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Wyszukujesz frazę "Singh, J." wg kryterium: Autor


Tytuł:
Volumetric, Optical, Acoustical and Viscometric Study of Molecular Association in Binary Mixtures of Butylamine with 1-Butanol and Tert-Butanol
Autorzy:
Singh, S.
Parveen, S.
Shukla, D.
Gupta, M.
Shukla, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/2047348.pdf
Data publikacji:
2007-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.35.+d
62.60.+v
82.60.Lf
Opis:
Density (ρ), refractive index (n), ultrasonic velocity (u), and viscosity (η) were measured for the binary mixtures formed by butylamine with 1-butanol and tert-butanol at temperatures 293, 303, and 313 K over the entire composition range. Excess molar volume V$\text{}_{m}^{E}$, molar refraction deviation ΔR$\text{}_{m}$, deviation in ultrasonic velocity Δu, viscosity deviation Δη, and excess Gibb's free energy of activation for viscous flow ΔG$\text{}^{*E}$ were derived from the experimental data and the computed results were fitted to the Redlich-Kister polynomial equation. The values of V$\text{}_{m}^{E}$, ΔR$\text{}_{m}$, Δu, Δη, and ΔG$\text{}^{*E}$ were plotted against the mole fraction of butylamine. The observed positive and negative values of excess parameters for both the mixtures were explained on the basis of intermolecular interactions present in these mixtures. The higher negative values of V$\text{}_{m}^{E}$ and ΔR$\text{}_{m}$ and positive values of Δu, Δη, and ΔG$\text{}^{*E}$ for butylamine + 1-butanol mixture suggest that specific interactions are taking place in butylamine + 1-butanol mixture, while weak dipole-dipole induced forces and dispersive forces seem to be responsible for butylamine + tert-butanol mixture. Furthermore, different empirical relations were used to correlate the binary refractive indices. An excellent agreement was found between experimental and theoretical values.
Źródło:
Acta Physica Polonica A; 2007, 111, 6; 847-858
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two-dimensional deformation in a thermoelastic solid with microtemperatures subjected to an internal heat source
Autorzy:
Ailawalia, P.
Budhiraja, S.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/265902.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
termoelastyczność
źródło ciepła
mikrotemperatura
thermoelasticity
internal heat source
normal mode
microtemperatures
Opis:
The purpose of this paper is to study the two dimensional deformation in a generalized thermoelastic medium with microtemperatures having an internal heat source subjected to a mechanical force. The force is acting along the interface of generalized thermoelastic half space and generalized thermoelastic half space with microtemperatures having an internal heat source. The normal mode analysis has been applied to obtain the exact expressions for the considered variables. The effect of internal heat source and microtemperatures on the above components has been depicted graphically.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 1; 5-21
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermoacoustical Excess Properties of Binary Liquid Mixtures - A Comparative Experimental and Theoretical Study
Autorzy:
Yasmin, M.
Singh, K.
Parveen, S.
Gupta, M.
Shukla, J.
Powiązania:
https://bibliotekanauki.pl/articles/1808024.pdf
Data publikacji:
2009-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.35.+d
62.60.+v
82.60.Lf
Opis:
Specific heat ratio (γ), pseudo-Grüneisen parameter (Γ), heat capacity $(C_p)$ and effective Debye temperature $(θ_{D})$ for binary system of tetrahydrofuran with o-cresol and methanol respectively, were calculated using the experimentally measured densities, velocities and viscosities of the pure liquids and their mixtures over the whole composition range and at T = 293, 303, 313 K. The excess pseudo-Grüneisen parameter $(Γ ^{E})$, excess molar isentropic compressibility $(K_{s}^{E})$ and excess acoustic impedance $(Z^{E})$ were also calculated. The excess deviation functions have been correlated using Redlich-Kister polynomial equation. The observed values of the excess parameters plotted against the mole fraction of tetrahydrofuran have been explained on the basis of intermolecular interaction suggesting strong interaction in tetrahydrofuran + o-cresol than in tetrahydrofuran + methanol. Partial molar isentropic compressibility at infinite dilution and their excess values were calculated for each component. Sanchez theory, Goldsach-Sarvas volume fraction statistics, Sudgen's relation, Flory-Patterson-Rastogi and Brock and Bird model were used with the Aurebach relation to compute theoretically the values of ultrasonic velocities at varying temperatures. The velocity deviations were estimated in terms of average percentage deviations. Internal pressure for both the systems were calculated theoretically and discussed on the basis of relative applicability of the models in theoretical estimations. The isothermal compressibility $(k_T)$, for these binary mixtures were theoretically evaluated by using the Flory statistical theory and five hard sphere models and compared with the experimental values.
