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Indirect photocatalytic reduction of arsenate to arsenite in aqueous solution with TiO_2 in the presence of hole scavengers

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Chinese Journal of Chemical Engineering 2018年第3期26卷 529-533页

作者： Abdus Samad shamim Ahsan Ikki Tateishi Mai Furukawa Hideyuki Katsumata Tohru Suzuki Satoshi Kaneco Department of Chemistry Jagannath University Department of Earth and Atmospheric Sciences Metropolitan State University of Denver Department of Chemistry for Materials Graduate School of Engineering Mie University Mie Global Environment Center for Education & Research Mie University

The indirect photocatalytic reduction of arsenate to arsenite in aqueous solution with titanium dioxide(TiO_2)was investigated with various hole scavengers such as methanol, ethanol, 2-propanol, formaldehyde, acetone,formic acid and acetic acid. Although the direct photocatalytic reduction of arsenate to arsenite with TiO_2 was impossible, an indirect reduction of As(V) was possible in the presence of sacrificial electron donors to form strongly reductive radicals. The addition of ethanol was very effective for indirect photocatalytic reduction of As(V) in aqueous solution with TiO_2 photocatalyst. The indirect photocatalytic reduction rate of As(V) may be related with both the reaction rate constants of reaction of hydroxyl radicals with hole scavenger and the reactivities for the radicals M· which are produced by the reaction of ·OH with hole scavenger.

关键词： Indirect photocatalytic reduction Arsenate Arsenite Titanium dioxide Hole scavenger

Biogeochemical evaluation of Nannorrhops ritchiana: A Mg-flora from Khuzdar, Balochistan, Pakistan

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Chinese Journal Of Geochemistry 2005年第4期24卷 327-337页

作者： Sadaf Naseem Shahid Naseem Erum Bashir Khaula Shirin shamim A. Sheikh Department of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanPCSIR Laboratories Complex off University Road Karachi PakistanDepartment of Geology University of Karachi Karachi 75270 Pakistan

Nannorrhops ritchiana (Mazari Palm) is a distinctive flora growing in the Saharo-Sindian region. It is well distributed on the ultramafic soil, derived from the Bela Ophiolite in the Khuzdar District, Balochistan, Pakistan. Quantitative estimation of Ca, Mg, Fe and Ni in soil and plant ash has been carried out. The constituents of plant ash have been discussed in relation to soil chemistry, pH, climate, mobility, average abundance in plant ash and exclusion mechanism of the flora. Relationship among Ca, Mg, Fe and Ni has been established using scattergrams to evaluate the biogeochemistry of the plant. High contents of Mg and high coefficient of biological absorption allow it to be classed as Mg-flora. Both Ca and Fe appeared to be antagonistic to Mg. The metal assemblage of N. ritchiana nicely reflected the nature of the bed rock as being serpentinized ultramafic, and its corresponding soils. Good exclusion mechanism of N. ritchiana did not allow it to absorb high Ni from the soil. Relatively high concentrations of Ni in N. ritchiana from the Baran Lak area can be used to localize Ni-mineralization in the study area.; Statistical analyses, such as minimum, maximum, mean, mode, median, standard deviations, and coefficient of correlation, were also made to improve raw geochemical data and interpretations.

关键词：巴基斯坦生物化学超碱土壤土壤化学

Abundant general solitary wave solutions to the family of KdV type equations

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Journal of Ocean Engineering and Science 2017年第1期2卷 47-54页

作者： Md.Azmol Huda M.Ali Akbar Shewli shamim Shanta Mathematics Discipline Khulna UniversityKhulnaBangladesh Department of Applied Mathematics University of RajshahiRajshahiBangladesh Department of Mathematics University of RajshahiRajshahiBangladesh

This work explores the construction of more general exact traveling wave solutions of some nonlinear evolution equations(NLEEs)through the application of the(G/G,1/G)-expansion *** method is allied to the widely used(G/G)-method initiated by Wang et *** can be considered as an extension of the(G/G)-expansion *** effectiveness,the method is applied to the family of KdV type *** general form solitary wave solutions as well as periodic solutions are successfully obtained through this ***,in the obtained wider set of solutions,if we set special values of the parameters,some previously known solutions are *** approach of this method is simple and elegantly *** been computerized it is also powerful,reliable and effective.

