1,436 research outputs found

    Elastic Behaviour and Phonons in BCC Tantalum

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    Charge Delocalization in Self-Assembled Mixed-Valence Aromatic Cation Radicals

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    The spontaneous assembly of aromatic cation radicals (D+•) with their neutral counterpart (D) affords dimer cation radicals (D2+•). The intermolecular dimeric cation radicals are readily characterized by the appearance of an intervalence charge-resonance transition in the NIR region of their electronic spectra and by ESR spectroscopy. The X-ray crystal structure analysis and DFT calculations of a representative dimer cation radical (i.e., the octamethylbiphenylene dimer cation radical) have established that a hole (or single positive charge) is completely delocalized over both aromatic moieties. The energetics and the geometrical considerations for the formation of dimer cation radicals is deliberated with the aid of a series of cyclophane-like bichromophoric donors with drastically varied interplanar angles between the cofacially arranged aryl moieties. X-ray crystallography of a number of mixed-valence cation radicals derived from monochromophoric benzenoid donors established that they generally assemble in 1D stacks in the solid state. However, the use of polychromophoric intervalence cation radicals, where a single charge is effectively delocalized among all of the chromophores, can lead to higher-order assemblies with potential applications in long-range charge transport. As a proof of concept, we show that a single charge in the cation radical of a triptycene derivative is evenly distributed on all three benzenoid rings and this triptycene cation radical forms a 2D electronically coupled assembly, as established by X-ray crystallography

    Cohesion, Elastic Constants and Vibrational Mechanics of Fcc Platinum

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    A model in real space has been developed by extending the generalized form of the exponential potential known as extended generalized exponential potential (EGEP) to account for (a) the correct nature of repulsive and attractive components of forces for all the separations in general and that of small separations in particular, (b) the three-body forces such as volume forces in an indirect way in the framework of EGEP through the parameter n, (c) the dielectric screening functions in an alternative and simpler form through the parameter m. The model is employed to compute the cohesive energy, second-order elastic constants and phenon spectra for fcc platinum. The predictions show promising agreement with experimental findings.Author Affiliation: Divesh Verma A. F. School of Engineering and Technology, Dhauj-121 004, Haryana, India M L Verma* and A Verma Department of Physics, GGDSD College, Palwal-121 102, Haryana, India and R P S Rathore Department of Physics, B.M.A.S. Engineering College, Agra-282 002, Uttar Pradesh, India1.A. F. School of Engineering and Technology, Dhauj-121 004, Haryana, India 2.Department of Physics, GGDSD College, Palwal-121 102, Haryana, India 3.Department of Physics, B.M.A.S. Engineering College, Agra-282 002, Uttar Pradesh, Indi

    Servicios meteorológicos y climáticos para los agricultores de la India

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    Dynamical evolution and leading order gravitational wave emission of Riemann-S binaries

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    An approximate strategy for studying the evolution of binary systems of extended objects is introduced. The stars are assumed to be polytropic ellipsoids. The surfaces of constant density maintain their ellipsoidal shape during the time evolution. The equations of hydrodynamics then reduce to a system of ordinary differential equations for the internal velocities, the principal axes of the stars and the orbital parameters. The equations of motion are given within Lagrangian and Hamiltonian formalism. The special case when both stars are axially symmetric fluid configurations is considered. Leading order gravitational radiation reaction is incorporated, where the quasi-static approximation is applied to the internal degrees of freedom of the stars. The influence of the stellar parameters, in particular the influence of the polytropic index nn, on the leading order gravitational waveforms is studied.Comment: 31 pages, 7 figures, typos correcte

    Minimum temperature forecast at Manali, India

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    Northern India is comprised of complex Himalayan mountain ranges having different altitude and orientation. Knowledge of minimum temperature in this region during winter months is very useful for assessing human comfort and natural hazards. In the present study, Perfect Prognostic temperature at one of the stations, Manali, in Pir Panjal range of Himalayas. Firstly, a statistical dynamical model is developed for assessing next day's temperature category, i.e.≤0°C or >0°C. Once the category is known, then temperature forecast model is developed for that category. Statistical dynamical models are developed for winter season, December, January, February and March (DJFM) using multivariate regression analysis. Model is developed with data of DJFM for 12 years (1984-96) and tested with data of DJFM for the year 1996-97. Analysis data from National Center for Environmental Prediction (NCEP), US, station surface and upper air data of three stations of India Meteorological Department (IMD), India and surface data at Manali are used. Four experiments are carried out with four different sets of predictors to evaluate performance of the models with independent data sets. They are: (i) NCEP reanalysis Center for Medium Range Weather Forecasting (NCMRWF) in India, (iii) day 1 forecast with a T80 global spectral model at NCMRWF and (iv) forecasts from the regional mesoscale model MM% day 1 forecast. A comparison of skill is drawn among these four set of experiments. It is found that best prediction for temperature category is made with an accuracy of 71.2% with MM5 day 1 forecast as predictors in temperature category forecast model. Further, temperature forecast model for ≤0°C category selects only station data and shows skill of 62.1% with independent data, whereas, model for >0°C category selected predictor from numerical analysis also. Here MM5 day 1 forecast makes best prediction with 90.0% skill

    Montmorrilonite K10 catalyzed efficient synthesis of some 4'-nitrochalcones and their 1, 3, 5-triaryl-2-pyrazolines and in vitro antimicrobial evaluation

