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Progress in Natural science:Materials International 2018年第4期28卷 478-482页

作者： Imran sadiq shahzad Naseem saira Riaz s.sajjad hussain Muhammad Naeem Ashiq Mazhar Rana Centre of Excellence in solid state Physics University of the Punjab Institute of Chemical sciences Bahauddin Zakariya University

Rare earth Dy;and divalent Mn;elements substituting W-type hexagonal ferrites Ba;Dy;Zn;Fe;Mn;O;（x=0,0.02,0.06,0.1 and y=0,0.1,0.3,0.5）were prepared by sol-gel *** thermo-gravimetric analysis（TGA）and differential scanning calorimetry（DsC）was carried out to find the temperature at which single phase can be *** patterns indicate the presence of the single phase for all the synthesized samples with the absence of any extra peak due to unreacted material and secondary *** occurrence of absorption bands at low wave numbers(563 and 446 cm;),can be assigned to the stretching vibration of metal and oxygen ions in FTIR spectra,which also confirms the single hexagonal phase for prepared *** grains are of platelet like structure,which enhances the microwave absorption properties of hexagonal *** synthesized material exhibits the minimum reflection loss of-20.9 dB at 11.8 GHz frequency,which reflects the applications of this material in super high frequency *** microwave conductivity of the material increases with frequency.

关键词： sol-Gel synthesis XRD Microwave absorption properties Microwave conductivity

Electron Heat Diffusivity Measurement by Perturbative Method on HT-7 Tokamak

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Plasma science and Technology 2008年第6期10卷 681-684页

作者：杜勤凌必利提昂高翔费勤山 s.sajjad 熊川 Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China

spatio-temporal evolutions of the sawteeth activities are measured simultaneously with a 16 channel high spatio-temporal resolution electron cyclotron emission （ECE） heterodyne radiometer on HT-7 and the evolutions of the sawteeth are found to be diffusive in character. By a perturbative analysis, the electron heat diffusivity Хe inferred by time-to-peak method and Fourier transform shows a good agreement. The value of electron heat diffusivity shows radial asymmetry between the low magnetic field side （LFs） and the high magnetic field side （HFs）. It is observed that with the increase in plasma density, the electron heat diffusivity decreases and the confinement of energy is improved. By comparing with Хe^pb inferred by static power balance analysis, the result indicate that Хe^hp is larger than Хe^pb by a factor ranging from 2 to 10.

关键词： ECE electron thermal diffusivity time-to-peak Fourier transform

Effect of number density on velocity distributions in a driven quasi-two-dimensional granular gas

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Chinese Physics B 2010年第10期19卷 617-622页

作者： sajjad hussain shah 李寅阊厚美瑛 Institute of Physics Chinese Academy of Sciences Physics Department Beijing Institute of Technology

The motion of mono-disperse spherical steel particles in a vibration driven quasi-two-dimensional （2D） square cell is studied. The cell is horizontally vibrated to eliminate the effect of gravity compaction. The velocity distributions at different particle number densities are studied and found to obey the form exp[-β（｜Vy｜/σy）α], in which Vy and （σy are velocity and its variance in the transverse direction, and α and β are fitting parameters. The value of α is found to decrease with the number density of particles increasing. To investigate the effect of the bottom plate, the molecular dynamics simulation without considering any bottom friction is performed. The accordance between the simulation result and the experimental result shows that the influence of bottom plate friction force on the high energy tail of the velocity distribution can be neglected.

关键词： granular matter velocity distribution

Runaway Electron Beam Instability in slide-Away Discharges in the HT-7 Tokamak

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Chinese Physics Letters 2007年第11期24卷 3195-3198页

作者：陈忠勇万宝年凌必利高翔杜勤提昂林士耀 s.sajjad HT-7 Team Department of Physics Yunnan Normal University Kunming 650092 Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 不详

slide-away discharges are achieved by decreasing the plasma density or ramping down the plasma current in runaway discharges in the HT-7 tokamak. In the case of plasma current ramp down, the ratio of the electron plasma frequency to the electron cyclotron frequency is higher than in the stationary pulses when the discharge goes into a slide-away regime. The instability regime is characterized by relaxations in the electron cyclotron emission due to relativistic anomalous Doppler effect which transfers energy from parallel to perpendicular motion. The triggering of relativistic anomalous Doppler effect at higher density by ramping down of plasma current may provide a alternative runaway energy control scenario.

