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Two-Point Resistance on the Centered-Triangular Lattice

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Chinese Physics Letters 2018年第2期35卷 6-10页

作者： M.Q.Owaidat A.A.al-Badawi j.H.Asad Mohammed al-Twiessi Department of Physics Al-Hussein Bin Talal University Department of Physics Faculty of SciencesTaibah University Department of Physics Faculty of Arts and SciencesPalestine Technical University

The resistance between any two lattice points in an infinite, centered-triangular lattice of equal resistors is determined using the lattice green function method. It is shown that the two-point resistance on the centered-triangular lattice is expressed in terms of the resistance of a triangular lattice. Some exact values for the resistance near the origin of the lattice are presented. for large separation between lattice points the asymptotic forms of the resistance are calculated.

关键词： Two-Point Resistance on the Centered-Triangular Lattice

Annealing Effects on the Structural, Optical, and UV Photoresponse Properties of ZnO Nanostructures Prepared by Rf-Magnetron Sputtering at Different Deposition Temperatures

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 230-242页

作者： Husam S.al-Salman M.j.Abdullah School of Physics University Sains Malaysia Department of Physics College of Science University of Basrah

Undoped ZnO nanostructures were deposited on SiO2/Si substrates via radio 11：equency magnetron sputtenng at different deposition temperatures （room temperature, 200, 300, and 400 ℃）. The prepared samples were annealed at 500 ℃ for 2 h under an N2 flow. The structural, surface morphological, optical, and photoresponse characteristics of ZnO nanostructures as deposited and after annealing were then investigated. The energy bandgaps of all samples after annealing （3.22-3.28 eV） decreased compared with those of the as-deposited specimens. The barrier height increased when the deposition temperature increased and reached 0.77 eV at 400 ℃ after annealing with a leakage current of 0.17 gA at a 5 V bias. The UV photodetector device which was deposited at the optimal temperature of 300 ℃, has 12.51 × 10^3% pho- tosensitivity, 2.259 pA dark current, 0.508 s response time, and 0.466 s recovery time. The dark current significantly decreased for all samples after annealing. The proposed UV photodetectors exhibit high performance, high photosensi- tivity, shorter response and recovery times, and excellent stability at lower bias voltages of 5 and 2 V.

关键词： Undoped ZnO UV photoresponse Deposition temperatures Annealing effect

Synergistic optimization framework for the process synthesis and design of biorefineries

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frontiers of Chemical Science and Engineering 2022年第2期16卷 251-273页

作者： Nikolaus IVollmer Resul al Krist V.gernaey gürkan Sin Process and Systems Engineering(PROSYS)Research Center Department of Chemical and Biochemical EngineeringTechnical University of Denmark2800 Kgs.LyngbyDenmark Novo Nordisk A/S 2880 BagsværdDenmark

The conceptual process design of novel bioprocesses in biorefinery setups is an important task,which remains yet challenging due to several *** propose a novel framework incorporating superstructure optimization and simulation-based optimization *** this context,several approaches for superstructure optimization based on different surrogate models can be *** means of a case study,the framework is introduced and validated,and the different superstructure optimization approaches are *** results indicate that even though surrogate-based optimization approaches alleviate the underlying computational issues,there remains a potential issue regarding their *** development of appropriate surrogate models,comprising the selection of surrogate type,sampling type,and size for training and cross-validation sets,are essential *** this aspect,satisfactory validation metrics do not ensure a successful outcome from its embedded use in an optimization ***,the framework’s synergistic effects by sequentially performing superstructure optimization to determine candidate process topologies and simulationbased optimization to consolidate the process design under uncertainty offer an alternative and promising *** findings invite for a critical assessment of surrogatebased optimization approaches and point out the necessity of benchmarking to ensure consistency and quality of optimized solutions.

