823 research outputs found

    Faktor-faktor yang Berhubungan dengan Status Gizi Buruk pada Balita di Kota Semarang Tahun 2017 (Studi di Rumah Pemulihan Gizi Banyumanik Kota Semarang)

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    Severe acute malnutrition is a condition where nutritional deficiencies are seen based on nutritional status that is below the average standard determined based on the anthropometric indicator of body weight by height (WHZ)) with z-score <-3 SD and presence or absence of edema. The purpose of this study is to determine the factors associated with malnutrition status in under five child in Nutrition House of Semarang City. The type of research used is descriptive analytic quantitative research with cross sectional method. Population in this research is all mother and child who undergo recovery at Home Nutrition by sampling technique using total sampling technique that is 20. Anthropometric measurements were performed to calculate z-scores, filling out questionnaires, food recalls and food and non-family food expenditure forms. After doing the research, it is known that child suffering from severe acute malnutrition based on indicator WHZ is as many 11 people (55%). The results showed that variables associated with nutrition status were energy consumption level (p = 0,002), protein consumption (p = 0,04), and infectious disease (p = 0,000). While the variables associated with the level of energy and protein consumption is maternal nutrition knowledge and family economic status variables (p = 0.001)

    Vortices on a superconducting nanoshell: phase diagram and dynamics

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    In superconductors, the search for special vortex states such as giant vortices focuses on laterally confined or nanopatterned thin superconducting films, disks, rings, or polygons. We examine the possibility to realize giant vortex states and states with non-uniform vorticity on a superconducting spherical nanoshell, due to the interplay of the topology and the applied magnetic field. We derive the phase diagram and identify where, as a function of the applied magnetic field, the shell thickness and the shell radius, these different vortex phases occur. Moreover, the curved geometry allows these states (or a vortex lattice) to coexist with a Meissner state, on the same curved film. We have examined the dynamics of the decay of giant vortices or states with non-uniform vorticity into a vortex lattice, when the magnetic field is adapted so that a phase boundary is crossed.Comment: 21 pages, 9 figure

    The effect of pressure on statics, dynamics and stability of multielectron bubbles

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    The effect of pressure and negative pressure on the modes of oscillation of a multi-electron bubble in liquid helium is calculated. Already at low pressures of the order of 10-100 mbar, these effects are found to significantly modify the frequencies of oscillation of the bubble. Stabilization of the bubble is shown to occur in the presence of a small negative pressure, which expands the bubble radius. Above a threshold negative pressure, the bubble is unstable.Comment: 4 pages, 2 figures, accepted for publication in Physical Review Letter

    Sonoluminescence and collapse dynamics of multielectron bubbles in helium

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    Multielectron bubbles (MEBs) differ from gas-filled bubbles in that it is the Coulomb repulsion of a nanometer thin layer of electrons that forces the bubble open rather than the pressure of an enclosed gas. We analyze the implosion of MEBs subjected to a pressure step, and find that despite the difference in the underlying processes the collapse dynamics is similar to that of gas-filled bubbles. When the MEB collapses, the electrons inside it undergo strong accelerations, leading to the emission of radiation. This type of sonoluminescence does not involve heating and ionisation of any gas inside the bubble. We investigate the conditions necessary to obtain sonoluminescence from multielectron bubbles and calculate the power spectrum of the emitted radiation.Comment: 6 figure

    Variational Monte Carlo study of the ground state properties and vacancy formation energy of solid para-H2 using a shadow wave function

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    A Shadow Wave Function (SWF) is employed along with Variational Monte Carlo techniques to describe the ground state properties of solid molecular para-hydrogen. The study has been extended to densities below the equilibrium value, to obtain a parameterization of the SWF useful for the description of inhomogeneous phases. We also present an estimate of the vacancy formation energy as a function of the density, and discuss the importance of relaxation effects near the vacant site