关键词： coated conductor buffer layer self-epitaxy CeO2

Cooperative subcarrier sensing Using Antenna Diversity Based Weighted Virtual sub Clustering

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China Communications 2016年第10期13卷 44-57页

作者： Bushra Mughal sajjad hussain Abdul Ghafoor College of signals National University of Sciences and Technology (NUST) school of Engineering University of Glasgow

The idea of cooperation and the clustering amongst cognitive radios(CRs) has recently been focus of attention of research community, owing to its potential to improve performance of spectrum sensing(ss) schemes. This focus has led to the paradigm of cluster based cooperative spectrum sensing(CBCss). In perspective of high date rate 4th generation wireless systems, which are characterized by orthogonal frequency division multiplexing(OFDM) and spatial diversity, there is a need to devise effective ss strategies. A novel CBCss scheme is proposed for OFDM subcarrier detection in order to enable the non-contiguous OFDM(NC-OFDM) at the physical layer of CRs for efficient utilization of spectrum holes. Proposed scheme is based on the energy detection in MIMO CR network, using equal gain combiner as diversity combining technique, hard combining(AND, OR and Majority) rule as data fusion technique and antenna diversity based weighted clustering as virtual sub clustering algorithm. Results of proposed CBCss are compared with conventional CBCss scheme for AND, OR and Majority data fusion rules. Moreover the effects of antenna diversity, cooperation and cooperating clusters are also discussed.

关键词： cooperative spectrum sensing MIMO based clustering OFDM subcarrier detection energy detection

Invariant of Enhanced AEs Algorithm Implementations Against Power Analysis Attacks

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Computers, Materials & Continua 2022年第7期72卷 1861-1875页

作者： Nadia Mustaqim Ansari Rashid hussain sheeraz Arif syed sajjad hussain Department of Electronic Engineering Dawood University of Engineering&TechnologyKarachiPakistan Faculty of Engineering sciences and Technology Hamdard UniversityKarachiPakistan Faculty of Information Technology Salim Habib UniversityKarachiPakistan Faculty of Computer sciences SZABISTKarachiPakistan

The security of Internet of Things(IoT)is a challenging task for researchers due to plethora of IoT *** Channel Attacks(sCA)are one of the major *** prime objective of sCA is to acquire the information by observing the power consumption,electromagnetic(EM)field,timing analysis,and acoustics of the ***,the attackers perform statistical functions to recover the *** Encryption standard(AEs)algorithm has proved to be a good security solution for constrained IoT *** paper implements a simulation model which is used to modify theAEs algorithm using logicalmasking *** invariant of the AEs algorithm hides the array of bits during substitution byte transformation of *** model is used against sCAand particularly Power Analysis Attacks(PAAs).simulation model is designed on MATLAB *** will give better solution by hiding power profiles of the IoT devices against *** future,the lightweight AEs algorithm with false key mechanisms and power reduction techniques such as wave dynamic differential logic(WDDL)will be used to safeguard IoT devices against side channel attacks by using Arduino and field programmable gate array(FPGA).

关键词： side channel attacks power analysis attacks network security masking advance encryption standard

Thermo-bioconvection transport of nanofluid over an inclined stretching cylinder with Cattaneo–Christov double-diffusion

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Communications in Theoretical Physics 2021年第7期73卷 47-58页

作者： Hassan Waqas Umair Manzoor Taseer Muhammad sajjad hussain Department of Mathematics Government College University FaisalabadLayyah Campus 31200Pakistan Department of Mathematics College of SciencesKing Khalid UniversityAbha 61413Saudi Arabia Mathematical Modelling and Applied Computation Research Group(MMAC) Department of MathematicsKing Abdulaziz UniversityPO Box 80203Jeddah 21589Saudi Arabia

