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排序方式: 共有93条查询结果,搜索用时 15 毫秒
41.
Tamikazu Kume Shinpei Matsuhashi Shoji HashimotoMat Rasol Awang Hassan HamdiniHideharu Saitoh 《Radiation Physics and Chemistry》1993,42(4-6):727-730
The production of animal feeds and mushrooms from oil palm cellulosic wasres by radiation and fermentation has been investigated in order to utilize the agro-resources and to reduce the smoke pollution. The process is as follows: decontamination of microorganisms in fermentation media of empty fruit bunch of oil palm (EFB) by irradiation, inoculation of useful fungi, and subsequently production of proteins and edible mushrooms. The dose of 25 kGy was required for the sterilization of contaminating bacteria whereas the dose of 10 kGy was enough to eliminate the fungi. Among many kinds of fungi tested, C. cinereus and P. sajor-caju were selected as the most suitable microorganism for the fermentation of EFB. The protein content of the product increased to 13 % and the crude fiber content decreased to 20% after 30 days of incubation with C. cinereus at 30°C in solid state fermentation. P. sajor-caju was suitable for the mushroom production on EFB with rice bran. 相似文献
42.
Saifuddin Nomanbhay Refal Hussein Mei Yin Ong 《Green Chemistry Letters and Reviews》2018,11(2):135-157
Biodiesel being one of the most promising renewable biofuels has seen rapid increase in production capacity due to high demand for diesel replacement; along with oversupply of its by-product, crude glycerol. Developing new industrial usage for glycerol is essential to defray the cost and sustainability of biodiesel industry and to promote the biodiesel industrialization. One of the approaches is by the transformation of glycerol into a liquid, referred as bio-oil through pyrolysis technology. Bio-oils produced by pyrolysis processes can be upgraded to produce transportation fuels or for power generation. However, current state of pyrolysis technologies are still major hurdles their development with respect to its commercial applications. Recently, microwave technology has attracted considerable attention as effective method for significantly reducing reaction time, improving the yields and selectivity of target products. Hence, this review strives extensively towards addressing the application of microwave-assisted technology applied to the pyrolysis process as a way of cost-effective and operationally feasible processes to directly utilize crude glycerol. The present review will focus on the pyrolyzed liquid product (bio-oil) derived by employing the microwave-assisted pyrolysis method. This review concludes that microwave-assisted glycerol conversion technology is a promising option as an alternative method to conventional glycerol conversion technology. 相似文献
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45.
Fernando J. S. Oliveira Leonardo Vazquez Norberto P. De Campos Francisca P. de Fran?a 《Applied biochemistry and biotechnology》1996,131(1-3):727-737
Biosurfactants production by a strain of Pseudomonas aeruginosa using palm oil as a sole carbon source was investigated. The experiments were carried out in 500-mL conical flasks containing
100 mL of mineral media supplemented with palm oil as the sole carbon source. The P. aeruginosa FR strain was able to reduce surface tension of three tested inorganic media. Rotation velocities from 100 to 150 rpm provided
free-cell fermented media with the lowest surface tension of approx 33 mN/m. Emulsification index results of even 100% were
achieved when diesel was used as oil phase. Eight surface-active compounds produced by the bacterium were identified by mass
spectrometry. 相似文献
46.
基于局部灰度极小值的掌脉图像分割方法 总被引:7,自引:5,他引:2
针对手掌皮下静脉(简称掌脉)成像照度不均匀、对比度低和噪声严重,提出一种基于局部灰度极小值掌脉图像自动分割方法,回避了阈值选择,能够有效解决光照不均、对比度低、噪声严重等干扰。通过自建掌脉图库的实验结果表明,该方法除了能够有效地抑制噪声、光照不均和对比度低的影响外,与目前的掌脉分割方法相比,在掌脉提取连续性和不需要选择... 相似文献
47.
