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Tytuł:
Vertical Fall of a Body Under Free Motion
Autorzy:
Pluta, Z.
Hryniewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/411583.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
material body
kinetics
free fall
Path/way length
velocity
acceleration
Inertia acceleration
Gravitation acceleration
time constant
Way constant
Gravitation number constant
Opis:
The paper aims at the kinetics of a body under free fall, especially free body motion, the motion occurring in the Earth environs space, that is in the range of the gravity action. A new adequate theory of such a motion, opening new not known kinetic magnitudes, has been elaborated. This theory has its source, which is the dependence of the way length on time. That is the way characteristics created in this work. The worked out theory has been verified by experiment, referred to two different realities. One of them was the body motion in the air environment of the Earth environs space, with the second one occurring in a determined machining space-time. The adequate earth acceleration/gravity has been calculated taking advantage of the theory elaborated; and its value, as indicated, is equal 3.85 mźs-2. Two kinds of accelerations have been separated: inertial and gravitational. The relations occurring between their values on the neighbouring potential fields, unstable, and stable, have been discovered. That discovery indicates on the existence of quantum nature of gravitation.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 4; 56-72
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dielectric studies of nano structured BaTi1-xSnxO3 solid solutions
Autorzy:
Bitra, H. Ch. R.
Prasad, B. B. V. S. V.
Powiązania:
https://bibliotekanauki.pl/articles/412300.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
BTSx
XRD
SEM
dielectric constant
Opis:
BaTi1-xSnxO3 (BTSx) ceramics had been prepared by temperature sintering technique. Initially, the samples were calcined at a temperature at 900 °C for 2 hours, after that ball milling was done and then the samples were sintered at a temperature of 1150 °C for 3 hours. X-ray diffractometry, Scanning Electron Microscopy, Energy Dispersive Spectroscopy and Dielectric measurements were carried out and structural, micro structural and elemental analyses were discussed in brief.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 191-201
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficiency evaluation of Luffa cylindrica and Mucuna sloanei seeds in dye removal: A news approach
Autorzy:
Nnaji, P. C.
Okoye, C. C.
Umeuzuegbu, J. U.
Powiązania:
https://bibliotekanauki.pl/articles/1031647.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Luffa cylindrica
Mucuna sloanei
coag-flocculation rate constant
critical coag-flocculation rate constant
dye-based wastewater
Opis:
The use of Luffa cylindrica (LC) and Mucuna sloanei (MS) seeds as coagulants in the removal of dye by coag-flocculation was evaluated using a new approach. The approach uses the coag-flocculation rate constant K11, calculated using experimental data obtained while using LC and MS as coagulants in coag-flocculation process as a valid indicator to determine the optimum condition. The research also applied criterion for critical coag-flocculation rate constant Kc to satisfy World Health Organization’s minimum allowable level of suspended substance for wastewater discharge. In the criterion K11 ≥ Kc indicates better performance. The results indicated that K11 of 0.00214 L/mg·min for LC and 0.00208 L/mg·min for MS surpassed 0.00016 L/mg·min Kc value. This was observed for LC and MS at pH 2, but 1400 mg/L and 1200 mg/L, respectively. From the above, in accordance with the WHO guideline, the dosage of both coagulants meets the requirement. The solution pH could not meet the standard. Nonetheless, MS satisfied the requirement at pH 6, for dosage and pH. These results correspond to what was obtained experimentally. Therefore, in coag-flocculation kinetic modeling, this novel approach can be considered to track the efficiency of these sensitive factors in water treatment plants to meet the effluent quality requirements.
Źródło:
World Scientific News; 2020, 146; 184-201
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shifted Chebyshev-Lanczos polynomials
Autorzy:
Caltenco, J. H.
López-Bonilla, J.
Peña-Rivero, R.
Powiązania:
https://bibliotekanauki.pl/articles/1177824.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Feigenbaum constant
Modified Lanczos polynomials
Pascal triangle
Opis:
We show an algorithm for to express in terms of the modified Chebyshev-Lanczos polynomials , which is important to reduce the degree of a polynomial in the interval [0, 1]. Besides, with the use of into logistic map we obtain a simple geometric interpretation of the Feigenbaum´s universal constant.
