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1.
Phuong-Anh Ngoc Doan Tzyi-Horng Tan Lee Fong Siow Beng Ti Tey Eng Seng Chan Teck-Kim Tang Nur Azwani Abdul Karim Eng-Tong Phuah Yee-Ying Lee 《Journal of the American Oil Chemists' Society》2021,98(6):609-620
Palm fatty acid distillate (PFAD) is a rich source of vitamin E. As compared to other vegetable oil, PFAD has higher tocotrienol (70–80%) over tocopherol content, which makes it a valuable source for vitamin E extraction. Current vitamin E extraction methods are not sustainable due to the intensive usage of chemical and high operational cost. Hence, the present study investigated for the first time using dry fractionation process as a green and economical pretreatment method for separating solid fraction (stearin) and liquid fraction (olein) in order to concentrate vitamin E from PFAD in olein fraction. We examined the dry fractionation conditions: crystallization ending temperature (36–44 °C), cooling rate (0.3 and 1.5°C min−1), stirring speed (20–125 rpm), and holding time (0–60 min) on the composition of unsaturated and saturated fatty acids as well as vitamin E content in liquid fraction (olein) and solid fraction (stearin) using gas chromatography and high performance liquid chromatography, respectively. In most of these conditions, vitamin E was ultimately higher in olein fraction as compared to stearin fraction, which is correlated with the high degree of unsaturation. Under a cooling rate of 0.3°C min−1, 90 rpm stirring speed, and ending crystallization of 38 °C, the highest vitamin E rich olein fraction was attained with 1479 ± 10.51 ppm in 50 g olein fraction as compared to 1366 ± 7.94 ppm in 500 g of unfractionated PFAD. 相似文献
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I. V. Bogachev A. V. Levenets E. U. Chye 《Optoelectronics, Instrumentation and Data Processing》2018,54(3):256-261
Bit space representation of measurement data is considered. A method and its associated algorithm for reversible geometric compression of measurement data frames are proposed. The algorithm is based on the conversion of a data frame into bit form with subsequent mapping onto a plane and partition into strictly homogeneous regions. Experimental results are presented showing that the proposed algorithm provides high overall compression efficiency.. 相似文献
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Minds and Machines - To address the rising concern that algorithmic decision-making may reinforce discriminatory biases, researchers have proposed many notions of fairness and corresponding... 相似文献
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E. Ja. Kipko D. Sc. Min. Eng. 《Mine Water and the Environment》1985,4(2):35-39
The paper describes the results of an experimental grouting programme carried out by the Spetstamponazhgeologia association at the Dobrogea coalfield in Bulgaria. The anticipated water inflow into a shaft at this deposit totals 8 m3/s at a pressure of 12 MPa, from a cavity size equal or exceeding 3 metres. Grouting operations made it possible to cut down water inflow by a factor of more than one thousand. The success of this investigation has enabled the author to design an exprrimental shaft sinking project through the valange formation at Dobrogea mine. 相似文献
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An experimental study was undertaken to determine the effects of administering shock loads of sucrose to a laboratory-scale anaerobic effluent treatment plant (UASB reactor) treating diluted landfill leachate. Administration of shock loads of 10 g l− sucrose caused accumulations of up to 7 g l−1 of l-lactate and the resultant acidity caused the pH value of the reactor effluent to drop from 7.2 to 4.7 which inhibited methanogenesis.Major disturbances in the composition of the biogas also occurred and, under the severest conditions, the biogas contained up to 30% (v/v) hydrogen. 相似文献
9.
H.J.C. Weighell Wh. Sch. C.Eng. M.I.M.E. M.I.P.E. 《The International journal of environmental studies》2013,70(1-4):237-242
Vehicle legislation for safety and emission control is led by the USA where half the world's cars and one‐third of the world's road deaths are found. The 1975/6 standards will cause confrontations between industry and government in the U.S.A. and have costly implications for the American people. The rest of the world is affected by what happens in the U.S.A. but for language and other reasons fragmented laws are normal with conflicting requirements for manufacturers who supply the many markets. The greatest force for harmonization of legislation may be the enlarged Common Market including, as it does, the four major European Car manufacturing countries. The Common Market Commission may displace WP 29 of the United Nations as the leading law‐making body. Type approval is the compliance system used in Europe, but the growth in scope of safety and other legislation is bringing into focus a weakness of the system which is reducing production efficiency to an alarming degree. American style self‐certification is not acceptable to European governments. 相似文献
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This paper contains the results of measured dielectric constants of leaves of two tropical crops, rubber ( Heavea brasiliensis ) and oil palm ( Elaeis guineensis ) at microwave frequency region. Using a microcomputer-based automated system consisting of a Wiltron 360B vector network analyser,measurements are conducted based on the waveguide thin sheet technique. Leaf samples are inserted within waveguide sections, and the dielectric constants are calculated from the complex reflection coefficients. The measurements cover a frequency range of 4-18GHz. In general, the dielectric constant of a leaf sample is a function of water content and frequency. Theoretical calculations from three dielectric mixing models, i.e., the Debye-Cole Dual-Dispersion dielectric model by Ulaby and Rayes, Matzler's Model and Carlson's Model are compared with the measurements. From the comparisons, the dual-dispersion model is found to show more promise in prediction of the dielectric constants, if proper physical parameters of the model, such as bound and free-water volume fractions, are used. 相似文献