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1.
巴豆种子油的GC-MS分析   总被引:8,自引:0,他引:8  
梁英  潘英明 《光谱实验室》2002,19(6):748-750
巴豆种子经石油醚或无水乙醇提取得巴豆种子油,通过气相色谱-质谱联用仪(GC-MS)测定其中的化学夸分,结果显示,巴豆种子油中含有26个组分,本文确定了其中22个组分的结构。  相似文献   

2.
中相微乳液的形成和特性   总被引:4,自引:0,他引:4  
在双-2-乙基已基琥珀酸磺酸钠-醇-正辛烷-盐水体系中,它们能形成多相微乳液,本文系统研究了表面活性剂的浓度(1.0-7.0%),醇的种类(乙醇,正丙醇,正丁醇,正戊醇)和其浓度(1.0-7.0%)以及油的种类等因素,对其中相微乳液的形成和特性的影响,这些特性(最佳含盐量S,盐宽△S,界面张力等)对于实际应用是非常重要的,最后还与十二烷基磺酸的钠体系进行了对比,并对其中得到的规律在理论上进行探讨。  相似文献   

3.
Si{111}的吸附表面结构   总被引:1,自引:1,他引:0  
利用低能电子衍射研究了金属和非金属吸附在Si{111}表面的表面结构。结果显示出:对Al、Ga、Bi和Au原子,形成α-Si{111}3×3R30°-M或β-Si{111}3×3R30°-M结构的共价吸附。对Li、Na和Ag原子,形成正离子吸附,全部经高温解吸后,便诱导出Si{111}1×3重构。对Te原子,形成负离子吸附,经高温解吸后,便诱导出Si{111}类(1×1)结构。  相似文献   

4.
对[μ-CF_3CO_2)_2Ln(μ-CF_3HCO_2)Al(i-Bu)_2·THFl_2(Ln=Nd,Y)配合物单晶结构的X-射线分析指出,配合物具有中心对称性,配位中心由两个稀土和两个Al离子组成,稀土由两个THF和6个TFA分子配位形成畸变的三盖三棱柱结构,Al由两个TFAG和两个i-Bu配位形成四面体结构。桥连Al与两个稀土的TFA分子的羧基发生歧化加氢,其碳原子由SP ̄2型转变为SP ̄3型.NMR研究表明,在THF溶液中,该配合物保持了它在单晶中的配位结构,所不同的是两个i-Bu在溶液中有两种异构形成,二者间为慢交换过程。  相似文献   

5.
实验发现硫脲能在电极表面形成一吸附层并阻碍氢在电极表面的析出还原反应,此吸附层在电位约-0.6V时发生结构转变,进一步实验显示硫脲吸附层的结构在-0.9V时为疏松的,在-0.3V~-0.5V时为致密的,而在-0.8V~-0.6V时为两种结构的中间过渡态。  相似文献   

6.
稀释磁性半导体   总被引:12,自引:0,他引:12  
稀释磁性半导体是指Ⅱ-Ⅵ族、Ⅳ-Ⅵ族、Ⅱ-Ⅴ族或Ⅲ-Ⅴ族化合物中,由磁性过渡族金属离子或稀土金属离子部分地替代非磁性阳离子所形成的新的一类半导体材料。这类材料的突出特点是磁性离子磁矩和能带电子自旋之间存在交换相互作用。由此引起材料性质发生一系列重要变化。本文系统介绍这类材料的各种物理性质,包括能带结构,sp-d和d-d交换作用,磁性质和自旋玻璃特性,光学和磁学性质,输运特性等。最后简单介绍这类材料  相似文献   

7.
对于H+n的形成,艹勾清泉教授指出,可先以H+离子为中心,瞬时地分别与周围(n-1)个H原子相互作用,形成中心氢核同周围氢核间的(n-1)个瞬时单电子键,这些单电子键围绕中心转动共振,从而使H+吸引周围(n-1)个H原子形成H+n团簇。对采用此模型计算的H+n(n=5,7,9,13)的正多面体中心结构结果,作了规律性的总结,获得了对H+n团簇结构的进一步认识  相似文献   

8.
研究了铕(Ⅲ)与α-萘甲酰呋喃甲酰甲烷(α-NMFM),1,10-邻菲罗啉(Phen)形成的二元和三元配合物的核磁共振氢谱及红外光谱,推测了配合物的结构。  相似文献   

9.
Ni(II)与壳聚糖的配位作用及其催化性质的研究   总被引:7,自引:0,他引:7  
用ESR、XPS、IR、UV-Vis、DTA-TG和电导率法研究Ni(Ⅱ)与壳聚糖(CS)的配位作用、所形成的配位聚合物(配聚物)的组成和结构。确定Ni(Ⅱ)与CS分子以配位键相结合形成高自旋Ni-CS配聚物,配聚物的配位单元由1个Ni(Ⅱ)与3个CS单体单元的氨基N原子和仲羟基O原子形成扭曲的六配位的八面体结构所组成。此外,对Ni-CS配聚物与Na2SO3体系在MMA聚合中的催化性质进行了研究。  相似文献   

