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Tuning the electronic structure of the earth-abundant electrocatalysts for oxygen evolution reaction(OER)to achieve efficient alkaline water splitting-A review

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Journal of Energy Chemistry 2021年第5期30卷 299-342页

作者： mohammed-Ibrahim Jamesh moussab Harb Department of Physics and materials Science City University of Hong KongTat Chee AvenueKowloonHong KongChina Applied and Plasma Physics School of Physics(A28)University of SydneySydneyNSW 2006Australia KAUST Catalysis Center(KCC) Physical Sciences and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Tuning the electronic structure of the electrocatalysts for oxygen evolution reaction(OER)is a promising way to achieve efficient alkaline water splitting for clean energy production(H2).At first,this paper introduces the significance of the tuning of electronic structure,where modifying the electronic structure of the electrocatalysts could generate active sites having optimal adsorption energy with OER intermediates,and that could diminish the energy barrier for OER,and that could improve the activity for ***,this paper reviews the tuning of electronic structure along with catalytic performances,synthetic methodologies,chemical properties,and DFT calculations on various nanostructured earth-abundant electrocatalysts for OER in alkaline ***,this review discusses the tuning of the electronic structure of the several nanostructured earth-abundant electrocatalysts including oxide,(oxy)hydroxide,layered double hydroxide,alloy,metal phosphide/phosphate,nitride,sulfide,selenide,carbon containing materials,mOF,core-shell/hetero/hollow structured materials,and materials with vacancies/defects for OER in alkaline environment(including activity:overpotential(η)of ≤200 mV at10 m A cm^(-2);stability:≥100 h;durability:≥5000 cycles).Then,this review discusses the robust stability of the electrocatalysts for OER towards practical ***,this review discusses the in situ formation of thin layer on the catalyst surface during *** addition,this review discusses the influence of the adsorption energy of the OER intermediates on OER performance of the ***,this review summarizes the various promising strategies for tuning the electronic structure of the electrocatalysts to achieve enhanced performance for OER in alkaline environment.

关键词： OER electrocatalyst Electrochemical water splitting Earth abundant electrocatalyst Hydrogen energy

Role of ZnO-CeO_2 Nanostructures as a Photo-catalyst and Chemi-sensor

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Journal of materials Science & Technology 2011年第7期27卷 594-600页

作者： m. Faisal Sher Bahadar Khan mohammed m. Rahman Aslam Jamal Kalsoom Akhtar m.m. Abdullah Centre for Advanced materials and Nano-Engineering (CAmNE) and Department of Chemistry Faculty of Sciences and Arts Najran UniversityNajran 11001 Kingdom of Saudi Arabia Division of Nano Sciences and Department of Chemistry Ewha Womans UniversitySeoul 120-750 Korea

ZnO-CeO2 nanostructures were synthesized by simple and effcient low temperature method. The structure and morphology of the ZnO-CeO2 nanostructures were characterized by X-ray powder diffraction （XRD） and field emission scanning electron microscopy （FESEm）, which revealed elongated shaped CeO2 nanoparticles with diameters of 40–90 nm distributed on the surface of elongated ZnO nanostructures with diameters of 50–200 nm （edge–centre）. Further the structure of the synthesized ZnO-CeO2 nanostructure was supported by Raman spectra and Fourier transform infrared spectroscopy （FTIR）. UV-vis absorption spectrum was used to confirm the optical properties of the CeO2 doped ZnO nanostructures. Photo-catalytic activity of CeO2 doped ZnO nanostructure was evaluated by degradation of acridine orange and methylene blue which degraded 84.55% and 48.65% in 170 min, respectively. ZnO-CeO2 nanostructures also showed good sensitivity （0.8331 μA·cm-2·（mol/l）-1） in short response time （10 s） by applying to chemical sensing using ethanol as a target compound by I-V technique. These degradation and chemical sensing properties of ZnO-CeO2 nanostructures are of great importance for the application of ZnO-CeO2 system as a photo-catalyst and chemical sensor.

