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Wyszukujesz frazę "Singh, S. B." wg kryterium: Autor

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    Wyświetlanie 1-29 z 29
    Tytuł:
    Asymptotic approximations to the non-isothermal distributed activation energy model for bio-mass pyrolysis
    Autorzy:
    Dhaundiyal, A.
    Singh, S. B.
    Powiązania:
    https://bibliotekanauki.pl/articles/386522.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    biomass pyrolysis
    distributed activation energy model (DAEM)
    DAEM
    non-isothermal kinetics
    gamma distribution
    asymptotic expansion
    erlang distribution
    Opis:
    This paper describes the influence of some parameters significant to biomass pyrolysis on the numerical solutions of the non-isothermal nth order distributed activation energy model (DAEM) using the Gamma distribution and discusses the special case for the positive integer value of the scale parameter (), i.e. the Erlang distribution. Investigated parameters are the integral upper limit, the frequency factor, the heating rate, the reaction order, and the shape and rate parameters of the Gamma distribution. Influence of these parameters has been considered for the determination of the kinetic parameters of the non-isothermal nth order Gamma distribution from the experimentally derived thermoanalytical data of biomass pyrolysis. Mathematically, the effect of parameters on numerical solution is also used for predicting the behaviour of the unpyrolysized fraction of biomass with respect to temperature. Analysis of the mathematical model is based upon asymptotic expansions, which leads to the systematic methods for efficient way to determine the accurate approximations. The proposed method, therefore, provides a rapid and highly effective way for estimating the kinetic parameters and the distribution of activation energies.
    Źródło:
    Acta Mechanica et Automatica; 2017, 11, 4; 293-301
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal creep stress and strain analysis in a non-homogeneous spherical shell
    Autorzy:
    Thakur, P.
    Singh, S. B.
    Pathania, D. S.
    Verma, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/949332.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
    Tematy:
    stress
    strain rates
    thermal
    spherical shell
    non-homogeneous
    Opis:
    The purpose of this paper is to present study of thermal creep stress and strain rates in a non-homogeneous spherical shell by using Seth’s transition theory. Seth’s transition theory is applied to the problem of creep stresses and strain rates in the non-homogeneous spherical shell under steady-state temperature. Neither the yield criterion nor the associated flow rule is assumed here. With the introduction of thermal effect, values of circumferential stress decrease at the external surface as well as internal surface of the spherical shell. It means that the temperature dependent materials minimize the possibility of fracture at the internal surface of the spherical shell. The model proposed in this paper is used commonly as a design of chemical and oil plants, industrial gases and stream turbines, high speed structures involving aerodynamic heating.
    Źródło:
    Journal of Theoretical and Applied Mechanics; 2017, 55, 4; 1155-1165
    1429-2955
    Pojawia się w:
    Journal of Theoretical and Applied Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Reflection of plane waves from a free surface of a generalized magneto-thermoelastic solid half-space with diffusion
    Autorzy:
    Singh, B.
    Singh, L.
    Deswal, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/282051.pdf
    Data publikacji:
    2014
    Wydawca:
    Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
    Tematy:
    generalized thermoelasticity
    plane waves
    reflection
    magnetic field
    diffusion
    Opis:
    Green-Naghdi’s theory of generalized thermoelasticity is applied to study the reflection of P and SV waves from the free surface of a magneto-thermoelastic solid half-space. The boundary conditions are satisfied by appropriate potential functions to obtain a system of four non-homogeneous equations in reflection coefficients. The reflection coefficients depend upon the angle of incidence of P and SV waves, magnetic field, thermal field, diffusion parameters and other material constants. The numerical values of the modulus of the reflection coefficients are shown graphically with the angle of incidence of P and SV waves. The effect of magnetic field is observed significantly on various reflected waves.
    Źródło:
    Journal of Theoretical and Applied Mechanics; 2014, 52, 2; 385-394
    1429-2955
    Pojawia się w:
    Journal of Theoretical and Applied Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    On propagation of Rayleigh type surface wave in five different theories of thermoelasticity
    Autorzy:
    Singh, B.
    Verma, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/265155.pdf
    Data publikacji:
    2019
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    termoelastyczność
    fala powierzchniowa
    fala Rayleigha
    równanie częstotliwości
    generalized thermoelasticity
    surface waves
    Rayleigh wave
    frequency equation
    Opis:
    The governing equations for a homogeneous and isotropic thermoelastic medium are formulated in the context of coupled thermoelasticity, Lord and Shulman theory of generalized thermoelasticity with one relaxation time, Green and Lindsay theory of generalized thermoelasticity with two relaxation times, Green and Nagdhi theory of thermoelasticity without energy dissipation and Chandrasekharaiah and Tzou theory of thermoelasticity. These governing equations are solved to obtain general surface wave solutions. The particular solutions in a halfspace are obtained with the help of appropriate radiation conditions. The two types of boundaries at athe surface of a half-space are considered namely, the stress free thermally insulated boundary and stress free isothermal boundary. The particular solutions obtained in a half-space satisfy the relevant boundary conditions at the free surface of the half-space and a frequency equation for the Rayleigh wave speed is obtained for both thermally insulated and isothermal cases. The non-dimensional Rayleigh wave speed is computed for aluminium metal to observe the effects of frequency, thermal relaxation time and different theories of thermoelasticity.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2019, 24, 3; 661-673
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    On Rayleigh wave in generalized magneto-thermoelastic media with hydrostatic initial stress
    Autorzy:
    Singh, B.
