二乙酯等。

Esterification process of a reversible step wereresolved as two irreversible steps,then chemical decomposition of wood components weredecreased in liquid acid catalyst.Experiments showed that crosslinking catalysts took catalysisrole on two process in the esterification,(1)five cyclic anhydrides formed by dehydration ofpolycarboxylic acids,(2)esters occurred by substitution between five cyclic anhydrides andwood.

实验中的反应过程使一般的酯化一步可逆反应，分解为两步不可逆反应，减少了液相酸催化过程的木材组分化学降解；交联反应催化剂对于多元羧酸类化合物与木材组分的酯化反应具有两个过程的催化作用：(1)多元羧酸脱水形成五元环酸酐中间体；(2)木材与五元酸酐中间体亲核取代反应形成酯。

Therefore esterification crosslinked reactionbetween polyearboxylic acid and wood can be quantitatively determined.According toexperiment results of stereoscopic configuration choices by crosslinking agents,crosslinkingreaction between model of reaction intermediate and wood,and the intermediate characteristic incrosslinking reaction,crosslinking reaction intermediate was proofed.We can infercrosslinking reactions between polycarboxylicacid and wood want through a mechanism of twosteps reaction process,the first cyclic anhydrides were formed as intermediates by dehydratingbetween hydroxyls in polycarboxylic acids,second esters were occurred by substitution reactionbetween wood hydroxyls and cyclic anhydrides.

从而可全面定量表征木材与多元羧酸类化合物的酯化交联反应；依据交联剂立体构型选择性、反应中间体模型物与木材的交联反应和交联反应中间体的波谱特征实验结果，证实了交联反应中间体，因此可以推测：多元羧酸类化合物与木材化学组分的交联反应是经历两步反应的机理，首先多元羧酸中相邻羧基的羟基之间脱水形成五元环酸酐中间体，然后木材的羟基与酸酐发生亲核取代反应形成酯。

In a particular embodiment, a crop protection composition comprises a mononucleate solid crop protection particle coated with either wood rosin, rosin derivatives, waxes, fatty derivatives, sterols, long-chain sterol esters and sulfur.

在具体的实施例中，农作物保护组合物包括一种用木松香、松香衍生物、石蜡、脂肪衍生物、甾醇、长链甾醇酯及硫中之一加以包被的单核固体农作物保护颗粒。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。