关键词： ZnO-CeO2 nanostructures Structural properties Optical properties Photocatalytic activity Ethanol sensing

Optimization of process parameters of friction welding of UNS S31803 duplex stainless steels joints

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Advances in manufacturing 2016年第1期4卷 55-65页

作者： m. mohammed Asif Kuikarni Anup Shrikrishna P. Sathiya Department of Production Engineering National Institute ofTechnology Tiruchirappalli 620015 Tamil Nadu India

This article presents an approach based on Taguchi method and Grey relational analysis to optimize process parameters of friction welding of UNS31803 duplex stainless steel. The main objective is to maximize mechanical properties like tensile strength, hardness and impact toughness and to minimize corrosion rate. Heating pressure, heating time, upsetting pressure and upsetting time were the four process parameters taken each at three levels. According to Taguchi quality design concept, an L9 orthogonal array was selected for experiments. The best combination of process parameters was found by both Taguchi method and Grey relational analysis. The influ- ence of the process parameters on overall quality charac- teristics of the friction welding process was evaluated by the analysis of variance （ANOVA） method. The confir- mation test results with optimal parameters confirmed the effectiveness of the proposed method in this study. Later, comparison was done between Taguchi method and Grey relational analysis on the basis of improvement in multi- response signal to noise （S/N） ratio over initial process parameters. Grey relational analysis was proved to be a better technique than Taguchi method for optimization of multiple responses.

关键词： Friction welding Duplex stainless steel Optimization Taguchi Grey relational analysis Analysisof variance (ANOVA)

Effect of microwave treatment on tensile properties of sugar palm fibre reinforced thermoplastic polyurethane composites

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Defence Technology（防务技术） 2018年第4期14卷 287-290页

作者： A.A.mohammed D.Bachtiar m.R.m.Rejab J.P.Siregar Structural materials and Degradation Focus Group Faculty of Mechanical EngineeringUniversity of Malaysia Pahang materials Engineering Department University of TechnologyBaghdadIraq

The effect of microwave treatment on the tensile properties of treated sugar palm fibre with 6% NaOH reinforced thermoplastic polyurethane composites was investigated. Firstly, the sugar palm fibres were treated by 6% alkali solution. Then, microwave treatment was used to treat the alkali treated sugar palm fibres. Three types of temperatures(i.e. 70, 80 and 90℃) were applied in microwave treatment. The extruder and hot press machines were used to mixing the sugar palm fibres and polyurethane resin, and fabricate the composites. Tensile properties(i.e. tensile strength, tensile modulus and elongation at break) were studied by following the ASTm D-638 standard. The highest tensile strength was recorded 18.42 mPa with microwave temperature at 70℃ and 6% alkali pre-treatment. Therefore, the temperature 70℃ of microwave treatment may consider the best degree cent grate.

关键词： Tensile properties Sugar palm fibre Thermoplastic polyurethane Alkali treatment microwave method

Application of advanced reproductive biotechnologies for buffalo improvement with focusing on Egyptian buffaloes

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Asian pacific Journal of Reproduction 2018年第5期7卷 193-205页

作者： Kamel m.E.mohammed Animal Reproduction Research Institute HaramGizaEgypt

many countries in the world consider the buffalo as a priority animal for the future, since it plays a pivotal role in human food sustainability. Even though Food and Agriculture Organization has termed the buffalo as an important undervalued asset, this species has yet to drive the same attention as cattle. Egypt has a wealth of buffaloes dispersed in small herds all over the country, so the efforts that have been made to improve their genetic background show little return. Contrarily, other countries concerned with buffalo improvement have already used a data recording system in buffalo herds, allowing to achieve a much faster improvement progress. This review intends to survey the existing information on the application of assisted reproduction techniques to improve buffalo productivity. The strength points that may help to improve buffalo production are identified, and the obstacles hindering the genetic improvement of Egyptian buffalo are characterized. Therefore, this work will gather information related to buffalo and compile it for an audience of researchers and specialists to enforce international collaboration for the development of buffalo production. Also, it will open the way for people interested in developing a future vision for buffalo potential, which will be helpful to close or minimize the biological gaps of buffaloes' researches.

