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排序方式: 共有3038条查询结果,搜索用时 15 毫秒
1.
Chun Yang Yin Sharifah Aishah Syed Abdul KadirYing Pei Lim Sharifah Nawirah Syed-AriffinZurinawati Zamzuri 《Fuel Processing Technology》2008
Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material. 相似文献
2.
Abdul Aleaf 《电子产品世界》2008,15(12)
消费者对于移动多媒体的需求是毫无疑问的,满足这些需求的技术已经开发成功,对于设计人员而言,剩下的问题就是如何利用这些技术,并将成功的产品带入市场。本文将讨论如何减省移动多媒体设备内关键元件的功耗,此外也会对现今移动多媒体设备设计人员所面对的工程挑战作出概括的分析,并就目前及新涌现的硅技术,提出可克服这些工程挑战的解决方案。 相似文献
3.
This study investigates the dynamic representation of a group of induction motors by one or more equivalent motors. The unknown parameters of the equivalent are estimated through a weighted-least-squares procedure. Verification of simulated results with experimental ones suggests that a fifth order dynamic model of the aggregate with a ninth order parameter model is appropriate. The least squares technique was found to provide good convergence characteristics subject to satisfaction of the following conditions good initial estimate of the parameters, proper selection of acceleration factors and homogenity of the motor group. 相似文献
4.
Uma Maheswar Rao S. S. M. S. Abdul Majeed C. Venkataseshaiah R. Sarathi 《Bulletin of Materials Science》2002,25(6):473-475
In the present work, tracking phenomena has been studied with silicone rubber material under the a.c. and d.c. voltages following
IEC-587 standards. The surface condition of the tracked zone was analysed using wide angle X-ray diffraction (WAXD) and thermogravimetric
differential thermal analysis (TG-DTA) studies. The tracking time was different for a.c. and d.c. voltages. 相似文献
5.
6.
Abdul S Chaudhry 《Journal of the science of food and agriculture》2007,87(14):2617-2624
BACKGROUND: Two factorial studies compared enzymic and in sacco methods to estimate degradation of ruminant foods. Enzyme degradation (in vitro = enzyme) was determined from the release of leucine‐equivalent amino acid (LA) crude protein (CP) from sunflower meal (SF), maize gluten meal (MG), distillers' dark grain (DG) and field beans (FB) after their separate incubations with Streptomyces griseus enzyme for 0–24 h. In sacco crude protein (CP) degradation of these foods was estimated during washing (0 h) and rumen incubations in fistulated cows for 2–24 h. The LA data were expressed as g LA per either kg of CP (LACP) or acid‐hydrolysable LA (HLA) of each food and compared with in sacco data. RESULTS: These methods showed comparable degradation with time (P < 0.01). The in sacco and HLA were greater than LACP for all foods except MG where in sacco value was either lower or equal to LACP depending upon the incubation time (P > 0.05 or P < 0.05). Conversely, HLA was significantly (P < 0.01) greater than LACP from 2 h onwards. At 0 h, in sacco values were significantly greater than those of enzyme for SF, DG and FB (P < 0.05) but not for MG. The foods differed significantly for degradation constants (a, b, c) in each method (P < 0.05). CONCLUSIONS: Despite variations between in sacco and enzyme estimates for different foods, the relationships between these estimates suggest that the HLA enzyme method has the potential to estimate food degradation. Copyright © 2007 Society of Chemical Industry 相似文献
7.
Ali Hussein F. M. Khan Abdul Manan Baek Hangyeol Shin Buhyun Kim Youngshik 《Microsystem Technologies》2021,27(6):2481-2492
Microsystem Technologies - In this research a biologically inspired finger-like mechanism similar to human musculoskeletal system is developed based on Shape Memory Alloys (SMAs). SMA actuators are... 相似文献
8.
Zamli Kamal Z. Kader Abdul Din Fakhrud Alhadawi Hussam S. 《Neural computing & applications》2021,33(23):16641-16658
Neural Computing and Applications - Cryptography often involves substituting (and converting) the secret information into dummy data so that it could reach the desired destination without leakage.... 相似文献
9.
Kader Md. Abdul Zamli Kamal Z. Ahmed Bestoun S. 《Neural computing & applications》2021,33(23):15933-15953
Neural Computing and Applications - Emperor Penguin Optimizer (EPO) is a recently developed metaheuristic algorithm to solve general optimization problems. The main strength of EPO is twofold.... 相似文献
10.
Prof. Dr. S. Darwish Dr. M. W. Khalil Dr. M. A. Abdel Rahim Porf. Dr. I. A. Ammar 《Materialwissenschaft und Werkstofftechnik》1989,20(9):299-308
A study on the value metal character of Zr in 0.1 M solutions of H2SO4, HNO3, and H3PO4 has been performed using the anode potential as the primary variable in galvanostatic, potentiostatic, and capacity measurements. A method of surface pre-treatment, which suppresses both O2 evolution and metal dissolution, has been described. Kinetic parameters of oxide growth have been calculated. The results indicate that:
- (i) the high field approximation is applicable following an exponential law, and
- (ii) the height and activation distance of the energy barrier for ion transport through the oxide phase (Verwey model) are the same three acids.