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41.
Combined gas chromatography-electroantennogram (GC-EAG) recording ofCampoletis sonorensis (Cameron) responses to cotton plant volatile chemicals was performed.C. sonorensis antennal olfactory receptors respond differentially to green leaf, mono-, and sesquiterpene chemicals that have been identified previously in cotton. EAG depolarizations to green leaf chemicals were greater than to terpenes. 相似文献
42.
Lucian M. Rusnac Octavian Floarea Radu V. Vladea 《Journal of the American Oil Chemists' Society》1992,69(4):384-386
Continuous hydrogenation of industrially refined soybean oil with Harshaw Ni catalyst was achieved in a slurry column equipped
with Sulzer SMV motionless mixers. The influence of the operating parameters (temperature, pressure, catalyst concentration
and gas velocity) was investigated. The presumption that, in this equipment, the liquid-solid mass transfer limits the rate
of the process is in good agreement with the experimental data. 相似文献
43.
湿法磷酸生产中,均以水为介质冲洗倾覆盘式真空过滤机的滤盘,为实现系统的污水零排放,提高倾覆盘式真空过滤机的生产能力,提出以回磷酸和硫酸配制成混酸去冲洗滤盘的方法。分析了采用该方法的诸多优点及注意事项,指出安全生产问题须认真落实。 相似文献
44.
Free primary alcohols in oils and waxes from germs,kernels and other components of nuts,seeds, fruits and cereals 总被引:2,自引:0,他引:2
Kazuko Kawanishi Kumlko Aoki Yohei Hashimoto Akira Matsunobu 《Journal of the American Oil Chemists' Society》1991,68(11):869-872
The composition of free primary alcohols in oils and waxes obtained from the germ, kernel, seed coat, shell and skin (peel)
of various nuts, seeds, fruits and cereals and from the chrysalis of silkworm was examined. These alcohols are usually present
in small amounts, along with large quantities of hydrocarbons, esters and glycerides in oils and waxes. Thus, it is necessary
to remove hydrocarbons, esters and glycerides to analyze the alcohols. We found that preparative reverse-phase thin-layer
chromatography (TLC) was the best way to isolate alcohols from oils and waxes. Gas liquid chromatography (GLC) then detected
hexacosanol, octacosanol and triacontanol in the oils and waxes. Octacosanol usually was the predominant alcohol. Relationships
between the organs from nuts, seeds, fruits and cereals and the contents of octacosanol are suggested. For example, degermed
kernels contained two times more octacosanol than the germ, and the skin coat and shell contained one-half and one-fortieth
the octacosanol of the germ, respectively. 相似文献
45.
废餐饮油制备生物柴油研究现状与应用前景 总被引:5,自引:0,他引:5
介绍了利用废餐饮油制备生物柴油的研究现状与应用前景;叙述了酸催化、碱催化和酶催化的酯交换制备生物柴油工艺,以及每种工艺的优缺点.阐述了我国利用餐饮废油制取生物柴油的意义和利用餐饮废油制取生物柴油的商业化生产的可行性. 相似文献
46.
为有效控制卷烟贮叶时间,保障制丝线产品内在质量,通过WinCC开发平台,设计贮叶时间动态监控系统,集中显示各贮柜当前状态,自动计算贮存时间,对超时贮存发出报警提示.系统能够为批次化的生产调度提供科学的时间依据,避免贮叶时间不足或超时现象,有利于平衡物料温度和含水率,改善卷烟香气特性,同时减轻操作人员工作压力,实现贮叶控制的自动化、智能化. 相似文献
47.