    Kumari, S.
    Singh, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/201293.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    generalized thermoelasticity
    hydrostatic initial stress
    magnetic field
    Rayleigh wave
    frequency equation
    Opis:
    The governing equations of generalized magneto-thermoelasticity with hydrostatic initial stress are solved for surface wave solutions. The particular solutions in the half-space are applied to the boundary conditions at the free surface of the half-space to obtain the frequency equation of Rayleigh wave. The frequency equation is approximated for small thermal coupling and small reduced frequency. The velocity of propagation and amplitude-attenuation factor of Rayleigh wave are computed numerically for a particular material. Effects of magnetic field and hydrostatic initial stress on the velocity of the propagation and amplitude-attenuation factor are shown graphically.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 2; 349-352
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A collaborative strategy for a three echelon supply chain with ramp type demand, deterioration and inflation
    Autorzy:
    Singh, N.
    Vaish, B.
    Singh, S. R.
    Powiązania:
    https://bibliotekanauki.pl/articles/406653.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    three echelon supply chain
    ramp type demand
    deterioration
    backlogging
    inflation
    Opis:
    A supply chain system has been investigated in which a single manufacturer procures raw materials from a single supplier, processes them to produce finished products, and then delivers the products to a single retailer. The customer’s demand rate is assumed to be time-sensitive in nature (ramp type) that allows two-phase variation in the demand and production rate. Our adoption of ramp type demand reflects a real market demand for a newly launched product. Shortages are allowed with partial backlogging of demand (only for the retailer), i.e. the rest represent lost sales. The effects of inflation of the cost parameters and deterioration are also considered separately. We show that the total cost function is convex. Using this convexity, a simple algorithm is presented to determine the optimal order quantity and optimal cycle time for the total cost function. The results are discussed with numerical examples and particular cases of the model discussed briefly. A sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out.
    Źródło:
    Operations Research and Decisions; 2014, 24, 3; 78-100
    2081-8858
    2391-6060
    Pojawia się w:
    Operations Research and Decisions
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Genetic variability, inheritance and correlation for mineral contents in cabbage (Brassica oleracea var. capitata L.)
    Autorzy:
    Singh, B.K.
    Sharma, S.R.
    Singh, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/2100.pdf
    Data publikacji:
    2013
    Wydawca:
    Instytut Ogrodnictwa
    Tematy:
    cabbage
    Brassica oleracea var.capitata
    genetic variability
    inheritance
    mineral content
    dietary mineral
    iron
    zinc
    copper
    manganese
    potassium
    calcium
    heritability
    Źródło:
    Journal of Horticultural Research; 2013, 21, 1
    2300-5009
    Pojawia się w:
    Journal of Horticultural Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A three level integrated inventory model with time dependent demand and production rate under a trade credit policy for both distributor and retailer
    Autorzy:
    Singh, N.
    Vaish, B.
    Singh, S. R.
    Powiązania:
    https://bibliotekanauki.pl/articles/206192.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Instytut Badań Systemowych PAN
    Tematy:
    time dependent demand
    variable production rate
    three echelon supply chain
    trade credit
    Opis:
    This paper develops a three echelon supply chain inventory model with permissible delay in payment, in which distributor and retailer’s demand is time dependent and production rate for manufacturer is also time sensitive. The models consider the two level trade credit policy in manufacturer-distributor and distributor-retailer relationship in this supply chain model. A simple solution algorithm is presented to determine the optimal order quantity and optimal cycle time of the total cost function and the number of shipments for distributor and retailer. The results are discussed with numerical examples and the particular cases of the model are also discussed in brief.
    Źródło:
    Control and Cybernetics; 2014, 43, 3; 439-469
    0324-8569
    Pojawia się w:
    Control and Cybernetics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Class of Chain Ratio-Cum-Dual to Ratio Type Estimator with Two Auxiliary Characters Under Double Sampling in Sample Surveys
    Autorzy:
    Choudhury, S.
    Singh, B. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/465944.pdf
    Data publikacji:
    2012
    Wydawca:
    Główny Urząd Statystyczny
    Tematy:
    auxiliary variate
    double sampling
    chain ratio-cum-dual to ratio estimator
    bias
    variance
    efficiency
    Opis:
    This paper considers a chain ratio-cum-dual to ratio type estimator for estimating population mean of the study variate using two auxiliary variates under double (two-phase) sampling procedure, when the information on another additional auxiliary variate is available along with the main auxiliary variate. The asymptotically optimum estimators (AOEs) in the class are identified in two different cases with their bias and variances. The optimum values of the first phase and second phase sample sizes have been obtained for the fixed cost of survey. Theoretical and empirical studies have also been done to demonstrate the efficiency of the proposed estimator with respect to strategies which utilized the information on two auxiliary variates.
    Źródło:
    Statistics in Transition new series; 2012, 13, 3; 519-536
    1234-7655
    Pojawia się w:
    Statistics in Transition new series
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Stability analysis and internal heating effect on oscillatory convection in a viscoelastic fluid saturated porous medium under gravity modulation
    Autorzy:
    Bhadauria, B. S.
    Singh, M. K.
