查询词典 petroleum ether

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。

The optimal reaction parameters of methanolysis of soybean oil by lipase-catalysis weredetermined as follows: 15wt% of lipase, 55℃of temperature, petroleum ether as solution,methanol was added by 6 times.

对酶法催化豆油和地沟油的对比没有显著差异，说明脂肪酶是催化游离脂肪酸含量高的油脂生产生物柴油的有效催化剂。

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。

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。

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。

Take silica gel chromatography eluting with EtOAc / petroleum ether(1:9～5:5). The production was washed several times by MeOH, and dissolved in dimethyl formamide to recrystallize, we got yellow power crystal.

结果：(1)HPLC检测含量大于95％，符合对照品的要求；(2)理化鉴别实验均与文献吻合；(3)紫外、红外、质谱、核磁共振的光谱结果均与文献值一致，确定产物为金松双黄酮。

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 results show that the resulting product can be separated by the mixture of petroleum ether, aether and acetic acid (10:10:1, V/V). Among them, the oleic acid component can be eluted by the mixed solvent of ethanol and carbon tetrachloride (35:15, V/V), and then productivity of sodium oleoyl sarcosine can be obtained.

结果表明：用石油醚：无水乙醚：冰乙酸＝10：10：1分离产物中的组分，再用无水乙醇：四氯化碳＝35：15混合溶剂洗脱制备油酸组分，进而计算油酰肌氨酸钠的产率是可行的。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。