Źródło:
Acta Physica Polonica A; 2009, 115, 5; 890-900
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The onset of convection in a rotating multicomponent fluid layer
Autorzy:
Prakash, J.
Singh, V.
Kumar, R.
Kumari, K.
Powiązania:
https://bibliotekanauki.pl/articles/281283.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
multicomponent convection
principle of exchange of stabilities
oscillatory motions
complex growth rate
concentration Rayleigh number
Lewis number
Opis:
The onset of convective instability is analysed in a rotating multicomponent fluid layer in which density depends on n stratifying agents (one of them is heat) having different diffusivities. Two problems have been analysed mathematically. In the first problem, a sufficient condition is derived for the validity of the principle of the exchange of stabilities. Further, when the complement of this condition holds good, oscillatory motions of neutral or growing amplitude can exist, and thus it is important to derive upper bounds for the complex growth rate of such motions when at least one of the bounding surfaces is rigid so that exact solutions of the problem in closed form are not obtainable. Thus, as the second problem, bounds for the complex growth rates are also obtained. Above results are uniformly valid for quite general nature of the bounding surfaces.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 2; 477-488
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
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:
Studies on Curing of an Aluminized Ammonium Perchlorate Composite Propellant Based on Nitrile Butadiene Rubber Using a Quinol Ether of 1,4-Benzoquinone Dioxime
Autorzy:
Singh, Sudhir
Raveendran, Sidharth
Kshirsagar, Dhirendra R.
Gupta, Manoj
Bhongale, Chetan J.
Powiązania:
https://bibliotekanauki.pl/articles/27788068.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
dinitrosobenzene
nitrile butatadiene rubber
quinol ether
unsaturated rubber
Opis:
The isocyanate-based curing agents used for polyurethane are toxic and hygroscopic in nature. In the present work, an alternate approach was adopted, a reaction between the unsaturated rubber having an α-methylene hydrogen atom and a dinitrosobenzene (DNB) - generating system (quinol ether of 1,4-benzoquinone dioxime, QE) without a catalyst, thus generating a cured system. QE is a novel curing agent for propellant applications which imparts the necessary curing. The curing reaction between nitrile butatadiene rubber (NBR) and quinol ether (QE) was studied by FTIR and the results revealed the formation of anil groups (Ar–C=N). The anil group results from the reaction between NBR and DNB, generated on decomposition of QE. Propellant formulations were prepared with variation of the curing agent from 0.2 to 0.5%. The composition and rheological, mechanical, ballistic and thermal properties of the resulting cured systems were investigated. The viscosity and spreadability were suitable for casting. The tensile strength, modulus, and hardness show an increasing trend and the elongation decreases on varying QE from 0.2 to 0.5% in the propellant. However, all of the compositions showed nearly the same burning rate and pressure exponent. The QE based curing system is non-hygroscopic and has extremely low toxicity. The experimental results revealed that the proposed curing agent may find application in explosives and propellants.
Źródło:
Central European Journal of Energetic Materials; 2022, 19, 1; 18--38
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on biosynthesis of silver nanoparticles using Rhizopus sp. and its antibacterial efficacy on E. coli MDR strains
Autorzy:
Hiremath, J.
Rathod, V.
Ninganagouda, S.
Singh, D.
Prema, K.
Powiązania:
https://bibliotekanauki.pl/articles/11479.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
biosynthesis
silver nanoparticle
Rhizopus
antibacterial activity
Escherichia coli
multidrug resistance
nanotechnology
Opis:
Nanotechnology is a field that is burgeoning day by day, making an impact in all spheres of human life. Biological methods of synthesis have paved way for the “greener synthesis” of nanoparticles and these have proven to be better methods due to slower kinetics, they offer better manipulation and control over crystal growth and their stabilization. In this context we have investigated extracellular biosynthesis of silver nanoparticles (AgNPs) using cell-free extract of Rhizopus spp.. Formation of AgNPs was indicated by the change in the colour of the cellfree extract from yellow to dark brown under static condition after 48 hrs of incubation. Characterization of AgNPs was carried out by UV-Vis Spectroscopy which gave sharp plasmon resonance peak at 429 nm corresponding to spherical shaped nanoparticles. Transmission electron microscopy (TEM) micrograph showed formation of well-dispersed AgNPs in the range of 25-50 nm. Scanning electron microscopy (SEM) showed the particles to be uniformly dispersed without agglomeration with smooth morphology. EDS showed the presence of elemental silver at 3kev. X-ray diffraction (XRD)-spectrum of the AgNPs exhibited 2θ¸ values corresponding to nanocrystal. These biosynthesized AgNPs were used to study their antimicrobial activity against Multi-drug resistant (MDR) E. coli strains, by Agar diffusion method. Zone of inhibition was measured. Synthesis of nanosized particles with antibacterial properties, which are called "nanoantibiotics", is of great interest in the development of new pharmaceutical products.
