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Journal of Energy Chemistry 2019年第12期28卷 68-76页

作者： Israf Ud Din Maizatul S.Shaharun a.naeem S Tasleem Pervaiz Ahmad Department of Chemistry College of Science and HumaniriesPrince Sarttam bin Abdulaziz UniversityAl-kharjSaudi Arabia Department of Fundamental and Applied Sciences Universiti Teknologi PETRONASMalaysia National Centre of Excellence in Physical Chemistry University of PeshawarPakistan Chemistry Department Kohat University of Science and TechnologyKohatPakistan Department of Physics University of Azad Jammu&Kashmir13100 MuzaffarabadPakistan

A series of novel carbon nanofibers(CNFs)based Cu-ZrO2 catalysts were synthesized by deposition precipitation *** investigate the influence of promoter,catalysts were loaded with 1,2,3 and 4 wt%ZnO and characterized by ICP-OES,HRTEM,BET,N2O chemisorption,TPR,XPS and CO2-TPD *** results revealed that physicochemical properties of the catalysts were strongly influenced by incorporation of ZnO to the parent *** surface area(SCu)and dispersion(DCu)were slightly decreased by incorporation of ZnO ***,SCuand DCuwere remarkably decreased when ZnO content was exceeded beyond 3 wt%.The catalytic performance was evaluated by using autoclave slurry reactor at a pressure and temperature of 30 bar and 180℃,*** promotion of CuZrO2/CNFs catalyst with 3 wt%of ZnO enhanced methanol synthesis rate from 32 to 45 g kg^-1 h^-***,with the ZnO promotion the selectivity to methanol was enhanced to 92%compared to 78%of the un-promoted Cu-ZrO2/CNFs catalyst at the expense of a lowered CO2 *** addition,the catalytic activity of this novel catalyst system for CO2 hydrogenation to methanol was compared with the recent literature data.

关键词： Methanol synthesis Slurry reactor Promoter effect Chemisorption studies CNFs CO2 conversion

Opto-Video Encryption Based on Logistic Adjusted Sine map in FrFT

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Computers, Materials & Continua 2022年第8期72卷 3651-3663页

作者： Osama S.Faragallah Ashraf Afifi Ibrahim F.Elashry Ensherah a.naeem Heba M.El-Hoseny Ahmed I.Sallam Hala S.El-sayed Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Electrical Engineering Kafrelsheikh UniversityKafrelsheikh 61519Egypt Electrical Department Faculty of Industrial EducationSuez UniversitySuez 43527Egypt Department of Electronics and Electrical Communication Engineering Al-Obour High Institute for Engineering and Technology 3036Egypt Department of Computer Science and Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt

In the last few years,videos became the most common form of information transmitted over the internet,and a lot of the traffic is confidential and must be protected and delivered safely to its intended *** introduces the challenges of presenting encryption systems that can encode videos securely and efficiently at the same *** paper presents an efficient opto-video encryption system using Logistic Adjusted Sine map(LASM)in the Fractional Fourier Transform(FrFT).In the presented opto-video LASM-based FrFT scheme,the encoded video is split into distinct frames and transformed into optical signals utilizing an optical *** of the developed optical video frames is ciphered by utilizing the LASM in optical FrFT system using two-phase modulation forms on the video frame,the first in the time-domain and the second in the FrFT *** the end,the ciphervideo frame is spotted utilizing a CCD digital camera and transformed into a digital structure that can be managed using a *** test the proposed opto-video LASM-based FrFT scheme using various security *** outcomes demonstrate that the presented scheme can effectively encrypt and decrypt video *** addition,it encrypts videos with a high level of encryption qualitywithout sacrificing its resistance to noise ***,the test outcomes demonstrate that the presented scheme is immune to known attacks.

