International Letters of Chemistry Physics and Astronomy
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Published By Scipress Ltd.

2299-3843

Author(s):  
Umar Aishetu ◽  
Kamfa A. Salisu ◽  
Bashir Umar

The motion is investigated of dust/gas particles in the elliptic restricted three-body problem (ER3BP) in which the less massive primary is an oblate spheroid and the more massive a luminous body surrounded by a circumbinary disk. The paper has investigated both analytically and numerically the effects of oblateness and radiation pressure of the primaries respectively together with the gravitational potential from a disk on the triangular equilibrium L4,5 of the system, all in the elliptic framework of the restricted problem of three bodies. The important result obtained therein is a move towards the line joining the primaries in the presence of any /all perturbation(s). A significant shift away from the origin as the radiation pressure factor decreases and oblateness of the smaller primary increase is also observed. It is also seen that, all aforementioned parameters in the region of stability have destabilizing tendencies resulting in a decrease in the size of the region of stability except the gravitational potential from the disc. The binary system Ruchbah in the constellation Cassiopeiae is an excellent model for the problem, using the analytic results obtained, the locations of the triangular points and the critical mass parameter are computed numerically.


Author(s):  
Aaron R. Hurst

The supercharged nature of the Earth’s geothermal core can be demonstrated by three thought experiments exhibiting it is tremendously more powerful than any other terrestrial object in the solar system (planet or moon). Identifying a minimum of four byproduct asteroid blast patterns linked to the formation of Earth’s supercharged geothermal core is critical to properly identifying stars that also have these four byproduct asteroid blast patterns. These stars are the most likely to host an Earth-like planet qualified by having a supercharged geothermal core. The Planetary Vaporization-Event (PVE) Hypothesis provides a basis for correlation between the supercharged nature of Earth’s geothermal core and at least 14 listed side effects: (1) the asteroid-wide/planet-scale homogenization and lack thereof of 182W ε for Earth, the Moon, Mars and meteors, (2) the primary and secondary shifting of Earth’s tectonic plates, (3) the solar system wide displacement of Earth’s wayward moons (including Ceres, Pluto, Charon and Orcus) outgassing identical samples of ammoniated phyllosilicates, (4) the formation of asteroids at 100+ times the expected density of a nebular cloud vs. pre-solar grains formation density at the expected density of a nebular cloud, (5) three distinct formation timestamps for all known asteroids within a 5 million year window 4.55+ billion years ago, (6) the estimated formation temperature of CAI at 0.86 billion Kelvin and (7) the remaining chondritic meteorite matrix flash vaporizing at 1,200–1,900 °C, (8) followed by rapid freezing near 0 K, (9) the development of exactly 2 asteroid belts and a swarm of non-moon satellites, (10) particulate size distinction between the 2 asteroid belts of small/inner, large/outer, (11) the proximity of the Trojan Asteroid Groups to the Main Asteroid Belt, (12) observation of a past or present LHB, (13) the development of annual meteor showers for Earth proximal to apogee and/or perigee, (14) the Sun being the most-likely object struck by an asteroid in the inner solar system. Through better understanding of the relevant data at hand and reclassification of the byproducts of supercharging the core of a planet, at least 5 new insights can be inferred and are listed as: (1) the original mass, (2) distance and (3) speed of Earth Mark One, (4) the original order of Earth’s multi-moon formation and (5) the high probability of finding detectable signs of life on a planet orbiting the stars Epsilon Eridani and Eta Corvi. There are at least 6 popular hypothesis that the PVE Hypothesis is in conflict with, listed they are: (1) a giant impact forming the Moon, (2) asteroids being the building blocks of the solar system, (3) the Main Asteroid Belt being the result of a planet that never formed, (4) the LHB being a part of the accretion disk process, (5) the heat in Earth’s core coming primarily from the decay of radioactive elements, (6) the Oort Cloud being the source of ice comets.