关键词： Nonlinear evolution equation Solitary wave solution Potential KdV equation Complex modified KdV equation

The new types of wave solutions of the Burger’s equation and the Benjamin-Bona-Mahony equation

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Journal of Ocean Engineering and Science 2018年第1期3卷 1-10页

作者： Md.Azmol Huda M.Ali Akbar Shewli shamim Shanta Mathematics Discipline Khulna UniversityBangladesh Department of Applied Mathematics University of RajshahiBangladesh Department of Mathematics University of RajshahiBangladesh

In this article,we suggest the two variable(G/G,1/G)-expansion method for extracting further general closed form wave solutions of two important nonlinear evolution equations(NLEEs)that model one-dimensional internal waves in deep water and the long surface gravity waves of small amplitude propagating *** method can be regarded as an extension of the(G/G)-expansion *** ansatz of this extension method to obtain the solution is based on homogeneous balance between the highest order dispersion terms and nonlinearity which is similar to the(G/G)method whereas the auxiliary linear ordinary differential equation(LODE)and polynomial solution *** applied this method to find explicit form solutions to the Burger’s and Benjamin-Bona-Mahony(BBM)equations to examine the effectiveness of the method and tested through mathematical computational software *** new exact travelling wave solutions in more general form of these two nonlinear equations are derived by this extended *** method introduced here appears to be easier and faster comparatively by means of symbolic computation system.

关键词： Travelling wave solution Soliton Burger’s equation Benjamin-Bona-Mahony equation.

New Levels of the Pr Atom with Almost Similar Energies

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Journal of Physical Science and Application 2012年第4期2卷 88-94页

作者： Zaheer uddin Imran Siddiqui shamim Khan B. Gamper Esam H.Abdul-Hafidh L. Windholz Institute for Experimental Physics Univ. of Technology Graz Austria Departement of Physics Yanbu University College Yanbu AI Sanaiyah Saudi Arabia Department of Physics University of Karachi Karachi Pakistan

A Fourier transform （FT） spectrum of praseodymium （Pr） extending from UV to IR was investigated. Hyperfine （hf） structures of unclassified lines with sufficiently high signal to noise ratio （SNR） were analyzed and some new levels were found. We present these new levels in this work. Some of the new levels have energies almost equal to the energies of already known or other new levels, distinguished either by different values of angular momentum J or by their parity.

关键词： Hyperfine structure praseodymium fourier spectrum.

Evaluation of structure,dielectric and electrical properties of(Li/Ta/Sb)modified(Na,K)NbO_(3) lead-free ceramics with excess Na concentration

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Journal of Advanced Dielectrics 2017年第6期7卷 12-20页

作者： Md.Kashif shamim Arpana Singh Seema Sharma Materials Research Laboratory Department of Physics A.N CollegePatna 800013India

Polycrystalline perovskite structured Li_(0.04)(Na_(0.54+x) K_(0.46))_(0.96)(Nb_(0.81)Ta_(0.15)Sb_(0.04))O_(3) ceramics with x¼0:00,0.005 and 0.01 mole excess Na concentration were prepared by solid state sintering *** present study relates the role of excess Na addition with the stoichiometry,density,structure,dielectric and ferroelectric properties of the samples.X-ray diffraction(XRD)pattern exhibits single phase orthorhombic *** characteristic Raman modes were observed due to translational modes of cations and vibrational modes of NbO_(6) octahedra and no structural phase transition were *** confirms the formation of single phase perovskite structure and is consistent with XRD *** dielectric permittivity increases about two times,while dielectric loss decreases by four times for χ=0.01 *** electrical measurements carried by Complex Impedance spectroscopic analysis suggest negative temperature coefficient of resistance(NTCR)behavior.

关键词： Perovskite dielectric properties negative temperature coefficient of resistance(NTCR) ferroelectric properties leakage current

Building the metaverse using digital twins at all scales,states,and relations

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Virtual Reality & Intelligent Hardware 2022年第6期4卷 459-470页

作者： Zhihan LV Shuxuan XIE Yuxi LI M.shamim HOSSAIN Abdulmotaleb El SADDIK Department of Game Design Faculty of ArtsUppsala UniversitySweden College of Computer Science and Technology Qingdao UniversityQingdaoChina Department of Software Engineering College of Computer and Information SciencesKing Saud UniversityRiyadhSaudi Arabia School of Electrical Engineering and Computer Science(EECS) University of OttawaOttawaOntarioCanada

Developments in new-generation information technology have enabled Digital Twins to reshape the physical world into a virtual digital space and provide technical support for constructing the *** objects can be at the micro-,meso-,or *** Metaverse is a complex collection of solid,liquid,gaseous,plasma,and other uncertain ***,the Metaverse integrates tangibles with social relations,such as interpersonal(friends,partners,and family)and social relations(ethics,morality,and law).This review introduces some principles and laws,such as broken windows theory,small-world phenomenon,survivor bias,and herd behavior,for constructing a Digital Twins model for social ***,from multiple perspectives,this article reviews mappings of tangible and intangible real-world objects to the Metaverse using the Digital Twins model.