In this paper,Newtonian nanofluid flow is observed under the effects of the magnetic field,activation energy and motile microorganisms over an inclined stretchable *** magnificent aspects of nanoliquid are demonstrated by enduring the Brownian motion and thermophoresis diffusion *** higher order partial differential equations are transformed into first-order ordinary differential equations with suitable similarity *** attained sets of governing equations are then cracked by bvp4 c procedure in MATLAB mathematical *** numerical and graphical outcomes of controlling parameters such as Prandtl number,mixed convection,activation energy,thermophoresis,Brownian parameter,Biot number,Lewis number,Peclet number and motile concentration parameter against the velocity,temperature,volumetric concentration and motile concentration of nanoparticles of the fluid are *** velocity is enhanced with the growth valuation in mixed convection and decay by rising variation of buoyancy ratio parameter,magnetic parameter and bio-convective Rayleigh *** evolution in motile microorganisms is due to the increasing values of microorganisms Biot *** presented data can be helpful in enhancement of manufacturing processes,biomolecules,extrusion systems applications and energy production improvement.

关键词： bio-convection magnetic-nanofluid Cattaneo–Christov theory motile microorganisms inclined stretching cylinder

PdCu alloy anchored defective titania for photocatalytic conversion of carbon dioxide into methane with 100% selectivity

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Journal of Energy Chemistry 2024年第4期91卷 254-265页

作者： Lina Zhang sajjad hussain Qiuye Li Jianjun Yang National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina

The photoreduction of CO_(2)into CH_(4)with simultaneous high activity and selectivity is a promising strategy to increase energy supply and alleviate global ***,the absence of the active sites that is responsible for the adsorption and activation of CO_(2)and the generation of CO and H2via side reactions often lead to poor efficiency and low selectivity of the ***,Cu,Pd,and PdCu metal clusters cocatalyst-anchored defective TiO_(2)nanotubes(Cu/TiO_(2)-sBO,Pd/TiO_(2)-sBO,and Pd1Cu1/TiO_(2)-sBO)were designed via a simple solution impregnation reduction and applied for photocatalytic conversion of CO_(2)to CH_(4).The Pd1Cu1/TiO_(2)-sBO photocatalyst exhibits excellent catalytic performance among the other catalysts for photoreduction of CO_(2)into CH_(4).More interestingly,the product selectivity of CH_(4)reaches up to 100%with a rate of 25μmol g^(-1)h^(-1).In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTs)and density functional theory(DFT)simulations indicate that the main reasons for the high selectivity of CH_(4)are attributed to the PdCu alloy and oxygen vacancies,which jointly enhance the photoinduced carrier separation and lower energy barriers of key ***,due to the tunable d-band center of the Cu site in the PdCu alloy,the generated intermediates can be well prevented from poisoning and promoted to participate in further ***,the current study will provide insight into the development of new,highly selective photocatalysts for the visible light-catalytic reduction of CO_(2)into CH_(4).

关键词： PdCu alloy Defective TiO_(2) Photoreduction of CO_(2) Photocatalytic mechanism

CO oxidation on MXene(Mo_(2)Cs_(2)) supported single-atom catalyst: A termolecular Eley-Rideal mechanism

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Chinese Chemical Letters 2023年第2期34卷 519-528页

作者： shamraiz hussain Talib Zhansheng Lu Beenish Bashir sajjad hussain Khalil Ahmad salahuddin Khan sajjad Haider Zongxian Yang Kersti Hermansson Jun Li school of Physics Henan Normal UniversityXinxiang 453007China Department of Chemistry and Key Laboratory of Organic Optoelectronics&Molecular Engineering of Ministry of Education Tsinghua UniversityBeijing 100084China Department of Materials science and Engineering Southern University of Science and TechnologyShenzhen 518055China school of Chemistry Minhaj UniversityLahore 54000Pakistan Department of Chemistry Mirpur University of Science and Technology(MUST)MirpurAJK 10250Pakistan College of Engineering King Saud UniversityPO Box 800Riyadh 11421Saudi Arabia Chemical Engineering Department College of EngineeringKing Saud UniversityPO Box 800Riyadh 11421Saudi Arabia Department of Chemistry-Ångström Uppsala UniversityBox 538Uppsala 75121Sweden Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

