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Mohammad Shakirullah Imtiaz Ahmad Habibur Rahman M. Arsala Khan M. Ishaq Amjad Ali Shah 《中国化学会会志》2006,53(5):1059-1066
This paper demonstrates the spectral analysis of some distillates obtained from asphalt cracking in the presence of a conventional expensive catalyst, i.e., HZSM‐5, and local cheap and readily available clay, i.e., UTIMAC. Each distillate was fractionated into pentane soluble (PI) and pentane insoluble (PI) fractions based on solubility in n, pentane. Both PS and PI obtained in the case of HZSM‐5 and UTIMAC were analyzed by 1H‐NMR spectrophotometry using CDCl3 as dissolving solvent and tetramethylsilane (TMS) as internal standard. It is evident from the profiles that both catalysts caused the generation of some peaks ascribed to methylene and methene configurations in the aliphatic region. Bands corresponding to aromatic configurations were also generated. The results indicate that the cheap local catalyst used has comparable suitability with the conventional expensive catalyst in terms of asphalt cracking. 相似文献
13.
Amjad Alipanah Shahrokh Esmaeili 《Journal of Computational and Applied Mathematics》2011,235(18):5342-5347
In this paper, we introduce a numerical method for the solution of two-dimensional Fredholm integral equations. The method is based on interpolation by Gaussian radial basis function based on Legendre-Gauss-Lobatto nodes and weights. Numerical examples are presented and results are compared with the analytical solution to demonstrate the validity and applicability of the method. 相似文献
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Disposal of untreated industrial effluents is drastically deteriorating the quality of underground water. Research work has been conducted to analyze the effect of disposal of urea plant effluent on the quality of ground water of the District Mianwali Daudkhail, Pakistan. For this purpose the effluent and ground water samples were analyzed for pH, TDS, TSS, Cl, F, COD, BOD, Fe, Zn, Pb, Cu, Cr, Cd, Mn, and As. Results obtained were compared with WHO and NEQS standards for drinking and effluent emission limits, respectively. Moreover, effluent samples were also evaluated for irrigation purposes and results compared with criteria recommended for irrigation water. Results showed though the effluents were according to the standards given by National Environmental Quality Standards (NEQS) for liquid emission and fit for irrigation purposes, the quality of underground water was below standard due to having a higher quantity of total dissolved solids than permissible. 相似文献
16.
Thin-film transistors (TFTs) fabricated in polysilicon films deposited by plasma enhanced chemical vapor deposition (PECVD)
were characterized. The transistors were fabricated using a low temperature process (i.e., <- 700° C). The characteristics of the devices were found to improve as the deposition temperature of the polysilicon film
increased. The best characteristics (μ
FE of 15 cm2/V
s andV
TH of 2.2V) were measured in the devices fabricated in the film deposited at 700° C. The devices fabricated in the PECVD polysilicon
films were compared to those fabricated in polysilicon films deposited by thermal CVD in the same reactor in order to decouple
the effect of the plasma. A coplanar electrode structure TFT with adequate characteristics (μ
FE of 8 cm2/V
s) was also demonstrated in the PECVD polysilicon films. 相似文献
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Nerve-muscle preparations of Sprague Dawley rats were exposed to low dosage ultrasound. The objectives were to measure the velocity of propagation and attenuation of ultrasonic energy in both the relaxed and contracted states. A tension-measuring system and associated ultrasonic instrumentation were designed to measure the tension developed in stimulated muscle and its corresponding acoustic parameters, ie the attenuation coefficient, (db cm-1) and the velocity of propagation, c (ms-1). Each test was performed at ultrasonic frequencies 3.1, 5.35, and 7.68 MHz and with the preparation maintained at 23 ± 0.5° C. Attenuation of ultrasonic energy was observed to increase by 10 ± 0.5% in the active state from its value in the relaxed state. The relation between the attenuation and the acoustic frequency was found to be approximately linear over the frequency range tested. The velocity of propagation in the active state did not change appreciably from its value in the relaxed state and was observed to be independent of the acoustic frequency in the range used. 相似文献
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Shapour Heidarkhani Massimiliano Ferrara Giuseppe Caristi Amjad Salari 《Acta Appl Math》2018,156(1):133-157
This article is concerned with the multiplicity results of the solutions for a Kirchhoff-type three-point boundary value problem. The method observed here is according to variational methods and critical point theory. In fact, through a consequence of the local minimum theorem due Bonanno and mountain pass theorem, we look into the existence results for our problem under algebraic conditions with the classical Ambrosetti-Rabinowitz (AR) condition on the nonlinear term. Furthermore, by combining two algebraic conditions on the nonlinear term, employing two consequences of the local minimum theorem due Bonanno we guarantee the existence of two solutions, and applying the mountain pass theorem given by Pucci and Serrin we establish the existence of third solution for the problem. 相似文献