关键词： biotechnology surrogate modelling superstructure optimization simulation-based optimization process design

fabrication and Characterization of Undoped and Cobalt-doped ZnO Based UV Photodetector Prepared by Rf-sputtering

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journal of Materials Science & Technology 2013年第12期29卷 1139-1145页

作者： Husam S.al-Salman M.j.Abdullah School of Physics University Sains Malaysia Department of Physics College of ScienceUniversity of Basrah

Undoped and 1 at.% Co-doped ZnO nanostructure based UV photodetectors were successfully fabricated by Rf- magnetron sputtering technique with comb like Pt electrodes. Cobalt ions were successfully incorporated into the lattice of the ZnO nanostructure without changing its wurtzite structure. It was indicated that Co-doping can effectively adjust the luminescence properties of the ZnO nanostructure. The undoped and Co-doped ZnO photodetectors were observed to have photosensitivities of 1.44 x 104 % and 8.57 x 102 % and low dark currents of 9.74 x 10-8 A and 1.18 x 10-7 A, respectively.

关键词： Characterization Co-doped ZnO UV photodetector

Numerical simulation and analysis of confined turbulent buoyant jet with variable source

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journal of Hydrodynamics 2015年第6期27卷 955-968页

作者： EL-AMIN Mohamed f. al-gHAMDI Abdulmajeed SalAMA Amgad SUN Shuyu Mathematics Department Faculty of ScienceAswan University Computational Transport Phenomena Laboratory(CTPL) Division of Physical Sciences and Engineering(PSE)King Abdullah University of Science and Technology(KAUST) College of Engineering and Islamic Architecture Umm Al-Qura University

In this work, experimental and numerical investigations are undertaken for confined buoyant turbulent jet with varying inlet temperatures. Results of the experimental work and numerical simulations for the problem under consideration are presented. four cases of different variable inlet temperatures and different flow rates are considered. The realizable k-ε turbulence model is used to model the turbulent flow. Comparisons show good agreements between simulated and measured results. The average devia- tion of the simulated temperature by realizable k-ε turbulent model and the measured temperature is within 2%. The results indicate that temperatures along the vertical axis vary, generally, in nonlinear fashion as opposed to the approximately linear varia- tion that was observed for the constant inlet temperature that was done in a previous work. furthermore, thermal stratification exits, particularly closer to the entrance region. further away from the entrance region the variation in temperatures becomes relatively smaller. The stratification is observed since the start of the experiment and continues during the whole course. Numerical experime- nts for constant, monotone increasing and monotone decreasing of inlet temperature are done to show its effect on the buoyancy force in terms of Richardson number.

关键词： realizable k-ε model turbulent jet stratification heat stores CfD

green Approach to Corrosion Inhibition of Mild Steel by Lignin Sulfonate in Acidic Media

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journal of Iron and Steel Research International 2016年第7期23卷 722-732页

作者： Muna A.ABU-DalO Nathir A.f.al-RAWASHDEH Ahmed A.MUTLAQ Department of Applied Chemical Sciences Jordan University of Science and Technology

The inhibition effect of lignin sulfonate against corrosion for mild steel in acidic solution has been examined by means of fTIR（fourier transform infrared spectroscopy）,fAA（flame atomic absorption）spectroscopy,SEM（scanning electron microscope）,EDS（energy dispersive X-ray spectroscopy）,and mass loss *** results revealed that lignin is a beneficial inhibitor for mild steel corrosion in acidic *** has been further found that Langmuir adsorption isotherm is obeyed by the tested lignin′s adsorption over the surface of mild *** range of inhibition efficiency（IE）in 2mol·L^（-1） HCl was found to be 75.88%-87.88%for Reax 88 A,40.72%-60.32%for Reax 88 B,and 54.32%-63.03%for Reax 100 M,after immersed at 298 Kfor 24htime.