Author(s):  
Jagadish Singh ◽  
Tyokyaa K. Richard

This paper studies the classical restricted three-body problem of a carbon atom in the vicinity of two carbon 60 fullerenes (  fullerenes) at the nanoscale. The total molecular energy between the two fullerenes is determined analytically by approximating the pairwise potential energies between the carbon atoms on the fullerenes by a continuous approach. Using software MATHEMATICA, we compute the positions of the stationary points and their stability for a carbon atom at the nanosacle and it is observed that for each set of values, there exists at least one complex root with the positive real part and hence in the Lyapunov sense, the stationary points are unstable. Since only attractive Van der Waals forces contribute to the orbiting behavior, no orbiting phenomenon can be observed for , where the Van der Waals forces becomes repulsive. Although the  orbital is speculative in nature and also presents exciting possibilities, there are still many practical challenges that would need to be overcome before the  orbital might be realized. However, the present theoretical study is a necessary precursor to any of such developments.


Author(s):  
Nnaemeka John Okorocha ◽  
Chijioke E. Omaliko ◽  
Collins C. Osuagwu ◽  
Maureen O. Chijioke-Okere ◽  
Conrad K. Enenebeaku

The prospective of maize cob powder (MCP) as an effective adsorbent for the removal of malachite green (MG) and congo red (CR) dyes from aqueous solution was investigated. The presence of functional groups and pores on maize cob powder were confirmed by FTIR and SEM analysis. Batch adsorption studies were conducted and various parameters such as contact time, adsorbent dosage, initial dye concentration, pH and temperature were examined to observe their effects in the dyes adsorption process. The optimum conditions for the adsorption of MG and CR onto the adsorbent (MCP) was found to be: contact time (60mins), pH (10.0) and temperature (303 K), adsorbent dose (1 g) for an initial MG dye concentration of 50 mg/L and contact time (80mins), pH (2.0) and temperature (343 K) for an initial CR dye concentration of 50 mg/L and adsorbent dose 1.0 g respectively. The experimental equilibrium adsorption data fitted best and well to the Freundlich isotherm model for CR dye adsorption and Langmuir Isotherm for MG adsorption. The maximum adsorption capacity was found to be 13.02 mg/g and 9.41 mg/g for the adsorption of MG and CR dyes respectively. The kinetic data conformed to the pseudo-second-order kinetic model. Thermodynamic quantities such as Gibbs free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) were evaluated and the negative values of ΔG0, ΔH0 and ΔS0 obtained indicated the spontaneous and exothermic nature of the MG adsorption process while positive enthalpy (ΔH0) indicated an endothermic nature of CR adsorption process.


Author(s):  
Ebuka Leonard Onyeyilim ◽  
Mercy Amarachi Ezeokonkwo ◽  
Chiamaka Peace Uzoewulu ◽  
Florence Uchenna Eze ◽  
Festus Chinonso Urama ◽  
...  

In this manuscript, the authors explore the antimicrobial and anti-inflammatory properties of extracts from two commonly found and used leaves from species Murraya koenigii and Ocimum gratissimum L., Ethanolic extracts were obtained by maceration and were then concentrated. Serial dilutions of the extracts were done for testing. The extracts were tested for growth inhibition of four bacterial and two fungal strains. Visual examination of growth inhibition, compared to standard antibiotic controls, provided minimum inhibitory concentrations for the two extracts against the six microbial strains. In another experiment, the authors test the anti-inflammatory properties of the two leaf extracts in the standard rat-paw model of inflammation. Results from growth inhibition studies suggest that the two leaf extracts inhibit the growth of all six microbes, with varying levels of sensitivity. Results from anti-inflammatory studies are more impressive, with leaf extracts inhibiting inflammation at levels competitive with the standard drug, indomethacin.