    Singh, A.
    Singh, B. K.
    Kiran, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/265014.pdf
    Data publikacji:
    2016
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    analiza stabilności
    grawitacja
    ciecz lepkosprężysta
    nonlinear stability analysis
    complex Ginzburg-Landau equation
    gravity modulation
    internal heating
    bifurcation
    Opis:
    In this paper, we investigate the combined effect of internal heating and time periodic gravity modulation in a viscoelastic fluid saturated porous medium by reducing the problem into a complex non-autonomous Ginzgburg-Landau equation. Weak nonlinear stability analysis has been performed by using power series expansion in terms of the amplitude of gravity modulation, which is assumed to be small. The Nusselt number is obtained in terms of the amplitude for oscillatory mode of convection. The influence of viscoelastic parameters on heat transfer has been discussed. Gravity modulation is found to have a destabilizing effect at low frequencies and a stabilizing effect at high frequencies. Finally, it is found that overstability advances the onset of convection, more with internal heating. The conditions for which the complex Ginzgburg-Landau equation undergoes Hopf bifurcation and the amplitude equation undergoes supercritical pitchfork bifurcation are studied.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2016, 21, 4; 785-803
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chaotic convection of viscoelastic fluid in porous medium under G-jitter
    Autorzy:
    Bhadauria, B. S.
    Singh, A.
    Singh, M. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/265559.pdf
    Data publikacji:
    2019
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    teoria nieliniowa
    grawitacja
    konwekcja
    non-linear theory
    gravity modulation
    chaotic convection
    Opis:
    The present article aims at investigating the effect of gravity modulation on chaotic convection of a viscoelastic fluid in porous media. For this, the problem is reduced into Lorenz system (non-autonomous) by employing the truncated Galerkin expansion method. The system shows transitions from periodic to chaotic behavior on increasing the scaled Rayleigh number R. The amplitude of modulation advances the chaotic nature in the system while the frequency of modulation has a tendency to delay the chaotic behavior which is in good agreement with the results due to [1]. The behavior of the scaled relaxation and retardation parameter on the system is also studied. The phase portrait and time domain diagrams of the Lorenz system for suitable parameter values have been used to analyze the system.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2019, 24, 1; 37-51
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Performance Comparison of Protection Strategies in WDM Mesh Networks
    Autorzy:
    Singh, H. K.
    Aggarwal, S.
    Singh, S.
    Mohapatra, B.
    Nagaria, R. K.
    Tiwari, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/308073.pdf
    Data publikacji:
    2010
    Wydawca:
    Instytut Łączności - Państwowy Instytut Badawczy
    Tematy:
    blocking probability
    protection
    survivability
    switching time
    WDM networks
    Opis:
    Recent development in optical networking employing wavelength division multiplexing (WDM) fulfills the high bandwidth demand applications. Failure of such networks, leads to enormous data and revenue loss. Protection is one of the key techniques, which is used in designing survivable WDM networks. In this paper we compare dedicated and shared protection strategies employed inWDMmesh networks to protect optical networks failure, particularly fiber failure. Dijkstra's shortest path algorithm is considered for carrying out simulations. The paper compares the performance of protection schemes, such as, dedicated path protection (DPP), shared path protection (SPP) and shared link protection (SLP) schemes. Capacity utilization, switching time and blocking probability are the parameters considered to measure the performance of the protection schemes. Simulation results show that, SPP is more efficient in terms of capacity utilization over DPP and SLP schemes, whereas, SLP offered better switching time than both DPP and SPP schemes. The average call drop rate is minimum for shared path protection scheme and maximum for shared link protection scheme.
    Źródło:
    Journal of Telecommunications and Information Technology; 2010, 1; 62-69
    1509-4553
    1899-8852
    Pojawia się w:
    Journal of Telecommunications and Information Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal convection of magneto compressible couple-stress fluid saturated in a porous medium with Hall current
    Autorzy:
    Mehta, C. B.
    Singh, M.
    Kumar, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/265186.pdf
    Data publikacji:
    2016
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    pole magnetyczne
    ściśliwość
    porowatość
    prądy Hall'a
    couple stress fluids
    horizontal magnetic field
    compressibility
    porous medium
    Hall currents
    Opis:
    An investigation is made on the effect of Hall currents on thermal instability of a compressible couple-stress fluid in the presence of a horizontal magnetic field saturated in a porous medium. The analysis is carried out within the framework of the linear stability theory and normal mode technique. A dispersion relation governing the effects of viscoelasticity, Hall currents, compressibility, magnetic field and porous medium is derived. For the stationary convection a couple-stress fluid behaves like an ordinary Newtonian fluid due to the vanishing of the viscoelastic parameter. Compressibility, the magnetic filed and couple-stress parameter have stabilizing effects on the system whereas Hall currents and medium permeability have a destabilizing effect on the system, but in the absence of Hall current couple-stress has a destabilizing effect on the system. It has been observed that oscillatory modes are introduced due to the presence of viscoelasticity, magnetic field porous medium and Hall currents which were non-existent in their absence.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2016, 21, 1; 83-93
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Homology modeling deduced tridimensional structure of Bacillus thuringiensis Cry1Ab18 toxin
    Autorzy:
    Kashyap, S.
    Singh, B.D.
    Amla, D.V.