关键词： mild steel fourier transform infrared spectroscopy inhibition adsorption corrosion

IoMT-Based Healthcare framework for Ambient Assisted Living Using a Convolutional Neural Network

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Computers, Materials & Continua 2023年第3期74卷 6867-6878页

作者： Waleed T.al-Sit Nidal A.al-Dmour Taher M.ghazal ghassan f.Issa Department of Computer Engineering Mutah UniversityAl-KarakJordanHigher Colleges of TechnologyDubaiUAE Department of Computer Engineering College of EngineeringMutah UniversityJordan School of Information Technology Skyline University CollegeUniversity City SharjahSharjahUAE Center for Cyber Security Faculty of Information Science and TechnologyUKM43600BangiSelangorMalaysia

In the age of universal computing,human life is becoming smarter owing to the recent developments in the Internet of Medical Things(IoMT),wearable sensors,and telecommunication innovations,which provide more effective and smarter healthcare *** has the potential to shape the future of clinical research in the healthcare *** sensors,patients,healthcare providers,and caregivers can connect through an IoMT network using software,information,and communication *** assisted living(Aal)allows the incorporation of emerging innovations into the routine life events of *** learning(ML)teaches machines to learn from human experiences and to use computer algorithms to“learn”information directly instead of relying on a *** the sample size accessible for learning increases,the performance of the algorithms *** paper proposes a novel IoMT-enabled smart healthcare framework for Aal to monitor the physical actions of patients using a convolutional neural network(CNN)algorithm for fast analysis,improved decision-making,and enhanced treatment *** simulation results showed that the prediction accuracy of the proposed framework is higher than those of previously published approaches.

关键词： Smart healthcare system neural network machine learning

fast laser surface texturing of spherical samples to improve the frictional performance of elasto-hydrodynamic lubricated contacts

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friction 2021年第5期9卷 1227-1241页

作者： g.BOIDI P.g.gRÜTZMACHER A.KADIRIC f.j.PROfITO I.f.MACHADO C.gACHOT D.DINI Department of Mechanical Engineering Imperial College LondonSouth Kensington CampusLondon SW72AZUK AC2T research gmbH Wiener Neustadt 2700Austria Polytechnic School University of São Paulo–USPSão Paulo 05508-030Brazil Department of Engineering Design and Product Development TU WienWien 1060Austria Department of Material Science and Engineering Saarland UniversitySaarbrücken 66123Germany

Textured surfaces offer the potential to promote friction and wear reduction by increasing the hydrodynamic pressure,fluid uptake,or acting as oil or debris ***,texturing techniques often require additional manufacturing steps and costs,thus frequently being not economically feasible for real engineering *** experimental study aims at applying a fast laser texturing technique on curved surfaces for obtaining superior tribological performances.A femtosecond pulsed laser(Ti:Sapphire)and direct laser interference patterning(with a solid‐state Nd:YAg laser)were used for manufacturing dimple and groove patterns on curved steel surfaces(ball samples).Tribological tests were carried out under elasto‐hydrodynamic lubricated contact conditions varying slide‐roll ratio using a ball‐on‐disk ***,a specific interferometry technique for rough surfaces was used to measure the film thickness of smooth and textured *** steel samples were used to obtain data for the reference *** results showed that dimples promoted friction reduction(up to 20%)compared to the reference smooth specimens,whereas grooves generally caused less beneficial or detrimental *** addition,dimples promoted the formation of full film lubrication conditions at lower *** study demonstrates how fast texturing techniques could potentially be used for improving the tribological performance of bearings as well as other mechanical components utilised in several engineering applications.

关键词： surface laser texturing elasto‐hydrodynamic lubrication bearings friction film thickness

Xiamen after 20 Years of Ecological Transformation

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China Today 2025年第1期74卷 66-68页

作者： ZACHARY g.LUNDQUIST 不详

The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean *** years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s fujian ***,due to the fact that I was in a rush,I did not have the chance to see the whole *** memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this *** years went by until I was able to return to this city *** emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and *** exactly had given this city such vitality?

关键词： Ecological Xiamen Transformation