    Limits to Sympathetic Evaporative Cooling of a Two-Component Fermi Gas

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    We find a limit cycle in a quasi-equilibrium model of evaporative cooling of a two-component fermion gas. The existence of such a limit cycle represents an obstruction to reaching the quantum ground state evaporatively. We show that evaporatively the \beta\mu ~ 1. We speculate that one may be able to cool an atomic fermi gas further by photoassociating dimers near the bottom of the fermi sea.Comment: Submitted to Phys. Rev

    Adsorption and two-body recombination of atomic hydrogen on 3^3He-4^4He mixture films

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    We present the first systematic measurement of the binding energy EaE_a of hydrogen atoms to the surface of saturated 3^3He-4^4He mixture films. EaE_a is found to decrease almost linearly from 1.14(1) K down to 0.39(1) K, when the population of the ground surface state of 3^3He grows from zero to 6×10146\times10^{14} cm2^{-2}, yielding the value 1.2(1)×10151.2(1)\times 10^{-15} K cm2^2 for the mean-field parameter of H-3^3He interaction in 2D. The experiments were carried out with overall 3^3He concentrations ranging from 0.1 ppm to 5 % as well as with commercial and isotopically purified 4^4He at temperatures 70...400 mK. Measuring by ESR the rate constants KaaK_{aa} and KabK_{ab} for second-order recombination of hydrogen atoms in hyperfine states aa and bb we find the ratio Kab/KaaK_{ab}/K_{aa} to be independent of the 3^3He content and to grow with temperature.Comment: 4 pages, 4 figures, all zipped in a sigle file. Submitted to Phys. Rev. Let

    Solid molecular hydrogen: The Broken Symmetry Phase

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    By performing constant-pressure variable-cell ab initio molecular dynamics simulations we find a quadrupolar orthorhombic structure, of Pca21Pca2_1 symmetry, for the broken symmetry phase (phase II) of solid H2 at T=0 and P =110 - 150 GPa. We present results for the equation of state, lattice parameters and vibronic frequencies, in very good agreement with experimental observations. Anharmonic quantum corrections to the vibrational frequencies are estimated using available data on H2 and D2. We assign the observed modes to specific symmetry representations.Comment: 5 pages (twocolumn), 4 Postscript figures. To appear in Phys. Rev. Let

    Bose-Einstein condensation in a one-dimensional interacting system due to power-law trapping potentials

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    We examine the possibility of Bose-Einstein condensation in one-dimensional interacting Bose gas subjected to confining potentials of the form Vext(x)=V0(x/a)γV_{\rm ext}(x)=V_0(|x|/a)^\gamma, in which γ<2\gamma < 2, by solving the Gross-Pitaevskii equation within the semi-classical two-fluid model. The condensate fraction, chemical potential, ground state energy, and specific heat of the system are calculated for various values of interaction strengths. Our results show that a significant fraction of the particles is in the lowest energy state for finite number of particles at low temperature indicating a phase transition for weakly interacting systems.Comment: LaTeX, 6 pages, 8 figures, uses grafik.sty (included), to be published in Phys. Rev.

    Adsorption of para-Hydrogen on Krypton pre-plated graphite

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    Adsorption of para-Hydrogen on the surface of graphite pre-plated with a single layer of atomic krypton is studied thoretically by means of Path Integral Ground State Monte Carlo simulations. We compute energetics and density profiles of para-hydrogen, and determine the structure of the adsorbed film for various coverages. Results show that there are two thermodynamically stable monolayer phases of para-hydrogen, both solid. One is commensurate with the krypton layer, the other is incommensurate. No evidence is seen of a thermodynamically stable liquid phase, at zero temperature. These results are qualitatively similar to what is seen for for para-hydrogen on bare graphite. Quantum exchanges of hydrogen molecules are suppressed in this system.Comment: 12 pages, 6 figures, to appear in the proceedings of "Advances in Computational Many-Body Physics", Banff, Alberta (Canada), January 13-16 200
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