查询词典 isobutyl

In this work, isobutyl isobutyrate was prepared by the condensation of two molecular isobutyraldehyde in the presence of aluminium isobutoxide catalyst system.

依据间歇反应所得一系列数据，确定了异丁醛连续缩合反应工艺流程；考察了以异丁醛为原料，在 5～10℃，停留时间 1 5～ 2h ，在异丁氧基铝催化体系作用下，两分子异丁醛缩合成一分子异丁酸异丁酯；脱除催化剂后，粗产品精制得到纯度≥ 99 5 %的异丁酸异丁酯，异丁醛的转化率≥ 98 5 %，异丁酸异丁酯的选择性≥95 %。

Several routes for synthesizing methyl isopropyl ketone were introduced, including the main methods based on isobutyl aldehyde-acetic acid, isobutyric acid -acetic acid, methyl ethyl ketone-formaldehyde and isoprene.

介绍了甲基异丙酮的多种合成路线，主要有异丁醛-乙酸法、异丁酸-乙酸法、甲基乙基酮-甲醛法和异戊二烯法。

Gated ~(99)Tc~m-hexakis-2-methoxy-isobutyl isonitrile /~(18)F-fluorodeoxyglucose single photon emission tomography with dual isotope simultaneous acquisition can provide the information about left ventricular function, myocardial perfusion and metabolism simultaneously.

~(99)Tc~m-甲氧基异丁基异腈和~(18)F-脱氧葡萄糖双核素同时采集单光子计算机断层显像可以一次显像获得左心室心肌的血流灌注和葡萄糖代谢的情况，如果加上门控采集，可以同时了解左心室功能的信息。

ABSTRACT Gated 〓Tc〓-hexakis-2-methoxy-isobutyl isonitrile /〓F-fluorodeoxyglucose single photon emission tomography with dual isotope simultaneous acquisition can provide the information about left ventricular function, myocardial perfusion and metabolism simultaneously.

Tc〓-甲氧基异丁基异腈和〓F-脱氧葡萄糖双核素同时采集单光子计算机断层显像可以一次显像获得左心室心肌的血流灌注和葡萄糖代谢的情况，如果加上门控采集，可以同时了解左心室功能的信息。

Bone marrow mesenchymal stem cells could differentiate into osteoblasts, adipocytes and neural like cells with osteoblast inductor (β-sodium glycerophosphate, dexamethasone, vitamin C), lipoblast inductor (dexamethasone, 3-isobutyl-1-methylxanthine, bovine insulin, indometacin) and serum-free medium inductor (dimethyl sulphoxide, butylated hydroxyanisole) respectively. Osteoblast marker (alkaline phosphatase, osteocalcin mRNA, calcium node), adipocyte marker (lipid droplet, PPAR γ-2mRNA) and neural cell-like marker (nissl body, neuron specific enolase, neurofilament protein) were respectively determined by the immunohistochemical method, polymerase chain reaction and immunocytochemical method.

分别采用成骨细胞诱导剂（β-甘油磷酸钠，地塞米松，维生素C）、成脂肪细胞诱导液（地塞米松，甲基异丁酸黄嘌呤，牛胰岛素，吲哚美辛）及二甲基亚砜和羟基丁酸苯甲醚无血清培养基诱导剂干预细胞向成骨、脂肪、神经细胞分化，经免疫组织化学染色、PCR、免疫细胞染色方法检测成骨标志物（碱性磷酸酶、骨钙素mRNA、钙结节）、脂肪标志物（脂滴、PPARγ-2mRNA）、以及类神经标志物（尼克氏体、神经烯醇化酶、神经丝蛋白）。

Ascorbic acid, ammoniun rhodanate and methyl isobutyl ketone are used to extract Mo form soil sample solution for the purpose of removing matrix interferences.

研完了水相酸度，各试剂用量，不同有机溶剂以及共存干扰离子对萃取和测定的影响，无须去掉水相直接测定有机相中的钼。

Results The mixing, loading and storing processes of the construction, might generate lots of occupational hazards, including toluene, dimethylbenzene, trimethylbenzene, isopropanol, butyl alcohol, propanol, methyl methacrylate, butyl acetate, methyl isobutyl ketone, methyl ethyl ketone, acetic ether, nitro-cotton, n-hexane, n-heptane, carbinol, ethanol, ethyl propionate, diisobutyl ketone, glycol ether, isoamyl acetate, 2,4-toluene diisocyanate, isophorone, noise, power frequency electric fields.

