Factors affecting slip melting point of palm oil products

The effect of different factors affecting the slip melting point of palm oil has been evaluated. The most important factor appears to be the difference in tempering temperatures. The influence of different tempering temperatures on slip point values is, however, dependent on the nature of the sample. For hydrogenated oils and for some high-melting palm stearins, tempering has no effect. For palm oil and palm olein, higher melting points were obtained when tempering at the higher temperatures in the range of 4–15 C. For some soft stearins, however, lower melting points were obtained at the higher tempering temperatures. These effects are investigated with differential scanning calorimetry and an explanation is offered, based on phase diagrams. A secondary effect on the slip melting point was the height of fat in the capillary tube. Effects of using different methods of determination are also shown. Collaborative trials on a standard testing procedure, AOCS Cc3-25, revealed the inadequacy for palm oil of the temperature range of 4–10 C specified in the procedure and its fractions. Strict adherence to a fixed tempering temperature produced better precision and reproducibility among laboratories. Tempering at 10±1 C is recommended.     

Cold stability of red palm oleins

Cold stability of crude and refined red palm oleins was investigated. Single- and double-fractionated crude as well as refined single- and double-fractionated red palm oleins were stable against crystallization for more than 1 h but less than 2 h, whereas commercial red palm oleins remained stable for more than 5 h at 5°C. At 20°C, refined red palm oleins had better resistance to crystallization than crude palm oleins. Red palm oleins with lower amounts of saturated fatty acids (C_16:0 and C_18:0), lower levels of POP and POS triacylglycerols, and lower cloud points have increased resistance to crystallization and result in better cold stability.     

对影响餐具洗涤剂浊点和色泽因素的研究

研究了影响某种餐具洗涤荆浊点和色泽的一些因素。并对实践生产中如何控制这两项指标提出了可行性建议．     

Polymorphic stability of hydrogenated palm oleins in dilutions with unhydrogenated liquid oils

Palm oil was hydrogenated under selective and nonselective conditions. Some of the hydrogenated samples were chosen for their physical characteristics and were diluted with 70% sunflower oil. A commercial hydrogenated palm olein (H-olein) was diluted up to 80% with canola oil. The diluted mixtures were evaluated for their polymorphic β' stability by a temperature-cycling procedure between 4 and 20°C. All of the mixtures were stable in the β' form. The dropping point and solid fat content of the mixtures were compared with those of commercial soft and stick margarines. Soft margarines can be prepared from mixtures of 20% H-olein and 80% unhydrogenated oil, and stick margarines from 40% H-olein and 60% liquid oil. If canola oil is the liquid oil, the saturated content in the soft formulation is 13% and that of a stick formulation 17%.     

Multivariate determination of cloud point in palm oil using partial least squares and principal component regression based on FTIR spectroscopy

A rapid FTIR spectroscopic method was developed for quantitative determination of the cloud point (CP) in palm oil samples. Calibration samples were prepared by blending randomized amounts of palm olein and palm stearin to produce a wide range of CP values ranging between 8.3 and 47.9°C. Both partial least squares (PLS) and principal component regression (PCR) calibration models for predicting CP were developed by using the FTIR spectral regions from 3000 to 2800 and 1800 to 1600 cm⁻¹. The prediction capabilities of these calibration models were evaluated by comparing their standard errors of prediction (SEP) in an independent prediction set consisting of 14 palm oil samples. The optimal model based on PLS in the spectral range 1800-1600 cm⁻¹ produced lower SEP values (2.03°C) than those found with the PCR (2.31°C) method. FTIR in conjunction with PLS and PCR models was found to be a useful analytical tool for simple and rapid quantitative determination of CP in palm oil.     

非离子表面活性剂为溶媒的浊点萃取技术

非离子表面活性剂溶液在温度高于其浊点或有一定添加物存在时,会自动形成表面活性剂浓度很小的稀相和表面活性剂浓度很高的凝聚层相,存在于这一系统的溶质将不均匀地分配于二相。文章结合研究成果,综述了这一新型浊点萃取技术的基本理论和应用,同时也介绍了浊点萃取在微生物转化中的新应用。     

浊点萃取技术及其应用研究进展

浊点萃取是近年来发展起来的一种样品前处理技术。本文介绍了浊点萃取方法的相分离行为,讨论了关键因素如表面活性剂结构和浓度、平衡温度与时间、添加剂等对萃取效率的影响,总结了操作方法和优化。文章结合近年来的研究成果,对浊点萃取技术在金属离子、蛋白质和有机污染物分离富集中的应用进行了评述。最后探讨了浊点萃取技术的发展前景。     

Forecasting the cloud point of alkoxylated nonionic surfactants

The highest effectiveness of detergency for nonionic surfactants is observed in the proximity of the cloud point. This phenomenon is primarily influenced by surfactant molecular structure, such as carbon chain length and type of the hydrophilic components. Target of this investigation is to identify a relationship between the cloud point and the structure of nonionic surfactants based on ethoxylated (C_nE_m), ethoxylated-propoxylated (C_nE_mP_p) and propoxylated-ethoxylated (C_nP_pE_m) fatty alcohols. Three hundred and fifty nonionic surfactants have been prepared for this purpose. These surfactants differ in the C-chain lengths, C₄/C₆ to C₂₀/C₂₂, and the amount of ethylene oxide (EO range [n] 2–22 ethoxylation) and propylene oxide (PO range [p] 0–12 propoxylation) moieties. Mapping the differences in the performance allows us to propose a high-accuracy topological model describing the structure influence on the cloud point.     

