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influence of alkaline treatment and fiber loading on the physical and mechanical properties of kenaf/polypropylene composites for variety of applications

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Progress in natural Science:materials international 2016年第6期26卷 657-664页

作者： majid niaz Akhtar Abu Bakar Sulong m.K.Fadzly Radzi n.F.ismail m.R.Raza norhamidi muhamad muhammad Azhar khan Department of Physics COMSATS Institute of Information Technology Department of mechanical and materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Basic Sciences and Humanities Muhammad Nawaz Sharief University of Engineering and Technology(MNSUET) Department of mechanical Engineering COMSATS Institute of Information Technology Department of Physics The Islamia University of Bahawalpur

Due to current trend and increasing interest towards natural based fiber products, Kenaf(Hibiscus cannabinus)fibers have been used for the developments of many products. Therefore, Kenaf fiber-reinforced composites have been widely used in engineering and industrial applications. The present work deals with the fabricating and characterization of untreated and treated kenaf/polypropylene(PP)-reinforced composites. Composites of PP reinforced with treated and untreated kenaf fibers were fabricated using the injection molding *** fiber loadings of 10, 20, 30, 40, 50 wt% treated and untreated kenaf composites were also prepared. Xray diffraction(XRD), scanning electron microscopy(SEm), Fourier transform infrared(FTiR) spectroscopy and thermo gravimetric analysis(TGA) were performed on the treated, untreated kenaf fibers and kenaf/PP composites. moreover, the alkaline-treated kenaf composites exhibit better physical, morphological, and mechanical properties because of the compatibility of kenaf with PP. However, variations in tensile and flexural properties depend on treatment and kenaf fiber contents. The percentage increase in the mechanical properties of the treated kenaf/PP composites relative to that of PP was also measured. in addition, 40 wt%kenaf fiber loading resulted in higher mechanical properties. By contrast, kenaf/PP composite with 50% fiber loading was not successfully prepared because of improper mixing and the burning of kenaf fibers in the PP matrix. To conclude, 40% kenaf/PP composites with superior physical and mechanical properties may be used in variety of applications such as automotive, sports, construction, animal bedding, and mass production industries.

关键词： Kenaf composites microstructures Physical properties mechanical Testing injection-molding

investigation on the key aspects of l-arginine para nitrobenzoate monohydrate single crystal:A non-linear optical material

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Chinese Journal of Chemical Engineering 2019年第3期27卷 701-708页

作者： Sonia n.Vijayan mahak Vij Kanika Thukral naghma khan D.Haranath Rajnikant m.S.Jayalakshmy Academy of Scientific and innovative Research CSIR-National Physical Laboratory CSiR-national Physical Laboratory Department of Physics University of Jammu international and inter University Centre for nanoscience and nanotechnology Mahatma Gandhi University

in the contemporary days, non-linear optical materials(nLO) are getting higher attention as per the increasing demand in optical communication and data storage technology. Consequently, they explore various physical properties of the nLO material for their industrial applications. in current report, l-arginine p-nitrobenzoate monohydrate(LAnB) single crystals were obtained by adopting slow cooling technique. The structural confirmation of grown single crystal was carried out using single crystal X-Ray diffractometer. Presence of strain within single crystal was deduced using Hall–Williamson relation. Various defects associated within single crystal were assessed using high resolution XRD. Additionally, its crystalline quality was again confirmed by time resolved photoluminescence spectroscopy(TRPL). Using transmission spectra, the cut off wavelength and band gap of the host material was determined to be nearly 420 nm and 2.9 e V respectively. The dielectric property has been recorded by varying the frequency ranging from 50 Hz to 100 k Hz. The curve suggests that dielectric loss value is less at high frequency ensures the suitability of crystal in photonics and nLO based *** laser damage threshold values were also measured for single and multiple shots. Thermal parameters of the titled compound were calculated using PPE. in photoconductivity measurement, negative photoconductivity has been observed in titled compound. microhardness studies were also performed on single crystal to explore its mechanical properties.