Źródło:
International Letters of Natural Sciences; 2014, 18
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Static analysis of functionally graded plate using nonlinear classical plate theory with von-Karman strains
Autorzy:
Singh, S. J.
Harsha, S. P.
Powiązania:
https://bibliotekanauki.pl/articles/265766.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
metoda Naviera
teoria płyt
odkształcenie
functionally graded materials (FGM) plate
Von-Karman strain
nonlinear classical plate theory (NLCPT)
Navier’s method
Opis:
The present study is based on the nonlinear bending analysis of an FGM plate with Von-Karman strain based on the non-linear classical plate theory (NLCPT) with in-plane displacement and moderate rotation. Non-linear bending analysis based on stresses and transverse deflections is then carried out for the plate for the complex solution obtained using an analytical method viz. Navier’s method. The equations of motion and boundary conditions are obtained using the Principle of Minimum Potential Energy (PMPE) method and material property is graded in thickness direction according to simple power-law distribution in terms of volume fractions of the constituents. The effect of the span-to-thickness ratio and FGM exponent on the maximum central deflection and stresses are studied. The results show that the response is transitional with respect to ceramic and metal and the complex solution predicts the real behavior of stresses and deflections in the functionally graded plate. The functionally graded plate is found to be more effective for moderately thick and thick plates, which is inferred by a complex nature of the solution. For FGM plates, the transverse deflection is in-between to that of metal and ceramic rich plates. The complex nature of the solution also gives information about the stress distribution in the thickness direction.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 3; 707-726
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sequence optimization of hole-making operations for injection mould using shuffled frog leaping algorithm with modification
Autorzy:
Dalavi, A. M.
Pawar, P. J.
Singh, T. P.
Powiązania:
https://bibliotekanauki.pl/articles/407274.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hole-making operations
injection mould
shuffled frog leaping algorithm with modification
Opis:
Tool travel and tool switch planning are the two major issues in hole-making operations of industrial part which involves drilling, tapping etc. operations. It is necessary to find the sequence of operations, which minimizes the total non productive time and tool switch time of hole-making operations depending upon the hole location and the tool sequence to be followed. In this work, an attempt is made to reduce total non-productive time and tool switch time of hole-making operations by applying a relatively new algorithm known as shuffled frog leaping with modification for the determination of optimal sequence of operations. In order to validate the developed shuffled frog leaping algorithm with modification, it is applied on six different problems of holes and its obtained results are compared with dynamic programming (DP), ant colony algorithm (ACO), and immune based evolutionary approach (IA). In addition, an application example of injection mould is considered in this work to demonstrate the proposed approach. The result obtained by shuffled frog leaping algorithm with modification is compared with those obtained using ACO, particle swarm optimization (PSO) algorithm and IA. It is observed that the results obtained by shuffled frog leaping algorithm with modification are superior to those obtained using ACO, PSO and IA for the application example presented.
Źródło:
Management and Production Engineering Review; 2018, 9, 3; 71-78
2080-8208
2082-1344
Pojawia się w:
Management and Production Engineering Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sensitivity enhancement of metamaterial-based surface plasmon resonance biosensor for near infrared
Autorzy:
Pal, S.
Prajapati, Y. K.
Saini, J. P.
Singh, V.
Powiązania:
https://bibliotekanauki.pl/articles/173477.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
metamaterials
sensor sensitivity
reflectance
evanescent field
Opis:
The present study investigates the angular response and sensitivity of a surface plasmon resonance biosensor with metamaterial, by taking the advantage of the remarkable property of metamaterials. The proposed biosensor numerically shows that silver with a metamaterial layer enhances the sensitivity. The thickness of metamaterial and silver layer has been optimized. On comparing these results with a conventional surface plasmon resonance biosensor, it is observed that the sensitivity of the proposed biosensor is improved by introducing the metamaterial. The proposed biosensor has a sensitivity 6.3124 times higher than that of the conventional surface plasmon resonance sensor.
Źródło:
Optica Applicata; 2016, 46, 1; 131-143
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of corrugated interface on incident qSV-wave in monoclinic elastic half-spaces
Autorzy:
Singh, S. S.
Lalvohbika, J.
Powiązania:
https://bibliotekanauki.pl/articles/264383.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
współczynnik odbicia
współczynnik transmisji
prędkość fazowa
qSV and qP-waves
reflection and transmission coefficients
monoclinic medium
corrugated interface
phase velocity
Opis:
This paper is concerned with the problem of reflection and transmission of elastic waves due to an incident plane qSV-wave at a corrugated interface between two dissimilar monoclinic elastic half-spaces. Due to the corrugated nature of the interface, there exist regularly and irregularly reflected and transmitted elastic waves. Using Rayleigh’s method of approximation, the reflection and transmission coefficients of regular and irregular waves are obtained for the first order of approximation. We have found that these coefficients are functions of the angle of incidence, elastic constants, corrugation and the frequency parameter. These coefficients are obtained for a special type of interface, z =dcos py. We have computed these coefficients for a particular model and discussed the effects of corrugation and frequency parameter.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 3; 727-750
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Refractive Indices, Order Parameter and Optical Transmittance Studies of a Nematic Liquid Crystal Mixture
Autorzy:
Singh, A. K.