10.
研究了铕(III)与α-萘甲酰呋喃甲酰甲烷(α-HNFM),1,10-邻菲啉(Phen)形成的二元和三元配合物的核磁共振氢谱及红外光谱,推测了配合物的结构。  相似文献   

11.
Spray, ignition and combustion characteristics of biodiesel fuels were investigated under a simulated diesel-engine condition (885 K, 4 MPa) in a constant volume combustion vessel. Two biodiesel fuels originated from palm oil and used cooking oil were used while JIS#2 used as the base fuel. Spray images were taken by a high speed video camera by using Mie-scattering method to measure liquid phase penetration and liquid length. An image intensifier combined with OH filter was used to obtain OH radical image near 313 nm. Ignition and combustion characteristics were studied by OH radical images. Biodiesel fuels give appreciably longer liquid lengths and shorter ignition delays. At low injection pressure (100 MPa), biodiesel fuels give shorter lift-off lengths than those of diesel. While at high injection pressure (200 MPa), the lift-off length of biodiesel fuel originated palm oil gives the shortest value and that of biodiesel from used cooking oil gives the longest one. Air entrainment upstream of lift-off length of three fuels was estimated and compared to soot formation distance. This study reveals that the viscosity and ignition quality of biodiesel fuel have great influences on jet flame structure and soot formation tendency.  相似文献   

12.
流体动力式发声器在采油工业中的应用研究   总被引:6,自引:0,他引:6  
路斌 《物理》2004,33(4):278-281
流体动力式声波发生器是一种有着悠久历史的声处理发生器 ,具有成本低廉、结构简单、坚固耐用以及动力源方便等特点 .在采油工业中 ,利用这种声处理技术可以降低原油粘度 ,改善原油物性以及地层渗流条件 ,达到最终提高采收率的目的 .文章论述了几种具有实际应用效果的流体动力式声波发生器在采油工业中的应用研究进展 ,并从作用机理、实验研究、现场应用等方面进行了详细的介绍 .  相似文献   

13.
There has been consistent drive towards research and innovation in oil production technologies in order to achieve improved effectiveness and efficiency in their operation. This drive has resulted in breakthrough in technologies such as the application of ultrasound (US) in demulsification and enhanced oil recovery (EOR), and usage of high-volume hydraulic fracturing and special horizontal well for shale oil and gas extraction. These can be observed in the increment in the number of commercial oil technologies such as EOR projects that rose from 237 in 1996 to 375 in 2017. This sustained expansion in EOR resulted in their total oil production rising from 1.5 million barrels per day in 2005 to 2.3 million barrels per day in 2020. And this is predicted to increase to about 4.7 million barrels per day in 2040, which represent about 4% of total production. Consequently, in this review, the developments in the utilization of US either as standalone or integrated with other technologies in EOR and dehydration of water in oil emulsions were analyzed. The studies include the optimization of fluid and US properties in EOR and demulsification. Reports on the treatment of formation damage resulting from inorganic salts, organic scales, drilling fluid plugs, condensate, paraffin wax and colloidal particle with US-assisted EOR were also highlighted. Moreover, the mechanisms were examined in order to gain insightful understanding and to aid research investigations in these areas. Technologies such as US assisted green demulsification, high intensity focused ultrasound, and potential pathways in field studies were assessed for their feasibilities. It is essential to evaluate these technologies due to the significant accrued benefits in them. The usage of green demulsifiers such as deep eutectic solvents, ionic liquids and bio-demulsifiers has promising future outlook and US could enhance their technical advancement. HiFU has been applied successfully in clinical research and developments in this area can potentiality improve demulsification and interfacial studies (fluid–fluid and solid–fluid interactions). As regards field studies, there is need to increase actual well investigations because present reports have few on-site measurements with most studies being in laboratory scale. Furthermore, there is need for more detailed modeling of these technologies as it would assist in conserving resources, saving research time and fast-tracking oil production. Additional evaluative studies of conditions such as the usage of Raschig rings, crude oil salinity and high temperature which have improved demulsification of crude oil emulsions should be pursued.  相似文献   

14.
摘要:本文重点研究油湿型方解石表面形成的过程和方解石表面油膜在SO42-作用下脱附的过程,从分子尺度探究油膜形成机理和SO42-作用机理。首先,为模拟碳酸盐岩储层实际而建立油湿型碳酸盐岩表面。范德华力和静电作用下油分子运动到方解石表面形成双层结构的油膜,方解石由水湿变为油湿。结果表明,与第二层相比,第一层排列更有序,结构更稳定,对储层润湿性影响更大。而后,研究方解石表面油膜在SO42-作用下脱附的过程和作用机理。方解石表面油膜的脱附可以分为两步:静电作用下水通道的形成;氢键作用下水膜的形成。最终,方解石表面由油湿变为水湿。研究表明:SO42-参与了方解石表面油膜脱附过程中重要的静电力作用和氢键作用,加速了水通道和水膜的形成,加速了方解石表面油膜的脱附,对储层润湿性影响较大。  相似文献   

