CTAB在硅胶表面吸附引起的润湿性变化和模拟驱油

用椭圆偏振法测定溴代十六烷基三甲胺（CTAB）水溶液在光滑的二氧化硅膜片上的吸附，其结果符合两阶段模型，即在不同浓度下发生单分子层和近似双分子层的吸附，并与其表面润湿性变化的数据吻合.用改进的Washburn方程测量改性硅胶粉末的润湿性, 研究了CTAB水溶液在硅胶粉末表面上吸附引起的润湿性变化.并由此探讨了CTAB水溶液在硅胶粉末表面的润湿性,表面活性剂的临界胶束浓度（CMC）与表面含油粉末脱油率的关系，对在非超低界面张力条件下通过改变固/液界面润湿性提高原油采收率作了实验探讨.     

羟基取代的烷基苯磺酸盐在水/气和水/癸烷界面的结构特点（摘要）

驱油表面活性剂的分子设计是一项重要的研究课题.设计新型高效的驱油表面活性剂关键的问题在于如何洞察表面活性剂的结构和功能的关系.长线性烷基苯磺酸盐是一类非常流行的表面活性剂,广泛应用于工业和日常生活中.关于烷基苯磺酸盐的结构和功能研究已有大量的实验和理论工作报道.近来,结合分子设计的思想,实验上合成了新型的羟基取代的烷基苯磺酸盐表面活性剂,并研究了这类新型表面活性剂动态的界面行为.我们从理论上利用分子动力学模拟的方法研究了羟基取代的烷基苯磺酸盐单分子层在水/气和水/癸烷界面的结构特点.从液体密度剖面图、氢键、表面活性剂聚集结构和有序参数等方面,详细报道了2-羟基-3-癸基-5-辛基苯磺酸钠这种新型阴离子表面活性剂的界面特征.模拟结果表明随着表面活性剂分子数目的增加,每个表面活性剂在单分子层上形成分子内氢键的平均数目将下降,但形成分子内氢键的结构仍处于主导地位;烷基尾链的疏水部分,尤其是苯环3号位上取代的癸基随着表面活性剂覆盖度增大,向界面外延伸并且更加有序;二维径向分布函数描绘了表面活性剂聚集结构的特点并暗示了癸烷相将影响表面活性剂疏水部分的取向;表面活性剂分子容易形成长程氢键结构.我们的模拟结果是对实验研究的一个重要补充.此外,模拟中我们利用gromacs和ffamber程序,使用了全原子模型,这将为模拟烷基苯磺酸盐表面活性剂的界面行为提供新的方案.     

不同体系中油酸甲酯与烷基苯磺酸盐协同效应研究

研究了表面活性剂/盐/模拟油体系与表面活性剂/碱/模拟油体系中油酸甲酯与表面活性剂协同效应机理.结果表明两种体系中协同效应机理不同.在盐体系中,油酸甲酯主要通过改变油相的等效烷烃碳数(EACN) 影响表面活性剂在油水相分配.而碱体系中,油酸甲酯影响表面活性剂在油水相分配从而影响界面张力；另一方面,油酸甲酯吸附在界面上顶替表面活性剂分子影响界面张力.对于不同结构表面活性剂,两种作用竞争的结果不同.     

纳米SiO_2在注水-驱油-油水分离中的界面调控研究进展

表面与界面行为在石油注水开发中广泛存在.功能性纳米二氧化硅具有在油-水-岩石三相界面吸附/聚集/解吸附的独特效应,有望在经济、高效和绿色环保的石油开发技术中得到应用.本文针对注水、注化学剂驱油及采出液的油水分离三个应用方向,以改变注入液-原油-岩石三相之间的界面作用为切入点,介绍了纳米二氧化硅的表面功能化及其在调控油/水/岩石三相界面中的研究进展,总结了其界面调控作用机制.最后,结合课题组研究工作,指出了功能性纳米二氧化硅表面结构调控与应用的研究方向.     

Triton X-100/甲苯/水三元体系界面张力的耗散颗粒动力学模拟

采用耗散颗粒动力学方法在介观层次上模拟了非离子表面活性剂Triton X-100 在油/水界面上的分布行为, 并把用于油/水二元体系界面张力的计算方法拓展到含表面活性剂的三元体系. 利用该方法可以得到与实验数值吻合的界面张力数据. 另外, 模拟结果直观展示了表面活性剂界面张力与界面密度的关系, 为表面活性剂复配增效理论提供了依据. 该模拟方法给出的微观信息可以为驱油体系配方筛选和表面活性剂有效应用提供指导.     