Źródło:
World Scientific News; 2018, 99; 222-226
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-adiabatic universe and the redshift
Autorzy:
Gupta, Rajendra P.
Powiązania:
https://bibliotekanauki.pl/articles/1163142.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Cosmic microwave background radiation
Cosmological constant
Cosmology theory
Distance scale
Distances and redshifts
Galaxies
General relativity
Hubble constant
Supernovae
Opis:
We have relaxed the constraint of adiabatic universe used in most cosmological models and shown that the new approach provides a better fit to the supernovae Ia redshift data with a single parameter, the Hubble constant, than the standard ΛCDM model with two parameters, the Hubble constant and the cosmological constant. The new approach, developed within the confines of the cosmological principle, yields the Hubble constant value 69.01 (±0.53) km s-1 Mpc-1. The cosmological constant may thus be considered as a manifestation of a non-adiabatic universe that is treated as an adiabatic universe.
Źródło:
World Scientific News; 2018, 110; 210-218
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chenodeoxycholic acid: A Physicochemical study
Autorzy:
Baluja, Shipra
Bhesaniya, Kapil
Powiązania:
https://bibliotekanauki.pl/articles/1193963.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Chenodeoxycholic acid
Dissociation constant
acoustical parameters
thermal analysis
Opis:
Some physicochemical properties such as dissociation constant, acoustical parameters and thermal studies of acid are studied in methanol and 1,4-dioxane at 298.15 K. The dissociation constant of Chenodeoxycholic acid is evaluated in binary mixtures (of methanol / 1,4-dioxane + water) by two methods; half-integral and average methods. The acoustical properties have been evaluated from experimental data of density, viscosity and ultrasonic velocity. It is observed that in both the solvents, strong solute-solvent interactions exist. Thermal degradation of Chenodeoxycholic acid is found to be a single step process.
Źródło:
World Scientific News; 2015, 18; 115-127
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Static quenching of ruthenium(II)-polypyridyl complexes by gallic acid and quercetin in aqueous and micellar media
Autorzy:
Sheeba, D
Gnana Raj, G. A.
Powiązania:
https://bibliotekanauki.pl/articles/412659.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Ru(II)-polypyridyl complex
electron transfer
quenching
association constant
Opis:
The reactions of gallic acid and quercetin with the excited state Ru(II) complexes proceed through photoinduced electron transfer reaction in sodium dodecyl sulfate (SDS) and aqueous media at pH 11 and has been studied by luminescence quenching technique. The static nature of quenching is confirmed from the ground state absorption studies in both the media. The observed quenching rate constant (kq) values are sensitive to the nature of the ligand, medium and the structure of the quenchers. The electrostatic interaction of the cationic complexes with the anionic micelle reduces the kq values in SDS compared to that in aqueous medium.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 13, 1; 21-31
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical study of ferroelectric triglycine sulphate (TGS) crystal in external electric fields
Autorzy:
Upadhyay, T. Ch.
Nautiyal, A.
Powiązania:
https://bibliotekanauki.pl/articles/412113.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ferroelectric
Green's functions
anharmonic
dielectric constant
loss tangent
coustic attenuation
Opis:
A modified two sub-lattice pseudospin-lattice coupled mode model of Mitsui et al [Phys. Rev., 111 (1958) 1259] by adding third, fourth order phonon anharmonic interaction and external electric field terms has been applied to ferroelectric triglycine sulphate crystal. Electric field dependence of ferroelectric, dielectric and acoustical properties has been studied. With the help of double time temperature dependent Green’s function method, expressions for shift, width, soft mode frequency, dielectric constant, loss tangent and acoustic attenuation have been derived. Numerically calculations have been made and results have been compared with experimental data reported by Bye et al [Ferroelectrics 4 (1974) 243] and Shreekumar et al [Ferroelectrics 160 (1994) 23] for TGS crystal and a good agreement has been observed.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 6; 54-65
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Novel Modeling of the Work-Hardening Curve
Autorzy:
Pluta, P.
Hryniewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/411581.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Hardening curve
yield stress
Relative deformation
Relative deformation constant;
Absolute strain constant
Stress potential fields
Strain potential fields
Yield force
Plastic rigidity
Plastic energy
Yield work
Opis:
The paper aims at a critical analysis of the existent description of plastic strengthening/ work-hardening curve. The adequate description of the curve, having a physical sense, has been proposed. The description begins from the very source which is the primary, general differential equation. That source was used to formulate the characteristics of the studied system. Then the analytical solution of the dependence between the yield stress and the relative deformation is provided. The description of the work-hardening curve has been developed to further form a proper dependence of the yield force on the absolute yield strain. Other functional characteristics, namely the coefficient of the plastic rigidity, yield work, and the plastic potentials, have also been formed.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 4; 73-90
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics of Flexibly Fixed Operating Element of a Rotating Device
Autorzy:
Pluta, Z.
Hryniewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/412254.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
kinetics
susceptibility
device
potential field
time constant
body trajectory
path length
velocity
acceleration
Opis:
The work covers the adequate kinetics of the flexibly fixed working element of a rotating device. First the literature background of the problem has been presented, turning the attention on such systems where the phenomenon of centrifugal displacement of a body due to the rotating of the system occurs. Then the general characteristics of the complex motion of working element has been described. The core of the work is the description of the variable component motions, with the starting point of the description being the source differential equation, presenting this type of dependence of the path length on time. The accelerated angular motion and retarded radial motion have been separated, describing these component motions as the function of time. Based on these detailed descriptions, the trajectory equation of working element, the derivatives and further kinetic magnitudes, have been derived. In the conclusion, the cognitive and practical qualities of the presented solutions of the title problem, have been accented.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 3; 67-84
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Inverse Reaction Cross Sections for Unit Rate Cost Model for Pricing Weld Mesh Reinforcement in Construction Projects
Autorzy:
Samuel, Egwunatum I.
Akpokodje, I. O.
Powiązania:
https://bibliotekanauki.pl/articles/1193018.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Aggregation
Cost model
Estimate
Labour output constant
Time and motion study
Unit rate
Opis:
The subsisting methods of unit rate pricing in the construction industry are either determinate on immediate use basis (analytical pricing) or predictive (cost modeling). The literature cited in this paper showed that cost models used in the industry are spurious. Most of the models attempts to respond to whole building cost from inception to completion with a single formula. This paper argues that on the basis of the units of measurement of the various building elements, a holistic cost model for pricing a complete building cost is a near impossibility. Rather as a negation cost model on the basis of each work item is idealized. Accordingly, this paper responded by generating a unit rate cost model for weld mesh reinforcement. This was done by abstracting and decomposing the relevant cost data and using productivity study by time and motion to determine the various outputs for materials and labour. These were subsequently factored to the cost data to derive the unit rate cost. The paper concludes that the model enjoys flexibility of further mathematical treatment should any of the variable be constrained and recommends that other work items should be modeled if the cost of a project must be known and this model should be used to justify contractor’s tender for weld mesh reinforcement bid.
Źródło:
World Scientific News; 2016, 28; 84-100
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamics of uni-univalent H+/K+ and uni-bivalent H+/Ca2+ ion exchange reactions using nuclear grade resin Indion-223
Autorzy:
Singare, P. U.
Mohammed, A. L. K.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/412388.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ion exchange
nuclear grade resins
cation exchangers
enthalpy change
standard equilibrium constant
Indion-223
Opis:
The present paper deals with the thermodynamic of uni-univalent and uni-bivalent ion exchange reactions using nuclear grade anion exchange resin Indion-223. It was observed that with rise in temperature the equilibrium constants K values for H+/K+ uni-univalet ion exchange reaction increases from 0.01710 to 0.02374. Similarly for H+/Ca2+ uni-bivalet ion exchange reaction the equilibrium constants K values increases from 0.000397 to 0.000639. The increase in K values with rise in temperature for both the reactions indicates its endothermic nature having the enthalpy change values of 22.72 and 38.92 kJ/ mol respectively. The technique used here can be extended further to standardise the process parameters in order to bring about the efficient separation of the desired ionic species from the solution.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 190-198
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative study of uni-univalent H⁺/Na⁺ and uni-bivalent H⁺/Ca²⁺ ion exchange reactions using nuclear grade resin Indion-223
Autorzy:
Singare, P. U.