关键词： Digital twins Metaverse Sensor

Impact of rangeland enclosure and seasonal grazing on protected and unprotected rangelands in Chakwal region, Pakistan

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Journal of Mountain Science 2022年第4期19卷 46-57页

作者： ISLAM Muhammad RAZZAQ Abdul ZUBAIR Muhammad HASSAN Sawsan AHMAD Sarfraz GUL shamim RISCHKOWSKY Barbara LOUHAICHI Mounir International Center for Agricultural Research in Dry Areas(ICARDA) South AsiaIslamabad 44050Pakistan Animal Science Division Pakistan Agricultural Research CouncilIslamabad 44050Pakistan Department of Forestry and Range Management Bahauddin Zakariya UniversityMultan 66000Pakistan International Center for Agricultural Research in Dry Areas(ICARDA) Amman 11185Jordan Natural Resource Division Pakistan Agricultural Research CouncilIslamabad 44050Pakistan Botany Department University of Balochistan Quetta 87300Pakistan Department of Natural Resource Sciences McGill UniversityQuebec H9X3V9Canada International Center for Agricultural Research in Dry Areas(ICARDA) SSAILRI campusAddis Ababa 5689Ethiopia International Center for Agricultural Research in Dry Areas(ICARDA) Tunis 1004Tunisia

Scrub rangelands support livestock grazing and provide ecosystem services to their inhabitants. The present study was conducted in Chakwal, an important tract of the Pothwar Plateau,which sustains herds of small domestic and nomadic ruminants. Urbanization and uncontrolled grazing practices have reduced rangeland productivity and increased soil erosion and resulted in poor land conditions. This study assessed the influence of two years of rangeland protection on aboveground vegetation biomass and the chemical composition of plants and aimed to determine the influence of seasonal grazing on the live-weight gain of small *** the line intercept method, vegetation data from protected and unprotected plots in 2015 and 2016 were collected at two sites, Dhulli and *** cover was assessed from images using VegMeasure. Results showed that protected study sites displayed higher vegetation biomass(834 and 690 kg ha^(-1)) compared to the unprotected study site(477 and 326 kg ha^(-1)) during April and August of both years. In the seasonal grazing trial, the experimental ewes that grazed on protected rangelands showed higher live-weight gain(33–63 g day^(-1)) compared to live weight of ewes(17–21 g day^(-1)) that grazed on unprotected rangelands during the experimental period of 127 days at both sites. The results suggest that the Chakwal rangeland has tremendous potential to improve vegetation productivity but modern livestock management and seasonal grazing practices are needed to improve carrying capacity and livestock productivity.

关键词： Seasonal grazing Climate change Productivity Rangeland Protected area

The Effects of Spherical Surface and Laser Polarization on the Photodetachment Cross Section of H^-

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Communications in Theoretical Physics 2013年第3期59卷 356-360页

作者： Muhammad Haneef Suneela Arif Jehan Akbar Nasrullah Shah Muhammad Zahir Aneela shamim Hameed Ullah Lab of Atom and Quantum Interference Department of PhysicsHazara UniversityGarden CampusMansehraPakistan Department of Chemistry Abdul Wali Khan UniversityMardanPakistan Department of Statistics University of PeshawarPakistan Department of Chemistry Hazara UniversityGarden CampusMansehraPakistan

We report the combined effects of laser polarization and curvature of the spherical surface on the detached electron spectra from H-. The Theoretical imaging method is used as a tool of investigation. The photodetachment cross sections for various polaxization angles, radii of curvatures and inter ion surface distances axe displayed. The analysis of the spectra reveals that the laser polarization angle θL, curvature of the surface τc and inter ion surface distance d strongly affect oscillations in the spectra. Therefore, a fine control on the laser polaxization and that of curvature in the surface can be used to control oscillations in the photodetachment of negative ions.

关键词： negative ions photodetachment spherical surface