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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.

A review of hydrogen technologies and engineering solutions for railway vehicle design and operations

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Railway Engineering Science 2021年第3期29卷 212-232页

作者： Yan Sun m.anwar N.m.S.Hassan maksym Spiryagin Colin Cole Centre for Railway Engineering Central Queensland UniversityRockhamptonQLDAustralia

Interest in hydrogen-powered rail vehicles has gradually increased worldwide over recent decades due to the global pressure on reduction in greenhouse gas emissions,technology availability,and multiple options of power *** the past,research and development have been primarily focusing on light rail and regional trains,but the interest in hydrogen-powered freight and heavy haul trains is also *** review shows that some technical feasibility has been demonstrated from the research and experiments on proof-of-concept *** rail vehicles powered by hydrogen either are currently operating or are the subject of experimental *** paper identifies that fuel cell technology is well developed and has obvious application in providing electrical traction power,while hydrogen combustion in traditional IC engines and gas turbines is not yet well *** need for on-board energy storage is discussed along with the benefits of energy management and control systems.

关键词： Hydrogen Fuel cells Hybrid power Rail vehicles Greenhouse gas emissions

Analysis of strong refractive effect within 11Li projectile structure

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Chinese Physics C 2021年第2期45卷 414-425页

作者： Kassem O.Behairy m.El-Azab Farid Awad A.Ibraheem Ola Ramadan m.anwar Physics Department Aswan UniversityAswan 81528Egypt Physics Department Assiut UniversityAssiut 71516Egypt Physics Department King Khalid UniversityAbhaSaudi Arabia Physics Department Al-Azhar UniversityAssiut 71524Egypt

In the context of the double folding optical model,the strong refractive effect for elastic scattering of 11Li+12C and 11Li+28Si systems at incident energies of 29,50,and 60 meV/n is *** folded potentials are generated based on a variety of nucleon-nucleon interactions with the suggested density distributions for the halo structure of 11Li *** rearrangement term(RT)of the extended realistic density dependent CDm3Y6 effective interaction is *** imaginary potential was taken in the traditional standard Woods-Saxon *** results for the calculated potentials are obtained,with a slight effect of the RT in CDm3Y6 *** reproduction with a normalization factor close to one for the observed angular distributions of the elastic scattering differential cross section has been achieved using the derived *** obtained reaction cross-section is studied as a guide by extrapolating our calculations and previous results.

关键词： optical model elastic and inelastic scattering halo nuclei folding model refraction effect

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

BioCluster:Tool for Identification and Clustering of Enterobacteriaceae Based on Biochemical Data

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Genomics, Proteomics & Bioinformatics 2015年第3期13卷 192-199页

作者： Ahmed Abdullah S.m.Sabbir Alam munawar Sultana m.anwar Hossain Department of microbiology University of Dhaka

Presumptive identifcation of different Enterobaeteriaeeae species is routinely achieved based on biochemical properties. Traditional practice includes manual comparison of each biochem- ical property of the unknown sample with known reference samples and inference of its identity based on the maximum similarity pattern with the known samples. This process is labor- intensive, time-consuming, error-prone, and subjective. Therefore, automation of sorting and sim- ilarity in calculation would be advantageous. Here we present a mATLAB-based graphical user interface （GUI） tool named BioCluster. This tool was designed for automated clustering and iden- tification of Enterobacteriaceae based on biochemical test results. In this tool, we used two types of algorithms, i.e., traditional hierarchical clustering （HC） and the Improved Hierarchical Clustering （IHC）, a modified algorithm that was developed specifically for the clustering and identification of within this species. IHC takes into account the variability in result of 1-47 biochemical tests family. This tool also provides different options to optimize the clus- tering in a user-friendly way. Using computer-generated synthetic data and some real data, we have demonstrated that BioCluster has high accuracy in clustering and identifying enterobacterial species based on biochemical test data. This tool can be freely downloaded at http：//***/ biocluster/.

关键词： Bacterial identification Enterobacteriaceae Biochemical properties Clustering tool Identification tool Hierarchy algorithm

Spatially Adaptive Image Restoration Using Fuzzy Punctual Kriging

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Journal of Computer Science & Technology 2007年第4期22卷 580-589页

作者： anwar m.mirza Asmatullah Chaudhry Badre munir Faculty of Cornputer Science and Engineering Ghulam Ishaq Khan(GIK)Institute of Engineering Science and Technology Topi-23460SwabiPakistan

We present a general formulation based on punctual kriging and fuzzy concepts for image restoration in spatial domain. Gray-level images degraded with Gaussian white noise have been considered. Based on the pixel local neighborhood, fuzzy logic has been employed intelligently to avoid unnecessary estimation of a pixel. The intensity estimation of the selected pixels is then carried out by employing punctual kriging in conjunction with the method of Lagrange multipliers and estimates of local semi-variances. Application of such a hybrid technique performing both selection and intensity estimation of a pixel demonstrates substantial improvement in the image quality as compared to the adaptive Wiener filter and existing fuzzykriging approaches. It has been found that these filters achieve noise reduction without loss of structural detail information, as indicated by their higher structure similarity indices, peak signal to noise ratios and the new variogram based quality measures.

