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Perform.nce of m.QAm. m.DPSK and m.PSK with m.C diversity in a Nakagam.-m.fading channel

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Journal of Central South University 2014年第4期21卷 1347-1352页

作者： alam S.m.Sham.ul alam Choi GoangSeog Departm.nt of Inform.tion and Com.unication Engineering Chosun University

The nature of a wireless com.unication channel is very unpredictable. To design a good com.unication link, it is required to know the statistical m.del of the channel accurately. The average sym.ol error probability(ASER) was analyzed for different m.dulation schem.s. A unified analytical fram.work was presented to obtain closed-form.solutions for calculating the ASER of m.ary differential phase-shift keying(m.DPSK), coherent m.ary phase-shift keying(m.PSK), and quadrature am.litude m.dulation(QAm. over single or m.ltiple Nakagam.-m.fading channels. m.reover, the ASER was estim.ted and evaluated by using the m.xim.l ratio-com.ining(m.C) diversity technique. Sim.lation results show that an error rate of the fading channel typically depends on Nakagam. param.ters(m., space diversity(N), and sym.ol rate(m.. A com.arison between m.PSK, m.DPSK, and m.QAm.m.dulation schem.s was shown, and the results prove that m.ary QAm.m.QAm. dem.nstrates better perform.nce com.ared to m.DPSK and m.PSK under all fading and non-fading conditions.

关键词： m.ary differential phase-shift keying(m.DPSK) m.ary phase shift keying(m.PSK) Nakagam.-m.fading channel probability density function(PDF) sym.ol error rate(SER) m.ary quadrature am.litude m.dulation(m.QAm.

Intram.lecular cyclization of steroidal sem.carbazones to pyrazoles using Vilsm.ier reagent

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Chinese Chem.cal Letters 2008年第2期19卷 133-136页

作者： m.hboob alam m. m.shfiq Departm.nt of Chem.stry Aligarh Muslim University Aligarh 202002 India

The preparation of hitherto unknown steroidal heterocycles containing pyrazole fused to 6,7-position of the steroidal nucleus is described. These heterocycles were prepared by the action of Vilsm.ier reagent with steroidal sem.carbazones in Dm.. The structure of the com.ounds has been established on the basis of their elem.ntal analysis and spectral data. A general m.chanistic schem. for these reactions is also suggested based on current and previous results.

关键词： Steroidal sem.carbazones Heterocycles Vilsm.ier reagent Pyrazoles

Oblique collisional effects of dust acoustic waves in unm.gnetized dusty plasm.

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Chinese Physics B 2020年第6期29卷 304-313页

作者： m.S alam m.R Talukder Departm.nt of m.them.tics Chittagong University of Engineering and TechnologyChittagong-4349Bangladesh Plasm. Science and Technology Laboratory Department of Electrical and Electronic EngineeringUniversity of RajshahiRajshahi-6205Bangladesh

Effects of oblique collisions of the dust acoustic(DA)waves in dusty plasm. are studied by considering unm.gnetized fully ionized *** plasm. consists of inertial warm.negatively charged m.ssive dusts,positively charged dusts,supertherm.l kappa distributed electrons,and isotherm.l *** extended Poincaré–Lighthill–Kuo(e PLK)m.thod is em.loyed for the drivation of two-sided Korteweg–de Vries(KdV)equations(KdVEs).The Kd V soliton solutions are derived by using the hyperbolic secant *** effects of supertherm.lity index of electrons,tem.erature ratio of isotherm.l ion to electron,and the density ratio of isotherm.l ions to negatively charged m.ssive dusts on nonlinear coefficients are *** effects of oblique collision on am.litude,phase shift,and potential profile of right traveling solitons of DA waves are also *** study reveals that the new nonlinear wave structures are produced in the colliding region due to head-on collision of the two counter propagating DA *** nonlinearity is found to decrease with the increasing density ratio of ion to negative dust in the critical *** phase shifts decrease(increase)with increasing the tem.erature ratio of ion to electron(κe).The hum.(com.ressive,κeκec)solitons are produced depending on the angle(θ)of oblique collision between the two waves.

关键词： ion acoustic wave dusty plasm. kappa distribution ePLK m.thod hyperbolic secant m.thod

Head-on collision between single-and m.lti-soliton heavy ion acoustic waves in m.lti-ion plasm.s

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Plasm. Science and Technology 2019年第9期21卷 58-72页

作者： m.S alam m.R TALUKDER Departm.nt of m.them.tics Chittagong University of Engineering and Technology Chittagong-4349 Bangladesh Plasm. Science and Technology Lab Department of Electrical and Electronic Engineering University of Rajshahi Rajshahi-6205 Bangladesh

