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31.
Bahram Hemmateenejad Ghodratollah Absalan Mohsen Nekoeinia Fatemeh Esfandiyari 《Chemometrics and Intelligent Laboratory Systems》2010,102(1):35-186
Rank deficiency is the major problem associated with the chemometrics modeling of the second-order chemical reactions of the form of A + B → C. In this article, the application of the hard-soft-net analyte signal (HS-NAS), as a newly proposed method in our research group, is described for modeling of second-order reactions. This combined hard-soft method is based on the net analyte signal (NAS) concept, which is defined as a part of total signal that is directly related to the concentration of the component of interest. Therefore, concentration changes versus time can be obtained by calculating NAS for any chemical species involved in the reaction without requiring any pure component spectra or extra runs. The power of the method was verified by applying it to the resolution of simulated data sets containing noises added at different levels. The resolution of the second-order reaction between amoxicillin and 1, 2-naphthoqoinone was also tested as a real chemical system. 相似文献
32.
Empirical evaluation of river basin sustainability affected by inter‐basin water transfer using composite indicators 下载免费PDF全文
Maryam Kefayati Bahram Saghafian Azadeh Ahmadi Hossein Babazadeh 《Water and Environment Journal》2018,32(1):104-111
In this study, a practical approach to evaluate the sustainability of river basins subjected to an inter‐basin water transfer project is developed. Selection of appropriate evaluation indicators is pivotal to such approach. To make use of huge amount of data, composite indicators of sustainability (CIS) should be utilised. The proposed approach relies on 15 sustainability indicators (SI) that cover three major criteria namely (economic, social and environmental), and aggregates them into eight different types of sustainability indices for a more robust outcome. Two scenarios were considered within the source and recipient basins. Furthermore, multivariate principal component analysis (PCA) was applied to determine principal and non‐principal indicators for the two river basins. The ability of CIS and PCA methods were verified via correlation and simple regression methods respectively. The results demonstrated that inter‐basin water transfer may improve sustainability, provided that a proper water resource management is enforced. 相似文献
33.
Bahram Behnajady Amin Babaeidehkordi Javad Moghaddam 《Metallurgical and Materials Transactions B》2014,45(2):562-567
This research is part of a continuing effort to leach zinc from zinc cathode melting furnace slags (ZCMFSs) to produce zinc oxide. The slag with an assay of 68.05 pct Zn was used in ammonium chloride leaching for zinc extraction. In this paper, the effects of influential factors on extraction efficiency of Zn from a ZCMFS were investigated. The Taguchi’s method based on orthogonal array (OA) design has been used to arrange the experimental runs in order to maximize zinc extraction from a slag. The softwares named Excel and Design-Expert 7 have been used to design experiments and subsequent analysis. OA L 25 (55) consisting of five parameters, each with five levels, was employed to evaluate the effects of reaction time (t = 10, 30, 50, 70, 90 minutes), reaction temperature [T = 313, 323, 333, 343, 353 (40, 50, 60, 70, 80) K (°C)], pulp density (S/L = 20, 40, 60, 80, 100 g/L), stirring speed (R = 300, 400, 500, 600, 700 rpm), and ammonium chloride concentration (C = 10, 15, 20, 25, 30 pctwt), on zinc extraction percent. Statistical analysis, ANOVA, was also employed to determine the relationship between experimental conditions and yield levels. The results showed that the significant parameters affecting leaching of slag were ammonium chloride concentration and pulp density, and increasing pulp density reduced leaching efficiency of zinc. However, increasing ammonium chloride concentration promoted the extraction of zinc. The optimum conditions for this study were found to be t 4: 70 minutes, T 5: 353 K (80 °C), (S/L)2: 40 g/L, R 3: 500 rpm, and C 4: 25 pctwt. Under these conditions, the dissolution percentage of Zn in ammonium chloride media was 94.61 pct. 相似文献
34.
Hamed Bazrafshan Razieh Shajareh Touba Zahra Alipour Tesieh Saeideh Dabirnia Bahram Nasernejad 《Chemical Engineering Communications》2017,204(10):1105-1112
In this study, Co3O4 nanosheets were synthesized through hydrothermal method using cobalt nitrate hexahydrate. X-ray diffraction, diffuse reflectance spectra, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and field emission scanning electron microscopy were applied to investigate the properties of as-synthesized samples. Ultimately, the electrochemical and photoelectrochemical properties were evaluated by Mott–Schottky analysis and measuring photoconversion efficiency of Co3O4 nanosheets. The results indicated that Co3O4 nanosheets exhibited a maximum efficiency of 0.92% for water electrolysis under simulated 1.5 global sunlight air mass, which further suggests the excellent potential of Co3O4 nanosheets for application in hydrogen generation through photocatalytic water splitting. 相似文献
35.
