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Insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： Mohamed Mobarak Saleh Qaysi Mohamed saad Ahmed Yasser F.Salama Ahmed Mohamed Abbass Mohamed abd Elrahman Hamdy Aabdel-Gawwad Moaaz K.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building Materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building Materials and Processing Technology Research Institute Housing and Building National Research Center(HBRC)CairoEgypt Faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)*** studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled *** Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical *** number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all *** increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic ***,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,*** internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC *** results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal Magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters

Gamma induced changes in Makrofol/CdSe nanocomposite films

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Chinese Physics B 2022年第9期31卷 547-553页

作者： Ali A.Alhazime M.ME.Barakat Radiyah A.Bahareth E.M.Mahrous saad Aldawood S.abd El Aal S.A.Nouh Physics Department Faculty of ScienceTaibah UniversityMedinaSaudi Arabia Department of Physics Faculty of ScienceTaibah UniversityYanbuSaudi Arabia Department of Physics Faculty of ScienceAlexandria UniversityAlexandriaEgypt Physics Department College of ScienceJeddah UniversityJeddahSaudi Arabia Department of Physics and Astronomy College of ScienceP.O.BOX 2455King Saud UniversitySaudi Arabia Center of Radiation Research and Technology Egyptian Atomic AuthorityNasr CityCairoEgypt Qassim University P.B.6644Buraidah 51452QassimSaudi Arabia Physics Department Faculty of ScienceAin Shams UniversityCairoEgypt

We applied an ex-situ casting procedure to prepare a nanocomposite(NCP)from Makrofol polycarbonate(PC)and CdSe *** CdSe nanoparticles were prepared by a thermolysis procedure in the presence of N_(2) gas *** refinement of x-ray data illustrated that the CdSe adopts a cubic zinc blend structure of 6.057 A lattice parameter and 2 nm typical grain *** from the prepared NCP were exposed to γ dosages(20 kGy-250 kGy).The modifications induced in the NCP films owing to γ dosages have been ***γirradiation(50 kGy-250 kGy)causes crosslinks that reduce the optical bandgap from 4.15 eV to 3.81 eV,associated with an increase in dielectric parameters and refractive *** is attributed to an increase in the mass fraction of the disordered regions as specified by x-ray *** PC-CdSe NCP was found to have a reaction to color modification which makes it suitable for saleable reproduction on a printing press.

关键词： gamma nanocomposite x-ray dfraction UV spectra color changes

Fibrinogen Levels in Hypertensive and Normotensive: A Cross-Sectional Study from El-Obied City, Sudan

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Journal of Biosciences and Medicines 2016年第2期4卷 28-32页

作者： Ahmed abdalla Agab Eldour Tarig Osman Khalafallah Hassan Mohammed Noja Eltayib Siddig Mohammed saad Mohieldin Elsayid Asaad Mohammed Ahmed abd allah Babker Faculty of Medicine and Health Science Medical Laboratory Science Program University of Kordofan El-Obied Sudan Future Lab Medical Laboratories Co. Ltd. Al Kharj KSA Departments of Clinical Laboratory Sciences College of Applied Medical Sciences King Saud Bin Abdulaziz University for Health Sciences Riyadh KSA Department of Medical Laboratory Science Al-Ghad International College for Health Sciences Al-Madinah Al-Monawarah KSA

Hypertension (HTN) has been defined as a blood pressure level at which an otherwise healthy person would have an increased risk of cardiovascular disease that could be mitigated through blood pressure-lowering treatment. Worldwide, hypertension is one of the most common causes of death. The prevalence of hypertension and cardiovascular disease increases with age, and has been found to be higher in those of South Asian and African ancestry, and in Aboriginal populations. Hypertension is not only one of the most important risk factors for cardiovascular disease, but also the number one modifiable risk factor for stroke. Alterations in blood coagulation system have been reported in patients of hypertension. Fibrinogen has been identified as a major independent risk factor for cardiovascular diseases. This was a descriptive cross-sectional study, conducted in Elobied teaching hospital during period from March to June 2014. The aim of this study is to determine the level of fibrinogen among hypertensive patients. Seventy percent of the patients (about 35 patients) had high fibrinogen level above 400 mg/dl compared with the control and about 30% (15 patients) were within the normal range of 200 mg - 400 mg/dl. This study has concluded that there was a significant increase in fibrinogen level in hypertensive patients compared to control, while the gender has no effect on the level of fibrinogen.

