检索结果-南通市图书馆

Assessment of renewable energy:Status,challenges,COVID-19 impacts,opportunities,and sustainable energy solutions in Africa

在线全文

学校读者我要写书评

暂无评论

Energy and Built Environment 2022年第3期3卷 348-362页

作者： Mohammad amir Sana Zubair Khan Department of Electrical Engineering Faculty of Engineering and TechnologyJamia Millia Islamia(Central University)New Delhi 110025India Amity Institute of Environmental Science(AIES) Amity UniversityNoidaUttar Pradesh 201313India

Today’s more focus and efforts are being put by all the energy leaders towards power generation using renewable energy ***,these resources are becoming affordable to facilitate a swift shift towards green and clean *** strategic assets are an add-on for all the developing nations in terms of *** technological advancement and power market revolution resulting in an adequate reduction of renewable energy cost and *** paper mainly focusing on Covid-19 impacts in the African energy ***,analyzing recent developments in African renewable energy generation that holds the immense capacity for *** paper highlighting the recommendations in response to the COVID-19 pandemic for the African renewable energy *** paper is a result of rigorous analysis based on major issues governing sustainable solutions for *** review paper comes up with effective conclusions to address the challenges in the cur-rent pandemic *** Africa abundance of resources is found with huge potential for the generation of *** still,Africa undergoing a phase of serious crises because they are not able to tap its huge capital of renewable *** is a subsequent need for power grid restructuring,energy storage technologies,and parallel mitigation of environmental factors with seasonal *** review analysis bringing a better opportunity for all issues towards sustainable solutions,that will ease the renewable energy status in *** is observed that there is an inevitable need to focus on having strong government policy frameworks and proper *** various recommendations are required to swing towards renewable energy ***-bined efforts are required in luring foreign investments and to address feasible issues like setting-up *** paper demonstrated a smart energy system using a proposed machine learning-based framework for enhancing the PV forecasting an

关键词： Artificial intelligence COVID-19 CO_(2)emission International Solar Alliance(ISA) Renewable Energy Resources(RER) Western Africa Power Pool

Analysis of the hot deformation of ZK60 magnesium alloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2017年第4期5卷 369-387页

作者： amir Hadadzadeh Mary A.Wells Mechanical and Mechatronics Engineering Department University of WaterlooWaterlooON N2L 3G1Canada

Hot deformation of cast-homogenized and extruded(in both the extrusion and transverse directions)ZK60 magnesium alloy was conducted using the Gleeble®3500 thermal-mechanical simulation testing system.A new approach to model the high temperature constitutive behavior of the alloy was done using two well-known equations(*** sine and Ludwig equations).For this approach,the deformation conditions were divided into regimes of low and high temperature and strain rate(four regimes).Constitutive model development was conducted in each regime and the material parameters(P)were evaluated as strain,strain rate and temperature-dependent variables;P(ε,ε,T).Using this approach,the flow curves were predicted with high accuracy relative to the experimental ***,detailed information on the evolution of hot deformation activation energy was obtained using the modified hyperbolic sine *** the modified Ludwig equation,details of strain hardening and strain rate sensitivity of the ZK60 material during hot deformation were obtained.

关键词： ZK60 magnesium alloy Hot deformation Constitutive modeling Zener-Hollomon Hyperbolic sine Ludwig equation

Feasibility of Solar Tracking System for PV Panel in Sunbelt Region

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 395-403页

作者： Soulayman Soulayman Mohamad Hamoud Mohamad-amir Hababa Wassim Sabbagh the Department of Applied Physics Higher Institute for Applied Sciences and TechnologyDamascusP O Box 31983Syria

In the study of the feasibility of solar tracking systems for crystalline silicon photovoltaic(PV)panels in hot and cold regions,it is argued recently that a tracking system is not necessary for sunbelt countries owing to the overheating that results from excessive exposure to solar *** conclusion has been formulated based on a mathematical model,which in turn is based on the assumption that the PV module temperature can be calculated using an empirical relation of this temperature to ambient temperature,available solar irradiance,and nominal operation cell temperature(NOCT).To support this conclusion,it is claimed that the mathematical model is validated ***,this assumption is vague and widely used in the *** objective of the present work is to reevaluate the above-mentioned assumption and to discuss the results deriving from *** is shown experimentally in the present work that the above-mentioned assumption overestimates the PV module *** a solar irradiance of 900 W/m2,ambient temperature of 25℃,and wind speed of 5 m/s,the measured PV module temperature is lower than the value calculated based on the mentioned assumption by 29.26%.

