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Structural morphological and Optical Properties of SnSb_2S_4 Thin Films Grown by Vacuum Evaporation method

Journal of materials Science & Technology 2014年第10期30卷 1006-1011页

作者： N.Khedmi m.ben rabeh m.Kanzari Laboratoire de Photovoltaques et matriaux de Semi-conducteurs-ENIT-Universit de Tunis el manar BP 37le belvedere1002 TunisTunisie Laboratoire de Photovoltaques et matriaux de Semi-conducteurs-ENIT-IPEITunis montfleury-Universit de Tunis Tunisie

SnSb2S4 thin films were prepared from powder by thermal evaporation under vacuum of 1.33 × 10^-4 Pa （ 10^-6 Torr） on unheated glass substrates. The effect of thickness on the structural, morphological and optical properties of SnSb2S4 thin films was investigated. Films thickness measured by interference fringes method varied from 50 to 700 nm. X-ray diffraction analysis revealed that all the SnSb2S4 films were polycrystalline in spite without heating the substrates and the crystallinity was improved with increasing film thickness. The microstructure parameters： crystallite size, strain and dislocation density were calculated. It was observed that the crystallite size increased and the crystal defects decreased with increasing film thickness. In addition, by increasing the film thickness, an enhancement in the surface roughness root-mean-square （RmS） increased from 2.0 to 6.6 nm. The fundamental optical parameters like band gap, absorption and extinction coefficient were calculated in the strong absorption region of transmittance and reflectance spectrum. The optical absorption measurements indicated that the band （Eg） gap of the thin films decreased from 2.10 to 1.65 eV with increasing film thickness. The refractive indexes were evaluated in transparent region in terms of envelope method, which was suggested by Swanepoul. It was observed that the refractive index increased with increasing film thickness.

关键词： Ternary system Thermal evaporation technique Thin films Thickness Atomic force microscopy (AFm)

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Cooperative Target Fencing of multiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of Systems Science & Complexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN ben m Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem for n-dimensional systems and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull formed by the ***,the dynamics of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the communication network and collision avoidance among the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a numerical example.

关键词： multi-agent systems networked systems target fencing

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A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction

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Control Theory and Technology 2024年第3期22卷 394-405页

作者： Chuanxiang Gao Xinyi Wang Xi Chen ben m.Chen Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongShatinNTChina

Unmanned aerial vehicles(UAVs)are emerging as a powerful tool for inspections and repair works in large-scale and unstructured 3D infrastructures,but current approaches take a long time to cover the entire *** using UAVs for inspections and repair works puts forward a requirement of improving time efficiency in large-scale and cluster *** paper presents a hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction to balance the workload and reduce the overall task completion *** proposed framework consists of two stages,the exploration stage and the exploitation stage,resolving the task in a sequential *** the exploration stage,the density map is developed to update global and local information for dynamic load-balanced area partition based on reconstructability and relative positions of UAVs,and the Voronoi-based planner is used to enable the UAVs to reach their best *** obtaining the global map,viewpoints are generated and divided while taking into account the battery capacity of each ***,a shortest path planning method is used to minimize the total traveling cost of these viewpoints for obtaining a high-quality *** experiments are conducted in both a simulated and real environment to show the time efficiency,robustness,and effectiveness of the proposed ***,the whole system is implemented in real applications.

关键词： multi-UAV Coverage path planning Infrastructure inspection and reconstruction

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Intraocular pressure before and after capsulorhexis using two viscoelastic substances and two surgical approaches in enucleated porcine eyes

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1156-1160页

作者： Chiraz ben Abdallah Walter Sekundo markus SLadewig Daniel m.Handzel Augenzentrum Osthessen Fulda 36037Germany University Eye Hospital Philipps-University Marburg 35043Germany University Eye Hospital Philipps-University Campus FuldaFulda 36043Germany

AIm:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this ***:Prospective experimental WetLab study carried out on enucleated porcine *** was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss meditec AG,Germany;hydroxy propylmethylcellulosis(HPmC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the ***:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the *** use of different OVDs made no *** the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm *** difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD ***:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine *** use of different OVD has no significant influence on IOP drop.