关键词： Hypertensive Normotensive Fibrinogen Level El-Obied City Sudan

Continued Fraction Evaluation of the Universal Y’s Functions

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International Journal of Astronomy and Astrophysics 2015年第1期5卷 15-19页

作者： Mohammed Adel Sharaf abdel-naby saad saad Nihad saad abd El Motelp Department of Astronomy Faculty of Science King Abdulaziz University Jeddah KSA Department of Astronomy National Research Institute of Astronomy and Geophysics Cairo Egypt Department of Mathematics Preparatory Year Qassim University Buraidah KSA Department of Mathematics Preparatory Year for Girls Branch Hail University Hail KSA

In the present paper, an efficient algorithm based on the continued fractions theory was established for the universal Y’s functions of space dynamics. The algorithm is valid for any conic motion (elliptic, parabolic... 详细信息

关键词： Universal Kepler Equation Continued Fraction Technique Y-Universal Function

Efficient Hardware Design of a Secure Cancellable Biometric Cryptosystem

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Intelligent Automation & Soft Computing 2023年第4期36卷 929-955页

作者： lamiaa A.Abou Elazm Walid El-Shafai Sameh Ibrahim Mohamed G.Egila H.Shawkey Mohamed K.H.Elsaid Naglaa F.Soliman Hussah Nasser AlEisa Fathi E.abd El-Samie Department of Microelectronics Electronics Research InstituteAlnozhaEgypt Department of Electronics and Electrical Communications Engineering Ain Shams UniversityCairoEgypt Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh 11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Biometric security is a growing trend,as it supports the authentication of persons using conﬁdential biometric *** of the transmitted data in multi-media systems are susceptible to attacks,which affect the security of these *** systems provide sufﬁcient protection and privacy for *** recently-introduced cancellable biometric recognition systems have not been investigated in the presence of different types of *** addition,they have not been studied on different and large biometric *** point that deserves consideration is the hardware implementation of cancellable biometric recognition *** paper presents a suggested hybrid cancellable biometric recognition system based on a 3D chaotic *** rationale behind the utilization of the 3D chaotic cryptosystem is to guarantee strong encryption of biometric templates,and hence enhance the security and privacy of *** suggested cryptosystem adds signiﬁcant permutation and diffusion to the encrypted biometric *** introduce some sort of attack analysis in this paper to prove the robustness of the proposed cryptosystem against *** addition,a Field Programmable Gate Array(FPGA)implementation of the pro-posed system is *** obtained results with the proposed cryptosystem are compared with those of the traditional encryption schemes,such as Double Random Phase Encoding(DRPE)to reveal superiority,and hence high recogni-tion performance of the proposed cancellable biometric recognition *** obtained results prove that the proposed cryptosystem enhances the security and leads to better efﬁciency of the cancellable biometric recognition system in the presence of different types of attacks.

关键词： Information security cancellable biometric recognition systems cryptanalysis 3D chaotic map encryption FPGA

The Diagnostic Role of Brain MRI in Detection of Multiple Sclerosis Related Cognitive Impairment

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Journal of Behavioral and Brain Science 2019年第8期9卷 313-324页

作者： Mohamed saad Maha Bilal Wael Gabr Aymen abd Elnaby Neurology Department Mansoura University Mansoura Egypt Radiology Department Mansoura University Mansoura Egypt Internal Medicine Department Tiabah University Madina KSA

Background: Cognitive impairment (CI) is a common manifestation of multiple sclerosis (MS), which can severely affect patients’ and their families’ life. Early suspicion and detection of CI can improve general medical management of MS patients. Objectives: To correlate MS related CI to cortical brain lesions using brain magnetic resonance imaging (MRI). Materials and Methods: Cognitive impairment was detected using mini mental state examination (MMSE);Neurological examination and brain MRI were performed for all patients. Correlation was calculated between disease cortical burden detected by MRI and CI. Results: Fifty-three patients with proven MS were scanned by brain MRI;69.8% of them had cognitive impairment diagnosed with MMSE. The presence and severity of cognitive impairment was correlated to cortical brain lesion. Cognitive impairment was not correlated with non-cortical brain lesions or neurological physical disability measured by Expanded Disability Status Scale (EDSS). Conclusions: Presence of brain frontal cortical lesions detected by MRI in MS patients can predict subsequent development of MS-related CI.

关键词： Multiple Sclerosis Cognitive Impairment MRI Cortical Brain Lesion MS Related CI

Maximum Power Point Tracker Controller Using Fuzzy Logic Control with Battery Load for Photovoltaics Systems

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Smart Grid and Renewable Energy 2021年第10期12卷 163-181页

作者： Mazen Yeselam Baramadeh Mohamed abd Almonem Abouelela saad Mubarak Alghuwainem Electrical Engineering Department King Saud University Riyadh Saudi Arabia

The target of this paper is to model a Maximum Power Point Tracker (MPPT) using a Fuzzy Logic Control (FLC) algorithm and to investigate its behavior with a battery load. The advantage of this study over other studies in this field is that it considers a battery load rather than the commonly used resistive load especially when we deal with the relationship between MPPT and system load. The system is about 60 kW which is simulated under various environmental conditions by Matlab/Simulink program. For this type of non-linear application, FLC naturally offers a superior controller for the real load case. The artificial intelligence approach also benefits from this method for overcoming the complexity of nonlinear system modelling. The results show that FLC provides high performance for MPPT of PV system with battery load due to its low settling time and limited oscillation around the steady state value. These are assistant factors for increasing battery life.

