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F.T. Munna Vidhya Selvanathan K. Sobayel Ghulam Muhammad Nilofar Asim Nowshad Amin Kamaruzzaman Sopian Md. Akhtaruzzaman 《Ceramics International》2021,47(8):11003-11009
In this study, dilute chemical bath deposition technique has been used to deposit CdZnS thin films on soda-lime glass substrates. The structural, morphological, optoelectronic properties of as-grown films have been investigated as a function of different Zn2+ precursor concentrations. The X-ray diffractogram of CdS thin-film reveals a peak corresponding to (002) plane with wurtzite structure, and the peak shift has been observed with the increase of the Zn2+ concentration upon formation of CdZnS thin film. From morphological studies, it has been revealed that the diluted chemical bath deposition technique provides homogeneous distribution of film on the substrate even at a lower concentration of Zn2+. Optical characterization has shown that the transparency of the film is influenced by Zn2+ concentration and when the Zn2+ concentration is varied from 0 M to 0.0256 M, bandgap values of resulting films range from 2.42 eV to 3.90 eV while. Furthermore, electrical properties have shown that with increasing zinc concentration the resistivity of the film increases. Finally, numerical simulation validates and suggests that CdZnS buffer layer with composition of 0.0032 M Zn2+ concentration would be a promising candidate in CIGS solar cell. 相似文献
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In this paper, we discuss the problem of quality control with an unreliable machine which produces defects at a rate of Λ0, per unit when in-control and a rate of Lambda; 1, when out-of-control (where Λ1 Λ 0). Every h time periods, we sample n units, count the number of defects, and (using a process based on a Shewart c-chart) test the hypothesis that the machine is in control by comparing the total number of defects to an upper control limit (UCL). More important, we introduce the concept that a buffer inventory which immediately follows the unreliable machine may reduce expected total costs. This buffer serves to delay the movement of items from the unreliable machine to the next stage of the production process. In this way, we can isolate and repair most defective items before they are embedded in a product downstream or sold to customers where repair is more costly. To search for the optimal control policy, we find bounds for n, h, and UCL; given values for these variables, we show how the optimal buffer size can be determined directly. Numerical results illustrate the magnitude of potential savings. 相似文献
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Asim Muhammad Nabeel Ghani Muhammad Usman Ibrahim Muhammad Ali Mahmood Waqar Dengel Andreas Ahmed Sheraz 《Neural computing & applications》2021,33(11):5437-5469
Neural Computing and Applications - In order to provide benchmark performance for Urdu text document classification, the contribution of this paper is manifold. First, it provides a publicly... 相似文献
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Epidemiological studies suggest the existence of a strong relationship between the incidence of prostatic cancer and the intake
of dietary lipids in humans. However, very little information is available on intracellular fatty acid metabolism in human
prostatic tissue. The objective of this study was to identify and subsequently characterize a fatty acid binding protein of
human prostatic tissue. A fatty acid binding protein (FABP) was purified and characterized from human prostatic tissue. The
purified FABP had an apparent molecular mass of 15.0±1.0 kDa as averaged from three different methods, sodium dodecylsulfate-polyacrylamide
gel electrophoresis (SDS-PAGE), gel filtration and amino acid analysis. The pI value of the protein was determined to be 6.8.
Scatchard analysis of fatty acid binding to the purified FABP from malignant prostatic tissue showed a Kd value of 0.53±0.02
μM for arachidonic acid (n=5). The Kd values of FABP purified from benign prostatic tissue were 0.57±0.02 μM for oleic acid
and 0.51±0.04 μM for arachidonic acid (n=5). Fatty acid analysis revealed that the level of endogenously bound arachidonic
acid was about 2.5-fold higher in FABP from malignant than from benign tissue. In addition, both malignant and benign tissues
contained the same concentration of FABP. The concentrations of FABP in malignant and benign tissues were 19.2±1.8 and 21.4±2.1
μg per mg of total cytosolic protein, respectively. Characterization based on amino acid composition, isoelectric point and
fluorescence with dansyl undecanoic acid suggests that the FABP may not be of the heart type, but is rather more closely related
to the liver type. As malignant prostatic tissue produces more PGE2 compared to benign tissue, our data suggest that FABP may help enhancing the synthesis of the prostaglandin in malignant
tissue by facilitating arachidonic acid transport.
A preliminary account of this work was presented at the Biochemical Society Meeting, London, December 16–18, 1991, and published
as an abstract (Ref. 1). 相似文献
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Simultaneous surface modification by 3‐chloropropyl and methyl groups on the same Si atoms resulted in hydrophobic and highly
ordered mesoporous silica with a very high surface area. 13C and 29Si MAS NMR spectra indicate homogeneous grafting of chloropropyl and methyl groups in the silica matrix and this organically
modified Ti‐MCM‐41 shows outstanding catalytic performance in the epoxidation of cyclododecene using tert‐butyl hydroperoxide
as oxidant.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献