关键词： Photoluminescence Thermal conductivity Specific heat Thermal effusivity Damage threshold

metabolic complications of psychotropic medications in psychiatric disorders:Emerging role of de novo lipogenesis and therapeutic consideration

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World Journal of Psychiatry 2024年第6期14卷 767-783页

作者： mohammad m khan Zaw Ali khan mohsin Ali khan Laboratory of Translational neurology and molecular Psychiatry Department of BiotechnologyEra’s Lucknow Medical College and Hospitaland Faculty of ScienceEra UniversityLucknow 226003India Era’s Lucknow medical College and Hospital Era UniversityLucknow 226003India

Although significant advances have been made in understanding the pathophysiology of psychiatric disorders(PDs),therapeutic advances have not been very *** psychotropic medications can reduce classical symptoms in patients with PDs,their long-term use has been reported to induce or exaggerate various pre-existing metabolic abnormalities including diabetes,obesity and non-alcoholic fatty liver disease(nAFLD).The mechanism(s)underlying these metabolic abnormalities is not clear;however,lipid/fatty acid accumulation due to enhanced de novo lipogenesis(DnL)has been shown to reduce membrane fluidity,increase oxidative stress and inflammation leading to the development of the aforementioned metabolic ***,emerging evidence suggest that DnL dysregulation and fatty acid accumulation could be the major mechanisms associated with the development of obesity,diabetes and nAFLD after long-term treatment with psychotropic medications in patients with *** support of this,several adjunctive drugs comprising of anti-oxidants and antiinflammatory agents,that are used in treating PDs in combination with psychotropic medications,have been shown to reduce insulin resistance and development of *** conclusion,the above evidence suggests that DnL could be a potential pathological factor associated with various metabolic abnormalities,and a new avenue for translational research and therapeutic drug designing in PDs.

关键词： Psychotropic medications metabolic complications De novo lipogenesis Obesity Diabetes non-alcoholic fatty liver disease

Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed m.ATTA Reda n.BEHiRY mohammed i.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt nile Higher institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

Spatial distribution and source identification of heavy metal pollution in roadside surface soil:a study of Dhaka Aricha highway,Bangladesh

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Ecological Processes 2016年第1期5卷 16-31页

作者： Fahad Ahmed A.n.m.Fakhruddin m.D.Toufick imam nasima khan Tanzir Ahmed khan md.mahfuzur Rahman Abu Tareq mohammad Abdullah Department of Environmental Sciences Jahangirnagar UniversitySavarDhaka 1342Bangladesh institute of Food Science&Technology(iFST) Bangladesh Council of Scientific&Industrial Research(BCSIR)DhakaBangladesh

introduction:in this study,metal pollution and their sources in surface soils were evaluated by pollution indices and multivariate statistical techniques in association with a geographical information system(GiS).methods:Surface soil samples were collected in dry season from different locations of Dhaka Aricha highway and analyzed by energy dispersive X-ray fluorescence(EDXRF).Results:Thirteen different metals were found in the tested *** indices are determined by enrichment factor in an order of Zr>Sn>P>mn>Zn>Rb>Fe>Ba>Sr>Ti>K>Ca>*** resulting geoaccumulation index(igeo)value shows the following order:Sn>Zr>P>mn>Zn>Rb>Fe>Ba>Ti>Sr>K>Ca>*** factors(CFs)of the metals range from 1.422 to 3.979(Fe);0.213 to 1.089(Al);0.489 to 3.484(Ca);1.496 to 2.372(K);1.287 to 3.870(Ti);2.200 to 14.588(mn);5.938 to 56.750(Zr);0.980 to 3.500(Sr);2.321 to 4.857(Rb);2.737 to 6.526(Zn);16.667 to 27.333(Sn);3.157 to 16.286(P);and 0.741 to 3.328(Ba).Pollution load index calculated from the CFs indicates that soils are strongly contaminated by Zr and *** component analysis(PCA)of parameters exhibits three major components.R-mode cluster analysis reveals three distinct groups in both site and metal basis clustering that shows a similar pattern with the ***:These results might be helpful for future monitoring of further increase of heavy metal concentrations in surface soils along highways.

关键词： Heavy metals Geoaccumulation index(i_(geo)) Contamination factor(CF) Pollution load index(PLi) Principal component analysis(PCA) Dhaka Aricha highway

Environmental screening and ligand-field effects to magnetism in Cri_(3) monolayer

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npj Computational materials 2021年第1期7卷 1481-1490页

作者： D.Soriano A.n.Rudenko m.i.Katsnelson m.Rösner Radboud University Institute for Molecules and MaterialsHeyendaalseweg 1356525 AJ NijmegenThe Netherlands Universitàdi Pisa Dipartimento di Ingegneria dell’InformazioneVia Caruso56122 PisaItaly Department of Theoretical Physics and Applied mathematics Ural Federal University620002 EkaterinburgRussia

We study the microscopic origin of magnetism in suspended and dielectrically embedded Cri_(3)monolayer by down-folding minimal generalized Hubbard models from ab initio calculations using the constrained random phase *** models are capable of describing the formation of localized magnetic moments in Cri_(3)and of reproducing electronic properties of direct ab initio *** the magnet force theorem,we find a multi-orbital super-exchange mechanism as the origin of magnetism in Cri_(3)resulting from an interplay between ferro-and anti-ferromagnetic Cr-Cr d coupling channels,which is decisively affected by the ligand p *** show how environmental screening,such as resulting from encapsulation with hexagonal boron nitride,affects the Coulomb interaction in the film and how this controls its magnetic *** by a non-monotonic interplay between nearest and next-nearest neighbor exchange interactions we find the magnon dispersion and the Curie temperature to be non-trivially affected by the environmental screening.