农药微乳剂浊点的研究

以高效氯氰菊酯微乳剂为例,对由几种不同表面活性剂所形成的微乳剂浊点进行测定,并测了不同助表面活性剂含量时的浊点。分析讨论了影响微乳剂浊点的主要因素及其影响规律。结果表明,表面活性剂的EO加成数增加,微乳剂浊点随之升高;助表面活性剂种类及用量对浊点的影响都很大,其中乙醇、DMF对浊点都有明显的升高作用,而正丁醇可明显降低浊点,乙腈随含量的增加对浊点的影响先升高后降低。     

棕榈油市场分析

分析了2008年度的棕榈油市场发展状况,对2009年度的棕榈油市场进行了展望和预测。同时,对全球棕榈油库存及库存使用比以及在全球贸易中所占比例进行了分析。     

复合电沉积的影响因素

根据国内外电沉积金属基复合镀层的研究结果,综述了微粒特性、镀液组成、工艺条件以及其它因素对复合电沉积的影响。提出今后应继续加强在复合电沉积机理方面的研究,以便更深刻、更准确地理解和掌握复合电沉积的各种影响因素,从而更好地对复合电沉积的工艺研究和应用给予指导。     

影响酶洗涤效果因素的探讨

介绍了加酶洗涤剂的发展以及酶在洗涤剂中的应用。探讨了加酶洗涤剂中表面活性剂及其浓度、洗涤温度和洗涤时间对洗涤效果的影响,pH值对酶活性的影响。对影响酶洗涤效果的各种因素进行了阐述。并论述了酶在洗涤剂中的其他应用。     

SDS对非离子表面活性剂CM101浊点的实验分析

为深入了解掌握SDS对非离子表面活性剂CM101浊点的影响,采取实验方法,研究分析阴离子表面活性剂SDS对非离子表面活性剂CM101浊点大小的影响。通过对选取样品进行多次的实验,得出的实验结果表明:当SDS加入量为2%(W/W)时,CM101的浊点提高到59.6℃,达到农药制剂热稳定性标准要求。同时得出以下结论,非离子表面活性剂具有以下特性,即非离子表面活性剂在浊点以下能全溶于水,而在浊点以上不能全溶于水,而且非离子表面活性剂的这种特性是可逆的,且必须指出,只有非离子表面活性剂才具有浊点这一现象。     

影响E玻璃熔制质量的因素

在无碱玻璃纤维池窑拉丝生产过程中,从原料选择、配合料制备、窑炉熔化到纤维成型,影响拉丝作业的因素有很多,笔者根据本厂玻纤池窑生产的实践经验,就有关因素作一简单介绍,与同行交流。     

Antagonism between cloud point and cold filter plugging point depressants in a diesel fuel

Differential scanning calorimetry (d.s.c.) and thermomicroscopy were used to provide a better understanding of the antagonistic effect on cold filter plugging point (CFPP) when cloud point depressants (CPD) and CFPP additives are mixed into a diesel fuel. It is shown that the CFPP achieved by using only CFPP additive can be attained in the presence of CPD if a small, homogeneous size of crystals of paraffins is again obtained. Two ways are proposed to obtain this result: modification of the chemical structure of the CPD, and optimization of the concentration of each component of the blend. In either case a decrease in efficiency of the CPD is observed, but the antagonism disappears. It is possible to predict the efficiency of CFPP additives in a diesel fuel containing CPD by evaluation of T_g of the hydrocarbon matrix and determination of the percentage of light n-alkanes by d.s.c.     

Factors affecting peanut butter preference

A sensory evaluation test with 320 subjects provided information pertinent to the preference of peanut butters. Results of paired preference test indicated that more than half the subjects (59%) preferred the “old fashioned” sample; flavor (aroma and taste) would have to be the primary reason since particle size was nearly the same in the prepared test samples. Chi-square tests of independence showed that the preference for the “old fashioned” sample was dependent on age (P<.05) and sensory attributes of flavor and textural perception (P<.05). Results of the survey showed that 47% of the total responding subjects listed “crunchy” peanut butter as their favorite type. Selection of one’s favorite brand of commercial peanut butter was found to be based primarily on its particle size.     

影响柴油闪点测定值分析准确性的原因探讨

从试样含水量、试样的装入量、加热速度、点火的控制、大气压力、光线及空气流速等方面,介绍了柴油闪点测定过程中的影响因素,探讨影响分析准确性的原因。指出试样含水量的多少和加热速度的快慢对柴油闪点的测定结果影响很大。在实际工作中采取一定措施,以减小影响因素对测定结果的影响,提高柴油闪点分析的准确度。     

Factors affecting properties of sol-gel films

A relationship between the refractive index, the mirror reflection factor, the Vickers microhardness, and the chemical resistance of sol-gel films and the film thickness, inclination to crystallization, structural specifics, and composition is established.     

影响丙烯酸酯类共聚物性能的因素

综述了乳化剂用量、核、中间层、壳、粒子粒径及粒径分布等对具有核壳结构的丙烯酸酯类共聚物性能的影响。选择适量的乳化剂和交联剂，合适的反应工艺，控制丙烯酸酯类共聚物粒径及粒径分布，是得到具有良好性能丙烯酸酯类共聚物的必要条件。