15.
The precipitation of barium sulphate from aqueous supersaturated solutions is a well-known problem in the oil industry often referred to as ‘scaling’. The formation and growth of barite on surfaces during the oil extraction process can result in malfunctions within the oil facilities and serious damage to the equipment. The formation of barium sulphate at surfaces remains an important topic of research with the focus being on understanding the mechanisms of formation and means of control.In situ synchrotron X-ray diffraction (SXRD) was used to investigate the formation of barium sulphate on a stainless steel surface. The effect of Poly-phosphinocarboxylic acid (PPCA) and Diethylenetriamine-penta-methylenephosphonic acid (DETPMP) which are two commercial inhibitors for barium sulphate was examined. The in situ SXRD measurements allowed the identification of the crystal faces of the deposited barite in the absence and presence of the two inhibitors. The preferential effect of the inhibitors on some crystal planes is reported and the practical significance discussed.  相似文献   

16.
We report for the first time the generation of electrified coaxial jets of micrometric diameter in liquid media. Scaling laws to predict the inner and outer diameter of the coaxial jet are given. We show some experiments illustrating the formation process of the coaxial jet, and demonstrate how this process can be used to yield either o/w (oil in water) or o/w/o (oil/water/oil) emulsions of micrometric size. Some interesting analogies with other hydrodynamic focusing processes are also pointed out.  相似文献   

17.
The present work deals with emulsions of volatile alkanes in an aqueous clay suspension, Laponite, which forms a yield stress fluid. For a large enough yield stress (i.e. Laponite concentration), the oil droplets are prevented from creaming and the emulsions are thus mechanically stabilized. We have studied the evaporation kinetics of the oil phase of those emulsions in contact with the atmosphere. We show that the evaporation process is characterized by the formation of a sharp front separating the emulsion from a droplet-free Laponite phase, and that the displacement of the front vs. time follows a diffusion law. Experimental data are confronted to a diffusion-controlled model, in the case where the limiting step is the diffusion of the dissolved oil through the aqueous phase. The nature of the alkane, as well as its volume fraction in the emulsion, has been varied. Quantitative agreement with the model is achieved without any adjustable parameter and we describe the mechanism leading to the formation of a front.  相似文献   

18.
The conditions for transition to a state of supercritical (SC) fluid in the hydrocarbons-water system are examined. A method for thermochemical heating the productive stratum near the oil well involving the transition of the oil-water formation fluid to the SC state (homogeneous, inseparable, and extremely fluid) is proposed. New chemical compositions, binary mixtures (BMs) of nitrates of organic amines (organic nitrate) and initiators of their decomposition, capable of ensuring the transition of the fluid to the supercritical state at the expense of high pressures and temperatures generated by rock pressure and heat of the exothermic reaction of BM are tested. The effectiveness of the scheme of production of formation fluid in waterflooded oil fields is assessed.  相似文献   

19.
Failure of paper oil insulation due to formation of copper sulphide in transformer windings is a serious issue affecting the performance and life of large transformers. Though chemical effects leading to corrosion are well understood, quantification of electric stress and its correlation to formation and migration of copper sulphide has not been reported in literature. Hence electric stress distribution under copper corrosion using FEM simulation has been studied and discussed in this paper. The simulation results are compared and correlated to experimental findings. The study clearly points towards increase in electric stress in unaffected paper and non-uniform electric stress distribution in paper–oil insulation system. Implications of using enamel coating on copper conductor as a mitigation technique to combat copper corrosion is also discussed.  相似文献   

20.
The synthesis and characterization of polyacrylamide/clay nanocomposites for the development of hydrogel system used in enhanced oil recovery is described. The synthesized nanocomposite copolymer was crosslinked with Chromium (III) acetate to form the hydrogel which exhibited an acceptable gel strength, gelation time and gel stability. The nanocomposite gels prepared with low crosslinker concentration (2000 ppm chromium acetate) showed higher gel strength and required longer gelation time than the conventional polyacrylamide (PAAm) gel; these are desirable properties for the effective placement of gel during enhanced oil recovery operations. The effects of various parameters, such as polymer and crosslinker concentration, on the gelation time and gel strength were evaluated using the bottle testing method. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM) revealed the formation of intercalated and exfoliated clay morphologies. The effects of the clay content on the thermal stability and gel strength of the gel network were also investigated by thermogravimetric analysis (TGA) and rheological measurements (oscillatory time sweep profiles), respectively. Also, in-situ gelation and core flooding experiments revealed that a significant permeability reduction of the sand pack cores could be achieved at reservoir conditions when they were treated with the developed nanocomposite gel formulation. Hence, this nanocomposite gel system with low crosslinker concentration (10,000 ppm of nanocomposite polymer concentration containing 2000 ppm of clay with 2000 ppm chromium acetate crosslinker) may be suitable in water shut-off treatments required for enhanced oil recovery from the oil fields.  相似文献   

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