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The invention relates to a process for producing polyethylene terephthalate 1, 3-propanediol, which comprises the following steps: using titanic acid ester as major catalyst, using germanium compounds and cobalt compounds as synergic catalyst, conducting esterification reaction for poly terephthalic acid and 1, 3-propanediol according to the molar 1:1.05-2.2 under the nitrogen pressure of 0.1-0.4MPa and 230-265 DEG C, or conducting ester exchanging reaction for poly terephthalic acid and 1, 3-propanediol according to the molar ratio 1:1.8-2.2 in 160-220 DEG C, decompressing reaction to high vacuum 10-150Pa, wherein the final temperature of reaction is 265-275 DEG C, recovering to normal pressure with nitrogen to obtain the PTT product.

本发明涉及一种生产聚对苯二甲酸1，3-丙二醇酯的方法，采用以钛酸酯为主催化剂，锗化合物和钴化合物为协同催化剂，对苯二甲酸二甲酯和1，3-丙二醇按摩尔1∶1.05-2.2，在0.1-0.4MPa氮气压力和230-265℃下进行酯化反应，或对苯二甲酸二甲酯和1，3-丙二醇按摩尔比1∶1.8-2.2，在160-220℃进行酯交换反应，将反应减压至高真空10-150Pa，反应终温在265-275℃，用氮气恢复到常压，得到本PTT产品；大大缩短了反应时间，直接聚合制备特性粘度在0.7-1.05dL/g的PTT切片，使反应产物色相良好，PTT产品可用于纤维加工及工程塑料领域。

The invention relates to a preparation process for synthesizing polyethylene terephthalate 1, 3- terephthalate catalyst, which comprises adding titanic acid ester, germanium compounds and cobalt compound into liquid dispersed phase of organic solution, wherein the total weight concentration is 4-10%, and preparing the catalyst through mechanical stirring or ultrasonic wave mixed ligand for 10-60 minutes in 0-120 DEG C, wherein the adding content of titanic acid ester, germanium compounds and cobalt compound are respectively 200-500ppm, 50-300ppm and 100-400ppm of reaction monomer mass of terephthalic acid or dimethyl terephthalate.

本发明涉及一种合成聚对苯二甲酸1，3-丙二醇酯催化剂的制备方法，将钛酸酯、锗化合物和钴化合物加入到有机溶剂的液体分散相中，总重量浓度为4～10％，在0-120℃通过机械搅拌或超声波混配10-60min制得；钛酸酯、锗化合物和钴化合物加入量分别是对苯二甲酸或对苯二甲酸二甲酯反应单体质量的200-500ppm、50-300ppm、100-400ppm；用此催化剂制备PTT产品，酯化和缩聚反应时间相对于单独使用钛酸四丁酯缩短了30-60min，产品特性粘数0.70-1.05dL/g，色相b值在2-6之间，切片可用于加工新型合成纤维及工程塑料产品。

We at last got six compounds of Schiff Bases of triazole derivaties and five compounds of 1,3,4-oxadiazole.

由于酰肼便宜易得，因此我们选取了两种酰肼通过几种不同的方法合成了五种唑类化合物并以其中三种化合物为基础对其进行修饰，得到了六种含三氮唑取代基的席夫碱和五种1，3，4-噁二唑类衍生物。

Two compounds were synthesized with two methods. The two compounds can be synthesized by two steps with triethylamine as catalyst.

分别用氢氧化钠、三乙胺为缚酸剂，3-氨基-2-丁醇、2-氨基-3-戊醇、环己酮和二氯乙酰氯为原料，采用一步法和分步法合成了两种潜在除草剂安全剂。

Accord- ing to the observation that the compounds were stable in low pH aqueous solution and their sta- bility decreased when pH increased, and they rapidly decomposed to form α-methylenecyclopen- tanones derivative when pH reached 6 to 7, we postulated that the compounds were unabsorbable in stomack (where pH1-3) and unstable in small intestine (where pH5-8). The decomposed product was indeed inactive.

