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Fabrication of a Highly Sensitive Hydrazine Electrochemical Sensor Based on Bimetallic Au-Pt Hybrid Nanocomposite onto modified Electrode

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Nano-micro Letters 2010年第4期2卷 296-305页

作者： Azadeh Azadbakht Amir reza Abbasi Department of Chemistry Faculty of Basic ScienceIslamic Azad UniversityKhorramabad Branch Faculty of Science and Engineering Islamic Azad UniversityDoroud Branch

In this research a novel nickel complex was used as electrocatalyst for electrooxidation of hydrazine.A nano-structured nickel-complex was electrodeposited on a bimetallic Au-Pt inorganic-organic hybrid nanocomposite modified *** electrode possesses a three-dimensional(3D) porous network nanoarchitecture,in which the bimetallic Au-Pt NPs serving as metal nanoparticle based microelectrode ensembles are distributed in the matrix of interlaced 3,3′,5,5′-Tetramethylbenzidine(TmB) organic nanofibers(NFs).Surface structure and composition of the sensor was characterized by scanning electron *** oxidation of hydrazine on the surface of modified electrode was investigated with cyclic voltammetry *** results showed that the nickelcomplex films displayed excellent electrochemical catalytic activities towards hydrazine *** hydrodynamic amperometry at rotating modified electrode at constant potential versus reference electrode was used for detection of *** optimized conditions the calibration plots were linear in the concentration range of 0.2-85 μm and detection limit was found to be 0.1 μ*** modified electrode exhibited reproducible behavior and a high level stability during the electrochemical experiments,making it particularly suitable for the analytical purposes.

关键词： 3,3′,5,5′-Tetramethylbenzidine Hydrazine Nanocomposite electrodes Nanofiber

Strongly Clean matrix Rings over a Skew monoid Ring

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代数集刊:英文版 2023年第3期30卷 361-370页

作者： Arezou Karimimansoub mohammad-reza(Rafsanjani)Sadeghi Department of mathematics and Computer Science Amirkabir University of TechnologyTehranP.O.Box ***Iran

Let R be a ring with an endomorphismσ,F∪{0}the free monoid generated by U={u1,…,ut}with 0 added,and m a factor of F obtained by setting certain monomials in F to 0 such that m^(n)=0 for some *** we can form the non-semiprime skew monoid ring R[m;σ].A local ring R is called bleached if for any j∈J(R)and any u∈U(R),the abelian group endomorphisms l_(u)−r_(j) and l_(j)−r_(u) of R are *** R[m;σ],we provide various classes of both bleached and non-bleached local *** of the main problems concerning strongly clean rings is to characterize the rings R for which the matrix ring m_(n)(R)is strongly *** investigate the strong cleanness of the full matrix rings over the skew monoid ring R[m;σ].

关键词： skew monoid rings strongly clean rings matrix rings

Landslide susceptibility mapping using machine learning algorithms and comparison of their performance at Abha Basin,Asir Region,Saudi Arabia

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Geoscience Frontiers 2021年第2期12卷 639-655页

作者： Ahmed mohamed Youssef Hamid reza Pourghasemi Geology Department Faculty of ScienceSohag UniversityEgypt Geological Hazards Department Applied Geology SectorSaudi Geological SurveyP.O.Box 54141Jeddah21514Saudi Arabia Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran

The current study aimed at evaluating the capabilities of seven advanced machine learning techniques(mLTs),including,Support Vector machine(SVm),Random Forest(RF),multivariate Adaptive Regression Spline(mARS),Artificial Neural Network(ANN),Quadratic discriminant Analysis(QDA),Linear discriminant Analysis(LDA),and Naive Bayes(NB),for landslide susceptibility modeling and comparison of their *** machine learning algorithms with spatial data types for landslide susceptibility mapping is a vitally important *** study was carried out using GIS and R open source software at Abha Basin,Asir Region,Saudi ***,a total of 243 landslide locations were identified at Abha Basin to prepare the landslide inventory map using different data *** the landslide areas were randomly separated into two groups with a ratio of 70%for training and 30%for validating *** landslide-variables were generated for landslide susceptibility modeling,which include altitude,lithology,distance to faults,normalized difference vegetation index(NDVI),landuse/landcover(LULC),distance to roads,slope angle,distance to streams,profile curvature,plan curvature,slope length(LS),and *** area under curve(AUC-ROC)approach has been applied to evaluate,validate,and compare the mLTs *** results indicated that AUC values for seven mLTs range from 89.0%for QDA to 95.1%for *** findings showed that the RF(AUC=95.1%)and LDA(AUC=941.7%)have produced the best performances in comparison to other *** outcome of this study and the landslide susceptibility maps would be useful for environmental protection.

