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131.
132.
Rahman Zahid Rehman Khaista Ali Wajid Ali Amir Burton Paul Barkat Adnan Ali Asghar Qadri S. M. Talha 《Journal of Seismology》2021,25(6):1461-1481
Journal of Seismology - The Pamir-Hindu Kush region is seismically the most dynamic and active zone that went through many devastating earthquakes. While much research is ongoing to produce seismic... 相似文献
133.
Monjezi Sara Najarchi Mohsen Mo’meni Mansour Monjezi Narges Hassuninezade Houshang 《Water Resources》2021,48(6):1013-1022
Water Resources - To water quality management of the Gotvand Reservoir, this paper attempts to determine to what extent the negative impacts of Anbar salt domes dissolution can be reduced... 相似文献
134.
Decolorization of C.I. Basic Blue 3 (BB3) by oxalate catalyzed photoelectro‐Fenton process based on carbon nanotube‐polytetrafluoroethylene (CNT‐PTFE) electrode as cathode under visible light was studied. A comparison of electro‐Fenton, photoelectro‐Fenton, and photoelectro‐Fenton/oxalate processes for decolorization of the solution containing BB3 has been performed. The results showed that color removal follows the decreasing order: photoelectro‐Fenton/oxalate > photoelectro‐Fenton > electro‐Fenton. Response surface methodology (RSM) was employed to assess individual and interactive effects of the four main independent parameters on the decolorization efficiency. A central composite design (CCD) was employed for optimization of photoelectro‐Fenton/oxalate treatment of BB3. The analysis of variance (ANOVA) showed a high coefficient of determination value (R2 = 0.958) and satisfactory prediction second‐order regression. This study clearly showed that RSM was one of the suitable methods to optimize the operating conditions. 相似文献
135.
The authors would like to thank the discusser for his considerations and comments. The discusser believes that some of the derived formulations need to be referred to his previously published works and also some related studies have not been cited. 相似文献
136.
Amir Hasanzadeh 《Astrophysics and Space Science》2012,339(2):211-221
About 70 years ago “André Danjon” a French astrophysicist showed that as elongation of the moon decreases the arc length of
crescent gets less too. By studying the recent observational data, he concluded that at 7 degree elongation, the length of
arc (cusp to cusp) will reach zero degree. Today, this value is named as Danjon limit, which points to the limit at which
the moon crescent is formed. Danjon believed that the effective factor for occurring this limit was the shadows of moon’s
mountains. Later researchers have obtained different values for this limit. In this research based on the new data, the decreasing
dependence of length of arc versus elongation was obtained. The results show that the Danjon limit is about 5 degrees. The
effective factors to form the Danjon limit are then given and discussed. By considering the effects of astronomical seeing
and shadows of lunar features, the values of the arc length were calculated and compared with the observational data curve.
The results of this study show good agreement with the observational data. The present research shows that the above-mentioned
effects can reduce the length of arc. The effect of libration and roughness of the lunar terrain of the moon in forming the
moon crescent were also considered, and the possibility of observing thinner crescents by photometric model and breaking the
Danjon limit were given. 相似文献
137.
138.
Effect of Temporal Changes in Air Injection Rate on Air Sparging Performance Groundwater Remediation 下载免费PDF全文
Air sparging (AS) is a commonly applied method for treating groundwater contaminated with volatile organic compounds (VOCs). When using a constant injection of air (continuous mode), a decline in remediation efficiency is often observed, resulting from insufficient mixing of contaminants at the pore scale. It is well known that turning the injection on and off (pulsed mode) may lead to a better remediation performance. In this article, we investigate groundwater mixing and contaminant removal efficiency in different injection modes (i.e., continuous and pulsed), and compare them to those achieved in a third mode, which we denote as “rate changing.” In this mode, injection is always on, and its rate is varying with time by abrupt changes. For the purpose of this investigation, we conducted two separate sets of experiments in a laboratory tank. In the first set of experiments, we used dye plume tracing to characterize the mixing induced by AS. In the second set of experiments, we contaminated the tank with a VOC and compared the remediation efficiency between the different injection modes. As expected, we observed that time‐variable injection modes led to enhanced mixing and contaminant removal. The decrease in contaminant concentrations during the experiment was found to be double for the “rate changing” and “pulsed” modes compared to the continuous mode, with a slightly preferable performance for the “rate changing” mode. These results highlight the critical role that mixing plays in AS, and support the need for further investigation of the proposed “rate changing” injection mode. 相似文献
139.
Stability of the time‐domain analysis method including a frequency‐dependent soil–foundation system 下载免费PDF全文
A number of methods have been proposed that utilize the time‐domain transformations of frequency‐dependent dynamic impedance functions to perform a time‐history analysis. Though these methods have been available in literature for a number of years, the methods exhibit stability issues depending on how the model parameters are calibrated. In this study, a novel method is proposed with which the stability of a numerical integration scheme combined with time‐domain representation of a frequency‐dependent dynamic impedance function can be evaluated. The method is verified with three independent recursive parameter models. The proposed method is expected to be a useful tool in evaluating the potential stability issue of a time‐domain analysis before running a full‐fledged nonlinear time‐domain analysis of a soil–structure system in which the dynamic impedance of a soil–foundation system is represented with a recursive parameter model. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
140.
Vertical earthquake response of megawatt‐sized wind turbine with soil‐structure interaction effects 下载免费PDF全文
The dynamic response of a wind turbine on monopile is studied under horizontal and vertical earthquake excitations. The analyses are carried out using the finite element program SAP2000. The finite element model of the structure is verified against the results of shake table tests, and the earthquake response of the soil model is verified against analytical solutions of the steady‐state response of homogeneous strata. The focus of the analyses in this paper is the vertical earthquake response of wind turbines including the soil‐structure interaction effects. The analyses are carried out for both a non‐homogeneous stratum and a deep soil using the three‐step method. In addition, a procedure is implemented which allows one to perform coupled soil‐structure interaction analyses by properly tuning the damping in the tower structure. The analyses show amplification of the ground surface acceleration to the top of the tower by a factor of two. These accelerations are capable of causing damage in the turbine and the tower structure, or malfunctioning of the turbine after the earthquake; therefore, vertical earthquake excitation is considered a potential critical loading in design of wind turbines even in low‐to‐moderate seismic areas. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献