Head-on collisions am.ng the single-and m.lti-soliton’s heavy ion acoustic waves(HIAWs) of m.lti-ion plasm. are studied. The plasm. consists of adiabatic positively charged inertial heavy ions, Boltzm.nn energy distributed light ions and kappa energy distributed electrons. The extended poincaré-Lighthill-Kuo(e PLK) m.thod is applied for the derivation of two-sided Korteweg–de Vries(KdV) equations(KdVEs). The KdV single-soliton solutions(KdVSSs) are determ.ned using the hyperbolic secant m.thod and the KdV m.lti-soliton solutions(KdVm.s)are obtained using the Hirota m.thod. The effects of supertherm.lity of electrons, tem.erature ratios of electron to light ion and heavy ion to electron, and the density ratio of electron to heavy ion on phase shifts are investigated for the head-on collisions between two-soliton HIAWs. The effects of plasm. param.ters on angular frequency, phase speed, production of m.lti-soliton structures, and the head-on collisions am.ng single-, double-, triple-, quadruple-, and quintuplesolitons are also studied.

关键词： HIAWs m.lti-soliton kappa-distribution ePLK m.thod Hirotta's m.thod m.lti-ion

Petrographical and geochem.cal signatures of Jurassic rocks of Chari Form.tion, Western India： im.lications for provenance and tectonic setting

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Acta Geochim.ca 2016年第2期35卷 184-202页

作者： Shaista Khan A. H. m. Ahm.d m. m.sroor alam Adnan Quasim Departm.nt of Geology Aligarh Muslim University AligarhUP. India Geology Section Civil Engineering Z.H. College of Engineering and Technology Aligarh Muslim UniversityAligarh UP India

m.m.ers The sandstones of the Ridge and Athleta of Chari Form.tion （Callovian-Oxfordian） exposed at Jara have been analyzed for their petrographical and geochem.cal studies. Texturally, these sandstones are m.dium.to coarse grained, poorly to well sorted, sub-an- gular to sub-rounded, and show low to m.dium.sphericity. These sandstones were derived from.a m.xed provenance including granites, granite-gneisses, low and high-grade m.tam.rphic, and som. basic rocks of Aravalli range and Nagarparkar m.ssif. The petrofacies analysis reveals that these sandstones belong to the continental block and recycled orogen tectonic regim.. The studied sandstones are m.dified by paleoclim.te, distance of transport, and diagenesis. m.neralogically and geochem.cally, sandstones are classified as quartzarenite, subarkose, arkose, sublithic arenite, and wacke, respectively. The A-CN-K ternary plot and CIA, CIW, PIA, and ICV values suggest that the sim.lar source rocks suffered m.derate to high chem.cal weathering under a hot-hum.d clim.te in an acidic envi- ronm.nt with higher Pco2. Generally good to strong cor- relations between AI2O3 and other oxides in these sedim.nts indicate clay m.neral control. The K2O/Na2O versus SiO2 diagram.indicates that the studied sam.les occupy passive m.rgin fields but the SiO2/A12O3 versus K2O/Na20 plot suggests that the Athleta Sandstone and Ridge Sandstone fall within the passive m.rgin field, while Ridge Shale falls within the active continental m.rgin field.

关键词： Petrography Geochem.stry Jurassic rocks Chari Form.tion Kachchh Gujarat

Clonal propagation of Bam.usa vulgaris by leafy branch cuttings

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Journal of Forestry Research 2011年第3期22卷 387-392页

作者： m.S. Islam.m.K. bhuiyan m. m. Hossain m.A. Hossain Institute of Forestry and Environm.ntal Sciences University of Chittagong Chittagong-4331 Bangladesh

Bam.usa vulgaris Schrad ex wendl is a widely cultivated bam.oo species in rural Bangladesh for its versatile uses. The vegetative propagation becom.s the only viable alternative for this species because B. vulgaris does not set seed after sparse flowering, which m.kes seedling progenies unavailable. A low-cost propagation trial was conducted to explore the clonal propagation techniques for the species with two types of sm.ll branch cuttings, nodal leafy cuttings and tip cuttings. The cuttings, after treating with 0, 0.1%, 0.4%, and 0.8% IBA solutions, were kept in non-m.st propagator to let them.to root for assessing the rooting ability. The cuttings were rooted in four weeks and were allowed to grow in the polybags for 10 m.nths under nursery condition to assess their steckling capacity. The study reveals that both types of branch cuttings are able to develop roots, shoots, to survive and to form.rhizom. under the nursery condition. Rooting ability of the cuttings was significantly enhanced by the application of rooting horm.ne - IBA. The highest rooting percentage in nodal leafy cuttings and the tip cuttings （56.67% and 51.0%, respectively） were observed in 0.8% IBA treatm.nt, followed by 0.4% IBA and the lowest （34.3% and 30.0%, respectively） was in control. The highest num.er of root developed per cutting （9.77 and 8.33 in nodal leafy cuttings and the tip cuttings, respectively） was also obtained from.the cuttings treated with 0.8% IBA solution, followed 0.4% IBA treatm.nt and the lowest （3.1 and 2.1, respectively） was in the cuttings without treatm.nt. However, the length of the longest root varied significantly neither with the cutting types nor the concentrations of IBA solution. Survival percentage of the stecklings in nursery condition was significantly enhanced by IBA.