Author(s):  
Seplapatty Kalimuthu Periyasamy ◽  
R. Ponmadasamy

Oxidation of dibenzalacetone with pyrazinium chlorochromate in presence of oxalic acid has been studied at 313 K. Various reaction parameters such as effect of varying oxidant, substrate, Hydrogen ion concentration, catalyst, solvent composition, ionic strength, effect of Mn2+, effect of Al3+ and effect of temperature were studied to determine the kinetics of the reaction. Our study revealed that the reaction followed first order dependence with respect to oxidant and catalyst. The reaction followed fractional order kinetics with respect to substrate and H+. Increase in ionic strength was found to have no effect on the reaction rate and decrease in the dielectric constant of the medium decreases the reaction rate. Increase in the concentration of manganous sulphate retarded the reaction rate which confirmed the two-electron transfer involved in the mechanism. There was no possibility of free radical mechanism, which was confirmed by the addition of acrylonitrile shows no significant effect on the reaction rate indicating the non-involvement of free radical reaction.. Based on the experimental observations a mechanism and rate law has been derived. Moreover, the oxidation product was found to be chalcone epoxide, which was characterized by IR spectrum.


Author(s):  
Bjorn Jasper R. Raquel ◽  
Agnes C. Bantaculo ◽  
Shane Carlo B. Llemit ◽  
Eldrin P. Custodio

This paper presents the spectroscopic graphs of recently discovered Supernova Remnants (AT2019fya, SN2019fjp, SN2019fcc, SN2019fce, SN2019fbv & SN2019ffi) for the determination of elements present. The researchers use the spectral plot analysis to analyze the presence of certain elements of the individual supernova remnants (SNR) for the assimilation, differentiation and classification of these SNR. Redshift and velocities of these SNR were also found using the observed wavelength and the rest wavelength ratio. Comparison suggests that AT2019fya is a Type II supernova remnant and some of the SNRs in this study exhibits an existence of krypton (Kr) on their composition which is recently discovered by M. Barlow (2013) to be present at the Crab Nebula. This might suggest that AT2019fya, SN2019fbv, SN2019fce, and SN2019ffi have a pulsar at their center.


Author(s):  
Dayena J. Christian ◽  
Rajesh H. Vekariya ◽  
Kinjal D. Patel ◽  
Dhanji P. Rajani ◽  
Smita D. Rajani ◽  
...  

A data set of chalcone and pyrimidine derivatives with anti-malarial activity against Plasmodium falciparum was employed in investigating the quantitative structure-activity relationship (QSAR). Molecular docking study was performed for plasmodium falciparum dihydrofolate reductase (PfDHFR-TS). Genetic function approximation (GFA) technique was used to identify the descriptors that have influence on anti-malarial activity. The most influencing molecular descriptors identified include thermodynamics, structural and physical descriptors. Generated model was found to be good based on correlation coefficient, LOF, rm2 and rcv2 values. Nrotb, solubility, polarizibility may have negative influence on antimalarial activity or play an important role in growth inhibition of Plasmodium falciparum. The QSAR models so constructed provide fruitful insights for the future development of anti-malarial agents.


Author(s):  
Shipra Baluja ◽  
Mona Pithiya ◽  
Asmita Hirapara ◽  
Divyata Lava

The solubility of triazolo quinolone class derivatives in methanol, ethanol, n-propanol, n-butanol and ethyl acetate was measured using a gravimetrical method at temperature ranging from 298.15 K to 328.15 K. The results of these measurements were correlated with semi empirical equations. Some thermodynamic parameters such as dissolution enthalpy, Gibb’s free energy and entropy of mixing have also been calculated.


Author(s):  
Sergey G. Fedosin

Within the framework of the theory of relativistic vector fields, the covariant expressions are presented for the equations of motion of the matter and the field. These expressions can be written either in terms of the field tensors, that is, the fields’ strengths and solenoidal vectors, or in terms the four-potentials, that is, the fields’ scalar and vector potentials. This state of things is due to the fact that the Lagrange function initially implied the complementarity of description in terms of the strengths and the field potentials. It is shown that the equation for the fields, obtained by taking the covariant derivative in the equation for the metric, has a deeper meaning than the ordinary equation of motion of the matter, found with the help of the principle of least action. In particular, the above-mentioned equation for the fields leads to the generalized Poynting theorem, and after integration over the volume it allows us to introduce for consideration the integral vector as a measure of the energy and the fields’ energy fluxes, associated with a system of particles and fields.


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