Mohammad Masoumi Bahram Sami Kashkooli Mohammad Javad Monem Hossein Montaseri 《Water Resources Management》2016,30(14):5051-5063
In the context of water as an economic good, from the use of water, one can derive a value, which can be affected by the reliability of supply. On-demand irrigation systems provide valuable water to skilled farmers who have the capacity to maximize economic value of water. In this study, simultaneous optimization of on-demand irrigation network layout and pipe sizes is considered taking into account both investment and annual energy costs. The optimization problem is formulated as a problem of searching for the upstream head value, which minimizes the total cost (investment and energy costs) of the system. The investment and annual energy costs are obtained in two separate phases. Max–Min ant system (MMAS) algorithm is used to obtain the minimum cost design considering layout and pipe diameters of the network simultaneously. Clement methodology is used to determine flow rates of pipelines at the peak period of irrigation requirements. The applicability of the proposed method is showed by re-designing a real world example from literature. 相似文献
36.
Hossein Alinouri Fakhrodin Ahmadi Danesh Seyed Bahram Beheshti‐Aval 《The Structural Design of Tall and Special Buildings》2013,22(17):1296-1309
In recent earthquakes, many buildings have been damaged due to the soft‐storey mechanism failure. The seismic design codes for buildings do not contain enough criteria to predict the real displacement of such buildings. This paper focuses on evaluating the nonlinear displacement of buildings that fail in soft‐storey mechanism form. Results show that the nonlinear static procedure with coefficient method, which is described in Chapter 3 of ASCE/SEI 41‐06, does not have sufficient accuracy for estimation of structure displacement demand in such buildings. In this paper, the coefficient methodology is used for evaluating the target displacement for 5‐storey, 8‐storey and 15‐storey special moment resisting steel frames. For this purpose, dynamic nonlinear time‐history analysis has been applied for the mentioned structures having a soft‐storey mechanism failure form. The numerical results of storey displacement and interstorey drift were compared with those values obtained from the coefficient method described in Chapter 3 of ASCE/SEI 41‐06. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
37.
38.
Bertaux N Frauel Y Réfrégier P Javidi B 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(12):2283-2291
We propose a method based on the maximum-likelihood technique for removing speckle patterns that plague coherent images. The proposed method is designed for images whose gray levels vary continuously in space. The image model is based on a lattice of nodes corresponding to vertices of triangles in which the gray level of each pixel is produced by linear interpolation. A constraint on isoline gray levels is introduced to regularize the solution. 相似文献
39.
Bahram GhaemiGaoling Zhao Guangtao JieHaidong Xi Xiuming LiJianxun Wang Gaorong Han 《Optical Materials》2011,33(6):827-830
Transparent Al2O3-SiO2-ZnO-R2O glass ceramics were fabricated by melting method. The effects of the different kind of alkali ions on the formation of the transparent glass ceramic were studied. X-ray diffraction and high resolution transmission electron microscope were measured to study the microstructure of the samples. The results showed that, transparent glass ceramic including ZnO quantum dots was obtained after heat treatment from 700 °C to 800 °C for the sample containing K2O. While glasses containing Li2O and Na2O were opal after heat treatment. Photoluminescence properties of the K2O contained samples were studied. It was found that the photoluminescence peak shifted to longer wavelength when the heat treatment temperature and time increased, which can be ascribed to the increasing of ZnO quantum dots size. 相似文献
40.
Ezzatallah Baloui Jamkhaneh Bahram Sadeghpour-Gildeh Gholamhossein Yari 《Structural and Multidisciplinary Optimization》2011,43(4):555-560
In this paper we have designed an acceptance single sampling plan with inspection errors when the fraction of defective items
is a fuzzy number. We have shown that the operating characteristics curve of this plan is like a band having high and low
bounds, its width depends on the ambiguity of proportion parameter in the lot when the samples size and acceptance numbers
are fixed. A comparison of the single sampling plans with and without inspection errors was done to study the effects upon
the characteristics. The results of this comparison show that in the sampling plan with inspection errors, there is a lower
operating characteristics band in comparison to a sampling plan without inspection errors for good processing quality. We
have also shown that the incorrect classification of a good item reduces the fuzzy probability of acceptance and incorrect
classification of a defective item results in a higher fuzzy probability of acceptance. 相似文献