查询词典 para-phthalic acid

It is shown that mixed tolyl arsonic acid was much superior to either para- or ortho-isomer alone for cassiterite flotation.

当混合比为45：55时，锡石产率出现&峰值&，可得到较高的浮选指标。

A salt of bromic acid.A white, odorless, tasteless crystalline ester, ethyl-para-aminobenzoate(C6H4NH2CO2C2H5), used as a local anesthetic.

苯坐卡因，对氨基苯酸乙酯一种白色、无嗅、无味的晶体酯，对位氨基苯甲酸乙酯，（c6h4nh2co2c2h5），用作局部麻醉剂

The optimum reaction conditions were: at present of acetic anhydride, a stoichiometric quantity of nitric acid, at room temperature for 40 minutes. Nitration of chlorobenzene gave a,50% yield of mononitro compounds, and an ortho-para isomer ratio 0.20 in product distribution of chlorobenzene mononitration.

结果表明：硅钨酸催化性能较好，催化剂载体以纳米二氧化硅最好，反应条件中醋酸酐用量是主要影响因素；SiW_(12)O_(40)~(4-)／纳米SiO_2催化剂具有强对位选择性：在醋酸酐存在下，氯苯与等当量的硝酸室温下反应40分钟，氯苯一硝化产物中邻／对硝基氯苯异构体的质量比达0.2，产率可达50％。

And the ability of antioxidant of polyhydroxy benzamides don't have too many differences with Trolox (IC50 =13.90 μg/ml), the substition of hydroxy group at amino benzene ring doesn't affect the whole ability of antioxidant apparently, but while the single hydroxy group at carboxylic acid benzene ring, they are apparently decrease to scavenge the ability of free radical, as a result, the hydroxy at amino benzene ring substitutes its function, without the hydroxy group, the ability of antioxidant is worst, but it upgrades its function while the hydroxy and amino are in the ortho-position or para-position.

而当多酚醯胺化合物其抗氧化能力与Trolox差不多时(IC50 =13.90 μg/ml)，胺基苯环上之羟基取代对整体抗氧化能力影响不明显，但在羧酸苯环上具单羟基时，其清除自由基能力明显下降，使得胺基苯环上羟基取代发挥了影响力，无羟基取代时，抗氧化能力最差，而羟基与胺基互为邻位或是对位时较间位有提升效果。

Four chalcones were synthesized by aldol condensation reaction of acetophenone or para-substituted acetophenones with 2-phenyl-1,2,3-triazol-4-carboxaldehyde, which reacted with three hydrazines in glacial acetic acid under refluxing to give a series of pyrazoline derivatives.

以2-苯基－1，2，3-三唑基－4-甲醛为原料，与苯乙酮［或取代苯乙酮(1a~1d)］发生羟醛缩合，生成相应的查尔酮(2a~2d)，再与不同的肼反应，合成了12种新的5位含2-苯基－1，2，3-三唑基的吡唑啉衍生物3a~3d，4a~4d，5a~5d。

The polycondensation of the benzoguanamine and pyromellitic Dianhydride was carried out under microwave irradiation, and the resulted polyamic acid was grafted with TDI-para position substitution aniline derivatives. Thus graft polymers with different electronic effect of the end group in side chain were obtained.

将微波辐射合成的苯代三聚氰胺-均苯四酸二酐体系的PAA与TDI-对位取代苯胺衍生物反应，通过改变TDI－对位取代苯胺衍生物的对位取代基来合成具有不同电子效应的侧链端基的接枝聚合物。

The osteogenic differentiation markers were determined by para position Nitrobenzene phosphoric acid and Alizarin Red S staining.The expressions of CBFA1 and VEGF mRNA in BMSCs were detected by RT-PCR.

采用改良MTT法测定含药血清对P2代BMSCs增殖的影响；用对硝基苯磷酸法和茜素红S染色定量法对BMSCs分化为成骨细胞的标志物进行测定。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。