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Performance Evaluation of Calcium Alkali-treated Oil Palm/Pineapple Fibre/Bio-phenolic Composites

Journal of Bionic Engineering 2022年第5期19卷 1493-1503页

作者： Sameer A.Awad Hassan Fouad em.n m.khalaf n.Saba Hom n.Dhakal m.Jawaid Othman Y.Alothman Department of Chemistry School of Science and TechnologyUniversity of New EnglandArmidaleNSW 2351Australia Department of Chemistry College of Education for Pure ScienceUniversity of Al-AnbarRamadi 31001Iraq Biomedical Engineering Department Faculty of EngineeringHelwan UniversityHelwan 11792Egypt Pharmacy Department Al-Maarif University CollegeAnbar 3001 RamadiIraq Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400 SerdangMalaysia Advanced Polymers and Composites(APC)Research Group School of Mechanical and Design EngineeringUniversity of PortsmouthPortsmouth PO13DJUK Department of Chemical Engineering College of EngineeringKing Saud UniversityRiyadh 11433Saudi Arabia

The utilisation of oil palm fibre(OPF)and pineapple leaf fibres(PALF)as reinforcem.nt materials for bio-phenolic composites is growing especially in automotive lightweight *** major aim of this current study is to investigate the influence of alkali(Ca(OH)_(2)) treatment on pure and hybrid *** effects of enhancem.nts in chemical interactions were evaluated by the Fourier-Transform Infrared Spectrometer(FTIR).Dynamic mechanical Analysis(DmA)and Thermogravimetric Analysis(TGA)performance of untreated reinforcem.nts(OPF and PALF)and treated(OPF/OPF)composites at varying temperature and noted sufficient interfacial bonding contributing towards the improvem.nts in thermal *** DmA results,the storage modulus improved with treated composites while the damping factor was ***,the treated hybrid composites exhibited significant improvem.nts in thermal stability compared to untreated fibre *** results indicated that alkali calcium hydroxide(Ca(OH2(:T)incorporation in hybrid composites(OPF/PALF)results in increased tensile strength and modulus among all ***,the alkali-treated(Ca(OH)_(2))-treated pure composite(T/50%PALF),and hybrid composites(T/1OPF.1PALF)exhibited better flexural strength as compared with other *** contrast,the T/50%PALF showed higher flexural stress of 78.2 mPa,while the flexural modulus was recorded at 6503 *** can be proposed from the findings of this study that the alkali treatment(5%Ca(OH)_(2))can be utilised to improve the strength and efficiency of agriculture biomass to be used as reinforcem.nts in ***,the hybridisation of bio-fibre composites has the potential as a novel variety of biodegradable and sustainable composites appropriate for several industrial and engineering applications.

关键词： Hybrid fibre composites Alkali treatments Surface modifications mechanical properties Thermal stability

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Vibrational, rotational, and triaxiality features in extended O(6) dynamical symmetry of IBm using three-body interactions

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nuclear Science and Techniques 2020年第5期31卷 44-56页

作者： A.m.khalaf Azza O.El-Shal m.m.Taha m.A.El-Sayed Physics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt mathematics and Theoretical Physics Department Nuclear Research CenterAtomic Energy AuthorityCairo 13759Egypt

The shape transition between the vibrational U(5)and deformed c-unstable O(6)dynamical symmetries of sd interacting boson model has been investigated by considering a modified O(6)Hamiltonian,providing that the coefficients of the Casimir operator of O(5)are n-dependent,where n is the total number of *** modified O(6)Hamiltonian does not contain the number operator of the d boson,which is responsible for the vibrational *** addition,the deformation features can be achieved without using the SU(3)limit by adding to the O(6)dynamical symmetry the three-body interaction[QQQ]^(0),where Q is the O(6)symmetric quadrupole ***,triaxiality can be generated through the inclusion of the cubic d-boson interaction[d+d+d+]^(3)·∣ddd∣^(3).The classical limit of the potential energy surface(PES),which represents the expected value of the total Hamiltonian in a coherent state,is studied and *** modified O(6)model is applied to the even–even^124-132 Xe *** parameters for the Hamiltonian and the PESs are calculated using a simulated search program to obtain the minimum root mean square deviation between the calculated and experimental excitation energies and B(E2)values for a number of low-lying levels.A good agreem.nt between the calculations and experiment results is found.

