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Acid-treated carbon nanotubes and their effects on mortar strength

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Frontiers of Structural and Civil Engineering 2016年第2期10卷 180-188页

作者： M. ELKASHEF K. WAnG M.n. abou-ZEId Civil Construction and Environmental Engineering Department Iowa State University Ames IA 50011-2151 USA Construction and Architectural Engineering department The American University in Cairo Egypt

In the present study, multi-walled carbon nanotubes （MWCnTs） were treated in an acidic mixture solution, made with nitric and sulfuric acids in a ratio of 3：1 by volume. The durations of the treatment were 100 and 180 min. The defects of these treated MWCnTs were examined using Raman spectroscopy. The attachment of hydroxyl functional groups to the walls of the MWCnTs were verified using FTIR spectroscopy. The dispersion of CnTs with acid treatment is assessed using UV-Vis spectroscopy and Scanning Electron Microscopy （SEM）. The results indicate that the duration of the acid treatment has significant effect on both the degree of defects and functionality of the MWCnT. The compressive strength of mortar increased with the addition of the acid-treated MWCnTs; however, no appreciable difference was noted for the two treatment durations under this study.

关键词： carbon nanotubes concrete composites nanomaterials cement

Microstructure and Mechanical Properties of nano-crystalline Al-8 wt pct ni Alloy

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Journal of Materials Science & Technology 2006年第5期22卷 605-610页

作者： M.abou Zied Physics department Faculty of Science South Valley UniversityQena 83511Egypt

Microstructure and mechanical properties of ball-milled Al-8 wt pct ni ribbon have been investigated by X-ray diffraction （XRd） and continuous Vickers hardness test, respectively. The results indicate that, the main phases of this alloy are α-Al and orthorhombic-Al3ni. The lattice parameter of α-Al increases with increasing milling time. From the elastic constant of Al, the average contrast factors of the （111）, （200）, （220）, （311） and （222） Bragg＇s reflections for pure edge and pure screw dislocations in fcc crystals with α/2〈110〉{111} slip system were calculated. The average grain size and dislocation parameters as a function Of milling time have been investigated using the modified Williamson-hall plot and the Warren-Averbach equation, *** attempt has been made to correlate the micro-hardness of milled ribbon with their grain size through the hall-Patch relationship：HV0.01 = 742.45 〈 d 〉^-1/2 ＋401.55 （kg/mm^2）.

关键词： Aluminum Microstructure Property X-ray diffraction

Wafer-scale quasi-layered tungstate-doped polypyrrole film with high volumetric capacitance

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nano Research 2023年第4期16卷 4895-4900页

作者： Huabo Liu Jiaxing Liang John Watt Richard d.Tilley Rose amal da-Wei Wang School of Chemical Engineering University of New South WalesSydneyNSW 2052Australia 2 Center for Integrated NanotechnologiesLos Alamos National LaboratoryLos AlamosNW 87545USA 3 School of ChemistryUniversity of New South WalesSydneyNSW 2052Australia

Layered materials are particularly attractive for supercapacitors because of their unique physical,electrical and chemical ***,we demonstrate a facile and scalable electrochemical deposition method for wafer-scale synthesis of quasilayered tungstate-doped polypyrrole films(named TALPy)with controllable thickness and *** as-prepared TALPy film exhibits a high gravimetric density and excellent volumetric capacitance,exceeding many high-performing carbon-and polymerbased film *** on combined results of ex-situ X-ray diffraction(XRd),Raman and X-ray photoelectron spectroscopy(XPS),it is determined that TALPy stores charge through an ion intercalation process accompanied by change in oxidation states of polypyrrole backbone,which is referred as intercalation *** these results suggest the great promise of electrochemical deposition as a scalable and controllable bottom-up approach for synthesizing quasi-layered conductive organic-inorganic hybrid films for electrochemical energy storage applications with high volumetric performance.

关键词： electrochemical deposition conductive polymer polypyrrole organic-inorganic hybrid supercapacitor intercalation pseudocapacitance

Superconducting parameter determination for (Co0.5Zn0.5Fe2O4)x/Cu0.5Tl0.5-1223 composite

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Journal of Advanced Ceramics 2016年第3期5卷 210-218页

作者： M.ME.BARAKAT n.AL-SAYYEd R.AWAd A.I.abou-ALY Physics department Faculty of Science Alexandria University Alexandria Egypt Physics department Faculty of Science Beirut Arab University Beirut Lebanon