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    An expeditious synthesis of some 4´-nitrochalcones (3a-n) and their subsequent facile one-pot transformation to 1, 3,5-triaryl-2-pyrazolines (4a-n) has been carried out using montmorrilonite K10 via microwave mediated solvent free protocol.An emphasis is given to highlighting the greenness of the processes, and a fair comparison is also provided between differentinorganic solid supports as catalysts. Both conventional as well as non-conventional approaches have been explored bycomparing the reaction conditions and yields. The newly synthesized pyrazolines were studied for their in vitro antimicrobialevaluation against bacterial strains Bacillus pumilus and Escherichia coli and fungal strains Aspergillus niger and Penicilliumchrysogenum. Findings of biological evaluation highlighted 4b, 4e, 4j and 4m as potential new leads in the search of newantimicrobial agents. The structures of newly synthesized compounds have been established on the basis of elemental analysisand spectroscopic studies.Fil: Ameta, K. L.. Faculty Of Arts, Science & Commerce, Mody University Of; IndiaFil: Rathore, Nitu S.. Faculty Of Arts, Science & Commerce, Mody University Of; IndiaFil: Kumari, Maya. Faculty Of Arts, Science & Commerce, Mody University Of; IndiaFil: Khyaliya, Priyanka. University of Science and Technology; IndiaFil: Dangi R. R.. Faculty Of Arts, Science & Commerce, Mody University Of; IndiaFil: Parellada, Eduardo Alberto. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica. Cátedra de Química Orgánica III; Argentina. Universidad Nacional de Santiago del Estero. Instituto de Bionanotecnología del Noa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Bionanotecnología del Noa; ArgentinaFil: Neske, Adriana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica. Cátedra de Química Orgánica III; Argentin

    PROTECCIÓN QUE EL ESTADO MEXICANO DEBE BRINDAR AL ADULTO MAYOR RESPECTO DE SU PATRIMONIO: LOS JUZGADORES DEL ESTADO DE MÉXICO

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    La reforma constitucional de 2011, colocó en el centro del sistema jurídico mexicano a los Derechos Humanos así, el artículo 1° constitucional señala: “Todas las autoridades, en el ámbito de sus competencias, tienen la obligación de promover, respetar, proteger y garantizar los derechos humanos de conformidad con los principios de universalidad, interdependencia, indivisibilidad y progresividad. En consecuencia, el Estado deberá prevenir, investigar, sancionar y reparar las violaciones a los derechos humanos, en los términos que establezca la ley.” Para efectos de que los adultos mayores estén en aptitud de dinamizar sus derechos y estos no queden sólo en el terreno de ideal normativo, el Estado mexicano, como garante de los derechos de los gobernados debe ir adaptando las normas protectoras conforme se presenten cambios sociales. El derecho debe ser tan dinámico como la propia sociedad, la normatividad debe revisarse en forma permanente y el legislador debe de realizar las adecuaciones pertinentes para que los derechos se dinamicen en términos de efectividad. Respecto de la protección del patrimonio de los adultos mayores es una prioridad revisar no sólo la armónica normatividad que ha de aplicar el juzgador, ya que en el diario quehacer jurisdiccional se perciben las más variadas acciones que ejercen fundamentalmente familiares para despojar de sus bienes a los adultos mayores, sin que ellos reciban beneficio directo alguno.La presente tesis muestra a través de su desarrollo el marco jurídico existente en cuanto a la protección del patrimonio del hombre de la tercera edad en el estado de México. En conjunto con la información del párrafo anterior se muestran datos estadísticos acerca de esta rama de la población (las personas de la tercera edad), así como del sistema judicial en materia civil que existe en el estado de México para la protección de sus patrimonio

    Contribution of Berry Polyphenols to the Human Metabolome

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    Diets rich in berries provide health benefits, however, the contribution of berry phytochemicals to the human metabolome is largely unknown. The present study aimed to establish the impact of berry phytochemicals on the human metabolome. A "systematic review strategy" was utilized to characterize the phytochemical composition of the berries most commonly consumed in the USA; (poly)phenols, primarily anthocyanins, comprised the majority of reported plant secondary metabolites. A reference standard library and tandem mass spectrometry (MS/MS) quantitative metabolomics methodology were developed and applied to serum/plasma samples from a blueberry and a strawberry intervention, revealing a diversity of benzoic, cinnamic, phenylacetic, 3-(phenyl)propanoic and hippuric acids, and benzyldehydes. 3-Phenylpropanoic, 2-hydroxybenzoic, and hippuric acid were highly abundant (mean > 1 µM). Few metabolites at concentrations above 100 nM changed significantly in either intervention. Significant intervention effects (P < 0.05) were observed for plasma/serum 2-hydroxybenzoic acid and hippuric acid in the blueberry intervention, and for 3-methoxyphenylacetic acid and 4-hydroxyphenylacetic acid in the strawberry intervention. However, significant within-group effects for change from baseline were prevalent, suggesting that high inter-individual variability precluded significant treatment effects. Berry consumption in general appears to cause a fluctuation in the pools of small molecule metabolites already present at baseline, rather than the appearance of unique berry-derived metabolites, which likely reflects the ubiquitous nature of (poly)phenols in the background diet
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