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SYNTHESIS AND CHARACTERIZATION OF A METHACRYLATE POLYMER WITH SIDE CHAIN KETONE AND ITS DERIVATIVES

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Chinese Journal of Polymer Science 2011年第1期29卷 101-110页

作者： ibrahim Erol Cemal Cifci Department of Chemistry Faculty of Arts and ScienceUniversity of Afyon KocatepeAfyonkarahisarTurkey

A new type of methacrylate monomer, 2-（4-benzoylphenoxy）-2-oxoethyl methylacrylate （BOEMA） was synthesized. The radical homopolymerization of BOEMA was performed at 65℃ in a 1,4-dioxane solution with benzoyl peroxide as an initiator. The oxime and thiosemicarbazone derivatives of poly[2-（4-benzoylphenoxy）-2-oxoethyl methylacrylate] poly（BOEMA） were prepared with hydroxylamine hydrochloride, and thiosemicarbazone hydrochloride, respectively. The monomer and its homopolymer were characterized with Fourier transform infrared and NMR techniques. The thermal stabilities of poly（BOEMA） and its derivatives were investigated with thermogravimetric analysis and differential scanning calorimetry. The ultraviolet stability of the polymers was compared. The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi. The activation energies of the thermal degradation of the polymers were calculated with the Ozawa and Kissinger methods.

关键词： Acetyl group Ethylene dimethacrylate Oxime Thermal stability Biological activity Activation energies

Laterites-bearing REEs,Wadi Natash,Southeastern Desert,Egypt

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Journal of Rare Earths 2010年第3期28卷 471-476页

作者： Mohamed El-Ahmady ibrahim Nuclear Materials Authority P.O.Box530EL MaadiCairoEgypt

The present paper recorded the occurrence of laterites-bearing REEs in Natash *** laterite deposits occur as horizons(5-15 m in thickness) at the boundary between the Cretaceous sandstones,and Natash *** was recorded in more than twenty six occurrence distributed over an area of about 500 km2 along and around Wadi *** ranges in color from light-grey,dark-grey to *** distribution of laterite deposits is structural *** results of laterites proved the...

关键词： Natash flows laterites clay minerals REEs

A comparison between powders and thin films of single-walled carbon nanotubes for the adsorption behaviors of phenylalanine and glycine by XANES study

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Science China(Physics,Mechanics & Astronomy) 2010年第8期53卷 1449-1452页

作者： ibrahim Kurash Institute of High Energy Physics Chinese Academy of Sciences

We have compared the adsorption behaviors between single-walled carbon nanotube (SWCNT) powders and thin films with amino acids such as phenylalanine and glycine by using the X-ray absorption near edge structure (XANES) spectroscopy. On SWCNT powders very weak adsorption occurs as confirmed also by studies at high solution concentrations. The comparison of the adsorption behaviors with previous reports for thin films of SWCNTs shows that, due to their compact structure, thin films favor the adsorption of amino acids and represent themselves good candidate for a reliable evaluation of the interaction among amino acids and SWCNTs.

关键词： carbon nanotubes XANES amino acids

Wear properties of copper and copper composites powders consolidated by high-pressure torsion

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Friction 2020年第2期8卷 433-450页

作者： Mohamed ibrahim Abd El AAL Mechanical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addawaser 11991Saudi Arabia Mechanical Design&Production Department Faculty of EngineeringZagazig UniversityZagazig 44519Egypt

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion(HPT)were *** HPT processed(HPTed)samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness,reasonable ductility level,and high wear *** wear mass loss and coefficient of friction of HPTed samples were remarkably lower than that of cold-compacted and sintered samples as well as that of micro and nano Cu and Cu-SiC composites from previous *** sample fabrication method has an apparent influence on the wear *** wear mechanism was converted from adhesive,delamination,three-body mechanism,grooves(take off the SiC particles),and cracks into abrasive wear after *** can be considered a dominant wear mechanism in all *** worn surface morphology and analysis support the relationship between wear mechanism and characteristics.

关键词： Cu-SiC composite powders high-pressure torsion(HPT) fine and coarse grains wear characteristics worn surface morphology

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

Geological, Engineering Geological and Hydrogeological Characteristics of the Knowledge Economic City, Al Madinah Al Munawwarah, KSA

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Geomaterials 2025年第1期15卷 40-55页

作者： Mutasim A. M. Ez Eldin Tareq Saeid Al Zahrani Gabel Zamil Al-Barakati ibrahim Mohamed AlHarthi Marwan Mohamed Al Saikhan Waleed Abdel Aziz Al Aklouk Waheed Mohamed Saeid Ba Amer Programme of Engineering Geology Center of Applied Geology Saudi Geological Survey Jeddah Kingdom of Saudi Arabia Department of Engineering Geology College of Petroleum Geology and Minerals University of Bahri Khartoum Sudan Zamzam Studies and Research Center Saudi Geological Survey Jeddah Kingdom of Saudi Arabia