阴离子Gemini表面活性剂在油/水界面行为的分子动力学模拟

采用分子动力学方法研究了磺酸盐型阴离子Gemini表面活性剂在油/水界面的吸附行为, 考察了不同长度的连接基(Spacer)对表面活性剂在界面的聚集形态及界面性质的影响. 密度分布和微观结构信息显示, Gemini表面活性剂能在油/水界面形成单层膜结构. Gemini表面活性剂能使油/水界面的厚度显著增大, 并使界面形成能降低. 当连接基为6个碳时, 此类磺酸盐型Gemini表面活性剂的界面厚度最大, 形成的界面最稳定. 连接基长度对Gemini表面活性剂单层膜周围的水分子和Na⁺的吸附结构影响不大, 但是能影响水分子的扩散行为.     

以油酸为原料的新型生物基支链十七烷基苯磺酸钠的合成及性质

生物基表面活性剂由于其可再生资源和优异的表面/界面性质吸引了越来越多的关注。本文以可再生的油酸为原料,通过四步反应,制备了新型生物基支链表面活性剂,并评价了其表/界面性质、润湿性和生物降解性能。该新型生物基支链表面活性剂为4-（1-十七烷基）苯磺酸钠（9ΦC17S）,依次经过烷基化反应、脱羧反应、磺化反应和中和反应而制得。其化学结构已通过电喷雾质谱、红外光谱和核磁共振波谱得以确认。4-（1-十七烷基）苯磺酸钠展现出良好的表/界面张力,临界胶束浓度（CMC）为317.5 mg·L^-1,CMC处的表面张力为32.54 mN·m^-1,当水溶液中碳酸钠浓度为8.48×10⁴ mg·L^-1、4-（1-十七烷基）苯磺酸钠浓度为8.36×10⁴ mg·L^-1时,油水的界面张力约为10^-2 mN·m^-1。此外,4-（1-十七烷基）苯磺酸钠在生物降解性和润湿性方面也显示出了良好的性能,最终生物降解评分为2.99,0.500 g·L^-1 9ΦC17S溶液的气液固接触角为63.08°。该新型生物基表面活性剂丰富了以可再生资源为原料的生物基表面活性剂的结构多样性。     

烷基苯磺酸盐在油水界面行为的介观模拟

采用耗散颗粒动力学(DPD)方法在介观层次上模拟了表面活性剂烷基苯磺酸盐在油/水界面的排布行为, 考察了分子结构、浓度、盐度、油相等因素对表面活性剂界面密度和界面效率的影响, 并探讨了利用表面活性剂复配协同效应提高界面活性的理论机制. 分子模拟给出的分子水平的微观信息为强化采油技术中配方筛选和表面活性剂的有效应用提供指导.     

CMC型高分子表面活性剂在固/液界面上的吸附

在润湿、乳化、洗涤、分散等应用领域中,表面活性剂分子在界面上的吸附状态对性能有重要影响.另一方面,在化学驱油过程中,表面活性剂分子在氧化物矿物上的吸附是引起表面活性剂损失的主要原因,表面活性剂的损耗量大,将降低采收率及经济效益[1].高分子表面活性剂作为一种多功能的新型表面活性剂在许多领域有广阔的应用前景,但对其性能研究尚处于起步阶段,特别是结构复杂的高分子双亲性共聚物,在吸附、乳化等方面研究尚少报导.羧甲基纤维素系列高分子表面活性剂是采用独特的超声波辐照技术合成的嵌段型共聚物,具有优良的表/界面活性[2],可望用…     

阴离子表面活性剂在水/正烷烃界面的分子动力学模拟(英文)

利用分子动力学模拟方法研究了阴离子表面活性剂在水/正烷烃(壬烷,癸烷和十一碳烷)界面的结构和动力学特点.十六烷基苯磺酸钠作为研究对象,其中苯磺酸基团在十六碳烷的第4号碳原子上,记作4-C16.分析了不同油相和特定盐度条件下正烷烃-表面活性剂-水体系的界面特点(如密度剖面图、界面张力和径向分布函数).模拟结果表明平衡模型体系展现了一个很好的水/正烷烃界面.当加氯化钠到水溶液中,正烷烃-表面活性剂-水体系的界面张力有微小的变化,有趣的是表面活性剂二面角的反式结构分数的变化联系着界面张力的微小变化.可见,表面活性剂在界面处的结构对降低界面张力起到重要的作用.此外,还发现表面活性剂的极性头与钠离子和水分子存在较强的相互作用.     