关键词： cataract surgery ophthalmosurgical viscoelastic device intraocular pressure capsulorhexis enucleated porcine eye

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Natural Convection of a Power-Law Nanofluid in a Square Cavity with a Vertical Fin

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Fluid Dynamics & materials Processing 2024年第9期20卷 2091-2108页

作者： Amira m’hadbi mohammed El Ganaoui Haïkel ben Hamed Amenallah Guizani Khalid Chtaibi LERmAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

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Transverse momentum balance of dijets in Xe+Xe collisions at the LHC

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Nuclear Science and Techniques 2024年第7期35卷 137-146页

作者： Yao Li Shu-Wan Shen Sa Wang ben-Wei Zhang Key Laboratory of Quark&Lepton Physics(mOE)and Institute of Particle Physics Central China Normal UniversityWuhan430079China College of Science China Three Gorges UniversityYichang443002China Center for Astronomy and Space Sciences and Institute of modern Physics China Three Gorges UniversityYichang443002China Guangdong-Hong Kong Joint Laboratory of Quantum matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou510006China

We present a theoretical study of the medium modifications of the p_(T)balance (x_(J)) of dijets in Xe+Xe collisions at■.The initial production of dijets was carried out using the POWHEG+PYTHIA8 prescription,which matches the next-toleading-order (NLO) QCD matrix elements with the parton shower (PS) *** SHELL model described the in-medium evolution of nucleus–nucleus collisions using a transport *** theoretical results of the dijet xJin the Xe+Xe collisions exhibit more imbalanced distributions than those in the p+p collisions,consistent with recently reported ATLAS *** utilizing the Interleaved Flavor Neutralisation,an infrared-and-collinear-safe jet flavor algorithm,to identify the flavor of the reconstructed jets,we classify dijets processes into three categories:gluon–gluon (gg),quark–gluon (qg),and quark–quark (qq),and investigated the respective medium modification patterns and fraction changes of the gg,qg,and qq components of the dijet sample in Xe+Xe *** is shown that the increased fraction of qg component at a small x_(J)contributes to the imbalance of the dijet;in particular,the q_(1)g_(2)(quark-jet-leading) dijets experience more significant asymmetric energy loss than the g_(1)q_(2)(gluon-jet-leading) dijets traversing the *** comparing the■of inclusive,■ dijets in Xe+Xe collisions,we observe■.moreover,ρ_(Xe),P_(b),the ratios of the nuclear modification factors of dijets in Xe+Xe to those in Pb+Pb,were calculated,which indicates that the yield suppression of dijets in Pb+Pb is more pronounced than that in Xe+Xe owing to the larger radius of the lead nucleus.

关键词： Heavy-ion collisions Quark-gluon plasma Jet quenching Transverse momentum balance

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Substrate Temperature-Dependent Physical Properties of Thermally Evaporated Sn4Sb6S13 Thin Films

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Acta metallurgica Sinica(English Letters) 2016年第1期29卷 79-88页

作者： A. Harizi m. ben rabeh m. Kanzari Laboratoire de Photovoltaique et materiaux Semiconducteurs departement genie industriel ENIT-Universite Tunis E1 Manar BP 37 Le belvedere 1002 Tunis Tunisie Institut Preparatoire aux Etudes d'Ingenieurs de Tunis Universite de Tunisie Montfleury Tunisia

In this work, the homogenous thin films of sulfosalt Sn4Sb6S13 were successfully synthesized by the thermal evaporation technique onto coming 7059 glass substrates heated at various temperatures in the range of 30--200 ℃. The surface morphology and structural characteristics of Sn4Sb6S13 films were analyzed by atomic force microscopy, X-ray diffraction, and energy-dispersive X-ray, respectively. The X-ray diffraction analysis revealed that Sn4Sb6S13 thin films crystallized in monoclinic structure according to a preferential direction （6 11）. An improvement in the structural properties by increasing the substrate temperature was observed. The values of some important parameters such as absorption coefficient （x）, band gap （Eg）, refractive index （n）, extinction coefficient （k）, and dielectric constant （Eg） of thin film were determined. The absorption coefficient was larger than 105 cm-l in the visible range. The electron transition of Sn4Sb6S13 films was direct allowed with the values that decreased （2-1.69 eV） by increasing substrate temperature from 30 to 200 ℃,The dispersion data obeyed the single oscillator relation of the Wemple-DiDomenico model and Cauchy model. The electrical free carrier susceptibility and the carrier concentration of the effective mass ratio were estimated according to the model of Spitzer and Fan.