关键词： Landslide susceptibility machine learning algorithms Variables importance Saudi Arabia

Trends in feed evaluation for poultry with emphasis on in vitro techniques

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Animal Nutrition 2021年第2期7卷 268-281页

作者： Faegheh Zaefarian Aaron J.Cowieson Katrine Pontoppidan m.reza Abdollahi Velmurugu Ravindran monogastric Research Centre School of Agriculture and EnvironmentMassey UniversityPalmerston North 4442New Zealand DSm Nutritional Products Wurmisweg 576KaiseraugstSwitzerland Novozymes A/S DK-2800 KgsLyngbyDenmark

Accurate knowledge of the actual nutritional value of individual feed ingredients and complete diets is critical for efficient and sustainable animal *** this reason,feed evaluation has always been in the forefront of nutritional *** evaluation for poultry involves several approaches that include chemical analysis,table values,prediction equations,near-infrared reflectance spectroscopy,in vivo data and in vitro digestion *** these,the use of animals(in vivo)is the most valuable to gain information on nutrient utilization and is more predictive of bird ***,in vivo methods are expensive,laborious and *** is therefore important to establish in vitro methods that are reliable,rapid and practical to assess the nutritional quality of feed ingredients or complete *** of the technique is crucial,as poor prediction will have a negative impact on bird performance and,increase feed cost and environmental *** this review,the relevance and importance of feed evaluation in poultry nutrition will be highlighted and the various approaches to evaluate the feed value of feed ingredients or complete diets will be *** in and practical limitations encountered in feed evaluation science,with emphasis on in vitro digestion techniques,will be discussed.

关键词： Poultry Feed evaluation In vivo assay In vitro techniques Protein Energy

Experimental and numerical investigation of design optimization of a partial admitted supersonic turbine

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Propulsion and Power Research 2013年第1期2卷 70-83页

作者： reza Aghaei tog Abolghasem m.Tousin Amirkabir University of Technology TehranPO.BOX 15875-4413Iran

To obtain a high specific work output,the large pressure ratios across the turbine are *** can be achieved using a supersonic *** the fluid mass flow is low,the impulse kind of one or two stages supersonic turbine is *** prevent losses due to low blade aspect ratio and issues related to manufacturing and industrial problems,the turbine is used in partial admission *** show that the turbine efficiency is highly dependent on the amount of partial admission *** turbine efficiency in full admission is high,but the use of partial admission lowers the additional ***,there will be a degree of partial admission in which the turbine will have the highest *** aim of this work is to achieve the optimum partial admission for a special impulse turbine as a case ***,in the beginning,an appropriate model of losses is ***,using a nonlinear design optimization code,the partial admission of an impulse supersonic turbine is *** code is written using a genetic ***,using three-dimensional numerical analysis,the optimal model will be *** the optimization problem,the turbine efficiency is the objective *** amount of design parameters and constraints used in this process are ten and eight,*** the optimization process,prototypes of designed and modified turbines are made and *** results were compared and *** results showed that the turbine efficiency is improved between 2.5%and 3%depending on various operation conditions.

关键词： Partial admission Non-linear optimization Genetic algorithm Three-dimensional(3D)numerical analysis Impulse turbine

Performance of passive and reactive profiled median barriers in traffic noise reduction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 78-86页

作者： mohammad reza mONAZZAm Samaneh momen Bellah FARD Occupational Hygiene Department School of Public HealthTehran University of Medical Sciences Department of Environmental Science Graduate School of the Environment and EnergyScience and Research BranchIslamic Azad University

median noise barriers, like parallel noise barriers, can be employed to reduce the impact of traffic on roadside communities via the direct propagation path. The performance of different shapes of median barriers was compared using reactive and passive surfaces and a 2D boundary element method (BEm). In the case of reactive surfaces, quadratic residue diffusers (QRDs) and primitive root diffusers (PRDs) were used on the top and stem surfaces of median barriers. To introduce passive barriers, two different absorbent materials including fibrous material and a grass surface with flow resistivity of 20 000 and 2500 kg/(s·m2), respectively, were similarly applied. The effect of thin absorptive barriers was similar at lower frequencies and better at mid and high frequencies to that of their equivalent rigid barriers. more improvement was achieved by covering the top surface of thick barriers with grass rather than with fibrous material. The performance of QRD and PRD barriers where the diffuser was located on the top surface was more frequency dependent than that of barriers coated with fibrous material. A comparison of the average A-weighted insertion loss in the thick barriers showed that the greatest improvement (2.59 dB (A)) was achieved using a barrier of 30-cm thickness covered with grass.