Determination of betaines in vegetable oils by capillary electrophoresis tandem mass spectrometry--application to the detection of olive oil adulteration with seed oils

A CE–tandem mass spectrometry (MS²) methodology enabling the simultaneous determination of betaines (glycine betaine, trigonelline, proline betaine and total content of carnitines) in vegetable oils was developed. Betaines were derivatized with butanol previous to their baseline separation in 10 min using a 0.1 M formic acid buffer at pH 2.0. Ion trap conditions were optimized in order to maximize the selectivity and sensitivity. Analytical characteristics of the proposed method were established by evaluating its selectivity, linearity, precision (RSDs ranged from 4.8 to 10.7% for corrected peak areas) and accuracy by means of recovery studies (from 80 to 99%) and LODs and LOQs at 0.1 ppb level. The method was applied for the determination of the selected betaines in seed oils and extra virgin olive oils. MS² experiments provided the fingerprint fragmentation for the betaines identified in vegetable oils. In extra virgin olive oils, carnitines were not detected, making it possible to propose them as a feasible novel marker for the detection of adulterations of olive oils. Application of the developed method for the analysis of different mixtures of extra virgin olive oil with seed oil (between 2 and 10%) enabled the detection and quantitation of the total content of carnitines. The results obtained show the high potential of the developed method for the authentication and quality control of olive oils.     

Pyrolysis of vegetable oil soaps—Palm, olive, rapeseed and castor oils

Saponified, palm, olive, rapeseed and castor oils were pyrolysed (at 750 °C for 20 s) by pyrolysis gas chromatography with mass selective and flame ionisation detection (Py-GC/MSD and FID) to clarify their thermochemical behaviours. The liquefiable compounds recovered from palm, olive and rapeseed oils mainly contained linear alkenes (up to C₁₉) and alkanes (up to C₁₇), both similar to those found in gasoline (C₄-C₁₀) and diesel fuel (C₁₁-C₂₂) boiling range fractions of petroleum, whereas in the case of castor oil a significant amount of undesired oxygen-containing products (e.g., ketones and phenols) were formed. The obtained data on reaction mechanisms can also be utilised in applications where various biofuels are produced, for example, from the extractive-derived by-product (tall oil) of kraft pulping.     

An Intricate Review on Nutritional and Analytical Profiling of Coconut,Flaxseed, Olive,and Sunflower Oil Blends

Vegetable oils (VOs), being our major dietary fat source, play a vital role in nourishment. Different VOs have highly contrasting fatty acid (FA) profiles and hence possess varying levels of health protectiveness. Consumption of a single VO cannot meet the recommended allowances of various FA either from saturated FA (SFA), monounsaturated FA (MUFA), polyunsaturated FA (PUFA), Ω-3 PUFAs, and medium-chain triglycerides (MCTs). Coconut oil (CO), flaxseed oil (FO), olive oil (OO), and sunflower oil (SFO) are among the top listed contrast VOs that are highly appreciated based on their rich contents of SFAs, Ω-3 PUFAs, MUFAs, and Ω-6 PUFA, respectively. Besides being protective against various disease biomarkers, these contrasting VOs are still inappropriate when consumed alone in 100% of daily fat recommendations. This review compiles the available data on blending of such contrasting VOs into single tailored blended oil (BO) with suitable FA composition to meet the recommended levels of SFA, MUFA, PUFA, MCTs, and Ω-3 to Ω-6 PUFA ratios which could ultimately serve as a cost-effective dietary intervention towards the health protectiveness and improvement of the whole population in general. The blending of any two or more VOs from CO, FO, OO, and SFO in the form of binary, ternary, or another type of blending was found to be very conclusive towards balancing FA composition; enhancing physiochemical and stability properties; and promising the therapeutic protectiveness of the resultant BOs.     

环氧化植物油的制备

天然油脂在无溶剂加压（约０．１５ＭＰａ）条件下，经甲酸（８５％）、双氧水（５０％）环氧化，一步合成增塑剂兼稳定剂环氧化油脂，得微黄色油状透明液体；环氧大豆油和环氧葵子油的环氧值均在６．２％～６．６％，环氧玉米油的环氧值６．０％～６．４％；碘值小于３ｍｇ／ｇ；精油转化率１０４％～１０８％。     

A novel approach to the rapid assignment of 13C NMR spectra of major components of vegetable oils such as avocado,mango kernel and macadamia nut oils

Assignment of ¹³C nuclear magnetic resonance (NMR) spectra of major fatty acid components of South African produced vegetable oils was attempted using a method in which the vegetable oil was spiked with a standard triacylglycerol. This proved to be inadequate and therefore a new rapid and potentially generic graphical linear correlation method is proposed for assignment of the ¹³C NMR spectra of major fatty acid components of apricot kernel, avocado pear, grapeseed, macadamia nut, mango kernel and marula vegetable oils. In this graphical correlation method, chemical shifts of fatty acids present in a known standard triacylglycerol is plotted against the corresponding chemical shifts of fatty acids present in the vegetable oils. This new approach (under carefully defined conditions and concentrations) was found especially useful for spectrally crowded regions where significant peak overlap occurs and was validated with the well‐known ¹³C NMR spectrum of olive oil which has been extensively reported in the literature. In this way, a full assignment of the ¹³C{1H} NMR spectra of the vegetable oils, as well as tripalmitolein was readily achieved and the resonances belonging to the palmitoleic acid component of the triacylglycerols in the case of macadamia nut and avocado pear oil resonances were also assigned for the first time in the ¹³C NMR spectra of these oils. Copyright © 2009 John Wiley & Sons, Ltd.     