The Knowledge Economic City (KEC) of Al Madinah Al Munawwarah is one of the major projects and represents the cornerstone for the new development activities for Al Madinah. The study area contains different geological units dominated by basalt and overlain by surface deposits. The surface soils vary in thickness and can be classified into well-graded SAND with silt and gravel (SW-SM), silty SAND with gravel (SM), silty GRAVEL with sand (GM), and sandy SILTY clay (CL-ML). The subsurface soil obtained from the drilled boreholes can be classified into poorly graded GRAVEL (GP), well-graded GRAVEL with sand (GW), poorly graded GRAVEL with silt (GP-GM), silty CLAYEY gravel with sand (GC-GM), silty SAND with gravel (SM), silt with SAND (ML), and silty CLAY with sand (CL-ML), sandy lean CLAY (CL), and lean CLAY (CL). The relative density of the deposit and the different gravel sizes intercalated with the soil influenced the Standard Penetration Test (SPT) values. The SPT N values are high and approach refusal even at shallow depths. The shallow refusal depth (0.10 to 0.90 m) of the Dynamic Cone Penetration Test (DCPT) was observed. Generally, the soil can be described as inactive with low plasticity and dense to very dense consistency. The basalt of the KEC site is characterized by slightly (W2) to highly (W4) weathering, their strength ranges from moderate (S4) to very strong (S2), and the Rock Quality Designation (RQD) ranges from very poor (R5) to excellent (R1). The engineering geological map of the KEC characterized the geoengineering properties of the soil and rock materials and classified them into many zones. The high sulphate (SO42−) and chloride (Cl−) contents in groundwater call for protective measures for foundation concrete. The current study revealed that geohazard(s) mitigation measures concerning floods, volcanic eruptions, and earthquakes should be considered.

关键词： Engineering Geology Knowledge Economic City Petrographic Description Rock and Soil Investigations

Socio-Economic Characteristics of Lagoon Cattle Farmers in Côte d’Ivoire

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Agricultural Sciences 2025年第1期16卷 206-214页

作者： Brahima Soro Yves Stéphane Aka Sylvain Zadi Bopo Herbert Michael Kpahé Kanh Abdoul-Razak Songuida Koné ibrahim Bakayoko Patricia Danielle Adjo Gnandji Mathurin Koffi N’goran Paulin Didier Sokouri Laboratory of Biotechnology Agriculture and Valorisation of Biological Resources UFR Biosciences Flix Houphout-Boigny University Abidjan Cte dIvoire Department of Biochemistry and Genetics Peleforo Gon Coulibaly University Korhogo Cte dIvoire Ministry of Animal and Natural Resources Abidjan Cte dIvoire Genetics and Molecular Epidemiology Research Unit Biodiversity and Management of Tropical Ecosystems Laboratory UFR Environment Jean Lorougnon Gud University Daloa Cte dIvoire

This study examines the socio-economic profile of livestock farmers in coastal Côte d’Ivoire. A total of 43 people were interviewed using well-structured questionnaires. The collected data were analyzed using descriptive methods. The results showed that local Lagoon breeders are divided into two zones: southwest and southeast. Breeders in the south-western region are generally located in two sub-prefectures of the Tabou Department (Grabo and Oulodio). Tabou’s department alone accounts for 42% of the Lagoon breed in Côte d’Ivoire. Agriculture in this area is traditionally sedentary, practiced for social reasons. On the other hand, the south-eastern zone, located in the departments of Aboisso, Adzopé, Agboville, Grand-Lahou, Jacqueville, Abidjan, Dabou and Sikensi, represents 58% of the Lagoon breeding area in Côte d’Ivoire. This second group is characterised by improved breeding. Most of the farmers interviewed in this zone breed for economic reasons. However, the risk of cross-breeding, which already affects the local Lagoon breed, could be increased by the presence of other species such as the Zebu and Ndamas, or even the Baoulé, in this south-eastern herd.

关键词： Socio-Economic Côte d’Ivoire Breeding Lagoon Cattle Farmers

Two-Fold and Symmetric Repeatability Rates for Comparing Keypoint Detectors

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Computers, Materials & Continua 2022年第12期73卷 6495-6511页

作者： ibrahim El rube’ Department of Computer Engineering CCITTaif UniversityTaif21944Saudi Arabia

The repeatability rate is an important measure for evaluating and comparing the performance of keypoint *** repeatability rate measurementswere used in the literature to assess the effectiveness of keypoint *** these repeatability rates are calculated for pairs of images,the general assumption is that the reference image is often known and unchanging compared to other images in the same ***,these rates are asymmetrical as they require calculations in only one *** addition,the image domain in which these computations take place substantially affects their *** presented scatter diagram plots illustrate how these directional repeatability rates vary in relation to the size of the neighboring region in each pair of ***,both directional repeatability rates for the same image pair must be included when comparing different keypoint *** paper,firstly,examines several commonly utilized repeatability rate measures for keypoint detector *** researcher then suggests computing a two-fold repeatability rate to assess keypoint detector performance on similar scene ***,the symmetric mean repeatability rate metric is computed using the given two-fold repeatability ***,these measurements are validated using well-known keypoint detectors on different image groups with various geometric and photometric attributes.

关键词： Repeatability rate keypoint detector symmetric measure geometric transformation scatter diagram

New Improved Ranked Set Sampling Designs with an Application to Real Data

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Computers, Materials & Continua 2021年第5期67卷 1503-1522页

作者： Amer ibrahim Al-Omari ibrahim M.Almanjahie Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraqJordan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia

This article proposes two new Ranked Set Sampling(RSS)designs for estimating the population parameters:Simple Z Ranked Set Sampling(SZRSS)and Generalized Z Ranked Set Sampling(GZRSS).These designs provide unbiased estimators for the mean of symmetric *** is shown that for non-uniform symmetric distributions,the estimators of the mean under the suggested designs are more efcient than those obtained by RSS,Simple Random Sampling(SRS),extreme RSS and truncation based RSS ***,the proposed RSS schemes outperform other RSS schemes and provide more efcient estimates than their competitors under imperfect *** suggested mean estimators under perfect and imperfect rankings are more efcient than the linear regression estimator under *** proposed RSS designs are also extended to cover the estimation of the population *** data is used to examine wthe usefulness and efciency of our estimators.

关键词： Ranked set sampling unbiased estimator simple random sampling mean squared error efciency imperfect ranking