关键词： Absorption Quadratic residue diffuser (QRD) Primitive root diffuser (PRD) Noise barrier

Sol-gel derived nanocrystalline and mesoporous barium strontium titanate prepared at room temperature

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Particuology 2011年第3期9卷 235-242页

作者： mohammad reza mohammadi Derek J.Fray Department of materials Science & Engineering Sharif University of Technology Department of materials Science & metallurgy University of Cambridge

Perovskite-type barium strontium titanate （BST） thin films and powders with nanocrystalline and mesoporous structure were prepared by a straightforward particulate sol-gel route at room temperature. The prepared sol had a narrow particle size distribution of about 20 nm. X-ray diffraction （XRD） revealed that phase composition and preferable orientation growth of BST depended upon the annealing temperature. Transmission electron microscope （TEm） images showed that the crystallite size of the powders decreased with increasing annealing temperature from 8 nm at 25 ℃ down to 5 nm at 800 ℃. Field emission scanning electron microscope （FE-SEm） analysis and atomic force microscope （AFm） images revealed that BST thin films had mesoporous and nanocrystafiine structure with average grain size of 3Onm at 600 ℃. Based on Brunauer-Emmett-Teller （BET） analysis, the synthesized BST showed mesoporous structure containing nnres with needle, and nlate shanes and BET surface area in the range of 49-32 m^2/g at 500-800℃

关键词： Barium strontium titanate Room temperature Sol-gel chemistry Nanostructure

Effect of particle size on high-pressure methane adsorption of coal

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Petroleum Research 2016年第1期1卷 53-58页

作者： Jie Zou reza rezaee Department of Petroleum Engineering Curtin UniversityWestern AustraliaAustralia

Adsorbed gas cannot be neglected in the evaluation of coalbed methane and shale gas since a significant proportion of gas is stored in the form of adsorbed *** methane of coal and shale has been widely studied by high-pressure methane adsorption *** sample treatment of the experiment,the sample is crushed and sieved to a particular particle size ***,how particle size influence high-pressure methane adsorption is still *** this study,low-pressure nitrogen(N_(2))and high-pressure methane adsorption have been measured on coal samples with different particle *** to N2 sorption analysis,pore volume and surface area increase with particle size *** size distribution of small pores(m)changes among varying particle *** volume proportion of small pores(m)increases and pore volume proportion of big pores(>10nm)decreases with decreasing particle *** particle size by crushing sample introduces new connectivity for closed pores to the particle *** responses of isotherms of high-pressure methane adsorption are different with different particle *** adsorption at initial pressure(145psi)increases with decreasing particle *** increase rate at high pressure(435-870psi)decreases with particle size *** can be explained that fine sample has more pore volume and higher pore volume proportion of small pores(m).Sample with particle size of 150-250μm has the highest Langmuir volume.

关键词： particle size high-pressure methane adsorption coal shale gas

V_2O_5·nH_2O nanosheets and multi-walled carbon nanotube composite as a negative electrode for sodium-ion batteries

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Journal of Energy Chemistry 2019年第3期28卷 145-151页

作者： Ahmed S. Etman Junliang Sun reza Younesi Department of materials and Environmental Chemistry (mmK) Stockholm University Department of Chemistry Faculty of science Alexandria University College of Chemistry and molecular Engineering Peking University ?ngstr?m Advanced Battery Centre Department of Chemistry-?ngstr?m Laboratory Uppsala University

Two dimensional(2D) transition metal oxides and chalcogenides demonstrate a promising performance in sodium-ion batteries(SIBs) application. In this study, we investigated the use of a composite of freeze dried V_2O_5·nH_2O nanosheets and multi-walled carbon nanotube(mWCNT) as a negative electrode material for SIBs. Cyclic voltammetry(CV) results indicated that a reversible sodium-ion insertion/deinsertion into the composite electrode can be obtained in the potential window of 0.1–2.5 V vs. Na^+/Na. The composite electrodes delivered sodium storage capacities of 140 and 45 m Ah g^(-1) under applied current densities of 20 and 100 m A g^(-1), respectively. The pause test during constant current measurement showed a raise in the open circuit potential(OCP) of about 0.46 V, and a charge capacity loss of ～10%. These values are comparable with those reported for hard carbon electrodes. For comparison, electrodes of freeze dried V_2O_5·nH_2O nanosheets were prepared and tested for SIBs application. The results showed that the mWCNT plays a significant role in the electrochemical performance of the composite material.

关键词： Sodium-ion batteries Anode materials Vanadium pentoxide nanosheets Composite materials