5,063 research outputs found

    The organization of 2,3-iron-naphthalocyanine molecules on substrate as revealed by scanning tunneling microscopy

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    Surface morphology of thin molecular layer of 2,3-Iron-naphthalocyanine (2,3 FeNPc) was studied by scanning tunneling microscopy (STM) at the ambient conditions. Organic layer with thickness of 40 nm was vapour phase deposited on amorphous carbon substrate. The STM images have revealed the pecularities of surface molecular organization from large range (hundreds of nm) down to atomic scale. Arrays of locally ordered linear stuctures have been distinguished as the main morphological features of the examined surface. At several places the well-ordered STM patterns have been distinguished at the atomic scale. They can be described as stacks of periodicity approximatelly 0.4 nm in a row and 1.5 nm between stacks. These results can be explained by arrangement of 2,3-FeNPh molecules in stacks with a main plane being perpendicular to the substrate surface

    Exotic quark effects on the Higgs sector of the USSM at the LHC

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    The Higgs sector of the U(1)-extended supersymmetric model is studied with great detail. We calculate the masses of the Higgs bosons at the one-loop level. We also calculate at the one-loop level the gluon-involving processes for the productions and decays of the scalar Higgs bosons of the model at the energy of the CERN Large Hadron Collider (LHC), where the radiative corrections due to the loops of top, bottom, and exotic quarks and their scalar partners are taken into account. We find that the exotic quark and exotic scalar quarks in the model may manifest themselves at the LHC, since the production of the heaviest scalar Higgs boson via gluon fusion processes is mediated virtually by the loops of exotic quark and exotic scalar quarks, for a reasonable parameter set of the model.Comment: 36 pages, 13 figures, JP

    Explosive Ballooning Flux Tubes in Tokamaks

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    Tokamak stability to, potentially explosive, `ballooning' displacements of elliptical magnetic flux tubes is examined in large aspect ratio equilibrium. Above a critical pressure gradient the energy stored in the plasma may be lowered by finite (but not infinitesimal) displacements of such tubes (metastability). Above a higher pressure gradient, the linear stability boundary, such tubes are linearly and nonlinearly unstable. The flux tube displacement can be of the order of the pressure gradient scale length. Plasma transport from displaced flux tubes may result in rapid loss of confinement.Comment: 4 pages, 6 figure

    Nonlinear Stability and Saturation of Ballooning Modes in Tokamaks

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    The theory of tokamak stability to nonlinear "ballooning" displacements of elliptical magnetic flux tubes is presented. Above a critical pressure profile the energy stored in the plasma may be lowered by finite (but not infinitesimal) displacements of such tubes (metastability). Above a higher pressure profile, the linear stability boundary, such tubes are linearly and nonlinearly unstable. The predicted saturated flux tube displacement can be of the order of the pressure gradient scale length. Plasma transport from these displaced flux tubes may explain the rapid loss of confinement in some experiments

    Experimental and theoretical study of three interacting, closely-spaced, sharp-edged 60 deg delta wings at low speeds

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    Wind tunnel tests were conducted to determine the subsonic longitudinal aerodynamic characteristics of lifting configuration consisting of a 60 deg delta main wing with two smaller 60 deg delta wings (called sub-wings) attached underneath. The test was designed to determine the effects on lift, drag, and pitching moment due to various placement of the subwings in relation to the main wing. Test results indicate the increasing vertical separation between the main wing and the sub-wings produced the most significant results; a 23.1% increase in maximum lift coefficient, a reduction in drag coefficient at high lift coefficients, and an increase in longitudinal stability. Lateral separation of the sub-wings produced no significant changes. Placement of the sub-wings rearward increases the initial lift curve slope and maximum lift coefficient and also increase the longitudinal stability. Results of a computer study using a vortex lattice code supported the experimental conclusions

    Spontaneous Violation of the CP Symmetry in the Higgs Sector of the Next-to-Minimal Supersymmetric Model

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    The spontaneous violation of the CP symmetry in the next-to-minimal supersymmetric standard Model (NMSSM) is investigated. It is found that the spontaneous violation of the CP symmetry can occur in the Higgs sector of the NMSSM for a wide region of the parameter space of the model, at the 1-loop level where the radiative corrections due to the top quark and scalar-top quark loops are found to generate the scalar-pseudoscalar mixings between the two Higgs doublets of the NMSSM. In our model, we assume that the masses of the left-handed and the right-handed scalar-top quarks are not degenerate. And we investigate our model anaytically: We derive analytical formulae of the 1-loop mass matrix for the neutral Higgs bosons. We calculate the upper bound on the lightest neutral Higgs boson mass under the assumption. It is found to be about 140 GeV for our choice of parameter values in the presence of the spontaneous violation of the CP symmetry in the NMSSM. Thus, the possibility of the spontaneous violation of the CP symmetry is not completely ruled out in the Higgs sector of the NMSSM if the masses of the left-handed and the right-handed scalar-top quarks are not degenerate. Further, the phenomenology of the KK-Kˉ{\bar K} mixing within the context of our model is studied. The lower bound on CP violating phase in the KK-Kˉ{\bar K} mixing is found to increase if either tanβ\tan\beta decreases or AtA_t increases.Comment: 21 pages, 5 figures, To appear in Phys. Rev.

    Інвестиційне кредитування переробних підприємств АПК банківськими установами

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    Метою статті є аналіз динаміки інвестиційного кредитування банківськими установами переробних підприємств агропромислового комплексу. Під час проведення дослідження були використані аналітичний, статистико – економічний, графічний, порівняльний методи та метод системного аналізу

    Psychometric Assessment of the Comprehensive Effects of Alcohol Questionnaire: Comparing a Brief Version to the Original Full Scale

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    The current set of studies compared the psychometric properties of the original Comprehensive Effects of Alcohol Questionnaire (CEOA) to a 15-item version (B-CEOA) in a nonclinical undergraduate sample (N = 581), and attempted to replicate and extend the B-CEOA findings in an undergraduate sample referred to an alcohol intervention (N = 734). Psychometric assessment included construct validity, internal consistency, and concurrent validity, using both “positive” and “negative” expectancy items in all analyses. Results provided further support for the empirical validity of the original CEOA, and provided support for the use of the B-CEOA despite the reduction in the number of items. The B-CEOA factor structures obtained using exploratory and confirmatory techniques provided support for a 4-factor structure of expectancies and 3-factor structure of valuations. Findings reveal potential problems with “positive” and “negative” expectancy items. Trade-offs regarding factor structure, internal consistency, and administration time should be considered in using the B-CEOA vs. the CEOA
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