Rami K. Suleiman Wissam Iali Bassam El Ali Saviour A. Umoren 《Molecules (Basel, Switzerland)》2021,26(14)
The phytochemical analysis of the butanolic extract from the leaves of date palm of Saudi origin resulted in the isolation of three major constituents, oleanolic acid (1), vanillyl alcohol (2), and β-sitosterol-3-O-β-d-glucoside (3), which had not been isolated from this plant or previously reported. Together, compounds 1 and 2 account for 1.0% of the butanol extract, which represents 0.4% of the mass of the dried leaves. The isolation of other known compounds for this plant such as fatty acids, lutein, and sucrose was also achieved in this study. The characterization and identification of the isolated compounds were conducted on the basis of Fourier-transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR), liquid chromatography–mass spectrometry (LC–MS), and gas chromatography–mass spectrometry (GC–MS) analyses. The findings of the current study will definitely increase the knowledge about the contribution of the constituents of this plant to its well-known nutrition, corrosion inhibition, and antimicrobial properties. 相似文献
48.
Owing to the increasing reports of the harmful effects of trans and saturated fatty acids, the demand for trans- and saturated-fatty-acid-free oil and fat products is increasing among consumers. However, it is difficult to maintain the product stability and shape retention of such oil and fat products. As a result, there is a high demand in the processed oil and fat industry to develop solutions to such problems. Herein, we used molecular compound (MC) crystals in an attempt to find alternatives to trans and saturated fatty acids. The MCs used were 1,3-dioleoyl-2-palmitoyl-sn-glycerol (OPO) and 1,3-dipalmitoyl-2-oleoyl-sn-glycerol (POP)—the main components of lard and palm oil, respectively. We believe that OPO and POP can be used to obtain no-trans, low-saturation, and high-oleic-acid oil and fat products. Optimal conditions for efficient MC crystallization were examined by changing the oil and fat composition under rapid cooling conditions assuming industrial cooling process by using differential scanning calorimetry and synchrotron radiation time-resolved X-ray diffraction methods. It was concluded that the increase in OPO concentration destabilized MC formation, while the increase in POP concentration stabilized it under rapid cooling conditions. As a result, it was shown that MC crystals can be efficiently obtained by reducing the degree of POP supercooling. 相似文献
49.
M. N. Mohamad Ibrahim A. Md. Ghani N. Zakaria S. Shuib C. S. Sipaut 《Macromolecular Symposia》2008,274(1):37-42
Summary: Malaysia has over 4 million hectares of oil palm plantations that yield large amounts of empty fruit bunches (EFB) generated from palm oil milling operations. These forms of lignocellulosic residue pose an environmental hazard if their disposal is not managed in a systematic manner. One of the useful elements extracted from these EFBs is lignin. The general purpose of this study is to explore the potential uses of lignin extracted from soda black liquor (paper and pulping waste) derived from oil palm empty fruit bunches (EFB) in the formulation of a more environmentally friendly wood adhesive. In this work, the potential for replacing phenol with lignin in phenol formaldehyde resin formulation is examined. The quantity of phenol was reduced by synthesizing the resin at a lignin to phenol ratio of 1:1. The physical and chemical properties of lignin phenol formaldehyde resin (LPF) and commercial phenol formaldehyde resin (CPF) were then compared. The infrared spectrum revealed similarities in the functional groups of both LPF and CPF resins. Tensile strength comparisons between both resins revealed that the LPF resin had a higher bonding strength (11.60 MPa more in term of allowable maximum load). In addition, the kinematics viscosity test showed that the LPF resin had lower kinematic viscosity than the CPF resin after 21 days of storage. Finally, the scanning electron microscope images for both resins showed similarities in terms of penetration into wood vessels. 相似文献
50.
通过对掌形图像采用小波模极大值算法去除噪声,建立了极大值矩阵及跟踪矩阵,分辨出小波系数的信噪属性,剔除了噪声部分对应的小波系数极大值,从而抑制了噪声污染.在阈值设置问题上,采用改进的自适应阈值,克服单一阈值不能在每级尺度上将信号与噪声作最大分离的缺点,该方法不仅有效去除噪声,同时保持了图像边缘细节,具有良好的消除噪声的效果. 相似文献