The addition of magnetic Co0.5Zn0.5Fe2O4 nanoparticles to the superconducting Cu0.5Tl0.5-1223 phase has been used to investigate the electrical resistivity behavior of the composite above the superconducting transition temperature T c. This was studied according to the opening of spin gap and fluctuation conductivity. The results indicated that the pseudogap temperature (T*) and superconducting fluctuation temperature (T scf) change by increasing the addition of Co0.5Zn0.5Fe2O4 nanoparticles. It was found that T* is related to hole carrier concentration P and it also depends on the antiferromagnetic fluctuation affected by magnetic nanoparticles. The excess-conductivity analysis showed four different fluctuation regions started from high temperature up to T c, and they were denoted by short wave (sw), two-dimensional (2d), three-dimensional (3d), and critical (cr) fluctuations. The crossover temperature between 3d and 2d (T 3d–2d) in the mean field region was decreased by increasing the addition of Co0.5Zn0.5Fe2O4 nanoparticles, in accordance with the decrease in T scf with x. The coherence length at 0 K along c-axis ξ c(0), effective layer thickness of the 2d system d, and inter-layer coupling strength J were estimated as a function of Co0.5Zn0.5Fe2O4 nanoparticle addition. Moreover, the thermodynamics, lower and upper critical magnetic fields, as well as critical current density have been calculated from the Ginzburg number n G. It was found that the low concentration of Co0.5Zn0.5Fe2O4 nanoparticles up to x = 0.08 wt% improves the superconducting parameters of Cu0.5Tl0.5-1223 phase. On the contrary, these parameters were deteriorated for (Co0.5Zn0.5Fe2O4) x /Cu0.5Tl0.5-1223 composite with x > 0.08 wt%.

关键词： Co0.5Zn0.5Fe2O4 nanoparticles Cu0.5Tl0.5-1223 phase pseudogap temperature fluctuation conductivity

Trinary flip-flops using Savart plate and spatial light modulator for optical computation in multivalued logic

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Optoelectronics Letters 2008年第6期4卷 443-446页

作者： amal K Ghosh Amitabha Basuray department of Applied Electronics & Instrumentation Engineering Netaji Subhas Engineering College department of Applied Optics & Photonics University of Calcutta

The memory devices in multi-valued logic are of most significance in modem research. This paper deals with the implementation of basic memory devices in multi-valued logic using Savart plate and spatial light modulator （SLM） based optoelectronic circuits. Photons are used here as the carder to speed up the operations. Optical tree architecture （OTA） has been also utilized in the optical interconnection network. We have exploited the advantages of Savart plates, SLMs and OTA and proposed the SLM based high speed JK, d-type and T-type flip-flops in a trinary system.

关键词：激光调制器激光计算机多值逻辑计算机技术

Open charm mesons and charmonia in magnetized strange hadronic matter

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Chinese Physics C 2022年第8期46卷 91-113页

作者： amal Jahan C.S. Amruta Mishra department of Physics Indian Institute of TechnologyNew Delhi-110016India

We investigate the in-medium masses of open charm mesons(d(d^(0),d^(+)),■(■^(0),d^(-)),d_(s)(d_(s)^(+),d_(s)^(-)))and charmonium states(J/ψ,ψ(3686),ψ(3770),χ_(c0),χ_(c2)) in strongly magnetized isospin asymmetric strange hadronic matter using a chiral effective *** the presence of a magnetic field,the number and scalar densities of charged baryons have contributions from Landau energy *** mass modifications of open charm mesons result from their interactions with nucleons,hyperons,and the scalar fields(the non-strange field σ,strange field C and isovector field δ) in the presence of a magnetic *** mass modifications of the charmonium states result from the modification of gluon condensates in a medium simulated by the variation in the dilaton field(χ) in the chiral effective *** effects of finite quark masses are also incorporated in the trace of the energy-momentum tensor in quantum chromodynamics to investigate the mass shifts of charmonium *** in-medium masses of open charm mesons and charmonia are observed to decrease with an increase in baryon *** charged d^(+),d^(-),Z_(s)^(+),and d_(s)^(-)mesons have additional positive mass shifts due to Landau quantization in the presence of a magnetic *** effects of the strangeness fraction are observed to be more dominant for ■ mesons compared with d *** mass shifts of charmonia are observed to be larger in hyperonic media compared with nuclear media when the effect of the finite quark mass term is *** medium mass modifications can have observable consequences on the production of the open charm mesons and charmonia in high-energy asymmetric heavy-ion collision experiments.