关键词： nuclear structure Extended O(6)of IBm Three-body interactions Coherent state

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new Antenna Array Beamforming Techniques Based on Hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa m.Amer Ashraf A.m.khalaf Amr H.Hussein Salman A.Alqahtani mostafa H.Dahshan Hossam m.Kassem Electronics and Communications Engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer Engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the elem.nt’s excitations while the GA optimizes the elem.nt *** m elem.nts linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length n=(2m−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths m,m−1,andm,*** the same elem.nt spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(HPBW).While the middle excitations give the same HPBWas the original LAA with a relatively higher *** the increased HPBWof the odd and even excitations,the elem.nt spacing is optimized using the ***,the synthesized arrays have the same HPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforem.ntioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider HPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(HPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

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Preparation and Characterization of Oligomer from Recycled PET and Evaluated as a Corrosion Inhibitor for C-Steel material in 0.1 m HCl

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Open Journal of Organic Polymer materials 2017年第1期7卷 1-15页

作者： Ali H. Yasir Alaa S. khalaf moayad n. khalaf Chemistry Department College of Science Basrah University Basrah Iraq

Polyethylene terephthalate waste (PET) was depolymerized by thiodiglycol into thioglycolyzed product. The product was characterized by FTIR and 1HnmR spectroscopy and the thermal properties (TGA, DTA) showed that the prepared compound was thermally stable until 250°C. The efficiency of the prepared corrosion inhibitor for carbon steel was measured by using acid media (0.1 HCl) as corrosive environment and the inhibitor concentration was (0, 10, 20, 30, 40 and 50 ppm). The electrochemical technique used Tafel plot to measure the efficiency of inhibitor. Factors effect on the rate of corrosion like temperature (298, 308, 318, 328 K) and concentration (10, 20, 30, 40, 50 ppm) of inhibitor were studied. From the obtained results many factors were calculated that determined the efficiency of the inhibitor like corrosion rate, charge transfer resistance and inhibitor efficiency. It was observed that the corrosion rate and charge transfer of the carbon steel for the inhibitor increase with increase of temperature and decrease with increase of the inhibitor concentration in the same temperature. The results showed that the inhibitor had high inhibition in reducing the corrosion rate. The inhibition efficiency (% IE) reached 97.1% for the 40 ppm concentration at 308 K.

关键词： Waste Polymer Glycolysis Corrosion Inhibitor

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High Performance Oil Resistant Rubber

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Open Journal of Organic Polymer materials 2012年第4期2卷 89-94页

作者： A. I. khalaf A. A. Yehia m. n. Ismail H. El-Sabbagh Department of Polymers and Pigments National Research Center Cairo Egypt

Blending of polymers has gained much interest due to the fact that, it can be used to produce new polymeric materials with specific properties suitable for some special applications. The blends from acrylonitrile butadiene rubber (nBR), chloroprene rubber (CR) and polyvinyl chloride (PVC) has been designed for products working in contact with oils. The characteristics of the designed blends either binary blends (nBR/PVC or PVC/CR) or ternary blends (nBR/ PVC/CR) were investigated by rheological properties, mechanical analysis and swelling in oil and toluene. It was found that the incorporation of PVC in the blend compositions leads to the decrease in degree of swelling, the penetration rate and the average diffusion coefficient. On the other hand the ultimate tensile strength (UTS), the hardness and strain energy were increased. This was attributed to the plastic nature of PVC, beside its additional behavior as filler. The crosslinking density in the blend vulcanizates under investigations was determined by Flory-Rehner and mooney-Rivlin [Stress/Strain] equations. The higher values of crosslinking density determined by mooney-Rivlin can be attributed to the additional physical crosslinks (e.g. entanglem.nts etc), beside the chemical crosslinks determined by swelling in toluene. This study showed that nBR/PVC blends are characterized with high performance oil resistant, which can be recommended to automotive industry.