关键词： Buffaloes Egypt Artificial insemination Embryo transfer Estrus synchronization Frozen semen Embryo freezing

Stress distribution from railway track over geogrid reinforced ballast underlain by clay

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 77-93页

作者： mohammed Y.Fattah mahmood R.mahmood mohammed F.Aswad Civil Engineering Department University of TechnologyBaghdad Iraq Civil Engineering Department University of TechnologyBaghdad IraqAssistant

Railway ballast forms a major component of a conventional rail track and is used to distribute the load to the subgrade, providing a smooth running surface for trains. It plays a significant role in providing support for the rail track base and distributing the load to the weaker layer underneath. Ballast also helps with drainage, which is an important factor for any type of transportation structure, including railroads. Over time, ballast progressively deforms and degrades under dynamic loading and loses its strength. In this study, extensive laboratory tests were conducted to investigate the effect of load amplitude, geogrid position, and number of geogrid layers, thickness of ballast layer and clay stiffness on the behavior of the reinforced ballast layer and induced strains in a geogrid. A half full-scale railway was constructed for carrying out the tests, which consisted of two rails 800 mm in length with three wooden sleepers(900 mm × 10 mm × 10 mm). Three ballast thicknesses of 200, 300 and 400 mm were used in the tests. The ballast was overlying 500 mm thickness clay in two states, soft and stiff. The tests were carried out with and without geogrid reinforcement; the tests were performed in a well-tied steel box of 1.5 m length ×1 m width ×1 m height. Laboratory tests were conducted to investigate the response of the ballast and the clay layers where the ballast was reinforced by a geogrid. Settlement in ballast and clay, soil pressure and pore water pressure induced in the clay were measured in reinforced and unreinforced ballast cases. It was concluded that the amount of settlement increased as the simulated train load amplitude increased, and there was a sharp increase in settlement up to cycle 500. After that, there was a gradual increase that leveled out between, 2500 to 4500 cycles depending on the frequency used. There was a slight increase in the induced settlement when the load amplitude increased from 0.5 to 1 ton but it was higher when the load am

关键词： ballast geogrid reinforcement clay stress pore water pressure dynamic load

Industrial Food Quality Analysis Using New k-Nearest-Neighbour methods

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Computers, materials & Continua 2021年第5期67卷 2681-2694页

作者： Omar Fetitah Ibrahim m.Almanjahie mohammed Kadi Attouch Salah Khardani Laboratory of Statistics and Stochastic Processes University of Djillali LiabesSidi Bel Abbes22000Algeria Department of mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia Facultédes sciences de Tunis Laboratoire des Réseaux Intelligents et NanotechnologieTunisTunisia

The problem of predicting continuous scalar outcomes from functional predictors has received high levels of interest in recent years in many fields,especially in the food *** k-nearest neighbor(k-NN)method of Near-Infrared Reflectance(NIR)analysis is practical,relatively easy to implement,and becoming one of the most popular methods for conducting food quality based on NIR *** k-NN is often named k nearest neighbor classifier when it is used for classifying categorical variables,while it is called k-nearest neighbor regression when it is applied for predicting noncategorical *** objective of this paper is to use the functional Near-Infrared Reflectance(NIR)spectroscopy approach to predict some chemical components with some modern statistical models based on the kernel and k-Nearest Neighbour *** this paper,three NIR spectroscopy datasets are used as examples,namely Cookie dough,sugar,and tecator ***,we propose three models for this kind of data which are Functional Nonparametric Regression,Functional Robust Regression,and Functional Relative Error Regression,with both kernel and k-NN approaches to compare between *** experimental result shows the higher efficiency of k-NN predictor over the kernel *** predictive power of the k-NN method was compared with that of the kernel method,and several real data sets were used to determine the predictive power of both methods.