    Powiązania:
    https://bibliotekanauki.pl/articles/79996.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    three-dimensional structure
    homology modelling
    Bacillus thuringiensis
    soil bacteria
    Cry1Ab18 toxin
    delta-endotoxin
    3D modelling
    transgenic crop
    biopesticide
    Źródło:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2012, 93, 1
    0860-7796
    Pojawia się w:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of organic inputs on strength and stability of soil aggregates under rice-wheat rotation
    Autorzy:
    Das, B.
    Chakraborty, D.
    Singh, V.K.
    Aggarwal, P.
    Singh, R.
    Dwivedi, B.S.
    Powiązania:
    https://bibliotekanauki.pl/articles/25472.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    tensile strength
    stability
    soil aggregate
    rice
    wheat
    cereal crop rotation
    Opis:
    The study aims to elucidate the impact of organic inputs on strength and structural stability of aggregates in a sandy loam soil. Tensile strength, friability and water stability of aggregates, and the carbon contents in bulk soil and in large macro (>2 mm), small macro (0.25-2 mm), micro (0.053-0.25 mm) and silt+clay size (<0.053) aggregates were evaluated in soils from a long-term experiment with rice-wheat rotation at Modipuram, India, with different sources and amounts of organic C inputs as partial substitution of N fertilizer. Addition of organic substrates significantly improved soil organic C contents, but the type and source of inputs had different impacts. Tensile strength of aggregates decreased and friability increased through organic inputs, with a maximum effect under green gram residue (rice)-farmyard manure (wheat) substitution. Higher macroaggregates in the crop residue- and farmyard manure-treated soils resulted in a higher aggregate mean weight diameter, which also had higher soil organic C contents. The bulk soil organic C had a strong relation with the mean weight diameter of aggregates, but the soil organic C content in all aggregate fractions was not necessarily effective for aggregate stability. The soil organic C content in large macroaggregates (2-8 mm) had a significant positive effect on aggregate stability, although a reverse effect was observed for aggregates <0.25 mm. Partial substitution of nitrogen by organic substrates improved aggregate properties and the soil organic C content in bulk soil and aggregate fractions, although the relative effect varied with the source and amount of the organic inputs.
    Źródło:
    International Agrophysics; 2014, 28, 2
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modelling and Experimental Characterization of Processing Parameters in Vertical Twin Roll Casting of Aluminium Alloy A356
    Autorzy:
    Dhindaw, B.
    Singh, S.
    Mandal, A.
    Pandey, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1840923.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    alloy A356
    structural materials
    microstructures
    vertical twin-roll casting
    roll speeds
    numerical modelling
    stop A356
    mikrostruktura
    odlewanie dwuwalcowe
    prędkości rolek
    modelowanie numeryczne
    Opis:
    Production of near net shape thin strips using vertical twin roll casting method has been studied. In a typical VTRC process, the simultaneous action of solidification and rolling makes the process quite attractive as well as complicated. An industrially popular alloy A356 has been chosen for the VTRC processing. It is challenging to identify VTRC processing parameters for the alloy to produce thin strips because of its freezing range and complex composition. In the present work processing parameters of VTRC like roll speed, roll gap, melt superheat and the interface convective heat transfer coefficient have been investigated through modelling of the process. The mathematical model was developed which simultaneously solves the heat transfer, fluid flow and solidification, using commercial software COMSOL Multiphysics 5.4. VTRC sheets of alloy A356 were produced in an experimental set up and attempts were made to correlate the microstructures of VTRC A356 alloy to that predicted from the numerical studies to validate the model.
    Źródło:
    Archives of Foundry Engineering; 2020, 20, 4; 121-132
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of Potassium Perchlorate as a Burning Rate Modifier in Composite Propellant Formulations
    Autorzy:
    Jain, S.
    Mehilal, D.
    Singh, P. P.
    Bhattacharya, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/358405.pdf
    Data publikacji:
    2016
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    composite propellant
    burning rate
    ammonium perchlorate
    potassium perchlorate
    Opis:
    The burning rate of a solid composite propellant is one of its most important ballistic properties. To achieve a specified burning rate, transition metal oxides are used as burning rate modifiers. However, addition of transition metal oxides creates inertness in the composition. To avoid such inertness, an attempt has been made to incorporate potassium perchlorate (KP) as a burning rate modifier by partially replacing ammonium perchlorate (AP), up to the 10% level, and the composition was then studied in detail for its mechanical, thermal and ballistic properties. The data revealed that no change occurred in the case of the mechanical properties, however, the thermal stability decreased as the KP content was increased. The burning rate data revealed that on incorporation of 10% KP, there was an enhancement in the burning rate of up to 35% in comparison to the original composite propellant formulation, but beyond this no enhancement in burning rate was observed, indicating that the optimum content for KP in the composition had been reached.
    Źródło:
    Central European Journal of Energetic Materials; 2016, 13, 1; 231-245
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Intranasal (IN) COVID-19 vaccines - a breakthrough
    Autorzy:
    Gambhir, R.S.
    Kaur, K.
    Matariya, R.
    Singh, B.
    Sood, R.