关键词： Blends nBR PVC CR Oil Resistant Thermal Ageing Rheology Strain Energy

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Flow over Broad Crested Weirs： Comparison of 2D and 3D models

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Journal of Civil Engineering and Architecture 2017年第8期11卷 769-779页

作者： Shaymaa A. m. Al-Hashimi Huda m. madhloom Rasul m. khalaf Thameen n. nahi nadhir A. AI-Ansari Department of Civil Engineering Al-Mustansiriayah University Baghdad 1001Iraq Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology 97187 Lulea Sweden

The flow over broad-crested weirs was simulated by computational fluid dynamic model. The water surface profile over broad crested weir was measured in a laboratory model and validated using two and three dimensional Fluent programs. The Reynolds Averaged navier-Stokes equations coupled with the turbulent standard （k-ε） model and volume of fluid method were applied to estimate the water surface profile. The results of numerical model were compared with experimental results to evaluate the ability of model in describing the behaviour of water surface profile over the weir. The results indicated that the 3D required more time in comparison with 2D results and the flow over weir changed from subcritical flow at the upstream （U/S） face of weir to critical flow over the crest and to supercritical flow at downstream （D/S）. A reasonable agreem.nt was noticed between numerical results and experimental observations with mean error less than 2 %.

关键词： Broad-crested weir discharge coefficient subcritical flow numerical CFD Fluent.

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Elastically restrained Bernoulli-Euler beams applied to rotary machinery modelling

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Acta mechanica Sinica 2011年第1期27卷 56-62页

作者： Tiago A.n.Silva nuno m.m.maia ISEL Polytechnic Institute of LisbonDepartment of Mechanical EngineeringRua Conselheiro Emídio Navarro IDmEC-IST Technical University of LisbonDepartment of Mechanical Engineering

Facing the lateral vibration problem of a machine rotor as a beam on elastic supports in bending,the authors deal with the free vibration of elastically restrained Bernoulli-Euler beams carrying a finite number of concentrated elem.nts along their *** on Rayleigh’s quotient,an iterative strategy is developed to find the approximated torsional stiffness coefficients,which allows the reconciliation between the theoretical model results and the experimental ones,obtained through impact *** mentioned algorithm treats the vibration of continuous beams under a determined set of boundary and continuity conditions, including different torsional stiffness coefficients and the effect of attached concentrated masses and rotational inertias, not only in the energetic terms of the Rayleigh’s quotient but also on the mode shapes,considering the shape functions defined in *** loading cases are examined and examples are given to illustrate the validity of the model and accuracy of the obtained natural frequencies.

关键词： Transverse vibration of beams · Elastic supports · Torsional stiffness coefficients

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Pion emission in α-particle interactions with various targets of nuclear emulsion detector

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Chinese Physics C 2015年第9期39卷 35-42页

作者： A.Abdelsalam Z.Abou-moussa n.Rashed B.m.Badawy H.A.Amer W.Osman m.m.El-Ashmawy n.Abdallah Physics Department Faculty of Science Cairo University mohamed El-nadi High Energy Lab Faculty of Science Cairo University Physics Department Faculty of Science Fayoum University Reactor Physics Department Nuclear Research Center Atomic Energy Authority nuclear and Radiological Regulatory Authority NRRA

The behavior of relativistic hadron multiplicity for 4He-nucleus interactions is investigated. The experi- ment is carried out at 2.1 A and 3.7 A GeV （Dubna energy） to search for the incident energy effect on the interactions inside different emulsion target nuclei. Data are presented in terms of the number of emitted relativistic hadrons in both forward and backward angular zones. The dependence on the target size is presented. For this purpose the statistical events are discriminated into groups according to the interactions with H, CnO, em, and AgBr target nuclei. The separation of events, into the mentioned groups, is executed based on Glauber＇s multiple scattering theory approach. Features suggestive of a decay mechanism seem to be a characteristic of the backward emission of relativistic hadrons. The results strongly support the assumption that the relativistic hadrons may already be emitted during the de-excitation of the excited target nucleus, in a behavior like that of compound-nucleus disintegration. Regarding the limiting fragmentation hypothesis beyond 1 A GeV, the target size is the main parameter affecting the backward production of the relativistic hadron. The incident energy is a principal factor responsible for the forward relativistic hadron production, implying that this system of particle production is a creation system. However, the target size is an effective parameter as well as the projectile size considering the geometrical concept regarded in the nuclear fireball model. The data are analyzed in the framework of the FRITIOF model.