关键词： Optical encryption FrFT logistic-adjusted sine map

Role of La_2_O3 as Promoter and Support in Ni/γ-Al_2O_3 Catalysts for Dry Reforming of Methane

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Chinese Journal of Chemical Engineering 2014年第1期22卷 28-37页

作者： Ahmed S.Al-Fatesh Muhammad a.naeem Anis H.Fakeeha Ahmed E.Abasaeed Chemical Engineering Department College of Engineering King Saud University

The nature of support and type of active metal affect catalytic performance. In this work, the effect of using La203 as promoter and support for Ni/γ-A1203 catalysts in dry reforming of methane was investigated. The reforming reactions were carried out at atmosphenc pressure in the temperature range of 500-2700℃. The activity and stability of the catalyst, carbon formation, and syngas （H2/CO） ratio were determined. Various techniques were applied for characterization of both fresh and used catalysts. Addition of La2O3 to the catalyst matrix improved the dispersion of Ni and adsorption of CO2, thus its activity and stability enhanced.

关键词： CO2 methane reforming.Ni/γ-A12O3 La2O3 carbon deposition H2/CO

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad naeem Ul Hassan Suliman Khan Mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Correction:Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space

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Computers, Materials & Continua 2025年第1期82卷 1461-1461页

作者： Mudassir Khalil Muhammad Imran Sharif Ahmed naeem Muhammad Umar Chaudhry Hafiz Tayyab Rauf Adham E.Ragab Department of Computer Engineering Bahauddin Zakariya UniversityMultan60000Pakistan Department of Computer Science Kansas State UniversityManhattanKS 66506USA Department of Computer Science University of Management and TechnologyLahore54000Pakistan Independent Researcher BradfordBD80HSUK Industrial Engineering Department Collage of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia

In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham *** Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–***:10.32604/cmc.2023.043687,URL:https://***/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab *** of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.

关键词： Deep Code CIELAB

Parameters effect on heterogeneous photocatalysed degradation of phenolin aqueous dispersion of TiO_2

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Journal of Environmental Sciences 2009年第4期21卷 527-533页

作者： KASHIF naeem Department of Urban and Civil Engineering Harbin Institute of Technology Shenzhen Graduate School

Photocatalytic degradation of phenol selected as model compound of organic pollutant had been investigated in aqueous titanium dioxide （TiO2） dispersion under UV irradiation. The effects of various parameters such as pH, catalyst concentration, phenol concentration, anions, metal ions, electron acceptors, and surfactants on the photocatalytic degradation of phenol were investigated. The degradation kinetics was determined by the change in phenol concentration employing UV-Vis spectrometry as a function of irradiation time. The degradation kinetics of phenol follows pseudo first-order kinetics. The results showed a significant dependence of the photocatalytic degradation of phenol on the functional parameters. The probable promising roles of the additives on the degradation process were discussed.

关键词： irradiation phenol photocatalytic degradation titanium dioxide UV light

Numerical and experimental study of wave shaper effects on detonation wave front

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Defence Technology（防务技术） 2018年第1期14卷 45-50页

作者： Khalid naeem Arshad Hussain SCME (NUST) Islamabad Simulation Lab.Room 113 SCME NUST H-12 Campus SCME (NUST) H-12 Campus

In the current study, streak camera was used to find concentricity of the assembly during detonation,investigate and compare shock front within the high explosive and behavior of the shock front on the surface of the liner, one containing wave shaper and the other without wave shaper. Streaks revealed that the whole assembly was concentric till the formation of the jet. Observed streaks vindicate the uniform propagation of shock front in both the cases. Results obtained for shock front velocities are in agreement with those obtained from simulations. In the presence of wave shaper higher shock front velocity was observed both in simulation and experiment. Simulation without wave-shaper showed that shock front struck the copper cone at grazing angle while in the presence of wave-shaper it struck at an angle of 125.