    Singh, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/28765534.pdf
    Data publikacji:
    2023
    Wydawca:
    Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
    Opis:
    Emerging variants of COVID-19 have threatened the effectiveness of intramuscular (IM) vaccines since that are made to target only the spike protein. Development of Intranasal (IN) vaccination has been proven to provide both the mucosal and systemic immune responses for broader and long lasting protection. Many IN vaccine candidates (virus-vectored vaccines, recombinant subunit vaccines and live attenuated vaccines) are in different phases of clinical trials and in near future many companies would be releasing their vaccines into the drug market. Potential advantages of IN vaccination over IM vaccination makes them ideal to be administered in children and developing populations of the world. This paper focuses on the very recent developments in intranasal vaccination with a spotlight on their safety and efficacy concerns. IN vaccination can prove to be game-changer in handling COVID-19 and potential viral contagious diseases in future.
    Źródło:
    Roczniki Państwowego Zakładu Higieny; 2023, 74, 1; 15-18
    0035-7715
    Pojawia się w:
    Roczniki Państwowego Zakładu Higieny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of van Hove Singularity on T$\text{}_{c}$ in Rb doped C$\text{}_{60}$
    Autorzy:
    Agrawal, B. K.
    Agrawal, S.
    Yadav, P. S.
    Srivastava, P.
    Srivastava, R.
    Singh, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/2035748.pdf
    Data publikacji:
    2003-05
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    74.25.Jb
    74.62.Fj
    74.70.Wz
    Opis:
    In the present study we investigate the role of van Hove singularity on the optimization of T$\text{}_{c}$ in Rb doped fullerenes C$\text{}_{60}$ Rb$\text{}_{3}$. A first principles self-consistent full potential linear muffin-tin orbital method using density functional theory in local density approximation was employed. The doped Rb atoms are of two types occupying the tetrahedral and interstitial positions in the fcc lattice. The added Rb atoms fill the t$\text{}_{1u}$ band of the undoped fullerenes C$\text{}_{60}$ up to half which makes C$\text{}_{60}$Rb$\text{}_{3}$ conducting. Saddle points leading to van Hove singularities are observed in the neighbourhood of the symmetry point L. The shifting of the van Hove singularity with the volume of the lattice is investigated. We observe a saddle point just at the Fermi level for a lattice constant of 14.435Å. The highest value of T$\text{}_{c}$ should thus be observed at the above lattice constant. This result is in excellent agreement with the observed high value of T$\text{}_{c}$ measured in C$\text{}_{60}$Rb$\text{}_{3}$ for a lattice constant of 14.435Å.
    Źródło:
    Acta Physica Polonica A; 2003, 103, 5; 477-482
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Covid-19 update: Omicron variant − a new emerging threat
    Autorzy:
    Mehta, S.
    Gambhir, R.S.
    Singh, B.
    Goel, R.
    Ghuman, K.S.
    Aggarwal, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/2083083.pdf
    Data publikacji:
    2022
    Wydawca:
    Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
    Tematy:
    COVID-19
    SARS-CoV-2 pandemic
    Omicron variant
    vaccine
    coronavirus pandemic
    Opis:
    A new health threat in the form of a new variant of Covid-19 called Omicron has emerged globally in this holiday season. This new variant has been declared a variant of concern (VOC) by the World Health Organization and experts are expecting another wave of the pandemic. A lot still unknown about this variant and researchers worldwide are conducting studies to find the nature and characteristics of this mutated strain. Cases have begun to rise dramatically around the world and many countries have already imposed travel restrictions again to prevent disease transmission. It is being speculated that this particular variant has got tendency of immune escape and therefore can even infect fully vaccinated individuals. Vaccination and adhering to Covid-19 guidelines and protocols can curtail the spread of the virus. The present paper focuses on what is currently known about this variant, antigen diagnostic tests, importance of getting fully vaccinated and having booster dose etc. If we want to emerge from this pandemic, countries should practice vaccine equality and solidarity for the good of mankind.
    Źródło:
    Roczniki Państwowego Zakładu Higieny; 2022, 73, 1; 13-16
    0035-7715
    Pojawia się w:
    Roczniki Państwowego Zakładu Higieny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of flux composition on the percentage elongation and tensile strength of welds in submerged arc welding
    Efekt składu topnika na wydłużenie procentowe i wytrzymałość na rozciąganie spawów przy spawaniu łukiem krytym
    Autorzy:
    Singh, B.
    Khan, Z. A.
    Siddiquee, A. N.
    Maheswari, S.
    Sharma, S. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/140322.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ultimate tensile strength
    carbon equivalent
    basicity index
    elements transfer
    delta quantity
    UTS
    wytrzymałość na rozciąganie
    równoważnik węglowy
    współczynnik zasadowości
    transfer pierwiastków
    wielkość delta
    Opis:
    This experimental study reveals the effects of CaF2, FeMn and NiO additions to the base fluxes on tensile strength and percentage elongation of the weld metal. The aim of this study is to develop suitable flux for mild steel for high tensile strength, impact strength and ductility. Bead on plate welds were made using submerged arc welding process. Mathematical model for percentage elongation and UTS of mild steel welds were made. The elements transfer to the welds have been correlated with the above mechanical performance characteristics. The effect of oxygen content on weld elongation and UTS also has been deduced. This study shows that CaF2 and NiO are the significant factors for tensile strength while FeMn is not significant for tensile strength. However, for elongation besides CaF2, the interaction of CaF2 and FeMn was also found significant. The effects of basicity index of the flux and carbon equivalent of the welds on tensile strength and percentage elongation of the welds have also been evaluated.