关键词： α-particle interactions at Dubna energies shower particle sources target size dependence FRITIOFmodel

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Effect of Using magnetic Brackish Water on Irrigated Bell Pepper Crop （Capsicum annuum L.） Characteristics in Lower Jordan Valley/West Bank

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Journal of Agricultural Science and Technology(A) 2014年第10期4卷 830-838页

作者： Amer marei Dia Rdaydeh Dia Karajeh nawaf Abu-khalaf Water and Environmental Research Lab Faculty of Science and Technology Al-Quds University (AQU) P.O. Box 20002 EastJerusalem Occupied Palestinian Territory USAID-Ramallah office- West Bank Occupied Palestinian Territory Technical and Applied Research Center (TARC) Palestine Technical University-Kadoorie (PTUK) P. O. Box 7 TulkarmOccupied Palestinian Territory

Increasing salinity of the groundwater is one of major challenges faced by agricultural sector in West Bank/Palestine. This study was carried out in the Lower Jordan Valley （LJV） under greenhouse field condition, where an area of 0.12 ha was irrigated with 3.5 dS/m magnetic treated water during the growing season 2012/2013. The results of this pilot project show that there are significant increases in the yield of red and yellow bell pepper of about 20% and 18% on fresh weight basis, respectively. Water use efficiency increased by 15% and an increase in shelf time of 7 d were also recorded. The chlorophyll content raised significantly in the leaves of treated plants compared to the controlled one by 2.5 mg/g. Bell pepper irrigated with magnetic water produces 37% more four champers than that of the controlled one. On the other hand, there were no clear significant effects on the height of the plant, number of fruits, distance between nods, size of fruits, number and thickness of walls and sugar contents. Applying visible/near infrared （VIS/n｜R） spectroscopy test shows that it is possible to distinguish between treated and controlled bell pepper fruits. multivariate data analysis （mVDA） method was used to test the classification of chemical elem.nts in the fruit and it was found that treated and controlled fruit samples are divided into two groups according to their water treatment. An increase in all nutrient concentrations was found in fruits irrigated with magnetic treated water compared with the controlled one. Further testing is needed especially by involving other variables such as decreasing the volume of irrigated water and fertilizers.

关键词： magnetic water brackish groundwater bell pepper yield-quality shelf time Palestine.

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Fish assemblages in seagrass habitat along the Jordanian coast of the Gulf of Aqaba

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natural Science 2012年第8期4卷 517-525页

作者： maroof A. khalaf Saber Al-Rousan Fuad A. Al-Horani Department of marine Biology Faculty of Marine Sciences The University of Jordan-Aqaba Aqaba Jordan marine Science Station The University of Jordan Aqaba Jordan

The spatial distribution and community structure of the fishes were studied at different depths and sites along the Jordanian coast in seagrass habitat. A total of 37,034 fishes were counted representing 132 species belonging to 35 families observed during visual census in three sites (average of 4741.6 fish per transect). Out of the 132 species encountered, 5 species of them including neopomacentrus miryae Lethrinus borbonicus, Pseudanthias squamipinnis, Lethrinus variegatus, Siganus rivulatus accounted for 57.7% of all individuals. Fishes were most abundant and significantly higher at 12 m depths (mean n = 2889.6) in comparison with shallow 6m depth (mean = 1225.3 with (p = 0.0218). This may be attributed to many plank-tivorous fishes that inhabit this depth such as P. squampinnis, Paracheilinus octotaenia, Chromis pelloura, Decapterus macarellus, and Cirrhilabrus rubriventralis probably with high abundance of plankton at 12 m depth than 6 m. The number of species was significantly higher in Phosphate Loading Berth (PLB;mean S = 54.7) than in Hotels area site (HA;mean S = 12.8) with (p = 0.0002) and Tala Bay site (TB;mean S = 31) with (p = 0.0484). This may be due to higher hard coral cover at Phophate Loading Berth.

关键词： Fish Assemblages Seagrass Habitat Gulf of Aqaba Red Sea

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