483 research outputs found

    Energy dissipation and scattering angle distribution analysis of the classical trajectory calculations of methane scattering from a Ni(111) surface

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    We present classical trajectory calculations of the rotational vibrational scattering of a non-rigid methane molecule from a Ni(111) surface. Energy dissipation and scattering angles have been studied as a function of the translational kinetic energy, the incidence angle, the (rotational) nozzle temperature, and the surface temperature. Scattering angles are somewhat towards the surface for the incidence angles of 30, 45, and 60 degree at a translational energy of 96 kJ/mol. Energy loss is primarily from the normal component of the translational energy. It is transfered for somewhat more than half to the surface and the rest is transfered mostly to rotational motion. The spread in the change of translational energy has a basis in the spread of the transfer to rotational energy, and can be enhanced by raising of the surface temperature through the transfer process to the surface motion.Comment: 8 pages REVTeX, 5 figures (eps

    3-Phase gate-turn off thyristor inverter

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    Bibliography: 140-146.The requirements of a standard 3-phase Induction Motor driven by a Voltage Source Inverter (VSI) are studied. A full 3-phase Variable Speed Drive (VSD) and its controller have been designed, constructed and tested. Gate Turn-Off Thyristors (GTO's) are used as the main switching elements in the Inverter stage of the Drive. The drive requirements of GTO's are studied in detail

    The performance of serial correlation preliminary test estimators under asymmetry loss functions

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    The risk performances, under the symmetric squared error loss function, of the estimators of the regression coefficients after a preliminary test for serial correlation have been widely investigated in the literature. However, it is well known that the use of the symmetric loss functions is inappropriate in estimation problems where underestimation and overestimation have different consequences. We consider the Linear Exponential and Bounded Linear Exponential loss functions which allows for asymmetry. The risks of the estimators are derived and numerically evaluated by using simulations

    Divertor conditions relevant for fusion reactors achieved with linear plasma generator

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    Intense magnetized hydrogen and deuterium plasmas have been produced with electron densities up to 3.6¿×¿1020¿m-3 and electron temperatures up to 3.7¿eV with a linear plasma generator. Exposure of a W target has led to average heat and particle flux densities well in excess of 4¿MW m-2 and 1024¿m-2 s-1, respectively. We have shown that the plasma surface interactions are dominated by the incoming ions. The achieved conditions correspond very well to the projected conditions at the divertor strike zones of fusion reactors such as ITER. In addition, the machine has an unprecedented high gas efficiency

    Molecular Modeling, Synthesis, and Antihyperglycemic Activity of the New Benzimidazole Derivatives – Imidazoline Receptor Agonists

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    Artur Martynov,1 Boris Farber,2 Tatyana Bomko,1 Daniel L Beckles,3 Ilya Kleyn4 1Laboratory and Clinical department of Molecular Immunopharmacology, SI “ I. Mechnikov Institute of Microbiology and Immunology of National Academy of Medical Sciences of Ukraine, Kharkiv, Ukraine; 2R&D Department, Noigel LLC, New York, NY, USA; 3Baylor Scott & White Health, Round Rock, TX, USA; 4SUNY Downstate Medical Center / University Hospital of Brooklyn, New York, NY, USACorrespondence: Artur Martynov, Email [email protected]: The paper presents the results of a study on the first synthesized benzimidazole derivatives obtained from labile nature carboxylic acids. The synthesis conditions of these substances were studied, their structure was proved, and some components were found to have sugar-reducing activity on the model of alloxan diabetes in rats.Methods: The study used molecular modeling methods such as docking based on the evolutionary model (igemdock), RP_HPLC method to monitor the synthesis reaction, and 1H NMR and 13C NMR, and other methods of organic chemistry to confirm the structures of synthesized substances.Results & Discussion: The docking showed that the ursodeoxycholic acid benzimidazole derivatives have high tropics to all imidazoline receptor carriers (PDB ID: 2XCG, 2bk3, 3p0c, 1QH4). The ursodeoxycholic acid benzimidazole derivative and arginine and histidine benzimidazole derivatives showed the highest sugar-lowering activity in the experiment on alloxan-diabetic rats. For these derivatives, the difference in glucose levels of treated rats was significant against untreated control. Therefore, the new derivatives of benzimidazole and labile natural organic acids can be used to create new classes of imidazoline receptor inhibitors for the treatment of diabetes mellitus and hypertension.Keywords: imidazoline receptors, benzimidazole derivatives, synthesis, antihyperglycemic activit
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