共查询到17条相似文献,搜索用时 125 毫秒
1.
蓖麻油粘度随温度变化关系的理论分析与研究 总被引:1,自引:0,他引:1
粘度是液体的重要物理性质,具有重大探究价值。在大学物理实验教学中,蓖麻油常作为研究对象,基于学者对蓖麻油粘度的微观理论研究较少,本文以Eyring反应速率理论为基础,根据牛顿粘度定律和液体溶液混合规则导出蓖麻油粘度方程并进行了间接验证,在微观上解释了蓖麻油粘度随温度的变化趋势,这对物理实验教学、加深对粘度的认识和理解都具有重大帮助。 相似文献
2.
磺化酞菁镓、钒、铝、锌在水、醇、胶束中的聚合行为的研究 总被引:3,自引:0,他引:3
采用分光光度法研究了四磺化酞菁镓,钒,铝和二磺化酞菁锌在水,醇-水,胶束体系中的聚合行为,测定了配合物的二聚常数。结果表明,AlTSPc形成二聚体是一个慢反应,而GaTSPc,ZnBSPc和VOTSPc的二聚体形成是快速过程。 相似文献
3.
建立了乙醇稀释-电感耦合等离子体质谱(ICP-MS)法测定蓖麻油中多个无机微量元素的分析方法。蓖麻油样品用乙醇稀释,使用ICP-MS法直接测定。在等离子体氩气流中加入少量氧气,使高浓度有机溶液进入等离子体中完全燃烧,防止了高碳在质谱锥口和离子透镜上的冷凝沉积,采用八极杆碰撞/反应池(ORS)消除了质谱干扰,多元素(Sc,Ge,Rh,Ir)内标溶液的使用消除了基体效应,维持了各元素分析信号的稳定,通过向待测溶液中加入Au标准溶液,使元素Hg形成金汞齐消除了记忆效应。20个待测元素的线性相关系数≥0.999 5,检出限在0.06~20.1 ng·L-1之间,回收率为90.4%~110.2%,相对标准偏差(RSD)≤4.8%。通过对不同来源蓖麻油样品进行分析,结果显示,三个样品中元素的含量存在较大差异。方法能快速、简便、准确测定蓖麻油中的多个无机元素。 相似文献
4.
5.
磺化聚苯乙烯(SPS)及其离聚物的光谱特性 总被引:2,自引:1,他引:1
取苯乙烯磺化及离子化后其红外光谱产生一系列特征变化,磺化度不同的聚苯乙烯其磺酸基团伸缩振动强度不同。磺化度的提高会引起磺化聚苯乙烯(SPS)红外光谱的分裂。本外本文还就磺化聚苯乙烯及其离聚体的二氯甲烷溶液的荧光发射谱进行了讨论,结果表明,磺化程度和离子化对聚合物的荧光发射峰的强度和位置都有一定影响。 相似文献
6.
7.
通过磺化反应合成了龙血素的水溶性衍生物龙血素A-5-磺酸钠和龙血紊B-3’-磺酸钠,并采用IR、NMR、元素分析对其进行了结构表征。龙血素磺化物的合成,改善了龙血素的水溶性,为进一步研制开发龙血素类新药提供科学依据。 相似文献
8.
9.
10.
11.
Castor oil shows non-conventional physical and chemical behaviour when submitted to pressure. This paper gives a brief presentation of the specific physical properties of castor oil under pressure up to 1.0 GPa. The changes of permittivity, dielectric loss and the structure of the high-pressure induced phases of castor oil are also described. 相似文献
12.
护肤品常用的油类基质原料种类较多,其光谱特性有较大的区别,选择紫外吸收特性较好的基质原料,将使护肤品的防晒效果更加明显。文章主要是用分光光度法测定分析护肤品6种常用油类基质原料的光谱特性。分析比较T-λ光谱特性曲线说明,蓖麻油对紫外光有很好的吸收,对近红外光相比较有好的吸收,这表明护肤类产品选用蓖麻油作为基质原料,防晒效果明显增强,可以提高产品的质量。更好突出护肤类产品的防晒和保健作用。 相似文献
13.
设计了液体介质快脉冲击穿试验装置和电压电流测量系统,研究了重复频率、电极形状及电极间距与介质击穿场强、击穿电压和击穿时延等击穿特性参数的关系,比较了变压器油、十二烷基苯、蓖麻油三种典型液体绝缘介质在直流及快脉冲电压作用下的绝缘性能。结果表明:短脉冲持续时间下液体绝缘材料有异常高的击穿场强;重复脉冲串作用下的击穿场强比单个脉冲下明显减小,重复频率2 kHz时击穿场强减小了约30%;电极头半径大小对击穿也有影响,半径R=5 mm时,击穿电压最高;击穿时延随击穿场强减小而变长,在其他条件相同的情况下,测得击穿时延随机波动;蓖麻油的快脉冲电压绝缘性能最好,变压器油次之。 相似文献
14.
Saponification of oils which is a commercially important heterogeneous reaction, can be speeded up by the application of ultrasound in the presence of phase-transfer catalyst (PTC). This paper focuses on the ability of ultrasound to cause efficient mixing of this liquid-liquid heterogeneous reaction. Castor oil was taken as a model oil and the kinetic of the reaction was followed by the extent of saponification. The hydrolysis of castor oil was carried out with different PTC such as cetyl trimethyl ammonium bromide (CTAB), benzyl triethyl ammonium chloride (BTAC) and tetrabutyl ammonium bromide (TBAB) in aqueous alkaline solution. As hydroxyl anion moves very slowly from aqueous to oil phase, the presence of a PTC is of prime importance. For this purpose, cationic surfactants are selected. The sonication of biphasic system were performed by 20 kHz (simple horn and cup horn) and 900 kHz. It was found that CTAB was better than the two others and this could be related to the molecular structure of the PTCs. The effect of temperature was also studied on the saponification process. By increasing the temperature, the yield was also increased and this could be explained by intermolecular forces, interfacial tension and mass transfer. Saponification of three different vegetable oils shows that the almond oil is saponified easier than the two others and this could be related to their properties such as surface tension, viscosity and density. 相似文献
15.
Abstract Time dependencies p(t)V,T, nd V(t),P,T, at room temperature as castor oil phase transition indicators were investigated. The time after which the transition takes place, within the pressure range from 0.36 up to 1.05 GPa, strongly depends on pressure. Its minimum, at about 0.6 GPa is equal to 15 hours. Under the same conditions of experiment the largest change in volume (about ?2%) was detected. The relative changes of volume on pressure for the normal state of castor oil and for its new high pressure state have been found to be approximately the same. A large hysteresis of volume changes after the phase transition has also been observed. 相似文献
16.
The method of preparation of electroluminescent (el) cells using dielectric liquids like castor oil and liquid paraffin by an electroforming process is presented. Theel spectrum of the material derived from castor oil exhibits a large number of sharp lines which can be grouped into four distinct
series superposed on a broad background. Theel spectrum of liquid paraffin cells does not show any significant line features. The N2 laser excited fluorescence spectra of these oils and of the respective electroformed materials are also recorded. The electrical
and brightness characteristics of these cells are discussed in detail. 相似文献
17.
Assessment of barium sulphate formation and inhibition at surfaces with synchrotron X-ray diffraction (SXRD) 总被引:1,自引:0,他引:1
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