Manohar, R.
Shukla, J. P.
Biradar, A. M.
Powiązania:
https://bibliotekanauki.pl/articles/2047089.pdf
Data publikacji:
2006-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.30.-v
42.70.Df
Opis:
Measurements of ordinary refractive index, birefringence, density, and order parameter were made on a technologically important nematogen and the data obtained for its nematic and isotropic phase were reported. A modified wedge method was used for the measurement of the birefringence (δ n). The nematic-isotropic phase transition temperature matches very well as is exhibited from the value of refractive indices and densities obtained using different techniques. The optical anisotropy and density data were used to determine the order parameter and principal polarizability of the nematic mixture using the Vuks approach and their temperature dependence was discussed. The macroscopic order parameter was obtained and compared with microscopic order parameter. These two values agree very well.
Źródło:
Acta Physica Polonica A; 2006, 110, 4; 485-493
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quasi Locally Connected Spaces and Pseudo Locally Connected Spaces
Autorzy:
Kohli, J.K.
Singh, D.
Tyagi, B. K.
Powiązania:
https://bibliotekanauki.pl/articles/746262.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
almost (quasi, pseudo) locally connected space
regular open set
regular \(F_\sigma\)-set
\(\theta\)-open set
\(D_\delta\)-completely regular space
quasi \(\theta\)-continuous function
coreflective subcategory
Opis:
Two new generalizations of locally connected spaces called ‘quasi locally connected spaces’ and ‘pseudo locally connected spaces’ are introduced and their basic properties are studied. The class of quasi locally connected spaces properly contains the class of almost locally connected spaces (J. Austral. Math. Soc. 31(1981), 421–428) and is strictly contained in the class of pseudo locally connected spaces which in its turn is properly contained in the class of sum connected spaces (Math. Nachrichten 82(1978), 121-129; Ann. Acad. Sci. Fenn. A I Math. 3(1977), 185–205). Product and subspace theorems for quasi (pseudo) locally connected spaces are discussed. Their preservation under mappings and their interplay with mappings are outlined. Function spaces of quasi (pseudo) locally connected spaces are considered. Change of topology of a quasi (pseudo) locally connected space is considered so that it is simply a locally connected space in the coarser topology. In contradistinction with almost locally connected spaces, quasi (pseudo) locally connected spaces constitute a coreflective subcategory of TOP.
Źródło:
Commentationes Mathematicae; 2010, 50, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Propagation of spherical shock waves in a dusty gas with radiation heat-flux
Propagacja sferycznych fal uderzeniowych w zanieczyszczonym gazie z uwzględnieniem radiacyjnej wymiany ciepła
Autorzy:
Singh, K. K.
Vishwakarma, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/281502.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
fale uderzeniowe
radiacyjna wymiana ciepła
shock waves
radiation heat-flux
Opis:
The propagation of spherical shock waves in a dusty gas with radiation heat-flux and exponentially varying density is investigated in the paper. The equilibrium flow conditions are assumed to be maintained, and the radiation is considered to be of a diffusion type for an optically thick grey gas model. The shock wave moves wit h variable velocity and the total energy of the wave is non-constant. Non-similar solutions are obtained, and the effects of variation of the radiation parameter and time are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) of the ratio of the density of solid particles to the initial density of gas on the flow variables in the region behind the shock are also investigated.
W pracy zajęto się problemem propagacji sferycznych fal uderzeniowych o wykładniczym rozkładzie gęstości w zanieczyszczonym gazie z uwzględnieniem radiacyjnej wymiany ciepła. Założono równowagowe warunki przepływu czynnika, a samą radiację przyjęto typu dyfuzyjnego w modelu optycznie nieprzezroczystego gazu. Fala uderzeniowa przemieszcza się ze zmienną prędkością, a całkowita energia fali również się zmienia. W analizie otrzymano rozwiązania niepodobne przy rozważaniu wpływu czasu i zmienności strumienia radiacji. Zbadano ponadto efekt wzrostu koncentracji masy cząstek stałych zanieczyszczenia oraz stosunku gęstości tych cząstek do początkowej gęstości gazu na parametry przepływu w obszarze bezpośrednio za czołem fali.
Źródło:
Journal of Theoretical and Applied Mechanics; 2007, 45, 4; 801-817
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł

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