关键词： Photovoltaic(PV)module temperature wind speed influence PV module efficiency experimental verification Damascus clear-sky conditions

PPA-SiO_2 catalyzed efficient synthesis of polyhydroquinoline derivatives through Hantzsch multicomponent condensation under solvent-free conditions

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第7期22卷 807-810页

作者： amir Khojastehnezhad Farid Moeinpour Abolghasem Davoodnia Department of Chemistry Faculty of SciencesIslamic Azad UniversityMashhad BranchMashhad 91735-413Iran Department of Chemistry Faculty of SciencesIslamic Azad UniversityBandar Abbas BranchIran

Silica gel-supported polyphosphoric acid （PPA-SiO2） was found to be an efficient catalyst for the one-pot four-component Hantzsch condensation reaction of aryl aldehydes, dimedone, ethyl acetoacetate and ammonium acetate to afford the corresponding polyhydroquinoline derivatives in high yields. The main advantages of the present approach are short reaction times, clean reaction profiles, simple experimental and workup procedures.

关键词： Multicomponent reaction One-pot synthesis Solvent-free Polyhydroquinoline derivatives Silica-supported polyphosphoric acid (PPA-SiO2)

Machine learning in geosciences and remote sensing

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2016年第1期7卷 3-10页

作者： David J.Lary amir H.Alavi amir H.Gandomi Annette L.Walker Hanson Center for Space Science University of Texas at Dallas Department of Civil and Environmental Engineering Michigan State University BEACON Center for the Study of Evolution in Action Michigan State University Aerosol and Radiation Section Naval Research Laboratory

Learning incorporates a broad range of complex procedures. Machine learning（ML） is a subdivision of artificial intelligence based on the biological learning process. The ML approach deals with the design of algorithms to learn from machine readable data. ML covers main domains such as data mining, difficultto-program applications, and software applications. It is a collection of a variety of algorithms（e.g. neural networks, support vector machines, self-organizing map, decision trees, random forests, case-based reasoning, genetic programming, etc.） that can provide multivariate, nonlinear, nonparametric regression or classification. The modeling capabilities of the ML-based methods have resulted in their extensive applications in science and engineering. Herein, the role of ML as an effective approach for solving problems in geosciences and remote sensing will be highlighted. The unique features of some of the ML techniques will be outlined with a specific attention to genetic programming paradigm. Furthermore,nonparametric regression and classification illustrative examples are presented to demonstrate the efficiency of ML for tackling the geosciences and remote sensing problems.

关键词： Machine learning Geosciences Remote sensing Regression Classification

Synthesis of new 4,6-diaryl-2-(arylthio)nicotinonitriles in Triton X-100 aqueous micellar media

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2015年第2期26卷 263-266页

作者： Mohammad Reza Poor Heravi amir Soufi Department of Chemistry Payame Noor University

In this communication,we report four component condensations of acetophenone,arylaldehydes,arylthiol,and malononitrile in the presence of Triton X-100（5 mol%） aqueous *** reaction led to the formation of 4,6-diaryl-2-（arylthio）nicotinonitrile new derivatives in good *** FT-IR,^19F NMR,^1H NMR,^13C NMR spectra and elemental analysis confirm the structure of compounds.