关键词： image restoration fuzzy logic punctual kriging semivariance structure similarity index adaptive spatial filtering

mathematical modeling and parametric investigation of blood flow through a stenosis artery

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Applied mathematics and mechanics(English Edition) 2021年第11期42卷 1675-1684页

作者： A.ALI m.HUSSAIN m.S.anwar m.INC department of mathematics government college universityfaisalabad 38000pakistan department of natural sciences and humanities university of engineering and technologylahore 54890pakistan department of mathematics university of jhangistanbul 34295turkey department of computer engineering biruni universityIstanbul 34295Turkey department of mathematics firat universityelazig 23119turkey

In this study,a mathematical model is formulated to examine the blood flow through a cylindrical stenosed blood *** stenosis disease is caused because of the abnormal narrowing of flow in the *** narrowing causes serious health issues like heart attack and may decrease blood flow in the blood *** modeling helps us analyze such issues.A mathematical model is considered in this study to explore the blood flow in a stenosis artery and is solved numerically with the finite difference *** artery is an elastic cylindrical tube containing blood defined as a viscoelastic fluid.A complete parametric analysis has been done for the flow velocity to clarify the applicability of the defined ***,the flow characteristics such as the impedance,the wall shear stress in the stenotic region,the shear stresses in the throat of the stenosis and at the critical stenosis height are *** obtained results show that the intensity of the stenosis occurs mostly at the highest narrowing areas compared with all other areas of the vessel,which has a direct impact on the wall shear *** is also observed that the resistive impedance and wall shear pressure get the maximum values at the critical height of the stenosis.

关键词： stenotic artery blood flow finite difference method Navier-Stokes equation

Saponins and solvent extracts from Atriplex laciniata L. exhibited high anthelmintic and insecticidal activities

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Journal of Traditional Chinese medicine 2017年第5期37卷 599-606页

作者： Zul kamal Farhat Ullah Sajjad Ahmad muhammad Ayaz Abdul Sadiq muhammad Imran Shujat Ahmad Faiz Ur Rahman anwar Zeb Department of Pharmacy Shaheed Benazir Bhutto University Sheringal Dir Upper 18050Pakistan Department of Pharmacy University of Malakand Chakdara Dir Lower 18000 Pakistan Department of Zoology Shaheed Benazir Bhutto University Sheringal Dir Upper 18050 Pakistan

OBJECTIVE: To investigate saponins and various solvent extracts from Atriplex laciniata(A. laciniata)against human parasites and various ***: The samples from A. laciniata used in the activities were crude saponins(*** F) and solvent samples including methanolic extract(*** F), ethyl acetate(*** F), choloroform(*** F),n-hexane(*** F) and water residual(*** F). Anthelmintic potentials of the samples were analyzed against Pheretima posthuma(earthworms) and Ascaridia galli(round worms) using contact toxicity method. Insecticidal activities were performed against Heterotermes indicola(termite), monomorium pharaonis(pharaoh ant), Tribolium castaneum(flour beetle) and Rhyzopertha dominica(grain borer) using standard ***: In anthelmintic assay, *** F and *** F were most effective against P. posthuma and A. gal-li with average death times of 25.62 and 29.65 min respectively. Likewise the anthelmintic assay, *** F and *** F were most effective against H. indicola causing 90.36% and 73.24% lethality respectively. Furthermore, in anti-Pharaoh activity *** F, *** F, *** F, *** F and *** F exhibited highest activity with LD50 of 78, 220, 260, 330 and > 800 mg/m L respectively. *** F and *** F were highly effective against R. dominica causing 80.11% and71.30% lethality respectively. *** F was found most active against T. ***: Our findings suggest that the *** F, *** F and *** F extracted from *** *** be the best options for the isolation of anthelmintic and bio-insecticidal compounds.

关键词： Saponins Atriplex Parasites Hetero termes indicola monomorium pharaonis Rhyzopertha dominica Tribolium castaneum

Physical and Dielectric Properties of Some Nonionic Surfactants

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Journal of materials Science & Technology 1998年第4期14卷 361-367页

作者： El-anwar, I.m. El-Henawii, S.A. National Research Center Dokki Cairo Egypt Faculty of Science Helwan University Egypt

Fatty acid esters have been prepared by reacting the acid C//1//8 with polyethylene glycols having varying numbers of oxyethylene units (4-88 units) by the direct esterification reaction method. Surface and interfacial tensions were studied at various experimental conditions, including, concentration, temperature and chemical constitution of the surfactant. Critical micelle concentrations (CmC), surface excess and residual area occupied by each surface active agent molecule A have been calculated by using Gibb's equations. CmC values range from 10 to 55 multiplied by 10** minus **5 mole/L for all studied agents, while the residual area occupied by each molecule varies from 0.6 to 1.5 nm**2. Variation of CmC of some of these agents with temperature have been also examined and the obtained data were used to calculate the heat of micellization delta H//m and the entropy change during micellization delta S//m. Values of delta H//m vary from 14.63 kJ/mole to 2.717 kJ/mole depending on the chemical constitution of the agent under consideration. The apparent dipole moments mu of three surfactant were measured following the Headstrand's method. (Edited author abstract) 23 Refs.

关键词： Surface active agents