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UV RADIATION INDUCED GRAFT COPOLYmERIZATION OF ALLYL ACETATE ONTO POLY(EThYLENE TEREPhThALATE)(PET) FILmS FOR FUEL CELL mEmBRANES

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Chinese Journal of Polymer Science 2012年第2期30卷 227-234页

作者： mostak Ahmed mubarak A.khan Nazia Rahman m.anwar h.khan Radiation and Polymer Chemistry Laboratory Institute of Nuclear Science and TechnologyBangladesh Atomic Energy CommissionP.O.Box 3787DhakaBangladesh Department of Chemistry Shahjalal University of Science and TechnologySylhet-3114Bangladesh Department of Geography University of California BerkeleyBerkeleyCA 94720USA

Ultraviolet （UV）-induced graft copolymerization of allyl acetate （AA） monomer onto poly（ethylene terephthalate）（PET） films and the subsequent sulfonation on the monomer units in the grafting chain using chlorosulfonic acid （C1SO3h） were carried out to prepare proton exchange membranes （PEms） for fuel cells. A maximum grafting value of 12.8% was found for 35 vol% allyl acetate after 3 h radiation time. Optimum concentration of C1SO3h was selected for the sulfonation reaction to be 0.05 mol/L based on the degree of sulfonation and the tensile strength studies of the membrane. The degree of sulfonation increased as the sulfonation reaction temperature and sulfonation time were increasing. The radiation grafting and the sulfonation have been confirmed by titrimetric and gravimetric analyses as well as FTIR spectroscopy. The maximum ion exchange capacity （IEC） of 0.04125 mmol g-1 was found at 12.1% degree of sulfonation and the maximum proton conductivity was found to be 0.035 S cm-1 at 30℃ and a relative humidity of 60%. The various physical and chemical properties of the PEms such as water uptake, mechanical strength, thermal durability and oxidative stability were also studied. To investigate the suitability of the prepared membrane for fuel cell applications, its properties were compared with those ofNafion 117.

关键词： Polymer electrolyte membrane Allyl acetate Fuel cell UV radiation Grafting Sulfonation.

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Estimation and comparison of night-time Oh levels in the UK urban atmosphere using two different analysis methods

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Journal of Environmental Sciences 2011年第1期23卷 60-64页

作者： m.anwar h.khan m.m.Nazmul hoque S.Shamsul Alam m.J.Ashfold Graham Nickless Dudley E.Shallcross School of Chemistry University of BristolBS8 1TSUnited Kingdom Department of Geography University of California Berkeley540 McCone HallBerkeleyCA 94720USA Department of Chemistry Shahjalal University of Science and TechnologySylhet-3114Bangladesh

Night-time Oh levels have been determined for UK urban surface environments using two methods, the decay and steady state approximation methods. measurement data from the UK National Environmental Technology Centre archive for four urban sites （Bristol, harwell, London Eltham and Edinburgh） over the time period of 1996 to 2000 have been used in this study. Three reactive alkenes, namely isoprene, 1,3-butadiene and trans-2-pentene were chosen for the calculation of Oh levels by the decay method. hourly measurements of NO, NO〉 03, CO and 20 VOCs were used to determine night-time Oh level using the steady state approximation method. Our results showed that the night-time Oh levels were in the range of 1 × 10^3-1× 10^6 molecules/cm3 at these four urbap sites in the UK. The application of a t-test of these analyses indicated that except Bristol, there was no significant difference between the Oh levels found from the decay and steady state approximation methods. Night-time levels of the Oh radical appeared to peak in summer and spring time tracking the night-time 03 levels which also passed through a maximum at this time.

关键词： night-time urban National Environmental Technology Center steady state approximation hydrocarbon decay method

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Plastic mulch increases dryland wheat yield and water-use productivity,while straw mulch increases soil water storage

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Journal of Integrative Agriculture 2024年第9期23卷 3174-3185页

作者： hubing Zhao Guanfei Liu Yingxia Dou huimin Yang Tao Wang Zhaohui Wang Sukhdev malhi Adnan anwar khan College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture and Rural AffairsYangling 712100China Department of Renewable Resources University of AlbertaEdmonton T6G 2H1Canada

Amplifying drought stress and high precipitation variability impair dryland wheat *** problems can potentially be minimized by using plastic mulch(Pm)or straw mulch(Sm).Therefore,wheat grain yield,soil water storage,soil temperature and water-use productivity of Pm and Sm treatments were compared with no mulch(CK)treatment on dryland wheat over a period of eight *** to the CK treatment,Pm and Sm treatments on average significantly increased grain yield by 12.6 and 10.5%,*** to the CK treatment,Sm treatment significantly decreased soil daily temperature by 0.57,0.60 and 0.48℃ for the whole seasons,growing periods and summer fallow periods,*** contrast,compared to the CK treatment,Pm treatment increased soil daily temperature by 0.44,0.51 and 0.27℃ for the whole seasons,growing periods and summer fallow periods,*** soil temperature under Sm allowed greater soil water storage than under *** water storage pre-seeding was 17%greater under the Sm than under the Pm *** water storage post-harvest was similar for the Pm and Sm treatments,but evapotranspiration was 4.5%higher in the Sm than in the Pm ***,water-use productivity was 6.6%greater under Pm than under the Sm ***,Pm treatment increased dryland wheat yield and water-use productivity,while straw mulch increased soil water storage.