Mohammed, A. L. K.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/411747.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ion exchange reactions
nuclear grade resins
cation exchange resins
enthalpy
equilibrium constant
Indion-223
Opis:
The present paper deals with the ion exchange equilibrium studies of uni-univalent and uni-bivalent ion exchange reactions using nuclear grade anion exchange resin Indion-223 in H⁺ form towards Na⁺ and Ca²⁺ ions in the solution. It was observed that with rise in temperature the equilibrium constants K values for H⁺/Na⁺ uni-univalet ion exchange reaction increases from 0.01389 to 0.01855. Similarly for H⁺/Ca²⁺ uni-bivalet ion exchange reaction the equilibrium constants K values increases from 0.000397 to 0.000639. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 25.55 and 38.92 kJ/ mol respectively.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 127-135
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of uni-univalent H+/K+ and uni-bivalent H+/Mg2+ ion exchange reactions using nuclear grade resin Indion-223
Autorzy:
Singare, P. U.
Mohammed, A. K. L.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/411848.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ion exchange equilibrium
nuclear grade resins
cation exchange
enthalpy change
equilibrium constant
Indion-223
Opis:
In the present paper the uni-univalent and uni-bivalent ion exchange reactions were investigated using nuclear grade anion exchange resin Indion-223 in H+ form. For both H+/K+ uni-univalet ion exchange reactions and H+/Mg2+ uni-bivalet ion exchange reactions, the equilibrium constant K values increases from 0.01710 to 0.02374 and from 0.000177 to 0.000333 respectively as the reaction temperature rises from 35.0 °C to 45.0 °C. The increase in K values with temperature suggest endothermic ion exchange reactions having the enthalpy change values of 22.72 and 51.46 kJ/ mol respectively. The results of such studies will help in selection of suitable ion exchange resins in order to bring about efficient separation of different ionic species present in the waste water effluents released from nuclear as well as chemical process industries.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 231-239
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and modelling investigation of caesium adsorption on soil samples around DAE facility, India
Autorzy:
Maity, Sukanta
Sandeep, Police
Sahu, Sanjay Kumar
Kumar, A. Vinod
Powiązania:
https://bibliotekanauki.pl/articles/1030685.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
CEC
Laboratory batch method
caesium
chemical parameters
distribution coefficient (Kd)
equilibration time
isotherm
rate constant
Opis:
The kinetics and thermodynamics behind the sorption process of Cs (Caesium) on the soil are important to understand as these studies give information about the mobility of Cs in the environment. In the present study, sorption kinetics and the parameters influencing sorption (viz. time of contact, competing ions, temperature, solution pH and Cs concentration) were studied on the soil samples collected from Tarapur area. Site-specific distribution coefficient (Kd) of Cs was also estimated in soil samples collected from different locations across Tarapur, India using laboratory batch method. The effect of soil parameters (viz. pH, cation exchange capacity, organic matter and CaCO3) on Kd values of Cs was also investigated. The data of Cs adsorption on the soil is well fitted with the pseudo-second-order kinetic equation with the correlation coefficient (R2) value of 0.99. The rate constant (k2) of Cs adsorption (at 25 ºC) on collected soil samples was found to be 3.33×105 g µg-1 min-1. In the present study, Cs adsorption data were well fitted with Freundlich and Dubinin–Radushkevich (D–R) isotherm models. The change of enthalpy (ΔH), entropy (ΔS) and Gibbs free energy (ΔG) were estimated for the Cs adsorption on soil samples. Results showed that the adsorption process was exothermic (ΔH = -3.69 J mol−1) and favoured at a lower temperature. The calculated ΔG value (< 0) indicates that the Cs sorption on the soil is a spontaneous process. The Kd values were found to the range of 58 ± 2 to 275 ± 10 kg-1. The parametric study indicated CEC to have a stronger influence as compared to pH, OM and CaCO3 in the soil samples.
Źródło:
World Scientific News; 2020, 139, 2; 201-220
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł

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