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Sample records for body centered cubic

  1. Dislocation assisted face-centered-cubic/body-centered-cubic interface mixing during severe plastic deformation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jiabin [College of Electrical Engineering, Zhejiang University, Hangzhou 310027 (China); Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Zhang, Lihui [College of Electrical Engineering, Zhejiang University, Hangzhou 310027 (China); Song, Lunan; Meng, Liang; Zeng, Yuewu [Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Wang, Miao [Department of Physics, Zhejiang University, Hangzhou 310027 (China); Fang, Youtong [College of Electrical Engineering, Zhejiang University, Hangzhou 310027 (China); Ma, Jien, E-mail: majien@zju.edu.cn [College of Electrical Engineering, Zhejiang University, Hangzhou 310027 (China)

    2014-02-15

    Highlights: • Interface diffusion with a width of 2–4 nm was detected in Cu–Cr alloy. • Interface mixing is responsible to more rapid increase of electrical resistivity. -- Abstract: Abundant Cu/Cr interface was produced to study the interfacial diffusion at face-centered-cubic/body-centered-cubic interface during heavy cold drawing. Notable interface diffusion with a width of 2–4 nm at Cu/Cr interface was detected. The appearance of the interdiffusion is well explained by the mechanical mixing mechanism with dislocations gliding through the Cu/Cr interface. The greater inelastic scattering of electrons at the interdiffusion zone was responsible to the more rapid increase of electrical resistivity with the increase of drawing strains.

  2. Growth kinetics of body centered cubic colloidal crystals

    OpenAIRE

    Würth, Mathias; Schwarz, Jürgen; Culis, F.; Leiderer, Paul; Palberg, Thomas

    1995-01-01

    A combination of static light scattering and video microscopy is used to perform high precision measurements on the growth velocity of body centered cubic (bcc) crystals in a metastable colloidal melt of monodisperse, highly charged latex spheres. The crystals nucleate heterogeneously at the walls of a flat flow-through shear cell and solidification proceeds without significant disturbance by homogeneous nucleation. The suspension parameters packing fraction Φ of the spheres and the concentra...

  3. Efficient and Accurate Volume Rendering on Face-Centered and Body-Centered Cubic Grids

    OpenAIRE

    Smed, Karl-Oskar

    2015-01-01

    The body centered cubic grid (BCC) and face centered cubic grid (FCC) offer improved sampling properties when compared to the cartesian grid. Despite this there is little software and hardware support for volume rendering of data stored in one of these grids. This project is a continuation of a project adding support for such grids to the volume rendering engine Voreen. This project has three aims. Firstly, to implement new interpolation methods capable of rendering at interactive frame rates...

  4. The reciprocal relationship of orientation dependence of the dislocation boundaries in body-centered cubic metals and face-centered cubic metals

    International Nuclear Information System (INIS)

    The orientation dependence of deformation microstructure has been investigated in uniaxial deformed body-centered cubic molybdenum by electron backscatter diffraction and transmission electron microscopy. It has been found that the dislocation boundaries in both tensile and compressed molybdenum, similar to that in face-centered cubic metals, can be classified into three types: dislocation cells (Type 2), and extended planar boundaries parallel to (Type 1) or not parallel to (Type 3) a {110} trace. Furthermore, it shows a reciprocal relationship between body-centered cubic metals and face-centered cubic metals on the orientation dependence of the deformation microstructure. Type 3 grains have stress axes direction which is near the [110] corner in the unit triangle for BCC metals, whereas Type 3 grains have stress axes direction which is near the [111] corner for FCC metals. The analysis of Schmid factors shows that the dislocation structure depends on the slip systems

  5. The reciprocal relationship of orientation dependence of the dislocation boundaries in body-centered cubic metals and face-centered cubic metals

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shan [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Chen, Chang, E-mail: chench011-33@163.com [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); School of Metallurgy and Environment, Central South University, Changsha 410083 (China); Jia, Yanlin [School of Metallurgy and Environment, Central South University, Changsha 410083 (China); Wang, Mingpu; Xia, Fuzhong; Li, Zhou [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Wang, Zhixing [School of Metallurgy and Environment, Central South University, Changsha 410083 (China)

    2014-12-01

    The orientation dependence of deformation microstructure has been investigated in uniaxial deformed body-centered cubic molybdenum by electron backscatter diffraction and transmission electron microscopy. It has been found that the dislocation boundaries in both tensile and compressed molybdenum, similar to that in face-centered cubic metals, can be classified into three types: dislocation cells (Type 2), and extended planar boundaries parallel to (Type 1) or not parallel to (Type 3) a {110} trace. Furthermore, it shows a reciprocal relationship between body-centered cubic metals and face-centered cubic metals on the orientation dependence of the deformation microstructure. Type 3 grains have stress axes direction which is near the [110] corner in the unit triangle for BCC metals, whereas Type 3 grains have stress axes direction which is near the [111] corner for FCC metals. The analysis of Schmid factors shows that the dislocation structure depends on the slip systems.

  6. Thermo-physical properties of body-centered cubic iron-magnesium alloys under extreme conditions

    OpenAIRE

    Kádas, K.; Ahuja, R.; Johansson, B; Eriksson, O.; Vitos, L.

    2011-01-01

    Using density functional theory formulated within the framework of the exact muffin-tin orbitals method, we investigate the thermo-physical properties of body-centered cubic (bcc) iron-magnesium alloys, containing 5 and 10 atomic % Mg, under extreme conditions, at high pressure and high temperature. The temperature effect is taken into account via the Fermi-Dirac distribution of the electrons. We find that at high pressures pure bcc iron is dynamically unstable at any temperature, having a ne...

  7. Maximal independent set graph partitions for representations of body-centered cubic lattices

    DEFF Research Database (Denmark)

    Erleben, Kenny

    A maximal independent set graph data structure for a body-centered cubic lattice is presented. Refinement and coarsening operations are defined in terms of set-operations resulting in robust and easy implementation compared to a quad-tree-based implementation. The graph only stores information co...... corresponding to the leaves of a quad-tree thus has a smaller memory foot-print. The adjacency information in the graph relieves one from going up and down the quad-tree when searching for neighbors. This results in constant time complexities for refinement and coarsening operations....

  8. Mixed structural face-centered cubic and body-centered cubic orders in near stoichiometric Fe2MnGa alloys

    Science.gov (United States)

    Kudryavtsev, Y. V.; Perekos, A. E.; Uvarov, N. V.; Kolchiba, M. R.; Synoradzki, K.; Dubowik, J.

    2016-05-01

    Magnetic and transport properties of near stoichiometric metastable FexMnyGaz alloys (46 ≤ x ≤ 52, 17 ≤ y ≤ 25, 26 ≤ z ≤ 30) with face-centered cubic (FCC), body-centered cubic (BCC), and two-phase (FCC + BCC) structures are investigated. The experimental results are analyzed in terms of first-principles calculations of stoichiometric Fe2MnGa alloy with the L21, L12, and the tetragonally distorted L21 structural orderings. It is shown that the pure BCC and FCC phases have distinct magnetic and transport properties. Two-phase Fe2MnGa alloys have magnetic and transport properties typical of the mixed BCC and FCC phases. Among the investigated alloys, Fe46Mn24Ga30 has a martensitic transformation accompanied with significant changes of its magnetic and transport properties.

  9. Migration energy barriers of symmetric tilt grain boundaries in body-centered cubic metal Fe

    International Nuclear Information System (INIS)

    Graphical abstract: DFT calculated migration energy barrier (left) for symmetric grain boundary in metals is an essential physical property to measure the trend of grain boundary migration, in particular, in terms of the classical homogeneous nucleation model of GB dislocation/disconnection loops (right). - Migration energy barriers of two symmetric tilt grain boundaries in body-centered cubic metal Fe are obtained via first-principles calculations in combination with the nudged elastic band methods. Although the two grain boundaries show similar grain boundary energies, the migration energy barriers are different. Based on a homogeneous nucleation theory of grain-boundary dislocation loops, the calculated energy barrier provides a measure of intrinsic grain-boundary mobility and helps to evaluate effects due to vacancy and interstitial atoms such as carbon

  10. Rotation-limited growth of three-dimensional body-centered-cubic crystals.

    Science.gov (United States)

    Tarp, Jens M; Mathiesen, Joachim

    2015-07-01

    According to classical grain growth laws, grain growth is driven by the minimization of surface energy and will continue until a single grain prevails. These laws do not take into account the lattice anisotropy and the details of the microscopic rearrangement of mass between grains. Here we consider coarsening of body-centered-cubic polycrystalline materials in three dimensions using the phase field crystal model. We observe, as a function of the quenching depth, a crossover between a state where grain rotation halts and the growth stagnates and a state where grains coarsen rapidly by coalescence through rotation and alignment of the lattices of neighboring grains. We show that the grain rotation per volume change of a grain follows a power law with an exponent of -1.25. The scaling exponent is consistent with theoretical considerations based on the conservation of dislocations. PMID:26274188

  11. A popular metastable omega phase in body-centered cubic steels

    International Nuclear Information System (INIS)

    Steel remains to be one of the most common structural materials in the world as human civilization advances from the Iron Age to the ongoing Silicon Age. Our knowledge of its microstructure evolution and structure–performance relationship is nevertheless still incomplete. We report the observation and characterization of a long ignored metastable phase formed in steels with body-centered cubic (bcc) structure using both transmission electron microscopy and density functional theory calculations. This ω phase has a hexagonal structure and coherent interface with the matrix: aω = √2 × abcc and cω = √3/2 × abcc. It is 3.6% smaller in volume and 0.18 eV higher in energy than bcc-Fe, with atoms in alternating close- and loose-packed layers couple anti-ferromagnetically. Carbon plays a crucial role in promoting bcc to ω transformation. At a concentration higher than 4 at.% they tend to segregate from the bcc matrix to the ω-phase; at about 14 at.%, they can induce bcc to ω transformation; and finally at 25 at.%, they stabilize the ω phase as ω-Fe3C. The ω phase in bcc Fe can serve as sinks for vacancies, H, and He atoms, leading to improved resistance of martensitic steels to irradiation damage. - Highlights: ► A long-ignored metastable ω phase in body-centered cubic (bcc) steel. ► The ω phase has hexagonal structure with lattice parameters aω = √2 × abcc and cω = √3/2 × abcc. ► Carbon enrichment is found to play a crucial role on the bcc-to-ω phase transformation. ► The ω phase is strongly related to the martensitic transformation and twinning structure. ► The ω phase in bcc Fe can serve as sinks for vacancies, H, and He atoms

  12. Grain-boundary strengthening in nanocrystalline chromium and the Hall–Petch coefficient of body-centered cubic metals

    International Nuclear Information System (INIS)

    Nanocrystalline Cr (nc-Cr) was synthesized by electrodeposition. Samples with various grain sizes (19–57 nm) were prepared by annealing the as-deposited sample. Microstructures were examined using X-ray and electron microscopy, and the mechanical properties were evaluated using nanoindentation. The strength of nc-Cr samples apparently obeyed the classical Hall–Petch relationship. It was found that hardening potency caused by grain refinement was generally higher in body-centered cubic metals than that in face-centered cubic and hexagonal close-packed metals. A possible explanation was offered.

  13. The effect of voids on the hardening of body-centered cubic Fe

    Science.gov (United States)

    Nakai, Ryosuke; Yabuuchi, Kiyohiro; Nogami, Shuhei; Hasegawa, Akira

    2016-04-01

    The mechanical properties of metals are affected by various types of defects. Hardening is usually described through the interaction between dislocations and obstacles, in the so-called line tension theory. The strength factor in the line tension theory represents the resistance of a defect against the dislocation motion. In order to understand hardening from the viewpoint of the microstructure, an accurate determination of the strength factor of different types of defects is essential. In the present study, the strength factor of voids in body-centered cubic (BCC) Fe was investigated by two different approaches: one based on the Orowan equation to link the measured hardness with the average size and density of voids, and the other involving direct observation of the interaction between dislocations and voids by transmission electron microscope (TEM). The strength factor of voids induced by ion irradiation estimated by the Orowan equation was 0.6, whereas the strength factor estimated by the direct TEM approach was 0.8. The difference in the strength factors measured by the two approaches is due to the positional relationship between dislocations and voids: the central region of a void is stronger than the tip. Moreover, the gliding plane and the direction of dislocation may also affect the strength factor of voids. This study determined the strength factor of voids in BCC Fe accurately, and suggested that the contribution of voids to the irradiation hardening is larger than that of dislocation loops and Cu-rich precipitates.

  14. Atomistically informed crystal plasticity model for body-centered cubic iron

    International Nuclear Information System (INIS)

    The glide of screw dislocations with non-planar dislocation cores dominates the plastic deformation behavior in body-centered cubic iron. This yields a strong strain rate and temperature dependence of the flow stress, the breakdown of Schmid’s law and a dependence of dislocation mobility on stress components that do not contribute to the mechanical driving force of dislocation glide. We developed a constitutive plasticity model that takes all these effects into account. The model is based on the crystal plasticity approach and parameterized by performing molecular statics calculations using a semi-empirical potential. The atomistic studies yield quantitative relations between local stress tensor components and the mobility of dislocations. Together with experimental stress–strain curves obtained for two different orientations of iron single crystals taken from the literature, the constitutive law is completely parameterized. The model is validated by comparing numerical single crystal tension tests for a third orientation to the equivalent experimental data from the literature. We also provide results for the temperature and strain rate dependence of the new atomistically informed constitutive model.

  15. Bond-order potential for magnetic body-centered-cubic iron and its transferability

    Science.gov (United States)

    Lin, Yi-Shen; Mrovec, M.; Vitek, V.

    2016-06-01

    We derived and thoroughly tested a bond-order potential (BOP) for body-centered-cubic (bcc) magnetic iron that can be employed in atomistic calculations of a broad variety of crystal defects that control structural, mechanical, and thermodynamic properties of this technologically important metal. The constructed BOP reflects correctly the mixed nearly free electron and covalent bonding arising from the partially filled d band as well as the ferromagnetism that is actually responsible for the stability of the bcc structure of iron at low temperatures. The covalent part of the cohesive energy is determined within the tight-binding bond model with the Green's function of the Schrödinger equation determined using the method of continued fractions terminated at a sufficient level of the moments of the density of states. This makes the BOP an O (N ) method usable for very large numbers of particles. Only d d bonds are included explicitly, but the effect of s electrons on the covalent energy is included via their screening of the corresponding d d bonds. The magnetic part of the cohesive energy is included using the Stoner model of itinerant magnetism. The repulsive part of the cohesive energy is represented, as in any tight-binding scheme, by an empirical formula. Its functional form is physically justified by studies of the repulsion in face-centered-cubic (fcc) solid argon under very high pressure where the repulsion originates from overlapping s and p closed-shell electrons just as it does from closed-shell s electrons in transition metals squeezed into the ion core under the influence of the large covalent d bonding. Testing of the transferability of the developed BOP to environments significantly different from those of the ideal bcc lattice was carried out by studying crystal structures and magnetic states alternative to the ferromagnetic bcc lattice, vacancies, divacancies, self-interstitial atoms (SIAs), paths continuously transforming the bcc structure to

  16. Strain field of interstitial hydrogen atom in body-centered cubic iron and its effect on hydrogen-dislocation interaction

    OpenAIRE

    Wang, Shuai; Takahashi, Keisuke; Hashimoto, Naoyuki; Isobe, Shigehito; Ohnuki, Somei

    2013-01-01

    Effect of hydrogen in body-centered cubic iron is explored by using the density function theory. Hydrogen atoms increase the concentration of free electrons in the simulation cell and have bonding interaction with Fe atom. Caused by anisotropic strain components of hydrogen atoms in the tetrahedral sites, elastic interaction for hydrogen with screw dislocation has been found. The dependence of hydrogen-screw dislocation interaction on hydrogen concentration is confirmed by repeated stress rel...

  17. Clean Grain Boundary Found in C14/Body-Center-Cubic Multi-Phase Metal Hydride Alloys

    Directory of Open Access Journals (Sweden)

    Hao-Ting Shen

    2016-06-01

    Full Text Available The grain boundaries of three Laves phase-related body-center-cubic (bcc solid-solution, metal hydride (MH alloys with different phase abundances were closely examined by scanning electron microscopy (SEM, transmission electron microscopy (TEM, and more importantly, electron backscatter diffraction (EBSD techniques. By using EBSD, we were able to identify the alignment of the crystallographic orientations of the three major phases in the alloys (C14, bcc, and B2 structures. This finding confirms the presence of crystallographically sharp interfaces between neighboring phases, which is a basic assumption for synergetic effects in a multi-phase MH system.

  18. A dislocation dynamics study of the transition from homogeneous to heterogeneous deformation in irradiated body-centered cubic iron

    International Nuclear Information System (INIS)

    Low temperature irradiation of crystalline materials is known to result in hardening and loss of ductility, which limits the usefulness of candidate materials in harsh nuclear environments. In body-centered cubic (bcc) metals, this mechanical property degradation is caused by the interaction of in-grown dislocations with irradiation defects, particularly small dislocation loops resulting from the microstructural evolution of displacement cascades. In this paper, we perform dislocation dynamics simulations of bcc Fe containing various concentrations of dislocation loops produced by irradiation in an attempt to gain insight into the processes that lead to hardening and embrittlement. We find that a transition from homogenous to highly localized deformation occurs at a critical loop density. Above it, plastic flow proceeds heterogeneously, creating defect-free channels in its wake. We find that channel initiation and size are mediated by loop coalescence resulting from elastic interactions with moving dislocations.

  19. Ground-state ordering of the J1-J2 model on the simple cubic and body-centered cubic lattices

    Science.gov (United States)

    Farnell, D. J. J.; Götze, O.; Richter, J.

    2016-06-01

    The J1-J2 Heisenberg model is a "canonical" model in the field of quantum magnetism in order to study the interplay between frustration and quantum fluctuations as well as quantum phase transitions driven by frustration. Here we apply the coupled cluster method (CCM) to study the spin-half J1-J2 model with antiferromagnetic nearest-neighbor bonds J1>0 and next-nearest-neighbor bonds J2>0 for the simple cubic (sc) and body-centered cubic (bcc) lattices. In particular, we wish to study the ground-state ordering of these systems as a function of the frustration parameter p =z2J2/z1J1 , where z1 (z2) is the number of nearest (next-nearest) neighbors. We wish to determine the positions of the phase transitions using the CCM and we aim to resolve the nature of the phase transition points. We consider the ground-state energy, order parameters, spin-spin correlation functions, as well as the spin stiffness in order to determine the ground-state phase diagrams of these models. We find a direct first-order phase transition at a value of p =0.528 from a state of nearest-neighbor Néel order to next-nearest-neighbor Néel order for the bcc lattice. For the sc lattice the situation is more subtle. CCM results for the energy, the order parameter, the spin-spin correlation functions, and the spin stiffness indicate that there is no direct first-order transition between ground-state phases with magnetic long-range order, rather it is more likely that two phases with antiferromagnetic long range are separated by a narrow region of a spin-liquid-like quantum phase around p =0.55 . Thus the strong frustration present in the J1-J2 Heisenberg model on the sc lattice may open a window for an unconventional quantum ground state in this three-dimensional spin model.

  20. Body centered cubic magnesium niobium hydride with facile room temperature absorption and four weight percent reversible capacity.

    Science.gov (United States)

    Tan, XueHai; Wang, Liya; Holt, Chris M B; Zahiri, Beniamin; Eikerling, Michael H; Mitlin, David

    2012-08-21

    We have synthesized a new metastable metal hydride with promising hydrogen storage properties. Body centered cubic (bcc) magnesium niobium hydride (Mg(0.75)Nb(0.25))H(2) possesses 4.5 wt% hydrogen gravimetric density, with 4 wt% being reversible. Volumetric hydrogen absorption measurements yield an enthalpy of hydride formation of -53 kJ mol(-1) H(2), which indicates a significant thermodynamic destabilization relative to the baseline -77 kJ mol(-1) H(2) for rutile MgH(2). The hydrogenation cycling kinetics are remarkable. At room temperature and 1 bar hydrogen it takes 30 minutes to absorb a 1.5 μm thick film at sorption cycle 1, and 1 minute at cycle 5. Reversible desorption is achieved in about 60 minutes at 175 °C. Using ab initio calculations we have examined the thermodynamic stability of metallic alloys with hexagonal close packed (hcp) versus bcc crystal structure. Moreover we have analyzed the formation energies of the alloy hydrides that are bcc, rutile or fluorite. PMID:22782120

  1. Crystal structure and hydrogen storage properties of body centered cubic 52Ti–12V–36Cr alloy doped with Zr7Ni10

    International Nuclear Information System (INIS)

    Highlights: • Two synthesis methods were performed to dope 52Ti–12V–36Cr alloy with Zr7Ni10. • Upon hydrogenation, the as-cast body centered cubic phase transforms into face centered cubic phase. • Easiness of the first activation and close results for thermodynamic parameters for both doping methods. - Abstract: The crystal structure and hydrogen sorption properties of 52Ti–12V–36Cr doped with Zr7Ni10 have been investigated. Two doping methods were used: (i) melting all the components together (single melt) and (ii) melting the alloy and Zr7Ni10 separately and thereafter re-melting them together (co-melt). The XRD patterns of both single melt and co-melt samples showed that these alloys crystallize in a body centered cubic (BCC) crystal structure. Upon hydrogenation, both doped 52Ti–12V–36Cr BCC alloys turns into Face Centered Cubic (FCC) phase. The single melt alloy exhibits a zirconium and nickel rich phase at the grain boundaries. This phase is well-distributed into the matrix and makes a connected network. The same network microstructure was observed in the co-melt. The single melt alloy exhibits an incubation time before its first hydrogenation (activation) whereas the co-melt alloy immediately started to absorb hydrogen. For both samples, the subsequent hydrogenation kinetic is fast. The maximum hydrogen capacities of the single melt and co-melt alloy are respectively 3.4 and 3.2 wt.%, but the high stability of these hydrides prevents them to desorb at room temperature. Single melt and co-melt alloys have similar thermodynamic parameters

  2. Phase transitions in the antiferromagnetic Ising model on a body-centered cubic lattice with interactions between next-to-nearest neighbors

    International Nuclear Information System (INIS)

    Phase transitions in the antiferromagnetic Ising model on a body-centered cubic lattice are studied on the basis of the replica algorithm by the Monte Carlo method and histogram analysis taking into account the interaction of next-to-nearest neighbors. The phase diagram of the dependence of the critical temperature on the intensity of interaction of the next-to-nearest neighbors is constructed. It is found that a second-order phase transition is realized in this model in the investigated interval of the intensities of interaction of next-to-nearest neighbors

  3. Theoretical Investigation of Stabilizing Mechanism by Boron in Body-Centered Cubic Iron Through (Fe,Cr)23(C,B)6 Precipitates

    Science.gov (United States)

    Sahara, Ryoji; Matsunaga, Tetsuya; Hongo, Hiromichi; Tabuchi, Masaaki

    2016-05-01

    Small amounts of boron improve the mechanical properties in high-chromium ferritic heat-resistant steels. In this work, the stabilizing mechanism by boron in body-centered cubic iron (bcc Fe) through (Fe,Cr)23(C,B)6 precipitates was investigated by first-principles calculations. Formation energy analysis of (Fe,Cr)23(C,B)6 reveals that the compounds become more stable to elemental solids as the boron concentration increases. Furthermore, the interface energy of bcc Fe(110) || Fe23(C,B)6(111) also decreases with boron concentration in the compounds. The decreased interface energy caused by boron addition is explained by the balance between the change in the phase stability of the precipitates and the change in the misfit parameter for the bcc Fe matrix and the precipitates. These results show that boron stabilizes the microstructure of heat-resistant steels, which is important for understanding the origins of the creep strength in ferritic steels.

  4. Thermodynamic properties of frustrated arbitrary spin-S J1-J2 quantum Heisenberg antiferromagnet on the body-centered-cubic lattice in random phase approximation

    Science.gov (United States)

    Mi, Bin-Zhou

    2016-07-01

    The thermodynamic properties of the frustrated arbitrary spin-S J1-J2 Heisenberg antiferromagnet on the body-centered-cubic lattice for Néel phase are systematically calculated by use of the double-time Green's function method within the random phase approximation (RPA). The role of spin quantum number and frustration strength on sublattice magnetization, Néel temperature, internal energy, and free energy are carefully analyzed. The curve of zero-temperature sublattice magnetization / S versus frustration strength J2/J1 values are almost flat at the larger spin quantum number S=10. With the increase of normalized temperature T/TN, the larger the spin quantum number S, the faster the / S drops, and the smaller influence of J2/J1 on the / S versus T/TN curve. Under the RPA approach, the Néel temperature TN /Sp and the internal energy E/Sp at the Néel point are independent of spin quantum number S. The numerical results show that the internal energy E/Sp at the Néel point seems independent of the frustration strength J2/J1. This indicates that thermodynamic quantities have universal characteristics for large spin quantum number.

  5. Aging characteristics and mechanical properties of 1600 MPa body-centered cubic Cu and B2-NiAl precipitation-strengthened ferritic steel

    International Nuclear Information System (INIS)

    High-strength low-carbon ferritic steels attaining a maximum yield strength of 1600 MPa by combined Cu and NiAl precipitation-strengthening were developed. The yield strength of the alloys increases monotonically with the total concentration of the principal alloying elements i.e. Mn, Cu, Ni and Al. At 12.40 at.%, a 1600 MPa yield strength is achieved after solution treatment at 950 °C followed by aging at 550 °C for 2 h. For all three alloys investigated, the hardness reached a maximum after 1–2 h aging at 500–550 °C. At peak hardness, the combined precipitation of the body-centered cubic (bcc) Cu-alloy and B2-ordered NiAl-type intermetallic precipitates is observed by atom probe tomography (APT). The morphology, composition and structure of the Cu-alloy and NiAl-type precipitates were characterized using APT and transmission electron microscopy, as a function of aging time at 550 °C. In peak hardness conditions, the equiaxed bcc Cu-alloyed precipitates contain substantial amounts of Fe and are enriched in Ni, Al and Mn. Ni and Mn segregate at the Cu-alloy precipitate/ferrite matrix interface. In addition to the segregation, B2 NiAl-type precipitates nucleate at the Cu-alloy precipitates. After aging for 2 h, most Cu-alloy precipitates have a NiAl-type precipitate attached to their side. On subsequent further aging, the Cu-alloyed precipitates enrich progressively with Cu and elongate, indicating a transformation to the 9R or face centered cubic structure. The Cu-alloyed precipitates coarsen slower than the NiAl-type precipitates due to interfacial energy differences between the two types of precipitates, slower diffusion kinetics of Cu through the NiAl precipitates, different matrix equilibrium solubility and solute transfer from Cu-alloyed precipitates to NiAl-type precipitates. The relatively slow growth and coarsening of Cu-alloyed precipitates are consistent with the observation of an only modest decrease of hardness with extended aging

  6. Post-growth thermal oxidation of wurtzite InN thin films into body-center cubic In2O3 for chemical/gas sensing applications

    International Nuclear Information System (INIS)

    Post-growth thermal oxidations of InN have been studied using high-resolution x-ray diffraction (HRXRD) and secondary ion-mass spectroscopy (SIMS). The InN thin films, having relative high crystal quality, were grown by metal–organic chemical vapor deposition (MOCVD) on c-sapphire substrates using InGaN/GaN buffer layers. HRXRD reveals that oxidation of wurtzite InN into body-center cubic In2O3 occurred at elevated temperatures. A Si3N4 encapsulation improves the crystal quality of In2O3 oxidized by using conventional rapid thermal annealing (RTA) but it results in the presence of undesired metallic indium. Cycle-RTA not only improves the crystal quality but also avoids the byproduct of metallic indium. SIMS depth profile, using contaminate elements as the ‘interface markers,’ provide evidence that the oxidation of InN is dominated by oxygen inward diffusion mechanism. Together with the HRXRD results, we conclude that the crystal quality of the resultant In2O3/InN heterostructure is mainly controlled by the balance between the speeds of oxygen diffusion and InN thermal dissociation, which can be effectively tuned by cycle-RTA. The obtained In2O3/InN heterostructures can be fundamental materials for studying high speed chemical/gas sensing devices. - Graphical abstract: Oxidation of h-InN into bcc-In2O3 has been realized at elevated temperatures. A Si3N4 cap improves the crystal quality of In2O3 oxidized by conventional RTA but it results in the presence of undesired metallic indium. Cycle-RTA not only improves the crystal quality but also avoids the byproduct of metallic indium. SIMS depth profiles provide evidence that the oxidation of InN is dominated by oxygen inward diffusion mechanism. The crystal quality of the resultant In2O3/InN heterostructure is mainly controlled by the balance between the speeds of oxygen diffusion and InN thermal dissociation, which can be effectively tuned by cycle-RTA. - Highlights: • Oxidation of h-InN into bcc-In2O3 has been

  7. Body-centered cubic ion correlation experiment

    International Nuclear Information System (INIS)

    The results of an interlaboratory correlation experiment involving eight laboratory sites studying the ion irradiation of molybdenum are presented. The program was comprised of three parts. The first part compared the radiation damage produced in a reference specimen of molybdenum by ions of different masses and different energies. The second part of the program compared measurements on a common micrograph supplied to all participants in the program. The results from all the sites agreed very well. The value of standard deviation in the measurement of void volume fraction corresponded to 10 percent of the average measured value and the spread between highest and lowest reported value was 35 percent. The third part of the program compared the microstructural characteristics of a transmission electron microscope (TEM) specimen that was passed from site to site (''round robin''). The results of this part of the experiment showed greater variations from the different participants than the results from the common micrograph. One of the principal sources of discrepancy was the measurement of the foil thickness which was necessary for computation of void number density. The standard deviation in the measurements of void volume fraction (swelling) corresponded to 20 percent of the measured average value. The spread between the highest and lowest value was 70 percent. This latter value gives an idea of the conceivable differences in results due to experimental techniques between two experiments

  8. Body-centered phase of shock loaded Cu

    OpenAIRE

    Neogi, Anupam; Mitra, Nilanjan

    2016-01-01

    Single crystal Cu when shock loaded in certain direction for a certain narrow range of piston velocities undergoes a structural phase transition from face-centered cubic to different body-centered phases. Based on molecular dynamic simulations, the manuscript identifies new phases of Cu through detailed radial distribution function and x-ray diffraction analysis. Identification of the new phases of Cu should initiate a re-evaluation of phase diagram for Cu under high temperature and pressure ...

  9. Vibrational Properties of Body-Centered Tetragonal C4

    International Nuclear Information System (INIS)

    Body-centered tetragonal C4 (bct C4) is a new form of crystalline sp3 carbon, which is found to be transparent, dynamically stable at zero pressure and more stable than graphite beyond 18.6 GPa. Symmetry analysis of the vibrational modes of bct C4 at Brillouin zone center is performed, Raman and infrared active modes are identified. The analysis results show that, different from cubic diamond and hexagonal diamond, there is an infrared active mode in bct C4. Based on first-principle method within the local density approximation, vibrational frequencies, Born effective charge tensors, and infrared absorption intensity of bct C4 are obtained. The vibrational modes of bct C4 are presented and compared with those of cubic diamond and hexagonal diamond in detail. (condensed matter: structural, mechanical, and thermal properties)

  10. Ising model on a face-centered cubic lattice at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Mazel' , A.E.

    1988-07-01

    The phase diagram of the model is constructed in a region of infinite degeneracy of the ground state that does not contain superdegenerate points. We consider the antiferromagnetic Ising model on a face-centered cubic lattice. This model is the simplest among an entire family of models used to describe binary alloys of the type CuAu. The more complicated models contain an interaction of not only the nearest neighbors and not only two-body interactions; however, the simplest variant still possesses the characteristic properties of the complete class of models. The main aim of the present paper is to give a rigorous proof of the fact that at sufficiently low temperatures there exist limiting Gibbs distributions corresponding to these most stable ground states. In the special case h /equal/ 0, this result was also obtained by Bricmont and Slavny.

  11. Synthesis and Characterization of Ru Cubic Nanocages with a Face-Centered Cubic Structure by Templating with Pd Nanocubes.

    Science.gov (United States)

    Zhao, Ming; Figueroa-Cosme, Legna; Elnabawy, Ahmed O; Vara, Madeline; Yang, Xuan; Roling, Luke T; Chi, Miaofang; Mavrikakis, Manos; Xia, Younan

    2016-08-10

    Nanocages have received considerable attention in recent years for catalytic applications owing to their high utilization efficiency of atoms and well-defined facets. Here we report, for the first time, the synthesis of Ru cubic nanocages with ultrathin walls, in which the atoms are crystallized in a face-centered cubic (fcc) rather than hexagonal close-packed (hcp) structure. The key to the success of this synthesis is to ensure layer-by-layer deposition of Ru atoms on the surface of Pd cubic seeds by controlling the reaction temperature and the injection rate of a Ru(III) precursor. By selectively etching away the Pd from the Pd@Ru core-shell nanocubes, we obtain Ru nanocages with an average wall thickness of 1.1 nm or about six atomic layers. Most importantly, the Ru nanocages adopt an fcc crystal structure rather than the hcp structure observed in bulk Ru. The synthesis has been successfully applied to Pd cubic seeds with different edge lengths in the range of 6-18 nm, with smaller seeds being more favorable for the formation of Ru shells with a flat, smooth surface due to shorter distance for the surface diffusion of the Ru adatoms. Self-consistent density functional theory calculations indicate that these unique fcc-structured Ru nanocages might possess promising catalytic properties for ammonia synthesis compared to hcp Ru(0001), on the basis of strengthened binding of atomic N and substantially reduced activation energies for N2 dissociation, which is the rate-determining step for ammonia synthesis on hcp Ru catalysts. PMID:27458871

  12. The evolution of recrystallization textures in body centered cubic metals

    International Nuclear Information System (INIS)

    A model of the evolution of recrystallization textures for b.c.c. metals was suggested based on the ODF and EBSD analysis of the texture change during annealing of cold rolled steel. The model is composed of two principles: first, the maximum principal stress direction in the deformed grain becomes the minimum Young's modulus direction in the recrystallized grain; second, a {110} plane, parallel to the maximum principal stress direction (hence, minimum Young's modulus direction), is taken for variant selection. The current model is successfully applied to describe the evolution of recrystallization textures in various b.c.c. transition metals such as tantalum, molybdenum and tungsten

  13. Lattice-gas model for alkali-metal fullerides: face-centered-cubic structure

    OpenAIRE

    Udvardi, Laszlo; Szabo, Gyorgy

    1995-01-01

    A lattice-gas model is suggested for describing the ordering phenomena in alkali-metal fullerides of face-centered-cubic structure assuming the electric charge of alkali ions residing in either octahedral or tetrahedral interstitial sites is completely screened by the first-neighbor C_60 molecules. This approximation allows us to derive an effective ion-ion interaction. The van der Waals interaction between the ion and C_60 molecule is characterized by introducing an additional energy at the ...

  14. Face-centered-cubic large-pore periodic mesoporous organosilicas with unsaturated and aromatic bridging groups.

    Science.gov (United States)

    Mandal, Manik; Manchanda, Amanpreet S; Zhuang, Jianqin; Kruk, Michal

    2012-06-12

    Large-pore ethenylene-bridged (-CH═CH-) and phenylene-bridged (-C(6)H(4)-) periodic mesoporous organosilicas (PMOs) with face-centered-cubic structure (Fm3m symmetry) of spherical mesopores were synthesized at 7 °C at low acid concentration (0.1 M HCl) using Pluronic F127 triblock copolymer surfactant in the presence of aromatic swelling agents (1,3,5-trimethylbenzene, xylenes-isomer mixture, and toluene). In particular, this work reports an unprecedented block-copolymer-templated well-ordered ethenylene-bridged PMO with cubic structure of spherical mesopores and an unprecedented block-copolymer-templated face-centered cubic phenylene-bridged PMO, which also has an exceptionally large unit-cell size and pore diameter. The unit-cell parameters of 30 and 25 nm and the mesopore diameters of 14 and 11 nm (nominal BJH-KJS pore diameters of 12-13 and 9 nm) were obtained for ethenylene-bridged and phenylene-bridged PMOs, respectively. Under the considered reaction conditions, the unit-cell parameters and pore diameters were found to be similar when the three different methyl-substituted benzene swelling agents were employed, although the degree of structural ordering appeared to improve for phenylene-bridged PMOs in the sequence of decreased number of methyl groups on the benzene ring. PMID:22607203

  15. Phonon densities of states of face-centered-cubic Ni-Fe alloys

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Matthew [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Mauger, L [California Institute of Technology, W. M. Keck Laboratory, Pasadena; Munoz, Jorge A. [California Institute of Technology, Pasadena; Halevy, I [California Institute of Technology, Pasadena; Horwath, J [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Semiatin, S L [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Leontsev, S. O. [University of Kentucky, Lexington; Stone, Matthew B [ORNL; Abernathy, Douglas L [ORNL; Xiao, Yuming [Carnegie Institution of Washington; Chow, P [HPCAT Geophysical Lab, Argonne, IL; Fultz, B. [California Institute of Technology, Pasadena

    2013-01-01

    Inelastic neutron scattering and nuclear resonant inelastic x-ray scattering were used to determine the phonon densities of states of face-centered-cubic Ni-Fe alloys. Increasing Fe concentration results in an average softening of the phonon modes. Chemical ordering of the Ni0.72Fe0.28 alloy results in a reduction of the partial vibrational entropy of the Fe atoms but does not significantly change the partial vibrational entropy of the Ni atoms. Changes in the phonon densities of states with composition and chemical ordering are discussed and analyzed with a cluster expansion method.

  16. Interstitialcy model for condensed matter states of face-centered-cubic metals

    Energy Technology Data Exchange (ETDEWEB)

    Granato, A.V. (Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign Urbana, Illinois 61801 (United States))

    1992-02-17

    The special configuration and dynamics known for interstitialcies in face-centered-cubic metals are exploited to construct a model giving all the thermodynamic properties of crystalline, liquid, and amorphous states in a unified way. A large diaelastic softening of the shear modulus with defect concentration is derived. This leads to a softening of the interstitialcy formation energy, which, taken together with a large entropy contribution from the interstitialcy resonance modes, makes the model, which contains Lindemann's law, viable for quantitative calculations of thermodynamic properties.

  17. Lattice Green functions of the higher-dimensional face-centered cubic lattices

    International Nuclear Information System (INIS)

    We study the face-centered cubic (fcc) lattice in up to six dimensions. In particular, we are concerned with lattice Green functions (LGFs) and return probabilities. Computer algebra techniques, such as the method of creative telescoping, are used for deriving an ODE for a given LGF. For the four- and five-dimensional fcc lattices, we give rigorous proofs of the ODEs that were conjectured by Guttmann and Broadhurst. Additionally, we find the ODE of the LGF of the six-dimensional fcc lattice, a result that was not believed to be achievable with current computer hardware. (paper)

  18. Molecular dynamics simulation of kink in 《100》 edge dislocation in body centred cubic iron

    Institute of Scientific and Technical Information of China (English)

    CHEN LiQun; WANG ChongYu; YU Tao

    2007-01-01

    Using the molecular dynamics method, we have constructed two kink models corresponding to the {010} and {011} edge dislocations (EDs) in body centred cubic (bcc) Fe.It is found that the geometric structure of a kink depends on the type of edge dislocation and the structural energies of the atoms sites in the dislocation core region.The formation energies, migration energies and widths of the kinks in different types of EDs are calculated.The results show that formation and migration of the kink in the {010} edge dislocation are difficult.The {011} edge dislocation moves primarily through kink nucleation, rather than kink migration.

  19. Atomic Mobilities in the Ag-Cu-Sn Face-Centered Cubic Lattice

    Science.gov (United States)

    Gierlotka, W.; Chen, Y. H.; Haque, M. A.; Rahman, M. A.

    2012-12-01

    Knowledge of atomic mobilities is necessary to predict the evolution of microstructure. The theoretical description of atomic mobilities is connected to the chemical potentials of the components in a given phase. A new thermodynamic description of the quaternary Ag-Cu-In-Sn system was recently published, and it is clear that a new description of the mobilities is also necessary. Based on the available literature and using Dictra software, optimization of the mobility parameters of silver, copper, and tin in the face-centered cubic phase was carried out. The results were compared with relevant data from literature as well as with our own experimental results. Good agreement between calculations and experiment was obtained.

  20. Rolling-induced Face Centered Cubic Titanium in Hexagonal Close Packed Titanium at Room Temperature

    Science.gov (United States)

    Wu, H. C.; Kumar, A.; Wang, J.; Bi, X. F.; Tomé, C. N.; Zhang, Z.; Mao, S. X.

    2016-04-01

    Combining transmission electron microscopes and density functional theory calculations, we report the nucleation and growth mechanisms of room temperature rolling induced face-centered cubic titanium (fcc-Ti) in polycrystalline hexagonal close packed titanium (hcp-Ti). Fcc-Ti and hcp-Ti take the orientation relation: hcp||fcc and , different from the conventional one. The nucleation of fcc-Ti is accomplished via pure-shuffle mechanism with a minimum stable thickness of three atomic layers, and the growth via shear-shuffle mechanisms through gliding two-layer disconnections or pure-shuffle mechanisms through gliding four-layer disconnections. Such phase transformation offers an additional plastic deformation mode comparable to twinning.

  1. Consistent Analytic Embedded Atom Potential for Face-Centered Cubic Metals and Alloys

    Institute of Scientific and Technical Information of China (English)

    Iyad A. Hijazi; Young Ho Park

    2009-01-01

    A consistent empirical embedded-atom potential that includes a long range force was developed for fcc (face-centered cubic) metals and alloys. The proposed potential for pure metals does not require modification of the initial function form when being applied to alloy systems. The potential parameters of this model were determined by fitting lattice constant, three elastic constants, cohesive energy, and vacancy formation energies of the pure metals and the heats of solution of the binary alloys via an optimization technique. Parameters for Ag, Al, Au, Cu, Ni, Pd and Pt were obtained. The obtained parameters were used to calculate the bulk modulus, divacancy formation energy, crystal stability, stacking fault energy, vacancy migration energy, and melting point for each pure metal and the heats of formation and lattice constants for binary alloys. The predicted values were in good agreement with experimental results.

  2. High dose effects in neutron irradiated face-centered cubic metals

    International Nuclear Information System (INIS)

    During neutron irradiation, most face-centered cubic metals and alloys develop saturation or quasi-steady state microstructures. This, in turn, leads to saturation levels in mechanical properties and quasi-steady state rates of swelling and creep deformation. Swelling initially plays only a small role in determining these saturation states, but as swelling rises to higher levels, it exerts strong feedback on the microstructure and its response to environmental variables. The influence of swelling, either directly or indirectly via second order mechanisms, such as elemental segregation to void surfaces, eventually causes major changes, not only in irradiation creep and mechanical properties, but also on swelling itself. The feedback effects of swelling on irradiation creep are particularly complex and lead to problems in applying creep data derived from highly pressurized creep tubes to low stress situations, such as fuel pins in liquid metal reactors

  3. High dose effects in neutron irradiated face-centered cubic metals

    Energy Technology Data Exchange (ETDEWEB)

    Garner, F.A. [Pacific Northwest Lab., Richland, WA (United States); Toloczko, M.B. [California Univ., Santa Barbara, CA (United States)

    1993-06-01

    During neutron irradiation, most face-centered cubic metals and alloys develop saturation or quasi-steady state microstructures. This, in turn, leads to saturation levels in mechanical properties and quasi-steady state rates of swelling and creep deformation. Swelling initially plays only a small role in determining these saturation states, but as swelling rises to higher levels, it exerts strong feedback on the microstructure and its response to environmental variables. The influence of swelling, either directly or indirectly via second order mechanisms, such as elemental segregation to void surfaces, eventually causes major changes, not only in irradiation creep and mechanical properties, but also on swelling itself. The feedback effects of swelling on irradiation creep are particularly complex and lead to problems in applying creep data derived from highly pressurized creep tubes to low stress situations, such as fuel pins in liquid metal reactors.

  4. Formation of recrystallization cube texture in high purity face-centered cubic metal sheets

    Energy Technology Data Exchange (ETDEWEB)

    Mao, W.

    1999-10-01

    An investigation on recrystallization textures in high purity face-centered cubic (fcc) aluminum, copper, and nickel indicated that the cube texture is a unique dominant final texture. In a macroview of rolling deformation, a balanced activation of four slip systems can result in certain stability of some substructure with cube orientation in the deformed matrix. In the stable substructure the dislocation density is very low, and the dislocation configuration is rather simple in comparison to other orientations so that the cube substructure can easily be transformed into cube recrystallization nuclei by a recovery process. A high orientation gradient and correspondingly high angle boundaries to the deformed matrix are usually expected around the cube nuclei, which, therefore, grow rapidly. After the primary recrystallization, the size of cube grains is much larger than the grains with other orientations, which will be expensed as the cube grains grow further, so that the cube texture can finally become a dominant texture component.

