石油醚

According to explore the extracting process of coumarin from melilotus, include extracting with ethanol, decoloring with petroleum ether and extracting with chloroform was determined.

通过对提取工艺进行探索后，确定了乙醇提取、石油醚脱色、氯仿萃取的工艺路线。

Results show the optimal conditions for the moringa seed oil extraction are as follows: using petroleum ether as solvent,the ratio of solvent to moringa seeds is 8∶1,extraction time 40 min and extracting twice with the aid of 28 kHz ultrasonic.At the conditions,the ...

结果显示，超声波辅助溶剂萃取辣木籽油的最佳条件为：溶剂石油醚，提取次数2次，提取时间40 min，超声波频率28 kHz，液料比8∶1，在此条件下，辣木籽的平均出油率为35.85%，提取率96%，表明超声波辅助溶剂萃取法是一种可用于萃取辣木籽油的适宜方法。

When catalyst (sherwood oile was used to dissolve stannous octoate and get liquor which concentration was 0.00001 mol/ml) was 1ml, temperature was 165℃, time was 5h, the percentage yield of PGLA was 79.5%.

合成共聚物采用的催化剂为用石油醚溶解的浓度为0.00001mol/ml的辛酸亚锡溶液，当催化剂用量为1ml，温度为165℃，时间为5h时，产率达到最大值，为79.5

It achieves a certain extent effect of waterproof and oilproof. 3. Test the change of surface ingredient before and after the fluoridized of the FRP usingthe reflecting method of infrared spectrum. Then dip the fluoridized FRP in the cold water, warm water and petroleum ether for about half an hour, and surface ingredient havent changed too much.

用红外光谱反射法测试了经含氟物处理前后的玻璃钢表面结构变化，并且分别测试了在冷水、温水、石油醚中浸泡洗涤半个小时后的表面含氟处理的玻璃钢的表面结构，发现其表面结构与浸泡前无大的变化。

The parasiticidal effect of ethanol extracts from a plant Dioscorea zingiberensis on dactylogyrid Dactylogyrus intermedius found in goldfish was studied to search for parasiticidal substances by standard laboratory procedures compared with the other four drugs mebendazole, abamectin, ivermectin and praziquantel.

以寄生在金鱼Carassius auratus鳃部的中型指环虫Dactylogyrus intermedius为指示寄生虫，采用活体感染、活体杀虫的方法，研究了用不同溶剂（石油醚（沸程60~90℃）、氯仿、乙酸乙酯、乙醇和水）分别对盾叶薯蓣Dioscorea zingiberensis进行提取，其5种提取物的杀虫活性。

Two compounds have been isolated from hard coral Porites Compressa Dana,their structures were determined by IR,MS, HNMR, 13CNMR analysis.The two compounds are: batyl alcohol,(2) N-[l--2-hydroxyl--3,7-heptadecadienal]- h exadecanamide.

从采自西沙群岛的扁缩滨珊瑚中的石油醚部分分离出两个化合物，经IR、MS、~1HNMR、~(13)CNMR等波谱方法鉴定，其结构分别为(1)鲨肝醇，(2)N-1-羟基甲基-2-羟基--3，7-十七碳二烯基十六酸酰胺。

Results By using two-phase solvent systems composed of petroleum ether-ethylacetate-methanol-water (22:25:23:17) at the flow rate of 2.0 mL/min, with rotating speed of 800 r/min, and at temperature of 25℃, the yield of d1-tetrahydropalmatine and of protopine purified from the total alkaloids being 16.9% and 14.7%, with purity of 99.3% and 98.8% respectively can be reached.

结果 石油醚－乙酸乙酯－甲醇－水(22：25：23：17)为溶剂体系，流速为2.0 mL/min，仪器转速800 r/min，温度25℃，从延胡索总碱中可一步纯化得到原阿片碱和延胡索乙素，得率分别为16.9%和14.7%，纯度分别为99.3%和98.8%。

Then recrystallize the thick product with the petroleum ether, the end product obtains its melting point after infrared lamp drying with the melting point detector and compares with the pure Diphenyl carbinol.

粗产物用石油醚重结晶，终产品经红外灯烘干后用熔点测定仪得到其熔点，并与纯品二苯甲醇比较。

The insecticidal activities of the ethanol extracts and 5 kinds of extracts with petroleum ether, chloroform, ethyl acetate, n-butanol, aqueous from Rubia cordifolia L. against wolfberry aphis was investigated.

采用点滴法，测定了茜草乙醇提取物和石油醚、氯仿、乙酸乙酯、正丁醇和水5种不同极性萃取物对枸杞蚜虫的触杀活性。

Additionally, 75 volatile chemical constituents have been identified from the petroleum ether extracted part by capillary GC-MS, and the relative percentages of them are determined by GC method. The result showed that the volatile constituents of Musella lasiocarpa mainly includes advanced alkane, aliphatic acid and ester, aldehyde, ketone, aromatic and its heterocyclic compounds. With the compounds that have been isolated and identified from Musella lasiocarpa, the biogenensis pathway of new compound MT-3 is approached. Furthermore, the bacteriostasis of the 6 compounds to Escherichia coil, Pseudomonas aerusinosa, Bacillus megaterium, Sarcina lutea and Bacillus subtilic are determined by flat dilution method.

此外，从其石油醚萃取部分用毛细管色谱法分析鉴定出75种挥发性化学成分，并测定了各组分的相对百分含量，结果表明，地涌金莲挥发性化学成分以高级烷烃、高级脂肪酸酯及醛、酮、芳香和芳香杂环化合物为主；根据从地涌金莲中鉴出和分离得到的化合物，探讨了新结构化合物MT-3的生源代谢途径；采用平板稀释法测定了地涌金莲中六种化学成分对大肠杆菌、绿脓杆菌、巨大芽孢杆菌、藤黄八叠球菌和枯草芽孢杆菌的抑菌作用。

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。