γ-松油烯型白千层油成分分析的研究

利用GC/MS联用及GC方法对γ-松油烯型白千层油进行了定性和定量分析,鉴定出其中23个组分,占挥发油总量的93.44%以上,主要成分为γ-松油烯（44.03%）、α-蒎烯（12.71%）、α-松油醇（9.65%）、1,8-桉叶素（7.98%）和4-松油醇（4.73%）,其中γ-松油烯和α-蒎烯含量高于其他类型的白千层油。     

不同产地肉豆蔻油中挥发性成分的GC-TOF/MS分析

采用气相色谱-飞行时间质谱法(GC-TOF/MS)分析不同产地肉豆蔻油的挥发性成分,并通过质谱库检索,结合保留指数比对,从英国、中国云南和印尼三个产地的肉豆蔻油中分别鉴定出69、78和67个挥发性成分,分别占总峰面积的99.74%、99.87%和99.65%。三个产地肉豆蔻油的挥发性成分在组成和含量上较为相似,三者的主要成分为肉豆蔻醚、α-蒎烯、桧烯、β-蒎烯、α-松油烯、4-松油醇、γ-松油烯、柠檬烯等化合物。     

孜然香气与精油成分比较研究

采用顶空固相微萃取一气相色谱一质谱法萃取和分析孜然粉末香气,共检测出19种成分,解析鉴定出占总挥发性成分99.695%的18种成分,主成分是两种蒈烯醛异构体(33.174%)、γ松油烯(17.858%)、枯茗醛(17.280%)、β蒎烯(13.940%)和对伞花烃(6.541%).以水蒸汽蒸馏法提取孜然,精油的得率为2.6%,用GC-MS联机对精油进行了成分分析,检测出28个成分,解析鉴定了占精油99.801%.4的26个成分.主要成分为枯茗醛(39.511%)和两种蒈烯醛异构体(35.249%),其次为γ松油烯(7.096%)、α-7-松油烯醇(5.315%)、β-蒎烯(5.242%)和对伞花烃(3.000%).     

互叶白千层精油GC—MS挥发性成分及抗茵活性研究

通过使用GC—MS联用技术对互叶白千层精油进行分析,从中鉴定了30种化学成分,占总含量的95．78％。主要成分松油烯醇-4,达到了45．81％;其次为1-松油烯,α-松油醇,α-松油烯,对伞花烃,α-蒎烯,1,8-桉叶油素,β-水芹烯。抗菌活性研究发现,互叶白干层精油对大肠杆菌、金黄色葡萄球菌以及白色念珠菌等具有一定的抗菌能力。     

黑龙江产万寿菊花精油的化学成分研究

采用水蒸汽蒸馏法提取黑龙江产盛花期的万寿菊花精油,精油产率为0.0943%。采用气相色谱-质谱(GC-MS)对精油的化学成分进行了定性定量分析,共分离出47个峰,鉴定出其中的40个化合物,占峰面积的85.11%。用面积归一化法测定了各种成分的相对质量分数,万寿菊花精油的主要成分为萜类化合物,主要成分有异松油烯(32.91%)、α-罗勒烯(11.18%)、柠檬烯(10.87%)、石竹烯(7.46%)、β-月桂烯(5.64%)、反-β-罗勒烯(5.34%)和2-异丙基-5-甲基-3-环己烯-1-酮(2.52%)等。     

白象牙芒果中挥发性成分的分析

采用同时蒸馏萃取,提取芒果果实中的挥发性成分,经气相色谱-质谱联用仪对芒果挥发性香味化合物进行分离和鉴定,确认了其中的68种成分,占总质量分数的95.40%,并用面积归一化法测定了各种成分的质量分数,其主要成分为异松油烯(44.86%)、3-蒈烯(7.06%)、棕榈酸(6.04%)、亚麻酸(3.44%)、4-蒈烯(3.14%)、苧烯(2.44%)、α-水芹烯(2.95%)等.     