采用离子交联法,以高纯竹叶碳苷黄酮制剂(碳苷总质量分数﹥90%,记为H-BLF)和芫根阴离子多糖(TP)为原料,通过ε-聚赖氨酸(ε-PL)的阳离子桥键合而成竹叶碳苷黄酮纳米混悬液(H-BLFnd),进一步在混悬液中添加8%(w/v)的γ-环糊精、经真空冷冻干燥得到纳米冻干粉(H-BLFnp),采用粒径分析、TEM、UV、FTIR、TG和DSC对其外观、性能、结构进行表征。结果表明: H-BLFnp外观为白色粉状,表面光洁平整,色泽均匀,平均粒径为(679±10.2)nm,分散系数为(0.349±0.004),包埋率为(92.39±0.34)%。 相似文献
48.
Craig A. Dorschel 《Journal of the American Oil Chemists' Society》2002,79(8):749-753
A study of processed peanut oil was undertaken to assess the utility of HPLC combined with tandem MS to obtain data easily
regarding the number of TAG of fats and oils and their FA composition. Mass chromatograms and spectra corresponding to only
TAG of a single M.W. were obtained for the full range of TAG in the sample. Analysis of the mass spectra allowed the identification
of more than 160 TAG in the sample by their FA composition. In addition, it was possible to estimate relative abundances of
the TAG and suggest the position of the FA on glycerol for a limited number of cases. This technique greatly simplifies the
task of assigning FA to coeluting TAG and facilitates identification of TAG present in trace quantities in mixtures, with
possible application in circumstances where such trace TAG could be significant markers. Results are quickly obtained without
extensive sample preparation or prefractionation of the sample. 相似文献
49.
FemaleMicroplitis croceipes wasps were tested in a wind tunnel for their ability to orient to various concentrations of eight different green leaf volatile
(GLV) substances [hexanal, (E)-2-hexenal, (E)-2-hexen-1-ol, (Z)-3-hexen-1-ol, (E)-2-hexenyl acetate, (Z)-3-hexenyl acetate, (Z)-3-hexenyl propionate, and (Z)-3-hexenyl butyrate]. Overall, the esters elicited the greatest percentage of successful orientation flights, the alcohols
elicited an intermediate response, and the aldehydes elicited a low response. The semilog dose-response curves were generally
hill-shaped with high responses at medium release rates and low responses at high or low release rates. For the aldehydes,
positive responses occurred at all GLV release rates between 0.01 and 100 nl/min. For some alcohols and esters, positive responses
occurred at release rates as low as 1 pl/min and as high as 1μl/min. These data show thatM. croceipes wasps are strongly attracted to GLVs and are capable of orienting to GLV concentrations that would occur in nature when a
caterpillar feeds on a green leaf. Hence, in nature, GLVs may be important clues, enablingM. croceipes to locate their hosts. 相似文献
50.
Alejandrina Campanella Miguel A. Baltans 《European Journal of Lipid Science and Technology》2004,106(8):524-530
Vegetable oil epoxides (oxiranes) are customarily manufactured using acetic acid (AA) as oxygen carrier and reactant source, in aqueous/organic media. Further attack of the oxirane ring by AA proceeds in this acid‐catalyzed process, lowering yield. We report a study of the degradation of the ring by water‐solvated AA, using Amberlite IR‐120 as heterogeneous catalyst. The ring opening with solvated AA was found to be first order with respect to the concentration of epoxide groups and second order with respect to the carboxylic acid, with an activation energy of 58.7 ± 0.42 kJ mol?1. This value is within the range found in liquid‐liquid systems (51.3–66.3 kJ mol?1). Yet, using IR‐120, the degradation increases identically either by adding more mass of catalyst or by reducing its particle diameter while keeping the total mass constant, as both situations lead to higher external (exposed) area of the acidic catalyst (i.e., free protons associated to the sulfonic group) on the outer surface of the ion exchange resin beads. These free protons, in turn, become available to catalyze the attack on the oxirane groups of the long‐chain fatty acids, which cannot enter (diffuse) into the gel phase of the resin. Despite the unavoidable presence of surface‐exposed protons, the degradation can be reduced by several orders of magnitude – for similar process conditions – by using this type of heterogeneous catalysts instead of mineral acids. 相似文献