  5. Magnetism of iron in face-centered cubic 4d metals

    Energy Technology Data Exchange (ETDEWEB)

    Elzain, M.; Al Rawas, A.; Yousif, A.; Gismelseed, A.; Rais, A.; Al Omari, I.; Widatallah, H. [Physics Department, College of Science, Box 36, Sultan Qaboos University, Al Khod 123 (Oman)

    2004-05-01

    The magnetic moments and hyperfine fields at iron sites embedded in Rh, Pd and Ag face centered cubic structures were calculated using the first principle discrete variational method (DVM) and the full-potential linear-augment plane wave (FP-LAPW) method. In DVM the systems were represented by, clusters of atoms, while in FP-LAPW supercells were used. The objectives of this work are to compare and contrast results from the two different computational methods in addition to comparison to experimental data. Large magnetic moments were obtained for iron in Pd, relatively smaller moments for iron in Ag and smaller moments for iron in Rh. Iron atoms were found to couple ferromagnetically to Pd atoms and antiferromagnetically to Rh. No moment is induced on the Ag atom. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Equilibrium concentration of lattice vacancies in magnetic alloys with face centered cubic lattice having in interstitial atoms

    International Nuclear Information System (INIS)

    In this paper we studied simultaneously influence of interstitial atoms, magnetic ordering and atoms ordering on the equilibrium concentration of lattice vacancies in face centered cubic lattice. Calculating we take in account the interaction between nearest neighbouring atoms and we neglected correlations between atoms. (author). 5 refs., 1 tab

  7. Stacking fault energy of face-centered cubic metals: thermodynamic and ab initio approaches.

    Science.gov (United States)

    Li, Ruihuan; Lu, Song; Kim, Dongyoo; Schönecker, Stephan; Zhao, Jijun; Kwon, Se Kyun; Vitos, Levente

    2016-10-01

    The formation energy of the interface between face-centered cubic (fcc) and hexagonal close packed (hcp) structures is a key parameter in determining the stacking fault energy (SFE) of fcc metals and alloys using thermodynamic calculations. It is often assumed that the contribution of the planar fault energy to the SFE has the same order of magnitude as the bulk part, and thus the lack of precise information about it can become the limiting factor in thermodynamic predictions. Here, we differentiate between the interfacial energy for the coherent fcc(1 1 1)/hcp(0 0 0 1) interface and the 'pseudo-interfacial energy' that enters the thermodynamic expression for the SFE. Using first-principles calculations, we determine the coherent and pseudo-interfacial energies for six elemental metals (Al, Ni, Cu, Ag, Pt, and Au) and three paramagnetic Fe-Cr-Ni alloys. Our results show that the two interfacial energies significantly differ from each other. We observe a strong chemistry dependence for both interfacial energies. The calculated pseudo-interfacial energies for the Fe-Cr-Ni steels agree well with the available literature data. We discuss the effects of strain on the description of planar faults via thermodynamic and ab initio approaches. PMID:27484794

  8. Quantitative modeling of solute drag by vacancies in face-centered-cubic alloys

    Science.gov (United States)

    Garnier, Thomas; Trinkle, Dallas R.; Nastar, Maylise; Bellon, Pascal

    2014-04-01

    Transport coefficients, the elements of the so-called Onsager matrix, are essential quantities for modeling solid-state kinetics controlled by diffusion. In a face-centered-cubic structure, drag of solute atoms by vacancies can be caused by solute-vacancy binding at nearest neighbors. In order to investigate solute drag in alloys with interactions up to the third-nearest-neighbor sites, we extend an analytic method: the self-consistent mean field method. With this method, we calculate the Onsager matrix of model alloys to identify kinetic effects arising from individual and collective jump frequencies and assess the results on select cases using atomic kinetic Monte Carlo simulations. Using preexisting density functional theory data from various sources, we show that many impurities have low-temperature solute drag before changing to solute exchange at high temperatures. We evaluate the transition temperature for these alloys between these two regimes and compare the results with available experimental data. Some disagreement is found, which can be due both to experimental and numerical shortcomings. In order to guide diffusion calculations, the sensitivity of the Onsager matrix to the range of the kinetic correlation and to the input density functional theory data is studied.

  9. A three-dimensional photonic crystal model: Hollow-spherical non-closed-packed face-centered cubic structure

    Energy Technology Data Exchange (ETDEWEB)

    Chen Hongbo [National Laboratory of Superhard Materials, 10 Qianwei Road, Jilin University, Changchun 130012 (China); Cao Yanling [National Laboratory of Superhard Materials, 10 Qianwei Road, Jilin University, Changchun 130012 (China); Zhu Yongzheng [National Laboratory of Superhard Materials, 10 Qianwei Road, Jilin University, Changchun 130012 (China); Wang Yanping [National Laboratory of Superhard Materials, 10 Qianwei Road, Jilin University, Changchun 130012 (China); Chi Yuanbin [National Laboratory of Superhard Materials, 10 Qianwei Road, Jilin University, Changchun 130012 (China)]. E-mail: chiyb@jlu.edu.cn

    2006-05-31

    We report a photonic crystal model, which consists of hollow spheres located at face-centered cubic lattice sites and each sphere connected to all of its 12 nearest neighbors by cylindrical rods. Theoretical calculations show that this kind of structure exhibits two large complete photonic band gaps. The maximum relative gap sizes reach 17.3% between the eighth and ninth bands, and 15.1% between the 13th and 14th bands for a dielectric contrast of 11.9, and the minimal dielectric contrasts needed to open the two gaps are 5.8 and 7.3, respectively, which are lower than that of other face-centered cubic photonic crystal structures.

  10. Kinetics of Hexagonal Cylinders to Face-centered Cubic Spheres Transition of Triblock Copolymer in Selective Solvent: Brownian Dynamics Simulation

    OpenAIRE

    LI Minghai; Liu, Yongsheng; Bansil, Rama

    2010-01-01

    The kinetics of the transformation from the hexagonal packed cylinder (HEX) phase to the face-centered-cubic (FCC) phase was simulated using Brownian Dynamics for an ABA triblock copolymer in a selective solvent for the A block. The kinetics was obtained by instantaneously changing either the temperature of the system or the well-depth of the Lennard-Jones potential. Detailed analysis showed that the transformation occurred via a rippling mechanism. The simulation results indicated that the o...

  11. Wang-Landau sampling in face-centered-cubic hydrophobic-hydrophilic lattice model proteins

    Science.gov (United States)

    Liu, Jingfa; Song, Beibei; Yao, Yonglei; Xue, Yu; Liu, Wenjie; Liu, Zhaoxia

    2014-10-01

    Finding the global minimum-energy structure is one of the main problems of protein structure prediction. The face-centered-cubic (fcc) hydrophobic-hydrophilic (HP) lattice model can reach high approximation ratios of real protein structures, so the fcc lattice model is a good choice to predict the protein structures. The lacking of an effective global optimization method is the key obstacle in solving this problem. The Wang-Landau sampling method is especially useful for complex systems with a rough energy landscape and has been successfully applied to solving many optimization problems. We apply the improved Wang-Landau (IWL) sampling method, which incorporates the generation of an initial conformation based on the greedy strategy and the neighborhood strategy based on pull moves into the Wang-Landau sampling method to predict the protein structures on the fcc HP lattice model. Unlike conventional Monte Carlo simulations that generate a probability distribution at a given temperature, the Wang-Landau sampling method can estimate the density of states accurately via a random walk, which produces a flat histogram in energy space. We test 12 general benchmark instances on both two-dimensional and three-dimensional (3D) fcc HP lattice models. The lowest energies by the IWL sampling method are as good as or better than those of other methods in the literature for all instances. We then test five sets of larger-scale instances, denoted by the S, R, F90, F180, and CASP target instances on the 3D fcc HP lattice model. The numerical results show that our algorithm performs better than the other five methods in the literature on both the lowest energies and the average lowest energies in all runs. The IWL sampling method turns out to be a powerful tool to study the structure prediction of the fcc HP lattice model proteins.

  12. Current-direction dependence of the transport properties in single-crystalline face-centered-cubic cobalt films

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, X.; Liang, J. H.; Chen, B. L.; Li, J. X.; Ding, Z.; Wu, Y. Z., E-mail: wuyizheng@fudan.edu.cn [Department of Physics, State Key Laboratory of Surface Physics and Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433 (China); Ma, D. H. [Department of Energy Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2015-07-28

    Face-centered-cubic cobalt films are epitaxially grown on insulating LaAlO{sub 3}(001) substrates by molecular beam epitaxy. Transport measurements are conducted in different current directions relative to the crystal axes. We find that the temperature dependent anisotropic magnetoresistance ratio strongly depends on the current direction. However, the anomalous Hall effect shows isotropic behavior independent of the current direction. Our results demonstrate the interplay between the current direction and the crystalline lattice in single-crystalline ferromagnetic films. A phenomenological analysis is presented to interpret the experimental data.

  13. Elastic limit for surface step dislocation nucleation in face-centered cubic metals: Temperature and step height dependence

    International Nuclear Information System (INIS)

    The influences of surface step state and temperature on the elastic limit for dislocation nucleation from a surface step were analyzed by means of atomic scale simulations in face-centered cubic metals. When varying the step height, two regimes were found: for smaller steps, local effects dominate, whereas for larger steps, the stress concentration prevails. The differences observed for the elastic limit were correlated to relevant properties of the different potentials. Finally, for aluminum, the implication of the activation parameters in the nucleation strain was studied in greater detail. This study is particularly relevant to nanostructures, where plasticity is most often governed by dislocation nucleation rather than dislocation multiplication.

  14. Analysis of a Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Wu, Hsi-Yung T.; Shaw, Peter; Przekop, Adam

    2013-01-01

    The hybrid wing body center section test article is an all-composite structure made of crown, floor, keel, bulkhead, and rib panels utilizing the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) design concept. The primary goal of this test article is to prove that PRSEUS components are capable of carrying combined loads that are representative of a hybrid wing body pressure cabin design regime. This paper summarizes the analytical approach, analysis results, and failure predictions of the test article. A global finite element model of composite panels, metallic fittings, mechanical fasteners, and the Combined Loads Test System (COLTS) test fixture was used to conduct linear structural strength and stability analyses to validate the specimen under the most critical combination of bending and pressure loading conditions found in the hybrid wing body pressure cabin. Local detail analyses were also performed at locations with high stress concentrations, at Tee-cap noodle interfaces with surrounding laminates, and at fastener locations with high bearing/bypass loads. Failure predictions for different composite and metallic failure modes were made, and nonlinear analyses were also performed to study the structural response of the test article under combined bending and pressure loading. This large-scale specimen test will be conducted at the COLTS facility at the NASA Langley Research Center.

  15. Kinetics of Hexagonal Cylinders to Face-centered Cubic Spheres Transition of Triblock Copolymer in Selective Solvent: Brownian Dynamics Simulation

    CERN Document Server

    Li, Minghai; Bansil, Rama

    2010-01-01

    The kinetics of the transformation from the hexagonal packed cylinder (HEX) phase to the face-centered-cubic (FCC) phase was simulated using Brownian Dynamics for an ABA triblock copolymer in a selective solvent for the A block. The kinetics was obtained by instantaneously changing either the temperature of the system or the well-depth of the Lennard-Jones potential. Detailed analysis showed that the transformation occurred via a rippling mechanism. The simulation results indicated that the order-order transformation (OOT) was a nucleation and growth process when the temperature of the system instantly jumped from 0.8 to 0.5. The time evolution of the structure factor obtained by Fourier Transformation showed that the peak intensities of the HEX and FCC phases could be fit well by an Avrami equation.

  16. First-principles LDA + U calculations investigating the lattice contraction of face-centered cubic Pu hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Ao, B.Y., E-mail: aobingyun24@yahoo.com.cn [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China); Wang, X.L.; Shi, P.; Chen, P.H.; Ye, X.Q.; Lai, X.C. [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China); Gao, T., E-mail: gaotao@scu.edu.cn [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China)

    2012-05-15

    Plutonium metal can be loaded with hydrogen, which forms complicated solid solutions and compounds, and leads to significant changes in electronic structure. A first-principles pseudopotential plane wave method with added Hubbard parameter U was employed to investigate the electronic and structural properties of face-centered cubic Pu hydrides (PuH{sub x}, x = 2, 2.25, and 3). The decrease in calculated lattice parameters with increasing x is in reasonable agreement with experimental findings. Comparative analysis of the electronic-structure results for a series of PuH{sub x} compositions reveals that lattice contraction occurs due to enhanced chemical bonding and the size effects involving interstitial atoms. We find that the size effects are the driving force for the abnormal lattice contraction.

  17. Stochastic behaviors in plastic deformation of face-centered cubic micropillars governed by surface nucleation and truncated source operation

    International Nuclear Information System (INIS)

    Three dimensional dislocation dynamics (DD) simulations are performed to investigate the governing mechanism of size dependent plastic deformation in submicron face-centered cubic (fcc) micropillars under uniaxial loading. Based on previous atomistic simulations, we introduce an algorithm for dislocation nucleation at the free surface as a function of stress and temperature in the DD simulation. The simulation results show stochastic behaviors in agreement with experimental observations, and reveal that dislocation nucleation at the free surface is the dominant mechanism of plastic flow in small pillars with diameters less than 200 nm, while the operation of truncated dislocation sources is the governing mechanism in large pillars with diameters exceeding 1 μm. In between, both mechanisms come into play in a stochastic way

  18. Molecular dynamics simulations on size dependent tensile deformation behaviour of [110] oriented body centred cubic iron nanowires

    International Nuclear Information System (INIS)

    Tensile deformation behaviour of 〈110〉/{111} oriented body centred cubic (BCC) iron nanowires has been examined using molecular dynamics (MD) simulations at 10 K. MD simulations were performed on nanowires with cross section width in the range 1.42–24.27 nm. The results indicated that the deformation behaviour in BCC Fe nanowires is governed by full dislocation slip irrespective of nanowire size. The initiation of plastic deformation occurred by the collective emission of dislocation loops originating from the corner of the nanowires. Following yielding, accumulation of straight screw dislocations with increasing plastic deformation has been observed. Presence of curved slip steps observed in the surface morphology suggested the occurrence of cross slip in large size nanowires. Evidence of cross slip was not noticed in small size nanowires. The variations of Young’s modulus, yield strength and flow stress with nanowire size displaying strong size effects in BCC Fe nanowires have been presented

  19. Electronic structure and metallization of cubic GdH3 under pressure: Ab initio many-body GW calculations

    Science.gov (United States)

    Kong, Bo; Zhang, Yachao

    2016-07-01

    The electronic structures of the cubic GdH3 are extensively investigated using the ab initio many-body GW calculations treating the Gd 4f electrons either in the core (4f-core) or in the valence states (4f-val). Different degrees of quasiparticle (QP) self-consistent calculations with the different starting points are used to correct the failures of the GGA/GGA + U/HSE03 calculations. In the 4f-core case, GGA + G0W0 calculations give a fundamental band gap of 1.72 eV, while GGA+ GW0 or GGA + GW calculations present a larger band gap. In the 4f-val case, the nonlocal exchange-correlation (xc) functional HSE03 can account much better for the strong localization of the 4f states than the semilocal or Hubbard U corrected xc functional in the Kohn-Sham equation. We show that the fundamental gap of the antiferromagnetic (AFM) or ferromagnetic (FM) GdH3 can be opened up by solving the QP equation with improved starting point of eigenvalues and wave functions given by HSE03. The HSE03 + G0W0 calculations present a fundamental band gap of 2.73 eV in the AFM configuration, and the results of the corresponding GW0 and GW calculations are 2.89 and 3.03 eV, respectively. In general, for the cubic structure, the fundamental gap from G0W0 calculations in the 4f-core case is the closest to the real result. By G0W0 calculations in the 4f-core case, we find that H or Gd defects can strongly affect the band structure, especially the H defects. We explain the mechanism in terms of the possible electron correlation on the hydrogen site. Under compression, the insulator-to-metal transition in the cubic GdH3 occurs around 40 GPa, which might be a satisfied prediction.

  20. Kinetics of hexagonal-body-centered cubic transition in a triblock

    Czech Academy of Sciences Publication Activity Database

    Li, M.; Liu, Y.; Nie, H.; Bansil, R.; Steinhart, Miloš

    2007-01-01

    Roč. 40, č. 26 (2007), s. 9491-9502. ISSN 0024-9297 R&D Projects: GA AV ČR IAA100500501 Institutional research plan: CEZ:AV0Z40500505 Keywords : SAXS * phase transitions * block copolymers in selective solvents Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.411, year: 2007

  1. Center of pressure velocity reflects body acceleration rather than body velocity during quiet standing.

    Science.gov (United States)

    Masani, Kei; Vette, Albert H; Abe, Masaki O; Nakazawa, Kimitaka

    2014-03-01

    The purpose of this study was to test the hypothesis that the center of pressure (COP) velocity reflects the center of mass (COM) acceleration due to a large derivative gain in the neural control system during quiet standing. Twenty-seven young (27.2±4.5 years) and twenty-three elderly (66.2±5.0 years) subjects participated in this study. Each subject was requested to stand quietly on a force plate for five trials, each 90 s long. The COP and COM displacements, the COP and COM velocities, and the COM acceleration were acquired via a force plate and a laser displacement sensor. The amount of fluctuation of each variable was quantified using the root mean square. Following the experimental study, a simulation study was executed to investigate the experimental findings. The experimental results revealed that the COP velocity was correlated with the COM velocity, but more highly correlated with the COM acceleration. The equation of motion of the inverted pendulum model, however, accounts only for the correlation between the COP and COM velocities. These experimental results can be meaningfully explained by the simulation study, which indicated that the neural motor command presumably contains a significant portion that is proportional to body velocity. In conclusion, the COP velocity fluctuation reflects the COM acceleration fluctuation rather than the COM velocity fluctuation, implying that the neural motor command controlling quiet standing posture contains a significant portion that is proportional to body velocity. PMID:24444652

  2. Magnetic cluster expansion model for random and ordered magnetic face-centered cubic Fe-Ni-Cr alloys

    Science.gov (United States)

    Lavrentiev, M. Yu.; Wróbel, J. S.; Nguyen-Manh, D.; Dudarev, S. L.; Ganchenkova, M. G.

    2016-07-01

    A Magnetic Cluster Expansion model for ternary face-centered cubic Fe-Ni-Cr alloys has been developed, using DFT data spanning binary and ternary alloy configurations. Using this Magnetic Cluster Expansion model Hamiltonian, we perform Monte Carlo simulations and explore magnetic structures of alloys over the entire range of compositions, considering both random and ordered alloy structures. In random alloys, the removal of magnetic collinearity constraint reduces the total magnetic moment but does not affect the predicted range of compositions where the alloys adopt low-temperature ferromagnetic configurations. During alloying of ordered fcc Fe-Ni compounds with Cr, chromium atoms tend to replace nickel rather than iron atoms. Replacement of Ni by Cr in ordered alloys with high iron content increases the Curie temperature of the alloys. This can be explained by strong antiferromagnetic Fe-Cr coupling, similar to that found in bcc Fe-Cr solutions, where the Curie temperature increase, predicted by simulations as a function of Cr concentration, is confirmed by experimental observations. In random alloys, both magnetization and the Curie temperature decrease abruptly with increasing chromium content, in agreement with experiment.

  3. Mechanism-based crystal plasticity modeling of twin boundary migration in nanotwinned face-centered-cubic metals

    Science.gov (United States)

    Mirkhani, Hamidreza; Joshi, Shailendra P.

    2014-08-01

    Nanotwinned (nt) metals are an important subset of nanostructured materials because they exhibit impressive strength and ductility. Several recent investigations on nt face-centered-cubic (FCC) metals indicate that their macroscopic responses emerge from complex microscopic mechanisms that are dominated by dislocation-TB interactions. Under applied stimulus, nt microstructures evolve through migration of twin boundaries (TBs) that may have implications on the material strength and stability. This work focuses on modeling TB migration within finite element framework in an explicit manner and studying its effects on the micromechanics of twinned FCC metals under quasi-static loading conditions. The theoretical setting is developed using three-dimensional single crystal plasticity as a basis wherein the plastic slip on the {111} slip systems in an FCC crystal structure is modeled as visco-plastic behavior. Owing to their governing role, twins are modeled as discrete lamellas with full crystallographic anisotropy. To model TB migration, an additional visco-plastic slip-law for twinning partial systems ({111}) based on the nucleation and motion of twin partial dislocations is introduced. This size-dependent constitutive law is presumed to prevail in the vicinity of the TB and naturally facilitates TB migration when combined with a twinning condition that is based on the accrual of the necessary shear strain. The constitutive development is implemented within a finite element framework through a User Material (UMAT) facility within ABAQUS/STANDARD®. Detailed micromechanics simulations on model microstructures involving single-grained and polycrystalline topologies are presented.

  4. Energy-landscape paving for prediction of face-centered-cubic hydrophobic-hydrophilic lattice model proteins

    Science.gov (United States)

    Liu, Jingfa; Song, Beibei; Liu, Zhaoxia; Huang, Weibo; Sun, Yuanyuan; Liu, Wenjie

    2013-11-01

    Protein structure prediction (PSP) is a classical NP-hard problem in computational biology. The energy-landscape paving (ELP) method is a class of heuristic global optimization algorithm, and has been successfully applied to solving many optimization problems with complex energy landscapes in the continuous space. By putting forward a new update mechanism of the histogram function in ELP and incorporating the generation of initial conformation based on the greedy strategy and the neighborhood search strategy based on pull moves into ELP, an improved energy-landscape paving (ELP+) method is put forward. Twelve general benchmark instances are first tested on both two-dimensional and three-dimensional (3D) face-centered-cubic (fcc) hydrophobic-hydrophilic (HP) lattice models. The lowest energies by ELP+ are as good as or better than those of other methods in the literature for all instances. Then, five sets of larger-scale instances, denoted by S, R, F90, F180, and CASP target instances on the 3D FCC HP lattice model are tested. The proposed algorithm finds lower energies than those by the five other methods in literature. Not unexpectedly, this is particularly pronounced for the longer sequences considered. Computational results show that ELP+ is an effective method for PSP on the fcc HP lattice model.

  5. First-principles path-integral molecular dynamics study of diffusion process of hydrogen in face-centered cubic metals

    Science.gov (United States)

    Kimizuka, Hajime; Ogata, Shigenobu

    We investigated the H diffusivity in face-centered cubic Pd and Al by performing path-integral molecular dynamics (PIMD) modeling in the framework of density functional theory (DFT); in our calculations, we took nuclear quantum effects into consideration. The DFT results showed that the H-migration barriers (Em) in Pd and Al exhibited similar values (approximately 0.16 eV), while the H atoms were stable at octahedral (O) sites for Pd and at tetrahedral (T) sites for Al. The PIMD-based free-energy profiles for H migration between the O-site and T-site were evaluated using the thermodynamic integration of the centroid forces at 150-600 K. We confirmed that the quantum effects significantly affected the Em and the difference between the energies of the H atom at the O-site and the T-site (EO - T); The Em and EO - T values in Pd at 300 K increased by 32% and 98%, respectively, relative to the classical limit. On the other hand, the Em and ET - O (i.e., -EO - T) values in Al at 300 K decreased by 3% and 41%, respectively. This suggested that the quantum nature of H nuclei was essential for understanding the H-diffusion kinetics in these metals even above ambient temperature.

  6. The Practical Application of Body-Mind Centering[R] (BMC) in Dance Pedagogy

    Science.gov (United States)

    Eddy, Martha

    2006-01-01

    Based in bodily awareness, somatic education has many points of relationship with dance education. Body-Mind Centering[R] (BMC), with some of its roots in Laban Movement Analysis/Bartenieff Fundamentals (LMA/BF), has a particularly easy link to dance. When studying Body-Mind Centering, the theoretical components are often taught through dance…

  7. Building "Bob": A Project Exploring the Human Body at Western Illinois University Preschool Center

    Science.gov (United States)

    Brouette, Scott

    2008-01-01

    When the children at Western Illinois University Preschool Center embarked on a study of human bodies, they decided to build a life-size model of a body, organ by organ from the inside out, to represent some of the things they were learning. This article describes the building of "Bob," the human body model, highlighting the children's problem…

  8. Bismuth doping strategies in GeTe nanowires to promote high-temperature phase transition from rhombohedral to face-centered cubic structure

    International Nuclear Information System (INIS)

    The phase transition of Bi-doped (∼3 at. %) GeTe nanowires from a rhombohedral (R) to a face-centered cubic (C) structure was observed in in situ high-temperature X-ray diffraction. The promotion of high-temperature R-C phase transition by a doping approach was revealed. Ab initio energy calculations of doped GeTe at various Bi doping concentrations were performed to interpret the promoted temperature-induced phase transitions. Those results indicated that the total energy differences between R and C structures of doped GeTe decreased as Bi doping concentrations increased, which facilitated R-C phase transitions

  9. Bismuth doping strategies in GeTe nanowires to promote high-temperature phase transition from rhombohedral to face-centered cubic structure

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie; Huang, Rong; Wei, Fenfen; Cheng, Guosheng, E-mail: gscheng2006@sinano.ac.cn [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, 398 Ruoshui Road, Suzhou Industrial Park, Jiangsu 215123 (China); University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049 (China); Kong, Tao [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, 398 Ruoshui Road, Suzhou Industrial Park, Jiangsu 215123 (China)

    2014-11-17

    The phase transition of Bi-doped (∼3 at. %) GeTe nanowires from a rhombohedral (R) to a face-centered cubic (C) structure was observed in in situ high-temperature X-ray diffraction. The promotion of high-temperature R-C phase transition by a doping approach was revealed. Ab initio energy calculations of doped GeTe at various Bi doping concentrations were performed to interpret the promoted temperature-induced phase transitions. Those results indicated that the total energy differences between R and C structures of doped GeTe decreased as Bi doping concentrations increased, which facilitated R-C phase transitions.

  10. Nonnegative, conserved scalar transport using grid-cell-centered, spectrally constrained blackman cubics for applications on a variable-thickness mesh

    International Nuclear Information System (INIS)

    A flux-formulated advection scheme is developed based on local, grid cell centered cubic polynomials. The coefficients of these polynomials involve a weighted admixture of locally and globally defined derivatives and are subjected to constraints developed from special theory. The continuous polynomials are subsequently replaced with a multipoint representation that eliminates the possibility of negative concentrations and conserves mass exactly. The performance of this new, low-numerical-diffusion transport scheme is compared with several other transport schemes. 18 refs., 5 figs., 3 tabs

  11. Small-body surveys and the Minor Planet Center perspective

    Science.gov (United States)

    Spahr, T.

    2014-07-01

    Surveys for small bodies in the Solar System have dramatically expanded capacity and capability over the last two decades; the principal reason being the shift from photographic to digital imaging and reduction techniques. This talk will discuss our current knowledge of minor planet and comet populations, as well as the main surveys responsible for the discovery of these objects. Amateur and professional contributions to the Solar System inventory will be discussed as well. Lastly there will be a discussion of future surveys, with an emphasis on the lessons learned from Pan-STARRS and NEOWISE.

  12. A Monte Carlo Simulation of a Monomer Dimer CO-O2 Catalytic Reaction on the Surface and Subsurface of a Face-centered Cubic Lattice

    Institute of Scientific and Technical Information of China (English)

    K.Iqbal; A.Basit

    2011-01-01

    @@ The presence of oxygen in the subsurface in monomer-dimer reactions(CO-O2 and NO-CO)is observed experimentally.The effect of subsurface oxygen on a CO-O2 catalytic reaction on a face-centered cubic(FCC)lattice is studied using Monte Carlo simulation.The effect of adding subsurface neighbours on the phase diagram is also extensively explored.It is observed that the subsurface oxygen totally eliminates the typical second order phase transition.It is also shown that the introduction of the diffusion of O atoms and the subsurface of the FCC lattice shifts the single transition point towards the stoichiometric ratio.%The presence of oxygen in the subsurface in monomer-dimer reactions (CO-O2 and NO-CO) is observed experimentally. The effect of subsurface oxygen on a CO-O2 catalytic reaction on a face-centered cubic (FCC) lattice is studied using Monte Carlo simulation. The effect of adding subsurface neighbours on the phase diagram is also extensively explored. It is observed that the subsurface oxygen totally eliminates the typical second order phase transition. It is also shown that the introduction of the diffusion of O atoms and the subsurface of the FCC lattice shifts the single transition point towards the stoichiometric ratio.

  13. Exploitation of 3D face-centered cubic mesoporous silica as a carrier for a poorly water soluble drug: Influence of pore size on release rate

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Wenquan; Wan, Long; Zhang, Chen; Gao, Yikun; Zheng, Xin; Jiang, Tongying; Wang, Siling, E-mail: silingwang@syphu.edu.cn

    2014-01-01

    The purposes of the present work were to explore the potential application of 3D face-centered cubic mesoporous silica (FMS) with pore size of 16.0 nm as a delivery system for poorly soluble drugs and investigate the effect of pore size on the dissolution rate. FMS with different pore sizes (16.0, 6.9 and 3.7 nm) was successfully synthesized by using Pluronic block co-polymer F127 as a template and adjusting the reaction temperatures. Celecoxib (CEL), which is a BCS class II drug, was used as a model drug and loaded into FMS with different pore sizes by the solvent deposition method at a drug–silica ratio of 1:4. Characterization using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nitrogen adsorption, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) was used to systematically investigate the drug loading process. The results obtained showed that CEL was in a non-crystalline state after incorporation of CEL into the pores of FMS-15 with pore size of 16.0 nm. In vitro dissolution was carried out to demonstrate the effects of FMS with different pore sizes on the release of CEL. The results obtained indicated that the dissolution rate of CEL from FMS-15 was significantly enhanced compared with pure CEL. This could be explained by supposing that CEL encountered less diffusion resistance and its crystallinity decreased due to the large pore size of 16.0 nm and the nanopore channels of FMS-15. Moreover, drug loading and pore size both play an important role in enhancing the dissolution properties for the poorly water-soluble drugs. As the pore size between 3.7 and 16.0 nm increased, the dissolution rate of CEL from FMS gradually increased. - Highlights: • Exploitation of 3D cubic mesoporous silica (16 nm) as a carrier was completed. • The release rate of CEL increased on increasing the pore size of carriers. • The crystallinity

  14. Mixed body- and gaze-centered coding of proprioceptive reach targets after effector movement.

    Science.gov (United States)

    Mueller, Stefanie; Fiehler, Katja

    2016-07-01

    Previous studies demonstrated that an effector movement intervening between encoding and reaching to a proprioceptive target determines the underlying reference frame: proprioceptive reach targets are represented in a gaze-independent reference frame if no movement occurs but are represented with respect to gaze after an effector movement (Mueller and Fiehler, 2014a). The present experiment explores whether an effector movement leads to a switch from a gaze-independent, body-centered reference frame to a gaze-dependent reference frame or whether a gaze-dependent reference frame is employed in addition to a gaze-independent, body-centered reference frame. Human participants were asked to reach in complete darkness to an unseen finger (proprioceptive target) of their left target hand indicated by a touch. They completed 2 conditions in which the target hand remained either stationary at the target location (stationary condition) or was actively moved to the target location, received a touch and was moved back before reaching to the target (moved condition). We dissociated the location of the movement vector relative to the body midline and to the gaze direction. Using correlation and regression analyses, we estimated the contribution of each reference frame based on horizontal reach errors in the stationary and moved conditions. Gaze-centered coding was only found in the moved condition, replicating our previous results. Body-centered coding dominated in the stationary condition while body- and gaze-centered coding contributed equally strong in the moved condition. Our results indicate a shift from body-centered to combined body- and gaze-centered coding due to an effector movement before reaching towards proprioceptive targets. PMID:27157885

  15. Potassium body burdens in occupational users of egyptian nuclear research center

    International Nuclear Information System (INIS)

    A simple calibration procedure for inshas whole body counter for evaluating total potassium have been adopted. More than 120 egyptian employee in the nuclear research center (N. R. C.) were studied for their total body potassium (TBK). The potassium values were found to have an average of 2.85 gm k kg-1 body weight for males and 2.62 gm k kg-1 for females, which is higher than the recommended value given for reference man by ICRP. The TBK varied directly with body build index and is slightly dependent.7 figs., 1 tab

  16. Three-body scattering problem in the fixed center approximation: the case of attraction

    CERN Document Server

    Kudryavtsev, Alexander E; Romanov, Alexander I

    2016-01-01

    We study scattering of a light particle on a bound pair of heavy particles (e.g., the deuteron) within the fixed center approximation in the case of light-heavy attraction, solving the integral equation for the three-body Green's function both in the coordinate and in the momentum space. The results for the three-body scattering amplitude appear to be ambiguous -- they depend on a single real parameter. This parameter may be fixed by a three-body input, e.g., the three-body scattering length. We also solve the integral equation for the three-body Green function in the momentum space, introducing a finite cut-off. We show that all three approaches are equivalent. We also discuss how our approach to the problem matches with the introduction of three-body contact interaction as done by other authors.

  17. Ion-beam-induced magnetic and structural phase transformation of Ni-stabilized face-centered-cubic Fe films on Cu(100)

    Energy Technology Data Exchange (ETDEWEB)

    Gloss, Jonas [Institute of Applied Physics, Vienna University of Technology, 1040 Vienna (Austria); Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic); Shah Zaman, Sameena [Institute of Applied Physics, Vienna University of Technology, 1040 Vienna (Austria); Comsats Institute of Information Technology, Park Road, 44000 Islamabad (Pakistan); Jonner, Jakub; Novotny, Zbynek; Schmid, Michael [Institute of Applied Physics, Vienna University of Technology, 1040 Vienna (Austria); Varga, Peter [Institute of Applied Physics, Vienna University of Technology, 1040 Vienna (Austria); CEITEC BUT, Brno University of Technology, Technická 10, 616 00 Brno (Czech Republic); Urbánek, Michal [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic); CEITEC BUT, Brno University of Technology, Technická 10, 616 00 Brno (Czech Republic)

    2013-12-23

    Metastable face-centered cubic (fcc) Fe/Cu(100) thin films are good candidates for ion-beam magnetic patterning due to their magnetic transformation upon ion-beam irradiation. However, pure fcc Fe films undergo spontaneous transformation when their thickness exceeds 10 ML. This limit can be extended to approximately 22 ML by deposition of Fe at increased CO background pressures. We show that much thicker films can be grown by alloying with Ni for stabilizing the fcc γ phase. The amount of Ni necessary to stabilize nonmagnetic, transformable fcc Fe films in dependence on the residual background pressure during the deposition is determined and a phase diagram revealing the transformable region is presented.

  18. Ion-beam-induced magnetic and structural phase transformation of Ni-stabilized face-centered-cubic Fe films on Cu(100)

    International Nuclear Information System (INIS)

    Metastable face-centered cubic (fcc) Fe/Cu(100) thin films are good candidates for ion-beam magnetic patterning due to their magnetic transformation upon ion-beam irradiation. However, pure fcc Fe films undergo spontaneous transformation when their thickness exceeds 10 ML. This limit can be extended to approximately 22 ML by deposition of Fe at increased CO background pressures. We show that much thicker films can be grown by alloying with Ni for stabilizing the fcc γ phase. The amount of Ni necessary to stabilize nonmagnetic, transformable fcc Fe films in dependence on the residual background pressure during the deposition is determined and a phase diagram revealing the transformable region is presented

  19. Synthesis of ultrathin face-centered-cubic Au@Pt and Au@Pd core-shell nanoplates from hexagonal-close-packed Au square sheets

    KAUST Repository

    Fan, Zhanxi

    2015-03-17

    The synthesis of ultrathin face-centered-cubic (fcc) Au@Pt rhombic nanoplates is reported through the epitaxial growth of Pt on hexagonal-close-packed (hcp) Au square sheets (AuSSs). The Pt-layer growth results in a hcp-to-fcc phase transformation of the AuSSs under ambient conditions. Interestingly, the obtained fcc Au@Pt rhombic nanoplates demonstrate a unique (101)f orientation with the same atomic arrangement extending from the Au core to the Pt shell. Importantly, this method can be extended to the epitaxial growth of Pd on hcp AuSSs, resulting in the unprecedented formation of fcc Au@Pd rhombic nanoplates with (101)f orientation. Additionally, a small amount of fcc (100)f-oriented Au@Pt and Au@Pd square nanoplates are obtained with the Au@Pt and Au@Pd rhombic nanoplates, respectively. We believe that these findings will shed new light on the synthesis of novel noble bimetallic nanostructures. Phase change: Ultrathin Au@Pt and Au@Pd core-shell nanoplates were prepared from Au square sheets. A phase transformation from hexagonal close-packed (hcp) to face-centered cubic (fcc) is observed upon coating the hcp Au square sheets with Pt or Pd under ambient conditions. The prepared fcc Au@Pt and Au@Pd rhombic nanoplates demonstrate unique (101)f orientation (picture shows a typical fcc Au@Pt rhombic nanoplate). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Eating behavior and body image perception of pregnant women attending a high-risk outpatient center

    OpenAIRE

    Raquel Guimarães Nobre; Ana Vaneska Passos Meireles; Julyanne Torres Frota; Raphael Marques de Miranda Costa; Vanessa Fernandes Coutinho; Maria Miriam da Cunha Melo Garcia; Luciana Catunda Brito

    2014-01-01

    Objective: To investigate the eating behavior and body image perception in pregnant women attending a high-risk outpatient center. Methods: A quantitative, cross-sectional, observational study conducted with 28 overweight pregnant women attending the first consultation in the nutrition outpatient center of a maternity hospital in Fortaleza-CE, from December 2010 to February 2011. It has been used a pre-established form containing data on the characterization of the sample (socioeconomic, obst...

  1. Thermodynamics of the formation of face-centered-cubic silicon nanocrystals in silicon-rich SiC thin films annealed using rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Zeng Yuheng, E-mail: yuhengzeng@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Chen Xiaobo; Cheng Qiang; Zhao Junhua; Song Weijie [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Dai Ning, E-mail: daining@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Fcc-structured Si-NCs were formed in the surface layer of SiC-matrix thin film. Black-Right-Pointing-Pointer Nucleation of fcc-structured Si-NCs was demonstrated using thermodynamics. Black-Right-Pointing-Pointer Gibbs free energy and surface energy determined the structure of Si-NC nuclei. Black-Right-Pointing-Pointer Nano-induced pressure was helpful for the nucleation of fcc-structured Si-NCs. Black-Right-Pointing-Pointer Formation of fcc-structured Si-NCs was unrelated to the effect of carbon-doping. - Abstract: Silicon nanocrystals (Si-NCs) in silicon carbide (SiC) matrix fabricated by rapid thermal annealing were characterized using grazing incidence X-ray diffraction and transmission electron microscopy. Two structures of Si-NCs were found in the thin films. Si-NCs in the surface layer had face-centered cubic (fcc) structure, whereas those in the inner layer had cubic diamond (cd) structure. The thermodynamics for the formation of fcc-structured Si-NCs was demonstrated. We suggested that two main factors, Gibbs free energy per atom and surface energy, determined what structure of Si-NC nucleus to be formed. Specifically, reducing the Gibbs free energy per atom of fcc-Si crystal and lowering the surface energy of fcc-Si crystal would be helpful for the formation of fcc-structured Si-NC nucleus. In addition, the effects of carbon and substrate on the formation of Si-NCs were discussed. The work suggested that fcc-structured Si-NCs were readily generated in the surface layer of Si-rich SiC thin films.

  2. Muscle contributions to fore-aft and vertical body mass center accelerations over a range of running speeds

    OpenAIRE

    Hamner, Samuel R.; Delp, Scott L.

    2012-01-01

    Running is a bouncing gait in which the body mass center slows and lowers during the first half of the stance phase; the mass center is then accelerated forward and upward into flight during the second half of the stance phase. Muscle-driven simulations can be analyzed to determine how muscle forces accelerate the body mass center. However, muscle-driven simulations of running at different speeds have not been previously developed, and it remains unclear how muscle forces modulate mass center...

  3. Eating behavior and body image perception of pregnant women attending a high-risk outpatient center

    Directory of Open Access Journals (Sweden)

    Raquel Guimarães Nobre

    2014-06-01

    Full Text Available Objective: To investigate the eating behavior and body image perception in pregnant women attending a high-risk outpatient center. Methods: A quantitative, cross-sectional, observational study conducted with 28 overweight pregnant women attending the first consultation in the nutrition outpatient center of a maternity hospital in Fortaleza-CE, from December 2010 to February 2011. It has been used a pre-established form containing data on the characterization of the sample (socioeconomic, obstetric, and nutritional, the BES (Binge Eating Scale to assess binge eating and BSQ (Body Shape Questionnaire to assess the severity or absence of body image disorder. The variables were presented as mean ± standard deviation and simple frequency and percentage. The Pearson’s correlation was used to verify the relation between body image and binge eating, considering p <0.05. Results: The pregnant women studied had a mean age of 29.4 ± 6.3 years and mean gestational age of 24.6 ± 8.2 weeks. It was found a prevalence of 71.5% (n=20 of body image disorder and 17.8% (n=5 of binge eating. It was also observed a direct and significant correlation between the body image perception and the degree of binge eating (r=0.4358, p=0.020. Conclusion: The high rate of body image disorder positively related to a significant binge eating indicates an unfavorable adjustment of this group of pregnant women to alterations in weight and body shape and size, which are inherent to pregnancy, standing out as group that needs special attention by the professional team. doi:10.5020/18061230.2014.p256

  4. Interactions of prismatic dislocation loops with free surfaces in thin foils of body-centered cubic iron

    Czech Academy of Sciences Publication Activity Database

    Fikar, Jan; Gröger, Roman

    2015-01-01

    Roč. 99, OCT (2015), s. 392-401. ISSN 1359-6454 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068; GA MŠk(CZ) EE2.3.20.0214 Institutional support: RVO:68081723 Keywords : Dislocation loop * Dislocation mobility * Dislocation theory * Irradiation effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.465, year: 2014

  5. Effect of expansion/shrinkage of crystal lattice on hydrogen isotopes behavior in body-centered cubic metals

    International Nuclear Information System (INIS)

    Effects of shrinkage/expansion of crystal lattice on the diffusivity and the solubility of hydrogen isotopes in bcc-metals were investigated. In order to obtain systematic and detailed information, an energy was decomposed into two parts: potential-energy-of-hydrogen and elastic-energy. Both of the migration barrier and the solution energy of hydrogen were increased by lattice shrinkage and were decreased by lattice expansion, basically. Change of migration barrier was mainly subject to that of elastic-energy. However, when the crystal lattice was strongly shrunk, e.g. 5% shrinkage, the migration barrier was decreased due to an abrupt decrease of potential-energy-of-hydrogen, which resulted from increasing interaction between the hydrogen atom and the second-nearest neighbor metal atoms. (author)

  6. Activated states for cross-slip at screw dislocation intersections in face-centered cubic nickel and copper via atomistic simulation

    International Nuclear Information System (INIS)

    We extend our recent simulation studies where a screw dislocation in face-centered cubic (fcc) Ni was found to spontaneously attain a low energy partially cross-slipped configuration upon intersecting a forest dislocation. Using atomistic (molecular statics) simulations with embedded atom potentials, we evaluated the activation barrier for a dislocation to transform from fully residing on the glide plane to fully residing on a cross-slip plane intersecting a forest dislocation in both Ni and Cu. The activation energies were obtained by determining equilibrium configurations (energies) when variable pure tensile or compressive stresses were applied along the [1 1 1] direction on the partially cross-slipped state. We show that the activation energy is a factor of 2-5 lower than that for cross-slip in isolation via the Escaig process. The cross-slip activation energies obtained at the intersection in Cu were in reasonable accord with the experimentally determined cross-slip activation energy for Cu. Further, the activation barrier for cross-slip at these intersections was shown to be linearly proportional to (d/b)[ln(√(3)d/b)]1/2, as in the Escaig process, where d is the Shockley partial dislocation spacing and b is the Burgers vector of the screw dislocation. These results suggest that cross-slip should be preferentially observed at selected screw dislocation intersections in fcc materials.