Finding transition metal catalysts for effective catalytic conversion of CO to CO_(2)has attracted much *** as a new 2D layered material of early transition metal carbides,nitrides,and carbo-nitrides is a robust support for achoring metal *** this study,the electronic structure,geometries,thermodynamic stability,and catalytic activity of MXene (Mo_(2)Cs_(2)) supported single noble metal atoms (NM=Ru,Rh,Pd,Ir,Pt and Au) have been systematically examined using first-principles calculations and ab initio molecular dynamic (AIMD) ***,AIMD simulations and phonon spectra demonstrate the dynamic and thermal stabilities of Mo_(2)Cs_(2)*** likely reaction pathways,LangmuirHinshelwood (LH),Eley-Rideal (ER),and Termolecular Eley–Rideal (TER) for CO oxidation on the Ru1-and Ir_(1)@Mo_(2)Cs_(2)sACs,have been studied in *** is found that CO oxidation mainly proceeds via the TER mechanism under mild reaction *** corresponding rate-determining steps are the dissociation of the intermediate (OCO-Ru_(1)-OCO) and formation of OCO-Ir_(1)-OCO *** downshift d-band center of Ru1-and Ir_(1)@Mo_(2)Cs_(2)help to enhance activity and improve catalytst ***,a microkinetic study predicts a maximum CO oxidation rate of 4.01×10^(2)s^(-1)and 4.15×10^(3)s^(-1)(298.15K) following the TER pathway for the Ru_(1)-and Ir_(1)@Mo_(2)Cs_(2)catalysts,*** work provides guideline for fabricating and designing highly efficient sACs with superb catalyts using MXene materials.

关键词： CO oxidation Quantum chemical study 2D MXene monolayer M1@Mo_(2)Cs_(2) Termolecular Eley–Rideal single-atom catalysis

Thickness-dependent monochalcogenide Gese-based CBRAM for memory and artificial electronic synapses

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Nano Research 2022年第3期15卷 2263-2277页

作者： Asif Ali Haider Abbas Muhammad hussain syed Hassan Abbas Jaffery sajjad hussain Changhwan Choi Jongwan Jung HMC(Hybrid Materials Center)and Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 143–747Republic of Korea Division of Materials science and Engineering Hanyang UniversitySeoul 04763Republic of Korea

Investigating the promising chalcogenide materials for the development of memory and advanced neuromorphic computing applications is a critical step in realizing electronic memory and synaptic devices that can efficiently emulate biological synaptic ***,the assessment of monochalcogenide materials for the fabrication of highly scalable memory and electronic synaptic devices that can accurately mimic synaptic functions remain *** the present study,we investigated the thickness-dependent resistive switching(Rs)behavior of conductive bridge random access memory(CBRAM)based on a monochalcogenide Gese switching medium for its possible application in high-performance memory and electronic *** thin films of different thicknesses(6,13,24,35,47,and 56 nm)were deposited via sputtering to fabricate CBRAM devices with a stacking sequence of Ag/Gese/Pt/Ti/siO_(2).The devices exhibited compliance current(CC)-free and electroforming-free Rs with highly stable endurance and retention characteristics with no major *** devices with a thickness of 6 nm had a low-resistance state(LRs),which required an initial reset to ensure reliable switching *** devices with a thickness of 47 nm and above exhibited the co-existence of unipolar resistive switching(U-Rs)and bipolar resistive switching(B-Rs)with the CC-controlled transition between the two switching *** resistance states in the 24-nm device between a high-resistance state(HRs)and an LRs were achieved by controlling the set-CC(from 5 mA to CC-free)and the reset stop voltage(from–0.5 to–1.0 V)during the set and reset processes,*** analog Rs behavior of the device was further investigated with appropriate pulse measurements to emulate vital synaptic functions,including long-term potentiation(LTP),long-term depression(LTD),spike-rate-dependent plasticity(sRDP),spike-timing-dependent plasticity(sTDP),paired-pulse facilitation(PPF),paired-pulse depression(PPD)and

关键词： conductive bridge random access memory(CBRAM) resistive memory switching monochalcogenide material bipolar and unipolar resistive switching multilevel resistive switching electronic synapses