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Then the protected D-mannitol, mixed with lead tetraacetate, hippuric and acetic anhydride, were refluxed in THF for 18 h in a one-pot two step reaction to afford a chiral precursor-2-phenyl-4-[-2,3-O-]-propylidene-5(4H)-oxazolones.

产物与四乙酸铅、马尿酸、乙酐于THF中回流18 h完成一釜二步反应，纯化后得到含有手性碳原子的环丙烷氨基酸前体-2 苯基-4-[-2，3-O-]丙叉？

The precursor of the modern car was a horseless carriage with a petrol engine.

现代汽车的前身是不用马拉的，装有汽油发动机的车子。

The precursor of the modern car was a horseless car riage with a petrol engine.

现代汽车的前身是不用马拉的，装有汽油发动机的车子。

The preparation method comprises the steps as follows: houghite ZnAl-NO3-LDHs is taken as the precursor, ion exchange method is adopted to insert the 2- naphthylamine-1, 5-disulfonic acid to the interlayer of ZnAl-NO3-LDHs, thereby assembling and acquiring the ZnAl-NADA-LDHs of good crystalling phase structure and splendid performance.

超分子结构2-萘胺-1，5-二磺酸插层材料，简写为ZnAl-NADA-LDHs，其分子式为：[Zn 2 1-x Al 3 x 2 ](C 10 H 7 NO 6 S 2 ) 2- x/2 mH 2 O，是以水滑石ZnAl-NO 3 -LDHs为前体，采用离子交换法将2-萘胺-1，5-二磺酸插入到ZnAl-NO 3 -LDHs层间，组装得到晶相结构良好、性能优异的ZnAl-NADA-LDHs。

Specific contents and main conclusions are shown as follows:(1) The influence of precipitant on the properties of YAG:Ce phosphor was investigated. The precursor has good dispersity, when selecting ammonia hydrocarbonate as precipitant.

主要研究内容及结论如下：(1)研究了沉淀剂对前驱体制备的影响，结果表明：碳酸氢铵作沉淀剂制备的前驱体分散性好，煅烧过程中直接转变为YAG相，没有杂相生成。

Leaf-feeding resistance to this insect is conditioned by increasing tissue concentrations of benzoxazolinones and their precursor hydroxamic acids.

对这种害虫取食叶片的抗性决定于组织中苯并邅唑啉酮及其前体氧、肟酸浓度的增加。

The performace of material was tested by DSC,XRD,SEM,EIS and charge-discharge cycles . The influences of various synthesized condition , sintering time and the amount of F were studied and correlative technics parameter to improve performance of material were optimized. DSC shows that three endotherimc peaks and one large exothermic peak are observed in the temperature range 150-400℃, which is because of the removal of water,the decomposition of the organic constituents and the formation of spinel. Only the citrate precursor is sintered at least 450℃, the crystallinity of spinel phase could be formed intactly.

通过DSC、XRD、SEM、EIS和充放电循环等手段对材料进行性能测试，比较了不同合成温度、烧结时间和不同掺杂元素量等条件对材料性能的影响，优选出提高材料性能的相关工艺参数， DSC表明，采用溶胶-凝胶-络合法制备的前驱体在150-400℃中有三个小的吸热峰和一个大的放热峰，这是前驱体中的水分、柠酸酸及其盐和醋酸及其盐在蒸发及分解，柠檬酸前驱体至少需在450℃以上才可能形成完整的尖晶石材料。

From the experiment results,it is concerned that the thin film was composed of many small particles(most of them was with a size between 20 and 30 nm)uniformly deposited and intervein on the substrate surface. Some large particles were tightly embedded into the thin film.The deposition rate increased by increasing the precursor flow rate and the discharge power.

以上的分析结果表明：常压等离子化学气相沉积得到的薄膜是一种由众多小颗粒(其中主要为尺度在20-30nm的颗粒)的颗粒串联形成的网孔结构，并且在薄膜生长过程中一部分的颗粒被包埋在其中，薄膜颗粒分布较均匀。

The microcapsules with polyurea shell for functionally thermal fluid application were synthesized by interfacial polymerization with isophorone diisocyanate and tetraethylenepentamine as wall material precursor in an emulsion system.

1前言功能热流体是在单相流体中混入其它材料形成的一种集储热与强化传热功能于一身的新型储传热介质[1]。

Simvastatin is a cholesterol lowering agent that is partially synthesized from lovastatin. Simvastatin is an inactive lactonization precursor parmaceutical, it operate by active metabolites or its derivatives via liver hydrolyzation.

辛伐他汀是疗效确切的调血脂药物，能有效降低冠心病的发病率和死亡率，已列入国家基本药物，在冠心病的一级和二级预防中，作为治疗高胆固醇血症的首选药物。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。