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Non-Interacting Spin Systems Described by Probabilistic Soft Sets
Get PDFIn this paper we study the system of non-interacting spins like electrons by using notions probability, soft sets and probabilistic soft sets. Electrons are indistinguishable identical particles whose spin is one of their features like mass of electron, charge of electron etc. We also compare two systems of non-interacting spins by defining two soft spin sets and calculating their similarity measure
Thermal and exergy analysis of the use of the lens in parabolic trough.: use of the lens in parabolic trough
No full textThe aim of current study, is looking for a new way to increase the efficiency of the solar collector parabolic trough analytical and experimentally. To do a collector through is produced and equiped with 23 lenses located above the absorber tube in a row. The use of the lens increase the efficiency of Parabolic trough collector up to 14 percent. The system analysed theorically and evaluates by first and second law of thermodynamics. For the estimation of solar radiation the two methods of maximum probability and Prescott's angstrom methods is used, and compared with the data of the pyrometer device (radiation gauge). By the statistical criteria, the Angstrom method is more accurate compared to the maximum probability. Various components of heat transfer is analyzed through the system evolution versus time. The results show that the maximum exergy efficiency of the system was about 52 percent. As well the use of lens enhance the exergy efficiency of the system
The Growth and Characterization of Zinc Silver Sulphide Thin Films Prepared by Chemical Bath Deposition Technique
No full textZinc Silver Sulphide thin films have been successfully prepared by the chemical bath deposition technique. The reaction bath consists of solutions of Zn(COOH)2, AgNO3, CH3CH2NS, TEA and NH3 in 50ml beakers. The films are shiny dark brown in colour and are strongly adhered to the substrates and retain their properties for a long period of time. The films have high absorbance at the UV region and can be used as UV filters. The thin film annealed at 373K has the highest absorbance of 2.7% at the UV region. The thin films have low transmittance in the UV region due to the high absorbance. The film sample annealed at 423K has the highest transmittance in the visible region (about 80%). These properties make the films suitable for solar window control applications. The XRD studies show that the films are crystalline in nature and the range of the grain size obtained is from 0.752nm to 1.145nm. The band gap obtained is in the range of 1.9eV to 2.45eV which gives it potential application in solar cell fabrication. 
Bare Surfaces Analysis within Ograzhden Mountain (Bulgarian Part)
Get PDFThe presence of bare surfaces is one of the main indicators for the degradation of natural ecosystems. The spread of bare surfaces and respectively the lack of vegetation cover is a serious threat to the sustainable development of complex environments such as mountains. The present study focuses on the spatial-temporal relationships of the bare surfaces with the local environment within the Bulgarian part of the small border mountain of Ograzhden. Based on temporal imageries from the Landsat 8 satellite, an analysis of the spatial distribution and tendencies in the development of bare surfaces has been made over a two-year period of time. Overall, the results of the research show a reduction in the total area of bare surfaces on the one hand and a slow environmental recovery on the other. Unfortunately, the positive changes are not ubiquitous, but describe only certain areas of the territory of interest
Annual Reviewer Acknowledgement
No full textThe Editorial team of the journal would like to thank the following reviewers for their work in refereeing manuscripts during 201
Activation Parameter and Solvent Effect on Solvolysis of Ethyl Benzoate in Aquo-Organic Solvent System.
Get PDFThe rate of hydrolysis of hydrolysis of ethyl benzoate were measured volumetric over the temperature range of 200c to 400c.in water-methanol mixture at different composition. The different solvation in initial and transition state is due to decrease in rate with varying the composition of mixture. The influence of solvent on reaction rate was examined in term of activation parameter. The increase in values of DG* and simultaneous depletion in values of DH* and DS* with solvent composition reveals that the reaction is Enthalpy domination and Entropy controlled. The value of iso-kinetic temperature is less than 300 shows the weak interaction between solvent and solute
Electrostatic Discharge and Energetic Materials
Get PDFIn this short review, excerptions from the literature on electrostatic discharge which includes physics of electric spark, charging of organic molecules, sensitivity measurements, some theory and predictions, and electrostatic discharge values of some group of explosives, including nitro compounds, nitramines, composites thermites, etc., have been presented
Influence of Particle Size on the Anticonvulsant Activity of Propoxazepam
Get PDFThe granulometric composition of new analgesic substance (7-bromo-5-(o-chlorophenyl)-3-propoxy-1,2-dihydro-3H-1,4-benzodiazepin-2-one) was characterized by methods of crystals microscopy and lazer diffraction,. The single polymorphic phase demonstrated by differential scanning calorimetry, X-ray diffraction analysis, Raman and IR-spectroscopy. On the base of the anticonvulsive effect on mice in compare to coarse сcrystalline sample the conclusion about the higher pharmacological effect for the disperse sample had been demonstrated
Theoretical Study of Quinoline Aza Oxa Thia 17-Crown -6 Complexes: NICS Aromaticity
Get PDFComplexation of quinoline aza oxa this 17-crown-6 (L) with some metal cations (K+, Na+, Li+, Mg2+) was studied through computational methods. Hartree-Fock method was employed to identify structure and thermodynamical binding constant of crown and metal ions complexes. The calculations were conducted at the HF/6-31g and HF/Lanl2DZ levels of theory. According to the obtained data Mg2+ ion formed the most stable complex with crown and equilibrium binding constants of complex formation has the following order: L. K+ < L. Na+ <L. Li+ <L. Mg2+. In order to verify the physical properties of free crown and complexes some important physical properties including band gap, energy, hardness and dipole moments were obtained and discussed. The electron distribution over the free crown and its L. Mg2+ complex was studied which showed that in the free crown and its L. Mg2+ complex, Highest Occupied Molecular Orbital (HOMO) were distributed mainly over the sulfur atom. For both of them Lowest Unoccupied Molecular Orbital (LUMO) were distributed over aromatic rings. HOMO and LUMO orbitals in L. Mg2+ complex was not distributed over Mg2+ ion and the ion remained bare. Also, atomic charges and charge transfer between donors and acceptors were studied using natural bond orbital analysis (NBO). The charge of Mg2+ ion in the complex is 1.69095 e. In order to study the effect of complex formation and structural changes on the aromaticity of rings, Nuclear Independence Chemical Shift (NICS) and aromaticity were obtained and discussed
Civil Jurisdiction And Jury Court: Proposals For Improvement In Spain From Comparative Law
Get PDFThe Jury court is a fairly common institution in any of the existing legal systems in the world. There is an important difference between the continental and Anglo-Saxon models, highlighting the main difference the existence of the Jury court in civil litigation, unusual situation in the continental system with exceptions, and in particular in Spain. We will also analyze a hypothetical reform of the Jury in Spain by doing a legal analysis with other States