查询词典 ortho

For three different reaction paths leading to ortho, meta, para-chloropyridine, two transition states have been located by PM3 on each reaction path, while only one transition state by ab initio, however both methods give the same results: the energy of transition state and activation barrier on producing 2-chloropyridine are the lowest among three reaction paths, so 2-chloropyridine is obtained priorly, which agrees with the experimental results.

生成邻、间、对氯代吡啶三条不同反应途径PM3方法优化得到两个过渡态，而从头算方法中只优化得到一个过渡态。但两种方法的研究结果均表明：三条反应途径中生成2-氯吡啶的过渡态能量和活化能最低，因此反应优先生成2-氯吡啶，与实验结果一致。

The reactions of benzaldehydes bearing an ortho substituent group on the phenyl ring with propargyl bromide may yield a mixture of regioisomers (homopropargyl and homoallenyl alcohols) or a single homoallenic alcohol due to the steric effect.

邻位上的取代基由于位阻原因往往使反应得到含有高丙二烯醇和高炔丙醇的混合物或者单一的高丙二烯醇。

It was found that with the increase of propionic/acetic acid ratio, the soluble ortho-phosphorus release and uptake decreased.

随丙酸／乙酸比例增加，SOP的释放与吸收量减少，SOP的代谢速率降低，但SOP的去除率明显增加。

Artificial acidification can be achieved by the addition of lactic, acetic , tartaric or citric acid to rye dough or by adding acidic forms of sodium and calcium salts of ortho- and\0r pyrophosphoric acids.

通过向黑麦面团中添加乳酸、醋酸、酒石酸或柠檬酸或添加酸性正磷酸和\或焦磷酸的钠盐和钙盐就可以实现人工酸化面团的目的。

Sing Scenedesmus obliquus entrapped in calcium-al-ginate gel for purifying sewage,this paper studied the purification efficiencies of ammonia-nitrogen and ortho-phosphate by immobilized algae and its changes of growth, the content of chlorophyll a, photosynthesis and per oxidase,and comparison with free algae.

将斜生栅藻包埋固定在褐藻酸钙凝胶胶珠中。对人工配制的污水进行净化，研究其对污水中氨氮和正磷酸盐的净化效率以及净化过程中藻类的生长，叶绿素α含量、光合强度和过氧化物酶活性的变化。

The results show high selectivity when the temperature is controlled at 50 CC , and the nitrated reaction time is 90 mm, toluene is nitrated by using 95% nitric acid as nitrating reagent at the presence of acetic anhydride, 1.0g silicotungstic acid catalyst is calcinated at 300℃ for 1.5h. The o/p (ratio of ortho to paro isomer of toluene nitration) ratio is 0.89 in product distribution of toluene nitration, lower than 1.67 using sulfonitric acid as catalyst. The yield of products is 91.6%.

结果表明，在醋酐存在条件下，以CCl4为溶剂，以质量分数为95%的硝酸为硝化剂，反应温度控制在50℃，反应60 min， 1.0g经300℃焙烧1.5h后的硅钨酸催化剂，对甲苯表现出强的区城选择性，甲苯硝化产物o/p值（甲苯硝化产物邻位和对位异构体的质量比）达0.89，较硝硫混酸的1.67显著降低，产物收率达到91.6%。

The measurement of apparent volume change is described during cure reaction of a new spiro ortho -carbonate, 3, 9, di (p-methooxybenzyl)- 1, 5, 7, 11-tetraoxspiro (5,5) undecaneand epoxy resin, and the volume expansion ratio of this new monomer is culcu-lated,and its applications are approached.

叙述了新的螺环化合物3，9-二-1，5，7，11-四氧杂螺环[5，5]十一烷与环氧树脂进行固化反应时，其表现体积变化率的侧定方法，推算了这种新单体的体积膨胀率。

The arylation showed high regioselectivity and only occurred on the less sterically hinderd ortho-C—H bond. The reaction could be compatible to diverse functional groups such as CH3, CH3O, and CH3CO, as well as Br and Cl substituents, which would permit to be functionalized further to construct new compounds with more complicated structures.

实验结果表明，反应表现出明显的区域选择性，芳基化只发生在空间位阻较小的sp2 C—H键上，反应可以采用多种取代基(如CH3O， CH3CO， Br和Cl)进行，这有助于通过进一步反应构建更为复杂的新化合物。

The production technology of triethyl ortho - formate as medicine intermediate is reviewed.

综述了医药中间体原甲酸三乙酯的生产工艺，重点介绍了二步法、一步法、氢氰酸法、酯交换法和相转移催化法的合成原理与生产工艺，并对这几种生产工艺进行了评述。

The first part of this study is focused on the synthesis and electro-optical properties and of poly(2,3-diphenyl-1,4-phenylene vinylene) containing polyethylene oxide side chains. The formation meso-structure nanocomposites by sol-gel process with tetraethyl ortho-silicate was demonstrated .

第一部份为聚-(2，3-双苯基-1，4-仲苯基乙烯)侧链接上聚环氧乙烷之合成、光电性质研究及透过溶胶-凝胶制程研究其自组装之奈米复合材料。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。