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1.
Refined palm olein was dry fractionated via three different cooling programs on laboratory-scale fractionation equipment. The enrichment and depletion of the main triacylglycerols in the liquid and solid phase was plotted as a function of the crystallization degree of the oil. It was shown that for the given conditions and palm olein composition, the initial crystals mainly consisted of PPP, diacylglycerols, POP and PLP. At higher crystallization degrees, a sharp viscosity increase in the crystal suspension was primarily related to an obvious decrease of POP but also of POS in the recovered superolein, while the general crystallization rate of the system remained unchanged. Rather than a change in crystallization rate of POP, a change in the ratio between the crystallizing monounsaturated triacylglycerols is linked with the high viscosity of the crystal slurry. For a comparable degree of crystallization, the superolein of the more viscous crystal slurry, obtained through a membrane press filtration up to 15 bar, was more unsaturated than the superolein filtered from the less viscous slurry. Consequently, the high unsaturation in the corresponding soft palm mid fraction is only the result of an incomplete phase separation, and not due to an increased intersolubility of unsaturated triacylglycerols in the crystals.  相似文献   
2.
A polygonP is said to be apalm polygon if there exists a pointxP such that the Euclidean shortest path fromx to any pointyP makes only left turns or only right turns. The set of all such pointsx is called thepalm kernel. In this paper we propose an O(E) time algorithm for recognizing a palm polygonP, whereE is the size of the visibility graph ofP. The algorithm recognizes the given polygonP as a palm polygon by computing the palm kernel ofP. If the palm kernel is not empty,P is a palm polygon.The extended abstract of this paper was reported at the Second Canadian Conference in Computational Geometry, pp. 246–251, 1990  相似文献   
3.
针对复杂掌纹纹线难以分割、有效性低的问题,提出一种基于二阶段小波多分辨率分析的掌纹分割算法.该方法首先利用小波多分辨率分析高频子图的候选子区域,对得到的相似掌纹纹线集合进行合并;接着对合并相似区域的集合和二值化集合求交集得到融合图像;最后利用区域生长法和形态学去噪得到掌纹主要纹理特征.实验结果表明,该方法不仅能有效地剔除复杂掌纹的噪声,而且能准确提取掌纹特征,从而达到准确识别的目的.  相似文献   
4.
随着Palm使用的越来越广泛,人们经常要用它直接与远程计算机交换数据,例如证券报价,文章通过研究,开发了它们之间的通信方法及其典型程序,利用WinSock网络编程接口和TCP/IP互连协议,通过Internet实现资料传送,包括数据的基本结构,发送与接收的基本处理过程及代码.  相似文献   
5.
An improved gas chromatography method for the simultaneous separation of 52 fatty acids (FAs) has been developed. For both oleic acid and linoleic acid, a good resolution was achieved for their positional and geometrical (cis/trans) isomers. This method was validated to be precise, accurate and sensitive. With this method, the FAs profiles in palm oil and chicken fillets were analyzed. In general, small changes were observed in the composition of FAs and formation of trans isomers after 8 h frying at the temperature lower than 200 °C. However, with extreme deep-frying process, the thermal degradation and TFAs formation in frying oil increased in direct proportion to frying temperature and time. Moreover, the FAs composition of fried chicken fillets was found to be mostly in correspondence with that of the frying oil, which might be due to the oil absorption or interaction between the frying oils and frying materials.  相似文献   
6.
The lack of technology adoption has been mentioned as a source of lack of inclusive participation of low income groups in economic activities leading to income disparity in developing countries. The study utilized an input-process-output framework to develop a set of indicators to inform the development of policies and practices to ensure the participation of low income groups in economic activities. The input element consists of technology adoption influencing factors such as socio-economic characteristics and innovating units and institutions that provide support for innovation activities. The process and output elements consist of the level of technology adoption in production processes and productivity measures respectively. Focusing on small-scale oil palm fruit processors in Nigeria, the study revealed that inadequate funding of the input processes lead to inadequate technology adoption in specific unit operations of palm oil production. Utilising selected physicochemical properties of palm oil as indicators of productivity, the samples of palm oil assessed were found to be unsuitable for industrial use and may limit the processors from participating in formal sectors of palm oil production. The study recommends policy levers that will enhance input factors through adequate funding to improve the technological base of the small-scale oil palm fruit processing.  相似文献   
7.
