查询词典 para-phthalic acid

A process for reducing nitryl with unstable guanyl on para-position of benzene ring into azyl features that active metal reacts on organic acid and solvent at ordinary temp. and pressure to reduce N-(2 or 3-M, 5 or 6-M',4-nitrophenyl)-N',N'-dimethyl acetamidine into N-(2 or 3-m, 5 or 6-M', 4-aminophenyl)-N',N'-dimethyl acetamidine, where M=H,-R,-OR,-COOR (R=H, C1-C6); and M'=H,-R,-OR,-COOR (R=H, C1-C6). Its advantages include reduced by-reaction and high reducting rate up to 80%-95%.

本发明是将苯环上对位带有不稳定脒基的硝基还原为氨基的方法，采用活泼金属，如：锌或锡，与有机酸和适当的溶剂，在常温、常压下发生反应，将N－（2或3－M，5或6－M＇，4－硝基苯基）－N＇，N＇－二甲基乙脒还原为N－（2或3－M，5或6－M＇，4－氨基苯基）－N＇，N＇－二甲基乙脒，其中M＝H，－R，－OR，－COOR（R＝H，C1－C6），M＇＝H，－R，－OR，－COOR（R＝H，C1－C6），减少了副反应，使还原收率达到80％以上，最高可达95％以上，更适用于工业化生产。

In experimental research, the S-L-E of three groups of isomers was determined by using differential scanning calorimetry , and more than two hundred reliable data were obtained. The isomers include meta-, ortho-, and paradichlorobenzene, meta-, ortho-, and para-dibromobenzene and meta-, ortho-, and para-nitro-benzoic acid.

在实验的研究中，采用差式扫描量热测定了邻、间、对二氯苯，邻、间、对二溴苯及邻、间、对硝基苯甲酸等三组同分异构体物系的固液相平衡关系，共得到二百多个可靠的数据。

Chemical corporations within this region may provide matching chemical products and raw materials such as citric acid, starch sugar, L-lactic acid, nitrochlorobenzene, paranitrophenol sodium salt sodium para-nitro phenolate, pphenylenediamine , sodiumhydroxide, benzene anhydride, carbonic acid propylene grease, polyacrylamide ,2.4- dinitrochlorobenzene, 2.4- dinitrosixchlorin, and sodium cyanide.

区内化工企业可配套提供柠檬酸、淀粉糖、 L —乳酸、硝基氯苯、对硝基酚钠、对苯二胺、烧碱、苯酐、碳酸丙烯脂、聚丙烯酰胺、2.4—二硝基氯化苯、2.4—二硝基6氯、氰化钠等化工产品或原料。

The results showed that the amorphous iron oxide has highly catalytic activity. The intermediate products are pyrocatechin, hydroquinone, benzoquinone and low-grade fatty acid. The mechanism of catalyst oxidation is assumed that the free radical OH attacks benzene cycle at the adjacent position and para-position of OH on phenol so that the benzene cycle is opened and low-grade fatty acid is produced and transformed into CO2 and H2O.

结果表明，非晶铁氧化物催化剂在催化氧化降解苯酚时具有较高的催化活性，苯酚降解的中间产物有：对苯二酚、邻苯二酚、苯醌和低级脂肪酸，其降解机理是羟基自由基攻击苯环上OH的部位或对位而使苯环开环，生成低级脂肪酸，并最终转化成二氧化碳和水，从而使苯酚得以降解。

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。

This process utilizing modern efficient wire gauze wave-like packings sepa-rates three isomers of MNT(ortho-.meta- or para-), then the O-MNT or P-MNTis nitrated to produce military TNT by a mixture of nitric and sulfuric acid.

本工艺利用近代高效的金属丝网波纹填料分离MNT的三种异构体，然后用硝硫混酸把邻一或对一MNT硝化成军品TNT，这样可避免亚硫酸钠溶液精制TNT的工序。

A crystalline para form of aminobenzoic acid that is part of the vitamin B complex and is widely used in sunscreens to absorb ultraviolet light.

对氨基苯酸一种结晶的氨基苯酸形式，是维他命b复合物的一个组成部分并被广泛地用于过滤剂中以吸收紫外线光

Para'.'' form of aminobenzoic acid that is part of the vitamin B complex and is widely used in sunscreens to absorb ultraviolet light.

对氨基苯酸一种结晶的氨基苯酸形式，是维他命b复合物的一个组成部分并被广泛地用于过滤剂中以吸收紫外线光

OH radicals produced by ultrasound in aqueous solution attack phenolic cycle at adjacent or para position of the hydroxyl on phenol so that phenol is changed into small organic molecules such as muconic acid, maleic acid and ethane diacid. These small organic molecules will be oxidized to form carbon dioxide and water by.

苯酚超声降解的作用机理是，超声空化在水溶液中产生的·OH自由基进攻苯酚苯环上羟基的邻位或对位而使苯环断裂生成己二烯酸、顺式丁烯二酸和乙二酸小分子有机物而使苯酚得以降解，这些小分子有机物在·OH自由基的进一步作用下最终被氧化成CO〓和H〓O。

Folic acid is Vitamin Bc made up of 2-amino-4-hydroxyl-6-methylpterin, para-amino benzoic acid and glutamic acid, transforming into tetrahydro-folic acid in the human body, the ones that participated in formatting amino acid and nucleic acid.

中文摘要：叶酸系由2-氨基-4-羟基-6-甲基蝶呤、对氨基苯甲酸及谷氨酸组成的水溶性B 族维生素，在人体内转化成四氢叶酸，参与氨基酸及核酸的合成。

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。