关键词： Shock front Streak camera Simulation Wave shaper

Distribution and leaching characteristics of trace elements in ashes as a function of different waste fuels and incineration technologies

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Journal of Environmental Sciences 2015年第10期27卷 9-21页

作者： naeem Saqib Mattias Backstrom Department of Science and Technology Man-Technology-Environment Research Centreorebro University

Impact of waste fuels（virgin/waste wood, mixed biofuel（peat, bark, wood chips） industrial,household, mixed waste fuel） and incineration technologies on partitioning and leaching behavior of trace elements has been investigated. Study included 4 grate fired and 9 fluidized boilers. Results showed that mixed waste incineration mostly caused increased transfer of trace elements to fly ash; particularly Pb/Zn. Waste wood incineration showed higher transfer of Cr,As and Zn to fly ash as compared to virgin wood. The possible reasons could be high input of trace element in waste fuel/change in volatilization behavior due to addition of certain waste fractions. The concentration of Cd and Zn increased in fly ash with incineration *** concentration in ashes decreased in order of Zn 〉 Cu 〉 Pb 〉 Cr 〉 Sb 〉 As 〉 Mo. The concentration levels of trace elements were mostly higher in fluidized boilers fly ashes as compared to grate boilers（especially for biofuel incineration）. It might be attributed to high combustion efficiency due to pre-treatment of waste in fluidized boilers. Leaching results indicated that water soluble forms of elements in ashes were low with few *** levels in ash and ash matrix properties（association of elements on ash particles）are crucial parameters affecting leaching. Leached amounts of Pb, Zn and Cr in 〉50% of fly ashes exceeded regulatory limit for disposal. 87% of chlorine in fly ashes washed out with water at the liquid to solid ratio 10 indicating excessive presence of alkali metal chlorides/alkaline earths.

关键词： Incineration residues Leaching behavior Biofuel incineration Metal distribution Waste incineration

Influence of supports on photocatalytic degradation of phenol and 4-chlorophenol in aqueous suspensions of titanium dioxide

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Journal of Environmental Sciences 2013年第2期25卷 399-404页

作者： Kashif naeem Feng Ouyang Central Analytical Facility Division Pakistan Institute of Nuclear Science and Technology Environmental Science and Engineering Research Center Harbin Institute of Technology Shenzhen Graduate School

The photocatalytic degradation of phenol and 4-chlorophenol （4-CP） in aqueous suspensions with the use of titanium dioxide （TiO2 ） under UV irradiation was examined. The effects of different supporting materials mixed physically with TiO2 were studied to achieve maximum degradation efficiency. Among the three supports, namely activated carbon （AC）, silica （SiO2 ） and zeolite （ZSM-5）, all exhibited paramount efficiency for degradation of phenol and 4-CP and was better than TiO2 alone. The optimum concentration was found to be 50 mg for all supporting materials. The efficiency order of the three supports was as follows： AC 〉 ZSM-5 〉 SiO2 , respectively. Whilst, the degradation of phenol and 4-CP was improved from 70.6% to 87.6% and 80.6% to 89.7%, respectively, within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also comparatively enhanced in the presence of cheaper rice husk and the activity was closed to ZSM-5 and lower than AC.

关键词： 4-chlorophenol phenol photocatalytic degradation support TiO2

Thin Film Flow of a Second Grade Fluid over a Stretching/Shrinking Sheet with Variable Temperature-Dependent Viscosity

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Chinese Physics Letters 2010年第3期27卷 212-215页

作者： S. Nadeem naeem Faraz Department of Mathematics Quaid-i-Azam University 45320 Islamabad Pakistan

Effects of variable viscosity on the flow and heat transfer in a thin film on a horizontal porous stretching sheet are analyzed. The steady boundary layer equations for momentum and thermal energy are simplified by using similarity transformations. The resulted and coupled nonlinear differential equations are solved by Homotopy analysis method. The results are presented graphically to interpret various physical parameters appearing in the problem.

关键词： Soft matter liquids and polymers Fluid dynamics Mathematical physics