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Thecompositions of raw material and products were identified with GC-MS, the results indicatedthat the products were composed of (β-acryloxyl ethyl) esters of dihydropimaric acid anddehydrogenated abietic acid, and their relative amounts was consistent with the amount ofdihydropimaric acid and dehydrogenated abietic acid in the disproportionated rosin.

论文还采用GC-MS对原料和产物的组分进行了鉴别，结果表明酯化产物由二氢海松酸酯和脱氢枞酸酯组成，且其相对含量与歧化松香中二氢海松酸和脱氢枞酸组成基本一致。

All the compounds were isolated and identified from the bituminous coals for the first time, bis(2-ethylheptyl) terephthalate and 18-ethyl-17-(hexan-2\'-yl) docosanoic acid are new compounds.Further more, a Colourless Oil Liquid, a white acerate crystals containing some alkanes, a white tabular crystals consisting of some fatty acid esters and a white powder crystals in which some fatty acids exist were isolated and analysed by GC/MS for the first time.Through this research, a study method of"classification extract of bituminous coal- separation with silica-gel and gelatin column chromatographies- identification of the isolated compounds by FTIR, GC/MS, LC/MS, 1H NMR and 13C NMR analyses"was established and proved to be a practical approach toward separable and non-destructive identification of some organic compounds in bituminous coals for coal chemistry research.

本研究建立了&原煤分级萃取-硅胶与凝胶柱层析分离与纯化-GC/MS或LC/MS检测-FTIR、MS、1H NMR和13C NMR波谱解析&这一煤中有机化学成分的非破坏性分离与分析的研究方法，并验证该研究方法有效可行。

The E-TOF will also be feasible and practical to assist chemists in screening the optimal reaction condition or evaluating the overall efficiency of different catalytic systems for a specific asymmetric reaction.4.For the first time,we explored chiralγ-hydroxy-α,β-acetylenic esters,which were prepared via asymmetric alkynylation,as key intermediates to the synthesis of chiralγ-butyrolactones. This convergent and enantioselective approach to chiralγ-butyrolactones is practical and easily handled with protecting group free.

这一概念包括反应产率、对映选择性、配体用量以及反应时间四个重要反应参数，不仅适用同一反应不同催化体系的横向综合性评价，而且适用于某一特定反应催化体系的优化过程，有助于研究人员选择最佳的反应条件。4、我们发展了以手性γ-羟基-α，β-炔酸酯为关键中间体完成了手性γ-丁内酯类天然产物的对映立体选择性全合成，该关键中间体能够以我们的催化体系方便的对映选择性合成，之后的官能团转换方法成熟，易于操作，无需进行繁琐的官能团保护和脱保护过程，绿色经济。

With 1,2-dimethoxyethaneas an additive,the reaction proceeded under mild condition to gave the highly functionalizedγ-hydroxy-α,β-acetylenic esters,and highly toxic reagent was avoided.

以DME为添加剂使不对称合成手性γ-羟基-α，β-炔酸酯的反应条件更加温和、易于操作，避免了剧毒物质的使用。

Aromatic and aliphatic aldoxime s could be efficiently converted into the corresponding carboxylic acid esters by treatment aldoxime s with an alcoholic solution of 30% hydrogen peroxide in the presence of catalytic amounts of polystyrene-bound phenylseleninic acid.

在30%双氧水和醇组成体系中，聚合物负载的苯亚硒酸试剂可有效地促进过氧化氢氧化肟转变成羧酸酯；相应伯醇和仲醇的羧酸酯的产率中等到良好，但在含叔醇的体系中没有相应的羧酸酯生成。

The one-pot two-step process was convenient for aldose amidation with amino esters.

另外，一锅两步化的加料顺序，对於醛醣与胺基酯键结十分重要。

The general formulas of these compounds are as follows:The strobilurin derivatives were synthesized from substitutedβ-keto esters (2) as starting material which were prepared from substituted ketones (1) and dimethyl carbonate. The ester (2) and methyl hydrazine or substituted amidine were dissolved in methanol and the mixture was heated to reflux to obtain the substituted 5-hydroxy-1H-pyrazole (3) or 4-hydroxy-pyrimidine (4). The title compounds were prepared by reacting the intermediates (3 and 4) with substituted halomethylphenyls which contain four active group under basic conditions.

本论文所合成的strobilurin化合物均是以β-酮酸酯类化合物(2)为起始原料合成的，该中间体(2)是由酮类化合物(1)与碳酸二甲酯在碱性条件下反应生成的，中间体(2)与甲基肼或取代脒类化合物在甲醇中回流制得取代的1H-5-羟基吡唑(3)或4-羟基嘧啶(4)，中间体(3和4)再与包含四种活性基的苄卤中间体在碱性条件下制得目标化合物。

The genera formulas of these compounds are as follows:The strobilurin derivatives were synthesized from substitutedβ-keto esters (2) as starting material which were prepared from substituted ketones (1) and dimethyl carbonate. The ester (2) and methyl hydrazine or substituted amidine were dissolved in methanol and the mixture was heated to reflux to obtain the substituted 5-hydroxy-1H-pyrazole (3) or 4-hydroxy-pyrimidine (4). The title compounds were prepared by reacting the intermediates (3 and 4) with substituted halomethylphenyls which contain four active group under basic conditions.

本论文所合成的strobilurin化合物均是以β-酮酸酯类化合物(2)为起始原料合成的，该中间体(2)是由酮类化合物(1)与碳酸二甲酯在碱性条件下反应生成的，中间体(2)与甲基肼或取代脒类化合物在甲醇中回流制得取代的1H-5-羟基吡唑(3)或4-羟基嘧啶(4)，中间体(3和4)再与包含四种活性基的苄卤中间体在碱性条件下制得目标化合物。

A series of novel bile acid derivatives as potential hepato-biliary and intestinal scintigraphy imaging SPECT (single photon emission computed tomography) tracers were prepared from bile acids by es-terification, aminolysis of esters and alkylation of amino groups.

以胆酸、鹅去氧胆酸为起始原料，经羧基的酯化、酯的胺解以及氨基的烷基化，合成了一系列潜在的针对肝胆显像和肠显像的SPECT (Single photon emission computed tomography)分子探针前体。

In search of environmentally benign insecticides with high activity, low toxicity and low residue, a novel series of anthranilic acid esters containing N-pyridylpyrazole were designed and synthesized. All of the compounds were characterized and confirmed by IR, 1H NMR, MS and elemental analysis.

设计，合成了8个新的含N-吡啶基吡唑杂环的邻氨基苯甲酸酯类化合物，结构经FTIR， MS， 1H NMR 和元素分析确证，并且采用X-射线衍射分析方法确证了具有较好生物活性的化合物14d的结构。

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。