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GLOBAL REGULAR SOLUTION FOR THE EINSTEIN-MAXWELL-BOLTZMANN-SCALAR FIELD SYSTEM IN A BIANCHI TYPE-I SPACE-TIME
Get PDFWe prove an existence and uniqueness of regular solution to the Einstein-Maxwell-Boltzmann-Scalar Field system with pseudo-tensor of pressure and the cosmological constant globaly in time. We clarify the choice of the function spaces and we establish step by step all the essential energy estimations leading to the global existence theorem
Generalized (; )-derivations and Left Ideals in Prime and Semiprime Rings
Get PDFLet R be an associative ring, ; be the automorphisms of R, be a nonzero left ideal of R, F : R ! R be a generalized (; )-derivation and d : R ! Rbe an (; )-derivation. In the present paper we discuss the following situations: (i) F(xoy) = a(xy yx), (ii) F([x; y]) = a(xy yx), (iii) d(x)od(y) = a(xy yx) forall x; y 2 and a 2 f0; 1;ô€€€1g. Also some related results have been obtained
A CRITICAL REVIEW ON POLYURETHANE POLYMER HYBRID NANO COMPOSITES
Get PDFCritical review on polyurethane hybrid nano composite paper gives knowledge on its techniques and their applications. In addition to the scientific framework for the advancement in the polymer matrix hybrid nano composite research, the critical review provides an ample discussion on technology, characterization, processing and its applications on polyurethane hybrid nano composites
IMPACT OF PRESSURE ON THE PERFORMANCE OF PROTON EXCHANGE MEMBRANE FUEL CELL
Get PDFThe Proton Exchange Membrane (PEM) fuel cell performance not only depends on temperature but also depends on the operating pressure, which will increase the performance of the PEM fuel cell. The PEM fuel cell with serpentine flow field was modeled using Solidworks software and analyzed using ANSYS software. By analysis of three different pressures on the PEM fuel cell, and came to know that the optimum pressure gives the best performance. The peak power density occurs in the constant temperature of 323 K with the pressure of 2 bar
HYDROGEOCHEMICAL QUALITY OF GROUNDWATER IN PERUMAL LAKE, KURINJIPADI TALUK, CUDDALORE DISTRICT, TAMILNADU, INDIA
Get PDFA study was carried out to determine the groundwater quality in parts of Perumal Lake, Kurinjipadi Taluk, Cuddalore district, Tamilnadu. Totally, 12 groundwater samples were collected at different parts of study area and 16 water samples from surface reservoirs (Perumal lake) and analyzed for physicochemical parameters (pH, EC, TDS, TH, Na, K, Ca, Mg and Cl, SO4 , HCO3- , NO3 ) in order to understand the hydro geochemistry of the water. The results of analysis were interpreted with geology and geomorphology of the area and also by various geochemical diagrams such as Piper trilinear plot and USSL classification diagram. Suitability of this water for its utility was verified using Indian standards. The result indicates irrespective of the seasons that only one well is suitable for drinking purpose, with remaining suitable for domestic and irrigation purpose. Further, from the results, it is pointed out that most of the well water falls in Na-Cl type indicating the influence of seawater in these wells which was confirmed by Piper plot. According to SAR (alkali hazard) and specific conductance (Salinity hazard) is plotted in USSL diagram, classification of water for irrigation purpose can be determined. Majority of groundwater samples fall in C3S1 zone indicating high salinity and low sodium hazard, satisfactory for plants having moderate salt tolerance on soils. In surface water most of the samples fall in C2S1 indicates medium salinity and low sodium hazard
Dual Watermarking in Cyber Security
Get PDFCyber security is generally a conservatory of the conventional information system security that is aimed at protecting cyber threats, like cyber terrorism, cyber warfare, and cyber espionage to corrupt digital information. This leads to increase the researches in cyber security. This paper proposes the application of dual watermarking in cyber technology, focusing on forgery detection. The rest of the paper presents a brief overview of cyber security and the role of digital dual watermarking. 
Synthesis, Spectral Characterization and Antibacterial Investigation of Ni(II) Coordination Complexes of Macrocyclic Schiff base ligands Derived from 4-Aminoantipyrine
Get PDFA series of Ni(II) complexes (NiL1-NiL5) have been synthesized from macrocyclic Schiff base ligands (L1-L5) were obtained from condensation of 4-aminoantipyrine derivative (L) with different diamines and hydrazides. All these compounds were well characterized by elemental, spectral analysis(mass, IR, 1H-NMR, electronic), magnetic suseceptibility, molar conductance and thermal studies. Macrocyclic Schiff bases are tetradentate with N4 donor system around the metal ion.Octahedral geometry have been assigned for all complexes. All ligands and complexes were examined for antibacterial activity and found that complexes were more potent when compared to ligands.  
Investigation of the Effect of Natural Extract on Corrosion Behavior of Tin in Na2CO3 Solution
Get PDFThe inhibition effect of eugenol oil (EO) on the corrosion of tin in 0.1 M Na2CO3 has been studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technics. The effect of temperature on the corrosion behavior of tin in 0.1 M Na2CO3 with and without addition of eugenol oil was studied in the temperature range 278-308 K. This compound inhibits the corrosion of tin at low concentration. At 4g/L eugenol oil the inhibition efficiency calculated by potentiodynamic polarization and EIS techniques is 70% and 82%, respectively. The inhibition efficiency increased with increase of the inhibitor concentration and decreased with increase of medium temperature. Electrochemical impedance spectroscopy was used to investigate the mechanism of corrosion inhibition. Polarization curves reveal that EO acts as a mixed-type inhibitor in corrosive solution. The results obtained from the different corrosion evaluation techniques are in good agreement
New structure induced by elastic anisotropy in cylindrical nematic liquid crystal
Get PDFBasing on Landaude Gennes theory, this study investigated the chiral configurations of nematic liquid crystals confined to cylindrical capillaries with homeotropic anchoring on the cylinder walls. When the elastic anisotropy (L2/L1) is large enough, a new structure results from the convergence of two opposite escape directions of the heterochiral twist and escape radial (TER) configurations. The new defect presents when L2/L17 and disappears when L2/L1<7. The new structure possesses a heterochiral hyperbolic defect at the center and two homochiral radial defects on both sides. The two radial defects show different chiralities
The Solar Neutrino Problem Has Not Been Solved
Get PDFA closer look at the data collected from different detectors, reveal that the so-called solar neutrino problem is far from being solved. And contrary to the assessment of the Nobel Committee, the experimental results from the Sudbury Neutrino Observatory cannot be a confirmation of the Standard Solar Model. In fact, the obsoleteness of the current model has been recently exposed by the crisis of solar abundance. Furthermore, using images obtained by the Solar Dynamics Observatory, researchers found the convective motions (the plasma motions at the Sun's interior) to be nearly 100 times smaller than current theoretical expectations