JH-4548芳胺型聚醚多元醇的研制

介绍了JH-4548芳胺型聚醚多元醇的制备方法,讨论了聚醚起始剂种类、配比及合成工艺对JH-4548芳胺型聚醚多元醇质量及其合成的聚氨酯仿木结构硬泡性能的影响.结果表明,以芳胺化合物质量分数15%～20%,蔗糖5%～20%,山梨醇10%,甘油50%～70%制成复合起始剂;首批环氧丙烷(PO)加入量占总PO质量分数的25%时,与起始剂聚合所得聚醚的活性高,粘度适中,由它制备的聚氨酯仿木结构硬泡,可应用于汽车仪表盘骨架.     

Odor Significance of the Volatiles Formed During Deep-Frying With Palm Olein

Palm olein is currently considered to be one of the best options for deep-frying, but as with any other edible oil, during frying, deteriorative reactions produce off-flavor compounds that reduce the oil sensory quality. This study assessed the odor significance of the volatiles formed during 136 h of deep-frying a chicken product in palm olein, aiming to identify potential markers of the oil sensory quality during frying. The volatiles were isolated by solid phase microextraction, and identified by GC–MS. Trained judges assessed the odor intensity and quality of the volatiles formed during frying, evaluating the GC effluents through a GC–olfactometry technique called OSME. Two hundred and eight volatiles were detected by GC/MS in the palm olein after 136 h frying. Of these, heptanal, t-2-heptenal, decanal and t-2-undecenal were identified as potential markers of the sensory quality of palm olein during frying. Hexanal, pentanal and pentane, usually associated with lipid oxidation, showed no odor impact in the GC effluents, and were thus proven not to be good markers of the sensory quality of palm olein when used for a long frying period.     

Environmental and economic feasibility of palm oil biodiesel in the Mexican transportation sector

This study analyses the environmental and economic feasibility of producing palm oil-based biodiesel in Mexico in order to substitute of diesel fuel consumption using B5 until 2015 and B10 from 2016 to 2031 in the transportation sector. Two scenarios were created by projecting demand and costs for biodiesel as well as greenhouse gases emissions reduction over the next 26 years. In the environmental section, avoided emissions of Particulate matter, Total Hydrocarbons, Carbon Monoxide, Sulphur Dioxide, and Carbon Dioxide as well as the increase in Nitrous Oxide emissions were estimated for each scenario. In the economic section, a cost–benefit analysis of biodiesel substitution was implemented, and mitigation costs of Carbon Dioxide were estimated. Our results show that the feasibility of palm oil biodiesel use is directly related to the implementation of fiscal incentives, such as the exemption from tax (Special Tax on Production and Services).     

Influence of precursors on the formation of 3‐MCPD and glycidyl esters in a model oil under simulated deodorization conditions

To find new ways for reducing the potential of palm oil to form 3‐monochloropropane‐1,2‐diol (3‐MCPD) and glycidyl esters during refining it is helpful to know more about the influence of different precursors like diacylglycerols (DAGs) and monoacylglycerols (MAGs), lecithin, and chlorine containing compounds. After adding increasing amounts of the different precursors to a model oil obtained by removal of polar compounds from crude palm oil and heating the mixture under standardized conditions to 240°C for 2 h the contents of 3‐MCPD and glycidyl esters were analyzed according to the standard procedure of DGF C‐VI 18 (10). DAGs and MAGs were found to increase the potential of palm oil to form 3‐MCPD and glycidyl esters, but refined lecithin showed no influence. Sodium chloride as well as tetra‐n‐butylammoniumchloride (TBAC) led to higher contents of the esters. Whereas the addition of TBAC raised the amount of glycidyl esters as well as 3‐MCPD esters, sodium chloride largely raised the amount of 3‐MCPD esters. An addition of 5 mmol of sodium carbonate/kg model oil spiked with sodium chloride reduced the amount of glycidyl esters almost completely; the 3‐MCPD esters were reduced by 50%. About 1 mmol sodium hydrogen carbonate/kg oil reduced both 3‐MCPD and glycidyl esters almost completely. Practical applications : For the mitigation of the formation of 3‐MCPD esters and related compounds in refined edible oils, it is helpful to know more about the effect of different possible precursors. Using a broader data basis, it is possible to adopt the oil processing but especially the choice of the raw material to the demands of the market for lower contents of the esters in the refined products.     

