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Seyed Mohammad Sina Mousavi Hossein Ganjidoust 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(22):3300-3307
In this study, a single-chamber microbial fuel cell (SCMFC) was used to simultaneously remove 300 mg/l phenol and generate bio-electricity. During the tests, temperature and salt content were increased from 25 to 45°C and from 0.5 to 2% (w/v), respectively. The results show that at 45°C, the removal rate increased 4 and 5%, respectively; meanwhile, power density peak increased from 34 to 43 mW/m2. Phenol removal rate increased 4% by adding 0.5% salt. The power density peak increased greatly to 45 mW/m2 after adding 1% salt to the anolyte. Initial phenol concentration was consistent for all tests and cycles for 72 h. The study demonstrates that this method can be used to remove phenol and generate bio-electricity in different conditions. 相似文献
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This study was undertaken to investigate the influence of Al–5Ti–1B and Al–5Zr master alloys on the structural characteristics and tensile properties of Al–12Zn–3 Mg–2.5Cu aluminum alloy. The optimum amount for Ti and Zr containing master alloys was selected as 1 wt.% and 6 wt.%, respectively. The results also showed that Ti containing master alloy is more effective in reducing average grain size of the alloy. T6 heat treatment was applied for all specimens before tensile testing. In heat treated condition, the average tensile strength of 505 MPa was found to be increased to 621 MPa for sample refined with 1 wt.% Al–5Ti–1B (0.05 wt.% Ti). SEM fractography of the fractured faces of several castings showed an overall macroscopically brittle appearance at low magnifications. At higher magnifications, unrefined specimens showed cracking along the grains, whereas Ti-refined specimens showed cracks in individual intermetallic compounds. 相似文献
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A novel CMOS atto-ampere current mirror (AACM) is proposed which reaches the minimum yet reported current range of 0.4 aA. Operation of this circuit is based on the source voltage modulation instead of the conventionally used gate voltage modulation which interestingly prevents usage of commonly required voltage shifting in those circuits. The proposed circuit has a simple structure prohibiting large chip area consumption which consumes extremely low power of 1.5 μW. It is thus the best choice for ultra low power low voltage (ULPLV) applications. By using a very simple frequency compensation technique, its bandwidth is widened to 15.8 kHz. Simulation results in SMIC (Semiconductor Manufacturing International Corporation) 0.18 μm CMOS technology with Hspice are presented to demonstrate the validation of the proposed current mirror. 相似文献
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Seyed Reza Falahatgar Manouchehr Salehi Mohammad Mohammadi Aghdam 《Applied Composite Materials》2010,17(5):427-440
The Dynamic Relaxation (DR) technique together with finite difference discritization is used to study the bending behavior of Mindlin composite plate including geometric nonlinearity. The overall behavior of the unidirectional composite is obtained from a three-dimensional (3D) micromechanical model, in any combination of normal and shear loading conditions, based on the assumptions of Simplified Unit Cell Method (SUCM). The composite system consists of nonlinear viscoelastic matrix reinforced by transversely isotropic elastic fibers. A recursive formulation for the hereditary integral of the Schapery viscoelastic constitutive equation in multiaxial stress state is used to model the nonlinear viscoelastic matrix material in the material level. The creep tests data is used for verification of the predicted response of the current approach. Under uniform lateral pressure, the laminated plate deformation with clamped and hinged edged constraints is predicted for various time steps. 相似文献