关键词： properties monolayer exchange

Shocks and Solitons in Ultradense Degenerate Electron-Positron-ion Plasmas

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Communications in Theoretical Physics 2011年第1期55卷 151-157页

作者： S.A.khan Arshad m.mirza national Centre for Physics Quaid-i-Azam University Campusand Department of PhysicsCOMSATS Institute of Information Technology Theoretical Plasma Physics Group Department of PhysicsQuaid-i-Azam University

The formation and propagation of shocks and solitons are investigated in an unmagnetized, ultradense plasma containing degenerate Fermi gas of electrons and positrons, and classical ion gas by employing Thomas-Fermi model. For this purpose, a deformed Korteweg-de Vries-Berger （dKdVB） equation is derived using the reductive perturbative technique for cold, adiabatic, and isothermal ions. Localized analytical solutions of dKdVB equation in planar geometry are obtained for dispersion as well as dissipation dominant cases. For nonplanar （cylindrical and spherical） geometry, time varying numerical shock wave solution of dKdVB equation is found. its dispersion dominant case leading to the soliton solution is also discussed. The effect of ion temperature, positron concentration and dissipation is found significant on these nonlinear structures. The relevance of the results to the systems of scientific interest is pointed out.

关键词： degenerate plasma nonplanar geometry shocks solitons

Assessing fracturing mechanisms and evolution of excavation damaged zone of tunnels in interlocked rock masses at high stresses using a finitediscrete element approach

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Journal of Rock mechanics and Geotechnical Engineering 2019年第4期11卷 701-722页

作者： i.Vazaios n.Vlachopoulos m.S.Diederichs Arup LondonW1T 4BQUnited Kingdom Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonOntarioK7L 3N6Canada Department of Civil Engineering Royal Military College of CanadaKingstonOntarioK7L 4V3Canada

Deep underground excavations within hard rocks can result in damage to the surrounding rock mass mostly due to redistribution of *** within rock masses with non-persistent joints,the role of the pre-existing joints in the damage evolution around the underground opening is of critical importance as they govern the fracturing mechanisms and influence the brittle responses of these hard rock masses under highly anisotropic in situ *** this study,the main focus is the impact of joint network geometry,joint strength and applied field stresses on the rock mass behaviours and the evolution of excavation induced damage due to the loss of confinement as a tunnel face *** of such a phenomenon was conducted using the finite-discrete element method (FDEm).The numerical model is initially calibrated in order to match the behaviour of the fracture-free,massive Lac du Bonnet granite during the excavation of the Underground Research Laboratory (URL) Test Tunnel,*** influence of the pre-existing joints on the rock mass response during excavation is investigated by integrating discrete fracture networks (DFns) of various characteristics into the numerical models under varying in situ *** numerical results obtained highlight the significance of the pre-existing joints on the reduction of in situ rock mass strength and its capacity for extension with both factors controlling the brittle response of the ***,the impact of spatial distribution of natural joints on the stability of an underground excavation is discussed,as well as the potentially minor influence of joint strength on the stress induced damage within joint systems of a non-persistent nature under specific ***,the in situ stress-joint network interaction is examined,revealing the complex fracturing mechanisms that may lead to uncontrolled fracture propagation that compromises the overall stability of an underground excavation.

关键词： Excavation damaged zone (EDZ) Brittle failure Finite-discrete element method (FDEm) Tunnelling Discrete fracture network (DFn)

microtubule as a Transmission Line for ionic Currents

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Chinese Physics Letters 2009年第7期26卷 97-99页

作者： iliC D.i. SatariC m.V RaleviC n. Faculty of Technical Sciences University of Novi SadTrg D.Obradovica 621000 Novi SadSerbia

We establish a new model for ionic waves along microtubules based on polyelectrolyte features of cylindrical biopolymers. The nonlinear transmission line described by a nonlinear differential equation is obtained with stable kink solution pertinent to the shape of the front of accompanying potential. The localized ionic wave could be used to explain the behavior of microtubules as biomolecular transistors capable of amplifying electrical information in neurons.

关键词： Electronics and devices Biological physics