Thermal analysis of cylinder head carbon deposits from single cylinder diesel engine fueled by palm oil–diesel fuel emulsions

This paper aims to evaluate the cylinder head carbon deposit from diesel engine fuelled by four samples of diesel fuel emulsions containing 0%; 5%; 10% and 15% vol. water and 20% Palm Oil Methyl Ester (POME) were subjected to thermogravimetric analysis (TGA/DSC) in air medium. The deposit build up processes were performed on a single-cylinder direct-injection diesel engine for period of 25 h for each set of test fuel under constant speed 2500 rpm. The TGA system was used and then correlated with elemental analysis as well as infrared spectra for microscopic observations. It has been found that, as the water increases in fuel, less aromatic and less reactive of deposits would be formed. Therefore, such method of analyses can be used as an indicator to verify the stability of carbon deposit inside the combustion chamber that could substantiate the applicability of a particular fuel to be accepted.     

Effects of torrefaction on the physiochemical properties of oil palm empty fruit bunches,mesocarp fiber and kernel shell

In this work, the effects of torrefaction on the physiochemical properties of empty fruit bunches (EFB), palm mesocarp fiber (PMF) and palm kernel shell (PKS) are investigated. The change of properties of these biomass residues such as CHNS mass fraction, gross calorific value (GCV), mass and energy yields and surface structure when subjected to torrefaction process are studied. In this work, these materials with particle size in the range of 355–500 μm are torrefied under light torrefaction conditions (200, 220 and 240 °C) and severe torrefaction conditions (260, 280 and 300 °C). TGA is used to monitor the mass loss during torrefaction while tube furnace is used to produce significant amount of products for chemical analyses. In general, the study reveals torrefaction process of palm oil biomass can be divided into two main stages through the observation on the mass loss distribution. The first stage is the dehydration process at the temperature below than 105 °C where the mass loss is in the range of 3–5%. In the second stage, the decomposition reaction takes place at temperature of 200–300 °C. Furthermore, the study reveals that carbon mass fraction and gross calorific value (GCV) increase with the increase of torrefaction temperature but the O/C ratio, hydrogen and oxygen mass fractions decrease for all biomass. Among the biomass, torrefied PKS has the highest carbon mass fraction of 55.6% when torrefied at 300 °C while PMF has the highest GCV of 23.73 MJ kg⁻¹ when torrefied at the same temperature. Both EFB and PMF produce lower mass fraction than PKS when subjected to same torrefaction temperature. In terms of energy yield, PKS produces 86–92% yield when torrefied at light to severe torrefaction conditions, until 280 °C. However, both EFB and PMF only produce 70–78% yield at light torrefaction conditions, until 240 °C. Overall, the mass loss of 45–55% of these biomasses is observed when subjected to torrefaction process. Moreover, SEM images reveal that torrefaction has more severe impact on surface structure of EFB and PMF than that of PKS especially under severe torrefaction conditions. The study concludes that the torrefaction process of these biomass has to be optimized based on the type of the biomass in order to offset the mass loss of these materials through the process and increase the energy value of the solid product.     

聚合条件对DMC催化PO聚合反应诱导期的影响

研究了双金属氰化物催化环氧丙烷聚合反应中，温度、压力、催化剂浓度、环氧丙烷浓度、起始剂浓度等因素与反应诱导期的关系。结果表明：温度、压力、催化剂浓度、环氧丙烷浓度与诱导期成反比，而起始剂浓度与诱导期成正比。以此推测，DMC催化PO聚合的机理与传统的碱催化机理不同，首先生成的活性中间体可能是DMC与PO结合的中间体，此中间体再与起始剂作用生成聚醚多元醇，这就是DMC聚醚的不饱和度特别低的主要原因。     

丝绸之路古代纹样若干问题研究

从宏观角度讨论了丝绸之路中有关图案起源、相互交流和共同发展的若干问题,并以典型纹样来说明.其中,很多图案不仅与特定动植物有关,甚至与建筑结构有关,且不同结构和样式之间的图案,看似无关,实质也有复杂的关系.因此,反对把不同图案加以割裂和区分开来后再行研究的方法,主张综合加以考察.