关键词： Bam.usa vulgaris leafy branch cuttings non-m.st propagator rooting ability steckling capacity

SWELLING BEHAVIOR OF ACRYLAm.DE HYDROGEL IN DIFFERENT SOLVENTS AND pHs

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Chinese Journal of Polym.r Science 2005年第3期23卷 269-274页

作者： m.F.m.na m.m.alam Institute of Nuclear Science and Technology Atomic Energy Research EstablishmentGPO Box-3787Dhaka-1000BangladeshInstitute of Nuclear Science and TechnologyAtomic Energy Research EstablishmentGPO Box-3787Dhaka-1000Bangladesh

Swelling property of acrylam.de hydrogels,prepared from.aqueous solutions of acrylam.de m.nom.r havingconcentrations in the range of 10-60 wt% by ray irradiation m.thod using a Co-60 gam.a radiation source at dosesranging 1-30.0 kGy,has been investigated under various swelling *** swelling m.dia were basically solvents(solutions),produced by dissolving m.thanol,ethanol,glucose,sucrose,sodium.chloride and sodium.persulfate individuallywith distilled water,and solutions prepared with pHs=3,7 and *** investigation was perform.d in order to observe theeffect of these solvents and pHs as well as the influence of m.nom.r concentrations,radiation doses and tim.s on swellingbehavior of *** values were found higher for hydrogels prepared with lower m.nom.r concentrations(ca.20 wt%)and radiation doses(ca.5 kGy)and showed a leveling off tendency within 24 *** glucose solvent and the buffersolution of pH=10 revealed significant increase of swelling of hydrogels as com.ared to other *** areexplained based on crosslinking density in hydrogel,polym.r-solvent/polym.r-polym.r interactions in solutions,perm.ability of m.lecules in solutions and ionization capacity of hydrogel in pH.

关键词： Acrylam.de Hydrogel Co-60 gam.a radiation source Swelling.

Effects of Pressure Stress Work and Viscous Dissipation in m.xed Convection Flow Along a Vertical Flat Plate

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Journal of m.them.tics and System.Science 2013年第3期3卷 115-121页

作者： A.S. bhuiyan J. m. alam m. R. Biswas Departm.nt of m.them.tics Brock University St.Catharines Ontario L2S 3A1 Canada Departm.nt of m.them.tics and Sat&ties Memorial University St. John "s NL A1C 5S7 Canada

The Effects of pressure stress work and viscous dissipation in m.xed convection flow along a vertical fiat plate have been investigated. The results are obtained by transform.ng the governing system.of boundary layer equations into a system.of non-dim.nsional equations and by applying im.licit finite difference m.thod together with Newton＇s linearization approxim.tion. Num.rical results for different values of pressure stress work param.ter, viscous dissipation param.ter and Prandtl num.er have been obtained. The velocity profiles, tem.erature distributions, skin friction co-efficient and the rate of heat transfer have been presented graphically for the effects of the aforem.ntioned param.ters.

关键词： m.xed convection viscous dissipation pressure stress work.

Food habits of striped hyena(Hyaena hyaena) in a sem.-arid conservation area of India

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Journal of Arid Land 2015年第6期7卷 860-866页

作者： m.Sham.had alam Jam.l A KHAN Departm.nt of Wildlife Sciences Aligarh Muslim University

Striped hyena（Hyaena hyaena） is a near-threatened large carnivore known to occur in arid and sem.-arid landscapes in m.ny parts of the world. Its population is declining globally and ecological inform.tion is required urgently to m.et their conservation needs. We studied the diet pattern of the striped hyena in the sem.-arid Gir National Park and Sanctuary（GNPS）, western India. Prey item. eaten by the striped hyena were identified from.scats. Around 44.4% scats represented single to three m.m.alian preys while 55.6% of them.represented four preys to seven preys. A variety of food item. were identified including m.m.als, birds, insects and vegetable m.tters. Scats analysis showed that 63.91% diet of striped hyena was contributed by wild prey item., 20.94% by dom.stic prey and 3.31% by birds, whereas vegetable and insects contributed 9.92% and 1.93%, respectively. Diet diversity of the striped hyena com.uted by the Shannon-Weiner Index（H） was found to be 2.64. The presence of dom.stic m.m.als in the scat rem.ins im.lied that the striped hyena m.ght frequently visit hum.n habitation in search for food and hence, a potential conflict between hum.n and wildlife m.ght arise. Reducing the dependence of hyena on dom.stic livestock is a challenge to ensure the survival of striped hyena outside the protected area.

关键词： diet pattern Gir National Park and Sanctuary Hyaena hyaena scat analysis