结果 该项目在混兑生产和装卸、仓储过程中，可能产生的职业病危害因素主要有甲苯、二甲苯、三甲苯、异丙醇、丁醇、丙醇、甲基丙烯酸甲酯、乙酸丁酯、甲基异丁基甲酮、丁酮、乙酸乙酯、硝化棉、正己烷、正庚烷、甲醇、乙醇、乙酸丙酯、二异丁基甲酮、乙二醇乙醚、乙酸异戊酯、2，4甲苯二异氰酸酯、异佛尔酮、噪声、工频电场。

D-Pantothenyl alcohol, also called ortho-vitamin 85, is an important nutrition suppled substance. It has been widely applied in the field such as medicine, cosmetic, foodstuff, feed additive, and so on. The preparation of D-pantothenyl alcohol and the optimization of key factor are discussed mainly in this paper. It mainly includes three section.In the first section, with formaldehyde, isobutyl aldehyde and diethyl oxalate as the starting materials, D-pantolactone is prepared via three steps including condensation, catalytic hydrogenation and physical resolution. The specific rotatory power of the product is consistent with imported product.

D-泛醇，俗称原维生素B_5，属维生素B旋类营养增补剂，广泛应用于医药、化妆品、食品、饲料等领域，本文着重探讨了其制备及关键因素的优化，主要内容可分三部分：第一是D-泛内酯的制备，先以甲醛、异丁醛和草酸二乙酯为起始原料合成酮基泛内酯，再经催化氢化得到DL-泛内酯，然后通过物理拆分获得D-泛内酯，得到产物的比旋光度与进口产品基本一致。

Firstly, headspace solid-phase microextraction was established to determine AITC by orthogonal design. Extraction temperature, stir speed, extraction time, and desorption time were set at 40℃, 900r/min, 30min, and 5min, respectively. Under these optimal conditions, volatile flavor compounds in mustard oil, wasabi, and 'Chongcai'leaf mustard product were identified by SPME/GC/MS. In these three samples, 6,12,17 constituents were identified respectively; Allyl isothiocyanate was the main flavor compound, which accounted for 73.45%, 64.25%, 32.74% of total volatile compounds, respectively. Carbon disulfide, a hydrolysis product of AITC, accounted for 14.37% 25.40%, 51.67% of total volatile compounds respectively. There were some other isothiocycannates, such as butane, 1-isothiocyanato-, isobutyl isothiocyanate, 1-benzene, 4-isothiocyanato-, benzene (2-isothiocyanatoethyl)-, etc.

首先采用正交实验设计优化固相微萃取技术的前处理条件，结果表明，以萃取温度40℃、搅拌速度900r／min、萃取时间30min、解吸时间5min为最佳条件；在此最优条件基础上，利用SPME／GC／MS联用技术分析芥末油、青芥辣、冲菜的挥发性风味成分，分别检出6、12、17种化合物，主要风味物质均为AITC，相对丰度分别为73.45％、64.25％、32.74％；AITC的水解产物二硫化碳的相对丰度分别为14.37％、25.40％、51.67％；还检测到了其它几种异硫氰酸酯，如异硫氰酸丁酯、异硫氰酸异丁酯、异硫氰酸丁烯酯、2-苯乙基异硫氰酸酯等。

At the same time, with reference to the conditions of synthesis of methyl ester of salicylic acid, we combined ethyl ester of salicylic acid, salicylic acid-n-butyl, isobutyl salicylate, amyl salicylate, isoamyl salicylate and salicylic acid benzyl ester,besides, experimented the possibility for series of ester synthesis catalyst with Sodium bisulfate as a catalyst .

同时参照水杨酸甲酯的合成条件合成了水杨酸乙酯、水杨酸丁酯、水杨酸异丁酯、水杨酸戊酯、水杨酸异戊酯和水杨酸苄酯，实验了以硫酸氢钠为催化剂合成系列酯的可能性。

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。