关键词： plastic mulch soil water storage straw mulch water-use productivity winter wheat

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Perception beyond sight:Investigating the cognitive maps of congenitally blind individuals in urban environments

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Frontiers of Architectural Research 2024年第4期13卷 809-821页

作者： anwar Ibrahim hikmat hAli Zainab mahmoud College of Architecture and Design Jordan University of Science and TechnologyIrbidJordan College of Engineering and Architecture Al Yamamah UniversityRiyadhKSA

This study explores the challenges faced by congenitally blind individuals in navigating urban ***,this research investigates the factors that contribute to the construction of city mental mapping for individuals who are born ***-one congenitally blind individuals from the University of Jordan were asked to define and describe specific elements of the city based on their personal experiences and ***,participants were guided through two urban paths:familiar and *** participants were asked to complete a survey regarding their experiences during the *** collected data was analyzed by using thematic *** results revealed that congenitally blind individuals construct their mental image of the city by using their three senses of touching,hearing,and smelling,as well as their safety and *** mental image consists of five key elements:links,reference points,areas,separators,and *** the small size of the study sample and the specificity of the context,the results of this study will tremendously help planners in designing highly inclusive urban *** characteristics that can be recognized by the blinds will enhance their accessibility of urban spaces,encourage independent mobility,increase the quality of life and social inclusion for them.

关键词： mental map City image Congenital blind Cognitive mapping Environmental perception

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Experimental and computational study of annealed nickel sulfide quantum dots for catalytic and antibacterial activity

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Nano materials Science 2024年第3期6卷 355-364页

作者： muhammad Ikram Sawaira moeen Ali haider anwar Ul-hamid haya Alhummiany hamoud h.Somaily Souraya Goumri-Said mohammed Benali Kanoun Solar Cell Applications Research Lab Department of PhysicsGovernment College University LahoreLahore54000PunjabPakistan Department of Clinical Sciences Faculty of Veterinary and Animal SciencesMuhammad Nawaz ShareefUniversity of Agriculture66000MultanPunjabPakistan Core Research Facilities King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics Faculty of ScienceUniversity of JeddahP.O.Box 13151Jeddah21493Saudi Arabia Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Physics Department College of Science and General StudiesAlfaisal UniversityP.O.Box 50927Riyadh11533Saudi Arabia Department of mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia

This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide(NiS_(2) quantum dots(QDs)for catalytic decolorization of methylene blue(mB)dye and antimicrobial *** size increased with longer annealing,reducing catalytic ***–vis,XRD,TEm,and FTIR analyses probed optical structural,morphological,and vibrational *** confirmed NiS2's anorthic structure,with crystallite size growing from 6.53 to 7.81 nm during extended ***–Vis exhibited a bathochromic shift,reflecting reduced band gap energy(Eg)in NiS_(2).TEm revealed NiS_(2)QD formation,with agglomerated QD average size increasing from 7.13 to 9.65 nm with prolonged *** NiS_(2) showed significant mB decolorization(89.85%)in acidic *** NiS_(2) QDs demonstrated notable antibacterial activity,yielding a 6.15mm inhibition zone against Escherichia coli(***)compared to ***-principles computation supported a robust interaction between mB and NiS_(2),evidenced by obtained adsorption *** study highlights the nuanced relationship between annealing duration,structural changes,and functional properties in NiS_(2)QDs,emphasizing their potential applications in catalysis and antibacterial interventions.

关键词： NiS_(2) antibacterial quantum dots dye degradation DFT

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Ultrahydrophobic melamine sponge via interfacial modification with reduced graphene oxide/titanium dioxide nanocomposite and polydimethylsiloxane for oily wastewater treatment

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Water Science and Engineering 2024年第2期17卷 139-149页

作者： hamidatu Alhassan Ying Woan Soon anwar Usman Voo Nyuk Yoong Department of Physics Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei Department of Chemical Sciences Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei

Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and *** their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of *** this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(mS)through interfacial modification using a solution immersion *** further modify it,poly-dimethylsiloxane(PDmS)was grafted onto its surface to establish stronger covalent bonds with the *** water contact angle of the sponge(rGO/TiO_(2)/PDmS/mS)was 164.2°,which satisfies the condition for *** evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf *** a result of the increased density of rGO/TiO_(2)/PDmS/mS,it recorded an initial capacity that was 2 g/g lower than the raw mS for crude oil *** raw mS retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDmS/mS retained 97%,suggesting good *** oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDmS/mS in oil-water *** a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.

