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Jülide Hazal Türkcan Hüseyin Elçiçek Oğuz Kaan Özdemir 《International Journal of Hydrogen Energy》2021,46(11):7903-7911
Hydrogen production through hydrolysis of sodium borohydride (NaBH4) by using metal catalysts is promising for fuel cell applications. Nickel (Ni) and its alloys are favorable due to their high catalytic activity, relatively low cost and availability. In present study, the effects of temperature, pH, reduction rate and reducing agent concentration, which significantly affect the catalyst performance, were investigated using the response surface methodology (RSM). A mathematical model was derived according to results which were obtained from four-level orthogonal Taguchi L16 (44) experimental design used for the optimization of multiple parameters in the process. From the RSM analyses, that compatible with the predicted experimental results, maximum hydrogen generation rate (HGR) 49.81 L min?1 gcat?1 was obtained temperature of 278.12 K, pH of 5.52, reducing agent concentration of 85.96 NaBH4.water?1 and reduction rate of 6.82 mL min?1. Analysis of variance reveals that both pH and rate of reduction have significant effect than the temperature on the HGR. 相似文献
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This study describes a numerical projection of pre- and post-retrofitted conditions of telecommunication poles subjected to seismic hazards. The absence of explicit guidelines for the rehabilitation of existing poles motivated the investigation of the effectiveness of steel jacketing for the retrofitting of self-supporting steel and reinforced concrete (RC) telecommunication poles. Effects of mast flexibility, variable damping on dynamic response, and significance of period on base shear amplification were investigated. The overall effectiveness of retrofitting against base excitation was assessed for RC and steel poles through the application of modal analyses and response spectrum approach based on a set of strong motion accelerograms recorded during the 1994 Northridge earthquake. Based on a serviceability approach, the analysis of results shows effectiveness of the steel jacketing in increasing load carrying capacity of the poles by enabling stress redistribution. 相似文献
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<正>阿尔斯特图书馆和表演艺术学院坐落在比利时阿尔斯特,由一栋8000m~2的砖结构建筑和一栋引人注目的 19世纪后期的历史建筑组成。项目的名称为"乌托邦",与托马斯莫尔的著作《乌托邦》同名,这本书是由阿尔斯特市民德克马滕斯首先出版。 相似文献
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Abhijit Brahme Yauheni Staraselski Kaan Inal Raja K. Mishra 《Metallurgical and Materials Transactions A》2012,43(13):5298-5307
A new method for analyzing microstructure is proposed to evaluate the long-range dependence of texture. The proposed method calculates the average disorientation as a function of distance between data points as measured by electron backscatter diffraction patterns. This method gives a measure of clustering of texture and is used to evaluate accurately the effective grain size. This procedure in conjunction with Information theory is used to estimate a representative scan size for various materials. Analyses show that the optimal scan size depends on grain morphology and crystallographic texture. The results also indicate that on an average the optimal scan size needs to be 10 times the effective grain size. 相似文献
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Burçak Işçi Hatice Kalkan Yildirim Ahmet Altindisli 《Journal of the Institute of Brewing》2014,120(3):238-243
The quality of wine depends on many factors. One of the most important is the selection of appropriate and defined grape varieties. The analysis of phenolic compounds, amino acids, trace elements and isotopes of wines, used for the identification of grapes varieties, is not sufficient and requires a lengthy analysis period. The development of molecular techniques such as restriction fragment length polymorphism, random amplified polymorphic DNA and microsatellites provides opportunities for the differentiation of grape varieties. In this regard, the use of DNA extracted from must and wine appears to be a good marker for the identification of grape varieties used in wine production. In this study, DNA was extracted from grape, leaf, must and wine samples of Vitis vinifera L. cv. Cabernet Sauvignon, Merlot and Sauvignon Blanc origin and examined using different extraction methods. Of the DNA extraction methods tested, the method using absorption at 260/280 nm (with values of 0.19 and 1.92) was considered the method of choice. Copyright © 2014 The Institute of Brewing & Distilling 相似文献
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Hatice Kalkan Yıldırım Burçak İşçi Ahmet Altındişli 《Journal of the Institute of Brewing》2015,121(4):636-641
The aim of the study was to investigate the quality of blended wines produced from Vitis vinifera L. Cabernet Sauvignon, Merlot and Sauvignon blanc grapes. Wines were processed according to accepted conventional methods for white and red wines. Blended wines were produced with different ranges (25, 50, 75 and 100%) of Cabernet Sauvignon, Merlot and Sauvignon blanc wines. Produced wines were evaluated for total phenols (mg/L), total tartaric esters (mg/L caffeic acid), total flavonols (mg/L quercetin), chemometric parameters such as D280%, D420%, D520%, D620%, dA%, CD%, T, CI%, R%, Y% and B%, CIELAB parameters, protein, total and volatile acidity. Analyses on an n‐dimensional scale demonstrated the relationships among the wines of different grape origins and different blending ratios. On the basis of these differences, two main groups were plotted using principal component analysis and cluster analysis. The results demonstrate the possibilities of optimizing wines on the basis of defined parameters. Copyright © 2015 The Institute of Brewing & Distilling 相似文献