常山胡柚香气成分研究

以GC／MS分析常山胡柚果皮油香气成分，鉴定出叶醇、乙醇α-蒎烯、薴烯、γ-松油烯、辛醛、癸醛，香芹醛、香紫苏醛、乙酸香叶酯、石竹烯、金合欢醇、甜橙醛、圆柚酮等五十五个成分。     

“杂樟油”前馏分化学成份的研究

用毛细管气相色谱和色 质联机等对市场俗称的“杂樟油”前馏分进行了分析研究。共鉴定出 16个化合物。其主要成分为苧烯、对伞花烃、α -异松油烯、γ -松油烯和Δ8(9) 对艹孟烯等。以上 5种成分占杂樟油前馏分总量的 94.73%。     

聚甲基丙烯酸甲酯白柠檬油微胶囊的香气品质研究

以聚甲基丙烯酸甲酯(PMMA)为壁材,白柠檬油为芯材,采用乳液聚合法制备柠檬油纳微缓释香精.为比较分析包埋前后挥发性成分的变化,采用气相色谱-质谱联用仪、电子鼻对白柠檬油和PMMA纳微缓释香精的香气物质进行了定性分析.结果表明:白柠檬油中的主要成分为柠檬烯、萜品烯、β-蒎烯、萜品油烯、γ-松油烯、α-蒎烯、α-松油醇和...     

气相色谱-质谱法分析山黄皮果皮挥发油成分

用水蒸气蒸馏法提取山黄皮果皮挥发油,经气相色谱-质谱联机分析,共分离出60个峰,鉴定出57种化合物,占总峰面积的99.89%。挥发油主要成分为:β-月桂烯、肉豆蔻醚、异松油烯、3-蒈烯、D-柠檬烯、(+)-2-蒈烯、β-水芹烯、α-水芹烯、石竹烯、丁子香酚甲基醚、(2E)-2,7-二甲基-2,6-辛二烯-1-醇、β-细辛脑,其质量分数分别为:51.50%、24.83%、12.82%、1.94%、1.15%、1.12%、0.55%、0.44%、0.43%、0.42%、0.38%、0.30%。     

Studies on pectins I. Light-scattering and w

An enzyme digestion technique for obtaining the scatter from pectin molecules in solution is described and evaluated. Weight average molecular weights, _w, calculated from the pectin scatter, are considerably higher than literature values obtained via sedimentation equilibrium experiments, but the present results are preferred. Limited comparison with a number average value, _n, obtained osmometrically, suggests that pectins can be extremely poly disperse with _w/_n = 11, for example. The relationship of intrinsic viscosity to molecular weight is a complex function of composition.     

73％片碱装置运行总结

介绍了73％片碱装置的工艺流程，对生产运行过程中出现的问题进行了分析，并采取了相应的改进措施，取得了一定的效果。     

Microencapsulation of caffeic acid and its release using a w/o/w double emulsion method: Assessment of formulation parameters

Caffeic acid (CAF)has numerous health benefits mainly due to its antioxidant, antibacterial and fungicide properties. However, its incorporation in skin care products as anti-aging and the photoprotective agent is still limited due to its solubility and stability in oily matrices or solutions balanced with the skin pH. In this research, CAF–ethyl cellulose (EC) microparticles were produced by water-in-oil-water double emulsion solvent evaporation encapsulation technique using a biocompatible polymer, EC, as a coating material and a surfactant, polyvinyl alcohol, as a stabilizer of the double emulsion. The study assessed the influence of formulation parameters as the solubility of the polymer in organic solvents and the polymer concentration on microparticles final characteristics. CAF–EC microparticles were characterized by product yield, encapsulation efficiency, mean particle size, particle size distribution and polydispersity and imaged by scanning light microscopy. In vitro release profiles were obtained in water and octanol to mimic oily based and water-based matrices balanced with the skin pH. In vitro release kinetics studies were carried out to investigate the release pattern of CAF in simulated cosmetic formulations. Both the product yield and the encapsulation efficiency were found to be dependent on the solubility of the polymer in the organic phase. The product yield was mainly affected by operational factors such as the sticking and the agglomeration of the polymer to the walls and the magnet stirring during microparticles hardening and results from the encapsulation efficiency revealed that an increase of the polymer concentration led to an increase of the encapsulation efficiency. The usage of a water-soluble solvent contributed to a decrease in the mean particle size and reduction of polydispersity with higher polymer concentrations. The polymer concentration, the polymer solubility in the organic phase and the amount of CAF entrapped shown to affect the release in water, whereas the release in octanol was mainly independent of the amount of CAF entrapped in EC microparticles. The double emulsion solvent evaporation technique and the assessment of the selected formulation conditions have given significant and innovative insights on the microencapsulation of bioactive ingredients for cosmetics formulations.     