关键词： open charm mesons charmonium states strange hadronic matter magnetic field heavy-ion collision chiral effective model

Oxygen-deficient bismuth tungstate and bismuth oxide composite photoanode with improved photostability

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Science Bulletin 2018年第15期63卷 990-996页

作者： Hoi Ying Chung Weijian Chen Xiaoming Wen Judy n. hart hao Wu Yuekun Lai Rose amal Yun hau ng Particles and Catalysis Research Croup School of Chemical Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia School of Photovoltaic and Renewable Energy Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia Centre for Micro-Photonics Faculty of Science Engineering and Technology Swinburne University of Technology Melbourne VIC 2122 Australia School of Materials Science and Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia national Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 China

A homogeneous layer of Bi_2O_3-Bi_(14)WO_(24) composite(BWO/Bi_2O_3) thin film was fabricated using a combination of electrodeposition and thermal treatment. The evenly distributed Bi14 WO24 component within the Bi_2O_3 layer was found to be important in stabilising the photoelectrochemical performances of Bi_2O_3 photoanode by promoting the photoelectron transport. The unmodified Bi_2O_3 suffered from severe photocorrosion as proven by X-ray diffraction(XRd) and inductively coupled plasma(ICP) analyses while the composite thin film was active without noticeable activity decay for at least 3 h of illumination. This strategy might be applicable to other photocatalysts with stability issues.

关键词： Bismuth oxide Bismuth tungstate Photocorrosion

The effect of nanosized CoFe2O4 addition on the magnetic properties of GdBa2Cu3O7-δ using AC magnetic susceptibility measurements

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Journal of Advanced Ceramics 2016年第1期5卷 93-101页

作者： R.AWAd n.H.MOhaMMEd A.I.abou ALY S.ISBER H.A.MOTAWEH d.EL-SAId BAKEER M.ROUMI(E) Physics department Faculty of Science Alexandria University Alexandria EgyptPhysics Department Faculty of Science Beirut Arab University Lebanon Physics department Faculty of Science Alexandria University Alexandria Egypt Physics department American University of Beirut Beirut Lebanon Physics department Faculty of Science Damanhur University Damanhur Egypt Accelerator Laboratory Lebanese Atomic Energy Commission Beirut Lebanon

Superconductor samples of type (CoFe2O4)xGdBa2Cu3O7-δ (0≤x≤0.1) were synthesized by the conventional solid-state reaction technique, whereas nanosized CoFe2O4 was prepared by co-precipitation method with grain size of about 8.5 nm. The elemental content of the prepared samples was determined using particle induced X-ray emission (PIXE). The temperature dependence of real (χ') and imaginary (χʺ) components of AC magnetic susceptibility (ACMS) at different magnetic field amplitude (3–15 Oe) was investigated. The analysis of the temperature dependence of ACMS was performed using Bean critical state model. The values of the critical current density J c at T > T p (T p is the inter-granular loss peak temperature) were calculated as a function of magnetic field and nanosized CoFe2O4 content. It was found that the low nanosized CoFe2O4 addition content (x = 0.01) improves the critical current density J c of Gd-123 superconducting phase. The observed variation of J c with temperature indicated that the weak links are changed from superconductor–normal metal–superconductor (SnS) for free sample to superconductor–insulator–superconductor (SIS) type of junctions for samples added with nanosized CoFe2O4 of x > 0.01. We also discussed the experimental results in the framework of the critical state model to estimate the effective volume fraction of the grains f g using Cole–Cole plots.

关键词： Gd-123 phase nanosized CoFe2O4 AC magnetic susceptibility (ACMS) critical current density particle induced X-ray emission (PIXE)

A deep Real-Time Fire Prediction Parallel d-Cnn Model on UdOO BOLT V8

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Computers, Materials & Continua 2022年第12期73卷 6237-6252页

作者： amal H.Alharbi hanan A.Hosni Mahmoud department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

hazardous incidences have significant influences on human life,and fire is one of the foremost causes of such hazard in most *** prediction and classification model from a set of fire images can decrease the risk of losing human lives and *** promotion of fire emergency can be of great ***,construction of these prediction models is relevant and *** article proposes an operative fire prediction model that depends on a prediction unit embedded in the processor UdOO BOLT V8 hardware to predict fires in real time.A fire image database is improved to enhance the images quality prior to classify them as either fire or *** proposed deep learning-based Very deep Convolutional networks Visual Geometry Group(VGG-16)model(Parallel VGG-16)is an enhanced version of the VGG-16 model,by incorporating parallel convolution layers and a fusion module for better *** experimental results validate the performance of the Parallel VGG-16 which achieves an accuracy of 97%,compared to the compared state-of-the-art ***,we integrate the prediction module into a UdOO BOLT V8 computer,which precisely controlled the fire alarm so that it can cautious people from fire in real *** this paper we propose a complete fire prediction model using a camera and the UdOO BOLT V8 embedded *** experiments validate the effectiveness and applicability of the proposed fire model.

关键词： Fire prediction UdOO BOLT V8 deep learning