Effects of Thai Local Ingredient Odorants,Litsea cubeba and Garlic Essential Oils,on Brainwaves and Moods

The functional food market is growing with a compound annual growth rate of 7.9%. Thai food recipes use several kinds of herbs. Lemongrass, garlic, and turmeric are ingredients used in Thai curry paste. Essential oils released in the preparation step create the flavor and fragrance of the famous tom yum and massaman dishes. While the biological activities of these ingredients have been investigated, including the antioxidant, anti-inflammatory, and antimicrobial activities, there is still a lack of understanding regarding the responses to the essential oils of these plants. To investigate the effects of essential oil inhalation on the brain and mood responses, electroencephalography was carried out during the non-task resting state, and self-assessment of the mood state was performed. The essential oils were prepared in several dilutions in the range of the supra-threshold level. The results show that Litsea cubeba oil inhalation showed a sedative effect, observed from alpha and beta wave power reductions. The frontal and temporal regions of the brain were involved in the wave alterations. Garlic oil increased the alpha wave power at lower concentrations; however, a sedative effect was also observed at higher concentrations. Lower dilution oil induced changes in the fast alpha activity in the frontal region. The alpha and beta wave powers were decreased with higher dilution oils, particularly in the temporal, parietal, and occipital regions. Both Litsea cubeba and turmeric oils resulted in better positive moods than garlic oil. Garlic oil caused more negative moods than the others. The psychophysiological activities and the related brain functions require further investigation. The knowledge obtained from this study may be used to design functional food products.     

傅里叶变换红外吸收光谱识别五种植物油的研究

以花生油、大豆油、芝麻油、棉籽油和米糠油为样品,采用傅里叶变换红外光谱仪,采集傅里叶变换红外吸收光谱,对光谱预处理后,提取红外特征信息,以1746cm-1和2855cm-1处的吸收峰面积比值为横坐标,1099cm-1处与1119cm-1处的吸收峰面积比为纵坐标,在Origin6.0上做出二维分布图,对各种油脂进行识别分析。结果显示,大豆油与其它4种油脂之间有明显区分;大豆油、花生油和芝麻油分布效果好,但棉籽油各样品点之间比较分散;能与其它油脂区分开的有以下几种分布花生油明显区别于芝麻油、棉籽油和大豆油;米糠油明显区别于棉籽油和大豆油。分布有交叉的油脂有米糠油与花生油或芝麻油有交叉,棉籽油与芝麻油有交叉。     

Determination of acrolein in french fries by solid-phase microextraction gas chromatography and mass spectrometry

The frying of foods in the home can be a cause of indoor pollution due to the formation of acrolein. The emission of acrolein formed during frying in soybean, corn, canola, sunflower and palm oils was studied. A GC/MS method has been developed to determine acrolein in French fries using SPME as the sampling technique after derivatization with 2,4-dinitrophenylhydrazine (DNPH). Optimum SPME conditions included desorption at 250°C for 2min after an adsorption time of 10min at room temperature. The method presented good resolution, repeatability, detection and quantification limits, and linearity of response. French fries were prepared in five different oils with four frying steps. The results showed that changes in acrolein concentration occurred after frying potatoes in different types of oil and at different frying cycles. Potatoes fried in soybean oil contained the lowest concentration of acrolein. Shoestring potatoes contained a lower concentration of acrolein than potato chips and French fries, respectively, because of the higher surface/volume ratio.     

用NICOLET5SXC富里利叶变换红外光谱仪对中成药作GC/FTCR分析研究——Ⅱ.药用油的GC/FTIR快速分析

本文用Nicolet 5SXC对驱风油,本草油,白花油进行了GC/FTIR快速分析,在没有标准品的条件下,对其中十六个主组分进行了定性研究,用Aldrich Vapor Librasy进行了谱库检索,取得了较为满意的结果。     

四苯(基)苯基多乙烯基硅油的合成及结构测定

<正> 多乙烯基硅油是高温硫化硅橡胶的集中交联剂,当无耐热填料时,所得硫化胶的耐热性不高。为了使多乙烯基硅油既具有集中交联作用,又赋予耐热性,本文采用Diels-AIder反应合成了含有四苯(基)苯基的多乙烯基硅油。前文曾合成多种多苯(基)苯基有机硅化合物,但实验在封管内进行,诸多不便,投量也甚少,为此,改用高沸点溶剂(α-氯萘),在常压下反应,得到了高产率的四苯(基)苯基多乙烯基硅油: