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Chinese Journal of Polymer Science 2013年第12期31卷 1660-1669页

作者： Mohammad ali Karimi Zarchi ali Tarabsaz Department of Chemistry College of ScienceYazd University

A new polymeric reagent, cross-linked poly（4-vinylpyridine） supported azide ion, [P4-VP]N3, was introduced as polymeric reagents for efficient and regioselective conversion of epoxides to azidohydrins in the presence of cross-linked poly（4-vinylpyridine） supported sulfuric acid, [P4-VP]H2SO4, as a solid proton source and as catalyst under solvent-free conditions. The advantages of this polymeric reagent over some of those reported in the literature are easy work-up procedure and regeneration of the reagent.

关键词： Ring opening of epoxide fl-Azidoalcohols Poly(4-vinytpyridine) Solvent-free conditions Regioselectivity.

Design and Optimization of 3D Radial Slot Grain Configuration

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Chinese Journal of Aeronautics 2010年第4期23卷 409-414页

作者： ali Kamran School of Astronautics Beijing University of Aeronautics and Astronautics

Upper stage solid rocket motors （SRMS） for launch vehicles require a highly efficient propulsion system. Grain design proves to be vital in terms of minimizing inert mass by adopting a high volumetric efficiency with minimum possible sliver. In this arti- cle, a methodology has been presented for designing three-dimensional （3D） grain configuration of radial slot for upper stage solid rocket motors. The design process involves parametric modeling of the geometry in computer aided design （CAD） software through dynamic variables that define the complex configuration. Grain bum back is achieved by making new surfaces at each web increment and calculating geometrical properties at each step. Geometrical calculations are based on volume and change-in-volume calculations. Equilibrium pressure method is used to calculate the internal ballistics. Genetic algorithm （GA） has been used as the optimizer because of its robustness and efficient capacity to explore the design space for global optimum solution and eliminate the requirement of an initial guess. Average thrust maximization under design constraints is the objective function.

关键词： solid rocket motors 3D grains radial slot configuration internal ballistics computer aided design heuristic optimization genetic algorithm

Decrease of back recombination rate in CdS quantum dots sensitized solar cells using reduced graphene oxide

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Chinese Physics B 2015年第4期24卷 372-377页

作者： ali Badawi Department of Physics Faculty of Science Taif University

The photovoltaic performance of CdS quantum dots sensitized solar cells （QDSSCs） using the 0.2 wt% of reduced graphene oxide and TiO2 nanoparticles （RGO＋TiO2 nanocomposite） photoanode is investigated. CdS QDs are adsorbed onto RGO＋TiO2 nanocomposite films by the successive ionic layer adsorption and reaction （SILAR） technique for several cycles. The current density-voltage （J-V） characteristic curves of the assembled QDSSCs are measured at AM1.5 simulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO＋TiO2 nanocomposite photoanode achieve a 33% increase in conversion efficiency （η） compared with those based on plain TiO2 nanoparticle （NP） photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO＋TiO2 nanocomposite photoanodes. The lifetime constant （τ） for CdS QDSSC based on the RGO＋TiO2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO2NPs photoanode.

关键词： reduced graphene oxide nanocomposite photoanode back recombination rate quantum dots sensitized solar cell

Effect of mineral additives and permeability reducing admixtures having different action mechanisms on mechanical and durability performance of cementitious systems

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Frontiers of Structural and Civil Engineering 2021年第5期15卷 1277-1291页

作者： ali NEMATZADEH Burcu AYTEKIN ali MARDANL-AGHABAGLOU Department of Civil Engineering Bursa Uludag UniversityNilufer-Bursa 16059Turkey

In this paper,the effect of usage of the permeability reducing admixture(PRA)having different action mechanisms on hardened state properties of cementitious systems containing mineral additives is *** this aim,three commercial PRAs were used during *** effective parameters in the first and third PRAs were air-entraining and high-rate air-entraining,*** second one contained the insoluble calcium carbonate residue and had a small amount of the air-entraining *** mixes with binary and ternary cementitious systems were prepared by partially replacing cement with fly ash and *** hardened state properties of mortar mixtures such as compressive strength,ultrasonic pulse velocity,water absorption,drying shrinkage and freeze-thaw resistance were *** ternary cement-based mixture having both fly ash and metakaolin was selected as the most successful mineral-additive bearing mix in regard to hardened state *** this sense,PRA-B,with both insoluble residues and a small amount of air-entraining properties,showed the best performance among the mixtures containing *** combined use of mineral additive and PRA had a more positive effect on the properties of the mixes.

关键词： cementitious system mineral additive permeability reducing admixture mechanical properties durability performance

A Review on Plug-in Electric Vehicles:Introduction, Current Status, and Load Modeling Techniques

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 412-425页

作者： ali Ahmadian Behnam Mohammadi-Ivatloo ali Elkamel Department of Electrical Engineering University of BonabBonabIran Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam College of Engineering Khalifa University of Science and Technologythe Petroleum InstituteAbu DhabiUnited Arab Emirates

Plug-in electric vehicle(PEV) load modeling is very important in the operation and planning studies of modern power system nowadays. Several parameters and considerations should be taken into account in PEV load modeling, making it a complex problem that should be solved using appropriate techniques. Different techniques have been introduced for PEV load modeling and each of them has individual specifications and features. In this paper, the most popular techniques for PEV load modeling are reviewed and their capabilities are evaluated. Both deterministic and probabilistic methods are investigated and some practical and theoretical hints are presented. Moreover, the characteristics of all techniques are compared with each other and suitable methods for unique applications are proposed. Finally, some potential research areas are presented for future works.

关键词： Plug-in electric vehicles load modeling deterministic and probabilistic techniques distribution networks

Estimation of crowd density from UAVs images based on corner detection procedures and clustering analysis

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Geo-Spatial Information Science 2019年第1期22卷 23-34页

作者： ali Almagbile Department of Geography Yarmouk UniversityIrbidJordan

With rapid developments in platforms and sensors technology in terms of digital cameras and video recordings,crowd monitoring has taken a considerable attentions in many disciplines such as psychology,sociology,engineering,and computer *** is due to the fact that,monitoring of the crowd is necessary to enhance safety and controllable movements to minimize the risk particularly in highly crowded incidents(***).One of the platforms that have been extensively employed in crowd monitoring is unmanned aerial vehicles(UAVs),because UAVs have the capability to acquiring fast,low costs,high-resolution and real-time images over crowd *** addition,geo-referenced images can also be provided through integration of on-board positioning sensors(***/IMU)with vision sensors(digital cameras and laser scanner).In this paper,a new testing procedure based on feature from accelerated segment test(FAST)algorithms is introduced to detect the crowd features from UAV images taken from different camera orientations and *** proposed test started with converting a circle of 16 pixels surrounding the center pixel into a vector and sorting it in ascending/descending order.A single pixel which takes the ranking number 9(for FAST-9)or 12(for FAST-12)was then compared with the center *** assessment in terms of completeness and correctness was used to assess the performance of the new testing procedure before and after filtering the crowd *** results show that the proposed algorithms are able to extract crowd features from different UAV ***,the values of Completeness range from 55 to 70%whereas the range of correctness values was 91 to 94%.

关键词： Unmanned Aerial Vehicle(UAV) crowd density corner detection Feature from Accelerated Segment Test(FAST)algorithm clustering analysis

Generating genuine multipartite entanglement via XY-interaction and via projective measurements

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Chinese Physics B 2014年第12期23卷 59-65页

作者： Mazhar ali Department of Electrical Engineering COMSATS Institute of Information Technology22060 Abbottabad Pakistan Naturwissenschaftlich-Technische Fakultt Universitt SiegenWalter-Flex-Straβe 357068 Siegen Germany

We have studied the generation of multipartite entangled states for the superconducting phase qubits. The experiments performed in this direction have the capacity to generate several specific multipartite entangled states for three and four qubits. Our studies are also important as we have used a computable measure of genuine multipartite entanglement whereas all previous studies analyzed certain probability amplitudes. As a comparison, we have reviewed the generation of multipartite entangled states via von Neumann projective measurements.

关键词： genuine multipartite entanglement superconducting qubits von Neumann measurements

Computational methods for fracture in rock:a review and recent advances

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 273-287页

作者： ali JENABIDEHKORDI Institute of Structural Mechanics Bauhaus Universitat-WeimarD-99423 WeimarGermany

We present an overview of the most popular state-of-the-art computational methods available for modelling fracture in rock. The summarized numerical methods can be classified into three categories: Continuum Based Methods, Discrete Crack Approaches, and Block-Based Methods. We will not only provide an extensive review of those methods which can be found elsewhere but particularly address their potential in modelling fracture in rock mechanics and geotechnical engineering. In this context, we will discuss their key applications, assumptions, and limitations. Furthermore, we also address 'general' difficulties that may arise for simulating fracture in rock and fractured rock. This review will conclude with some final remarks and fiiture challenges.

关键词： numerical modelling method development rock mechanics fractured rock rock fracturing

Decoherence of genuine multipartite entanglement for local non-Markovian–Lorentzian reservoirs

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Chinese Physics B 2015年第12期24卷 215-221页

作者： Mazhar ali Department of Electrical Engineering Faculty of Engineering Islamic University in Madinah

We study decoherence effects on genuine multipartite entanglement for three and four qubits, spatially separated and subjected to local Lorentzian reservoirs. Employing recent techniques to compute genuine negativity for multipartite systems and an exact solvable model, we analyze the dynamics of genuine entanglement for different coupling bandwidths and detunings. We find that collapses and revivals can occur by varying these parameters for various multipartite quantum states.

关键词： genuine negativity decoherence random states

Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 1016-1024页

作者： ali AREFNIA ali DEHGHANBANADAKI Khairul Anuar KASSIM Department of Geotechnics&Transportation School of Civil EngineeringFaculty of EngineeringUniversiti Teknologi MalaysiaSkudai81310Malaysia Department of Civil Engineering Roudehen BranchIslamic Azad UniversityTehranIran Department of Civil Engineering Damavand BranchIslamic Azad UniversityDamavandTehranIran

This study investigated the use of recycled tire-derived aggregate(TDA)mixed with kaolin as a method of increasing the ultimate bearing capacity(UBC)of a strip *** 1g physical modeling tests were prepared in a rigid box of 0.6 m×0.9 m in plan and 0.6 m in *** sample preparation,0%,20%,40%,or 60%(by weight)of powdery,shredded,small-sized granular(G 1–4 mm)or large-sized granular(G 5–8 mm)TDA was mixed with the kaolin.A strip footing was then placed on the stabilized kaolin and was caused to fail under stress-controlled conditions to determine the UBC.A rigorous 3D finite element analysis was developed in Optum G-3 to determine the UBC values based on the experimental test *** experimental results showed that,except for the 20%powdery TDA,the TDA showed an increase in the UBC of the strip *** kaolin mixed with 20%G(5–8 mm),the UBC showed a threefold increase over that for the unreinforced *** test with 20%G(1–4 mm)recorded the highest subgrade *** was observed that the UBC calculated using finite element modeling overestimated the experimental UBC by an average of 9%.

关键词： kaolin physical modeling tests stabilization numerical modeling