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71.
Bahram Alizadeh Seyed Rasoul Seyedali Bahram Habibnia 《Petroleum Science and Technology》2013,31(23):2322-2329
AbstractIn a first attempt, Middle to Late Eocene Shahbazan Formation as a possible source rock in Dezful Embayment was geochemically investigated. Maturity indicators derived from Rock-Eval pyrolysis (Tmax and PI) and gas chromatography (CPI) show that the organic matter, which dominated by a mixed type II/III kerogen, is thermally mature and has already entered the oil window. A fair to good petroleum-generative potential is suggested by moderate to relatively high values of total organic carbon (TOC) and potential yield (S1+S2). Deposition of Shahbazan Formation under low-oxygen condition, which is represented by low pristane/phytane ratio (<1), conduced to preservation of organic matter. This is in accordance with considerable TOC contents, ranging from 1.01 to 1.72?wt%. The relation between pristane/nC17 and phytane/nC18 as well as terrigenous/aquatic ratio (~1) represent the mixed marine and terrestrially sourced organic matter. Based on the results obtained from this study, Shahbazan Formation could have been acted as a prolific oil and gas source rock. 相似文献
72.
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
73.
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
74.
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
75.
Bahram Rashidi 《International Journal of Circuit Theory and Applications》2020,48(8):1227-1243
In this paper, low-cost and two-cycle hardware structures of the PRINCE lightweight block cipher are presented. In the first structure, we proposed an area-constrained structure, and in the second structure, a high-speed implementation of the PRINCE cipher is presented. The substitution box (S-box) and the inverse of S-box (S-box−1) blocks are the most complex blocks in the PRINCE cipher. These blocks are designed by an efficient structure with low critical path delay. In the low-cost structure, the S-boxes and S-boxes−1 are shared between the round computations and the intermediate step of PRINCE cipher. Therefore, the proposed architecture is implemented based on the lowest number of computation resources. The two-cycle implementation of PRINCE cipher is designed by a processing element (PE), which is a general and reconfigurable element. This structure has a regular form with the minimum number of the control signal. Implementation results of the proposed structures in 180-nm CMOS technology and Virtex-4 and Virtex-6 FPGA families are achieved. The proposed structures, based on the results, have better critical path delay and throughput compared with other's related works. 相似文献
76.
Ana Rita Gomes Nasim Bahram Sangani Tiago G. Fernandes M. Margarida Diogo Leopold M. G. Curfs Chris P. Reutelingsperger 《International journal of molecular sciences》2020,21(24)
The central nervous system (CNS) is the most complex structure in the body, consisting of multiple cell types with distinct morphology and function. Development of the neuronal circuit and its function rely on a continuous crosstalk between neurons and non-neural cells. It has been widely accepted that extracellular vesicles (EVs), mainly exosomes, are effective entities responsible for intercellular CNS communication. They contain membrane and cytoplasmic proteins, lipids, non-coding RNAs, microRNAs and mRNAs. Their cargo modulates gene and protein expression in recipient cells. Several lines of evidence indicate that EVs play a role in modifying signal transduction with subsequent physiological changes in neurogenesis, gliogenesis, synaptogenesis and network circuit formation and activity, as well as synaptic pruning and myelination. Several studies demonstrate that neural and non-neural EVs play an important role in physiological and pathological neurodevelopment. The present review discusses the role of EVs in various neurodevelopmental disorders and the prospects of using EVs as disease biomarkers and therapeutics. 相似文献
77.
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79.
V Groh S Bahram S Bauer A Herman M Beauchamp T Spies 《Canadian Metallurgical Quarterly》1996,93(22):12445-12450
Conventional major histocompatibility complex (MHC) class I genes encode molecules that present intracellular peptide antigens to T cells. They are ubiquitously expressed and regulated by interferon gamma. Two highly divergent human MHC class I genes, MICA and MICB, are regulated by promoter heat shock elements similar to those of HSP70 genes. MICA encodes a cell surface glycoprotein, which is not associated with beta 2-microglobulin, is conformationally stable independent of conventional class I peptide ligands, and almost exclusively expressed in gastrointestinal epithelium. Thus, this MHC class I molecule may function as an indicator of cell stress and may be recognized by a subset of gut mucosal T cells in an unusual interaction. 相似文献
80.