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Hydrogenic Donor in a Spherical Quantum Dot with Different Confinements

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Chinese Physics Letters 2009年第8期26卷 309-312页

作者： A. John Peter K. Navaneethakrishnan govt. Arts College Melur-625 106 Madurad India Madurai Kamaraj-University Madurai-625 021 India

Binding energies of a hydrogenic donor in a spherical GaAs quantum dot surrounded by Ga1-xA4xAs matrix are calculated. The results are presented for realistie barrier heights corresponding to different values of x （x 〈 0.4）. The calculations are performed under two different conditions：（i） a spherical dot with square well confinement and （ii） a dot with parabolic potential well confinement. The results show that （i） the donor ionization energies are always higher under parabolic confinement as compared to a dot of the same radius under square well confinement and （ii） the oscillator strengths coupling ground state with excited states are two orders larger under parabolic confinement. Our results are in agreement with the results of other researchers.

关键词： ELECTRON donor-acceptor complexes QUANTUM dots BINDING energy OSCILLATOR strengths PLASMA confinement QUANTUM wells GALLIUM arsenide semiconductors

A review of jellyfish aggregations, focusing on india’s coastal waters

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Ecological Processes 2020年第1期9卷 689-697页

作者： Sanjiba Kumar Baliarsingh Aneesh Anandrao Lotliker Suchismita Srichandan Alakes Samanta Nimit Kumar T.M.Balakrishnan Nair indian National Centre for Ocean Information Services Ministry of Earth SciencesGovt.of IndiaHyderabad 500090India

A review of jellyfish aggregations focused on india’s coastal waters was conducted,with the aim to enhance understanding of conducive conditions and subsequent ecological *** swarming,as well as their beach strandings,have been reported from many areas of the world—including india’s coastal waters.A variety of natural(winds,tidal fronts,surface currents,water temperature,salinity,turbidity,dissolved oxygen)and anthropogenic(water quality deterioration,overfishing,translocation,habitat modification)factors play pivotal roles in triggering jellyfish *** aggregation events in the forms of their swarming in coastal waters and beach strandings have resulted in ephemeral nuisances such as water quality deterioration,food chain alterations,hindrance in seawater uptake by power plants,clogging of nets during fishing operations,and tourism *** well-known indian tourist beaches(e.g.,Puri,Chennai,Goa,and Mumbai)have experienced beach *** recurrence of such events,jellyfishes are relatively less scientifically investigated and monitored in indian coastal ***,it is important to determine the environmental conditions that trigger jellyfish swarming,in order to develop effective monitoring and prediction *** study additionally proposes a conceptual framework towards development of a jellyfish monitoring system for indian waters using satellite and model data.

关键词： Jellyfish Swarming Coast Water quality Bay of Bengal Arabian Sea

Mineralogical and Geochemical Evidence of Fluid-rock Interaction at the Shallow Crustal Level in Koyna Seismogenic Region, Maharashtra, india: Impact and Implications

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Acta Geologica Sinica(English Edition) 2021年第S01期95卷 40-43页

作者： Halder PIYAL Kumar Shukla MATSYENDRA Kumar KAMLESH Sharma ANUPAM Birbal Sahni Institute of Palaeosciences(DST Govt.of India)LucknowU.P.India govt.of india Ministry of Earth SciencesBorehole Geophysics Research LaboratoryKaradMaharashtraIndia

The Koyna region of Maharashtra located in the western part of the~65 Myr old Deccan traps province,overlying the Neoarchean cratonic granitoid basement of peninsular india,has been experiencing recurring seismicity s... 详细信息

关键词： Continental Deep Drilling Programme artificial reservoir triggered seismicity fluid-rock interaction shallow crustal level geophysical anomaly clay mineral hydrothermal alteration

Empirical model for fusion cross sections of Ca-induced reactions

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Chinese Physics C 2024年第3期48卷 126-132页

作者： Reddi Rani.L N.Sowmya K.N Sridhar H C.Manjunatha M.M.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical formula for the astrophysical S-factor has been suggested as a function of the Coulomb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)Ca as projectiles were considered for different targets,leading to compound nuclei with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfield factor,and the empirical formula for the *** study's findings showed better agreement with those of available experiments when compared to Wong's *** present work leads to a smaller standard deviation value than Wong's formula when used to correlate the experimental data of calcium-induced fusion ***'s formula provides a good approximation of fusion cross-sections when the center of mass energy is below the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formula Gamow-Sommerfield-factor Geometric-factor S-factor

Effects of Electric Field on Electronic States in a GaAs/GaAlAs Quantum Dot with Different Confinements

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Chinese Physics Letters 2008年第8期25卷 3021-3024页

作者： A. John Peter Vemuri Lakshminarayana govt. Arts College Melur-625 106 Madurai India Mohamed Sathak Engineering College Kilakarai-623 806 Rarnnad India

Binding energies of shallow hydrogenic impurity in a GaAs/GaAlAs quantum dot with spherical confinement, parabolic confinement and rectangular confinement are calculated as a function of dot radius in the influence of electric field. The binding energy is calculated following a variational procedure within the effective mass approximation along with the spatial depended dielectric function. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. It is found that the contribution of spatially dependent screening effects are small for a donor impurity and it is concluded that the rectangulax confinement is better than the parabolic and spherical confinements. These results are compared with the existing literature.