关键词： Oily wastewater Reduced graphene oxide Polydimethylsiloxane(PDmS) Emulsion separation melamine sponge

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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Treadmill training in Parkinson's disease:possible role of prefrontal modifications in the improved cortical-subcortical network function

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Neural Regeneration Research 2024年第2期19卷 407-408页

作者： hao Ding Amgad Droby Abdul Rauf anwar Jeffrey m.hausdorff Bahman Nasseroleslami Anat mirelman Inbal maidan muthuraman muthuraman Department of Neurology University Hospital WürzburgWürzburgGermany Academic Unit of Neurology Trinity College Dublinthe University of DublinDublinIreland Department of Neurology Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Sagol School of Neuroscience Tel Aviv UniversityTel AvivIsrael Biomedical Engineering Centre UET Lahore(KSK Campus)LahorePakistan Laboratory for Early markers of Neurodegeneration(LEmON) Center for the Study of MovementCognitionand Mobility(CMCM)Neurological InstituteTel Aviv Sourasky Medical CenterTel AvivIsrael Department of Physical Therapy Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Rush Alzheimer’s Disease Center and Department of Orthopaedic Surgery Rush University Medical CenterChicagoILUSA

Parkinson’s disease(PD)is a complex neurodegenerative disorder characterized by a range of motor symptoms such as bradykinesia,resting tremor,rigidity,and postural instability,as well as non-motor symptoms,such as de... 详细信息

关键词： rigidity fatigue

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Cost-Efficient medium Frequency Propagation Research with Software Defined Radio

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World Journal of Engineering and Technology 2024年第1期12卷 158-169页

作者： Casey m. hess Sohail anwar Division of Business Engineering and Information Sciences and Technology Department of Electromechanical Engineering Technology Pennsylvania State University Altoona Campus Altoona Pennsylvania USA Division of Business Engineering and Information Sciences and Technology Department of Engineering Pennsylvania State University Altoona Campus Altoona Pennsylvania USA

medium Frequency radio holds significance in modern society as it supports broadcasting and individual communications in the public, government, and military sectors. Enhancing the availability and quality of these communications is only possible by enhancing the understanding of medium frequency propagation. While traditional methods of radio wave propagation research can have a high material demand and cost, software defined radio presents itself as a versatile and low-cost platform for medium frequency signal reception and data acquisition. This paper details a research effort that utilizes software defined radio to help characterize medium frequency signal strength in relation to ionospheric and solar weather propagation determinants. Signal strength data from seven medium frequency stations of unique transmission locations and varying transmission powers were retrieved in 24-hour segments via a receiving loop antenna, Airspy hF+ Discovery software defined radio, and SDR Sharp software interface network. Retrieved data sets were visualized and analyzed in mATLAB for the identification of signal strength trends, which were subsequently compared to historical ionospheric and space weather indices in pursuit of a quantifiable correlation between such indices and medium frequency signal strengths. The results of the investigation prove that software defined radio, when used in conjunction with a receiving antenna and data analysis program, provides a versatile mechanism for cost-efficient propagation research.

关键词： Ionosphere Space Weather Airspy SDR SDR Sharp mATLAB Analysis

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Crystallization of battery-grade lithium carbonate with high recovery rate via solid-liquid reaction

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Particuology 2024年第9期92卷 95-105页

作者： Chaofan Wu Longjin Jiang Wei Wang Bin Dong Zhidong Chang Daixiang Wei hira anwar minghui Zhang Dekun Gao School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing100083China Anhui Chaoyue Environmental Protection Technology Co. LtdChuzhou239060China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China Anhui huihong Technology Co. LtdChuzhou239060China

Lithium carbonate(Li_(2)CO_(3))stands as a pivotal raw material within the lithium-ion battery ***,we propose a solid-liquid reaction crystallization method,employing powdered sodium carbonate instead of its solution,which minimizes the water introduction and markedly elevates one-step lithium recovery *** kinetic calculations,the Li_(2)CO_(3)solid-liquid reaction crystallization process conforms by the Avrami equation rather than shrinking core model,which means the dissolution rate of Na_(2)CO_(3)is the most important factor affecting the reaction *** effects of reaction conditions such as temperature and stirring speed on the Li_(2)CO_(3)precipitation behavior were *** results indicated that temperature is a most essential parameter than other reaction conditions or stirring *** exceptional 93%recovery of Li_(2)CO_(3)at 90℃with a remarkable purity of 99.5%was achieved by using 1.2 m ratio of Na_(2)CO_(3)/Li_(2)SO_(4).This method provides a new idea for the efficient preparation of battery-grade Li_(2)CO_(3).

关键词： Lithium recovery Lithium sulfate Reaction crystallization Battery-grade lithium carbonate

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