    W studium eksperymentalnym, przedstawionym w pracy, pokazano wpływ domieszek CaF2, FeMn i NiO do podstawowego składu topnika na wytrzymałość na rozciąganie i procentowe wydłużenie metalu spawu. Celem studium było opracowanie topnika odpowiedniego dla stali niskowęglowej, który zapewnia wysoką wytrzymałość na rozciąganie, wytrzymałość na udary i plastyczność. Ściegi spawów wykonano metodą spawania łukiem krytym. Opracowano model matematyczny wydłużenia procentowego i wytrzymałości na rozciąganie (UTS) dla spawów ze stali niskowęglowej. Zbadano korelację między wymienionymi charakterystykami mechanicznymi a transferem pierwiastków do spawu. Wyznaczono także wpływ zawartości tlenu na wydłużenie spawu i ostateczną wytrzymałość na rozciąganie. W badaniach doświadczalnych wykazano, że domieszki CaF2 oraz NiO są istotnymi czynnikami wpływającymi na wytrzymałość na rozciąganie, podczas gdy domieszka FeMn nie ma istotnego wpływu. Oceniono także wpływ współczynnika zasadowości topnika i równoważnika węglowego spawu na wydłużenie procentowe spawu.
    Źródło:
    Archive of Mechanical Engineering; 2016, LXIII, 3; 337-354
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Plant community characteristics and soil status in different land use systems in Dimapur district, Nagaland, India
    Autorzy:
    Singh, S.K.
    Kumar, K.W.
    Aier, B.
    Kanduri, V.P.
    Ahirwar, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/45630.pdf
    Data publikacji:
    2012
    Wydawca:
    Instytut Badawczy Leśnictwa
    Źródło:
    Leśne Prace Badawcze; 2012, 73, 4
    1732-9442
    2082-8926
    Pojawia się w:
    Leśne Prace Badawcze
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optimization of Ammonium Sulfamate Nitration for the Preparation of Ammonium Dinitramide
    Autorzy:
    Mandal, A. K.
    Kunjir, G. M.
    Singh, J.
    Adhav, S. S.
    Singh, S. K.
    Pandey, R. K.
    Bhattacharya, B.
    Lakshmi Kantam, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/358022.pdf
    Data publikacji:
    2014
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Opis:
    The reaction kinetics for the preparation of ammonium dinitramide (ADN) is described. ADN is the ammonium salt of the dinitramide anion, and belongs to the group of inorganic oxidizers, mainly useful for energetic rocket propellant formulations, particularly for underwater applications. It is also a potential candidate to replace ammonium perchlorate (AP), in order to develop chlorine-free, green propellants. At HEMRL, ADN is prepared by the nitration of ammonium sulfamate (AS) using mixed acid, followed by hydrolysis, neutralization with ammonia (g) and rectification using solvent. The nitration of ammonium sulfamate (AS) is carried out at a subzero temperature of -40 ±1 °C. The yield of ADN is reliant on the formation of dinitramidic acid, an intermediate product formed during the hydrolysis step, and its stability is predominantly dependent upon the level of acidity and temperature of the reaction medium. Prior to these kinetics studies, process optimization of the nitration of ammonium sulfamate (AS) was performed and gave the final mole ratio of AS:HNO3:H2SO4. Since the nitration of AS is sensitive to temperature, the rate of reaction was studied at fixed temperatures with variation of time, keeping all of the other parameters, such as vessel volume, agitator speed, feed rate etc., constant. During these studies, predetermined quantities of ammonium sulfamate (AS) and mixed acid were allowed to react at a fixed temperature (-40 ±1 °C) for different reaction periods to generate the concentration profile of AS. Using this concentration profile, the reaction order and reaction rate constant were evaluated. In order to find the effect of temperature on the reaction rate and yield, experiments were conducted at other temperatures such as -30 and -50 °C. In the present studies, it was found that the optimum temperature of nitration is -40 ±1 °C and that the rate of reaction follows a pseudo second order process with rate constant 0.01113 (min-1)•(mol/L)-1. The reaction time evaluated for 55 to 60% conversion is about 70-80 minutes at -40 ±1 °C, based on this kinetics. The activation energy of AS nitration was found to be -4.6 kcal/mol, using the reaction kinetic data based on the temperature dependent rate equation derived from Arrhenius’s law.
    Źródło:
    Central European Journal of Energetic Materials; 2014, 11, 1; 83-97
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Natural convection in a hydrodynamically and thermally anisotropic non-rectangular porous cavity: effect of internal heat generation/absorption
    Autorzy:
    Chandran, P.
    Sacheti, N. C.
    Bhadauria, B. S.