Modern transportation nowadays has evolved into an important economic activity for human civilisation. Even though various alternative energy solutions have been put forward to reduce the dependency on fossil fuels, biofuels remain one of the few options which are capable of replacing the roles of fossil fuels in transportation sector without suffering from major economic losses. Malaysia with a huge supply of palm oil for biofuels production is intended to implement mandatory biodiesel blends in its transportation sector in 2011 in order to achieve its carbon reduction commitment towards a more sustainable development. This implementation was originally targeted to start in 2009 but had to be postponed due to several obstacles such as expensive cost, lack of sufficient infrastructure and low public demand. On the other hand, Japan is also trying to fulfil its carbon reduction obligation as outlined under Kyoto Protocol with the usage of biofuels to replace fossil fuels in the transportation sector. However, it lacks sufficient biofuels supply to support its high transportation energy demand. In this case study, the mutual cooperation between Malaysia and Japan in the implementation of biofuels in transportation sector will be studied and analysed in order to overcome the challenges presented in both countries. It is hope to ascertain potential cooperation opportunities amongst those two countries to promote biofuels energy as Malaysia is rich in natural resources whilst Japan has the relevant expertise and technology. It is believed that the strengths from one country can help to cover for the weaknesses from the other and vice versa via closer bilateral partnership which will be extremely crucial when dealing with global energy issues. Ultimately, it is hope that this case study will enable both Malaysian and Japanese government to achieve their renewable energy target in domestic transportation sector.  相似文献   
8.
Palm oil mill effluent (POME) is a wastewater effluent that is generated from palm oil milling. Treatment of POME, especially using biological treatment methods, is a challenge as it contains high amounts of organic and sulfur compounds, and it is highly acidic. In this research, the effects of zero-valent iron (ZVI) on the enhancement of methane production from POME via anaerobic digestion were investigated. Furthermore, to identify the reactor operation modes that were suitable for the addition of ZVI, anaerobic digestion of POME was tested in three reaction configurations: batch reactor, fed-batch reactor, and continuous stirred-tank reactor (CSTR). In the batch mode, where acidic POME was fed with 16 g/L of ZVI dose just once, methane production increased by 74%. However, as the oxidation of ZVI under anaerobic conditions led to the production of hydroxyl ions, the pH of the medium continuously increased from approximately 7 to 9, which is not suitable for methanogenesis. In the fed-batch mode that involved intermittent feeding of acidic POME, the pH of the culture media was maintained at 6.8. This is because the extra hydroxyl ions generated from the oxidation reaction of ZVI tended to neutralize the acids in the feeding substrate. In addition, ZVI promoted the production of methane from POME and increased the average methane content in biogas from 62% to 76%. In the CSTR mode, which involved continuous feeding of acidic POME, ZVI increased methane production by 86% (from 1.79 to 3.32 L/day), methane content in biogas from 60 to 75%, and total chemical oxygen demand (tCOD) removal efficiency from 78 to 89 to 88–95%. Thus, the addition of ZVI can be a potential strategy for in-situ methane enrichment of biogas by anaerobic digestion of POME. This is because ZVI acts as a buffer for acid generation and provides extra electrons, ferrous ions, and ferric ions, which promote key microbial activities in the anaerobic digestion process.  相似文献   
9.
Bio-hydrogenated diesel (BHD) is a second generation biofuel that can be produced from vegetable oil and hydrogen via hydroprocessing. BHD is considered as one of alternative and renewable energy. This work presents evaluation of environmental impacts of BHD produced from palm fatty acid distillate (PFAD) compared to fatty acid methyl ester (FAME). Greenhouse gas emission, energy consumption, and overall environmental impacts are assessed. System boundary is from palm oil cultivation to BHD production. The functional unit is defined as 1 kg of fuel produced at the plant. The results indicate that energy consumption of BHD-PFAD is 1.18 times higher than that of BHD-FAME, while giving GHG emission 13.56 times lower than that of BHD-FAME. The results of overall environmental impacts indicated that BHD-PFAD was 3.58 greater than that of BHD-FAME.  相似文献   
10.
Microbial electrolysis cells (MECs) are a new bio-electrochemical method for converting organic matter to hydrogen gas (H2). Palm oil mill effluent (POME) is hazardous wastewater that is mostly formed during the crude oil extraction process in the palm oil industry. In the present study, POME was used in the MEC system for hydrogen generation as a feasible treatment technology. To enhance biohydrogen generation from POME in the MEC, an empirical model was generated using response surface methodology (RSM). A central composite design (CCD) was utilized to perform twenty experimental runs of MEC given three important variables, namely incubation temperature, initial pH, and influent dilution rate. Experimental results from CCD showed that an average value of 1.16 m3 H2/m3 d for maximum hydrogen production rate (HPR) was produced. A second-order polynomial model was adjusted to the experimental results from CCD. The regression model showed that the quadratic term of all variables tested had a highly significant effect (P < 0.01) on maximum HPR as a defined response. The analysis of the empirical model revealed that the optimal conditions for maximum HPR were incubation temperature, initial pH, and influent dilution rate of 30.23 °C, 6.63, and 50.71%, respectively. Generated regression model predicted a maximum HPR of 1.1659 m3 H2/m3 d could be generated under optimum conditions. Confirmation experimentation was conducted in the optimal conditions determined. Experimental results of the validation test showed that a maximum HPR of 1.1747 m3 H2/m3 d was produced.  相似文献   
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