Bildungsgeschwindigkeit von nickelhydroxidschichten wärend der kathodischen wasserstoffentwicklung

In the vicinity of a cathode where hydrogen evolution takes place, an increase of the pH-value is observed. If the solubility product of a metal hydroxide is reached in the diffusion layer or at the surface of the electrode there can be a precipitation of metal hydroxide. The kinetics of formation of Ni(OH)₂ layers at the surface of a rotating-disc electrode as a function of current density, composition of the electrolyte and thickness of the diffusion layer is being studied in the present paper.     

Die kinetik der zinkelektrode in wässrigen malonatlösungen

The kinetics of dissolution and deposition of zinc in sodium malonate solutions containing NaClO₄ as the base electrolyte was investigated. The steady state polarization curves and the frequency dependence of the faradaic impedance indicate a consecutive charge-transfer reaction with adsorbed monovalent zinc as the intermediate. The dependence of the polarization curves and of the faradaic impedances on the concentrations of malonate and zinc salt are explained by the following mechanism: During the anodic transfer reaction of zinc yielding monovalent zinc a complex with one malonate ion is formed. The subsequent oxidation to divalent zinc can follow two parallel paths of comparable rates. The charge-transfer reaction may directly yield a zinc complex with two malonate ions, or, a complex with one malonate ion may participate in the charge-transfer, the complex with two malonate ions being the product of a homogeneous reaction in solution.     

应用ASP动态网站技术制作教学软件

现代教学软件的应用主要体现于课堂教学课件的制作,主要应用的制作软件是PPT、Flash等.但这些教学软件不能做到实时更新,无法满足学生课前预习和课后复习的需要.因此针对现代教学软件的这一局限,提出应用ASP动态网站开发技术制作教学软件,并结合软件工程思想分析应用ASP动态网站开发技术制作教学软件的过程.     

Reproducibility of w/c ratio determination from fluorescent impregnated thin sections

The ease and reproducibility of preparing fluorescent epoxy impregnated thin sections for w/c determination of concrete has been studied. Five sets of thin sections were prepared from 6 concrete mixes having different compositions and w/c ratios (0.35 to 0.80). The thin sections were prepared by different technicians and produced over a period of nearly a year. The quality of the thin sections was checked and the w/c ratio determined by seven petrographers using fluorescent light microscopy as a Round Robin test.The investigation showed that, within a reasonable time, different technicians were able to produce a comparable quality of fluorescent epoxy impregnated thin sections, even though the thin sections were produced from concrete at different ages and using different equipment and chemicals. The petrographers were able to distinguish between the green shades of the fluorescent dye epoxy impregnated cement paste, with sufficient accuracy. The result of the w/c Round Robin test gave standard deviations between 0.02 and 0.03 (average 0.026).     

工业废硫酸缔合法生产硫酸钾新工艺研究

本文对硫酸钾的生产新工艺进行了研究,并着重从环保的角度利用河北省工业废硫酸为原料生产硫酸钾,提出了硫酸钾生产的最佳工艺条件。     

DAP中W(P2O5)的快速分析

贵州宏福实业开发有限总公司为了适应市场需要，总公司高层领导决定由生产重过磷酸钙改产DAP，并于2000年2月8日生产出第一批各项指标均优于国家标准规定的DAP产品。在2003年9月“宏福”牌磷酸二铵荣获中国名牌产品称号。