关键词： BINDING-ENERGY IMPURITY STATES HYDROGENIC IMPURITIES MAGNETIC-FIELDS DONOR STATES EXCITON GAAS-GA1-XALXAS CRYSTALLITES CLUSTERS GAAS

Non Existence of Shear in Bianchi Type-ⅢString Cosmological Models with Bulk Viscosity and Time-Dependent A Term

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Chinese Physics Letters 2011年第2期28卷 55-57页

作者： R.K.Tiwari Sonia Sharma Department of Mathematics Govt.Model Science CollegeRewa(MP)India Department of Mathematics Rayat Polytechnic CollegeRopar(Punjab)India

We study the non existence of shear in locally rotationally symmetric Bianchi type-Ⅲstring cosmological models with bulk viscosity and variable cosmological termΛ.Exact solutions of the field equations are obtained by assuming the conditions:the bulk viscosity is proportional to the expansion scalar,ξ∝θ,expansion scalar is proportional to shear scalar,θ∝σ,and A is proportional to the Hubble *** coefficient of bulk viscosity is assumed to be a power function of mass *** corresponding physical interpretations of the cosmological solutions are also discussed.

关键词： parameter density viscosity

LRS Bianchi Type-II Cosmological Model with a Decaying Lambda Term

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Chinese Physics Letters 2012年第1期29卷 35-37页

作者： R.K.Tiwari D.Tiwari Pratibha Shukla Department of Mathematics Govt.Model Science College RewaM.P.486001India

We consider a locally rotationally symmetric(LRS)Bianchi type-Ⅱspacetime with a perfect fluid and a variable cosmological constant∧.To solve the Einstein field equations we consider the cosmological term∧to be proportional to R^(-m) with R being the scale factor and m a constant[***.D 58(1998)043506].In this model we obtain∧~H^(2),∧~(R)/R and Larnbda~t^(-2),in agreement with the main dynamical laws for the decay of∧.The physical significance of the cosmological model is also discussed.

关键词： Bianchi Cosmo perfect

Spectroscopic investigations and luminescence spectra of Sm3+ doped soda lime silicate glasses

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Journal of Rare Earths 2009年第5期27卷 773-780页

作者： Y.K. Sharma S.S.L. Surana R.K. Singh Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India Department of Physics J. N. V. University Jodhpur-342001 India Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India

Sm3+ doped soda lime silicate glasses co-doped with As2O3 were prepared and characterised by measuring their absorption spectra in UV-VIS/NIR regions and luminescence spectra in the visible region. Judd-Ofelt intensity parameters, Ωλ, were evaluated from the measured intensities of the various absorption bands. Ωλ parameters of these glasses were compared with the Ωλ parameters of other reported Sm3+ glasses to study the bonding environment surrounding the Sm3+ in the present glasses. Presence of [AsO4]3– tetrahedra in the second coordination sphere around the central Sm3+ ion made these glasses less covalent as compared to other oxide glasses but the ratio Ω4/Ω6 of the 1.83 indicated them to be fairly stable. With the help of Ωλ parameters and luminescence data for various emission lines, radiative properties for different emission lines were calculated. The values of radiative properties indicated that 4G5/2→6H7/2 and 4G5/2→6H9/2 transitions responsible for orange luminescence might be used in the development of materials for LED's and other optical devices in the visible region.

关键词： rare earth glasses Judd-Ofelt theory absorption spectroscopy luminescence

Energy Efficient Load Balancing and Routing Using Multi-Objective Based Algorithm in WSN

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Intelligent Automation & Soft Computing 2023年第3期35卷 3227-3239页

作者： Hemant Kumar Vijayvergia Uma Shankar Modani Department of Electronics&Communication Engineering Govt.Mahila Engineering CollegeAjmerRajasthanIndia Department of Electronics&Communication Engineering Govt.Engineering CollegeAjmerIndia

In wireless sensor network(WSN),the gateways which are placed far away from the base station(BS)forward the collected data to the BS through the gateways which are nearer to the *** leads to more energy consumption because the gateways nearer to the BS manages heavy trafﬁc ***,to over-come this issue,loads around the gateways are to be balanced by presenting energy efﬁcient clustering ***,to enhance the lifetime of the net-work,optimal routing path is to be established between the source node and *** energy efﬁcient load balancing and routing,multi objective based beetle swarm optimization(BSO)algorithm is presented in this *** this algo-rithm,optimal clustering and routing are performed depend on the objective func-tions routingﬁtness and clusteringﬁ*** approach leads to decrease the power *** results show that the performance of the pro-posed BSO based clustering and routing scheme attains better results than that of the existing algorithms in terms of energy consumption,delivery ratio,through-put and network ***,the proposed scheme increases throughput to 72%and network lifetime to 37%as well as it reduces delay to 37%than the existing optimization algorithms based clustering and routing schemes.

关键词： Wireless sensor network(WSN) load balancing clustering routing beetle swarm optimization(BSO)