    Singh, A. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/264468.pdf
    Data publikacji:
    2018
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    konwekcja naturalna
    materiały porowate
    przepuszczalność
    dyfuzyjność cieplna
    źródło ciepła
    natural convection
    trapezoidal cavity
    porous medium
    permeability
    thermal diffusivity
    Darcy's law
    heat source/sink
    Opis:
    Laminar natural convection in a trapezoidal porous vertical cavity has been investigated in this work. It is assumed that the porous enclosure is filled up with a permeable material subject to hydrodynamic and thermal anisotropy, the flow being governed by the Darcy law as applicable to a non-isotropic medium. It is further assumed that (i) there is heating at the left vertical wall and cooling at the right wall of the enclosure and (ii) the flow domain is subject to the presence of heat source or heat sink. The partial differential equations governing the resulting free convection have been solved numerically in the non-dimensional forms. There arises a number of parameters relating to buoyancy, internal heating, cavity aspect ratio and inclination of the upper surface to the horizontal. The influence of these parameters has been illustrated and analyzed through contours of streamlines and isotherms. We have also discussed the role of internal heating as well as anisotropy on the heat transfer characteristics.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2018, 23, 3; 595-609
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Stability analysis of a shallow depth metro tunnel: a numerical approach
    Analiza stabilności płytkiego tunelu metra z wykorzystaniem metod numerycznych
    Autorzy:
    Monjezi, M.
    Rahmani, B. N.
    Torabi, S. R.
    Singh, T. N.
    Powiązania:
    https://bibliotekanauki.pl/articles/219211.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    modelowanie numeryczne
    gwoździowanie gruntu
    drążenie tuneli przy pomocy tarcz
    szkody górnicze
    osiadanie gruntu
    numerical modelling
    soil nailing
    shield tunnelling
    subsidence
    Opis:
    In this paper, an attempt has been made to use numerical modelling for simulating a long halt in construction process at a shallow depth metro tunnel and investigate the effects of soil nailing to increase the tunnel face strength. Finite difference software FLAC with high applicability in a continuum environment was adopted for this study. The tunnel is being excavated for Tehran metro project. Shield tunnelling with roadheader and back hoe cutting tools is applied in the excavation process. Mohr-Coulomb elasto-plastic constitutive law is considered to model the ground. After two months halting in excavation process, tunnel instability and ground subsidence were recorded in thirteen different monitoring points. Numerical simulation results showed a close approximation (11-16%) between measured and FLAC computed displacements of the tunnel crown in case of unsupported face, which is in close proximity and a proof indicates the reliability of simulation. Also, simulation results exhibit a significant reduction in the ground subsidence and tunnel instability in case of supported face by means of the soil nailing.
    W artykule podjęto próbę wykorzystanie metod modelowania numerycznego dla potrzeb symulacji dłuższego przestoju prac związanych z budową płytkiego tunelu metra w celu zbadania skutków wzmacniania gruntu dla zwiększenia wytrzymałości tunelu w części czołowej. W badaniach zastosowano oprogramowanie wykorzystujące metodę różnic skończonych FLAC, do zastosowań w środowisku ciągłym. Wykop tunelu wykonywany jest w ramach budowy metra w Teheranie. Kopanie tunelu odbywa się przy pomocy urządzeń tarczowych do drążenia tuneli oraz urządzeń podsiębiernych do urabiania. Do modelowania gruntu zastosowano model sprężysto-plastyczny Mohra-Coulomba z wykorzystaniem równania konstytutywnego. Po dwumiesięcznym przestoju w pracach budowlanych, zarejestrowano wielkości niestabilności tunelu oraz osiadania gruntu w trzynastu równych punktach pomiarowych. Wyniki symulacji numerycznych wykazały wysoką zbieżność (11-16%) pomiędzy wartościami zmierzonymi a przemieszczeniami obliczonymi przy wykorzystaniu oprogramowania FLAC dla stropu tunelu w niepodpartej części czołowej, co potwierdza wiarygodność wyników symulacji. Ponadto, wyniki symulacji wykazują znaczne zmniejszenie osiadania gruntu i niestabilności tunelu w części czołowej tunelu wzmocnionej przez podbijanie gruntu.
    Źródło:
    Archives of Mining Sciences; 2012, 57, 3; 535-545
    0860-7001
    Pojawia się w:
    Archives of Mining Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Studies on the effect of coal particle size on biodepyritization of high sulfur coal in batch bioreactor
    Autorzy:
    Singh, S.
    Srichandan, H.
    Pathak, A.
    Gahan, Ch. S.
    Lee, S.
    Kim, D. J.
    Kim, B. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/778523.pdf
    Data publikacji:
    2015
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    biodepyritization
    coal
    pyrite
    stirred tank bioreactor
    Opis:
    The moderate thermophilic mix culture bacteria were used to depyritize the Illinois coal of varying particle sizes (-100 μm, 100-200 μm, +200 μm). Mineral libration analysis showed the presence of pyrite along with other minerals in coal. Microbial depyritization of coal was carried out in stirred tank batch reactors in presence of an iron-free 9K medium. The results indicate that microbial depyritization of coal using moderate thermophiles is an efficient process. Moreover, particle size of coal is an important parameter which affects the efficiency of microbial depyritization process. At the end of the experiment, a maximum of 75% pyrite and 66% of pyritic sulphur were removed from the median particle size. The XRD analysis showed the absence of pyrite mineral in the treated coal sample. A good mass balance was also obtained with net loss of mass ranging from 5-9% showing the feasibility of the process for large scale applications.
    Źródło:
    Polish Journal of Chemical Technology; 2015, 17, 1; 97-102
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental Studies on Advanced Sheet Explosive Formulations Based on 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and Hydroxyl Terminated Polybutadiene (HTPB), and Comparison with a RDX-based System
    Autorzy:
    Jangid, S. K.
    Talawar, M. B.
    Singh, M. K.