对Ⅰ类化合物在稀溶液中的稳定性研究表明，低pH时化合物较稳定，随着pH值的升高稳定性逐渐降低，pH6~7时，化合物迅速分解成α-亚甲基环戊酮类化合物，由此而推测Ⅰ类化合物经口给药无效的原因为：它们在强酸性的胃中（pH1-3）呈离子状态，因而不易吸收，经胃的排空运动进入肠道后，随着pH逐渐升高（pH5-8）化合物迅速分解，而分解产物α-亚甲基环戊酮类化合物证明是无效的。

Its beneficial widespread effect on health is attributed to sulphur compounds and particularly to thiosulfinates. Odorless and stable, alliin is the most abundant sulfur compound in whole, unbruised Garlic. When the clove of garlic is cut or crushed, the enzyme alliinase is released from its compartment and transforms S-allyl-L-cysteine sulfoxide or alliin into diallyl thiosulfinate allicin, the characteristic compound of garlic flavor. This very unstable thiosulfinate is rapidly degraded to related organosulfur compounds. Allicin is often thought of as the "active ingredient" in Garlic, and has been the subject of numerous scientific studies, but its a fairly unstable compound that likes to react with itself.

蒜氨酸(S-烯丙基-L-半胱氨酸亚砜，alliin)是完整、未受损大蒜里面含量最丰富的硫化物，并且非常稳定，它存在于大蒜的细胞质里；当细胞受损时，蒜氨酸酶从细胞液向细胞质释放，蒜氨酸和蒜氨酸酶接触被迅速转化为一系列新的化合物—蒜辣素及其相似物，蒜辣素(双烯丙基硫代亚磺酸酯，allicin)被认为是大蒜中最重要的活性成分，但它相当不稳定，易于自身反应。

As a rule, researchers discover that left-hand compounds are important medications, and left-hand compounds are useless, so much as unhealthful.

人们通常发现某些左手的化合物是有用的药物，而右手的异构体却没有期望的药效。

Thiocarbonyl compounds have similar chemical properties to those of carbonyl compounds because of their similar valence electron structures.

硫代羰基化合物与羰基化合物具有相似的价电子结构，因而具有类似的化学性质。

Analytical results showed that the upper clear liquid of pyrolysis oils was mainly consisted of water-soluble substances,such as phenol,cresol,xylenol,sugars,hydantoins,morpholines,pyranones and pyridine derivatives compounds,etc.,while the lower sediment was mainly insoluble or hardly water-soluble substances,such as the big substituent phenolics(the number of substituent carbon atoms of which is greater than or equal to 2),aryl phosphate esters,fatty acid esters and nitrile compounds,and so on.

研究表明，热解油上层清液主要是一些较易溶于水的物质，如苯酚、甲酚、二甲酚、糖类、乙内酰脲类、吗啉类、吡喃酮类和吡啶类化合物等；而下层沉淀则主要为不溶或难溶于水的物质，如大取代基酚类（取代基碳原子数≥2）、磷酸三芳基酯类、脂肪酸酯类和腈类化合物等。

Seven compounds have been isolated from hard coral Acropora pulchra. These compounds are:pentadecoic acid, heptadecyl ester;(2)n-cetanol;(3)batyl alcohol;(4) N- [ 1 --2-hydroxyl--3,7-heptad-ecadienal] -hexadecanamide;(5)1 -0-hexanoyl-glycerol ester;(6)thymine;(7)uracil. Their structures were determined by IR, MS, HNMR, 13CNMR analysis.

从北海佳丽鹿角珊瑚Acropora pulchra乙醇提取液的乙酸乙酯部分分离出七个化合物，经IR、MS、~1HNMR、~(13)CNMR等波谱方法鉴定，其结构分别为：(1)十五酸十七酯，(2)正十六碳醇，(3)鲨肝醇，(4)N-1-羟基甲基-2-羟基—-3，7-十七碳二烯基十六酸酰胺，(5)1-正十六酸甘油酯，(6)胸腺嘧啶，(7)尿嘧啶。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。