二戊基

The results show that all the hmgr genes from pigs, cattle and chickens are astable enzyme proteins with the same gene sequence characteristics and encoding protein and physical and chemical properties; all the amino acid sequences have a high degree of homology, containing two conservative HMG-CoA binding motifs and two NADPH binding motifs; all the amino acid sequences, containing signal peptide, are secreted proteins; they are all hydrophobic transmembrane proteins with five transmembrane domains; random coil and α-helix are the main structural elements in the HMGR polypeptide chain; all the predictions of three-dimensional structure are V- shaped; there are more closer evolution relationship between the HMGR gene from pigs and cattle.

结果表明：猪、牛和鸡HMGR基因序列特点及编码蛋白质理化性质基本相同，均属不稳定类酶蛋白；保守结构域氨基酸序列具有高度的同源性，均含有保守的2个β-羟基-β-甲基戊二酸单酰辅酶A结合基序和2个还原性烟酰胺腺嘌呤二核苷酸结合基序；均有信号肽，属分泌型蛋白质；属于跨膜的疏水性蛋白，均有5个跨膜结构域；无规则卷曲和α-螺旋是HMGR多肽链中的主要结构元件；三维结构预测都呈"V"字形；猪和牛HMGR基因的进化关系最近。

Natural rubber which is cis 1,4 - polyisoprene is composed of isopentenyl pyrophosphate In Hevea brasiliensis.

巴西橡胶树中的天然橡胶是顺式-1，4-聚异戊二烯（cis-1，4-polyisoprene），其基本组成单元是异戊烯基焦磷酸(isopentenyl diphosphate ，IPP)。

Isoprene could be deeply hydrogenated to isopentane on nickel catalyst.

异戊二烯在镍基催化剂作用下可深度加氢为异戊烷。

We examined the effects and mechanisms of methyl pentyl 1,4-dihydro-2,6-dimethyl-4-(3-notrophenyl)-3,5-pyridinedicarboxylate (Mn9202), a novel DHPs calcium antagonist and lacidipine on the 5-HT2B receptor in cultured rat stomach fundus smooth muscle cells.

本研究以富含5-HT_(2B)受体的大鼠胃底平滑肌细胞为模板，观察了二氢吡啶类钙拮抗剂2，6-二甲基-4-（3-硝基苯基）-1，4-二氢-3，5-吡啶二羧酸-3-甲酯-5-正戊酯（Mn9202）、拉西地平对 5-HT_(2B)受体功能的影响，并对其影响机制进行了较为深入的研究。

Uncured natural rubber is sticky, easily deforms when warm, and is brittle when cold. In this state it cannot be used to make articles with a good level of elasticity .

一般需经过硫化的橡胶品种有丁二烯、氯丁二烯、异戊二烯的1，4-聚合物--顺丁、异戊、氯丁橡胶，以及共聚物丁苯、丁基和丁腈橡胶等。

The optimal carrier gas velocity of prepared SE-30 series capillary chromatographic columns was studied and used to separate isomeric compounds. The efficiency of SE-30 capillary chromatographic columns has been studied with different diameters, film thicknesses and oven temperatures, using n-do-decane, phenol, aminobenzene, and butyl acetate as test samples.

研究自制的SE-30系列毛细管气相色谱柱的载气最佳线速度，并应用于同分异构体的色谱分离分别用十二烷、苯酚、苯胺、醋酸丁酯作试祥在不同载气线速条件下对不同口径、不同膜厚、不同柱温的SE-30毛细管色谱柱的柱效进行考察，并在最佳线速度条件下分离异戊醇、硝基氯苯、硝基甲苯及二乙苯同分异构体体系。

Under the optimum conditions of a cyclopentene amount of 1.0 mol, a molar ratio of cyclopentene to water of 0.25, a reaction temperature of 120 ℃, a reaction time of 4.0 h, a main catalyst dosage of 4.0 g and a cocatalyst dosage of 0.8 g, the yield of cyclopentanol reached 68.6%.

确定适宜的反应条件为：环戊烯1.0 mol，n﹕n=1﹕4，反应温度120 ℃，反应时间4.0 h，硅胶负载铌酸主催化剂用量4.0 g，三（3，6-二氧杂庚基）胺助催化剂0.8 g。在此反应条件下，环戊醇收率68.6%。

Trifluoromethyl-3-heptadfluoroisopropyl-2-perfluoropentene-4-(N',N'-dimethylamino propyl) imino was prepared by the reaction of hexafluoropropene timer with N,N-dimethyl propanediamine in the molar ratio 1:1.0 at room temperature for 8h, and the structures of VIII were identified by IR and NMR spectra.

以六氟丙烯三聚体与N，N-二甲基丙二胺为原料合成叔胺2-三氟甲基-3-七氟异丙基-2-全氟戊烯-4-(N'，N'-二甲胺丙基)亚胺，利用红外光谱和核磁共振确定其结构，并通过对合成条件的考察得其最佳合成条件：乙醚为溶剂，碳酸钠为缚酸剂，摩尔投料比为1：1.0，在室温下反应8小时。

The α-monobromination of 2-pentone,4-methyl acetophenone,4-methoxyacetophenone,6-methoxy-2-acetylnaphthane,2,2,5,5-tetramethyl-3-hexanone,cyclooctanone,cyclododecanone with respectively,were studied.

研究了离子液体三溴化1-丁基-3-甲基咪唑[Br3]对2-戊酮、4-甲基苯乙酮、4-甲氧基苯乙酮、6-甲氧基-2-乙酰基萘、2，2，5，5-4-甲基-3-己酮、环辛酮、环十二酮、丁醛等羰基化合物的α-溴化反应。

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。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。