    Nath, T.
    Sinha, R. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/358055.pdf
    Data publikacji:
    2016
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    hazardous materials
    sheet explosive
    explosive reactive armour (ERA)
    CL-20
    RDX
    Opis:
    The present investigation reports the use of 2,4,6,8,10,12-hexanitro2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) in sheet explosive formulations. In this study, hydroxyl terminated polybutadiene (HTPB) based sheet explosives were prepared incorporating the powerful explosive CL-20 as a partial replacement for hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX). The effects of incorporating CL-20 on the performance, sensitivity, thermal and mechanical properties of the sheet explosive compositions are reported. Sheet explosive formulation containing 80% of RDX and 20% of HTPB-binder was studied as control sample. HTPBbinder consisted of 12% HTPB, 2.9% dioctyl adipate (DOA) and 5.1% dioctyl phthalate (DOP). HTPB was cured with 4,4’-methylene diphenyl di-isocyanate (MDI) to form urethane linkages. The incorporation of 20% of CL-20 in place of RDX led to a remarkable increase in the velocity of detonation (VOD), of the order of 7680 m/s, and to better mechanical properties in terms of tensile strength (1.14 MPa) compared to the control formulation [RDX /HTPB-binder (80/20)]. The 20% CL-20 incorporated sheet explosive formulation also showed remarkable increases in impact and shock sensitivity. Thermal analysis of the sheet explosive compositions has also been carried out using differential scanning calorimetry (DSC).
    Źródło:
    Central European Journal of Energetic Materials; 2016, 13, 1; 135-147
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Studies on High Burning Rate Composite Propellant Formulations using TATB as Pressure Index Suppressant
    Autorzy:
    Mehilal, -
    Jawalkar, S.
    Kurva, R.
    Sundaramoorthy, N.
    Dombe, G.
    Singh, P. P.
    Bhattacharya, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/951502.pdf
    Data publikacji:
    2012
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    composite propellant
    ammonium perchlorate
    TATB
    pressure index suppressant
    Opis:
    High burning rate propellant compositions are generally used in gas generators to eject missile from canister. Because of high burning rate, pressure index of the composition increases during burning. To reduce the pressure index, a high burning rate composite propellant formulations (~20 mm/s) based on AP/HTPB/Al have been prepared by incorporating TATB and studied in detail for viscosity build-up, thermal and mechanical properties, sensitivity as well as burning rate and pressure index (n). The data indicate that there is a decrease in end of mix viscosity on increasing the percentage of TATB. The same trend was also observed with mechanical properties while significant improvement in overall thermal stability was clearly observed. The sensitivity data indicate that impact and friction values show decreasing trend infer better safe to handle. The burn rate data reveal that on addition of TATB from 0.5 to 2% decrease in burning rate was not observed while on addition of further TATB up to 5% and beyond this significant decrease in burning rate was observed. The data on pressure index (n) also reveal that TATB is very effective in reducing the 'n' value up to 2% and beyond this 'n' value increases close to standard composition. The data on 'n' value reveal that it reduces from 0.47 to that of standard composition to 0.36 for the compositions containing TATB up to 2.0% in the pressure range of 60-90 kg/cm2.
    Źródło:
    Central European Journal of Energetic Materials; 2012, 9, 3; 237-249
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Passerine birds supporting cross pollination in Erythrina stricta Roxb.
    Autorzy:
    Khanduri, V.P.
    Kumar, K.S.
    Sharma, C.M.
    Riyal, M.K.
    Kar, K.
    Singh, B.
    Sukumaran, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/2078260.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Instytut Dendrologii PAN
    Tematy:
    Ornithophily
    pollination
    mating system
    geitonogamy
    pollen grains
    Opis:
    Erythina stricta is an ecologically important tree species in the rainforests of India and its nectar within the flowers contributes to birds’ diet and survival. Reports on the pollination of this species have not been published so far. We therefore explore the reproductive system of this tree species which has great significance to its ecosystem. Birds have an important role in the reproduction of trees through pollination particularly in tropical areas where reproductive success mostly depends on animal pollinator interactions. Study of visitation and nectar feeding behaviour of birds alongwith breeding system assessment of Erythina stricta. Birds visiting and foraging behaviour was observed during Erythrina stricta flowering season in an indian tropical rainforest. Reproductive system was assessed through controlled pollination experiments. Thirteen bird species were recorded visiting and foraging nectar from the flowers of Erythrina stricta. The maximum numbers of visits recorded were from the Red-vented Bulbul (Pycnonotus cafer, Pycnonotidae). The nectar feeding birds were, either (i) potential pollinator with long bills (e.g. Pycnonotus spp., Chloropsis aurifrons, and Dicrurus spp.) or (ii) nectar robbers with comparatively shorter bills (e.g. Zosterops palpebrosa, Stachyris ruficeps, Macronous gularis, Heterophasia glaciris). Controlled pollination experiments revealed high degree of cross pollination (xenogamy) and self-incompatibility in E. stricta. Birds were more frequent in early mornings and their foraging activity was also observed during evening hours; the frequency however, declined with respect to nectar availability. Long corolla tubes of E. stricta could restrict access to nectar collecting bees
    Źródło:
    Dendrobiology; 2021, 85; 117-126
    1641-1307
    Pojawia się w:
    Dendrobiology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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