关键词： Functional data analysis classical regression robust regression relative error regression kernel method k-NN method near-infrared spectroscopy

Empirical investigation to explore potential gains from the amalgamation of phase changing materials(PCms)and wood shavings

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能源与人工环境(英文) 2021年第3期2卷 315-326页

作者： Adham m.mohammed Amira Elnokaly Abdel monteleb m.Aly Department of Architecture Faculty of EngineeringUniversity of AssuitEgypt School of Architecture and the Built Environment University of LincolnUK

The reduction of gained heat,heat peak shifting,and the mitigation of air temperature fluctuations are some desirable properties that are sought after in any thermal insulation *** cannot be overstated that these fac-tors,in addition to others,govern the performance of such systems thus their effect on indoor ambient *** effect of such systems extends also to Heating,Ventilation and Air-conditioning(HVAC)systems that are set up to operate optimally in certain *** literature shows that PCms and natural materials such as wood-shavings can provide efficient passive insulation for buildings,it is evident that such approaches utilise methods that are of a degree of intricacy which require specialist knowledge and complex techniques,such as micro-encapsulation for *** technical and economic aspects in mind,an amalgam of PCm and wood-shavings has been created to be utilised as a feasible thermal *** amalgamation was performed in the simplest of methods,through submerging the wood shavings in *** experimental procedure was devised to test the thermal performance of the amalgam and compare this to the performance of the same un-amalgamated *** analysis revealed that no significant thermal gains would be expected from such ***,a significant reduction in the total weight of the insulation system would be achieved that,in this case,shown to be up to 20.94%.Thus,further reducing possible strains on structural elements due to the application of insulation on *** can be especially beneficial in vernacular architectural approaches where considerably large amounts and thicknesses of insulations are *** addition,cost reduction could be attained as wood shavings are significantly cheaper compared to the cost of PCms.

关键词： PCms Heat peak Heat peak shift Thermal performance Wood shavings By-products

Hypolipidemic effect of coffee silver skin in rats fed a high-fat diet

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Food Science and Human Wellness 2018年第4期7卷 252-259页

作者： Ayman mohammed El-Anany Rehab Farouk m.Ali Department of Special Food and Nutrition Researches Food Technology Research InstituteAgricultural Research CenterGizaEgypt Biochemistry Department Faculty of AgricultureCairo UniversityGizaEgypt Department of Food Science and Human Nutrition College of Agriculture and Veterinary MedicineAl-Qassum UniversityQassimSaudi Arab

The present study was conducted to evaluate the hypolipidemic effects of coffee silver skin(CSS)supplementation in rats fed a highfat diet(HFD).A total of 40 albino rats were used in the present *** groups were as follows:Rats fed a normal diet,N group;high fat diet,HFD group;high fat diet+10%CSS,HFD 10;HFD+15%CSS,HFD 15;HFD+20%CSS,HFD 20;the diets were followed for 8 *** samples were collected at the end of the *** the time of sacrifice,the weights of heart,liver,kidneys,epididymal fat and retroperitoneal fat of the experimental rats with respect to body weight were *** lipid parameter of the serum was recorded and liver and kidney function tests were ***,a histopathological assay was performed on the liver and kidney tissues of the rats fed the tested *** weight gain of the rats fed a HFD supplemented with 10,15 and 20%CSS was∼1.05,1.08 and 1.12 times lower than that of those rats fed HFD,*** incorporation of CSS at a level of 20%reduced the increase in liver,kidney,epididymal fat and retroperitoneal fat weight by 17.84,19.38,47.23 and 18.00%,respectively,compared with HFD *** administration induced considerable increases in alanine aminotransferase,aspartate aminotransferase and alkaline phosphatase activities compared with the control *** results also indicated that the HFD-fed rats exhibited increased levels of urea,uric acid and creatinine,by∼26.38,8.40 and 6.75%,respectively,compared with the control *** the exception of high-density lipoprotein cholesterol,all lipid fractions increased significantly in rats fed a *** administration of a HFD induced marked pathological changes in the liver and kidneys of the ***,the incorporation of various levels of CSS in to a HFD reduced these *** results of the present study illustrate that the incorporation of CSS into HFDs reduces the hyperlipidemia effect of these diets.

关键词： Hypolipidemic Coffee Fiber Biochemical Serum lipid