关键词： Thin film Thermal evaporation technique X-ray diffraction Optical parameters

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Practical fixed-time adaptive fuzzy control of uncertain nonlinear systems with time-varying asymmetric constraints: a unified barrier function based approach

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Frontiers of Information Technology & Electronic Engineering 2024年第9期25卷 1282-1294页

作者： Zixuan HUANG Huanqing WANG ben NIU Xudong ZHAO Adil m.AHmAD College of Engineering Bohai UniversityJinzhou 121013China College of mathematical Science Bohai UniversityJinzhou 121013China School of Information Science and Engineering Shandong Normal UniversityJinan 250014China Faculty of Electronic Information and Engineering Dalian University of TechnologyDalian 116024China Communication Systems and Networks Research Group Department of Information TechnologyFaculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddahSaudi Arabia

A practical fixed-time adaptive fuzzy control strategy is investigated for uncertain nonlinear systems with time-varying asymmetric constraints and input quantization. To overcome the difficulties of designing controllers under the state constraints, a unified barrier function approach is employed to construct a coordinate transformation that maps the original constrained system to an equivalent unconstrained one, thus relaxing the time-varying asymmetric constraints upon system states and avoiding the feasibility check condition typically required in the traditional barrier Lyapunov function based control approach. meanwhile, the “explosion of complexity” problem in the traditional backstepping approach arising from repeatedly derivatives of virtual controllers is solved by using the command filter method. It is verified via the fixed-time Lyapunov stability criterion that the system output can track a desired signal within a small error range in a predetermined time, and that all system states remain in the constraint range. Finally, two simulation examples are offered to demonstrate the effectiveness of the proposed strategy.

关键词： Unified barrier function Time-varying asymmetric state constraints Fuzzy logic systems Fixed-time control Command filter

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Experimental design of paraffin/methylated melamine-formaldehyde microencapsulated composite phase change material and the application in battery thermal management system

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Journal of materials Science & Technology 2024年第2期169卷 124-136页

作者： Que Huang Silong Wang Jichun He Dengji Xu Safaa NAbdou mohamed mIbrahim Shiqi Sun Yanjun Chen Handong Li ben Bin Xu Changcheng Liu Zeinhom m.El-Bahy Zhanhu Guo School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Institute of Advanced Energy materials and Systems North University of ChinaTaiyuan 030051China School of Resources and Safety Engineering Central South UniversityChangsha 410010China School of medical and BioInformation Engineering Northeastern UniversityShenyang 110819China Department of Chemistry Khurmah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

In order to maintain the optimal operating temperature of the battery surface and meet the demand for thermal storage technology,battery thermal management system based on phase change materials has attracted increasing *** this work,a kind of core-shell structured microcapsule was synthesized by an in-situ polymerization,where paraffin was used as the core,while methanol was applied to mod-ify the melamine-formaldehyde shell to reduce toxicity and improve thermal ***,three different types of heat conductive fillers with the same content of 10 wt.%,i.e.,nano-Al_(2)O_(3),nano-ZnO and carbon nanotubes were added,generating *** microcapsules were uniform,and were not affected by the thermal fillers,which were evenly dispersed *** composite sample with carbon nanotubes(10 wt.%)showed the highest thermal conductivity of 0.50 W/(m K)and latent heat of 139.64 J/***,according to the leakage testing and battery charge/discharge experiments,compared with Al_(2)O_(3)and ZnO,the addition of carbon nanotubes remarkably enhances the heat storage ability as latent heat from 126.98 J/g for the prepared sample with Al_(2)O_(3)and 125.86 J/g for the one with ZnO,then to 139.64 J/g,as well as dissipation performance as a cooling effect by decreasing the sur-face temperature of battery from 2%to 12%of microcapsule,composite sample with carbon nanotubes presents a broad application prospect in battery thermal management system and energy storage field.

关键词： microcapsule Phase change material Battery Carbon nanotube Safety

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Delayed Fluorescence and Amplified Chirality via modified Substitution Position for Deep-red Circularly Polarized Organic Light Emitting-diodes

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Chemical Research in Chinese Universities 2024年第4期40卷 657-663页

作者： ZHU Lixun LIU Dan WU Kaiwen XIE Guohua ZHAO Zheng TANG ben Zhong School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Shenzhen518172P.R.China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyHongkong999077P.R.China The Institute of Flexible Electronics(Future Technologies) Xiamen UniversityXiamen361005P.R.China

Developing easily accessible deep-red/near-infrared circularly polarized emitters for practical organic light-emitting diodes remains a significant ***,a practical strategy has been proposed for developing deep-red circularly polarized delayed fluorescent emitters based on a novel chiral acceptor *** changing triphenylamine(TPA)substitution position from para to meta,R/S-m-TBBTCN demonstrated thermally activated delayed fluorescence(TADF)properties with a delayed lifetime of 6.6µs that R/S-P-TBBTCN doesn’t ***,R/S-m-TBBTCN showed a 65 nm red-shift in emission and a 10-fold enhancement in asymmetry factor(glum),compared with R/*** solution-processed nondoped circularly polarized organic light-emitting diodes(CP-OLEDs)based on R-m-TBBTCN display deep-red emission and 2.2%external quantum efficiency.

关键词： Amplified chirality Deep-red circularly polarized organic light emitting-diode Binaphthol based chiral acceptor

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