关键词： Nicotinonitriles Triton X-100 Aqueous micellar media Non-ionic surfactant

An equivalent linearization method for nonlinear Van der Pol oscillator subjected to random vibration using orthogonal functions

在线全文

学校读者我要写书评

暂无评论

Control Theory and Technology 2018年第1期16卷 49-57页

作者： amir YOUNESPOUR Hosein GHAFFARZADEH Bahman Farahmand AZAR Faculty of Civil Engineering University of Tabriz Tabriz 51666 Iran

This paper deals with the idea of the orthogonal functions in the equivalent linearization of the nonlinear systems. Block Pulse （BP） function gives effective tools to approximate complex problems. The aim of this work is on using properties of the BP function as an orthogonal function in process of linearization. The BP functions have been used to propose an equivalent linearization method in the time domain to determine the unknown linearization coefficients. The accuracy of the proposed method compared with the other equivalent linearization approaches, including the regulation linearization and the dual criterion linearization methods. This study exploited the nonlinear Van der Pol oscillator system under stationary random excitation to demonstrate the feasibility of the proposed method. The validity of the analytical method is verified by applying different values of nonlinearity and intensity of excitation. Besides, by comparing the mean-square responses and frequency response functions of the linearized systems for a wide range of nonlinearity depicted the present method is in agreement with other methods.

关键词： Nonlinear system equivalent linearization orthogonal functions Van der Pol oscillator random vibration

Analytical approach for predicting local scour downstream of submerged sluice gate with an apron

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2022年第4期37卷 522-537页

作者： Arsalan Mostaani amir H.Azimi Department of Civil Engineering Lakehead University

A new analytical method was evaluated for predicting scour profile downstream of a submerged sluice gate with an apron. The differential equations between bed Shear stress and Scour profile Curvature(SSC model) were utilized to predict the scour profile in both temporal and equilibrium stages. A jet momentum flux was considered as an external source of erosion on a hypothetical particle ring as the boundary between the flow and sediment bed. The scour length and sediment resistance factor were the two unknowns in the governing differential equations. Two solution strategies were introduced to provide a closed-form solution by using the prediction equations of maximum scour depth from the literature and by employing the von K arm an momentum integral equation. The first strategy was used to investigate the effect of jet angle of attack and the angle of the maximum scour slope on the prediction of scour profile. A sensitivity analysis was performed to determine an acceptable range for the maximum scour slope. The shear stress at the location of maximum scour was also estimated using the von K arm an momentum integral equation and the model was modified for erodible curved beds. The modified von K arm an equation was linked with SSC equations to predict the characteristic lengths of scour in temporal and equilibrium stages. Variations in bed shear stress at the location of maximum scour depth decreased non-linearly with time and reached the sediment critical shear stress at equilibrium. Four hydrodynamic regimes were classified to define the temporal variations of bed shear stress. The maximum error for prediction of scour profile with time occurred at the beginning of scour and the proposed model overestimated the maximum scour depth by 34.8% and underestimated the scour length by 7.6%.

关键词： Erosion Scour Turbulent wall jet Sediment transport Bed shear stress von Kármán momentum integral equation

Comparative and Competitive Adsorption of Cu（II） and Cd（II） Using Scoria： Equilibrium, Kinetic and Thermodynamic Studies

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2017年第3期33卷 471-478页

作者： SEYFI Sara AZADMEHR amir Reza MAGHSOUDI Abbas Department of Mining & Metallurgical Engineering Amirkabir University of Technology Tehran *** Iran

Heavy metals, such as Cu（Ⅱ） and Cd（Ⅱ） are among the hazardous pollutants that lead to severe ecological problems and have a toxic effect on living organisms. This study was carried out on adsorption of Cu（Ⅱ） and Cd（Ⅱ） from single-and multi-component aqueous solutions with Iranian scoria. Two- and three-parameter isotherm models, such as Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Khan and Toth have been studied for single and bi- nary adsorption of Cu（Ⅱ） and Cd（Ⅱ） onto scoria. The best result was attained from Langmuir model for Cu（Ⅱ） and Cd（Ⅱ） ions in single and binary solution. Therefore, homogenous adsorption is dominated, which was emphasized by three-parameter isotherm models. Based on the value of the free energy of adsorption for Cu（Ⅱ） and Cd（Ⅱ）, the inte-raction between these ions and scoria is a physical adsorption. In order to investigate competitive adsorption behavior, modified and extended Langmuir and Freundlich models have been studied, which indicated that adsorption of Cu（Ⅱ） and Cd（Ⅱ） on scoria has synergistic behavior. Extended Freundlich model and modified Langmuir model described Cu（Ⅱ） and Cd（Ⅱ） adsorption onto scoria, respectively.

关键词： Adsorption Individual isotherm Multi-component isotherm Kinetics Thermodynamic