关键词： MPPT Controller Fuzzy Logic Control PV System Matlab Simulink

Natural radioactivity levels and radiation hazards for gypsum materials used in Egypt

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Natural Science 2014年第1期6卷 5-13页

作者： Ahmed Hassan Korna Soad saad Fares Magda abd El-Rahman Department of Physics Faculty of Science Al Baha University Al Bahah KSA Department of Radiation Physics National Center of Radiation Research and Technology NCRRT Atomic Energy Authority Cairo Egypt

Radionuclides naturally occurring in building materials may significantly contribute to the annual doses to the public. For instance, familiar building materials such as the concrete and gypsum board have been reported to produce a dose of about 0.04 mSv per year for a typical person (NCRP 1987c). External as well as internal exposures are two pathways of radiation dose imparted to human beings from the building materials. As information on the radioactivity of such materials is lacking, the study of gypsum materials used in Egypt was carried out in order to estimate the annual dose to the Egyptian population due to natural radionuclides in building materials. During the study, 18 samples of commonly used gypsum raw materials were collected and measured. The activity concentrations were determined by gamma ray spectrometry. Their mean values were in the ranges of 499.29 ± 11.53 Bq·kg-1 for 40K, 91.97 ± 2.61 Bq·kg-1 for 226Ra, 37.62 ± 1.67 Bq·kg-1 for 238U and 42.27 ± 2.22 Bq·kg-1 for 232Th. The activity indexed Iγ for 18, different gypsum samples varied from 0.31 ± 0.03 to 2.3 ± 0.19 and the radium equivalent activity (Raeq), from 38.81 ± 1.68 to 324.7 ± 9.42. These values are lower than the limit of 370 Bq·kg-1 adopted by the Organization for Economic Cooperation and Development (OECD). The average indoor annual effective gamma dose rate (DE) in (mSv/y) for the people, caused by the building materials of dwellings, was assessed for most commonly gypsum materials. It was estimated to be in the range from 0.10 ± 0.003 mSv/y to 0.74 ± 0.08 mSv/y. The internal and external hazard indices (Hin, Hex) and the absorbed dose rate in air D in each sample were evaluated to assess the radiation hazard for people living in dwelling made of the studied materials. The absorbed dose rate of indoor air in samples G1, G2, G11, G17 and G18 is less than the international recommended value which is 55 nGyh-1. While the absorbed dose rate for samples G3, G4, G5, G6, G7, G8, G9, G10, G12

关键词： Gypsum Gamma Spectrometer Hazard Indices NORM Building Materials

Determination of Photon and Elementary Particles Rest Masses Using Maxwell’s Equations and Generalized Potential Dependent Special Relativity

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Natural Science 2020年第8期12卷 588-598页

作者： Abeer Mohammed Khairy Ahmed Mashair Ahmed Mohammed Yousif Zainab Mustapha Kurawa Zoalnoon Ahmed Abeid allah saad Suhair Salih Makawy Mohammed Idriss Mohammed Mubarak Dirar abd-Alla Sami abdalla Elbadawi Mohamed Departmentof Physics Faculty of Art and Science at AL Muznab AL Qassim University AL Muznab Kingdom of Saudi Arabia Department of Physics Faculty of Science and Education at Alkhurma Taif University Alkhurma Kingdom of Saudi Arabia Department of Physics School of Science Education Saadatu Rimi College of Education Kumbosto Kano Nigeria Departmentof Physics Faculty of Arts and Sciences Dhahran Aljanoub King Khalid University Dahran Kingdom of Saudi Arabia Department of Physics Faculty of Science Taif University Taif Kingdom of Saudi Arabia Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan Department of Physics Faculty of Education Gadarif University Gadarif Sudan

The nature and origin of the photon and elementary rest masses are some of the challeng-ing problems that physics face. The approaches used to solve these problems are complex and time-consuming. Specifically, the photon rest mass pays attention to theoretical physi-cists. Many experimental works show that the photon rest mass is non zero. This problem can be solved using generalized potential dependent special relativity, which has been de-rived using simple arguments, and Maxwell’s equations, besides the conventional Einstein energy-momentum relation. The results obtained show that the rest mass of photons and elementary particles are strongly dependent on the vacuum energy and a universal con-stant. This result conforms with the models that predict time decaying vacuum energy as-sociated with production of smaller rest mass particles followed by larger masses. The two potential dependent mass expressions conform with the cosmological models that suggest the photon is generated first by assuming the universe consisting of total constant vacuum with decaying cosmological part and mass generating part. Using Maxwell’s equations, beside plank and De Broglie hypothesis together with special relativity energy-momentum relation the photon rest mass is estimated. It was shown that the photon rest mass is ex-tremely small compared to the electron mass.

关键词： Photon Elementary Particles Maxwell’s Equations Potential Dependent Special Relativity Vacuum Energy