醚

But due to the commonstructure characteristic of the segmented copolymers, the ratio of 〓 is still aneffective parameter to predict the crystallizability of the two segments in limitedenvironment.

虽然这个确切的比值对聚醚酯多嵌段共聚物不具有普遍意义，但是由于聚醚酯多嵌段共聚物共同的结构特征，软硬链段之间的相对长度仍是一个反映两种链段结晶能力的一个很有用的参数。

SMM is the main precursor substance of DMS, and Cystine is one of the precursor substances of DMS in vegetables.

硫甲基蛋氨酸是蔬菜中甲硫醚主要的前体物质，胱氨酸是蔬菜中甲硫醚的前体物质之一。

A total of one hundred fifty three healthy male and female adults were entered into a six month,doubleblind clinical study designed to evaluate the effect of a dentifrice containing 0.3% triclosan and 2.0% PVM/MA copolymer in a 0.243% sodium fluoride/silica base, relative to a 0.243% sodium fluoride silica base control dentifrice on supragingival plaque accumulation and gingivitis.

本研究的目的是证实含0.3％三氯羟苯醚，2.0％PVM／MA及0.243％氟化钠以二氧化硅磨料牙膏在减少菌斑积聚和牙龈炎形成方面对中国成年人群的效果。153名健康男女分为实验组及对照组，用双盲法评价6月后临床效果。采用纳入和排除的评价标准后进行了基线检查，实验对象每日使用分配的牙膏和软毛牙刷早晚刷牙一次，3个月和6个月再次检查。检查结果表明，使用含有三氯羟苯醚－共聚体牙膏组与使用不含该成分的对照组相比，实验对象的牙菌斑、牙龈炎指数分别减少16.1％及24.3％，均有统计学显著性意义（P＜0.001）。

Eleven novel 2-alkylthio-5-(5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine-5-yl)-1,3,4-oxadiazole derivatives (5) and six novel 2-alkylthio-5-(5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine-5-yl)-1,3,4-thia- diazole derivatives (8) have been designed and synthesized by using 5-amino-3-ethoxycarbonyl-1H-1,2,4-triazole as a starting material.

以5-氨基－1H-1，2，4-三唑－3-羧酸乙酯为起始原料，设计合成了11个新型的2-取代硫醚－5-（5，7-二甲基－1，2，4-三唑并[1，5-a]嘧啶基）-1，3，4-恶二唑类化合物(5)和6个新型的2-取代硫醚－5-（5，7-二甲基－1，2，4-三唑并[1，5-a]嘧啶基）-1，3，4-噻二唑类化合物(8)。

Benzoxazine compounds are one kind of highly active protoporhyrinogen oxidase inhibitors. These compounds can effectively control both monocotyledon weeds and dicotyledon weeds at lower dosage. The action mechanism is similar to p-nitro-o-substituted diphenylethers. They can result weeds albinism and decolorization, which are very important albinism herbicide.

苯并噁嗪类化合物是一类高活性的原卟啉原氧化酶抑制剂，低剂量可有效地防除禾本科与阔叶杂草，其作用机理和对硝基邻位取代的二苯醚类似，它们造成白化或脱色，是白化除草剂中较重要的种类，其活性远超过二苯醚除草剂，是目前化学农药研究领域的热点。

The complexes of disk - like crown ether liquid crystal with Eu have theproperties of liquid crystals and havn't the properties of fluorescence. The complexes of disk -like crown ether liquid crystal with Eu and β-diketone have the properties of fluorescence and electroluminescence.

盘状冠醚液晶Eu配合物具有液晶性质而无荧光特性；盘状冠醚液晶与EuⅢ）和β-二酮形成的配合物具有荧光特性，和电致发光性质。

Objective: To study the effects of pentabrominated diphenyl ethers on the structure and function of reproductive system in rats and mechanism.

目的：研究五溴联苯醚对大鼠生殖系统结构和功能的影响及其机制方法：在五溴联苯醚对雄性大鼠生殖系统作用的时效关系研究中，选取健康23日龄雄性SD大鼠40只，体重40～60g，随机分为8组，每组5只，分别为染毒5、15、30、45d的实验组和溶剂对照组。

Inconclusion, equipotent concentrations of desflurane or sevofluranein terms of BIS are associated with similar rSO2 values, butlarger anesthetic concentrations of both anesthetics increasedthe rSO2 values.

结论，在 BIS 方面等效浓度的地氟醚和七氟醚具有相似的 rSO2值，而两个麻醉药的较大麻醉剂浓度能提高 rSO2值。

Results: The extracts of ethanol, petroleum ether and ethyl acetate of Rhizoma Amorphophalli have inhibitory effect on the proliferation of cell SGC-7901, and the extract of petroleum ether has much more evident effect, showed a dose-effect curve.

结果：蛇六谷醇提取物、石油醚萃取物和乙酸乙酯萃取物均具有一定的抑制人胃癌SGC-7901细胞增殖的作用，以石油醚萃取物的抑制作用最为明显，呈现较好的剂量－效应曲线。

Some factors affecting the etherification, such as temperature, time and catalysts etc, were studied, and the relatively optimal reaction conditions were worked out molar ratio of reaction material/catalyst 1/1, T=100, t=1 h.

研究了影响醚化反应的一些因素，如温度、时间、催化剂等，并在此研究基础上得出了较佳的醚反应条件为：物料／催化剂的摩尔比为1/1，温度为100℃，时间为1 h。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。