  7. Activated states for cross-slip at screw dislocation intersections in face-centered cubic nickel and copper via atomistic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Rao, S.I., E-mail: satish.rao@wpafb.af.mil [UES Inc., 4401 Dayton-Xenia Road, Dayton, OH 45432-1894 (United States); Dimiduk, D.M. [Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLLM Wright-Patterson AFB, OH 45433-7817 (United States); El-Awady, J.A. [UTC, Dayton, OH 45432 (United States); Parthasarathy, T.A. [UES Inc., 4401 Dayton-Xenia Road, Dayton, OH 45432-1894 (United States); Uchic, M.D.; Woodward, C. [Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLLM Wright-Patterson AFB, OH 45433-7817 (United States)

    2010-10-15

    We extend our recent simulation studies where a screw dislocation in face-centered cubic (fcc) Ni was found to spontaneously attain a low energy partially cross-slipped configuration upon intersecting a forest dislocation. Using atomistic (molecular statics) simulations with embedded atom potentials, we evaluated the activation barrier for a dislocation to transform from fully residing on the glide plane to fully residing on a cross-slip plane intersecting a forest dislocation in both Ni and Cu. The activation energies were obtained by determining equilibrium configurations (energies) when variable pure tensile or compressive stresses were applied along the [1 1 1] direction on the partially cross-slipped state. We show that the activation energy is a factor of 2-5 lower than that for cross-slip in isolation via the Escaig process. The cross-slip activation energies obtained at the intersection in Cu were in reasonable accord with the experimentally determined cross-slip activation energy for Cu. Further, the activation barrier for cross-slip at these intersections was shown to be linearly proportional to (d/b)[ln({radical}(3)d/b)]{sup 1/2}, as in the Escaig process, where d is the Shockley partial dislocation spacing and b is the Burgers vector of the screw dislocation. These results suggest that cross-slip should be preferentially observed at selected screw dislocation intersections in fcc materials.

  8. Cubic Equation

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    At the beginning of 16th century, mathematicians found it easy to solve equations of the first degree(linear equations, involving x) and of the second degree(quadratic equatiorts, involving x2). Equations of the third degree(cubic equations, involving x3)defeated them.

  9. Analysis of the twin spacing and grain size effects on mechanical properties in hierarchically nanotwinned face-centered cubic metals based on a mechanism-based plasticity model

    Science.gov (United States)

    Zhu, Linli; Qu, Shaoxing; Guo, Xiang; Lu, Jian

    2015-03-01

    Hierarchical twin lamellae in polycrystalline face-centered cubic (fcc) metals possess a possibility to achieve higher strength with keeping an acceptable elongation. The present work is concerned with the analysis of twin spacing and grain size-dependent plastic performance in hierarchically nanotwinned fcc metals using a generalized strain-gradient plasticity model. The dislocation density-based physical model for constitutive description of nanotwinned fcc metals is expanded for the hierarchical structures of nanotwins. The strengthening mechanism and the failure behavior in these hierarchical nanostructures are studied to evaluate the strength and ductility. Moreover, the transition twin spacing between the strengthening and softening is obtained in different order of twin lamellae. A dislocation-based model on nucleating deformation twins is presented to predict the critical twin spacing in the lowest twin lamellae for generating the subordinate twin lamellae. Our simulation results demonstrate that the existence of the hierarchical nanotwins gives rise to a significant enhancement in the strength, and the resulting global flow stresses are sensitive to the twin spacings of the hierarchical twin lamellae and the grain size. Two softening stages are observed with variation of twin spacing, and the relevant transition twin spacing depends on the microstructural size in hierarchically nanotwinned metals. We further find that the predicted failure strain decreases with decreasing the twin spacing, which is quite different from the case of the individually nanotwinned fcc metals. The critical twin spacing for generating subordinate twins also depends on the twin spacing of superordinate twin lamellae and the grain size. These findings suggest that the high yield strength and good ductility can be achieved by optimizing the grain size and the twin spacings in the hierarchical twins.

  10. Nonlinear Analysis and Preliminary Testing Results of a Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Rouse, Marshall; Lovejoy, Andrew E.; Wu, Hsi-Yung T.

    2015-01-01

    A large test article was recently designed, analyzed, fabricated, and successfully tested up to the representative design ultimate loads to demonstrate that stiffened composite panels with through-the-thickness reinforcement are a viable option for the next generation large transport category aircraft, including non-conventional configurations such as the hybrid wing body. This paper focuses on finite element analysis and test data correlation of the hybrid wing body center section test article under mechanical, pressure and combined load conditions. Good agreement between predictive nonlinear finite element analysis and test data is found. Results indicate that a geometrically nonlinear analysis is needed to accurately capture the behavior of the non-circular pressurized and highly-stressed structure when the design approach permits local buckling.

  11. Finite Element Analysis and Test Results Comparison for the Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Rouse, Marshall; Lovejoy, Andrew E.

    2016-01-01

    This report documents the comparison of test measurements and predictive finite element analysis results for a hybrid wing body center section test article. The testing and analysis efforts were part of the Airframe Technology subproject within the NASA Environmentally Responsible Aviation project. Test results include full field displacement measurements obtained from digital image correlation systems and discrete strain measurements obtained using both unidirectional and rosette resistive gauges. Most significant results are presented for the critical five load cases exercised during the test. Final test to failure after inflicting severe damage to the test article is also documented. Overall, good comparison between predicted and actual behavior of the test article is found.

  12. Towards Interactive Medical Content Delivery Between Simulated Body Sensor Networks and Practical Data Center.

    Science.gov (United States)

    Shi, Xiaobo; Li, Wei; Song, Jeungeun; Hossain, M Shamim; Mizanur Rahman, Sk Md; Alelaiwi, Abdulhameed

    2016-10-01

    With the development of IoT (Internet of Thing), big data analysis and cloud computing, traditional medical information system integrates with these new technologies. The establishment of cloud-based smart healthcare application gets more and more attention. In this paper, semi-physical simulation technology is applied to cloud-based smart healthcare system. The Body sensor network (BSN) of system transmit has two ways of data collection and transmission. The one is using practical BSN to collect data and transmitting it to the data center. The other is transmitting real medical data to practical data center by simulating BSN. In order to transmit real medical data to practical data center by simulating BSN under semi-physical simulation environment, this paper designs an OPNET packet structure, defines a gateway node model between simulating BSN and practical data center and builds a custom protocol stack. Moreover, this paper conducts a large amount of simulation on the real data transmission through simulation network connecting with practical network. The simulation result can provides a reference for parameter settings of fully practical network and reduces the cost of devices and personnel involved. PMID:27562482

  13. Influence of a hydrostatic pressure on the diffusion in metals having a cubic structure

    International Nuclear Information System (INIS)

    In view of obtaining informations on the structure of vacancies. We have determined, by diffusion experiments under high pressure, the activation volumes for self diffusion in different face centered cubic metals: silver, gold, copper, aluminium and in body centered cubic uranium (gamma phase). Activation volumes for noble metals diffusion in aluminium have also been investigated. The experimental results on gold, silver and copper are in good agreement with most of the theoretical models. The estimated activation volume for gamma uranium seems to indicate a vacancy mechanism.The results on aluminium for both self and impurity diffusion agree quite well with Friedel's theoretical predictions

  14. Kinematics of the Hip and Body Center of Mass in Front Crawl

    Science.gov (United States)

    Fernandes, Ricardo J.; Ribeiro, João; Figueiredo, Pedro; Seifert, Ludovic; Vilas-Boas, João Paulo

    2012-01-01

    The kinematic profiles of the hip and center of mass in front crawl swimming were compared to quantify the error of using a fixed body point to assess intracyclic velocity variations at moderate intensity exercise. The practical goal was to provide a useful tool, easy and fast to assess, and to use as feedback, for assessing swimming efficiency. Sixteen swimmers performed an intermittent incremental protocol that allowed assessing the individual anaerobic threshold velocity. One complete stroke cycle was analysed at the step intensity corresponding to each swimmer’s anaerobic threshold. The subjects were videotaped in the sagittal plane using a double camera set-up for two-dimensional kinematical analyses. The hip and the center of mass presented similar mean velocity and displacement values, being highly related to both parameters. However, the hip reflects the center of mass forward velocity and horizontal displacement with 7.54% and 3.24% associated error, respectively. Differences between hip and center of mass were observed for intracyclic velocity variations (0.19±0.05 and 0.25±0.08, respectively, for a p<0.001), and the negative mean error value found (−0.06) evidenced a tendency of the hip to overestimate the center of mass velocity variation. It is possible to conclude that the hips forward movements might provide a good estimate of the swimmer’s horizontal velocity and displacement that is relevant for diagnostic purposes, especially to assess swimming efficiency through the intracyclic velocity variations. Nevertheless, the hip point error magnitude should be taken into consideration in data interpretation. PMID:23486784

  15. Effect of lattice thermal vibrations on dechanneling of positrons in disordered cubic metals

    International Nuclear Information System (INIS)

    Planar dechanneling of positrons due to lattice disorder has been investigated for disordered cubic metals due to point defects by self interstitials in face-centered and body-centered cubic metals, octahedral (OH), dumbbell configurations (DBC) and body-centered interstitial (BCI) which may occur due to irradiation processes. The positron incident energy range is (25-100) MeV in the planar direction (100). The calculations included dechanneling probability , and dechanneling coefficient. The effect of lattice thermal vibration was considered by executing the calculations for static lattice and for lattice at temperatures 400,500 and 600 degree k according to Debye approximation in lattice thermal vibrations, the net planar potential at channel center is slightly higher at higher temperatures. The effect of anharmonic terms on the planar channeling potential was taken into consideration where new bound states has been found and its effect in static lattice is slightly higher than that at higher temperatures for the calculated dechanneling coefficient.

  16. Solvothermal synthesis and tailored upconversion emission of monodisperse ultrasmall face-centered cubic Sr{sub 2}YF{sub 7} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Ma Mo [Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Institute of Modern Physics, Faculty of Material and Photoelectronic Physics, Xiangtan University, Xiangtan 411105 (China); Xu Changfu, E-mail: xcf@xtu.edu.cn [Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Institute of Modern Physics, Faculty of Material and Photoelectronic Physics, Xiangtan University, Xiangtan 411105 (China); Yang Liwen; Yang Qibin; Lin Jianguo [Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University, Xiangtan 411105 (China); Institute of Modern Physics, Faculty of Material and Photoelectronic Physics, Xiangtan University, Xiangtan 411105 (China)

    2012-06-05

    Highlights: Black-Right-Pointing-Pointer Monodisperse ultrasmall Sr{sub 2}YF{sub 7} nanocrystals (sub-10 nm) were synthesized. Black-Right-Pointing-Pointer Sr{sub 2}YF{sub 7} nanocrystals are of fcc structure with the cell parameter a = 5.704 Angstrom-Sign . Black-Right-Pointing-Pointer Intense upconversion can be obtained in Ln{sup 3+} doped Sr{sub 2}YF{sub 7} nanocrystals. Black-Right-Pointing-Pointer ET from Tm{sup 3+} to Er{sup 3+} leads three-photon process, which renders the 523 nm emission. - Abstract: Monodisperse Sr{sub 2}YF{sub 7} nanocrystals with the size of sub-10 nm were synthesized via a solvothermal method by using oleate as a capping ligand. X-ray diffraction and transmission electron microscopy assays reveal that the as-synthesized Sr{sub 2}YF{sub 7} nanocrystals are face-centered cubic structure with the cell parameter a = 5.704 Angstrom-Sign . Intense upconversion luminescence can be observed in Er{sup 3+}/Yb{sup 3+} and Tm{sup 3+}/Yb{sup 3+} codoped Sr{sub 2}YF{sub 7} nanocrystals under the excitation of a 980 nm laser and near-white-color emission can be obtained in Er{sup 3+}/Tm{sup 3+}/Yb{sup 3+} tri-doped Sr{sub 2}YF{sub 7} nanocrystals. Energy transfer (ET) from Yb{sup 3+} to Er{sup 3+} and Tm{sup 3+} is mainly responsible to pump Er{sup 3+} and Tm{sup 3+} from the ground state to higher states. In Er{sup 3+}/Tm{sup 3+}/Yb{sup 3+} tri-doped Sr{sub 2}YF{sub 7} nanocrystals, ET from Tm{sup 3+} to Er{sup 3+} leads average three-photon process, which renders the 523 nm emission.

  17. Body-Centered Orthorhombic C_{16}: A Novel Topological Node-Line Semimetal.

    Science.gov (United States)

    Wang, Jian-Tao; Weng, Hongming; Nie, Simin; Fang, Zhong; Kawazoe, Yoshiyuki; Chen, Changfeng

    2016-05-13

    We identify by ab initio calculations a novel topological semimetal carbon phase in all-sp^{2} bonding networks with a 16-atom body-centered orthorhombic unit cell, termed bco-C_{16}. Total-energy calculations show that bco-C_{16} is comparable to solid fcc-C_{60} in energetic stability, and phonon and molecular dynamics simulations confirm its dynamical stability. This all-sp^{2} carbon allotrope can be regarded as a three-dimensional modification of graphite, and its simulated x-ray diffraction (XRD) pattern matches well a previously unexplained diffraction peak in measured XRD spectra of detonation and chimney soot, indicating its presence in the specimen. Electronic band structure calculations reveal that bco-C_{16} is a topological node-line semimetal with a single nodal ring. These findings establish a novel carbon phase with intriguing structural and electronic properties of fundamental significance and practical interest. PMID:27232027

  18. Body-Centered Orthorhombic C16 : A Novel Topological Node-Line Semimetal

    Science.gov (United States)

    Wang, Jian-Tao; Weng, Hongming; Nie, Simin; Fang, Zhong; Kawazoe, Yoshiyuki; Chen, Changfeng

    2016-05-01

    We identify by ab initio calculations a novel topological semimetal carbon phase in all-s p2 bonding networks with a 16-atom body-centered orthorhombic unit cell, termed bco-C16. Total-energy calculations show that bco-C16 is comparable to solid fcc-C60 in energetic stability, and phonon and molecular dynamics simulations confirm its dynamical stability. This all-s p2 carbon allotrope can be regarded as a three-dimensional modification of graphite, and its simulated x-ray diffraction (XRD) pattern matches well a previously unexplained diffraction peak in measured XRD spectra of detonation and chimney soot, indicating its presence in the specimen. Electronic band structure calculations reveal that bco-C16 is a topological node-line semimetal with a single nodal ring. These findings establish a novel carbon phase with intriguing structural and electronic properties of fundamental significance and practical interest.

  19. Ca+ centers for hydrogen storage: An accurate many-body study with large basis sets

    CERN Document Server

    Purwanto, Wirawan; Virgus, Yudistira; Zhang, Shiwei

    2011-01-01

    Weak H2 physisorption energies present a significant challenge to even the best correlated theoretical many-body methods. We use the phaseless auxiliary-field quantum Monte Carlo (AFQMC) method to accurately predict the binding energy of Ca+ - 4H2. Attention has recently focused on this model chemistry to test the reliability of electronic structure methods for H2 binding on dispersed alkaline earth metal centers. A modified Cholesky decomposition is implemented to realize the Hubbard-Stratonovich transformation efficiently with large Gaussian basis sets. We employ the largest correlation-consistent Gaussian type basis sets available, up to cc-pCV5Z for Ca, to accurately extrapolate to the complete basis limit. The calculated potential energy curve exhibits binding with a double-well structure.

  20. Time-varying creeping flow in an elastic shell enveloping a slender rigid center-body

    Science.gov (United States)

    Elbaz, Shai; Gat, Amir

    2014-11-01

    Flows in contact with elastic structures apply stress at the fluid-solid interface and thus create deformation fields in the solid. We study the time-varying interaction between elastic structures, subject to external forces, and an internal viscous liquid. We neglect inertia in the liquid and solid and focus on axi-symmetric annular flow enclosed by a thin-walled slender elastic shell and internally bounded by a variable cross-section rigid center-body. We employ elastic shell theory and the lubrication approximation to show that the problem is governed by the forced porous medium equation with regard to fluid pressure. We present several solutions of the flow-field and solid-deformation for various time-varying inlet pressure and external forces. The presented interaction between viscosity and elasticity may be applied to fields such as soft-robotics and micro-swimmers. Israel Science Foundation 818/13.

  1. Anisotropic cubic curvature couplings

    CERN Document Server

    Bailey, Quentin G

    2016-01-01

    To complement recent work on tests of spacetime symmetry in gravity, cubic curvature couplings are studied using an effective field theory description of spacetime-symmetry breaking. The associated mass dimension 8 coefficients for Lorentz violation studied do not result in any linearized gravity modifications and instead are revealed in the first nonlinear terms in an expansion of spacetime around a flat background. We consider effects on gravitational radiation through the energy loss of a binary system and we study two-body orbital perturbations using the post-Newtonian metric. Some effects depend on the internal structure of the source and test bodies, thereby breaking the Weak Equivalence Principle for self-gravitating bodies. These coefficients can be measured in solar-system tests, while binary-pulsar systems and short-range gravity tests are particularly sensitive.

  2. Muscle contributions to fore-aft and vertical body mass center accelerations over a range of running speeds.

    Science.gov (United States)

    Hamner, Samuel R; Delp, Scott L

    2013-02-22

    Running is a bouncing gait in which the body mass center slows and lowers during the first half of the stance phase; the mass center is then accelerated forward and upward into flight during the second half of the stance phase. Muscle-driven simulations can be analyzed to determine how muscle forces accelerate the body mass center. However, muscle-driven simulations of running at different speeds have not been previously developed, and it remains unclear how muscle forces modulate mass center accelerations at different running speeds. Thus, to examine how muscles generate accelerations of the body mass center, we created three-dimensional muscle-driven simulations of ten subjects running at 2.0, 3.0, 4.0, and 5.0m/s. An induced acceleration analysis determined the contribution of each muscle to mass center accelerations. Our simulations included arms, allowing us to investigate the contributions of arm motion to running dynamics. Analysis of the simulations revealed that soleus provides the greatest upward mass center acceleration at all running speeds; soleus generates a peak upward acceleration of 19.8m/s(2) (i.e., the equivalent of approximately 2.0 bodyweights of ground reaction force) at 5.0m/s. Soleus also provided the greatest contribution to forward mass center acceleration, which increased from 2.5m/s(2) at 2.0m/s to 4.0m/s(2) at 5.0m/s. At faster running speeds, greater velocity of the legs produced larger angular momentum about the vertical axis passing through the body mass center; angular momentum about this vertical axis from arm swing simultaneously increased to counterbalance the legs. We provide open-access to data and simulations from this study for further analysis in OpenSim at simtk.org/home/nmbl_running, enabling muscle actions during running to be studied in unprecedented detail. PMID:23246045

  3. Person-centered osteopathic practice: patients’ personality (body, mind, and soul) and health (ill-being and well-being)

    OpenAIRE

    Fahlgren, Elin; Nima, Ali A.; Archer, Trevor; Garcia, Danilo

    2015-01-01

    Background. Osteopathic philosophy and practice are congruent with the biopsychosocial model, a patient-centered approach when treating disease, and the view of the person as a unity (i.e., body, mind, and soul). Nevertheless, a unity of being should involve a systematic person-centered understanding of the patient’s personality as a biopsychosociospiritual construct that influences health (i.e., well-being and ill-being). We suggest Cloninger’s personality model, comprising temperament (i.e....

  4. Crystal polymorphism of (μ4-O)-body centered adamantanoid Cu(II) complexes

    Science.gov (United States)

    Olijnyk, V.; Zarychta, B.

    2016-02-01

    Two novel polymorphs of [Cu4(μ4-O)(μ-Cl)6(DASO)4], (DASO = diallyl sulfoxide; C6H10OS), rhombic (C) and triclinic (D), were obtained and examined by single crystal X-ray diffraction analysis at two temperatures, 295(2) and 100(1) K. This study, in addition to our recent work on the tetragonal (A) and trigonal (B) forms of the title compound, allowed determining the nature of polymorphism and temperature-induced phase transitions. It is stated that both the packing arrangement and the displacive transformation integrate these structures, forming the symmetrically and thermodynamically related series: A,B → C → D. The C3h → C4 distortion of Cu(II) trigonal bipyramidal coordination geometry underlies the static disorder of adamantanoid cage, resulting in the thermal order-disorder phase transition. The square-pyramidal distortion degree as well as the disorder rate may be crucial for anomalous magnetic behaviour of (μ4-O)-body centered adamantanoid Cu(II) complexes.

  5. Automated determination of the centers of vertebral bodies and intervertebral discs in CT and MR lumbar spine images

    Science.gov (United States)

    Štern, Darko; Vrtovec, Tomaž; Pernuš, Franjo; Likar, Boštjan

    2010-03-01

    The knowledge of the location of the centers of vertebral bodies and intervertebral discs is valuable for the analysis of the spine. Existing methods for the detection and segmentation of vertebrae in images acquired by computed tomography (CT) and magnetic resonance (MR) imaging are usually applicable only to a specific image modality and require prior knowledge of the location of vertebrae, usually obtained by manual identification or statistical modeling. We propose a completely automated framework for the detection of the centers of vertebral bodies and intervertebral discs in CT and MR images. The image intensity and gradient magnitude profiles are first extracted in each image along the already obtained spinal centerline and therefore contain a repeating pattern representing the vertebral bodies and intervertebral discs. Based on the period of the repeating pattern and by using a function that approximates the shape of the vertebral body, a model of the vertebral body is generated. The centers of vertebral bodies and intervertebral discs are detected by measuring the similarity between the generated model and the extracted profiles. The method was evaluated on 29 CT and 13 MR images of lumbar spine with varying number of vertebrae. The overall mean distance between the obtained and the ground truth centers was 2.8 +/- 1.9 mm, and no considerable differences were detected between the results for CT, T1-weighted MR or T2-weighted MR images, or among different vertebrae. The proposed method may therefore be valuable for initializing the techniques for the detection and segmentation of vertebrae.

  6. Body adiposity index and incident hypertension: The Aerobics Center Longitudinal Study

    OpenAIRE

    Moliner Urdiales, Diego; Artero, Enrique G.; España Romero, Vanesa; Blair, Steven N.

    2014-01-01

    Background and aim The body adiposity index (BAI) has been recently proposed as a new method to estimate the percentage of body fat. The association between BAI and hypertension risk has not been investigated yet. The aim of our study was to evaluate the ability of BAI to predict hypertension in males and females compared with traditional body adiposity measures. Methods and results The present follow-up analysis comprised 10,309 individuals (2259 females) free of hypertension fro...

  7. On Earth's Body - A New Center for the City of Alexandria Department of Parks and Recreation

    OpenAIRE

    Cheron, Jacqueline

    2010-01-01

    I have always been interested in the body/self relationship. As a former fitness instructor and new mother, I have experienced many variations of my body. I was especially interested in what happens during movement or exercise as the body and self become more aware of each other and the spaces around them. My thesis began with an investigation of the body in context to modern dance. I read several books and took a course on beginning modern dance where we practiced the basic motions an...

  8. Body Image in Young Gender Dysphoric Adults: A European Multi-Center Study.

    Science.gov (United States)

    Becker, Inga; Nieder, Timo O; Cerwenka, Susanne; Briken, Peer; Kreukels, Baudewijntje P C; Cohen-Kettenis, Peggy T; Cuypere, GrietDe; Haraldsen, Ira R Hebold; Richter-Appelt, Hertha

    2016-04-01

    The alteration of sex-specific body features and the establishment of a satisfactory body image are known to be particularly relevant for individuals with Gender Dysphoria (GD). The aim of the study was to first develop new scales and examine the psychometric properties of the Hamburg Body Drawing Scale (Appelt & Strauß 1988). For the second part of this study, the satisfaction with different body features in young GD adults before cross-sex treatment were compared to female and male controls. Data collection took place within the context of the European Network for the Investigation of Gender Incongruence (ENIGI) including 135 female-to-male (FtMs) and 115 male-to-female (MtFs) young GD adults and 235 female and 379 male age-adjusted controls. The five female and six male body feature subscales revealed good internal consistency. The ENIGI sample reported less satisfaction with overall appearance (d = 0.30) and with all of their body features than controls, but no subgroup differences for sexual orientation (FtM and MtF) and Age of Onset (FtM) were found. Body dissatisfaction was higher with regard to sex-specific body features (largest effect sizes of d = 3.21 for Genitalia in FtMs and d = 2.85 for Androgen-responsive features and genitalia in MtFs) than with those that appeared less related to the natal sex (d = 0.64 for Facial features in FtMs and d = 0.59 for Body shape in MtFs). Not only medical body modifying interventions, but also psychosocial guidance with regard to body image might be helpful for GD individuals before transitioning. PMID:25836027

  9. On the influence of asymmetry on the velocity of motion of isotherms near the thermal center of a cooled body

    Science.gov (United States)

    Vinogradov, V. V.; Tyazhel'nikova, I. L.; Vinogradova, E. P.

    2012-05-01

    A study has been made of the influence of asymmetric cooling of bodies due to the temperature difference on the surfaces, the difference in thermophysical characteristics of the media, and the geometry of the body on the velocity of motion of isotherms as they approach the thermal center. The results have been used for elucidation of the causes of certain thermophysical features appearing when continuously cast ingots solidify in horizontal continuous casting plants and when the bloom molds are replaced by slab molds in continuous ingot casting machines. An analytical expression for the displacement of the thermal center of a plate in formation of media with different thermal-diffusivity coefficients has been obtained.

  10. Novel first intagrals for the Fermi-Pasta-Ulam lattice with cubic nonlinearity and for other many-body systems in one and three dimensions

    International Nuclear Information System (INIS)

    Novel integrals of motion for the nonlinear lattice with the potential αxsup(2)+βxsup(4) are exhibited as well as for some other related many-body problems, in one dimension and also in three dimensions

  11. Social inequalities in body weight and physical activity: exploring the role of fitness centers.

    Science.gov (United States)

    McLaren, Lindsay; Rock, Melanie J; McElgunn, Jamie

    2012-03-01

    Fitness centers are a viable option for physical activity, particularly in climates with significant weather variation. Due to variation in economic and social expressions ofexclusivity, fitness centers may have some relation to social inequalities in physical inactivity and related health outcomes; thus, our objective was to explore this relation. Using publicly available data and guided by Bourdieu's theory of habitus, we classified fitness centers in Calgary, Canada, on three dimensions of exclusivity (economic, social, and appearance). We found that, although some highly exclusive centers exist, most demonstrated low exclusivity based on our dimensions. An overall contribution of centers to inequalities appears to be limited; however, caution is warranted in light of cutbacks to municipal budgets that can have an impact on publicly funded facilities. PMID:22428416

  12. Magnetic phase transitions for body-centered tetragonal FeRh{sub 1-x}Pt{sub x} system

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, Kaori; Ono, Teruo; Miyajima, Hideki E-mail: miyajima@phys.keio.ac.jp

    2001-05-01

    The magnetic phase transitions near the triple point of FeRh{sub 1-x}Pt{sub x} system with body-centered tetragonal structure were studied by means of magnetization measurement and Moessbauer spectroscopy. The composition (x) vs. temperature (T) phase diagram is determined. The triple point exists at x=0.715 and T=388 K. It is noted that the spin fluctuation plays an important role in the magnetic phase transition around the triple point.

  13. Nutrition and physical activity randomized control trial in child care centers improves knowledge, policies, and children's body mass index.

    OpenAIRE

    Alkon, A; Crowley, AA; Neelon, SE; Hill, S.; Pan, Y.; Nguyen, V.; Rose, R.; Savage, E; Forestieri, N; Shipman, L; Kotch, JB

    2014-01-01

    BACKGROUND: To address the public health crisis of overweight and obese preschool-age children, the Nutrition And Physical Activity Self Assessment for Child Care (NAP SACC) intervention was delivered by nurse child care health consultants with the objective of improving child care provider and parent nutrition and physical activity knowledge, center-level nutrition and physical activity policies and practices, and children's body mass index (BMI). METHODS: A seven-month randomized control tr...

  14. Macroscopic and bulk-controlled elastic modes in an interaction of interstitial alcali metal cations within a face-centered cubic crystalline fullerine

    International Nuclear Information System (INIS)

    The calculations in a majority of previous works for the fulleride (AqC60) crystals were performed within the framework of the rigid-lattice model, neglecting the distortion relaxation of the host fullerene (C60) crystal caused by the interstitial alkali-metal (A) cations. However, an each cation is a source of a static distoration field, and the resulting field is a superposition of such fields generated by all cations. This is a reason why the host-crystal distortions depend on the A-cations configurations, i.e. on a type of a spatial bulk distribution of interstitial cations. This paper seeks to find a functional relation between the amplitudes of the doping-induced structure-distortion waves and of statistic concentration ones. A semiphenomenological model is constructed here within the scope of statistical-thermodynamic treatment and using the lattice-statistics simulation method. In this model the effects due to the presence of q solute A cations over available interstices (per unit cell) on the statistic inherent reorientation and/or displacements of the solvent molecules from the average-lattice sites as well as on the lattice parameter a of the elastically-anysotropic cubic C60 crystal are taken into account

  15. Macroscopic and bulk-controlled elastic modes in an interaction of interstitial alcali metal cations within a face-centered cubic crystalline fullerine

    Energy Technology Data Exchange (ETDEWEB)

    Tatarenko, V.A.; Tsysman, C.L.; Oltarzhevskaya, Y.T. [Institute for Metal Physics, Kiev (Ukraine)

    1994-12-31

    The calculations in a majority of previous works for the fulleride (AqC{sub 60}) crystals were performed within the framework of the rigid-lattice model, neglecting the distoration relaxation of the host fullerene (C{sub 60}) crystal caused by the interstitial alkali-metal (A) cations. However, an each cation is a source of a static distoration field, and the resulting field is a superposition of such fields generated by all cations. This is a reason why the host-crystal distortions depend on the A-cations configurations, i.e. on a type of a spatial bulk distribution of interstitial cations. This paper seeks to find a functional relation between the amplitudes of the doping-induced structure-distortion waves and of statistic concentration ones. A semiphenomenological model is constructed here within the scope of statistical-thermodynamic treatment and using the lattice-statistics simulation method. In this model the effects due to the presence of q solute A cations over available interstices (per unit cell) on the statistic inherent reorientation and/or displacements of the solvent molecules from the average-lattice sites as well as on the lattice parameter a of the elastically-anysotropic cubic C{sub 60} crystal are taken into account.

  16. Center of inertia and coordinate transformations in the post-Newtonian charged n-body problem in gravitation

    International Nuclear Information System (INIS)

    We generalize the field theory propagator by finding a way to make it a function of some additional arbitrary parameters. Thus, it is now possible to obtain Lagrangians (which contain the propagator parameters) from field theory in a more general coordinate system than had previously been possible. We find the n-body (classical) Bazanski Lagrangian in this more general coordinate system and we give the relationship between the various coordinate systems by an n-body coordinate transformation involving the propagator parameters. We find the center of inertia for the case of the n-body Baszanski Lagrangian in the general coordinate system and find that the potential energy terms -Gm/sub i/m/sub j//r/sub i/j and e/sub i/e/sub j//r/sub i/j do not in general split equally between particles i and j as they do in the case of Bazanski coordinates. We also find the center of inertia for the case of the n-body (unchanged) post-Newtonian Lagrangian with parameterized post-Newtonian (PPN) parameters γ and β in standard coordinates, and show that the potential energy terms do split equally between a pair of particles

  17. Measurements of whole body and urine of the inhabitants of the neighbouring to the Radioactive Waste Storage Center (CADER)

    International Nuclear Information System (INIS)

    The existence of the Center of Storage of Radioactive Wastes (CADER) in the Municipality of Temascalapa, Estado de Mexico has generated restlessness among the inhabitants from it installation. In March 1998, its appeared in diverse media, notes and reports attributing illnesses and sufferings to the CADER activities. In coordination with the health authorities of the Estado de Mexico and of the Municipality of Temascalapa, the doctors of the ININ assisted people that converged to the centers. For the above-mentioned, in the period understood among the months of May to September 1998, its were carried out measurements in 338 urine samples and 45 whole-body of voluntary people of the surroundings of the CADER. This document has the purpose of presenting the information on the carried out measurements. (Author)

  18. IMPROVEMENT OF BODY SHOP MANAGING AS A PART OF VEHICLE IMPORTERS CENTER

    Directory of Open Access Journals (Sweden)

    Vasil Stamboliski

    2014-12-01

    Full Text Available The dynamic rhythm of living in today’s contemporary surroundings can not be considered without the use of personal and commercial vehicles, for transport of passengers and cargo. This means that every manufacturer in this segment, in their departments for development, find a way to increase their participation in the market. Since the race with time, for promoting new models on the market, not always is in positive relation with the profit which the manufacturer plans to achieve, issues the manufacturer’s focus in the after-sale activities. The body shop with its service, as part of the after-sale activities, brings the client satisfaction to a higher level and of course contributes to realization of higher profit of the company. The setting of the equipment and the staff management, the analysis of the number of entries and realized working hours in the body shop of an importer centre are the central topic/main subject for the author in this paper work. Finding the key factors, as well as the possibility for implementation of the key factors, would reflect increased number of entries, increased number of realized working hours and possibility for improving of the existing system of managing.

  19. Effect of Ti/Cr content on the microstructures and hydrogen storage properties of Laves phase-related body-centered-cubic solid solution alloys

    Energy Technology Data Exchange (ETDEWEB)

    Young, K., E-mail: kwo.young@basf.com [BASF/Battery Materials-Ovonic, 2983 Waterview Drive, Rochester Hills, MI 48309 (United States); Wong, D.F. [BASF/Battery Materials-Ovonic, 2983 Waterview Drive, Rochester Hills, MI 48309 (United States); Department of Chemical Engineering and Materials Science, Wayne State University, MI 48202 (United States); Wang, L. [BASF/Battery Materials-Ovonic, 2983 Waterview Drive, Rochester Hills, MI 48309 (United States)

    2015-02-15

    Highlights: • Influences of Ti/Cr to BCC to hydrogen storage properties were reported. • A new activation using hydrogen pressure at 5 MPa was developed. • A discharge capacity of 463 mA h g{sup −1} was reported on a C14(36%)/BCC(64%) alloy. • Increase in Ti/Cr increases storage capacity and decreases high-rate performance. • The high-rate performance was dominated by the surface reaction. - Abstract: A series of BCC/C14 mixed phase alloys with the chemical composition of Ti{sub 13.6+x}Zr{sub 2.1}V{sub 44}Cr{sub 13.2−x}Mn{sub 6.9}Fe{sub 2.7}Co{sub 1.4}Ni{sub 15.7}Al{sub 0.3}, x = 0, 2, 4, 6, 8, 10, and 12, was fabricated, and their structural, gaseous phase and electrochemical hydrogen storage properties were studied. Raising the maximum pressure for measuring the gaseous hydrogen storage capacity allowed these alloys to reach full activation, and the maximum discharge capacities ranged from 375 to 463 mA h g{sup −1}. As the Ti/Cr ratio in the alloy composition increased, the maximum gaseous hydrogen storage capacity improved due to the expansion in both BCC and C14 unit cells. However, reversibility decreased due to the higher stability of the hydride phase, as indicated by the lower equilibrium pressures measured for these alloys. As with most other metal hydride alloys, the electrochemical capacities measured at 50 and 4 mA g{sup −1} fell between the boundaries set by the maximum and reversible gaseous hydrogen storage capacities. The poorer high-rate dischargeability observed with higher Ti/Cr ratios was attributed to the lower surface exchange current (less catalytic). Two other negative impacts observed with higher Ti/Cr ratios in the alloy composition are poorer cycle stability and lower open-circuit voltage.

  20. Effect of Ti/Cr content on the microstructures and hydrogen storage properties of Laves phase-related body-centered-cubic solid solution alloys

    International Nuclear Information System (INIS)

    Highlights: • Influences of Ti/Cr to BCC to hydrogen storage properties were reported. • A new activation using hydrogen pressure at 5 MPa was developed. • A discharge capacity of 463 mA h g−1 was reported on a C14(36%)/BCC(64%) alloy. • Increase in Ti/Cr increases storage capacity and decreases high-rate performance. • The high-rate performance was dominated by the surface reaction. - Abstract: A series of BCC/C14 mixed phase alloys with the chemical composition of Ti13.6+xZr2.1V44Cr13.2−xMn6.9Fe2.7Co1.4Ni15.7Al0.3, x = 0, 2, 4, 6, 8, 10, and 12, was fabricated, and their structural, gaseous phase and electrochemical hydrogen storage properties were studied. Raising the maximum pressure for measuring the gaseous hydrogen storage capacity allowed these alloys to reach full activation, and the maximum discharge capacities ranged from 375 to 463 mA h g−1. As the Ti/Cr ratio in the alloy composition increased, the maximum gaseous hydrogen storage capacity improved due to the expansion in both BCC and C14 unit cells. However, reversibility decreased due to the higher stability of the hydride phase, as indicated by the lower equilibrium pressures measured for these alloys. As with most other metal hydride alloys, the electrochemical capacities measured at 50 and 4 mA g−1 fell between the boundaries set by the maximum and reversible gaseous hydrogen storage capacities. The poorer high-rate dischargeability observed with higher Ti/Cr ratios was attributed to the lower surface exchange current (less catalytic). Two other negative impacts observed with higher Ti/Cr ratios in the alloy composition are poorer cycle stability and lower open-circuit voltage

  1. An Example of Body-Centered Cubic Crystal Structure: The Atomium in Brussels as an Educative Tool for Introductory Materials Chemistry

    Science.gov (United States)

    Pinto, Gabriel

    2012-01-01

    When students are introduced to the ways in which atoms are arranged in crystal structures, transposing the textbook illustrations into three-dimensional structures is difficult for some of them. To facilitate this transition, this article describes an approach to the study of the structure of solids through a well-known monument, the Atomium in…

  2. Calculation of the stacking fault and twin boundary energies of body-centered cubic sodium metal using interaction energy between close-packed atomic rows

    International Nuclear Information System (INIS)

    A new method of calculation of the stacking fault and twin boundary energies in bcc metal is presented. This method is based on the model in which bcc crystal is built up of a bundle of close-packed atomic rows. Applying pseudopotential method, interaction energy between the atomic rows has been calculated, and then the energy of the two types of stacking fault and the energy of twin boundary in bcc sodium has been calculated. This method is found to be free from the convergence problem and superior to that formerly presented by Rao. (auth.)

  3. Tuning of the temperature window for unit-cell and pore-size enlargement in face-centered-cubic large-mesopore silicas templated by swollen block copolymer micelles.

    Science.gov (United States)

    Li, Yingyu; Yi, Jinhui; Kruk, Michal

    2015-09-01

    The unit-cell size and pore diameter as functions of temperature are investigated in the syntheses of FDU-12 silicas with face-centered cubic structure templated by Pluronic (PEO-PPO-PEO) block copolymer micelles swollen by toluene. The temperature range in which the unit-cell size and pore size strongly increase as temperature decreases is correlated with the critical micelle temperature (CMT) of the surfactant. While Pluronic F127 affords a wide range of unit-cell parameters (28-51 nm) and pore diameters (16-32 nm), it renders moderately enlarged pore sizes at 25 °C. The use of Pluronic F108 with higher CMT affords FDU-12 with very large unit-cell size (∼49 nm) and large pore diameter (27 nm) at 23 °C. Large unit-cell size (40-41 nm) and pore size (22 nm) were obtained even at 25 °C. The application of Pluronics F87 and F88 with much smaller molecular weights and higher CMTs also allows one to synthesize FDU-12 with quite large unit-cell parameters and pore sizes at room temperature. The present work demonstrates that one can judiciously select Pluronic surfactants with appropriate CMT to shift the temperature range in which the pore diameter is readily tunable. PMID:26178137

  4. An evolution from 3D face-centered-cubic ZnSnO3 nanocubes to 2D orthorhombic ZnSnO3 nanosheets with excellent gas sensing performance

    International Nuclear Information System (INIS)

    We have successfully observed the development of three-dimensional (3D) face-centered-cubic ZnSnO3 into two-dimensional (2D) orthorhombic ZnSnO3 nanosheets, which is the first observation of 2D ZnSnO3 nanostructures to date. The synthesis from 3D to 2D nanostructures is realized by the dual-hydrolysis-assisted liquid precipitation reaction and subsequent hydrothermal treatment. The time-dependent morphology indicates the transformation via a ‘dissolution–recrystallization’ mechanism, accompanied by a ‘further growth’ process. Furthermore, the 2D ZnSnO3 nanosheets consist of smaller sized nanoflakes. This further increases the special specific surface area and facilitates their application in gas sensing. The 2D ZnSnO3 nanosheets exhibit excellent gas sensing properties, especially through their ultra-fast response and recovery. When exposed to ethanol and acetone, the response rate is as fast as 0.26 s and 0.18 s, respectively, and the concentration limit can reach as low as 50 ppb of ethanol. All these results are much better than those reported so far. Our experimental results indicate an efficient approach to realize high-performance gas sensors. (paper)

  5. Behavioral effect of knee joint motion on body's center of mass during human quiet standing.

    Science.gov (United States)

    Yamamoto, Akio; Sasagawa, Shun; Oba, Naoko; Nakazawa, Kimitaka

    2015-01-01

    The balance control mechanism during upright standing has often been investigated using single- or double-link inverted pendulum models, involving the ankle joint only or both the ankle and hip joints, respectively. Several studies, however, have reported that knee joint motion during quiet standing cannot be ignored. This study aimed to investigate the degree to which knee joint motion contributes to the center of mass (COM) kinematics during quiet standing. Eight healthy adults were asked to stand quietly for 30s on a force platform. Angular displacements and accelerations of the ankle, knee, and hip joints were calculated from kinematic data obtained by a motion capture system. We found that the amplitude of the angular acceleration was smallest in the ankle joint and largest in the hip joint (ankle < knee < hip). These angular accelerations were then substituted into three biomechanical models with or without the knee joint to estimate COM acceleration in the anterior-posterior direction. Although the "without-knee" models greatly overestimated the COM acceleration, the COM acceleration estimated by the "with-knee" model was similar to the actual acceleration obtained from force platform measurement. These results indicate substantial effects of knee joint motion on the COM kinematics during quiet standing. We suggest that investigations based on the multi-joint model, including the knee joint, are required to reveal the physiologically plausible balance control mechanism implemented by the central nervous system. PMID:25248799

  6. Permutations of cubical arrays

    International Nuclear Information System (INIS)

    The structure constants of an algebra determine a cube called the cubical array associated with the algebra. The permuted indices of the cubical array associated with a finite semifield generate new division algebras. We do not not require that the algebra be finite and ask 'Is it possible to choose a basis for the algebra such any permutation of the indices of the structure constants leaves the algebra unchanged?' What are the associated algebras? Author shows that the property 'weakly quadratic' is invariant under all permutations of the indices of the corresponding cubical array and presents two algebras for which the cubical array is invariant under all permutations of the indices.

  7. Whole Body Center of Mass Estimation with Portable Sensors: Using the Statically Equivalent Serial Chain and a Kinect

    Directory of Open Access Journals (Sweden)

    Alejandro González

    2014-09-01

    Full Text Available The trajectory of the whole body center of mass (CoM is useful as a reliable metric of postural stability. If the evaluation of a subject-specific CoM were available outside of the laboratory environment, it would improve the assessment of the effects of physical rehabilitation. This paper develops a method that enables tracking CoM position using low-cost sensors that can be moved around by a therapist or easily installed inside a patient’s home. Here, we compare the accuracy of a personalized CoM estimation using the statically equivalent serial chain (SESC method and measurements obtained with the Kinect to the case of a SESC obtained with high-end equipment (Vicon. We also compare these estimates to literature-based ones for both sensors. The method was validated with seven able-bodied volunteers for whom the SESC was identified using 40 static postures. The literature-based estimation with Vicon measurements had a average error 24.9 ± 3.7 mm; this error was reduced to 12.8 ± 9.1 mm with the SESC identification. When using Kinect measurements, the literature-based estimate had an error of 118.4 ± 50.0 mm, while the SESC error was 26.6 ± 6.0 mm. The subject-specific SESC estimate using low-cost sensors has an equivalent performance as the literature-based one with high-end sensors. The SESC method can improve CoM estimation of elderly and neurologically impaired subjects by considering variations in their mass distribution.

  8. Whole Body Center of Mass Estimation with Portable Sensors: Using the Statically Equivalent Serial Chain and a Kinect

    Science.gov (United States)

    González, Alejandro; Hayashibe, Mitsuhiro; Bonnet, Vincent; Fraisse, Philippe

    2014-01-01

    The trajectory of the whole body center of mass (CoM) is useful as a reliable metric of postural stability. If the evaluation of a subject-specific CoM were available outside of the laboratory environment, it would improve the assessment of the effects of physical rehabilitation. This paper develops a method that enables tracking CoM position using low-cost sensors that can be moved around by a therapist or easily installed inside a patient's home. Here, we compare the accuracy of a personalized CoM estimation using the statically equivalent serial chain (SESC) method and measurements obtained with the Kinect to the case of a SESC obtained with high-end equipment (Vicon). We also compare these estimates to literature-based ones for both sensors. The method was validated with seven able-bodied volunteers for whom the SESC was identified using 40 static postures. The literature-based estimation with Vicon measurements had a average error 24.9 ± 3.7 mm; this error was reduced to 12.8 ± 9.1 mm with the SESC identification. When using Kinect measurements, the literature-based estimate had an error of 118.4 ± 50.0 mm, while the SESC error was 26.6 ± 6.0 mm. The subject-specific SESC estimate using low-cost sensors has an equivalent performance as the literature-based one with high-end sensors. The SESC method can improve CoM estimation of elderly and neurologically impaired subjects by considering variations in their mass distribution. PMID:25215943

  9. Center of Mass of Two or More Celestial Bodies as a Basis of Comets and «Black Holes» Mechanism

    OpenAIRE

    Eugeny F. Orlov

    2012-01-01

    The article considers the questions, arising during rendezvous of two celestial bodies with equal mass, one of which is the Earth and the consequences of such rendezvous to modern civilization, suggests the idea of centers of galaxies mass with anomalously large values of the gravitational fields, which allows to divide them into two types – material filled and hollow.

  10. Center of Mass of Two or More Celestial Bodies as a Basis of Comets and «Black Holes» Mechanism

    Directory of Open Access Journals (Sweden)

    Eugeny F. Orlov

    2012-04-01

    Full Text Available The article considers the questions, arising during rendezvous of two celestial bodies with equal mass, one of which is the Earth and the consequences of such rendezvous to modern civilization, suggests the idea of centers of galaxies mass with anomalously large values of the gravitational fields, which allows to divide them into two types – material filled and hollow.

  11. Stereotactic Body Radiotherapy for Medically Inoperable Lung Cancer: Prospective, Single-Center Study of 108 Consecutive Patients

    International Nuclear Information System (INIS)

    Purpose: To present the results of stereotactic body radiotherapy (SBRT) for medically inoperable patients with Stage I non–small-cell lung cancer (NSCLC) and contrast outcomes in patients with and without a pathologic diagnosis. Methods and Materials: Between December 2004 and October 2008, 108 patients (114 tumors) underwent treatment according to the prospective research ethics board-approved SBRT protocols at our cancer center. Of the 108 patients, 88 (81.5%) had undergone pretreatment whole-body [18F]-fluorodeoxyglucose positron emission tomography/computed tomography. A pathologic diagnosis was unavailable for 33 (28.9%) of the 114 lesions. The SBRT schedules included 48 Gy in 4 fractions or 54–60 Gy in 3 fractions for peripheral lesions and 50–60 Gy in 8–10 fractions for central lesions. Toxicity and radiologic response were assessed at the 3–6-month follow-up visits using conventional criteria. Results: The mean tumor diameter was 2.4-cm (range, 0.9–5.7). The median follow-up was 19.1 months (range, 1–55.7). The estimated local control rate at 1 and 4 years was 92% (95% confidence interval [CI], 86–97%) and 89% (95% CI, 81–96%). The cause-specific survival rate at 1 and 4 years was 92% (95% CI, 87–98%) and 77% (95% CI, 64–89%), respectively. No statistically significant difference was found in the local, regional, and distant control between patients with and without pathologically confirmed NSCLC. The most common acute toxicity was Grade 1 or 2 fatigue (53 of 108 patients). No toxicities of Grade 4 or greater were identified. Conclusions: Lung SBRT for early-stage NSCLC resulted in excellent local control and cause-specific survival with minimal toxicity. The disease-specific outcomes were comparable for patients with and without a pathologic diagnosis. SBRT can be considered an option for selected patients with proven or presumed early-stage NSCLC.

  12. Center Determination Problem for a Class of Cubic System with a Pair of Invariant Conjugate Imaginary Straight Lines%具有一对共轭复不变直线的三次系统的中心判定问题

    Institute of Scientific and Technical Information of China (English)

    桑波

    2013-01-01

    对于一类具有一对共轭复不变直线和中心-焦点型奇点的三次系统,证明它以原点为中心的充要条件是其前五阶焦点量全为零.此中心条件是通过不变代数曲线构造积分因子或对称原理得以证明.%A class of cubic systems with a pair of invariant conjugate imaginary straight lines and a center-focus type singular point,is proved to have a center at the origin if and only if the first five focal values vanish. The presence of a center at the origin is proved by constructing integrating factor formed from invariant algebraic curves or by symmetry principle.

  13. Einsteinian cubic gravity

    CERN Document Server

    Bueno, Pablo

    2016-01-01

    We drastically simplify the problem of linearizing a general higher-order theory of gravity. We reduce it to the evaluation of its Lagrangian on a particular Riemann tensor depending on two parameters, and the computation of two derivatives with respect to one of those parameters. We use our method to construct a D-dimensional cubic theory of gravity which satisfies the following properties: 1) it shares the spectrum of Einstein gravity, i.e., it only propagates a transverse and massless graviton on a maximally symmetric background; 2) the relative coefficients of the different curvature invariants involved are the same in all dimensions; 3) it is neither trivial nor topological in four dimensions. Up to cubic order in curvature, the only previously known theories satisfying the first two requirements are the Lovelock ones: Einstein gravity, Gauss-Bonnet and cubic-Lovelock. Of course, the last two theories fail to satisfy requirement 3 as they are, respectively, topological and trivial in four dimensions. We ...

  14. CFD Simulation on the J-2X Engine Exhaust in the Center-Body Diffuser and Spray Chamber at the B-2 Facility

    Science.gov (United States)

    Wang, Xiao-Yen; Wey, Thomas; Buehrle, Robert

    2009-01-01

    A computational fluid dynamic (CFD) code is used to simulate the J-2X engine exhaust in the center-body diffuser and spray chamber at the Spacecraft Propulsion Facility (B-2). The CFD code is named as the space-time conservation element and solution element (CESE) Euler solver and is very robust at shock capturing. The CESE results are compared with independent analysis results obtained by using the National Combustion Code (NCC) and show excellent agreement.

  15. Full body photography in the massive weight loss population: an inquiry to optimize patient-centered care.

    Science.gov (United States)

    Wasicek, Philip; Kaswan, Sumesh; Messing, Susan; Gusenoff, Jeffrey A

    2013-11-01

    Medical photography of body contouring patients often requires complete nudity, placing patients in a vulnerable situation. We investigated patient perspectives on full body photography in an effort to better protect the patients and enhance comfort with the photography process. Sixty-five massive weight loss patients were identified who underwent body contouring surgery with full body photography. Photographs were taken at the time of initial consult, time of marking, and postoperatively. A retrospective chart review was performed to assess body mass indices and comorbidities, and a telephone survey inquired about several aspects of the photographic process. Fifty-six (86%) patients participated. Patients were more comfortable at the time of markings (P = 0.0004) and at the postoperative session (P = 0.0009). Patients' perception of positive body image increased after body contouring surgery (P < 0.0001). Patients who reported being comfortable at their initial session had a higher body mass index (P = 0.0027). Professionalism of the staff was rated as the most important aspect of the photographic process. Patients preferring a chaperone of the same sex tended to be less comfortable with the process (P = 0.015). Most patients preferred the surgeon as the photographer (P = 0.03). Patient comfort with full body photography improves quickly as they move through the surgical process. Maintaining professionalism is the most important factor in achieving patient trust and comfort. Limiting the number of observers in the room, providing explicit details of the photography process, and having at least 1 person of the same sex in the room can optimize patient safety and comfort. PMID:23542830

  16. Mind-body skills groups for medical students: reducing stress, enhancing commitment, and promoting patient-centered care

    OpenAIRE

    Gordon, James S.

    2014-01-01

    Background For several decades, psychological stress has been observed to be a significant challenge for medical students. The techniques and approach of mind-body medicine and group support have repeatedly demonstrated their effectiveness at reducing stress and improving the quality of the education experience. Discussion Mind-Body Skills Groups provide medical students with practical instruction in and scientific evidence for a variety of techniques that reduce stress, promote self-awarenes...

  17. La di-gestión de energías en los Call Centers: entre cuerpos des-hechos y perfomances del liderazgo The Energy Absorption in Call Centers: Between Wrecked Bodies and Leadership Performance

    Directory of Open Access Journals (Sweden)

    María Inés Landa

    2012-06-01

    Full Text Available El artículo propone un estudio "en clave corporal" del universo socioproductivo de los Call Centers, centrando la mirada en la dinámica de metabolización de energías humanas que en dicho campo emergente se produce. En función de ello, se ha organizado la estrategia argumentativa en dos momentos: En primer lugar, se presenta el marco conceptual escogido para el análisis de un caso concreto: la empresa Movistar en Argentina. En segundo lugar, se describen las disposiciones energéticas diferenciales, corporales y sociales, que revela el cuadro de agentes del Call Center estudiado: teleoperador, cliente, empresa y líderes. Se concluye que el modelo de gestión de energías en los Call Centers implementa un esquema de selección y uso de los cuerpos-trabajadores original y específico. Paradójicamente, en los escenarios empresariales analizados la principal innovación tecnológica no es una máquina, sino una tecnología humana, una perfomance corporal.In this article we propose the study, from a "social body perspective", of the socio-productive universe of Call Centers, focusing on the dynamics of human energy metabolism that is produced in this emerging field. Consequently, we have organized the argumentation strategy in two moments: Firstly, we present the conceptual framework chosen for the analysis of a particular case: the telephone company Movistar in Argentina. Secondly, we describe the diferential energy dispositions, physical and social, that reveal the agents' framework of the Call Center object of study: telephone operator, client, company and leaders. We conclude that the energy management model in Call Centers implements an original and specific model of selection and use of working bodies. Paradoxically, in the analyzed business scenes the main technological innovation is not a machine but a human technology, a body performance.

  18. Assessing the Epidemiological Data and Management Methods of Body Packers Admitted to a Referral Center in Iran.

    Science.gov (United States)

    Alipour-Faz, Athena; Shadnia, Shahin; Mirhashemi, Seyyed Hadi; Peyvandi, Maryam; Oroei, Mahbobeh; Shafagh, Omid; Peyvandi, Hassan; Peyvandi, Ali Asghar

    2016-05-01

    The incidence of smuggling and transporting illegal substances by internal concealment, also known as body packing, is on the rise. The clinical approach to such patients has been changed significantly over the past 2 decades. However, despite a recorded increase in body packing in general, there are controversies in the management of these patients. We aimed to gather data regarding the demographic characteristics, treatment, and outcome of body packers, which were that referred to Loghman Hakim Hospital, Tehran, Iran.The data of all body packers admitted to Loghman Hakim Hospital during 2010 to 2014 were evaluated retrospectively. Data regarding the demographic characteristics of the patients, findings of clinical imaging, treatment, and outcome were recorded.In this study, 175 individuals with a mean age of 31 ± 10 years were assessed. The most common concealed substances were crack (37%), crystal (17%), opium (13%), and heroin (6%). According to the results of surgery and imaging (abdominal radiography or computed tomography), the most common place for concealment was stomach in 33.3% and 12% of cases, respectively. Imaging findings were normal in 18% of the individuals. Forty-eight (27%) patients underwent surgery. The main indications for surgery were clinical manifestations of toxicity (79%) and obstruction of the gastro-intestinal tract (17%). The most common surgical techniques were laparotomy and gastrotomy (50%). The mean duration of hospitalization was 3.8 ± 4 days. The mortality rate was 3%.Conservative treatment of body packers seems to be the best treatment method. Careful monitoring of the patients for possible signs and symptoms of intoxication and gastro-intestinal obstruction is strongly recommended. PMID:27175693

  19. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald;

    2016-01-01

    types. This further expands the foundations of CTT as a basis for formalisation in mathematics and computer science. We present examples to demonstrate the expressivity of our type theory, all of which have been checked using a prototype type-checker implementation, and present semantics in a presheaf......This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning with...... coinductive types. We wish to implement GDTT with decidable type-checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...

  20. Effect of a child care center-based obesity prevention program on body mass index and nutrition practices among preschool-aged children.

    Science.gov (United States)

    Natale, Ruby A; Lopez-Mitnik, Gabriela; Uhlhorn, Susan B; Asfour, Lila; Messiah, Sarah E

    2014-09-01

    This study examined the effect of an early childhood obesity prevention program on changes in Body Mass Index (BMI) z-score and nutrition practices. Eight child care centers were randomly assigned to an intervention or attention control arm. Participants were a multiethnic sample of children aged 2 to 5 years old (N = 307). Intervention centers received healthy menu changes and family-based education focused on increased physical activity and fresh produce intake, decreased intake of simple carbohydrate snacks, and decreased screen time. Control centers received an attention control program. Height, weight, and nutrition data were collected at baseline and at 3, 6, and 12 months. Analysis examined height, weight, and BMI z-score change by intervention condition (at baseline and at 3, 6, and 12 months). Pearson correlation analysis examined relationships among BMI z-scores and home activities and nutrition patterns in the intervention group. Child BMI z-score was significantly negatively correlated with the number of home activities completed at 6-month post intervention among intervention participants. Similarly, intervention children consumed less junk food, ate more fresh fruits and vegetables, drank less juice, and drank more 1% milk compared to children at control sites at 6 months post baseline. Ninety-seven percent of those children who were normal weight at baseline were still normal weight 12 months later. Findings support child care centers as a promising setting to implement childhood obesity prevention programs in this age group. PMID:24662896

  1. Fractal Symmetries: Ungauging the Cubic Code

    CERN Document Server

    Williamson, Dominic J

    2016-01-01

    Gauging is a ubiquitous tool in many-body physics. It allows one to construct highly entangled topological phases of matter from relatively simple phases and to relate certain characteristics of the two. Here we develop a gauging procedure for general submanifold symmetries of Pauli Hamiltonians, including symmetries of fractal type. We show a relation between the pre- and post- gauging models and use this to construct short range entangled phases with fractal like symmetries, one of which is mapped to the cubic code by the gauging.

  2. Home and Clinical Cardiovascular Care Center (H4C): a Framework for Integrating Body Sensor Networks and QTRU Cryptography System.

    Science.gov (United States)

    Zakerolhosseini, Ali; Sokouti, Massoud; Pezeshkian, Massoud

    2013-01-01

    Quick responds to heart attack patients before arriving to hospital is a very important factor. In this paper, a combined model of Body Sensor Network and Personal Digital Access using QTRU cipher algorithm in Wifi networks is presented to efficiently overcome these life threatening attacks. The algorithm for optimizing the routing paths between sensor nodes and an algorithm for reducing the power consumption are also applied for achieving the best performance by this model. This system is consumes low power and has encrypting and decrypting processes. It also has an efficient routing path in a fast manner. PMID:24252988

  3. Posttraumatic stress symptoms and body mass index among World Trade Center disaster-exposed smokers: A preliminary examination of the role of anxiety sensitivity.

    Science.gov (United States)

    Farris, Samantha G; Paulus, Daniel J; Gonzalez, Adam; Mahaffey, Brittain L; Bromet, Evelyn J; Luft, Benjamin J; Kotov, Roman; Zvolensky, Michael J

    2016-07-30

    Among individuals exposed to the World Trade Center (WTC) disaster on September 11, 2001, posttraumatic stress disorder (PTSD) and symptoms are both common and associated with increased cigarette smoking and body mass. However, there is little information on the specific processes underlying the relationship of PTSD symptoms with body mass. The current study is an initial exploratory test of anxiety sensitivity, the fear of internal bodily sensations, as a possible mechanism linking PTSD symptom severity and body mass index (BMI). Participants were 147 adult daily smokers (34.0% female) exposed to the WTC disaster (via rescue/recovery work or direct witness). The direct and indirect associations between PTSD symptom severity and BMI via anxiety sensitivity (total score and subscales of physical, cognitive, and social concerns) were examined. PTSD symptom severity was related to BMI indirectly via anxiety sensitivity; this effect was specific to physical concerns about the meaning of bodily sensations. Interventions focusing on anxiety sensitivity reduction (specifically addressing physical concerns about bodily sensations) may be useful in addressing elevated BMI among trauma-exposed persons. PMID:27173658

  4. Effect of surface radiation on the breakdown of steady natural convection flows in a square, air-filled cavity containing a centered inner body

    International Nuclear Information System (INIS)

    The physical model considered in the present numerical work is a square air-filled cavity cooled from below and above, with a heated square body located at the cavity center. The aim is to establish the effects of radiation interchanges amongst surfaces on the transition from steady, symmetric flows about the cavity centerline to complex periodic flows. Owing to the low temperature differences involved (1 K ≤ ΔT ≤ 5 K), the two-dimensional model is based on the Boussinesq approximation and constant thermophysical fluid properties at room temperature. The cavity walls are assumed gray and diffuse. The flow structure is investigated for various Rayleigh numbers, emissivities of the wall surfaces and sizes of the inner body. The results clearly establish the influence of surface radiation, both for steady and unsteady flows. For the geometry and thermal boundary conditions considered, the Rayleigh number for the transition to unsteady flows is considerably increased under the influence of radiation. This work underlines the difficulties in comparing experimental data and numerical solutions for gas-filled cavities partly subjected to wall heat flux boundary conditions. - Research highlights: → Heat transfer in cavities cooled from below and above with an inner heated body. → Effects of radiation on the transitions to unsteady flows are numerically studied. → The surfaces are gray and diffuse and the temperature differences are from 1 K to 5 K. → Critical Rayleigh numbers are considerably increased by radiation. → According to the thermal boundary conditions, combined analyses are required.

  5. Centro-affine hypersurface immersions with parallel cubic form

    OpenAIRE

    HILDEBRAND, Roland

    2012-01-01

    We consider non-degenerate centro-affine hypersurface immersions in R^n whose cubic form is parallel with respect to the Levi-Civita connection of the affine metric. There exists a bijective correspondence between homothetic families of proper affine hyperspheres with center in the origin and with parallel cubic form, and K\\"ochers conic omega-domains, which are the maximal connected sets consisting of invertible elements in a real semi-simple Jordan algebra. Every level surface of the omega ...

  6. High temperature x ray diffraction determination of the body-centered-cubic-face-centered-cubic transformation temperature in (Fe{sub 70}Ni{sub 30}){sub 88}Zr{sub 7}B{sub 4}Cu{sub 1} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Ipus, J. J.; McHenry, M. E. [Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Herre, P. [Institute for Metallic Materials, IFW Dresden, Helmholtzstrasse 20, Dresden D-01069 (Germany); Ohodnicki, P. [National Energy Technology Laboratory, U.S. Department of Energy, Pittsburgh, Pennsylvania 15236 (United States)

    2012-04-01

    In situ high-temperature x ray diffraction and magnetization measurements were performed on a melt-spun (Fe{sub 70}Ni{sub 30}){sub 88}Zr{sub 7}B{sub 4}Cu{sub 1} amorphous alloy to follow its structural evolution. At 728 K, a bcc-FeNi phase was observed as the primary crystallization product followed by transformation to an fcc phase {approx}773 K. During cooling to room temperature, the fcc-to-bcc transformation was not observed, and the metastable fcc-NiFe phase was retained at room temperature.

  7. TCP Performance : CUBIC, Vegas & Reno

    OpenAIRE

    Marrone, Luis Armando; Barbieri, Andrés; Robles, Matías

    2013-01-01

    At present there are different TCP versions providing different performances. In this work the three of them: Reno, CUBIC and Vegas are considered. We simulate a WAN type network analyzing the throughput and performance of these TCP variants in order to discover which of them has a better performance.

  8. Cryptographic Analysis in Cubic Time

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Seidl, H.

    2004-01-01

    The spi-calculus is a variant of the polyadic pi-calculus that admits symmetric cryptography and that admits expressing communication protocols in a precise though still abstract way. This paper shows that context-independent control flow analysis can be calculated in cubic time despite the fact ...... implementation without sacrificing precision and without making simplifying assumptions on the nature of keys....

  9. Center of buoyancy definition

    International Nuclear Information System (INIS)

    The center of buoyancy of an arbitrary shaped body is defined in analogy to the center of gravity. The definitions of the buoyant force and center of buoyancy in terms of integrals over the area of the body are converted to volume integrals and shown to have simple intuitive interpretations

  10. Cubic Matrix, Nambu Mechanics and Beyond

    OpenAIRE

    Kawamura, Yoshiharu

    2002-01-01

    We propose a generalization of cubic matrix mechanics by introducing a canonical triplet and study its relation to Nambu mechanics. The generalized cubic matrix mechanics we consider can be interpreted as a 'quantum' generalization of Nambu mechanics.

  11. Interaction Effects between Exposure to Sexually Explicit Online Materials and Individual, Family, and Extrafamilial Factors on Hong Kong High School Students' Beliefs about Gender Role Equality and Body-Centered Sexuality

    Science.gov (United States)

    To, Siu-ming; Kan, Siu-mee Iu; Ngai, Steven Sek-yum

    2015-01-01

    This study examined the interaction effects between Hong Kong adolescents' exposure to sexually explicit online materials (SEOM) and individual, family, peer, and cultural factors on their beliefs about gender role equality and body-centered sexuality. Based on a survey design with a sample of 503 high school students in Hong Kong, the results…

  12. Cubic twistorial string field theory

    Energy Technology Data Exchange (ETDEWEB)

    Berkovits, Nathan; Motl, Lubos E-mail: motl@feynman.harvard.edu

    2004-04-01

    Witten has recently proposed a string theory in twistor space whose D-instanton contributions are conjectured to compute N=4 super-Yang-Mills scattering amplitudes. An alternative string theory in twistor space was then proposed whose open string tree amplitudes reproduce the D-instanton computations of maximal degree in Witten's model. In this paper, a cubic open string field theory action is constructed for this alternative string in twistor space, and is shown to be invariant under parity transformations which exchange MHV and googly amplitudes. Since the string field theory action is gauge-invariant and reproduces the correct cubic super-Yang-Mills interactions, it provides strong support for the conjecture that the string theory correctly computes N-point super-Yang-Mills tree amplitudes. (author)

  13. Cubic Twistorial String Field Theory

    CERN Document Server

    Berkovits, N; Berkovits, Nathan; Motl, Lubos

    2004-01-01

    Witten has recently proposed a string theory in twistor space whose D-instanton contributions are conjectured to compute N=4 super-Yang-Mills scattering amplitudes. An alternative string theory in twistor space was then proposed whose open string tree amplitudes reproduce the D-instanton computations of maximal degree in Witten's model. In this paper, a cubic open string field theory action is constructed for this alternative string in twistor space, and is shown to be invariant under parity transformations which exchange MHV and googly amplitudes. Since the string field theory action is gauge-invariant and reproduces the correct cubic super-Yang-Mills interactions, it provides strong support for the conjecture that the string theory correctly computes N-point super-Yang-Mills tree amplitudes.

  14. Cubic Twistorial String Field Theory

    OpenAIRE

    Berkovits, Nathan; Motl, Lubos

    2004-01-01

    Witten has recently proposed a string theory in twistor space whose D-instanton contributions are conjectured to compute N=4 super-Yang-Mills scattering amplitudes. An alternative string theory in twistor space was then proposed whose open string tree amplitudes reproduce the D-instanton computations of maximal degree in Witten's model. In this paper, a cubic open string field theory action is constructed for this alternative string in twistor space, and is shown to be invariant under parity ...

  15. Numbers for reducible cubic scrolls

    Directory of Open Access Journals (Sweden)

    Israel Vainsencher

    2004-12-01

    Full Text Available We show how to compute the number of reducible cubic scrolls of codimension 2 in (math blackboard symbol Pn incident to the appropriate number of linear spaces.Mostramos como calcular o número de rolos cúbicos redutíveis de codimensão 2 em (math blackboard symbol Pn incidentes a espaços lineares apropriados.

  16. A conceptual model for the formation of a km-scale gabbroic body in a fossil slow spreading center (Corsica ophiolites, France)

    Science.gov (United States)

    Tribuzio, R.; Sanfilippo, A.

    2011-12-01

    The Pineto gabbroic sequence from Jurassic ophiolites of Corsica (France) represents a lower crustal section of an embryonic slow spreading center. The sequence has a thickness of ~2 km and mostly consists of troctolites and minor olivine-gabbros in its lower portion, and clinopyroxene-rich gabbros at higher stratigraphic levels. The gabbroic sequence also includes sparse olivine-rich troctolites, olivine-gabbronorites and oxide-gabbros and locally encloses up to 100 m thick bodies of mantle peridotites. Primitive troctolites occur at different stratigraphic heights, in both lower and upper portions of the sequence, thereby indicating that the building of the gabbroic section involved different primitive melt injections. Petrological variations and cooling rate estimates (from -2.2 to -1.7 °c/yr log units) as a function of the stratigraphic eight allowed us to define a conceptual model for the growth of the km-scale gabbroic sequence. The proposed conceptual model shows that the primitive melts are intruded within a lithospheric mantle, cooled by active hydrothermal circulation. These primitive melts crystallize in situ, thereby forming sills consisting of primitive troctolites. The melts residual after the formation of the troctolites migrate through focused flow and develop sills that are progressively more evolved upward. When new primitive melt injections involve the lithospheric section, these primitive melts may intrude the lithospheric mantle at different depths forming primitive troctolites at different stratigraphic levels. The melts residual after the formation of the second stage primitive troctolites migrate upward and yield a series of variably evolved sills intruding the first stage sill series. This model shows that evolved gabbroic sills derived from different primitive melt injections may be physically associated explaning the complex architecture of the gabbroic complex.

  17. Body Gravity Center Shifting and It's Training of Modern Dance Based on Sports Biomechanics Principles%基于运动生物力学原理的标准舞重心移动与训练

    Institute of Scientific and Technical Information of China (English)

    刘怀金; 邓晓东

    2012-01-01

    The key in modern dance technique is constant shifting gravity center in body, by which the whole body may move in inertia to form a moving inertial flow. And the key to forming mobile body inertia flow is that body weight transfer can be achieved by feet movement which droved by skeleton movement resulting from muscle tissue contraction under the control of the central nervous system in body trunk. In these processes, weight trans- fer can be conducted by body trunk, with mobile pivot formed by firming waist and hip, as well as balanced shift of gravity center by foot corresponding motion.%摩登舞技巧中最重要的环节是控制身体重心的不断转换,整个形体在惯性中移动,形成移动惯性流量。形体移动惯性流量的形成,关键在于身体躯干在中枢神经系统的控制下,由肌肉收缩牵引骨骼来带动腿脚移动实现重心移动到位。在此过程中,身体躯干主导着重心转移,腰胯稳固形成移动的枢纽,脚底联动实现重心的平衡转移。

  18. Tame Kernels of Pure Cubic Fields

    Institute of Scientific and Technical Information of China (English)

    Xiao Yun CHENG

    2012-01-01

    In this paper,we study the p-rank of the tame kernels of pure cubic fields.In particular,we prove that for a fixed positive integer m,there exist infinitely many pure cubic fields whose 3-rank of the tame kernel equal to m.As an application,we determine the 3-rank of their tame kernels for some special pure cubic fields.

  19. AXISYMMETRIC ELASTICITY PROBLEM OF CUBIC QUASICRYSTAL

    Institute of Scientific and Technical Information of China (English)

    ZHOU WANG-MIN; FAN TIAN-YOU

    2000-01-01

    A method for analyzing the elasticity problem of cubic quasicrystal is developed. The axisymmetric elasticity problem of cubic quasicrystal is reduced to a single higher-order partial differential equation by introducing a displacement function. As an example, the solutions of elastic field of cubic quasicrystal with a penny-shaped crack are obtained,and the stress intensity factor and strain energy release rate are determined.

  20. CLASSIFICATION OF CUBIC PARAMETERIZED HOMOGENEOUS VECTOR FIELDS

    Institute of Scientific and Technical Information of China (English)

    Karnal H.Yasir; TANG Yun

    2002-01-01

    In this paper the cubic homogeneous parameterized vector fields are studied.The classification of the phase portrait near the critical point is presented. This classification is an extension of the result given by Takens to the cubic homogeneous parameterized vector fields with six parameters.

  1. CLASSIFICATION OF CUBIC PARAMETERIZED HOMOGENEOUS VECTOR FIELDS

    Institute of Scientific and Technical Information of China (English)

    KamalH.Yasir; TNAGYun

    2002-01-01

    In this paper the cubic homogeneous parameterized vector fields are studied.The classification of the phase portrait near the critical point is presented.This classification is an extension of the result given by takens to the cubic homogeneous parameterized vector fields with six parameters.

  2. Low-temperature formation of cubic beta-PbF(2): precursor-based synthesis and first-principles phase stability study

    OpenAIRE

    Erk, Christoph; Hammerschmidt, Lukas; Andrae, Dirk; Paulus, Beate; Schlecht, Sabine

    2011-01-01

    A precursor-based approach to the cubic beta-phase of PbF(2) was developed and allowed the preparation of this high-temperature phase well below the temperature for transition from the orthorhombic alpha- to the cubic beta-phase. The formation of beta-PbF(2) from the molecular precursors Pb[Se(C(6)H(2)(CF(3))(3))](2) and Pb(C(6)H(2)(CF(3))(3))(2) is facilitated by the presence of several short Pb center dot center dot center dot F contacts in these molecules. The cubic form of PbF(2) was obta...

  3. Generalized Vaidya spacetime for cubic gravity

    Science.gov (United States)

    Ruan, Shan-Ming

    2016-03-01

    We present a kind of generalized Vaidya solution of a new cubic gravity in five dimensions whose field equations in spherically symmetric spacetime are always second order like the Lovelock gravity. We also study the thermodynamics of its spherically symmetric apparent horizon and get its entropy expression and generalized Misner-Sharp energy. Finally, we present the first law and second law hold in this gravity. Although all the results are analogous to those in Lovelock gravity, we in fact introduce the contribution of a new cubic term in five dimensions where the cubic Lovelock term is just zero.

  4. Generalized Vaidya spacetime for cubic gravity

    CERN Document Server

    Ruan, Shan-Ming

    2015-01-01

    We present a kind of generalized Vaidya solutions of a new cubic gravity in five dimensions whose field equations in spherically spacetime are always second order like the Lovelock gravity. We also study the thermodynamics of its apparent horizon and get its entropy expression and generalized Misner-Sharp energy. Finally we present the first law and second law hold in this gravity. Although all the results are analogue to those in Lovelock gravity, we in fact introduce the contribution of new cubic term in five dimensions where cubic Lovelock term is just zero.

  5. Neutron Dose Measurement Using a Cubic Moderator

    International Nuclear Information System (INIS)

    The Bonner Sphere Spectrometer (BSS), introduced In July 1960 by a research group from Rice University, Texas, is a major approach to neutron spectrum estimation. The BSS, also known as multi-sphere spectrometer, consists of a set of a different diameters polyethylene spheres, carrying a small LiI(Eu) scintillator in their center. What makes this spectrometry method such widely used, is its almost isotropic response, covering an extraordinary wide range of energies, from thermal up to even hundreds of MeVs. One of the most interesting and useful consequences of the above study is the 12'' sphere characteristics, as it turned out that the response curve of its energy dependence, have a similar shape compared with the neutron's dose equivalent as a function of energy. This inexplicable and happy circumstance makes it virtually the only monitoring device capable providing realistic neutron dose estimates over such a wide energy range. However, since the detection mechanism is not strictly related to radiation dose, one can expect substantial errors when applied to widely different source conditions. Although the original design of the BSS included a small 4mmx4mmO 6LiI(Eu) scintillator, other thermal neutron detectors has been used over the years: track detectors, activation foils, BF3 filled proportional counters, etc. In this study we chose a Boron loaded scintillator, EJ-254, as the thermal neutron detector. The neutron capture reaction on the boron has a Q value of 2.78 MeV of which 2.34 MeV is shared by the alpha and lithium particles. The high manufacturing costs, the encasement issue, the installation efficiency and the fabrication complexity, led us to the idea of replacing the sphere with a cubic moderator. This article describes the considerations, as well as the Monte-Carlo simulations done in order to examine the applicability of this idea

  6. Measurements of whole body and urine of the inhabitants of the neighbouring to the Radioactive Waste Storage Center (CADER); Mediciones de cuerpo entero y de orina de los habitantes de las poblaciones vecinas al CADER

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1998-10-15

    The existence of the Center of Storage of Radioactive Wastes (CADER) in the Municipality of Temascalapa, Estado de Mexico has generated restlessness among the inhabitants from it installation. In March 1998, its appeared in diverse media, notes and reports attributing illnesses and sufferings to the CADER activities. In coordination with the health authorities of the Estado de Mexico and of the Municipality of Temascalapa, the doctors of the ININ assisted people that converged to the centers. For the above-mentioned, in the period understood among the months of May to September 1998, its were carried out measurements in 338 urine samples and 45 whole-body of voluntary people of the surroundings of the CADER. This document has the purpose of presenting the information on the carried out measurements. (Author)

  7. The twisted cubic and camera calibration

    OpenAIRE

    Buchanan, Thomas

    1988-01-01

    We state a uniqueness theorem for camera calibration in terms of the twisted cubic. The theorem assumes the general linear model and is essentially a reformulation of Seydewitz's star generation theorem.

  8. Semisymmetric Cubic Graphs of Order 162

    Indian Academy of Sciences (India)

    Mehdi Alaeiyan; Hamid A Tavallaee; B N Onagh

    2010-02-01

    An undirected graph without isolated vertices is said to be semisymmetric if its full automorphism group acts transitively on its edge set but not on its vertex set. In this paper, we inquire the existence of connected semisymmetric cubic graphs of order 162. It is shown that for every odd prime , there exists a semisymmetric cubic graph of order 162 and its structure is explicitly specified by giving the corresponding voltage rules generating the covering projections.

  9. 2-rational Cubic Spline Involving Tension Parameters

    Indian Academy of Sciences (India)

    M Shrivastava; J Joseph

    2000-08-01

    In the present paper, 1-piecewise rational cubic spline function involving tension parameters is considered which produces a monotonic interpolant to a given monotonic data set. It is observed that under certain conditions the interpolant preserves the convexity property of the data set. The existence and uniqueness of a 2-rational cubic spline interpolant are established. The error analysis of the spline interpolant is also given.

  10. Body Fat Measurement Tools

    Science.gov (United States)

    ... Advisors Press Releases Annual Reports Donations Privacy Policy Advertising Site Map Adults Cyberkitchen Fitness Center Shape Up & Drop 10 Body Fat Lab BMI Calculator Pregnancy Weight Gain Children Assessing Childhood Obesity Pediatric BMI Assessment Overweight Assessment: A Parent's Guide ...

  11. Modified electrodes based on lipidic cubic phases.

    Science.gov (United States)

    Bilewicz, Renata; Rowiński, Paweł; Rogalska, Ewa

    2005-04-01

    The lipidic cubic phase can be characterized as a curved bilayer forming a three-dimensional, crystallographical, well-ordered structure that is interwoven by aqueous channels. It provides a stable, well-organized environment in which diffusion of both water-soluble and lipid-soluble compounds can take place. Cubic phases based on monoacylglycerols form readily and attract our interest due to their ability to incorporate and stabilize proteins. Their lyotropic and thermotropic phase behaviour has been thoroughly investigated. At hydration over 20%, lipidic cubic phases Ia3d and Pn3m are formed. The latter is stable in the presence of excess water, which is important when the cubic phase is considered as an electrode-modifying material. Due to high viscosity, the cubic phases can be simply smeared over solid substrates such as electrodes and used to host enzymes and synthetic catalysts, leading to new types of catalytically active modified electrodes as shown for the determination of cholesterol, CO(2), or oxygen. The efficiency of transport of small hydrophilic molecules within the film can be determined by voltametry using two types of electrodes: a normal-size electrode working in the linear diffusion regime, and an ultramicroelectrode working under spherical diffusion conditions. This allows determining both the concentration and diffusion coefficient of the electrochemically active probe in the cubic phase. The monoolein-based cubic phase matrices are useful for immobilizing enzymes on the electrode surface (e.g., laccases from Trametes sp. and Rhus vernicifera were employed for monitoring dioxygen). The electronic contact between the electrode and the enzyme was maintained using suitable electroactive probes. PMID:15833697

  12. Body-building

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    正In recent years, more and more people spare no pains to join in the body-building group. People begin to take part in various fitness clubs or fitness centers in their spare time. This shows body-building has become an indispensable part of many people’s life.

  13. The effects of next-to-nearest-neighbour hopping on Bose–Einstein condensation in cubic lattices

    Indian Academy of Sciences (India)

    G K Chaudhary; R Ramakumar

    2010-01-01

    In this paper, we present results of our calculations on the effects of next-to-nearest-neighbour boson hopping (′) energy on Bose–Einstein condensation in cubic lattices. We consider both non-interacting and repulsively interacting bosons moving in the lowest Bloch band. The interacting bosons are studied using Bogoliubov method. We find that the Bose condensation temperature is enhanced by increasing ′ for bosons in a simple cubic (sc) lattice and decreases for bosons in body-centred cubic (bcc) and face-centred cubic (fcc) lattices. We also find that interaction-induced depletion of the condensate is reduced for bosons in an sc lattice while it is enhanced for bosons in bcc and fcc lattices.

  14. Purely cubic action for string field theory

    Science.gov (United States)

    Horowitz, G. T.; Lykken, J.; Rohm, R.; Strominger, A.

    1986-01-01

    It is shown that Witten's (1986) open-bosonic-string field-theory action and a closed-string analog can be written as a purely cubic interaction term. The conventional form of the action arises by expansion around particular solutions of the classical equations of motion. The explicit background dependence of the conventional action via the Becchi-Rouet-Stora-Tyutin operator is eliminated in the cubic formulation. A closed-form expression is found for the full nonlinear gauge-transformation law.

  15. Structural forms of cubic BC2N

    International Nuclear Information System (INIS)

    Superhard cubic boron-carbonitrides (c-BC2N) are studied with the use of the ab initio pseudopotential density functional method. The total energy, lattice constant, bulk and shear moduli, and electronic band structures as well as the electron density of states are calculated for all the possible c-BC2N structures in an eight-atom zinc-blende-structured cubic unit cell. The results obtained provide a plausible explanation for recent experimental observations as well as a possible path to synthesis of the materials

  16. Manufacturing Techniques for SQ6 Center-depressed Double-deck Vehicle Body for Auto Transport%SQ6型凹底双层运输汽车专用车车体制造工艺

    Institute of Scientific and Technical Information of China (English)

    卜庆海; 李伟; 钟智勇

    2012-01-01

    Manufacturing techniques for SQ6 center - depressed double - deck auto transport car body are outlined, difficulties with the manufacturing processes are analyzed and relative processes are established to ensure the mass production of this type of special vehicles.%阐述了SQ6型凹底双层运输汽车专用车车体的制造工艺,分析了制造过程中的工艺难点,制定了相关的工艺措施,保证了SQ6型凹底双层运输汽车专用车的批量生产。

  17. Total body irradiation (TBI) in pediatric patients. A single-center experience after 30 years of low-dose rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmeier, Claudia; Thoennessen, Daniel; Negretti, Laura; Streller, Tino; Luetolf, Urs Martin [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Bourquin, Jean-Pierre [University Children' s Hospital Zurich (Switzerland). Dept. of Hemato-Oncology; Oertel, Susanne [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Heidelberg Univ. (Germany). Dept. of Radiation Oncology

    2010-11-15

    To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic diseases treated with total body irradiation (TBI) between 1978 and 2006. 32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics as well as treatment outcome regarding local control and overall survival were assessed. A total of 18 patients suffered from acute lymphoblastic leukemia (ALL), 5 from acute and 2 from chronic myelogenous leukemia, 1 from non-Hodgkin lymphoma, and 2 from anaplastic anemia. The cohort consisted of 15 patients referred after first remission and 13 patients with relapsed leukemia. Mean follow-up was 34 months (2-196 months) with 15 patients alive at the time of last follow-up. Eight patients died of recurrent disease, 1 of graft vs. host reaction, 2 of sepsis, and 2 patients died of a secondary malignancy. The 5-year overall survival rate (OS) was 60%. Overall survival was significantly inferior in patients treated after relapse compared to those treated for newly diagnosed leukemia (24% versus 74%; p=0.004). At the time of last follow-up, 11 patients survived for more than 36 months following TBI. Late effects (RTOG {>=}3) were pneumonitis in 1 patient, chronic bronchitis in 1 patient, cardiomyopathy in 2 patients, severe cataractogenesis in 1 patient (48 months after TBI with 10 Gy in a single dose) and secondary malignancies in 2 patients (36 and 190 months after TBI). Growth disturbances were observed in all patients treated prepubertally. In 2 patients with identical twins treated at ages 2 and 7, a loss of 8% in final height of the treated twin was observed. As severe late sequelae after TBI, we observed 2 secondary malignancies in 11 patients who survived in excess of 36 months. However, long-term morbidity is moderate following treatment with the fractionated

  18. Total body irradiation (TBI) in pediatric patients. A single-center experience after 30 years of low-dose rate irradiation

    International Nuclear Information System (INIS)

    To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic diseases treated with total body irradiation (TBI) between 1978 and 2006. 32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics as well as treatment outcome regarding local control and overall survival were assessed. A total of 18 patients suffered from acute lymphoblastic leukemia (ALL), 5 from acute and 2 from chronic myelogenous leukemia, 1 from non-Hodgkin lymphoma, and 2 from anaplastic anemia. The cohort consisted of 15 patients referred after first remission and 13 patients with relapsed leukemia. Mean follow-up was 34 months (2-196 months) with 15 patients alive at the time of last follow-up. Eight patients died of recurrent disease, 1 of graft vs. host reaction, 2 of sepsis, and 2 patients died of a secondary malignancy. The 5-year overall survival rate (OS) was 60%. Overall survival was significantly inferior in patients treated after relapse compared to those treated for newly diagnosed leukemia (24% versus 74%; p=0.004). At the time of last follow-up, 11 patients survived for more than 36 months following TBI. Late effects (RTOG ≥3) were pneumonitis in 1 patient, chronic bronchitis in 1 patient, cardiomyopathy in 2 patients, severe cataractogenesis in 1 patient (48 months after TBI with 10 Gy in a single dose) and secondary malignancies in 2 patients (36 and 190 months after TBI). Growth disturbances were observed in all patients treated prepubertally. In 2 patients with identical twins treated at ages 2 and 7, a loss of 8% in final height of the treated twin was observed. As severe late sequelae after TBI, we observed 2 secondary malignancies in 11 patients who survived in excess of 36 months. However, long-term morbidity is moderate following treatment with the fractionated

  19. Relative Lyapunov Center Bifurcations

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2014-01-01

    Relative equilibria (REs) and relative periodic orbits (RPOs) are ubiquitous in symmetric Hamiltonian systems and occur, for example, in celestial mechanics, molecular dynamics, and rigid body motion. REs are equilibria, and RPOs are periodic orbits of the symmetry reduced system. Relative Lyapunov...... center bifurcations are bifurcations of RPOs from REs corresponding to Lyapunov center bifurcations of the symmetry reduced dynamics. In this paper we first prove a relative Lyapunov center theorem by combining recent results on the persistence of RPOs in Hamiltonian systems with a symmetric Lyapunov...... center theorem of Montaldi, Roberts, and Stewart. We then develop numerical methods for the detection of relative Lyapunov center bifurcations along branches of RPOs and for their computation. We apply our methods to Lagrangian REs of the N-body problem....

  20. Dipaths and dihomotopies in a cubical complex

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth

    2005-01-01

    In the geometric realization of a cubical complex without degeneracies, a $\\Box$-set, dipaths and dihomotopies may not be combinatorial, i.e., not geometric realizations of combinatorial dipaths and equivalences. When we want to use geometric/topological tools to classify dipaths on the 1-skeleto...

  1. The cactus rank of cubic forms

    CERN Document Server

    Bernardi, Alessandra

    2011-01-01

    We prove that the smallest degree of an apolar 0-dimensional scheme to a general cubic form in $n+1$ variables is at most $2n+2$, when $n\\geq 8$, and therefore smaller than the rank of the form. When n=8 we show that the bound is sharp, i.e. the smallest degree of an apolar subscheme is 18.

  2. Some experiments with piecewise cubic interpolation

    International Nuclear Information System (INIS)

    An iterative refinement process for adjusting derivative values in the Hermite representation of a piecewise cubic function to produce visually pleasing interpolants is described. The difficulties encountered at various stages in the development of the algorithm are outlined, and future research directions are indicated. 22 figures

  3. Cubic terms from Casimir invariants in IBM

    International Nuclear Information System (INIS)

    The Xe and Ba nuclei have been shown to be good examples of O(6) dynamical symmetry of IBM. In particular, one might hope to construct cubic terms out of the Casimir invariants of the groups and subgroups of O(6), U(5) SU(3) which may give rise to triaxiality

  4. Nanodefects in ultrahard crystalline cubic boron nitride

    International Nuclear Information System (INIS)

    Cubic boron nitride (cBN), the second hardest known material after diamond, exhibits high thermal conductivity and an excellent ability to be n or p doped, which makes it a strong candidate for the next generation of high-temperature micro optical and micro electronic devices. According to recent studies, cBN exhibits a better resistance to radiation damage than diamond, which suggests potential applications in extreme radiation environments. Crystalline cBN powders of up to 0.5 mm linear size is obtained in a similar way as diamond, by catalytic conversion of hexagonal BN (hBN) to cBN at even higher pressures (> 5GPa) and temperatures (∼ 1900 K). Considering the essential role played by the nanodefects (point defects and impurities) in determining its physical properties, it is surprising how limited is the amount of published data concerning the properties of nanodefects in this material, especially by Electron Paramagnetic Resonance (EPR) spectroscopy, the most powerful method for identification and characterization of nanodefects in both insulators and semiconductors. This seems to be due mainly to the absence of natural cBN gems and the extreme difficulties in producing even mm3 sized synthetic crystals. We shall present our recent EPR studies on cBN crystalline powders, performed in a broad temperature range from room temperature (RT) down to 1.2 K on several sorts of large size cBN powder grits of yellow and amber color for industrial applications. Previous multifrequency (9.3 GHz and 95 GHz) EPR studies of brown to black cBN crystallites prepared with excess of boron, resulted in the discovery of two new types of paramagnetic point defects with different spectral properties, called the D1 and D2 centers. Our X(9.3 GHz)-band EPR investigations resulted in the observation in amber cBN crystalline powders of a spectrum with a strong temperature dependence of the lineshape. It was found that for high and low temperatures, respectively, the numerical

  5. Simulating point defects in cubic monocarbides

    International Nuclear Information System (INIS)

    Calculations have been performed on point-defect formation and migration parameters for cubic monocarbides on the basis of simple models: rigid pair bonds and an elastic continuum. However, they do not indicate how relaxation affects defect characteristics. Here the authors examine lattice relaxation around point defects by computer simulation. Atomic interaction potentials have been considered for cubic monocarbides. The volume dependence of the potential energy has been examined for ideal crystals of TiC, ZrC, HfC, VC, NbC, TaC, ThC, UC, PuC. Energy and structural characteristics have been derived for the relaxation of the lattice around vacancies and defects of substitutional type

  6. Black holes in a cubic Galileon universe

    OpenAIRE

    Babichev, Eugeny; Charmousis, Christos; Lehébel, Antoine; Moskalets, Tetiana

    2016-01-01

    We find and study the properties of black hole solutions for a subclass of Horndeski theory including the cubic Galileon term. The theory under study has shift symmetry but not reflection symmetry for the scalar field. The Galileon is assumed to have linear time dependence characterized by a velocity parameter. We give analytic 3-dimensional solutions that are akin to the BTZ solutions but with a non-trivial scalar field that modifies the effective cosmological constant. We then study the 4-d...

  7. Topological Oxide Insulator in Cubic Perovskite Structure

    OpenAIRE

    Hosub Jin; Rhim, Sonny H.; Jino Im; Freeman, Arthur J.

    2013-01-01

    The emergence of topologically protected conducting states with the chiral spin texture is the most prominent feature at the surface of topological insulators. On the application side, large band gap and high resistivity to distinguish surface from bulk degrees of freedom should be guaranteed for the full usage of the surface states. Here, we suggest that the oxide cubic perovskite YBiO3, more than just an oxide, defines itself as a new three-dimensional topological insulator exhibiting both ...

  8. Small two-component Fermi gases in a cubic box with periodic boundary conditions

    OpenAIRE

    Yin, X. Y.; Blume, D.

    2013-01-01

    The properties of two-component Fermi gases become universal if the interspecies s-wave scattering length $a_s$ and the average interparticle spacing are much larger than the range of the underlying two-body potential. Using an explicitly correlated Gaussian basis set expansion approach, we determine the eigen energies of two-component Fermi gases in a cubic box with periodic boundary conditions as functions of the interspecies s-wave scattering length and the effective range of the two-body ...

  9. Quasi-two-dimensional Bose-Einstein condensates with spatially modulated cubic-quintic nonlinearities

    International Nuclear Information System (INIS)

    We investigate exact nonlinear matter wave functions with odd and even parities in the framework of quasi-two-dimensional Bose-Einstein condensates (BECs) with spatially modulated cubic-quintic nonlinearities and harmonic potential. The existence condition for these exact solutions requires that the minimum energy eigenvalue of the corresponding linear Schroedinger equation with harmonic potential is the cutoff value of the chemical potential λ. The competition between two-body and three-body interactions influences the energy of the localized state. For attractive two-body and three-body interactions, the larger the matter wave order number n, the larger the energy of the corresponding localized state. A linear stability analysis and direct simulations with initial white noise demonstrate that, for the same state (fixed n), increasing the number of atoms can add stability. A quasi-stable ground-state matter wave is also found for repulsive two-body and three-body interactions. We also discuss the experimental realization of these results in future experiments. These results are of particular significance to matter wave management in higher-dimensional BECs. - Highlights: → 2D Bose-Einstein condensates (BECs) with spatially modulated cubic-quintic nonlinearities and the harmonic potential are discussed. → 2D exact quantized nonlinear matter wave functions with the odd and even parities are obtained. → The 2D ground-state matter wave with attractive two-body and repulsive three-body interactions is stable. → Experimental realization of our results in future experiments is proposed.

  10. Craniofacial reconstruction using rational cubic ball curves.

    Directory of Open Access Journals (Sweden)

    Abdul Majeed

    Full Text Available This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI has also been developed for practical application.

  11. Generalized fairing algorithm of parametric cubic splines

    Institute of Scientific and Technical Information of China (English)

    WANG Yuan-jun; CAO Yuan

    2006-01-01

    Kjellander has reported an algorithm for fairing uniform parametric cubic splines. Poliakoff extended Kjellander's algorithm to non-uniform case. However, they merely changed the bad point's position, and neglected the smoothing of tangent at bad point. In this paper, we present a fairing algorithm that both changed point's position and its corresponding tangent vector. The new algorithm possesses the minimum property of energy. We also proved Poliakoff's fairing algorithm is a deduction of our fairing algorithm. Several fairing examples are given in this paper.

  12. The Electric Field of a Uniformly Charged Non-Conducting Cubic Surface

    CERN Document Server

    McCreery, Kaitlin

    2016-01-01

    As an integrative and insightful example for undergraduates learning about electrostatics, we discuss how to use symmetry, Coulomb's Law, superposition, Gauss's law, and visualization to understand the electric field produced by a non-conducting cubic surface that is covered with a uniform surface charge density. We first discuss how to deduce qualitatively, using only elementary physics, the surprising fact that the electric field inside the cubic surface is nonzero and has a complex structure, pointing inwards towards the cube center from the midface of each cube and pointing outwards towards each edge and corner. We then discuss how to understand the quantitative features of the electric field by plotting an analytical expression for E along symmetry lines and on symmetry surfaces. This example would be a good choice for group problem solving in a recitation or flipped classroom.

  13. Bifurcation and Isochronicity at Infinity in a Class of Cubic Polynomial Vector Fields

    Institute of Scientific and Technical Information of China (English)

    Qin-long Wang; Yi-rong Liu

    2007-01-01

    In this paper, we study the appearance of limit cycles from the equator and isochronicity of infinity in polynomial vector fields with no singular points at infinity. We give a recursive formula to compute the singular point quantities of a class of cubic polynomial systems, which is used to calculate the first seven singular point quantities. Further, we prove that such a cubic vector field can have maximal seven limit cycles in the neighborhood of infinity. We actually and construct a system that has seven limit cycles. The positions of these limit cycles can be given exactly without constructing the Poincare cycle fields. The technique employed in this work is essentially different from the previously widely used ones. Finally, the isochronous center conditions at infinity are given.

  14. All unitary cubic curvature gravities in D dimensions

    International Nuclear Information System (INIS)

    We construct all the unitary cubic curvature gravity theories built on the contractions of the Riemann tensor in D-dimensional (anti)-de Sitter spacetimes. Our construction is based on finding the equivalent quadratic action for the general cubic curvature theory and imposing ghost and tachyon freedom, which greatly simplifies the highly complicated problem of finding the propagator of cubic curvature theories in constant curvature backgrounds. To carry out the procedure we have also classified all the unitary quadratic models. We use our general results to study the recently found cubic curvature theories using different techniques and the string generated cubic curvature gravity model. We also study the scattering in critical gravity and give its cubic curvature extensions.

  15. CALPHAD study of cubic carbide systems with Cr

    OpenAIRE

    He, Zhangting

    2015-01-01

    Cubic carbides (titanium, tantalum, niobium, and zirconium carbides) can constitute a significant proportion of so-called cubic and cermet grades, where it is added to substitute a portion of tungsten carbide. It is thus critical to understand and be able to thermodynamically model the cubic carbide systems. In order to do this, the thermodynamic descriptions of lower order systems, such as the Ti-Cr-C system, need to be well studied. To approach this goal, an extensive literature survey of t...

  16. Senior Centers

    Medline Plus

    Full Text Available ... to do as long as they can. Senior centers, adult day care, transportation, and meals programs are ... older adults to remain in their homes. Senior centers are places where older adults who live independently ...

  17. Excel Center

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Citigroup,one of the World top 500 companies,has now settled in Excel Center,Financial Street. The opening ceremony of Excel Center and the entry ceremony of Citigroup in the center were held on March 31.Government leaders of Xicheng District,the Excel CEO and the heads of Asia-Pacific Region leaders of Citibank all participated in the ceremony.

  18. Body Odor

    Science.gov (United States)

    ... Health Medical Conditions Nutrition & Fitness Emotional Health Body Odor Posted under Health Guides . Updated 29 October 2014. + ... guy has to deal with. What causes body odor? During puberty, your sweat glands become much more ...

  19. Body Hygiene

    Science.gov (United States)

    ... Home Diaper-Changing Steps for Childcare Settings Body Hygiene Dental Hygiene Water Fluoridation Facial Cleanliness Fish Pedicures and ... spread of hygiene-related diseases . Topics for Body Hygiene Facial Cleanliness Dental Hygiene Water Fluoridation Fish Pedicures and Fish Spas ...

  20. Body Image

    Science.gov (United States)

    ... Help your child have a healthy body image Cosmetic surgery Breast surgery Botox Liposuction Varicose or spider veins Body dysmorphic disorder (BDD) Eating disorders Anorexia nervosa Binge eating ... nervosa Cosmetics and your health Depression during and after pregnancy ...

  1. Body Basics

    Science.gov (United States)

    ... about how the body works, what basic human anatomy is, and what happens when parts of the body don't function properly. Blood Bones, Muscles, and Joints Brain and Nervous System Digestive System Endocrine System Eyes Female Reproductive System ...

  2. Body embellishment

    OpenAIRE

    Zellweger, Christoph

    2015-01-01

    The exhibition Body Embellishment explores the most innovative artistic expression in the 21st-century international arenas of body extension, augmentation, and modification, focusing on jewelry, tattoos, nail arts, and fashion. The areas of focus are jewelry, tattoos, nail arts, and fashion. Avant-garde jewelry consciously engages the body by intersecting and expanding the planes of the human form. Tattoos are at once on and in the body. Nail art, from manicures to pedicures, has humble ...

  3. Body Clock

    Institute of Scientific and Technical Information of China (English)

    刘洪毓

    2000-01-01

    Body clocks” are biological methods of controling body activities.Every living thing has one. In humans, a body clock controls normal periods of sleeping and waking. It controls the time swhen you are most likely to feel pain.Eating, sleeping and exercising at about the same time each day will help keep body activities normal. But changes in your life, a new job, for example, destroy the balance and thus cause health problems.

  4. Aspiração de corpo estranho por menores de 15 anos: experiência de um centro de referência do Brasil Foreign body aspiration in children and adolescents: experience of a Brazilian referral center

    Directory of Open Access Journals (Sweden)

    Sílvia Teresa Evangelista Vidotto de Sousa

    2009-07-01

    Full Text Available OBJETIVO: Descrever as características clínicas, radiológicas e endoscópicas da aspiração de corpo estranho por menores de 15 anos em um centro de referência em São Luís, MA. MÉTODOS:Estudo descritivo realizado a partir de dados de prontuários dos pacientes atendidos no Hospital Universitário Materno Infantil devido à aspiração de corpo estranho entre 1995 e 2005. Avaliamos 72 casos confirmados de aspiração de corpo estranho em relação à procedência, variáveis biológicas, clínico-radiológicas e endoscópicas. Para verificar se as frequências observadas das variáveis em estudo foram estatisticamente significantes, utilizamos o teste do qui-quadrado. RESULTADOS: A maioria do pacientes era procedente das cidades do interior (55,6%. As maiores frequências das diferentes variáveis estudadas foram as seguintes: faixa etária de 0-3 anos (81,9%; sexo masculino (63,9%; tempo de evolução > 24 h (66,7%; hipotransparência na radiografia de tórax (57,7%; localização do corpo estranho no pulmão direito (41,2% ou na laringe (20.5%; natureza orgânica do corpo estranho (83,3%; complicação como processo inflamatório localizado (59,4%; edema de glote como complicação do exame endoscópico (47,6%; e sementes (46,6%, espinha de peixe (28,3% e plásticos (25,5% como tipos mais frequentes de corpos estranhos aspirados. Não houve óbitos. CONCLUSÕES: Cuidados preventivos devem priorizar crianças menores de três anos de idade, do sexo masculino, provenientes de cidades do interior. O acesso dessas crianças às substâncias com risco potencial para aspiração, incluindo os alimentos, deve ser evitado. Exames radiológicos simples e de fácil acesso à população são subutilizados, o que compromete a qualidade do primeiro atendimento.OBJECTIVE: To describe the clinical, radiological and endoscopic characteristics of foreign body aspiration among individuals under the age of 15 treated at a referral center in the city of

  5. Construction of a 3D meso-structure and analysis of mechanical properties for deposit body medium

    Institute of Scientific and Technical Information of China (English)

    石崇; 陈凯华; 徐卫亚; 张海龙; 王海礼; 王盛年

    2015-01-01

    For deposit body medium, the internal structural properties may be the controlling factors for the strength of the material and the mechanical response. Based on the results of soil-rock meso-statistics using digital imaging, a simulated annealing algorithm is adopted to expand the meso-structural features of deposit bodies in 3D. The construction of the 3D meso-structure of a deposit body is achieved, and then the particle flow analysis program PFC3D is used to simulate the mechanical properties of the deposit body. It is shown that with a combination of the simulated annealing algorithm and the statistical feature functions, the randomness and heterogeneity of the rock distribution in the 3D inner structure of deposit body medium can be realized, and the reconstructed structural features of the deposit medium can match the features of the digital images well. The spatial utilizations and the compacting effects of the body-centered cubic, hexagonal close and face-centered packing models are high, so these structures can be applied in the simulations of the deposit structures. However, the shear features of the deposit medium vary depending on the different model constructive modes. Rocks, which are the backbone of the deposit, are the factors that determine the shear strength and deformation modulus of the deposit body. The modeling method proposed is useful for the construction of 3D meso-scope models from 2D meso-scope statistics and can be used for studying the mechanical properties of mixed media, such as deposit bodies.

  6. Job center

    Science.gov (United States)

    To better meet the needs of AGU members, a program has been started to increase the effectiveness of the Job Center activity at the Spring and Fall Meetings. As a result, participation in the Job Center at the 1988 AGU Spring Meeting in Baltimore increased substantially compared to previous Spring Meetings. The number of employers, applicants, and interviews scheduled more than doubled compared to the 1987 Spring Job Center.In order to make the meeting Job Centers even better, a survey is being conducted of employers and applicants who participated in the 1988 Spring Job Center. Evaluation of this survey will be useful in continuing increased participation in and the effectiveness of the Job Center at the 1988 Fall Meeting. Past participants and those interested in the future of the Job Center are encouraged to forward comments and suggestions to AGU, Member Programs Division, 2000 Florida Ave., N.W., Washington, DC 20009.

  7. The boundary of the moduli space of stable cubic fivefolds

    OpenAIRE

    Shibata, Yasutaka

    2014-01-01

    By GIT theory due to Mumford, the moduli space of stable cubic fivefolds is compactified by adding non stable semi-stable (i.e. strictly semi-stable) locus. In this paper, we prove that this locus consists of 19 components. Moreover, we give a description of equation and singularity of cubic fivefold corresponding to the generic point in each component.

  8. Method for determination of cubic monocrystals orientation

    International Nuclear Information System (INIS)

    A procedure has been developed for determining cubic monocrystal orientation indirectly in the process of their growing by electrolysis in melted salts. The procedure resides in determination of the angles between two edges of the crystal with known indices [hkl] going from one vertex normal to the substrate plane whose indices must be determined. Determination of the angles consists in measuring the projections of the edges on the substrate plane and the norma to this plane by optical method with the aid of a microscope. The microscope is fitted with a special device for such measurements. The procedure allows for fast and accurate (+-5%) determination of the necessary parameters of the crystal. The proposed method can be used in the case of crystal growth both in aqueous and gaseous media. This method has been used for measuring the vertex coordinates of a sodium-tungsten bronze monocrystal growing in the melt Na2WO4-20%WO3

  9. Black holes in a cubic Galileon universe

    Science.gov (United States)

    Babichev, E.; Charmousis, C.; Lehébel, A.; Moskalets, T.

    2016-09-01

    We find and study the properties of black hole solutions for a subclass of Horndeski theory including the cubic Galileon term. The theory under study has shift symmetry but not reflection symmetry for the scalar field. The Galileon is assumed to have linear time dependence characterized by a velocity parameter. We give analytic 3-dimensional solutions that are akin to the BTZ solutions but with a non-trivial scalar field that modifies the effective cosmological constant. We then study the 4-dimensional asymptotically flat and de Sitter solutions. The latter present three different branches according to their effective cosmological constant. For two of these branches, we find families of black hole solutions, parametrized by the velocity of the scalar field. These spherically symmetric solutions, obtained numerically, are different from GR solutions close to the black hole event horizon, while they have the same de-Sitter asymptotic behavior. The velocity parameter represents black hole primary hair.

  10. Black holes in a cubic Galileon universe

    CERN Document Server

    Babichev, Eugeny; Lehébel, Antoine; Moskalets, Tetiana

    2016-01-01

    We find and study the properties of black hole solutions for a subclass of Horndeski theory including the cubic Galileon term. The theory under study has shift symmetry but not reflection symmetry for the scalar field. The Galileon is assumed to have linear time dependence characterized by a velocity parameter. We give analytic 3-dimensional solutions that are akin to the BTZ solutions but with a non-trivial scalar field that modifies the effective cosmological constant. We then study the 4-dimensional asymptotically flat and de Sitter solutions. The latter present three different branches according to their effective cosmological constant. For two of these branches, we find families of black hole solutions, parametrized by the velocity of the scalar field. These spherically symmetric solutions, obtained numerically, are different from GR solutions close to the black hole event horizon, while they have the same de-Sitter asymptotic behavior. The velocity parameter represents black hole primary hair.

  11. Niobium-titanium superconductors produced by powder metallurgy having artificial flux pinning centers

    Science.gov (United States)

    Jablonski, Paul D.; Larbalestier, David C.

    1993-01-01

    Superconductors formed by powder metallurgy have a matrix of niobium-titanium alloy with discrete pinning centers distributed therein which are formed of a compatible metal. The artificial pinning centers in the Nb-Ti matrix are reduced in size by processing steps to sizes on the order of the coherence length, typically in the range of 1 to 10 nm. To produce the superconductor, powders of body centered cubic Nb-Ti alloy and the second phase flux pinning material, such as Nb, are mixed in the desired percentages. The mixture is then isostatically pressed, sintered at a selected temperature and selected time to produce a cohesive structure having desired characteristics without undue chemical reaction, the sintered billet is reduced in size by deformation, such as by swaging, the swaged sample receives heat treatment and recrystallization and additional swaging, if necessary, and is then sheathed in a normal conducting sheath, and the sheathed material is drawn into a wire. The resulting superconducting wire has second phase flux pinning centers distributed therein which provide enhanced J.sub.ct due to the flux pinning effects.

  12. Functional Centering

    CERN Document Server

    Hahn, M

    1996-01-01

    Based on empirical evidence from a free word order language (German) we propose a fundamental revision of the principles guiding the ordering of discourse entities in the forward-looking centers within the centering model. We claim that grammatical role criteria should be replaced by indicators of the functional information structure of the utterances, i.e., the distinction between context-bound and unbound discourse elements. This claim is backed up by an empirical evaluation of functional centering.

  13. Methane hydrate dissociation using inverted five-spot water flooding method in cubic hydrate simulator

    International Nuclear Information System (INIS)

    The combination forms of the hydrate dissociation methods in different well systems are divided into 6 main patterns. Dissociation processes of methane hydrate in porous media using the inverted five-spot water flooding method (Pattern 4) are investigated by the experimental observation and numerical simulation. In situ methane hydrate is synthesized in the Cubic Hydrate Simulator (CHS), a 5.832-L cubic reactor. A center vertical well is used as the hot water injection well, while the four vertical wells at the corner are the gas and water production wells. The gas production begins simultaneously with the hot water injection, while after approximately 20 min of compression, the water begins to be produced. One of the common characteristics of the inverted five-spot water flooding method is that both the gas and water production rates decrease with the reduction of the hydrate dissociation rate. The evaluation of the energy efficiency ratio might indicate the inverted five-spot water flooding as a promising gas producing method from the hydrate reservoir. - Highlights: • A three-dimensional 5.8-L cubic pressure vessel is developed. • Gas production of hydrate using inverted five-spot flooding method is studied. • Water/gas production rate and energy efficiency ratio are evaluated. • Temperature distributions of numerical simulation and experiment agree well. • Hydrate dissociation process is a moving boundary problem in this study

  14. Cubic Polynomial Maps with Periodic Critical Orbit, Part II: Escape Regions

    CERN Document Server

    Bonifant, Araceli; Milnor, John

    2009-01-01

    The parameter space $\\mathcal{S}_p$ for monic centered cubic polynomial maps with a marked critical point of period $p$ is a smooth affine algebraic curve whose genus increases rapidly with $p$. Each $\\mathcal{S}_p$ consists of a compact connectedness locus together with finitely many escape regions, each of which is biholomorphic to a punctured disk and is characterized by an essentially unique Puiseux series. This note will describe the topology of $\\mathcal{S}_p$, and of its smooth compactification, in terms of these escape regions. It concludes with a discussion of the real sub-locus of $\\mathcal{S}_p$.

  15. Distribution center

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Distribution center is a logistics link fulfill physical distribution as its main functionGenerally speaking, it's a large and hiahly automated center destined to receive goods from various plants and suppliers,take orders,fill them efficiently,and deliver goods to customers as quickly as possible.

  16. Body punk

    DEFF Research Database (Denmark)

    Mogensen, Kevin

    BODYPUNK - A Treatise on male body builders and the meaning of the body in the shadow of an Anti Doping Campaign Based on a qualitative study, the thesis investigates the visual representation of the male bodybuilder found in the national anti doping campaign: ‗ "The hunt has begun" along with an...... analysis of the embodied meaning of men‘s bodybuilding....

  17. Body Weight and Body Image

    OpenAIRE

    McFarlane Traci; Olmsted Marion P

    2004-01-01

    Abstract Health Issue Body weight is of physical and psychological importance to Canadian women; it is associated with health status, physical activity, body image, and self-esteem. Although the problems associated with overweight and obesity are indeed serious, there are also problems connected to being underweight. Weight prejudice and the dieting industry intensify body image concerns for Canadian women and can have a major negative impact on self-esteem. Key Findings Women have lower BMIs...

  18. Quasi-two-dimensional Bose-Einstein condensates with spatially modulated cubic-quintic nonlinearities

    Science.gov (United States)

    Dai, Chao-Qing; Wang, Deng-Shan; Wang, Liang-Liang; Zhang, Jie-Fang; Liu, W. M.

    2011-09-01

    We investigate exact nonlinear matter wave functions with odd and even parities in the framework of quasi-two-dimensional Bose-Einstein condensates (BECs) with spatially modulated cubic-quintic nonlinearities and harmonic potential. The existence condition for these exact solutions requires that the minimum energy eigenvalue of the corresponding linear Schrödinger equation with harmonic potential is the cutoff value of the chemical potential λ. The competition between two-body and three-body interactions influences the energy of the localized state. For attractive two-body and three-body interactions, the larger the matter wave order number n, the larger the energy of the corresponding localized state. A linear stability analysis and direct simulations with initial white noise demonstrate that, for the same state (fixed n), increasing the number of atoms can add stability. A quasi-stable ground-state matter wave is also found for repulsive two-body and three-body interactions. We also discuss the experimental realization of these results in future experiments. These results are of particular significance to matter wave management in higher-dimensional BECs.

  19. Topological Oxide Insulator in Cubic Perovskite Structure

    Science.gov (United States)

    Jin, Hosub; Rhim, Sonny H.; Im, Jino; Freeman, Arthur J.

    2013-04-01

    The emergence of topologically protected conducting states with the chiral spin texture is the most prominent feature at the surface of topological insulators. On the application side, large band gap and high resistivity to distinguish surface from bulk degrees of freedom should be guaranteed for the full usage of the surface states. Here, we suggest that the oxide cubic perovskite YBiO3, more than just an oxide, defines itself as a new three-dimensional topological insulator exhibiting both a large bulk band gap and a high resistivity. Based on first-principles calculations varying the spin-orbit coupling strength, the non-trivial band topology of YBiO3 is investigated, where the spin-orbit coupling of the Bi 6p orbital plays a crucial role. Taking the exquisite synthesis techniques in oxide electronics into account, YBiO3 can also be used to provide various interface configurations hosting exotic topological phenomena combined with other quantum phases.

  20. Influence of a hydrostatic pressure on the diffusion in metals having a cubic structure; Contribution a l'etude de l'influence de la pression hydrostatique sur la diffusion dans les metaux cubiques

    Energy Technology Data Exchange (ETDEWEB)

    Beyeler, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    In view of obtaining informations on the structure of vacancies. We have determined, by diffusion experiments under high pressure, the activation volumes for self diffusion in different face centered cubic metals: silver, gold, copper, aluminium and in body centered cubic uranium (gamma phase). Activation volumes for noble metals diffusion in aluminium have also been investigated. The experimental results on gold, silver and copper are in good agreement with most of the theoretical models. The estimated activation volume for gamma uranium seems to indicate a vacancy mechanism.The results on aluminium for both self and impurity diffusion agree quite well with Friedel's theoretical predictions. [French] Pour preciser la structure des lacunes, on a, par des etudes de diffusion sous haute pression determine les volumes d'activation correspondant a l'autodiffusion dans des metaux de structure cubique face centree: argent, or, cuivre et aluminium et dans un metal de structure cubique centree: l'uranium gamma. On a egalement determine les volumes d'activation pour l'heterodiffusion des metaux nobles dans l'aluminium. Les resultats obtenus pour l'or, l'argent et le cuivre sont en accord avec la plupart des modeles theoriques classiques. Le volume d'activation d'autodiffusion evalue pour l'uranium gamma est compatible avec une diffusion par lacune. Les resultats concernant l'aluminium et l'heterediffusion des metaux nobles dans l'aluminium verifient assez bien les previsions theoriques de Friedel. (auteur)

  1. Senior Centers

    Medline Plus

    Full Text Available ... variety of social and recreational activities. [Karen Albers] We provide a wide variety of activities -- physical, health, ... senior centers also offer exercise programs. [Karen Albers] We offer aerobics, tai chi, tap dancing, ballroom dancing, ...

  2. Senior Centers

    Medline Plus

    Full Text Available ... transportation, and meals programs are long-term care services available in the community which make it easier ... about senior centers and other long-term care services available in your community, contact the Eldercare Locator ...

  3. Senior Centers

    Medline Plus

    Full Text Available ... Karen Albers] We provide a wide variety of activities -- physical, health, mental health programs with Senior Plus, cognitive ... of games. [Narrator] Many senior centers also offer exercise programs. [Karen Albers] We offer aerobics, tai chi, ...

  4. Senior Centers

    Medline Plus

    Full Text Available [Narrator] Living independently at home is something many older adults would like to do as long as they can. Senior centers, adult day care, transportation, and meals programs are ...

  5. Senior Centers

    Medline Plus

    Full Text Available ... Living independently at home is something many older adults would like to do as long as they can. Senior centers, adult day care, transportation, and meals programs are long- ...

  6. Senior Centers

    Medline Plus

    Full Text Available ... of games. [Narrator] Many senior centers also offer exercise programs. [Karen Albers] We offer aerobics, tai chi, ... chi, tap dancing, ballroom dancing, square dancing, chair exercise, arthritis classes, yoga, and lots of dancing. [Narrator] ...

  7. Senior Centers

    Medline Plus

    Full Text Available ... something many older adults would like to do as long as they can. Senior centers, adult day care, transportation, ... adults who live independently can go to find a variety of social and recreational activities. [Karen Albers] ...

  8. Body lice

    Science.gov (United States)

    Lice - body; Pediculosis corporis; Vagabond disease ... Diaz JH. Lice (pediculosis). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases . 8th ...

  9. Bog bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2015-01-01

    the bog bodies have been studied using medical and natural scientific methods, and recently many bog bodies have been re-examined using especially modern, medical imaging techniques. Because of the preservation of soft tissue, especially the skin, it has been possible to determine lesions and trauma......In northern Europe during the Iron Age, many corpses were deposited in bogs. The cold, wet and anaerobic environment leads in many cases to the preservation of soft tissues, so that the bodies, when found and excavated several thousand years later, are remarkably intact. Since the 19th century....... Conversely, the preservation of bones is less good, as the mineral component has been leached out by the acidic bog. Together with water-logging of collagenous tissue, this means that if the bog body is simply left to dry out when found, as was the case pre-19th century, the bones may literally warp...

  10. The Coulombic Lattice Potential of Ionic Compounds: The Cubic Perovskites.

    Science.gov (United States)

    Francisco, E.; And Others

    1988-01-01

    Presents coulombic models representing the particles of a system by point charges interacting through Coulomb's law to explain coulombic lattice potential. Uses rubidium manganese trifluoride as an example of cubic perovskite structure. Discusses the effects on cluster properties. (CW)

  11. Spinning solitons in cubic-quintic nonlinear media

    Indian Academy of Sciences (India)

    Lucian-Cornel Crasovan; Boris A Malomed; Dumitru Mihalache

    2001-11-01

    We review recent theoretical results concerning the existence, stability and unique features of families of bright vortex solitons (doughnuts, or ‘spinning’ solitons) in both conservative and dissipative cubic-quintic nonlinear media.

  12. Alpha decay by cubic plus Yukawa plus exponential model

    International Nuclear Information System (INIS)

    The half life of alpha decay in some nuclei by using cubic plus Yukawa plus exponential model (CYCM) of Shanmugam and Kamalaharan is calculated in this project and compared with the available experimental values

  13. Display blocks: cubic displays for multi-perspective visualization

    OpenAIRE

    Pla i Conesa, Pol; Maes, Patricia

    2012-01-01

    We propose the design, implementation and evaluation of a set of tangible cubic displays. This novel approach to display technology consists of arranging six organic light emitting diode screens in a cubic form factor. We explore the possibilities that this type of display holds for data visualization, manipulation and exploration. We are especially interested in exploring how the physicality of the screen can be perceived as a cue to better interpret its contents. To this end, we propose a s...

  14. Interaction of dispersed cubic phases with blood components

    DEFF Research Database (Denmark)

    Bode, J C; Kuntsche, Judith; Funari, S S; Bunjes, H

    2013-01-01

    The interaction of aqueous nanoparticle dispersions, e.g. based on monoolein/poloxamer 407, with blood components is an important topic concerning especially the parenteral way of administration. Therefore, the influence of human and porcine plasma on dispersed cubic phases was investigated. Part...... activity of cubic phases based on monoolein and poloxamer 188, on soy phosphatidylcholine, glycerol dioleate and polysorbate 80 or the parenteral fat emulsion Lipofundin MCT 20%....

  15. Cubic boron nitride- a new material for ultracold neutron application

    International Nuclear Information System (INIS)

    For the first time, the Fermi potential of cubic boron nitride (cBN) was measured at the ultra cold neutron source at the TRIGA reactor, Mainz using the time of flight method (TOF). The investigated samples have a Fermi potential of about 300 neV. Because of its good dielectric characteristics, cubic boron nitride could be used as suitable coating for insulator in storage chambers of future EDM projects. This talk presents recent results and an outlook on further investigations.

  16. Optical characterisation of cubic silicon carbide

    International Nuclear Information System (INIS)

    The varied properties of Silicon Carbide (SiC) are helping to launch the material into many new applications, particularly in the field of novel semiconductor devices. In this work, the cubic form of SiC is of interest as a basis for developing integrated optical components. Here, the formation of a suitable SiO2 buried cladding layer has been achieved by high dose oxygen ion implantation. This layer is necessary for the optical confinement of propagating light, and hence optical waveguide fabrication. Results have shown that optical propagation losses of the order of 20 dB/cm are obtainable. Much of this loss can be attributed to mode leakage and volume scattering. Mode leakage is a function of the effective oxide thickness, and volume scattering related to the surface layer damage. These parameters have been shown to be controllable and so suggests that further reduction in the waveguide loss is feasible. Analysis of the layer growth mechanism by RBS, XTEM and XPS proves that SiO2 is formed, and that the extent, of formation depends on implant dose and temperature. The excess carbon generated is believed to exit the oxide layer by a number of varying mechanisms. The result of this appears to be a number of stable Si-C-O intermediaries that, form regions to either depth extreme of the SiO2 layer. Early furnace tests suggest a need to anneal at, temperatures approaching the melting point of the silicon substrate, and that the quality of the virgin material is crucial in controlling the resulting oxide growth. (author)

  17. Human Body Image Edge Detection Based on Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    李勇; 付小莉

    2003-01-01

    Human dresses are different in thousands way.Human body image signals have big noise, a poor light and shade contrast and a narrow range of gray gradation distribution. The application of a traditional grads method or gray method to detect human body image edges can't obtain satisfactory results because of false detections and missed detections. According to tte peculiarity of human body image, dyadic wavelet transform of cubic spline is successfully applied to detect the face and profile edges of human body image and Mallat algorithm is used in the wavelet decomposition in this paper.

  18. Signifying Bodies

    DEFF Research Database (Denmark)

     In our everyday lives we strive to stay healthy and happy, while we live as our selves, engage with each other, and discover an infinite world of possibilities. Health arises and diminishes as human beings draw on a vibrant ecology of actions, interactions and coactions. Intricate processes of...... biosemiosis connect signifying bodies with their natural surroundings, cultural activities and subjective experiences. Health stretches all the way from the ecosocial surroundings, through the skin and into the self-organizing processes of every living cell. Signifying Bodies lays out a new approach to health...... and health care. Eschewing all forms of dualism, the authors emphasise the interdependency of how we act, think, feel and function. They advocate a relational turn in health care, in which bodies live and learn from suffering and care. In this view, health is inseparable from both living beings and...

  19. Body Imaging

    Science.gov (United States)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images.

  20. Body Rainbow

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    Phubu did not know how long hehad walked after leaving Baxoi, buthe did know that he was halfwaybetween home and Lhasa. Feelingthe weight of the sack containingPhumo's body on his back, Fhubuhad calmed down from the grief anddesperation. He had just one wish:to carry Phumo to Lhasa. He knewthat Phumo had gone, and her soulwas no longer in this body. But hewas determined to finish the trip, notonly because he had promised so, butalso that he believed that it would beredemption for him.

  1. Sacralising Bodies

    DEFF Research Database (Denmark)

    Kaur, Ravinder

    2010-01-01

    sacralisation is realised through co-production within a social setting when the object of sacralisation is recognised as such by others. In contemporary Iran, however, the moment of sacralising bodies by the state is also the moment of its own subversion as the political-theological field of martyrdom is......-sacrifice became central to the mass mobilisation against the monarchy. Once the revolutionary government came into existence, this sacred tradition was regulated to create ‘martyrs’ as a fixed category, in order to consolidate the legacy of the revolution. In this political theatre, the dead body is a site of...

  2. Senior Centers

    Medline Plus

    Full Text Available ... provide a wide variety of activities -- physical, health, mental health programs with Senior Plus, cognitive programs, a wide variety of general activities, billiards, Bingo, lots of games. [Narrator] Many senior centers also offer exercise programs. [Karen Albers] We offer aerobics, tai chi, ...

  3. Hastings Center

    Science.gov (United States)

    ... BLOG We have long had the ability, we humans, to work outside the bounds of evolution. Dairy cattle, maize, and all sorts of dog ... intervention. However, in the past, the scope of human intervention was rather… Read more Share: ... Evolution? Read more HASTINGS NEWS Hastings Center research scholar ...

  4. Senior Centers

    Medline Plus

    Full Text Available ... dancing. [Narrator] These centers can provide entree to new activities and expand a person’s social contacts. [Karen ... meeting all their interests and introducing them to new things; whether it’s an arts and crafts project, ...

  5. Senior Centers

    Medline Plus

    Full Text Available ... transportation, and meals programs are long-term care services available in the community which make it easier for older adults to ... about senior centers and other long-term care services available in your community, contact the Eldercare Locator at 1-800-677- ...

  6. Progress in computerized body tomography

    International Nuclear Information System (INIS)

    Since computerized tomography of the head has become well-established as a most important diagnostic tool in medicine, technical advance and scientific investigation has centered on CT of the remainder of the body. A proliferation of scientific papers covering many aspects of body scanning has occured, but the evidence is only slowly emerging to establish the indications, advantages, and cost effectiveness of computerized tomography below the head. An appraisal of the present status of computerized body tomography from viewpoint of the clinical radiologist is presented. 1977 planning recommendations for the western United States are cited. (orig.) 891 MG/orig. 892 MB

  7. Centered Pyramids

    OpenAIRE

    Brigger, P.; F. Müller; Illgner, K.; Unser, M.

    1999-01-01

    Quadtree-like pyramids have the advantage of resulting in a multiresolution representation where each pyramid node has four unambiguous parents. Such a centered topology guarantees a clearly defined up-projection of labels. This concept has been successfully and extensively used in applications of contour detection, object recognition and segmentation. Unfortunately, the quadtree-like type of pyramid has poor approximation powers because of the employed piecewise-constant image model. This pa...

  8. IRASM Center

    International Nuclear Information System (INIS)

    IRASM is a national center for radiation processing developed around an industrial Co60 gamma irradiator. Being a department in an R and D national institute, IRASM Center is dealing with radiation treatment, pre/post microbiological control, validation of irradiation sterilization, detection of irradiated foodstuffs. Training is available for operators of new irradiation facilities focused on radiation technologies, dosimetry, sterilization, food treatment, conservation by irradiation of cultural heritage, quality assurance. Expertise on proper choosing the plastics for packaging versus dose is offered to the potential clients. IRASM Center is also involved in interdisciplinary applied research like chitosan treatment, sterile male technique or implementation of irradiation step in production of pharmaceuticals. All important activities: irradiation treatment, dosimetry, microbiology, detection of irradiated food, radioprotection, nuclear safety, physical protection. are performed in accordance with the proper standards in the frame of a certified quality management system. In this way Co60 industrial sources, a byproduct of certain nuclear power plants like Candu type, appear to be the key of a large technical and R and D domain. (authors)

  9. Growth and characterization of {beta}-In N films on Mg O: the key role of a {beta}-Ga N buffer layer in growing cubic In N

    Energy Technology Data Exchange (ETDEWEB)

    Navarro C, H.; Perez C, M.; Rodriguez, A. G.; Lopez L, E.; Vidal, M. A. [Universidad Autonoma de San Luis Potosi, Coordinacion para la Innovacion y la Aplicacion de la Ciencia y la Tecnologia, Alvaro Obregon 64, 78000 San Luis Potosi (Mexico)

    2012-07-01

    Cubic In N samples were grown on Mg O (001) substrates by gas source molecular beam epitaxy. In general, we find that In N directly deposited onto the Mg O substrate results in polycrystalline or columnar films of hexagonal symmetry. We find that adequate conditions to grow the cubic phase of this compound require the growth of an initial cubic Ga N buffer interlayer ({beta}-t Ga N) on the Mg O surface. Subsequently, the growth conditions were optimized to obtain good photoluminescence (Pl) emission. The resultant In N growth is mostly cubic, with very small hexagonal inclusions, as confirmed by X-ray diffraction and scanning electron microscopy studies. Good crystalline quality requires that the samples to be grown under rich Indium metal flux. The cubic {beta}-t In N/Ga N/Mg O samples exhibit a high signal to noise ratio for Pl at low temperatures (20 K). The Pl is centered at O.75 eV and persist at room temperature. (Author)

  10. Spinor bose gases in cubic optical lattice

    International Nuclear Information System (INIS)

    In recent years the quantum simulation of condensed-matter physics problems has resulted from exciting experimental progress in the realm of ultracold atoms and molecules in optical lattices. In this thesis we analyze theoretically a spinor Bose gas loaded into a three-dimensional cubic optical lattice. In order to account for different superfluid phases of spin-1 bosons with a linear Zeeman effect, we work out a Ginzburg-Landau theory for the underlying spin-1 Bose-Hubbard model. To this end we add artificial symmetry-breaking currents to the spin-1 Bose-Hubbard Hamiltonian in order to break the global U (1) symmetry. With this we determine a diagrammatic expansion of the grand-canonical free energy up to fourth order in the symmetry-breaking currents and up to the leading non-trivial order in the hopping strength which is of first order. As a cross-check we demonstrate that the resulting grand-canonical free energy allows to recover the mean-field theory. Applying a Legendre transformation to the grand-canonical free energy, where the symmetry-breaking currents are transformed to order parameters, we obtain the effective Ginzburg-Landau action. With this we calculate in detail at zero temperature the Mott insulator-superfluid quantum phase boundary as well as condensate and particle number density in the superfluid phase. We find that both mean-field and Ginzburg-Landau theory yield the same quantum phase transition between the Mott insulator and superfluid phases, but the range of validity of the mean-field theory turns out to be smaller than that of the Ginzburg-Landau theory. Due to this finding we expect that the Ginzburg-Landau theory gives better results for the superfluid phase and, thus, we restrict ourselves to extremize only the effective Ginzburg-Landau action with respect to the order parameters. Without external magnetic field the superfluid phase is a polar (ferromagnetic) state for anti-ferromagnetic (ferromagnetic) interactions, i.e. only the

  11. Spinor bose gases in cubic optical lattice

    Energy Technology Data Exchange (ETDEWEB)

    Mobarak, Mohamed Saidan Sayed Mohamed

    2014-01-27

    In recent years the quantum simulation of condensed-matter physics problems has resulted from exciting experimental progress in the realm of ultracold atoms and molecules in optical lattices. In this thesis we analyze theoretically a spinor Bose gas loaded into a three-dimensional cubic optical lattice. In order to account for different superfluid phases of spin-1 bosons with a linear Zeeman effect, we work out a Ginzburg-Landau theory for the underlying spin-1 Bose-Hubbard model. To this end we add artificial symmetry-breaking currents to the spin-1 Bose-Hubbard Hamiltonian in order to break the global U (1) symmetry. With this we determine a diagrammatic expansion of the grand-canonical free energy up to fourth order in the symmetry-breaking currents and up to the leading non-trivial order in the hopping strength which is of first order. As a cross-check we demonstrate that the resulting grand-canonical free energy allows to recover the mean-field theory. Applying a Legendre transformation to the grand-canonical free energy, where the symmetry-breaking currents are transformed to order parameters, we obtain the effective Ginzburg-Landau action. With this we calculate in detail at zero temperature the Mott insulator-superfluid quantum phase boundary as well as condensate and particle number density in the superfluid phase. We find that both mean-field and Ginzburg-Landau theory yield the same quantum phase transition between the Mott insulator and superfluid phases, but the range of validity of the mean-field theory turns out to be smaller than that of the Ginzburg-Landau theory. Due to this finding we expect that the Ginzburg-Landau theory gives better results for the superfluid phase and, thus, we restrict ourselves to extremize only the effective Ginzburg-Landau action with respect to the order parameters. Without external magnetic field the superfluid phase is a polar (ferromagnetic) state for anti-ferromagnetic (ferromagnetic) interactions, i.e. only the

  12. Philippine Heart Center: the specialist

    International Nuclear Information System (INIS)

    The Philippine Heart Center introduced the use of computer technology to further improve management services to their patients. In the Nuclear Medicine Department, the gamma camera system interfaced with computers and the cardiac catheterization laboratory's X-ray angio system was used in diagnostic procedures not only the heart but also on the different vital organs of the body. 3 photos

  13. A new hypercube variant: Fractal Cubic Network Graph

    Directory of Open Access Journals (Sweden)

    Ali Karci

    2015-03-01

    Full Text Available Hypercube is a popular and more attractive interconnection networks. The attractive properties of hypercube caused the derivation of more variants of hypercube. In this paper, we have proposed two variants of hypercube which was called as “Fractal Cubic Network Graphs”, and we have investigated the Hamiltonian-like properties of Fractal Cubic Network Graphs FCNGr(n. Firstly, Fractal Cubic Network Graphs FCNGr(n are defined by a fractal structure. Further, we show the construction and characteristics analyses of FCNGr(n where r=1 or r=2. Therefore, FCNGr(n is a Hamiltonian graph which is obtained by using Gray Code for r=2 and FCNG1(n is not a Hamiltonian Graph. Furthermore, we have obtained a recursive algorithm which is used to label the nodes of FCNG2(n. Finally, we get routing algorithms on FCNG2(n by utilizing routing algorithms on the hypercubes.

  14. Analysis of cubic permutation polynomials for turbo codes

    CERN Document Server

    Trifina, Lucian

    2011-01-01

    Quadratic permutation polynomials (QPPs) have been widely studied and used as interleavers in turbo codes. However, less attention has been given to cubic permutation polynomials (CPPs). This paper proves a theorem which states sufficient and necessary conditions for a cubic permutation polynomial to be a null permutation polynomial. The result is used to reduce the search complexity of CPP interleavers for short lengths (multiples of 8, between 40 and 256), by improving the distance spectrum over the set of polynomials with the largest spreading factor. The comparison with QPP interleavers is made in terms of search complexity and upper bounds of the bit error rate (BER) and frame error rate (FER) for AWGN channel. Cubic permutation polynomials leading to better performance than quadratic permutation polynomials are found for some lengths.

  15. Low-temperature thermostatics of face-centered-cubic metallic hydrogen

    Science.gov (United States)

    Caron, L. G.

    1974-01-01

    The thermostatic properties of a high-symmetry phase of metallic hydrogen with atomic sphere radius between 0.1 and 1.5 bohr are studied, with special emphasis accorded to electronic screening and quantum proton motion. The electron-proton and proton-proton interactions receive a perturbation treatment based on the Singwi dielectric function, while the proton motion is handled by self-consistent harmonic approximation. Quantum behavior is found to be less pronounced than expected, and nuclear magnetism is absent. The phonon spectrum is, however, affected by screening and large proton motion. The zero-point vibrational energy and the superconducting critical temperature are below previous estimates. The crystalline-defect formation energies are a few times the Debye energy, which implies that defects contribute significantly to melting at the lower particle densities.

  16. Thermal plasma processed ferro-magnetically ordered face-centered cubic iron at room temperature

    International Nuclear Information System (INIS)

    Here, we report tailor made phase of iron nanoparticles using homogeneous gas phase condensation process via thermal plasma route. It was observed that crystal lattice of nano-crystalline iron changes as a function of operating parameters of the plasma reactor. In the present investigation iron nanoparticles have been synthesized in presence of argon at operating pressures of 125–1000 Torr and fixed plasma input DC power of 6 kW. It was possible to obtain pure fcc, pure bcc as well as the mixed phases for iron nanoparticles in powder form as a function of operating pressure. The as synthesized product was characterized for understanding the structural and magnetic properties by using X-ray diffraction, vibrating sample magnetometer, and Mössbauer spectroscopy. The data reveal that fcc phase is ferromagnetically ordered with high spin state, which is unusual whereas bcc phase is found to be ferromagnetic as usual. Finally, the structural and magnetic properties are co-related.

  17. Multiple jumps and vacancy diffusion in a face-centered-cubic metal

    International Nuclear Information System (INIS)

    The diffusion of monovacancies in gold has been studied by computer simulation. Multiple jumps have been found to play a central role in the atomic dynamics at high temperature, and have been shown to be responsible for an upward curvature in the Arrhenius plot of the diffusion coefficient. Appropriate saddle-points on the potential energy surface have been found, supporting the interpretation of vacancy multiple jumps as distinct migration mechanisms

  18. Study of point defects and matter transport in cubic face centered concentrated alloys

    International Nuclear Information System (INIS)

    It is shown that the second moment approximation to the tight binding method allows a functional to be set up which describes transition metals, noble metals and their alloys. It is assumed that the local electronic density of states is rectangular and that the width varies from site to site. It is then shown how the Monte Carlo method can be used to study order in solid solution with a large difference in size between components: atoms of different nature are exchanged and their neighbours are simultaneously displaced in accordance with the microscopic theory of elasticity. The phase diagram of the simulated alloys is then constructed. Experimental results are qualitatively well reproduced but transition temperatures are difficult to evaluate accurately because of a bad estimation of the vibration entropy. A local tendency towards ordering due to chemical effects is shown at the defect proximity. 40 figs., 100 refs

  19. A broken-bond model for grain boundaries in face-centered cubic metals

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, D. (Materials Science Division, Argonne National Laboratory, Argonne, IL (USA))

    1990-10-01

    The interrelation between the number of nearest-neighbor atomic bonds broken upon formation of a grain boundary in an fcc metal and the related zero-temperature boundary energy is investigated by atomistic simulation. Using both a Lennard--Jones and an embedded-atom-method potential, the structures and energies of symmetrical and asymmetrical tilt and twist boundaries are determined. As in free surfaces, a practically linear relationship between the nearest-neighbor miscoordination per unit area of the grain boundary and the related interface energy is obtained. The so-called random-boundary model, in which the interactions across the interface are assumed to be entirely randomized, is shown to provide a basis for understanding the role of broken bonds in both high-angle grain boundaries and free surfaces, thus naturally permitting the analysis of ideal cleavage-fracture energies. A detailed study of low-angle boundaries shows that only the dislocation cores---but not their strain fields---give rise to broken bonds. The complementarity between the dislocation model of Read and Shockley for low-angle boundaries and a broken-bond model for high-angle boundaries is thus elucidated.

  20. Thermal plasma processed ferro-magnetically ordered face-centered cubic iron at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Raut, Suyog A.; Kanhe, Nilesh S.; Bhoraskar, S. V.; Mathe, V. L., E-mail: vlmathe@physics.unipune.ac.in [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Das, A. K. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2014-10-28

    Here, we report tailor made phase of iron nanoparticles using homogeneous gas phase condensation process via thermal plasma route. It was observed that crystal lattice of nano-crystalline iron changes as a function of operating parameters of the plasma reactor. In the present investigation iron nanoparticles have been synthesized in presence of argon at operating pressures of 125–1000 Torr and fixed plasma input DC power of 6 kW. It was possible to obtain pure fcc, pure bcc as well as the mixed phases for iron nanoparticles in powder form as a function of operating pressure. The as synthesized product was characterized for understanding the structural and magnetic properties by using X-ray diffraction, vibrating sample magnetometer, and Mössbauer spectroscopy. The data reveal that fcc phase is ferromagnetically ordered with high spin state, which is unusual whereas bcc phase is found to be ferromagnetic as usual. Finally, the structural and magnetic properties are co-related.

  1. Structural stability and energetics of grain boundary triple junctions in face centered cubic materials

    Science.gov (United States)

    Adlakha, I.; Solanki, K. N.

    2015-03-01

    We present a systematic study to elucidate the role of triple junctions (TJs) and their constituent grain boundaries on the structural stability of nanocrystalline materials. Using atomistic simulations along with the nudge elastic band calculations, we explored the atomic structural and thermodynamic properties of TJs in three different fcc materials. We found that the magnitude of excess energy at a TJ was directly related to the atomic density of the metal. Further, the vacancy binding and migration energetics in the vicinity of the TJ were examined as they play a crucial role in the structural stability of NC materials. The resolved line tension which takes into account the stress buildup at the TJ was found to be a good measure in predicting the vacancy binding tendency near the TJ. The activation energy for vacancy migration along the TJ was directly correlated with the measured excess energy. Finally, we show that the resistance for vacancy diffusion increased for TJs with larger excess stored energy and the defect mobility at some TJs is slower than their constituent GBs. Hence, our results have general implications on the diffusional process in NC materials and provide new insight into stabilizing NC materials with tailored TJs.

  2. Hydrogen effects on nanovoid nucleation in face-centered cubic single-crystals

    International Nuclear Information System (INIS)

    Monte Carlo (MC) and molecular dynamics (MD) simulations using embedded atom method (EAM) potentials were performed to study nanovoid nucleation in single-crystal nickel specimens in a hydrogen-precharged and a hydrogen dynamically-charged condition. In the hydrogen-precharged condition, MC simulations were performed to introduce hydrogen atoms in an unstressed specimen. MD simulations were then performed to study nanovoid nucleation and the associated plasticity. In the dynamically-charged condition, a novel coupled MD-MC process was used to introduce hydrogen into the specimen while the specimen was being strained until nanovoid nucleation occurred. The simulation results revealed that hydrogen only reduced the nanovoid nucleation stress in the precharged case slightly but caused a lower strain-hardening and a significant reduction in the nanovoid nucleation stress in the dynamically-charged case

  3. Hydrogen four-level tunnel systems in substitutional body-centred cubic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, F. [CNR, Area di Ricerca di Roma - Tor Vergata, Ist. di Acustica ' ' O. M. Corbino' ' , Roma (Italy); INFM (Italy); Cantelli, R. [INFM (Italy); Univ. di Roma ' ' La Sapienza' ' , Dipt. di Fisica, Roma (Italy)

    2002-10-01

    A brief account is provided of the main results of a study of the tunneling states of H trapped by substitutional (S) impurities in Nb, mainly consisting in anelasticity experiments. The phenomenology is rather complex when the concentration of S atoms is higher than a few parts per thousand, and various and contrasting interpretations are possible. The complication arises from the destruction of the symmetry of the S-H pair by the elastic interactions among the defects. The situation becomes, however, clear for an S content around 0.1%, when the anelastic spectra reveal the relaxation processes due to the now nearly undistorted S-H complexes. In this case H delocalizes over four tetrahedral sites of a face of the cube containing the S atom, giving rise to a four-level tunnel system (FLS). The parameters of tunneling and coupling to phonons and electron excitations are similar to those found for the two-level system of H near an interstitial impurity, but new effects are found, due to the symmetry of the additional eigenstates of a centrosymmetric FLS. (orig.)

  4. Spinel type twins of the new cubic Er6Zn23Ge compound

    International Nuclear Information System (INIS)

    The crystal structure of the new Er6Zn23Ge intermetallic compound was established by X-ray diffraction analysis on a twinned crystal (space group Fm anti 3m, Wyckoff sequence: f2edba, cF120-Zr6Zn23Si, a=12.7726(6) Aa). The crystal is composed of two nearly equal size domains, whose mutual orientation is described by a 180 rotation around the cubic [111] axis, i.e. a spinel-type twinning law, not common for intermetallics. Applying the nanocluster approach, Er6Ge octahedra and centered two-shell Zn45 clusters were found as structural building blocks, filling the crystal space in a NaCl-like arrangement. This description was adopted to interpret the twinning in terms of stacking faults in the fcc cubic close packed arrangement. Moreover, the assembly of the nanocluster units is proposed as a possible mechanism for crystal growth and twin formation, in agreement with the principle of the interface energy minimization. Experimental conditions such as supersaturation and co-formation of other phases are also considered as favorable factors for Er6Zn23Ge twin formation.

  5. Counting perfect matchings of cubic graphs in the geometric dual

    CERN Document Server

    Jiménez, Andrea

    2010-01-01

    Lov\\'asz and Plummer conjectured, in the mid 1970's, that every cubic graph G with no cutedge has an exponential in |V(G)| number of perfect matchings. In this work we show that every cubic planar graph G whose geometric dual graph is a stack triangulation has at least 3 times the golden ratio to |V(G)|/72 distinct perfect matchings. Our work builds on a novel approach relating Lov\\'asz and Plummer's conjecture and the number of so called groundstates of the widely studied Ising model from statistical physics.

  6. Multi-point functions of weighted cubic maps

    CERN Document Server

    Ambjorn, Jan

    2014-01-01

    We study the geodesic two- and three-point functions of random weighted cubic maps, which are obtained by assigning random edge lengths to random cubic planar maps. Explicit expressions are obtained by taking limits of recently established bivariate multi-point functions of general planar maps. We give an alternative interpretation of the two-point function in terms of an Eden model exploration process on a random planar triangulation. Finally, the scaling limits of the multi-point functions are studied, showing in particular that the two- and three-point functions of the Brownian map are recovered as the number of faces is taken to infinity.

  7. Process for producing wurtzitic or cubic boron nitride

    International Nuclear Information System (INIS)

    Disclosed is a process for producing wurtzitic or cubic boron nitride comprising the steps of: [A] preparing an intimate mixture of powdered boron oxide, a powdered metal selected from the group consisting of magnesium or aluminum, and a powdered metal azide; [B] igniting the mixture and bringing it to a temperature at which self-sustaining combustion occurs; [C] shocking the mixture at the end of the combustion thereof with a high pressure wave, thereby forming as a reaction product, wurtzitic or cubic boron nitride and occluded metal oxide; and, optionally [D] removing the occluded metal oxide from the reaction product. Also disclosed are reaction products made by the process described

  8. Higher-spin Interactions from CFT: The Complete Cubic Couplings

    CERN Document Server

    Sleight, Charlotte

    2016-01-01

    In this letter we provide a complete holographic reconstruction of the cubic couplings in the minimal bosonic higher-spin theory in AdS$_{d+1}$. For this purpose we also determine the OPE coefficients of all single-trace conserved currents in the $d$-dimensional free scalar $O\\left(N\\right)$ vector model, and compute the tree-level three-point Witten diagram amplitudes for a generic cubic interaction of higher-spin gauge fields in the metric-like formulation.

  9. Image Compression and Reconstruction using Cubic Spline Interpolation Technique

    Directory of Open Access Journals (Sweden)

    R. Muthaiah

    2008-01-01

    Full Text Available A new dimension of image compression using random pixels of irregular sampling and image reconstruction using cubic-spline interpolation techniques proposed in this paper. It also covers the wide field of multimedia communication concerned with multimedia messaging (MMS and image transfer through mobile phones and tried to find a mechanism to transfer images with minimum bandwidth requirement. This method would provide a better efficiency both in pixel reconstruction and color reproduction. The discussion covers theoretical techniques of random pixel selection, transfer and implementation of efficient reconstruction with cubic spline interpolation.

  10. Classifying Cubic Edge-Transitive Graphs of Order 8

    Indian Academy of Sciences (India)

    Mehdi Alaeiyan; M K Hosseinipoor

    2009-11-01

    A simple undirected graph is said to be semisymmetric if it is regular and edge-transitive but not vertex-transitive. Let be a prime. It was shown by Folkman (J. Combin. Theory 3(1967) 215--232) that a regular edge-transitive graph of order 2 or 22 is necessarily vertex-transitive. In this paper, an extension of his result in the case of cubic graphs is given. It is proved that, every cubic edge-transitive graph of order 8 is symmetric, and then all such graphs are classified.

  11. Lice, body with stool (Pediculus humanus) (image)

    Science.gov (United States)

    ... capitis ), or the pubic area ( Phthirus pubis ). Some body lice may carry diseases such as epidemic typhus, relapsing fever, or trench fever. (Image courtesy of the Centers for Disease Control and ...

  12. Body contact and body language

    DEFF Research Database (Denmark)

    Winther, Helle Dagmar

    2008-01-01

    and the boundaries between self and world. In western societies, the modern premises for contact are in some ways developing from close contact to virtual communication. With this breadth of perspective in mind, the ques­tion is whether conscious and experimental work with body contact and body language in move......­ment psychology and education provide potential for intense personal develop­ment as well as for social and cultural learning processes. This performative research project originates from the research project entitled, Movement Psy­chol­ogy: The Language of the Body and the Psy­chol­ogy of Movement based...... on the Dance Therapy Form Dansergia. The author, who is a practi­tioner-researcher, is methodologically inspir­ed by phenomenology, performative methods and a narrative and auto-ethnographic approach. The project will be presented in an organic, cre­at­ive and performative way. Through a moving dia...

  13. Body counter

    International Nuclear Information System (INIS)

    The paper gives a survey on some applications of the whole body counter in clinical practice and a critical study of its application as a routine testing method. Remarks on the necessary precautions are followed by a more detailed discussion of the determination of the natural potassium content, the iron metabolism, the vitamin B12 test, investigations of the metabolism of the bone using 47Ca and 85Sr, investigations with iodine and iodine-labelled substances, clearance investigations (in particular the 51Cr EDTA clearance test), as well as the possibilities of neutron activation in vivo. (ORU/AK)

  14. National Health Information Center

    Science.gov (United States)

    ... ODPHP National Health Information Center National Health Information Center The National Health Information Center (NHIC) is sponsored ... interest View the NHO calendar . Federal Health Information Centers and Clearinghouses Federal Health Information Centers and Clearinghouses ...

  15. On the modification of the Efimov spectrum in a finite cubic box

    CERN Document Server

    Kreuzer, Simon

    2009-01-01

    Three particles with large scattering length display a universal spectrum of three-body bound states called "Efimov trimers''. We calculate the modification of the Efimov trimers of three identical bosons in a finite cubic box and compute the dependence of their energies on the box size using effective field theory. Previous calculations for positive scattering length that were perturbative in the finite volume energy shift are extended to arbitrarily large shifts and negative scattering lengths. The renormalization of the effective field theory in the finite volume is explicitly verified. Moreover, we investigate the effects of partial wave mixing and study the behavior of shallow trimers near the dimer energy. Finally, we provide numerical evidence for universal scaling of the finite volume corrections.

  16. Proton disorder in cubic ice: Effect on the electronic and optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Garbuio, Viviana; Pulci, Olivia [MIFP, ETSF, Physics Department of Tor Vergata University, Via della Ricerca Scientifica 1, I-00133 Rome (Italy); Cascella, Michele [Department of Chemistry and Centre for Theoretical and Computational Chemistry (CTCC), University of Oslo, Postboks 1033, Blindern, N-0315 Oslo (Norway); Kupchak, Igor [MIFP, V. Lashkarev Institute of Semiconductor Physics of National Academy of Sciences of Ukraine, pr. Nauki 45, UA-03680 Kiev (Ukraine); Seitsonen, Ari Paavo [Institut für Chemie, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich (Switzerland); Département de Chimie, École Normale Supérieure, 24 rue Lhomond, F-75005 Paris (France)

    2015-08-28

    The proton disorder in ice has a key role in several properties such as the growth mode, thermodynamical properties, and ferroelectricity. While structural phase transitions from proton disordered to proton ordered ices have been extensively studied, much less is known about their electronic and optical properties. Here, we present ab initio many body perturbation theory-based calculations of the electronic and optical properties of cubic ice at different levels of proton disorder. We compare our results with those from liquid water, that acts as an example of a fully (proton- and oxygen-)disordered system. We find that by increasing the proton disorder, a shrinking of the electronic gap occurs in ice, and it is smallest in the liquid water. Simultaneously, the excitonic binding energy decreases, so that the final optical gaps result to be almost independent on the degree of proton disorder. We explain these findings as an interplay between the local dipolar disorder and the electronic correlation.

  17. Foreign Body Retrieval

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Foreign Body Retrieval Foreign body retrieval is the removal ... of foreign body detection and removal? What is Foreign Body Retrieval? Foreign body retrieval involves the removal ...

  18. Integrability of Lotka-Volterra Planar Complex Cubic Systems

    Science.gov (United States)

    Dukarić, Maša; Giné, Jaume

    In this paper, we study the Lotka-Volterra complex cubic systems. We obtain necessary conditions of integrability for these systems with some restriction on the parameters. The sufficiency is proved for all conditions, except one which remains open, using different methods.

  19. Energy Transfer in Cubic PbF2:Gd Crystals

    Institute of Scientific and Technical Information of China (English)

    张国斌; 石军岩; 韩正甫; 施朝淑; 张新夷; 张增明; G. Zimmerer; M. Kirm; 沈定中

    2001-01-01

    The emission and excitation spectra of cubic PbF2 :Gd were measured. Compared with pure crystals, the emissionsfrom Gd3+ were observed upon cation exciton excitation in lattices, while the emission from intrinsic self-trappedexcitons was quenched. It indicates the energy transfer from exciton to the 4f state of Gd3+.

  20. Super-edge-graceful Labelings of Some Cubic Graphs

    Institute of Scientific and Technical Information of China (English)

    Wai Chee SHIU

    2006-01-01

    The notion of super-edge-graceful graphs was introduced by Mitchem and Simoson in 1994.However, few examples except trees are known. In this paper, we exhibit two classes of infinitely many cubic graphs which are super-edge-graceful. A conjecture is proposed.

  1. Rheology of cubic particles suspended in a Newtonian fluid.

    Science.gov (United States)

    Cwalina, Colin D; Harrison, Kelsey J; Wagner, Norman J

    2016-05-18

    Many real-world industrial processes involve non-spherical particles suspended in a fluid medium. Knowledge of the flow behavior of these suspensions is essential for optimizing their transport properties and designing processing equipment. In the present work, we explore and report on the rheology of concentrated suspensions of cubic-shaped colloidal particles under steady and dynamic shear flow. These suspensions exhibit a rich non-Newtonian rheology that includes shear thickening and normal stress differences at high shear stresses. Scalings are proposed to connect the material properties of these suspensions of cubic particle to those measured for suspensions of spherical particles. Negative first normal stress differences indicate that lubrication hydrodynamic forces dominate the stress in the shear-thickened state. Accounting for the increased lubrication hydrodynamic interactions between the flat surfaces of the cubic particles allows for a quantitative comparison of the deviatoric stress in the shear-thickened state to that of spherical particles. New semi-empirical models for the viscosity and normal stress difference coefficients are presented for the shear-thickened state. The results of this study indicate that cubic particles offer new and unique opportunities to formulate colloidal dispersions for field-responsive materials. PMID:27112791

  2. Morphosynthesis of cubic silver cages on monolithic activated carbon.

    Science.gov (United States)

    Wang, Fei; Zhao, Hong; Lai, Yijian; Liu, Siyu; Zhao, Binyuan; Ning, Yuesheng; Hu, Xiaobin

    2013-11-14

    Cubic silver cages were prepared on monolithic activated carbon (MAC) pre-absorbed with Cl(-), SO4(2-), or PO4(3-) anions. Silver insoluble salts served as templates for the morphosynthesis of silver cages. The silver ions were reduced by reductive functional groups on MAC micropores through a galvanic cell reaction mechanism. PMID:24080952

  3. Global Well-Posedness for Cubic NLS with Nonlinear Damping

    KAUST Repository

    Antonelli, Paolo

    2010-11-04

    We study the Cauchy problem for the cubic nonlinear Schrödinger equation, perturbed by (higher order) dissipative nonlinearities. We prove global in-time existence of solutions for general initial data in the energy space. In particular we treat the energy-critical case of a quintic dissipation in three space dimensions. © Taylor & Francis Group, LLC.

  4. Assessing Inquiry Learning: How Much Is a Cubic Metre?

    Science.gov (United States)

    Fry, Kym

    2014-01-01

    In this article, Kym Fry uses the "Programme for International Student Assessment" (PISA) assessment framework to break down what her Year 6 students learned as they explored the inquiry question, "How much is a cubic metre?" First, an overview of the lessons in the unit is provided. Quality assessment opportunities are…

  5. Physical vapor deposition of cubic boron nitride thin films

    International Nuclear Information System (INIS)

    Cubic boron nitride was successfully deposited using physical vapor-deposition methods. RF-sputtering, magnetron sputtering, dual-ion-beam deposition, and ion-beam-assisted evaporation were all used. The ion-assisted evaporation, using boron evaporation and bombardment by nitrogen and argon ions, led to successful cubic boron nitride growth over the widest and most controllable range of conditions. It was found that two factors were important for c-BN growth: bombardment of the growing film and the presence of argon. A systematic study of the deposition conditions was carried out. It was found that the value of momentum transferred into the growing from by the bombarding ions was critical. There was a very narrow transition range in which mixed cubic and hexagonal phase films were prepared. Momentum-per-atom value took into account all the variables involved in ion-assisted deposition: deposition rate, ion energy, ion flux, and ion species. No other factor led to the same control of the process. The role of temperature was also studied; it was found that at low temperatures only mixed cubic and hexagonal material are deposited

  6. Trapping of cubic ZnO nanocrystallites at ambient conditions

    DEFF Research Database (Denmark)

    Decremps, F.; Pellicer-Porres, J.; Datchi, F.;

    2002-01-01

    Dense powder of nanocrystalline ZnO has been recovered at ambient conditions in the metastable cubic structure after a heat treatment at high pressure (15 GPa and 550 K). Combined x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) experiments have been performed to probe both long-ra...

  7. Hardness and thermal stability of cubic silicon nitride

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Kragh, Flemming; Frost, D. J.;

    2001-01-01

    The hardness and thermal stability of cubic spinel silicon nitride (c-Si3N4), synthesized under high-pressure and high-temperature conditions, have been studied by microindentation measurements, and x-ray powder diffraction and scanning electron microscopy, respectively The phase at ambient...

  8. Global rough solutions to the cubic nonlinear Boussinesq equation

    OpenAIRE

    Farah, Luiz Gustavo; Linares, Felipe

    2008-01-01

    We prove that the initial value problem (IVP) for the cubic defocusing nonlinear Boussinesq equation $u_{tt}-u_{xx}+u_{xxxx}-(|u|^2u)_{xx}=0$ on the real line is globally well-posed in $H^{s}(\\R)$ provided $2/3

  9. Higher-Order Approximation of Cubic-Quintic Duffing Model

    DEFF Research Database (Denmark)

    Ganji, S. S.; Barari, Amin; Babazadeh, H.;

    2011-01-01

    We apply an Artificial Parameter Lindstedt-Poincaré Method (APL-PM) to find improved approximate solutions for strongly nonlinear Duffing oscillations with cubic-quintic nonlinear restoring force. This approach yields simple linear algebraic equations instead of nonlinear algebraic equations with...

  10. A Unified Approach to Teaching Quadratic and Cubic Equations.

    Science.gov (United States)

    Ward, A. J. B.

    2003-01-01

    Presents a simple method for teaching the algebraic solution of cubic equations via completion of the cube. Shows that this method is readily accepted by students already familiar with completion of the square as a method for quadratic equations. (Author/KHR)

  11. Compressibility and thermal expansion of cubic silicon nitride

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Lindelov, H.; Gerward, Leif;

    2002-01-01

    The compressibility and thermal expansion of the cubic silicon nitride (c-Si3N4) phase have been investigated by performing in situ x-ray powder-diffraction measurements using synchrotron radiation, complemented with computer simulations by means of first-principles calculations. The bulk...

  12. Cubical abelian groups with connections are equivalent to chain complexes

    OpenAIRE

    Brown, R.; Higgins, Philip J.

    2002-01-01

    The theorem of the title is deduced from the equivalence between crossed complexes and cubical $\\omega$-groupoids with connections proved by the authors in 1981. In fact we prove the equivalence of five categories defined internally to an additive category with kernels.

  13. Moufang loops of class 2 and cubic forms

    Science.gov (United States)

    Hsu, Tim

    2000-03-01

    We classify finite Moufang loops which are centrally nilpotent of class 2 in terms of certain cubic forms, concentrating on small Frattini Moufang loops, or SFMLs, which are Moufang loops L with a central subgroup Z of order p such that L/Z is an elementary abelian p-group. (For example, SFM 2-loops are precisely the class of code loops, in the sense of Griess.)More specifically, we first show that the nuclearly-derived subloop (normal associator subloop) of a Moufang loop of class 2 has exponent dividing 6. It follows that the subloop of elements of p-power order is associative for p > 3. Next, we show that if L is an SFML, then L/Z has the structure of a vector space with a symplectic cubic form. We then show that every symplectic cubic form is realized by some SFML and that two SFMLs are isomorphic in a manner preserving the central subgroup Z if and only if their symplectic cubic spaces are isomorphic up to scalar multiple. Consequently, we also obtain an explicit characterization of isotopy in SFM 3-loops. Finally, we extend many of our results to all finite Moufang loops of class 2.

  14. Centering research

    DEFF Research Database (Denmark)

    Katan, Lina Hauge; Baarts, Charlotte

    share as the common aim of both research and education. Despite some similarities, we find that how the two groups engage in and benefit from reading and writing diverges significantly. Thus we have even more reason to believe that centering practice-based teaching on these aspects of research is a good......’ exercises tend to dominate the common understandings of research-based learning. Here we address a specific area of inquiry overlooked by previous studies: whether and how reading, thinking and writing indeed share the same learning potentials as the practical foundation for research-based teaching....... In the humanities and social sciences, integrated acts of reading, writing and thinking account for an obvious and substantial overlap in student and researcher practices, creating a clear opportunity for research-based teaching. Moreover, our empirical data point to reading, thinking and writing as quintessential...

  15. Centering mount for a gamma camera

    International Nuclear Information System (INIS)

    A device for centering a γ-camera detector in case of radionuclide diagnosis is described. It permits the use of available medical coaches instead of a table with a transparent top. The device can be used for centering a detector (when it is fixed at the low end of a γ-camera) on a required area of the patient's body

  16. EPR observation of first point defects in cubic boron nitride crystalline powders

    Science.gov (United States)

    Nistor, S. V.; Stefan, M.; Schoemaker, D.; Dinca, G.

    2000-05-01

    An X-band electron paramagnetic resonance (EPR) study of nominally pure, diamond-like cubic boron nitride (c-BN) crystalline powders, has led to the first identification of a spectrum attributed to two related paramagnetic species. The composite EPR spectrum can be observed only in dark brown colored powders known to contain excess of boron. It consists of two superimposed lorentzian components, called D1 and D2, centered at g1=2.0063 and g2=2.0084, with peak-to-peak linewidths of 3.3 and 17.9 mT, respectively. The temperature dependence of the integrated intensities, their linewidths and intensity ratio D2/D1 allows one to conclude that the narrow line D1 originates from EPR transitions inside a S=1/2 ground doublet and the broad line D2 from transitions inside the excited levels of another center. Evidence suggests that both centers are boron related paramagnetic species.

  17. New Window into the Human Body

    Science.gov (United States)

    1985-01-01

    Michael Vannier, MD, a former NASA engineer, recognized the similarity between NASA's computerized image processing technology and nuclear magnetic resonance. With technical assistance from Kennedy Space Center, he developed a computer program for Mallinckrodt Institute of Radiology enabling Nuclear Magnetic Resonance (NMR) to scan body tissue for earlier diagnoses. Dr. Vannier feels that "satellite imaging" has opened a new window into the human body.

  18. A high-order adaptive Cartesian cut-cell method for simulation of compressible viscous flow over immersed bodies

    Science.gov (United States)

    Muralidharan, Balaji; Menon, Suresh

    2016-09-01

    A new adaptive finite volume conservative cut-cell method that is third-order accurate for simulation of compressible viscous flows is presented. A high-order reconstruction approach using cell centered piecewise polynomial approximation of flow quantities, developed in the past for body-fitted grids, is now extended to the Cartesian based cut-cell method. It is shown that the presence of cut-cells of very low volume results in numerical oscillations in the flow solution near the embedded boundaries when standard small cell treatment techniques are employed. A novel cell clustering approach for polynomial reconstruction in the vicinity of the small cells is proposed and is shown to achieve smooth representation of flow field quantities and their derivatives on immersed interfaces. It is further shown through numerical examples that the proposed clustering method achieves the design order of accuracy and is fairly insensitive to the cluster size. Results are presented for canonical flow past a single cylinder and a sphere at different flow Reynolds numbers to verify the accuracy of the scheme. Investigations are then performed for flow over two staggered cylinders and the results are compared with prior data for the same configuration. All the simulations are carried out with both quadratic and cubic reconstruction, and the results indicate a clear improvement with the cubic reconstruction. The new cut-cell approach with cell clustering is able to predict accurate results even at relatively low resolutions. The ability of the high-order cut-cell method in handling sharp geometrical corners and narrow gaps is also demonstrated using various examples. Finally, three-dimensional flow interactions between a pair of spheres in cross flow is investigated using the proposed cut-cell scheme. The results are shown to be in excellent agreement with past studies, which employed body-fitted grids for studying this complex case.

  19. Experimental evaluation of blockage ratio and plenum evacuation system flow effects on pressure distribution for bodies of revolution in 0.1 scale model test section of NASA Lewis Research Center's proposed altitude wind tunnel

    Science.gov (United States)

    Burley, Richard R.; Harrington, Douglas E.

    1987-01-01

    An experimental investigation was conducted in the slotted test section of the 0.1-scale model of the proposed Altitude Wind Tunnel to evaluate wall interference effects at tunnel Mach numbers from 0.70 to 0.95 on bodies of revolution with blockage rates of 0.43, 3, 6, and 12 percent. The amount of flow that had to be removed from the plenum chamber (which surrounded the slotted test section) by the plenum evacuation system (PES) to eliminate wall interference effects was determined. The effectiveness of tunnel reentry flaps in removing flow from the plenum chamber was examined. The 0.43-percent blockage model was the only one free of wall interference effects with no PES flow. Surface pressures on the forward part of the other models were greater than interference-free results and were not influenced by PES flow. Interference-free results were achieved on the aft part of the 3- and 6-percent blockage models with the proper amount of PES flow. The required PES flow was substantially reduced by opening the reentry flaps.

  20. Percepções de corpo identificadas entre pacientes e profissionais de medicina tradicional chinesa do Centro de Saúde Escola do Butantã Body perceptions identified among traditional chinese medicine patients and professionals from the Academic Health Center of Butantã

    Directory of Open Access Journals (Sweden)

    Maria Elisa Rizzi Cintra

    2012-03-01

    Full Text Available Esta pesquisa buscou compreender como profissionais de saúde e pacientes do Centro de Saúde Escola Samuel B. Pessoa/ Butantã (CSEB, localizado no município de São Paulo, percebem o corpo a partir do contato terapêutico com a Medicina Tradicional Chinesa (MTC. A investigação foi desenvolvida por meio de uma aproximação etnográfica no ambulatório de Acupuntura do CSEB, entre os meses de Setembro de 2008 e Abril de 2009. Foi identificada como central a oposição corpo saudável versus corpo não saudável. Permeadas por essa oposição, foram encontradas as seguintes dimensões: noções de corpo, reações do corpo e técnicas corporais. Percebeu-se que a partir da experiência com a MTC as pessoas passaram a considerar a possibilidade de um corpo no qual o estado energético e invisível antecede a matéria orgânica. O contato com a MTC permitiu que a pessoa conhecesse, na teoria e na prática, uma concepção de corpo diferenciada da concepção difundida pela biomedicina, e oferecesse outras explicações para as relações entre corpo/mente/emoção/sintomas, nas quais diversos aspectos de sua vida são levados em consideração, possibilitando transformações em suas técnicas de cuidado com o corpo.The present study aimed to understand how health professionals and patients from Centro de Saúde Escola Samuel B. Pessoa (CSEB - Academic Health Center Samuel B. Pessoa, located in the city of São Paulo, perceive the body in the therapeutic contact with the Traditional Chinese Medicine. This investigation was developed by means of an ethnographic approach in the acupuncture clinic of the CSEB, from September 2008 to April 2009. The opposition healthy body versus unhealthy body was identified as central. The following dimensions were found, permeated by this opposition: ideas of body, body reactions and body techniques. It was noted that, from the experience with Traditional Chinese Medicine, people started to consider the

  1. No predictive effect of body mass index on clinical response in patients with rheumatoid arthritis after 24 weeks of biological disease-modifying antirheumatic drugs: a single-center study.

    Science.gov (United States)

    Kim, Seong-Kyu; Choe, Jung-Yoon; Park, Sung-Hoon; Lee, Hwajeong

    2016-05-01

    The aim of this study was to determine whether body mass index (BMI) is associated with clinical response to biologics in patients with rheumatoid arthritis (RA). We enrolled 68 patients with RA who were treated with biological disease-modifying antirheumatic drugs (bDMARDs). Biologics included abatacept, tocilizumab, and tumor necrosis factor-α (TNF-α) blockers (etanercept and adalimumab). Baseline BMI (kg/m(2)) was classified as normal (BMI < 23.0), overweight (23.0 ≤ BMI < 25.0), or obese (BMI ≥ 25.0). Improvement of disease activity score 28 (DAS28) and achievement of the European League Against Rheumatism (EULAR) remission and responses between baseline and 24 weeks were our measures of clinical improvement. Mean baseline BMI before treatment with bDMARDs in patients with RA was 22.2 (SD 3.6). DAS28-ESR and DAS28-CRP were significantly reduced from baseline after 24 weeks of treatment with bDMARDs (p < 0.001 of both). ∆DAS28-ESR and ∆DAS28-CRP were not found among patients with normal, overweight, or obese BMI (p = 0.133 and p = 0.255, respectively) nor were EULAR responses or EULAR remission (p = 0.540 and p = 0.957, respectively). Logistic regression analysis showed no relationship of BMI with EULAR clinical responses (p = 0.093 for good response and p = 0.878 for EULAR remission). This study reveals that BMI is not a predictive factor of clinical response to bDMARDs in patients with RA. PMID:26932795

  2. Plasma simulation with the Differential Algebraic Cubic Interpolated Propagation scheme

    Energy Technology Data Exchange (ETDEWEB)

    Utsumi, Takayuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    A computer code based on the Differential Algebraic Cubic Interpolated Propagation scheme has been developed for the numerical solution of the Boltzmann equation for a one-dimensional plasma with immobile ions. The scheme advects the distribution function and its first derivatives in the phase space for one time step by using a numerical integration method for ordinary differential equations, and reconstructs the profile in phase space by using a cubic polynomial within a grid cell. The method gives stable and accurate results, and is efficient. It is successfully applied to a number of equations; the Vlasov equation, the Boltzmann equation with the Fokker-Planck or the Bhatnagar-Gross-Krook (BGK) collision term and the relativistic Vlasov equation. The method can be generalized in a straightforward way to treat cases such as problems with nonperiodic boundary conditions and higher dimensional problems. (author)

  3. A local cubic smoothing in an adaptation mode

    International Nuclear Information System (INIS)

    A new approach to a local curve approximation and the smoothing is proposed. The relation between curve points is defined using a special cross-ratio weight functions. The coordinates of three curve points are used as parameters for both the weight functions and the tree-point cubic model (TPS). A very simple in computing and stable to random errors cubic smoother in an adaptation mode (LOCUS) is constructed. The free parameter of TPS is estimated independently of the fixed parameters by recursion with the effective error suppression and can be controlled by the cross-ratio parameters. Efficiency and the noise stability of the algorithm are confirmed by examples and by comparison with other known non-parametric smoothers

  4. 3D Medical Image Interpolation Based on Parametric Cubic Convolution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In the process of display, manipulation and analysis of biomedical image data, they usually need to be converted to data of isotropic discretization through the process of interpolation, while the cubic convolution interpolation is widely used due to its good tradeoff between computational cost and accuracy. In this paper, we present a whole concept for the 3D medical image interpolation based on cubic convolution, and the six methods, with the different sharp control parameter, which are formulated in details. Furthermore, we also give an objective comparison for these methods using data sets with the different slice spacing. Each slice in these data sets is estimated by each interpolation method and compared with the original slice using three measures: mean-squared difference, number of sites of disagreement, and largest difference. According to the experimental results, we present a recommendation for 3D medical images under the different situations in the end.

  5. Synthesis of nanocrystalline cubic zirconia using femtosecond laser ablation

    International Nuclear Information System (INIS)

    We report on the synthesis of nanocrystalline zirconia in liquid using femtosecond laser ablation. Nanocrystalline cubic zirconia has been prepared by femtosecond laser ablation of zirconium in ammonia, while nanocrystalline tetragonal and monoclinic zirconia was synthesized in water. The physical and chemical mechanisms of the formation of nanocrystalline metastable zirconia are discussed. The intrinsic properties of femtosecond laser ablation in liquid and OH−1 may be responsible for the synthesis of cubic zirconia. It is suggested that the femtosecond laser pulse can create higher temperature and pressure conditions at a localized area in the liquid than the nanosecond laser pulse and the cooling is also faster in the femtosecond laser ablation process, which determined the difference between the products synthesized with femtosecond and nanosecond-pulsed laser ablation.

  6. Global Sufficient Optimality Conditions for a Special Cubic Minimization Problem

    Directory of Open Access Journals (Sweden)

    Xiaomei Zhang

    2012-01-01

    Full Text Available We present some sufficient global optimality conditions for a special cubic minimization problem with box constraints or binary constraints by extending the global subdifferential approach proposed by V. Jeyakumar et al. (2006. The present conditions generalize the results developed in the work of V. Jeyakumar et al. where a quadratic minimization problem with box constraints or binary constraints was considered. In addition, a special diagonal matrix is constructed, which is used to provide a convenient method for justifying the proposed sufficient conditions. Then, the reformulation of the sufficient conditions follows. It is worth noting that this reformulation is also applicable to the quadratic minimization problem with box or binary constraints considered in the works of V. Jeyakumar et al. (2006 and Y. Wang et al. (2010. Finally some examples demonstrate that our optimality conditions can effectively be used for identifying global minimizers of the certain nonconvex cubic minimization problem.

  7. Highly Aminated Mesoporous Silica Nanoparticles with Cubic Pore Structure

    KAUST Repository

    Suteewong, Teeraporn

    2011-01-19

    Mesoporous silica with cubic symmetry has attracted interest from researchers for some time. Here, we present the room temperature synthesis of mesoporous silica nanoparticles possessing cubic Pm3n symmetry with very high molar ratios (>50%) of 3-aminopropyl triethoxysilane. The synthesis is robust allowing, for example, co-condensation of organic dyes without loss of structure. By means of pore expander molecules, the pore size can be enlarged from 2.7 to 5 nm, while particle size decreases. Adding pore expander and co-condensing fluorescent dyes in the same synthesis reduces average particle size further down to 100 nm. After PEGylation, such fluorescent aminated mesoporous silica nanoparticles are spontaneously taken up by cells as demonstrated by fluorescence microscopy.

  8. Dementia with Lewy Bodies

    Science.gov (United States)

    ... Awards Enhancing Diversity Find People About NINDS NINDS Dementia With Lewy Bodies Information Page Synonym(s): Lewy Body ... and Information Additional resources from MedlinePlus What is Dementia With Lewy Bodies? Dementia with Lewy bodies (DLB) ...

  9. A highly ordered cubic mesoporous silica/graphene nanocomposite

    Science.gov (United States)

    Lee, Chang-Wook; Roh, Kwang Chul; Kim, Kwang-Bum

    2013-09-01

    A highly ordered cubic mesoporous silica (KIT-6)/graphene nanocomposite and 2D KIT-6 nanoflakes were synthesized using a novel synthesis methodology. The non-ionic triblock copolymer, P123, played a dual role as a structure-directing agent in the formation of the cubic mesoporous structure and as a cross-linking agent between mesoporous silica and graphene. The prepared (KIT-6)/graphene nanocomposite could act as a template for the preparation of mesoporous material/graphene nanocomposites.A highly ordered cubic mesoporous silica (KIT-6)/graphene nanocomposite and 2D KIT-6 nanoflakes were synthesized using a novel synthesis methodology. The non-ionic triblock copolymer, P123, played a dual role as a structure-directing agent in the formation of the cubic mesoporous structure and as a cross-linking agent between mesoporous silica and graphene. The prepared (KIT-6)/graphene nanocomposite could act as a template for the preparation of mesoporous material/graphene nanocomposites. Electronic supplementary information (ESI) available: S1: TEM images of disordered mesoporous silica/graphene nanocomposite; S2: TEM images of KIT-6/GO nanocomposite; S3: Thermogravimetric analysis of KIT-6/GO and KG-400-700; S4: SEM and TEM images of KIT-6; S5: Low angle XRD, Raman spectra, N2 adsorption isotherms, pore size distribution and photographic images of the prepared samples; S6: TEM image and N2 adsorption isotherms of mesoporous carbon/graphene nanocomposite; S7: XPS C1s spectra of the prepared samples. See DOI: 10.1039/c3nr03108j

  10. INTEGRABILITY AND LINEARIZABILITY FOR A CLASS OF CUBIC KOLMOGOROV SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The integrability and linearizability for a class of cubic Kolmogorov systems are studied. A recursive formula to compute the saddle quantities of the systems is deduced firstly, and integrable conditions for the systems are obtained. Then a recursive formula to compute the coefficients of the normal form for saddle points of the systems is also applied. Finally linearizable conditions of the origin for the systems are given. Both formulas to find necessary conditions are all linear and readily done using c...

  11. The effects of cubic damping on vibration isolation

    OpenAIRE

    Panananda, Nuttarut

    2014-01-01

    Vibration isolators are often assumed to possess linear viscous damping which has well known consequences for their performance. However, damping may be designed to be or prove to be nonlinear. This study investigates the effect of cubic damping, as an example of damping nonlinearity, in a single degree of freedom (SDOF) vibration isolation system. The response behaviour due to two excitation types, namely harmonic and broadband excitations, was examined. For harmonic excitation, the Harm...

  12. A resurgence analysis for cubic and quartic anharmonic potentials

    CERN Document Server

    Gahramanov, Ilmar

    2016-01-01

    In this work we explicitly show resurgence relations between perturbative and one instanton sectors of the resonance energy levels for cubic and quartic anharmonic potentials in one-dimensional quantum mechanics. Both systems satisfy the Dunne-Unsal relation and hence we are able to derive one-instanton non-perturbative contributions with the fluctuation terms to the energy merely from the perturbative data. We confirm our results with previous results obtained by Zinn-Justin et al.

  13. Interfacial reaction rates and free energy of cubic clusters

    OpenAIRE

    Lepinoux, Joel

    2004-01-01

    Abstract A new formulation of interfacial reaction rates for clusters in binary alloys is presented. It accounts for the matrix structure and the topological properties of cluster at the atomic scale. It is shown that the probabilities per unit time that a solute atom be captured or released by a cluster are functions of the partition function but also of a transition function. The principles of calculation of these functions are general but only the case of cubic clusters is treat...

  14. Inhomogeneous atomic Bose-Fermi mixtures in cubic lattices

    OpenAIRE

    Cramer, M.; Eisert, J.; Illuminati, F.

    2003-01-01

    We determine the ground state properties of inhomogeneous mixtures of bosons and fermions in cubic lattices by studying the Bose-Fermi Hubbard model including parabolic confining potentials. We present the exact solution in the limit of vanishing hopping (ultradeep lattices) and study the resulting domain structure of composite particles. For finite hopping we determine the domain boundaries between Mott-insulator plateaux and hopping-dominated regions for lattices of arbitrary dimensionality...

  15. Line-graphs of cubic graphs are normal

    OpenAIRE

    Patakfalvi, Zsolt

    2006-01-01

    A graph is called normal if its vertex set can be covered by cliques and also by stable sets, such that every such clique and stable set have non-empty intersection. This notion is due to Korner, who introduced the class of normal graphs as an extension of the class of perfect graphs. Normality has also relevance in information theory. Here we prove, that the line graphs of cubic graphs are normal.

  16. Anodic etching of p-type cubic silicon carbide

    Science.gov (United States)

    Harris, G. L.; Fekade, K.; Wongchotigul, K.

    1992-01-01

    p-Type cubic silicon carbide was anodically etched using an electrolyte of HF:HCl:H2O. The etching depth was determined versus time with a fixed current density of 96.4 mA/sq cm. It was found that the etching was very smooth and very uniform. An etch rate of 22.7 nm/s was obtained in a 1:1:50 HF:HCl:H2O electrolyte.

  17. Tensorial Representation of the Orientation Distribution Function in Cubic Polycrystals

    OpenAIRE

    Guidi, Maurizio; Adams, Brent L.; Onat, E. Turan

    1992-01-01

    A precise definition for the crystallite orientation distribution function (codf) of cubic polycrystals is given in terms of the set of distinct orientations of a cube. Elements of the classical Fourier representation of the codf, in terms of (symmetrized) generalized spherical harmonics, are reviewed. An alternative Fourier representation is defined in which the coefficients of the series expansion are irreducible tensors. Since tensors can be defined without the benefit of a coordinate fram...

  18. Taylor line swimming in microchannels and cubic lattices of obstacles

    OpenAIRE

    Münch, Jan L.; Alizadehrad, Davod; Babu, Sujin; Stark, Holger

    2016-01-01

    Microorganisms naturally move in microstructured fluids. Using the simulation method of multi-particle collision dynamics, we study an undulatory Taylor line swimming in a two-dimensional microchannel and in a cubic lattice of obstacles, which represent simple forms of a microstructured environment. In the microchannel the Taylor line swims at an acute angle along a channel wall with a clearly enhanced swimming speed due to hydrodynamic interactions with the bounding wall. While in a dilute o...

  19. Coding Side-Information for Implementing Cubic Transformation

    OpenAIRE

    Reddy, B. Prashanth

    2015-01-01

    This paper considers the implementation of the cubic public-key transformation, a public-key cryptographic scheme that requires sending of additional side-information. A coding scheme for the side-information, based on the residue number system, is presented. In the conventional one-to-one encryption mapping also, such coding can be used to send additional like that of watermarking, which could be used to detect man-in-the-middle attacks or used for authentication.

  20. Vortex solitons under competing nonlocal cubic and local quintic nonlinearities

    International Nuclear Information System (INIS)

    Vortex solitons in nonlinear media with competing nonlocal self-focusing cubic and local self-defocusing quintic nonlinearities are studied analytically and numerically. By using an approximate variational approach, we obtain bifurcated solutions of the vortex solitons with the upper (lower) branch carrying larger (smaller) power stemmed by the competing effect between cubic and quintic nonlinearities. Besides the better stability of vortex solitons due to the competing effect, similar to the dynamics of the vortex solitons in the media with single nonlocal cubic nonlinearity only, the vortex solitons located in the lower branch always split into multipole scalar solitons in the limit of weak nonlocality and propagate stably when the degree of nonlocality is sufficiently strong. On the other hand, the internal modes of the vortex solitons in the upper branch are always unstable, and will break up into rings or spots of particle clusters. The dynamics and the stability of the vortex solitons are numerically demonstrated with the split-step Fourier transform method. (paper)

  1. Cubic and Hexagonal Liquid Crystals as Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Yulin Chen

    2014-01-01

    Full Text Available Lipids have been widely used as main constituents in various drug delivery systems, such as liposomes, solid lipid nanoparticles, nanostructured lipid carriers, and lipid-based lyotropic liquid crystals. Among them, lipid-based lyotropic liquid crystals have highly ordered, thermodynamically stable internal nanostructure, thereby offering the potential as a sustained drug release matrix. The intricate nanostructures of the cubic phase and hexagonal phase have been shown to provide diffusion controlled release of active pharmaceutical ingredients with a wide range of molecular weights and polarities. In addition, the biodegradable and biocompatible nature of lipids demonstrates the minimum toxicity and thus they are used for various routes of administration. Therefore, the research on lipid-based lyotropic liquid crystalline phases has attracted a lot of attention in recent years. This review will provide an overview of the lipids used to prepare cubic phase and hexagonal phase at physiological temperature, as well as the influencing factors on the phase transition of liquid crystals. In particular, the most current research progresses on cubic and hexagonal phases as drug delivery systems will be discussed.

  2. Martensitic and austenitic transformations in core-surface cubic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Özüm, S. [Institute of Sciences, Niğde University, 51240 Niğde (Turkey); Yalçın, O., E-mail: o.yalcin@nigde.edu.tr [Department of Physics, Niğde University, 51240 Niğde (Turkey); Erdem, R. [Department of Physics, Akdeniz University, 07058 Antalya (Turkey); Bayrakdar, H. [Department of Materials Science and Engineering, Çanakkale Onsekiz Mart University, 17000 Çanakkale (Turkey); Eker, H.N. [Institute of Sciences, Niğde University, 51240 Niğde (Turkey)

    2015-01-01

    As a continuation of our recently published work, we have used the pair approximation in Kikuchi version to investigate martensitic and austenitic transformations in homogeneous (HM) and composite (CM) cubic nanoparticles (CNPs) based on the Blume–Emery–Griffiths model. A single cubic nanoparticle made of a core surrounded by a surface is considered as shaped in two dimensional (2D) square arrays instead of hexagonal array. From the phase diagrams of HM and CM-CNPs it has been observed that the martensitic–austenitic transformations (MT–AT) occurred. The influence of the exchange coupling and single-ion anisotropy parameters in the model Hamiltonian on the MT–AT is studied and analyzed in comparison with the results for hexagonal nanoparticles. Significant changes of the phase transition points and hysteresis behaviours depending upon the particle structure have been discussed. - Highlights: • This paper realized cubic nanoparticles. • This nanoparticles are investigated with single-ion anisotropy. • The hysteretic splitting are plotted.

  3. Cl- induced synthesis of submicron cubic copper particles in solution

    Institute of Scientific and Technical Information of China (English)

    Minyi Hu; Kanggen Zhou; Chongguo Wang; Rui Xu

    2008-01-01

    Submicron copper microcrystal was synthesized by reducing Cu2O with hydrazine hydrate as reducer in aqueous solution,and was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The shapes of copper microcrystai de-pend on additives. Cubic copper particles were observed when the inorganic salt containing Cl-, such as NH4Cl, NaCl, or KCl, was added into the reaction system. By combined use of NH4Cl and polyvinylpyrrolidone (PVP), the proportion of cubic copper particle number exceeded 90%, and the particle size is 0.1~0.5 μm. While other inorganic salt without Ci-, such as Na2SO4 or (NH4)2SO4,had little effect on the shapes of the copper particles. The growth mechanism of metallic copper crystal in aqueous solution was ana-lyzed. It is suggested that the formation of cubic copper crystals is ascribed to the selective adsorption of Cl- on copper crystal (100)faces.

  4. Dry Powder Precursors of Cubic Liquid Crystalline Nanoparticles (cubosomes)

    International Nuclear Information System (INIS)

    Cubosomes are dispersed nanostructured particles of cubic phase liquid crystal that have stimulated significant research interest because of their potential for application in controlled-release and drug delivery. Despite the interest, cubosomes can be difficult to fabricate and stabilize with current methods. Most of the current work is limited to liquid phase processes involving high shear dispersion of bulk cubic liquid crystalline material into sub-micron particles, limiting application flexibility. In this work, two types of dry powder cubosome precursors are produced by spray-drying: (1) starch-encapsulated monoolein is produced by spray-drying a dispersion of cubic liquid crystalline particles in an aqueous starch solution and (2) dextran-encapsulated monoolein is produced by spray-drying an emulsion formed by the ethanol-dextran-monoolein-water system. The encapsulants are used to decrease powder cohesion during drying and to act as a soluble colloidal stabilizer upon hydration of the powders. Both powders are shown to form (on average) 0.6 μm colloidally-stable cubosomes upon addition to water. However, the starch powders have a broader particle size distribution than the dextran powders because of the relative ease of spraying emulsions versus dispersions. The developed processes enable the production of nanostructured cubosomes by end-users rather than just specialized researchers and allow tailoring of the surface state of the cubosomes for broader application

  5. Martensitic and austenitic transformations in core-surface cubic nanoparticles

    International Nuclear Information System (INIS)

    As a continuation of our recently published work, we have used the pair approximation in Kikuchi version to investigate martensitic and austenitic transformations in homogeneous (HM) and composite (CM) cubic nanoparticles (CNPs) based on the Blume–Emery–Griffiths model. A single cubic nanoparticle made of a core surrounded by a surface is considered as shaped in two dimensional (2D) square arrays instead of hexagonal array. From the phase diagrams of HM and CM-CNPs it has been observed that the martensitic–austenitic transformations (MT–AT) occurred. The influence of the exchange coupling and single-ion anisotropy parameters in the model Hamiltonian on the MT–AT is studied and analyzed in comparison with the results for hexagonal nanoparticles. Significant changes of the phase transition points and hysteresis behaviours depending upon the particle structure have been discussed. - Highlights: • This paper realized cubic nanoparticles. • This nanoparticles are investigated with single-ion anisotropy. • The hysteretic splitting are plotted

  6. Energy spectra of small two-component Fermi gases in a cubic box with periodic boundary conditions

    Science.gov (United States)

    Yin, X. Y.; Blume, D.

    2013-05-01

    The properties of two-component Fermi gases become universal if the interspecies s-wave scattering length and the average interparticle spacing are much larger than the range of the underlying two-body potential. Using an explicitly correlated Gaussian basis set expansion approach, we determine the eigenenergies of two-component Fermi gases in a cubic box with periodic boundary conditions as functions of the interspecies s-wave scattering length and the effective range of the two-body potential. The universal properties of systems consisting of up to five particles are determined by extrapolating the finite-range energies to the zero-range limit. We determine the eigenenergies of states with vanishing and finite momentum. For the infinitely large scattering length case, we compare our results with those presented in the literature. Support by the ARO is gratefully acknowledged.

  7. Functional Web Testing Automation with CubicTest%Web功能自动化测试工具CubicTest

    Institute of Scientific and Technical Information of China (English)

    金名言

    2012-01-01

    该文简要介绍了CubicTest作为最简单的网页功能自动化测试解决方案之一,通过与功能更全的QTP比较来突出其优点与缺点.使用开放源码软件来替代QTP的知识,在为客户提供咨询时十分有用.最后,提供了一个开发的框架,以补充CubicTest和Selenium所不能提供的功能.这里还有很多可提高的余地,感谢那些来自论坛的优秀的软件架构师的贡献.

  8. Decontamination of body surface

    International Nuclear Information System (INIS)

    There are two important points for an effective application of decontamination procedures. One is the organizing method of responsible decontamination teams. The team should be directed by medical doctor with the knowledge of decontamination of radionuclides. The other point is the place of application of the decontamination. Hospitals and clinics, especially with a department of nuclear medicine, or specialized units such as an emergency medical center are preferable. Before decontamination procedures are initiated, adequate monitoring of the body surface should be undertaken by a competent person in order to demarcate the areas which are contaminated. There are fundamental principles which are applicable to all decontamination procedures. (1) Precautions must always be taken to prevent further spread of contamination during decontamination operations. (2) Mild decontamination methods should be tried before resorting to treatment which can damage the body surface. The specific feature of each contamination varies widely in radionuclides involved, place and area of the contamination, condition of the contaminated skin such as whether the skin is wounded or not, and others. Soap and water are usually good detergents in most cases. If they fail, orange oil cream (SUPERDECONCREAM, available from Tokyo Engineering Co.) specially prepared for decontamination of radionuclides of most fission and corrosion products may be used. Contaminated hair should be washed several times with an efficient shampoo. (author)

  9. Small two-component Fermi gases in a cubic box with periodic boundary conditions

    Science.gov (United States)

    Yin, X. Y.; Blume, D.

    2013-06-01

    The properties of two-component Fermi gases become universal if the interspecies s-wave scattering length as and the average interparticle spacing are much larger than the range of the underlying two-body potential. Using an explicitly correlated Gaussian basis set expansion approach, we determine the eigenenergies of two-component Fermi gases in a cubic box with periodic boundary conditions as functions of the interspecies s-wave scattering length and the effective range of the two-body potential. The universal properties of systems consisting of up to four particles are determined by extrapolating the finite-range energies to the zero-range limit. We determine the eigenenergies of states with vanishing and finite momenta. In the weakly attractive BCS regime, we analyze the energy spectra and degeneracies using first-order degenerate perturbation theory. Excellent agreement between the perturbative energy shifts and the numerically determined energies is obtained. For the infinitely large scattering length case, we compare our results—where available—with those presented in the literature.

  10. Structure and properties of rhombohedral CePd3Ga8: A variant of the cubic parent compound with BaHg11 structure type

    International Nuclear Information System (INIS)

    Single crystals of a new intermetallic gallide, R-CePd3Ga8, have been synthesized from excess molten gallium. Single-crystal X-ray diffraction reveals that R-CePd3Ga8 crystallizes in the R-3m space group with a=b=c=8.4903(10) Å and α=β=γ=89.993(17). R-CePd3Ga8 is a variant of the cubic BaHg11 structure type with three structural units: a Ce-centered polyhedron, a distorted cube of Pd2Ga6 and a Pd-centered cuboctahedron. The distortions of these units are compared to undistorted analogous units in intermetallic compounds with BaHg11 structure type. Field and temperature-dependent magnetization measurements on R-CePd3Ga8 reveal a paramagnetic material with strong antiferromagnetic correlations and a magnetization consistent with Ce3+. Electrical resistance measurements indicate Kondo behavior between localized Ce3+ magnetic moments. - Graphical Abstract: Single crystals of CePd3Ga8 have been synthesized from Ga flux. This new compound is the first rhombohedral variant of the cubic BaHg11 structure type. Highlights: ▶ Single crystals of CePd3Ga8 were synthesized from gallium flux. ▶ CePd3Ga8 is the first rhombohedral variant of the cubic BaHg11 structure type. ▶ Paramagnetic with antiferromagnetic correlations. ▶ Magnetization consistent with Ce3+.

  11. Call Center ist nicht gleich Call Center

    OpenAIRE

    Baumgartner, Marc; Udris, Ivars

    2005-01-01

    Untersuchungen in 14 Schweizer Call Centers erbrachten vier Call Center-Typen, die sich hinsichtlich Arbeitstätigkeiten und Kommunikationsrichtung voneinander unterscheiden: (a) Beratungs- und Beschwerdemanagement, (b) Informationsmanagement, (c) Auftragsmanagement und (d) Kunden- und Kampagnenmanagement. Dies hat auch Auswirkungen auf die Personalstruktur, -selektion und -entwicklung der Call Center. Es wird der Frage nachgegangen, welche Kompetenzanforderungen in den unterschiedlichen Call ...

  12. Scattering for the radial 3d cubic wave equation

    OpenAIRE

    Dodson, Benjamin; Lawrie, Andrew

    2014-01-01

    Consider the Cauchy problem for the radial cubic wave equation in 1+3 dimensions with either the focusing or defocusing sign. This problem is critical in $\\dot{H}^{\\frac{1}{2}} \\times \\dot{H}^{-\\frac{1}{2}}$ and subcritical with respect to the conserved energy. Here we prove that if the critical norm of a solution remains bounded on the maximal time-interval of existence, then the solution must in fact be global-in-time and scatter to free waves as $t \\to \\pm \\infty$.

  13. Elasticity tensor and ultrasonic velocities for anisotropic cubic polycrystal

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The orientation distribution of crystallites in a polycrystal can be described by the orientation distribution function(ODF) . The ODF can be expanded under the Wigner D-bases. The expanded coefficients in the ODF are called the texture coefficients. In this paper,we use the Clebsch-Gordan expression to derive an explicit expression of the elasticity tensor for an anisotropic cubic polycrystal. The elasticity tensor contains three material constants and nine texture coefficients. In order to measure the nine texture coefficients by ultrasonic wave,we give relations between the nine texture coefficients and ultrasonic propagation velocities. We also give a numerical example to check the relations.

  14. Research on the Cutting Performance of Cubic Boron Nitride Tools

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    There were only two kinds of superhard tool material at the past, i.e. diamond and cubic boron nitride (CBN). Manmade diamond and CBN are manufactured by the middle of 20th century. Various manufacturing methods and manmade superhard materials were developed later. They were widely used in different industry and science areas. Recently, a new kind of superhard tool material, C 3N 4 coating film, had been developed. American physical scientists, A. M. Liu and M. L. Cohen, designed a new kind of inorganic c...

  15. Multi-dimensional cubic interpolation for ICF hydrodynamics simulation

    International Nuclear Information System (INIS)

    A new interpolation method is proposed to solve the multi-dimensional hyperbolic equations which appear in describing the hydrodynamics of inertial confinement fusion (ICF) implosion. The advection phase of the cubic-interpolated pseudo-particle (CIP) is greatly improved, by assuming the continuities of the second and the third spatial derivatives in addition to the physical value and the first derivative. These derivatives are derived from the given physical equation. In order to evaluate the new method, Zalesak's example is tested, and we obtain successfully good results. (author)

  16. Theoretical and Experimental Study of Time Reversal in Cubic Crystals

    Institute of Scientific and Technical Information of China (English)

    陆铭慧; 张碧星; 汪承灏

    2004-01-01

    The self-adaptive focusing of the time reversal in anisotropic media is studied theoretically and experimentally. It is conducted for the compressional wave field in the cubic crystal silicon. The experimental result is in agreement with our theoretical analysis. The focusing gain and the displacement distributions of the time reversal field are analysed in detail. It is shown that the waves from different elements of the transducer array arrive at the original place of the source simultaneously after the time reversal operation. The waveform distortions caused by the velocity anisotropy can automatically be compensated for after the time reversal processing.

  17. Probabilistic well-posedness for the cubic wave equation

    CERN Document Server

    Burq, Nicolas

    2011-01-01

    The purpose of this article is to introduce for dispersive partial differential equations with random initial data, the notion of well-posedness (in the Hadamard-probabilistic sense). We restrict the study to one of the simplest examples of such equations: the periodic cubic semi-linear wave equation. Our contributions in this work are twofold: first we break the algebraic rigidity involved in previous works and allow much more general randomizations (general infinite product measures v.s. Gibbs measures), and second, we show that the flow that we are able to construct enjoys very nice dynamical properties, including a new notion of probabilistic continuity.

  18. Inhomogeneous atomic Bose-Fermi mixtures in cubic lattices

    International Nuclear Information System (INIS)

    We determine the ground state properties of inhomogeneous mixtures of bosons and fermions in cubic lattices and parabolic confining potentials. For finite hopping we determine the domain boundaries between Mott-insulator plateaux and hopping-dominated regions for lattices of arbitrary dimension within mean-field and perturbation theory. The results are compared with a new numerical method that is based on a Gutzwiller variational approach for the bosons and an exact treatment for the fermions. The findings can be applied as a guideline for future experiments with trapped atomic Bose-Fermi mixtures in optical lattices

  19. Preparation and characterization of thick cubic boron nitride films

    International Nuclear Information System (INIS)

    Cubic boron nitride (c-BN) films are prepared by the radio frequency magnetron sputtering technique. The stresses and crystallinities of the films are estimated by the Fourier transform infrared spectroscopy of c-BN samples, including the peak shifts and varieties of full widths at half maximum. The effects of the B—C—N interlayer and the two-stage deposition method on the c-BN films are investigated. Then the thick and stable c-BN films are prepared by a combination of the two methods. The properties of the interlayer and film are also characterized

  20. Cubature Formula and Interpolation on the Cubic Domain

    Institute of Scientific and Technical Information of China (English)

    Huiyuan Li; Jiachang Sun; Yuan Xu

    2009-01-01

    Several cubature formulas on the cubic domains are derived using the dis-crete Fourier analysis associated with lattice tiling, as developed in [10]. The main results consist of a new derivation of the Gaussian type cubature for the product Cheby-shev weight functions and associated interpolation polynomials on [-1,1]2, as well as new results on [-1,1]3. In particular, compact formulas for the fundamental interpo-lation polynomials are derived, based on n3/4 + (n2) nodes of a cubature formula on [-1,1]3.

  1. Growth Mechanism of Cubic-Silicon Carbide Nanowires

    Directory of Open Access Journals (Sweden)

    K. Y. Cheong

    2009-01-01

    Full Text Available Cubic-SiC nanowires were synthesized using activated carbon powder and Si substrate in vacuum at 1200–1350°C for 1–4 hours. The nanowires were grown according to the following proposed mechanisms: (1 diffusion of C/CO into Si substrate, (2 weakening of Si bond and atomic kick-out, (3 formation of Si-C in vapor phase, (4 formation of saturated SiC layer, (5 formation of pyramid-like SiC nanostructure, and (6 formation of SiC nanowires.

  2. Cubic to tetragonal crystal lattice reconstruction during ordering or decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Byung-kl [Carnegie-Mellon Univ., Pittsburgh, PA (United States). Dept. of Materials Science and Engineering

    1992-09-01

    This thesis studied thermodynamic stability and morphology of product phases in diffusional phase transformations involving cubic-to-tetragonal crystal lattice reconstructions. Two different kinds of diffusional transformations were examined: L1{sub 0} ordering (fcc to fct lattice change) and decomposition of off-stoichiometric B2 ordering alloys accompanying bcc to fcc Bain transformation. In the first case, Fe-45 at.% Pd alloys were studied by TEM; in the second, the Bain strain relaxation during decomposition of hyper-eutectoid Cu-9.04 wt% Be alloy was studied. CuAu and InMg were also studied.

  3. Soliton interaction in quadratic and cubic bulk media

    DEFF Research Database (Denmark)

    Johansen, Steffen Kjær; Bang, Ole

    2000-01-01

    Summary form only given. The understanding of how and to what extend the cubic nonlinearity affects beam propagation and spatial soliton formation in quadratic media is of vital importance in fundamental and applied nonlinear physics. We consider beam propagation under type-I SHG conditions in...... lossless bulk second order nonlinear optical materials with a nonvanishing third order nonlinearity. It is known that in pure second order systems a single soliton can never collapse whereas in systems with both nonlinearities and that stable single soliton propagation can only in some circumstances be...

  4. X-Ray Elastic Constants for Cubic Materials

    International Nuclear Information System (INIS)

    The stress-strain relation to be used in X-ray stress measurements in anisotropic texture-free media is studied. The method for evaluation of appropriate elastic constants for a cubic medium is described. Some illustrative numerical examples have been worked out including line broadening due to elastic anisotropy. The elastic stress and strain compatibility at grain boundaries is taken into account using Kroner's method. These elastic constants obviously only apply when no internal stresses due to plastic deformation are present. The case of reorientation of free interstitials in the stress field can be taken into account

  5. Inhomogeneous atomic Bose-Fermi mixtures in cubic lattices.

    Science.gov (United States)

    Cramer, M; Eisert, J; Illuminati, F

    2004-11-01

    We determine the ground state properties of inhomogeneous mixtures of bosons and fermions in cubic lattices and parabolic confining potentials. For finite hopping we determine the domain boundaries between Mott-insulator plateaux and hopping-dominated regions for lattices of arbitrary dimension within mean-field and perturbation theory. The results are compared with a new numerical method that is based on a Gutzwiller variational approach for the bosons and an exact treatment for the fermions. The findings can be applied as a guideline for future experiments with trapped atomic Bose-Fermi mixtures in optical lattices. PMID:15600816

  6. Ionic Conduction in Cubic Zirconias at Low Temperatures

    Institute of Scientific and Technical Information of China (English)

    Ying LI; Yunfa CHEN; Jianghong GONG

    2004-01-01

    The ac conductivities of Y2O3 or CaO-stabilized cubic zirconias were obtained from complex impedance measurements in the temperature range from 373 to 473 K. By analyzing the temperature-dependence of the resultant dc conductivities, it was shown that the activation energies for conduction are lower than those reported previously for the same materials at high temperatures. Comparing the activation energy data with the theoretically estimated values revealed that there may exist a certain, although very small, amount of free oxygen vacancies in the test samples at low temperatures and the conduction in the test samples is a result of the migration of these free oxygen vacancies.

  7. Bistable Helmholtz solitons in cubic-quintic materials

    International Nuclear Information System (INIS)

    We propose a nonlinear Helmholtz equation for modeling the evolution of broad optical beams in media with a cubic-quintic intensity-dependent refractive index. This type of nonlinearity is appropriate for some semiconductor materials, glasses, and polymers. Exact analytical soliton solutions are presented that describe self-trapped nonparaxial beams propagating at any angle with respect to the reference direction. These spatially symmetric solutions are, to the best of our knowledge, the first bistable Helmholtz solitons to be derived. Accompanying conservation laws (both integral and particular forms) are also reported. Numerical simulations investigate the stability of the solitons, which appear to be remarkably robust against perturbations

  8. The Coldest Cubic Meter in the Known Universe

    CERN Document Server

    Ouellet, Jonathan

    2014-01-01

    CUORE is a 741 kg array of TeO2 bolometers that will search for the neutrinoless double beta decay of 130Te. The detector is being constructed at the Laboratori Nazionali del Gran Sasso in Italy, where it will begin taking data in 2015. The CUORE cryostat will cool several metric tonnes of material to below 1 K and the CUORE detector itself will operate at a typical temperature of 10 mK. At this temperature, the CUORE detector will be the coldest contiguous cubic meter in the known Universe.

  9. Preparation of films of a highly aligned lipid cubic phase

    OpenAIRE

    Squires, Adam; Hallett, J.E.; Beddoes, C. M.; Plivelic, T. S.; Seddon, A. M.

    2013-01-01

    We demonstrate a method by which we can produce an oriented film of an inverse bicontinuous cubic phase (QII D) formed by the lipid monoolein (MO). By starting with the lipid as a disordered precursor (the L3 phase) in the presence of butanediol, we can obtain a film of the QII D phase showing a high degree of in-plane orientation by controlled dilution of the sample under shear within a linear flow cell. We demonstrate that the direction of orientation of the film is different from that foun...

  10. Transplant Center Search Form

    Science.gov (United States)

    ... Your Story Give Us Feedback - A + A Transplant Center Search Form Welcome to the Blood & Marrow Transplant ... centers for patients with a particular disease. Transplant Center login Username: * Password: * Request new password Join BMT ...

  11. Foreign bodies in the esophagus

    International Nuclear Information System (INIS)

    Foreign bodies (FB) in the esophagus (FBE) is one of the most frequent emergency consultations in the gastroenterology service and involves in its management specialties such as: surgery, otolaryngology and radiology. The type of foreign body and its incidence varies according to the geographical region and the age of the patients. there is controversy on the predictive value of the symptoms and the final finding of a foreign body. Likewise, the initial management protocol and the endoscopic intervention vary. Descriptive observational case-series study. Study performed from July 2004 to January 2006, patients more than one year of age were included in the study, with clinical suspicion of foreign body, attended at el Tunal hospital, be it because they consulted to this institution or because they wear referred from other centers belonging to the health district network, covering patient population of the socioeconomic layers 1 to 3. Suspicion of impaction less than seven days of evolution. Exclusion criteria. Patients less than one year old, and those not accepting to participate in the study. All of the patients were filled out a form including the target measurement variables. The objectives were as follows: 1. to determine the clinical useful parameters to predict if a foreign body is found during the higher digestive endoscopy. 2. Establish the frequency and location of the various foreign bodies. 3. Determine the efficacy of flexible endoscopy for extracting foreign bodies lodged in the esophagus. Results. 110 patients were included in the study, 50% of them male. Age span ranged from 1 to 79 o seven years old. 15% were less than 10 years old. In 60 of them a foreign body was found. The patients presented to the hospital 2 to 72 hours after initiation and upper gi tract endoscopy was performed within 12 hours after admission. The most frequent site of impaction was the upper esophagus, 58% (35/60), followed by the hypopharynx in 22% of cases (13/60). Fish

  12. Kennedy Space Center: Swamp Works

    Science.gov (United States)

    DeFilippo, Anthony Robert

    2013-01-01

    When I began my internship with the Granular Mechanics and Regolith Operations laboratory (GMRO), also known as Swamp Works, I was given the unique opportunity to shadow many teams working on various projects, and decide what projects I wanted to take part in. Before I go into details of my experiences at Swamp Works, I would like to take a moment to explain what I discovered Swamp Works to be. Swamp Works is a family of hardworking, dedicated, and driven people from various backgrounds and skill sets. These people all work to advance technologies and make science fiction science fact through means of rapid prototyping. They support and encourage failure as an option when learning new things, as long as lesson learned from said failure. In fact, their motto states "Fail, Fast, Forward." What this means is, not if but when one fails he or she must do so quickly and spring forward from the failure so that his or her progress is not delayed. With this acceptance, it provided me the confidence to dive into a multitude of projects working in various fields and with a wide range of skill sets. The first project I joined was Badger. My motivation for taking on this project was the opportunity I would have to obtain valuable experience working with 3D modeling and 3D printing technologies. Badger was a digging apparatus to be used in a highly dusty environment in a material known as Regolith. Regolith is a scientific term for the dirt or top soil found on planetary bodies. Regolith contains a large quantity of sediments less than lOppm and as a result poses a challenge of keeping it out of any cracks and crevices. Furthermore, regolith can create high levels of electrostatic energy, which can prove damaging to sensitive electrical hardware. With these characteristics in mind, I decided to take on the task of designing and manufacturing a dust proof cover for the sensitive electrical hardware. When I began this project, I did not have the slightest idea as to how to use 3D

  13. Uso de esteróides anabólicos androgênicos por praticantes de musculação de grandes academias da cidade de São Paulo Use of anabolic-androgenic steroids among body builders in major gym centers in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Luciana Silvia Maria Franco Silva

    2003-09-01

    Full Text Available O objetivo desta pesquisa foi estimar o consumo e traçar o perfil dos usuários de esteróides anabólicos androgênicos (EAA entre praticantes de musculação em três grandes academias de ginástica na cidade de São Paulo. Foi utilizado um questionário estruturado para ser respondido voluntária e anonimamente, com garantia explícita de confidencialidade para os mesmos. Os questionários ficaram disponíveis em três academias por uma semana, após ter sido feita ampla divulgação dos objetivos e importância do projeto. Responderam o questionário 209 praticantes de musculação (cerca de 3% do total. A incidência de uso de EAA foi de 19%, sendo que, destes, 8% declararam que fazem uso atualmente e 11%, que já haviam feito uso anteriormente; considerando apenas o sexo masculino, a incidência do uso foi de 24%. Os compostos mais utilizados foram estanozolol e decanoato de nandrolona. O perfil dos usuários pôde ser delineado: idade média de 27 anos (de 25 a 29 anos, predominantemente homens, motivação pela melhora na estética corporal e treinamento muscular intenso. Os EAA foram adquiridos, em sua maioria, em farmácias, sem receita médica e foram feitos uso de suplemento alimentar e outros fármacos em associação. Acreditam que os efeitos tóxicos/adversos podem ser controlados e/ou evitados com o uso de outros medicamentos e/ou acompanhamento médico. O presente trabalho mostra a necessidade de investigações mais abrangentes e aprofundadas, bem como a adoção de ações preventivas e educativas junto à população exposta aos EAA.To estimate the use of anabolic-androgenic steroids (AAS among body builders of three - professionally equipped private gym in São Paulo, Brazil, body builders answered voluntary and anonimously a structured multiple itens questionnaire which was available for a week in these gym centers. The participants were informed in advance of the aim of the study. Of the 209 body builders attending (3% of

  14. Lewy Body Disease

    Science.gov (United States)

    Lewy body disease is one of the most common causes of dementia in the elderly. Dementia is the loss of mental ... to affect normal activities and relationships. Lewy body disease happens when abnormal structures, called Lewy bodies, build ...

  15. Body Odor (For Girls)

    Science.gov (United States)

    ... Gynecology Medical Conditions Nutrition & Fitness Emotional Health Body Odor Posted under Health Guides . Updated 26 June 2015. + ... moisture, your body cools down. Where does body odor come from? When sweat mixes with the natural ...

  16. Body & Lifestyle Changes

    Science.gov (United States)

    ... Close X Home > Pregnancy > Body & lifestyle changes Body & lifestyle changes E-mail to a friend Please fill ... between pregnancies Nutrition, weight & fitness Prenatal care Body & lifestyle changes Is it safe? Labor & birth Postpartum care ...

  17. Inclusion Body Myositis

    Science.gov (United States)

    ... Awards Enhancing Diversity Find People About NINDS NINDS Inclusion Body Myositis Information Page Table of Contents (click ... and Information Additional resources from MedlinePlus What is Inclusion Body Myositis? Inclusion body myositis (IBM) is one ...

  18. Detergents Destabilize the Cubic Phase of Monoolein: Implications for Membrane Protein Crystallization

    OpenAIRE

    Misquitta, Y; Caffrey, M

    2003-01-01

    The in meso method for membrane protein crystallization uses a lipidic cubic phase as the hosting medium. The cubic phase provides a lipid bilayer into which the protein presumably reconstitutes and from which protein crystals nucleate and grow. The solutions used to spontaneously form the protein-enriched cubic phase often contain significant amounts of detergents that were employed initially to purify and to solubilize the membrane protein. By virtue of their surface activity, detergents ha...

  19. Womens Business Center

    Data.gov (United States)

    Small Business Administration — Women's Business Centers (WBCs) represent a national network of nearly 100 educational centers throughout the United States and its territories, which are designed...

  20. Engineering artificial signaling centers to polarize embryoid body differentiation

    DEFF Research Database (Denmark)

    Petersen, Dorthe R; Gustavsen, Carsten Richardt; Lindskog, Søren R; Magnuson, Mark A; Zaret, Kenneth S; Serup, Palle

    2012-01-01

    in ES cell aggregates. Fibroblasts engineered to express cadherins are assembled with ES cells to form composite aggregates where the fibroblasts are positioned as a discrete pole. When engineered to express secreted Wnt agonists or antagonists, this pole functions to localize signaling in a way that...

  1. Foreign body orbital cyst

    DEFF Research Database (Denmark)

    Yazdanfard, Younes; Heegard, Steffen; Fledelius, Hans C.;

    2001-01-01

    Ophthalmology, penetrating orbital injury, orbital foreign body, ultrasound, computed tomography (CT), histology......Ophthalmology, penetrating orbital injury, orbital foreign body, ultrasound, computed tomography (CT), histology...

  2. Electronic imaging of the human body.

    OpenAIRE

    Vannier, M. W.; Yates, R. E.; Whitestone, J.

    1992-01-01

    The Human Engineering Division of the Armstrong Laboratory (USAF); the Mallinckrodt Institute of Radiology; the Washington University School of Medicine; and the Lister-Hill National Center for Biomedical Communication, National Library of Medicine are sponsoring a working group on electronic imaging of the human body. Electronic imaging of the surface of the human body has been pursued and developed by a number of disciplines including radiology, forensics, surgery, engineering, medical educ...

  3. NONVERBAL STORIES: THE BODY IN PSYCHOTHERAPY

    Directory of Open Access Journals (Sweden)

    Richard G. Erskine

    2014-11-01

    Full Text Available Emotional experience is stored within the amygdala and the limbic system of the brain as affect, visceral, and physiological sensation without symbolization and language. These significant memories are expressed in affect and through our bodily movements and gestures. Such body memories are unconscious non-symbolized patterns of self-in-relationship. Several methods of a body centered psychotherapy are described and clinical case examples illustrate the use of expressive methods within a relational psychotherapy.

  4. Archimedes' floating bodies on a spherical Earth

    Science.gov (United States)

    Rorres, Chris

    2016-01-01

    Archimedes was the first to systematically find the centers of gravity of various solid bodies and to apply this concept in determining stable configurations of floating bodies. In this paper, we discuss an error in a proof developed by Archimedes that involves determining whether a uniform, spherical cap will float stably with its base horizontal in a liquid on a spherical Earth. We present a simpler, corrected proof and discuss aspects of his proof regarding a spherical cap that is not uniform.

  5. Radiation effects in nuclear ceramic oxides: cubic zirconia and pyrochlores

    International Nuclear Information System (INIS)

    Cubic (ZrO2-c) and pyrochlores with the Gd2(Ti1-xZrx)2O7 composition (O≤x≤1) are promising ceramic oxides for the immobilisation and/or transmutation of nuclear wastes. The aim of this thesis work is to test their radiation resistance in a harsh radiative environment. Both materials were irradiated with low (a few MeV) and high (hundred MeV) energy ions in order to study the damage resulting from ballistic collisions and electronic excitations. The radiations induced modifications were analyzed by combining several advanced techniques: Rutherford Backscattering Spectrometry (RBS/C), X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). It was found that cubic zirconia is particularly resistant against irradiation whereas phase transformations were observed in pyrochlores depending on their composition. In ZrO2-c, the damage accumulation follows a three-step process: dislocation loops overlap to form a network of long dislocations acting as defect sinks. At high energy, the damage cumulates in a one step process and occurs through the creation and the overlapping of ion tracks; dislocations are formed along the ion trajectories. Phase transformations are observed in the Gd2(Ti1-xZrx)2 O7 system independently of the ion energy: Gd2Ti2O7 and Gd2TiZrO7 are amorphized, whereas Gd2Zr2O7 is transformed in a defective fluorite-type structure. (author)

  6. Defect ordering in aliovalently doped cubic zirconia from first principles

    International Nuclear Information System (INIS)

    Defect ordering in aliovalently doped cubic-stabilized zirconia is studied using gradient corrected density-functional calculations. Intra- and intersublattice ordering interactions are investigated for both cation (Zr and dopant ions) and anion (oxygen ions and vacancies) species. For yttria-stabilized zirconia, the crystal structure of the experimentally identified, ordered compound δ-Zr3Y4O12 is established, and we predict metastable zirconia-rich ordered phases. Anion vacancies repel each other at short separations, but show an energetic tendency to align as third-nearest neighbors along directions. Calculations with divalent (Be, Mg, Ca, Sr, Ba) and trivalent (Y, Sc, B, Al, Ga, In) oxides show that anion vacancies prefer to be close to the smaller of the cations (Zr or dopant ion). When the dopant cation is close in size to Zr, the vacancies show no particular preference, and are thus less prone to be bound preferentially to any particular cation type when the vacancies traverse such oxides. This ordering tendency offers insight into the observed high conductivity of Y2O3- and Sc2O3-stabilized zirconia, as well as recent results using, e.g., lanthanide oxides. The calculations point to In2O3 as a particularly promising stabilizer for high ionic conductivity. Thus we are able to directly link (thermodynamic) defect ordering to (kinetic) ionic conductivity in cubic-stabilized zirconia using first-principles atomistic calculations

  7. Elastic interaction of point defects in cubic and hexagonal crystals

    Science.gov (United States)

    Kukushkin, S. A.; Osipov, A. V.; Telyatnik, R. S.

    2016-05-01

    The elastic interaction of two point defects in cubic and hexagonal structures has been considered. On the basis of the exact expression for the tensor Green's function of the elastic field obtained by the Lifschitz-Rozentsveig for a hexagonal medium, an exact formula for the interaction energy of two point defects has been obtained. The solution is represented as a function of the angle of their relative position on the example of semiconductors such as III-nitrides and α-SiC. For the cubic medium, the solution is found on the basis of the Lifschitz-Rozentsveig Green's tensors corrected by Ostapchuk, in the weak-anisotropy approximation. It is proven that the calculation of the interaction energy by the original Lifschitz-Rozentsveig Green's tensor leads to the opposite sign of the energy. On the example of the silicon crystal, the approximate solution is compared with the numerical solution, which is represented as an approximation by a series of spherical harmonics. The range of applicability of the continual approach is estimated by the quantum mechanical calculation of the lattice Green's function.

  8. A family of quasi-cubic blended splines and applications

    Institute of Scientific and Technical Information of China (English)

    SU Ben-yue; TAN Jie-qing

    2006-01-01

    A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter α, defined by the introduced base functions, include the B-spline curves and can approximate the B-spline curves from both sides. The curves can be adjusted easily by using the shape parameter α, where dpi(α,t) is linear with respect to dα for the fixed t. With the shape parameter chosen properly,the defined curves can be used to precisely represent straight line segments, parabola segments, circular arcs and some transcendental curves, and the corresponding tensor product surfaces can also represent spherical surfaces, cylindrical surfaces and some transcendental surfaces exactly. By abandoning positive property, this paper proposes a new C2 continuous blended interpolation spline based on piecewise trigonometric polynomials associated with a sequence of local parameters. Illustration showed that the curves and surfaces constructed by the blended spline can be adjusted easily and freely. The blended interpolation spline curves can be shape-preserving with proper local parameters since these local parameters can be considered to be the magnification ratio to the length of tangent vectors at the interpolating points. The idea is extended to produce blended spline surfaces.

  9. Nano-Engineered Cubic Zirconia for Orthopaedic Implant Applications

    Science.gov (United States)

    Namavar, F.; Rubinstein, A.; Sabirianov, R.; Thiele, G.; Sharp, J.; Pokharel, U.; Namavar, R.; Garvin, K.

    2012-02-01

    Osseointegration failure of the prosthesis prevents long-term stability, which contributes to pain, implant loosening, and infection that usually necessitates revision surgery. Cell attachment and spreading in vitro is generally mediated by adhesive proteins such as fibronectin and vitronectin. We designed and produced pure cubic zirconia (ZrO2) ceramic coatings by ion beam assisted deposition (IBAD) with nanostructures comparable to the size of proteins. Our ceramic coatings exhibit high hardness and a zero contact angle with serum. In contrast to Hydroxyapatite (HA), nano-engineered zirconia films possess excellent adhesion to all orthopaedic materials. Adhesion and proliferation experiments were performed with a bona fide mesenchymal stromal cells cell line (OMA-AD). Our experimental results indicated that nano-engineered cubic zirconia is superior in supporting growth, adhesion, and proliferation. We performed a comparative analysis of adsorption energies of the FN fragment using quantum mechanical calculations and Monte Carlo simulation on both types of surfaces: smooth and nanostructured. We have found that the initial FN fragment adsorbs significantly stronger on the nanostructured surface than on the smooth surface.

  10. Precursor design of vapour deposited cubic boron nitride versus diamond

    International Nuclear Information System (INIS)

    The similarities and dissimilarities in the growth of diamond vs. cubic boron nitride (c-BN) were studied using quantum mechanical calculations. Great similarities were observed when considering the surface stabilization by H atoms. Very great similarities were recorded when considering the adsorption of various growth species to these materials. It was found necessary to avoid mixtures of B- and N-containing species in the gas phase during c-BN growth, since they should most probably result in a mixture of these species also on the surfaces. Greater dissimilarities were observed when studying the surface migrations on the diamond and c-BN surfaces and nucleation of the cubic phases on the corresponding hexagonal ones. Nucleation of diamond/c-BN on graphite/h-BN was found to be energetically feasible. This was calculated to be especially the situation for the armchair edge of the basal plane of h-BN and of the zigzag edge of the basal plane of graphite. These theoretical results can be used as guidelines in the strive towards thin film deposition of c-BN using gentle chemical vapour deposition methods like atomic layer deposition. (author)

  11. Reversible Nanoparticle Cubic Lattices in Blue Phase Liquid Crystals.

    Science.gov (United States)

    Gharbi, Mohamed Amine; Manet, Sabine; Lhermitte, Julien; Brown, Sarah; Milette, Jonathan; Toader, Violeta; Sutton, Mark; Reven, Linda

    2016-03-22

    Blue phases (BPs), a distinct class of liquid crystals (LCs) with 3D periodic ordering of double twist cylinders involving orthogonal helical director twists, have been theoretically studied as potential templates for tunable colloidal crystals. Here, we report the spontaneous formation of thermally reversible, cubic crystal nanoparticle (NP) assemblies in BPs. Gold NPs, functionalized to be highly miscible in cyanobiphenyl-based LCs, were dispersed in BP mixtures and characterized by polarized optical microscopy and synchrotron small-angle X-ray scattering (SAXS). The NPs assemble by selectively migrating to periodic strong trapping sites in the BP disclination lines. The NP lattice, remarkably robust given the small particle size (4.5 nm diameter), is commensurate with that of the BP matrix. At the BP I to BP II phase transition, the NP lattice reversibly switches between two different cubic structures. The simultaneous presence of two different symmetries in a single material presents an interesting opportunity to develop novel dynamic optical materials. PMID:26900753

  12. Spinel type twins of the new cubic Er{sub 6}Zn{sub 23}Ge compound

    Energy Technology Data Exchange (ETDEWEB)

    Solokha, Pavlo; De Negri, Serena; Saccone, Adriana [Genova Univ. (Italy). Dipt. di Chimica e Chimica Industriale; Proserpio, Davide M. [Univ. degli Studi di Milano (Italy). Dipt. di Chimica; Samara State Univ. (Russian Federation). Samara Center for Theoretical Materials Science (SCTMS)

    2016-04-01

    The crystal structure of the new Er{sub 6}Zn{sub 23}Ge intermetallic compound was established by X-ray diffraction analysis on a twinned crystal (space group Fm anti 3m, Wyckoff sequence: f{sup 2}edba, cF120-Zr{sub 6}Zn{sub 23}Si, a=12.7726(6) Aa). The crystal is composed of two nearly equal size domains, whose mutual orientation is described by a 180 rotation around the cubic [111] axis, i.e. a spinel-type twinning law, not common for intermetallics. Applying the nanocluster approach, Er{sub 6}Ge octahedra and centered two-shell Zn{sub 45} clusters were found as structural building blocks, filling the crystal space in a NaCl-like arrangement. This description was adopted to interpret the twinning in terms of stacking faults in the fcc cubic close packed arrangement. Moreover, the assembly of the nanocluster units is proposed as a possible mechanism for crystal growth and twin formation, in agreement with the principle of the interface energy minimization. Experimental conditions such as supersaturation and co-formation of other phases are also considered as favorable factors for Er{sub 6}Zn{sub 23}Ge twin formation.

  13. Student Success Center Toolkit

    Science.gov (United States)

    Jobs For the Future, 2014

    2014-01-01

    "Student Success Center Toolkit" is a compilation of materials organized to assist Student Success Center directors as they staff, launch, operate, and sustain Centers. The toolkit features materials created and used by existing Centers, such as staffing and budgeting templates, launch materials, sample meeting agendas, and fundraising…

  14. Body Matters: Narratives of the Body

    OpenAIRE

    Asandi, Iren; Filipovska, Kalina; Neault, Megan; Olsen, Sara Høier

    2014-01-01

    This project engages the notion of the subjective body in a pasture of social constructions in order to gather an understanding of the narratives created by women about their bodies in relation to cosmetic surgery. The empirical data for this project comes from our virtual ethnographic research on the various forums from the MyLooks website. Moreover, perspectives regarding the body, beauty ideals and theoretical positions from Kathryn Morgan and Kathy Davis fill out the structure of the proj...

  15. Determination of Star Bodies from -Centroid Bodies

    Indian Academy of Sciences (India)

    Lujun Guo; Gangsong Leng

    2013-11-01

    In this paper, we prove that an origin-symmetric star body is uniquely determined by its -centroid body. Furthermore, using spherical harmonics, we establish a result for non-symmetric star bodies. As an application, we show that there is a unique member of $_p\\langle K \\rangle$ characterized by having larger volume than any other member, for all real ≥ 1 that are not even natural numbers, where $_p\\langle K \\rangle$ denotes the -centroid equivalence class of the star body .

  16. Media and Body Image

    Science.gov (United States)

    ... Management Education & Events Advocacy For Patients About ACOG Media and Body Image Home For Patients Search FAQs Media and Body ... and Body Image TFAQ002, June 2016 PDF Format Media and Body Image Especially For Teens How can the media make ...

  17. Reinforced Airfoil Shaped Body

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to an airfoil shaped body with a leading edge and a trailing edge extending along the longitudinal extension of the body and defining a profile chord, the airfoil shaped body comprising an airfoil shaped facing that forms the outer surface of the airfoil shaped body...

  18. Adolescence and Body Image.

    Science.gov (United States)

    Weinshenker, Naomi

    2002-01-01

    Discusses body image among adolescents, explaining that today's adolescents are more prone to body image distortions and dissatisfaction than ever and examining the historical context; how self-image develops; normative discontent; body image distortions; body dysmorphic disorder (BDD); vulnerability of boys (muscle dysmorphia); who is at risk;…

  19. Cubical Mass-Spring Model design based on a tensile deformation test and nonlinear material model.

    Science.gov (United States)

    San-Vicente, Gaizka; Aguinaga, Iker; Tomás Celigüeta, Juan

    2012-02-01

    Mass-Spring Models (MSMs) are used to simulate the mechanical behavior of deformable bodies such as soft tissues in medical applications. Although they are fast to compute, they lack accuracy and their design remains still a great challenge. The major difficulties in building realistic MSMs lie on the spring stiffness estimation and the topology identification. In this work, the mechanical behavior of MSMs under tensile loads is analyzed before studying the spring stiffness estimation. In particular, the performed qualitative and quantitative analysis of the behavior of cubical MSMs shows that they have a nonlinear response similar to hyperelastic material models. According to this behavior, a new method for spring stiffness estimation valid for linear and nonlinear material models is proposed. This method adjusts the stress-strain and compressibility curves to a given reference behavior. The accuracy of the MSMs designed with this method is tested taking as reference some soft-tissue simulations based on nonlinear Finite Element Method (FEM). The obtained results show that MSMs can be designed to realistically model the behavior of hyperelastic materials such as soft tissues and can become an interesting alternative to other approaches such as nonlinear FEM. PMID:22156291

  20. Numerical solution of the 1D kinetics equations using a cubic reduced nodal scheme

    International Nuclear Information System (INIS)

    In this work a finite differences technique centered in mesh based on a cubic reduced nodal scheme type finite element to solve the equations of the kinetics 1 D that include the equations corresponding to the concentrations of precursors of delayed neutrons is described. The technique of finite elements used is that of Galerkin where so much the neutron flux as the concentrations of precursors its are spatially approached by means of a three grade polynomial. The matrices of rigidity and of mass that arise during this discretization process are numerically evaluated using the open quadrature non standard of Newton-Cotes and that of Radau respectively. The purpose of the application of these quadratures is the one of to eliminate in the global matrices the couplings among the values of the flow in points of the discretization with the consequent advantages as for the reduction of the order of the matrix associated to the discreet problem that is to solve. As for the time dependent part the classical integration scheme known as Θ scheme is applied. After carrying out the one reordering of unknown and equations it arrives to a reduced system that it can be solved but quickly. With the McKin compute program developed its were solved three benchmark problems and those results are shown for the relative powers. (Author)

  1. Management of nuclear training center

    International Nuclear Information System (INIS)

    This report describes the annual results of training courses. The scope and contents are as follows : 1. Regional and interregional training courses, 2. Training courses assisted by foreign experts, 3. Training courses for nuclear industry personnel, 4. Training courses for internal staff-members, 5. Training courses under the law. The nuclear training center executed the open-door training courses for 2,699 engineers/scientists from the regulatory body, nuclear industries, research institutes and other related organizations by means of offering 69 training courses during the fiscal year 1995. (Author) .new

  2. Comparative Study between Cubic and non-Cubic Equations of State Using Carnahan-Starling Repulsive Term: Application of Temperature-Dependent Alpha and Beta Functions

    OpenAIRE

    Checoni, Ricardo Figueiredo; Aznar, Martin

    2014-01-01

    Studies on phase equilibria data behavior of pure substances are motivation to the researchers due to importance of these data for the scientific and industrial applications. Several EOS were proposed and its modifications have been made, whose aim is to improve the correlation between experimental and calculated thermophysical properties. This work proposes a comparative study between the PVT calculated data using cubic and non-cubic equations of state, in which its original repulsive term i...

  3. General -Harmonic Blaschke Bodies

    Indian Academy of Sciences (India)

    Yibin Feng; Weidong Wang

    2014-02-01

    Lutwak introduced the harmonic Blaschke combination and the harmonic Blaschke body of a star body. Further, Feng and Wang introduced the concept of the -harmonic Blaschke body of a star body. In this paper, we define the notion of general -harmonic Blaschke bodies and establish some of its properties. In particular, we obtain the extreme values concerning the volume and the -dual geominimal surface area of this new notion.

  4. Effect of Phospholipids and a Transmembrane Peptide on the Stability of the Cubic Phase of Monoolein: Implication for Protein Crystalization from a Cubic Phase

    Science.gov (United States)

    Chupin, V.; Killian, J. A.; de Kruijff, B.

    2003-01-01

    The cubic phase of monoolein has successfully been used for crystallization of a number of membrane proteins. However, the mechanism of protein crystallization in the cubic phase is still unknown. It was hypothesized, that crystallization occurs at locally formed patches of bilayers. To get insight into the stability of the cubic phase, we investigated the effect of different phospholipids and a model transmembrane peptide on the lipid organization in mixed monoolein systems. Deuterium-labeled 1-oleoyl-rac-[2H5]-glycerol was used as a selective probe for 2H NMR. The phase behavior of the phospholipids was followed by 31P NMR. Upon incorporation of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, or phosphatidic acid, the cubic phase of monoolein transformed into the Lα or HII phase depending on the phase preference of the phospholipid and its concentration. The ability of phospholipids to destabilize the cubic phase was found to be dependent on the phospholipid packing properties. Electrostatic repulsion facilitated the cubic-to-Lα transition. Incorporation of the transmembrane peptide KALP31 induced formation of the Lα phase with tightly packed lipid molecules. In all cases when phase separation occurs, monoolein and phospholipid participate in both phases. The implications of these findings for protein crystallization are discussed. PMID:12668446

  5. On the number of longest and almost longest cycles in cubic graphs

    DEFF Research Database (Denmark)

    Chia, Gek Ling; Thomassen, Carsten

    2012-01-01

    We consider the questions: How many longest cycles must a cubic graph have, and how many may it have? For each k >= 2 there are infinitely many p such that there is a cubic graph with p vertices and precisely one longest cycle of length p-k. On the other hand, if G is a graph with p vertices, all...

  6. Energy decay for Maxwell's equations with Ohm's law in partially cubic domains

    OpenAIRE

    Phung, Kim Dang

    2013-01-01

    We prove a polynomial energy decay for the Maxwell's equations with Ohm's law in partially cubic domains with trapped rays. We extend the results of polynomial decay for the scalar damped wave equation in partially rectangular or cubic domain. Our approach have some similitude with the construction of reflected gaussian beams.

  7. Non-spherical micelles in an oil-in-water cubic phase

    DEFF Research Database (Denmark)

    Leaver, M.; Rajagopalan, V.; Ulf, O.;

    2000-01-01

    The cubic phase formed between the microemulsion and hexagonal phases of the ternary pentaethylene glycol dodecyl ether (C12E5)-decane-water system and that doped with small amounts of sodium dodecylsulfate (SDS) have been investigated. The presence of discrete oil-swollen micelles in the cubic...

  8. Cubic Plus Association Equation of State for Flow Assurance Projects

    DEFF Research Database (Denmark)

    dos Santos, Leticia Cotia; Abunahman, Samir Silva; Tavares, Frederico Wanderley;

    2015-01-01

    Thermodynamic hydrate inhibitors such as methanol, ethanol, (mono) ethylene glycol (MEG), and triethylene glycol (TEG) are widely used in the oil and gas industry. On modeling these compounds, we show here how the CPA equation of state was implemented in an in-house process simulator as an in......-built model: To validate the implementation, we show calulations for binary systems containing hydrate inhibitors and water or hydrocarbons using the Cubic Plus Association (CPA) and Soave-Redlich-Kwong (SRK) equation of states, also comparing against experimental data. For streams containing natural gas and...... packages for glycol applications, proving that the CPA calculations are in good agreement with these models and showing that this is an adequate way to simulate complex matures containing natural gas, water, and hydrate inhibitors....

  9. Optical Absorption on Cubicβ-PbF2 Crystals

    Institute of Scientific and Technical Information of China (English)

    任国浩; 沈定中; 王绍华; 殷之文

    2001-01-01

    The transmission spectra of cubic β-PbF2 crystals grown by the non-vacuum Bridgman method were measured with a spectrophotometer. It was found that there are several optical absorption bands peaking at 300nm,390-400nm, as well as at 460nm. According to composition analysis, doping and annealing experiments, it is suggested that the absorption at 300nm originates from the electron transition of Ce ions from 4f → 5d. The absorption at 390-400nm may result from the colour centres related to oxygen impurities. In addition, the sample recrystallized from the coloured β-PbF2 crystal exhibits a new absorption band at 460 nm, which might be caused by trace lead vacancies.

  10. Two-dimensional hysteresis properties of cubic silicon steel

    International Nuclear Information System (INIS)

    Cubic silicon steel has (100) crystallographic plane on its surface and two magnetic easy axes in (100) plane are processed to coincide to two perpendicular axis. This feature prompts the use of this material under the rotational magnetic field compared to the conventional grain oriented silicon steel which shows extraordinary increase of iron loss in the off easy axis direction. Aiming this practical use, the two dimensional magnetic properties are measured under the various conditions, and the magnetization properties and loss characteristics became clear. The magnetizing properties between flux density B and magnetizing field H are represented numerically by E and S modeling. ne small amount of the hysteresis properties under the alternating flux condition and rotational flux condition are well represented by E and S model. (Author)

  11. Antiferromagnetic resonance in the cubic perovskite KNiF3

    Science.gov (United States)

    Yamaguchi, H.; Katsumata, K.; Hagiwara, M.; Tokunaga, M.; Liu, H. L.; Zibold, A.; Tanner, D. B.; Wang, Y. J.

    1999-03-01

    Low-temperature high-magnetic-field far-infrared spectroscopy and electron-spin-resonance measurements have been performed on single crystals of the cubic perovskite KNiF3. We found the absorption at 48.7+/-0.3 cm-1 observed by Richards [P. L. Richards, J. Appl. Phys. 34, 1237 (1963)] that was attributed to antiferromagnetic resonance (AFMR) is not magnetic in origin. Instead, a different absorption is well fit by a theory of AFMR with uniaxial anisotropy. Analysis yields an anisotropy energy of 8.7×10-3 cm-1. The ratio between the anisotropy field and the exchange field is 2.4×10-5. Thus, KNiF3 is an excellent example of a Heisenberg antiferromagnet.

  12. Cubic Derivative Interactions and Asymptotic Dynamics of the Galileon Vacuum

    CERN Document Server

    De Arcia, Roberto; León, Genly; Nucamendi, Ulises; Quiros, Israel

    2015-01-01

    In this paper we apply the tools of the dynamical systems theory in order to uncover the whole asymptotic structure of the vacuum interactions of a galileon model with a cubic derivative interaction term. It is shown that, contrary to what occurs in the presence of background matter, the galileon interactions of vacuum appreciably modify the late-time cosmic dynamics. In particular, a local late-time attractor representing phantom behavior arises which is inevitably associated with a big rip singularity. It seems that the gravitational interactions of the background matter with the galileon screen the effects of the gravitational self-interactions of the galileon, thus erasing any potential modification of the late-time dynamics by the galileon vacuum processes. Unlike other galileon models inspired in the DGP scenario, self-accelerating solutions do not arise in this model.

  13. Experimental core electron density of cubic boron nitride

    DEFF Research Database (Denmark)

    Wahlberg, Nanna; Bindzus, Niels; Bjerg, Lasse;

    boron nitride we may obtain a deeper understanding of the effect of bonding on the total density. We report here a thorough investigation of the charge density of cubic boron nitride with a detailed modelling of the inner atom charge density. By combining high resolution powder X-ray diffraction data...... has been obtained. The displacement parameters reported here are significantly lower than those previously reported, stressing the importance of an adequate description of the core density. The charge transfer from boron to nitrogen clearly affects the inner electron density, which is evident from...... theoretical as well as experimental result. The redistribution of electron density will, if not accounted for, result in increased thermal parameters. It is estimated that 1.7-2 electrons is transferred from boron to nitrogen. [1]: N. Bindzus, T. Straasø, N. Wahlberg, J. Becker, L. Bjerg, N. Lock, A...

  14. Adaptive image coding based on cubic-spline interpolation

    Science.gov (United States)

    Jiang, Jian-Xing; Hong, Shao-Hua; Lin, Tsung-Ching; Wang, Lin; Truong, Trieu-Kien

    2014-09-01

    It has been investigated that at low bit rates, downsampling prior to coding and upsampling after decoding can achieve better compression performance than standard coding algorithms, e.g., JPEG and H. 264/AVC. However, at high bit rates, the sampling-based schemes generate more distortion. Additionally, the maximum bit rate for the sampling-based scheme to outperform the standard algorithm is image-dependent. In this paper, a practical adaptive image coding algorithm based on the cubic-spline interpolation (CSI) is proposed. This proposed algorithm adaptively selects the image coding method from CSI-based modified JPEG and standard JPEG under a given target bit rate utilizing the so called ρ-domain analysis. The experimental results indicate that compared with the standard JPEG, the proposed algorithm can show better performance at low bit rates and maintain the same performance at high bit rates.

  15. Equidistribution of values of linear forms on a cubic hypersurface

    OpenAIRE

    Chow, Sam

    2016-01-01

    Let C be a cubic form with integer coefficients in n variables, and let h be the h-invariant of C. Let L1,…,Lr be linear forms with real coefficients such that, if α∈ℝr∖{0}, then α⋅L is not a rational form. Assume that h>16+8r. Let τ∈ℝr, and let η be a positive real number. We prove an asymptotic formula for the weighted number of integer solutions x∈[−P,P]n to the system C(x)=0, |L(x)−τ|<η. If the coefficients of the linear forms are algebraically independent over the rationals, then w...

  16. Quantum-Carnot engine for particle confined to cubic potential

    Energy Technology Data Exchange (ETDEWEB)

    Sutantyo, Trengginas Eka P., E-mail: trengginas.eka@gmail.com; Belfaqih, Idrus H., E-mail: idrushusin21@gmail.com; Prayitno, T. B., E-mail: teguh-budi@unj.ac.id [Department of Physics, State University of Jakarta, Jl. Pemuda No.10, Rawamangun, Jakarta Timur 13220 (Indonesia)

    2015-09-30

    Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system.

  17. Submicron cubic boron nitride as hard as diamond

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guoduan; Kou, Zili, E-mail: kouzili@scu.edu.cn, E-mail: yanxz@hpstar.ac.cn; Lei, Li; Peng, Fang; Wang, Qiming; Wang, Kaixue; Wang, Pei; Li, Liang; Li, Yong; Wang, Yonghua [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Yan, Xiaozhi, E-mail: kouzili@scu.edu.cn, E-mail: yanxz@hpstar.ac.cn; Li, Wentao [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China); Bi, Yan [Institute of Fluid Physics and National Key Laboratory of Shockwave and Detonation Physic, China Academy of Engineering Physics, Mianyang 621900 (China); Leng, Yang [Department of Mechanical Engineering, Hong Kong University of Science and Technology, Kowloon, Hong Kong (China); He, Duanwei [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Institute of Fluid Physics and National Key Laboratory of Shockwave and Detonation Physic, China Academy of Engineering Physics, Mianyang 621900 (China)

    2015-03-23

    Here, we report the sintering of aggregated submicron cubic boron nitride (sm-cBN) at a pressure of 8 GPa. The sintered cBN compacts exhibit hardness values comparable to that of single crystal diamond, fracture toughness about 5-fold that of cBN single crystal, in combination with a high oxidization temperature. Thus, another way has been demonstrated to improve the mechanical properties of cBN besides reducing the grain size to nano scale. In contrast to other ultrahard compacts with similar hardness, the sm-cBN aggregates are better placed for potential industrial application, as their relative low pressure manufacturing perhaps be easier and cheaper.

  18. Inverse cubic law of index fluctuation distribution in Indian markets

    CERN Document Server

    Pan, R K; Pan, Raj Kumar; Sinha, Sitabhra

    2006-01-01

    One of the principal statistical features characterizing the activity in financial markets is the distribution of fluctuations in market indicators such as the index. While the developed stock markets such as the New York Stock Exchange (NYSE) have been found to show heavy-tailed fluctuation distribution, there have been claims that emerging markets behave differently. Here we investigate the distribution of several indices from the Indian financial market, one of the largest emerging markets in the world. We have used both tick-by-tick data from the National Stock Exchange (NSE) and daily closing data from both NSE and Bombay Stock Exchange (BSE). We find that the cumulative distribution of index fluctuations has long tails consistent with a power law having exponent $\\alpha \\approx 3$, independent of the time-scale of observation or the market index used for the analysis. This ``inverse cubic law'' is quantitatively similar to what has been observed in developed markets, thereby providing strong evidence th...

  19. THERMODYNAMIC PARAMETERS OF LEAD SULFIDE CRYSTALS IN THE CUBIC PHASE

    Directory of Open Access Journals (Sweden)

    T. O. Parashchuk

    2016-07-01

    Full Text Available Geometric and thermodynamic parameters of cubic PbS crystals were obtained using the computer calculations of the thermodynamic parameters within density functional theory method DFT. Cluster models for the calculation based on the analysis of the crystal and electronic structure. Temperature dependence of energy ΔE and enthalpy ΔH, Gibbs free energy ΔG, heat capacity at constant pressure CP and constant volume CV, entropy ΔS were determined on the basis of ab initio calculations of the crystal structure of molecular clusters. Analytical expressions of temperature dependences of thermodynamic parameters which were approximated with quantum-chemical calculation points have been presented. Experimental results compared with theoretically calculated data.

  20. Quantum-Carnot engine for particle confined to cubic potential

    International Nuclear Information System (INIS)

    Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system

  1. Low temperature synthesis and photoluminescence of cubic silicon carbide

    International Nuclear Information System (INIS)

    Cubic silicon carbide (3C-SiC) powder was synthesized at 460 deg. C in the ScCO2-metallic Na system, using cheap industrial FeSiδ alloy (≤500 mesh) and CO2, as silicon and carbon sources, respectively. The products were characterized by x-ray diffraction and Raman spectrum analysis. The results show that increasing the heating-up rate, adding a metallic sodium dose and prolonging the heating time favour the formation of 3C-SiC. A very strong photoluminescence band peaking at 436 nm was observed, showing a blue shift compared with the blue-green luminescence from films of 3C-SiC. A possible mechanism behind the blue shift is discussed

  2. Implicit CIP (Cubic-Interpolated Propagation) method in one dimension

    International Nuclear Information System (INIS)

    A new implicit numerical solver for hyperbolic equations is proposed. This method is based on the CIP (Cubic-Interpolated Propagation) method that was proposed in an explicit form. Both a physical quantity and its spatial derivative are determined so as to obey the given equation. Just same as the CIP method, this method provides a stable and less diffusive result although it has an implicit form. Most importantly, this method, like other implicit schemes, is stable even in a high-CFL computation. In addition, this scheme can be directly solved by non-iterative procedure because of the two-points connected systems although it has third-order accuracy. The scheme is applied to a one-dimensional shock-tube problem accompanied by a region expanding with quite a high velocity. (author)

  3. Preparation of ohmic n-type cubic boron nitride contacts

    CERN Document Server

    Wang Cheng Xin; Li Xun; Zhang Tie Chen; Han Yong; Luo Ji Feng; Shen Cai Xia; Gao Chun Xi; Zou Guang Tian

    2002-01-01

    Ohmic electrodes in the form of n-type (Si-doped) cubic boron nitride (c-BN) bulk crystals were fabricated by utilizing a covering technique, depositing Ti(10 nm)/Mo/(20 nm)/Pt-Au(200 nm) ohmic contact metal on both the sides of the c-BN substrate. The size of the specimen electrode was 100 x 100 mu m sup 2 on one side and 300 x 300 mu m sup 2 on the other side. Measurements on the specimen were made using a specially made device. Linear current-voltage characteristics were obtained. It is considered that the contact between the Ti-and Si-doped c-BN was ohmic.

  4. Enhanced initial protein adsorption on an engineered nanostructured cubic zirconia

    CERN Document Server

    Sabirianov, R F; Namavar, F

    2010-01-01

    Motivated by experimentally observed biocompatibility enhancement of nanoengineered cubic zirconia ZrO2 coatings to mesenchymal stromal cells, we have carried out computational analysis of the initial immobilization of one of known structural fragment of the adhesive protein (fibronectin) on the corresponding surface. We constructed an atomistic model of the zirconia nano-hillock of 3-fold symmetry based on AFM and TEM images. First-principle quantum-mechanical calculations show a substantial variation of electrostatic potential at the hillock due to the presence of surface features such as edges and vertexes. Using an implemented Monte Carlo simulated annealing method we found the orientation of the immobilized protein on the zirconia surface (both flat and nanostructured) and contribution of the each amino acid residue from the protein sequence to the adsorption energy. Accounting for the variation of the dielectric permittivity at the protein-implant interface we use a model distance-dependent dielectric f...

  5. Energy Density Bounds in Cubic Quasi-Topological Cosmology

    CERN Document Server

    dS, U Camara; Sotkov, G M

    2013-01-01

    We investigate the thermodynamical and causal consistency of cosmological models of the cubic Quasi-Topological Gravity (QTG) in four dimensions, as well as their phenomenological consequences. Specific restrictions on the maximal values of the matter densities are derived by requiring the apparent horizon's entropy to be a non-negative, non-decreasing function of time. The QTG counterpart of the Einstein-Hilbert (EH) gravity model of linear equation of state is studied in detail. An important feature of this particular QTG cosmological model is the new early-time acceleration period of the evolution of the Universe, together with the standard late-time acceleration present in the original EH model. The QTG correction to the causal diamond's volume is also calculated.

  6. Plasmon polaritons in cubic lattices of spherical metallic nanoparticles

    CERN Document Server

    Lamowski, Simon; Mariani, Eros; Weick, Guillaume; Pauly, Fabian

    2016-01-01

    We investigate theoretically plasmon polaritons in cubic lattices of interacting spherical metallic nanoparticles. Dipolar localized surface plasmons on each nanoparticle couple through the near field dipole-dipole interaction and form collective plasmons which extend over the whole metamaterial. Coupling these collective plasmons in turn to photons leads to plasmon polaritons. We derive within a quantum model general semi-analytical expressions to evaluate both plasmon and plasmon-polariton dispersions that fully account for nonlocal effects in the dielectric function of the metamaterial. Within this model, we discuss the influence of different lattice symmetries and predict related polaritonic gaps within the near-infrared to the visible range of the spectrum that depend on wavevector direction and polarization.

  7. Bistable dark solitons of a cubic-quintic Helmholtz equation

    International Nuclear Information System (INIS)

    We provide a report on exact analytical bistable dark spatial solitons of a nonlinear Helmholtz equation with a cubic-quintic refractive-index model. Our analysis begins with an investigation of the modulational instability characteristics of Helmholtz plane waves. We then derive a dark soliton by mapping the desired asymptotic form onto a uniform background field and obtain a more general solution by deploying rotational invariance laws in the laboratory frame. The geometry of the new soliton is explored in detail, and a range of new physical predictions is uncovered. Particular attention is paid to the unified phenomena of arbitrary-angle off-axis propagation and nondegenerate bistability. Crucially, the corresponding solution of paraxial theory emerges in a simultaneous multiple limit. We conclude with a set of computer simulations that examine the role of Helmholtz dark solitons as robust attractors.

  8. Spatial 't Hooft loop to cubic order in hot QCD

    CERN Document Server

    Giovannangeli, P

    2002-01-01

    Spatial 't Hooft loops of strength k measure the qualitative change in the behaviour of electric colour flux in confined and deconfined phase of SU (N) gauge theory. They show an area law in the deconfined phase, known analytica lly to two loop order with a ``k-scaling'' law k(N-k). In this paper we comput e the O(g^3) correction to the tension. It is due to neutral gluon fields that get their mass through interaction with the wall. The simple k-scaling is lost in cubic order. The generic problem of non-convexity shows up in this order an d the cure is provided. The result for large N is explicitely given. We show tha t nonperturbative effects appear at O(g^5).

  9. Perbaikan Metode Penghitungan Debit Sungai Menggunakan Cubic Spline Interpolation

    Directory of Open Access Journals (Sweden)

    Budi I. Setiawan

    2007-09-01

    Full Text Available Makalah ini menyajikan perbaikan metode pengukuran debit sungai menggunakan fungsi cubic spline interpolation. Fungi ini digunakan untuk menggambarkan profil sungai secara kontinyu yang terbentuk atas hasil pengukuran jarak dan kedalaman sungai. Dengan metoda baru ini, luas dan perimeter sungai lebih mudah, cepat dan tepat dihitung. Demikian pula, fungsi kebalikannnya (inverse function tersedia menggunakan metode. Newton-Raphson sehingga memudahkan dalam perhitungan luas dan perimeter bila tinggi air sungai diketahui. Metode baru ini dapat langsung menghitung debit sungaimenggunakan formula Manning, dan menghasilkan kurva debit (rating curve. Dalam makalah ini dikemukaan satu canton pengukuran debit sungai Rudeng Aceh. Sungai ini mempunyai lebar sekitar 120 m dan kedalaman 7 m, dan pada saat pengukuran mempunyai debit 41 .3 m3/s, serta kurva debitnya mengikuti formula: Q= 0.1649 x H 2.884 , dimana Q debit (m3/s dan H tinggi air dari dasar sungai (m.

  10. G2 cubic transition between two circles with shape control

    Science.gov (United States)

    Habib, Zulfiqar; Sakai, Manabu

    2009-01-01

    This paper describes a method for joining two circles with an S-shaped or with a broken back C-shaped transition curve, composed of at most two spiral segments. In highway and railway route design or car-like robot path planning, it is often desirable to have such a transition. It is shown that a single cubic curve can be used for blending or for a transition curve preserving G2 continuity with local shape control parameter and more flexible constraints. Provision of the shape parameter and flexibility provide freedom to modify the shape in a stable manner which is an advantage over previous work by Meek, Walton, Sakai and Habib.

  11. Efficient temperature-dependent Green's function methods for realistic systems: using cubic spline interpolation to approximate Matsubara Green's functions

    CERN Document Server

    Kananenka, Alexei A; Lan, Tran Nguyen; Gull, Emanuel; Zgid, Dominika

    2016-01-01

    The popular, stable, robust and computationally inexpensive cubic spline interpolation algorithm is adopted and used for finite temperature Green's function calculations of realistic systems. We demonstrate that with appropriate modifications the temperature dependence can be preserved while the Green's function grid size can be reduced by about two orders of magnitude by replacing the standard Matsubara frequency grid with a sparser grid and a set of interpolation coefficients. We benchmarked the accuracy of our algorithm as a function of a single parameter sensitive to the shape of the Green's function. Through numerous examples, we confirmed that our algorithm can be utilized in a systematically improvable, controlled, and black-box manner and highly accurate one- and two-body energies and one-particle density matrices can be obtained using only around 5% of the original grid points. Additionally, we established that to improve accuracy by an order of magnitude, the number of grid points needs to be double...

  12. Loss of superfluidity in the Bose-Einstein condensate in an optical lattice with cubic and quintic nonlinearity

    Energy Technology Data Exchange (ETDEWEB)

    Das, Priyam; Panigrahi, Prasanta K [Indian Institute of Science Education and Research (IISER), Salt Lake, Kolkata-700 106 (India); Vyas, Manan, E-mail: daspriyam3@gmail.co [Physical Research Laboratory, Navrangpura, Ahmedabad-380 009 (India)

    2009-12-28

    In a one-dimensional shallow optical lattice, in the presence of both cubic and quintic nonlinearity, a superfluid density wave is identified in a Bose-Einstein condensate. Interestingly, it ceases to exist when only one of these interactions is operative. We predict the loss of superfluidity through a classical dynamical phase transition, where modulational instability leads to the loss of phase coherence. In a certain parameter domain, the competition between lattice potential and the interactions is shown to give rise to a stripe phase, where atoms are confined in finite domains. In a pure two-body case, apart from the known superfluid and insulating phases, a density wave insulating phase is found to exist, possessing two frequency modulations commensurate with the lattice potential.

  13. National centers urged to team up, compete

    CERN Multimedia

    König, R

    2001-01-01

    A new report from Germany's scientific evaluatory body states that the national research centers are too insular. It urges the government to foster cooperation and competition between themselves and outside labs. It suggests using a USA style funding model with research programs that cut across many institutions rather than block grants to individual facilities (1 page).

  14. Body Image and Body Dysmorphic Concerns.

    Science.gov (United States)

    Tomas-Aragones, Lucia; Marron, Servando E

    2016-08-23

    Most people would like to change something about their bodies and the way that they look, but for some it becomes an obsession. A healthy skin plays an important role in a person's physical and mental wellbeing, whereas a disfiguring appearance is associated with body image concerns. Skin diseases such as acne, psoriasis and vitiligo produce cosmetic disfigurement and patients suffering these and other visible skin conditions have an increased risk of depression, anxiety, feelings of stigmatization and self-harm ideation. Body image affects our emotions, thoughts, and behaviours in everyday life, but, above all, it influences our relationships. Furthermore, it has the potential to influence our quality of life. Promotion of positive body image is highly recommended, as it is important in improving people's quality of life, physical health, and health-related behaviors. Dermatologists have a key role in identifying body image concerns and offering patients possible treatment options. PMID:27283435

  15. Cosmological evolution with the cubic order field derivative coupling

    Science.gov (United States)

    Minamitsuji, Masato

    2016-03-01

    We investigate cosmological evolution in the scalar-tensor theory with the field derivative coupling to the double-dual of the Riemann tensor (the cubic-type theory). The theory can be seen as the straightforward extension of the scalar-tensor with the quadratic order field derivative coupling to the Einstein tensor (the quadratic-type theory). Both the field derivative couplings to the Einstein tensor and the double-dual of the Riemann tensor have been argued in terms of the successful realization of the self-tuning of the cosmological constant within the Horndeski theory. Assuming the constant potential given by the sum of the cosmological constant and the quantum vacuum energy, the shift symmetry for the scalar field and no matter fields, in the spatially-flat Friedmann-Lemaître-Robertson-Walker spacetime, we can reduce the set of the field equations to the first-order ordinary nonlinear differential equation for the Hubble parameter, showing the existence of the self-tuned and runaway de Sitter solutions, in addition to the standard de Sitter solutions in general relativity and the finite Hubble singularities which can be reached within the finite time. We then argue the possible cosmological evolution in terms of the values of the effective cosmological constant, the kinetic coupling constants and the initial Hubble parameter. Although the behavior of the universe around each of the de Sitter solutions as well as the finite time singularities is very similar in both theories, we find that the crucial difference appears in terms of no bounce or turnaround behavior across the vanishing Hubble parameter as well as no limitation for the range of the Hubble parameter in the cubic-type theory.

  16. Wingless Flight: The Lifting Body Story

    Science.gov (United States)

    Reed, R. Dale; Lister, Darlene (Editor); Huntley, J. D. (Editor)

    1997-01-01

    Wingless Flight tells the story of the most unusual flying machines ever flown, the lifting bodies. It is my story about my friends and colleagues who committed a significant part of their lives in the 1960s and 1970s to prove that the concept was a viable one for use in spacecraft of the future. This story, filled with drama and adventure, is about the twelve-year period from 1963 to 1975 in which eight different lifting-body configurations flew. It is appropriate for me to write the story, since I was the engineer who first presented the idea of flight-testing the concept to others at the NASA Flight Research Center. Over those twelve years, I experienced the story as it unfolded day by day at that remote NASA facility northeast of los Angeles in the bleak Mojave Desert. Benefits from this effort immediately influenced the design and operational concepts of the winged NASA Shuttle Orbiter. However, the full benefits would not be realized until the 1990s when new spacecraft such as the X-33 and X-38 would fully employ the lifting-body concept. A lifting body is basically a wingless vehicle that flies due to the lift generated by the shape of its fuselage. Although both a lifting reentry vehicle and a ballistic capsule had been considered as options during the early stages of NASA's space program, NASA initially opted to go with the capsule. A number of individuals were not content to close the book on the lifting-body concept. Researchers including Alfred Eggers at the NASA Ames Research Center conducted early wind-tunnel experiments, finding that half of a rounded nose-cone shape that was flat on top and rounded on the bottom could generate a lift-to-drag ratio of about 1.5 to 1. Eggers' preliminary design sketch later resembled the basic M2 lifting-body design. At the NASA Langley Research Center, other researchers toyed with their own lifting-body shapes. Meanwhile, some of us aircraft-oriented researchers at the, NASA Flight Research Center at Edwards Air

  17. Alzheimer's Disease Research Centers

    Science.gov (United States)

    ... Plan National Alzheimer's Project Act (NAPA) About ADEAR Alzheimer's Disease Research Centers The National Institute on Aging ... Repository for Alzheimer's Disease ADC Directory Arizona Arizona Alzheimer’s Disease Center/Sun Health Research Institute Eric Reiman, ...

  18. New Mexico Convention Centers

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset provides an initial version of the locations of convention centers in New Mexico, in point form, with limited attributes, compiled using available data...

  19. Day Care Centers

    Data.gov (United States)

    Department of Homeland Security — This database contains locations of day care centers for 50 states and Washington D.C. and Puerto Rico. The dataset only includes center based day care locations...

  20. NIH Clinical Centers

    Data.gov (United States)

    Federal Laboratory Consortium — The NIH Clinical Center consists of two main facilities: The Mark O. Hatfield Clinical Research Center, which opened in 2005, houses inpatient units, day hospitals,...

  1. Tornadoes: A Center Approach.

    Science.gov (United States)

    Christman-Rothlein, Liz; Meinbach, Anita M.

    1981-01-01

    Information is given on how to put together a learning center. Discusses information and activity packets for a complete learning center on tornadoes including objectives, directions, materials, photographs of physical arrangements, and posttest. (DC)

  2. Center for Functional Nanomaterials

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Functional Nanomaterials (CFN) explores the unique properties of materials and processes at the nanoscale. The CFN is a user-oriented research center...

  3. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety Education Centers OnSafety Blog Neighborhood Safety Network Community Outreach Resource Center CO Poster Contest Toy Recall ... of the external site as its information collection practices may differ from ours. Linking to this external ...

  4. America's Blood Centers

    Science.gov (United States)

    ... or less. Please donate now! Full Stoplight Report America's Blood Centers is... FEATURED TODAY Support the Foundation ... purchase will be donated to the Foundation for America's Blood Centers! Simply Click Here! "We Are" This ...

  5. Hydrologic Engineering Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Hydrologic Engineering Center (HEC), an organization within the Institute for Water Resources, is the designated Center of Expertise for the U.S. Army Corps of...

  6. RSW Cell Centered Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — New cell centered grids are generated to complement the node-centered ones uploaded. Six tarballs containing the coarse, medium, and fine mixed-element and pure...

  7. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Home / Safety Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible ...

  8. BKG Data Center

    Science.gov (United States)

    Thorandt, Volkmar; Wojdziak, Reiner

    2013-01-01

    This report summarizes the activities and background information of the IVS Data Center for the year 2012. Included is information about functions, structure, technical equipment, and staff members of the BKG Data Center.

  9. ACTS data center

    Science.gov (United States)

    Syed, Ali; Vogel, Wolfhard J.

    1993-01-01

    Viewgraphs on ACTS Data Center status report are included. Topics covered include: ACTS Data Center Functions; data flow overview; PPD flow; RAW data flow; data compression; PPD distribution; RAW Data Archival; PPD Audit; and data analysis.

  10. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon monoxide, also known ... Install one and check its batteries regularly. View Information About CO Alarms Other CO Topics Safety Tips ...

  11. National Farm Medicine Center

    Science.gov (United States)

    ... Staff Agricultural Health and Safety Core Units Children's Center Cultivate Newsletter Journal of Agromedicine Milestones Auction of ... Farm Medicine, Rural Health & Safety National Farm Medicine Center Established in 1981 in response to occupational health ...

  12. Transplant Center Directory

    Science.gov (United States)

    ... mission. Learn more. My Account News Search Transplant Center Search Use the tools below to find a ... or enter your diagnosis to search for transplant centers. Select state(s) (optional) Enter diagnosis (optional) Please select ...

  13. NIST Diffusion Data Center

    Science.gov (United States)

    NIST Diffusion Data Center (Web, free access)   The NIST Diffusion Data Center is a collection of over 14,100 international papers, theses, and government reports on diffusion published before 1980.

  14. Lewy Body Dementia Diagnosis

    Science.gov (United States)

    ... Diagnosis Symptoms Treatment Options Help end Lewy body dementia now! Donate Diagnosis An experienced clinician within the ... an experienced diagnostic team skilled in Lewy body dementia. A thorough dementia diagnostic evaluation includes physical and ...

  15. Lewy Body Dementia Research

    Science.gov (United States)

    ... Research Abstracts Clinical Trials Help end Lewy body dementia now! Donate Research Links Treating Psychosis in Parkinson’s ... The use of antipsychotic medications in Lewy body dementias is a known challenge. Are the medications helpful ...

  16. About Body Water

    Science.gov (United States)

    ... Insulin Delivery Additional Content Medical News About Body Water By James L. Lewis, III, MD NOTE: This ... Version. DOCTORS: Click here for the Professional Version Water Balance About Body Water Dehydration Overhydration Water accounts ...

  17. Abstract: Body Work

    DEFF Research Database (Denmark)

    Otto, Lene

    2012-01-01

    This panel will explore the usefulness of the term ‘body work’ in cultural history. Body work is understood as work focusing on the bodies of others as component in a range of occupations in health and social care, as well as in unpaid work in the family. How can the notion of body work inform...... cultural history of health and illness whether through a micro-social focus on the intercorporeal aspects of work in health and social care, or through clarifying our understanding of the times and spaces of work, or through highlighting the relationship between mundane body work and global processes....... The British sociologist Julia Twigg has introduced and explored the term `bodywork', most recently in Body Work in Health and Social Care - Critical Themes, New Agendas (2011). She extends the term body work from applying to the work that individuals undertake on their own bodies, often as part of regimens...

  18. Body mass index

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007196.htm Body mass index To use the sharing features on this ... your height is to figure out your body mass index (BMI). You and your health care provider ...

  19. Written on the Body

    DEFF Research Database (Denmark)

    Christiansen, Steen Ledet

    Our bodies define a border between ourselves and the world around us. However we might feel about our body, it is what we present to the world. Victoria L. Blum in her book Flesh Wounds discusses how bodies are a form of inkblots, where discontent is projected onto. As bodies can be modified, we...... to the photo shoots, as the models remain in control, not the photographer. Marked by their body modifications, the Suicide Girls (as they call themselves), they actively attempt to subvert the typical pin-up conventions, by transgressing mainstream standards of beauty. In what seems remarkably...... similar to Judith Butler's account of subversive bodily acts, the pin-up shoots of the Suicide Girls mount a critique of a culture's view of the body as a natural entity. Cultural borders are crossed, as the bodies of the Suicide Girls embed ink into their bodies in the form of tattoos, and gender is...

  20. Efficacy of tibolone and raloxifene for the maintenance of skeletal muscle strength, bone mineral density, balance, body composition, cognitive function, mood/depression, anxiety and quality of life/well-being in late postmenopausal women ≥ 70 years: Study design of a randomized, double-blind, double-dummy, placebo-controlled, single-center trial

    Directory of Open Access Journals (Sweden)

    Grobbee Diederick E

    2008-06-01

    Full Text Available Abstract Background Postmenopausal women are prone to develop functional disabilities as a result of reduction in muscle strength and muscle mass caused by diminished levels of female sex hormones. While hormone replacement therapy may counteract these changes, conventional hormone replacement therapy is associated with potential harmful effects, such as an increased risk of breast cancer, and its prescription is not recommended. For this reason newer alternative drugs, such as tibolone, a synthetic steroid with estrogenic, progestogenic and androgenic activity, and raloxifene, a selective estrogen receptor modulator, may be more appropriate. This trial investigates the effect of tibolone and raloxifene on muscle strength. Methods We recruited 318 elderly women in our single-center randomized, double-blind, double-dummy, placebo-controlled trial. Participants were randomized to tibolone 1.25 mg (Org OD 14, Organon NV, the Netherlands plus placebo, raloxifene 60 mg (Evista®, Eli Lilly, United States plus placebo or two placebo tablets daily for 24 months. The primary aim is to determine if there is a difference between tibolone and placebo or if there is a difference between raloxifene and placebo. Primary endpoints are muscle strength and bone mineral density. The secondary endpoints are postural balance, body composition, cognitive function, anxiety, mood and quality of life. The secondary aim is to determine if there is a difference between tibolone and raloxifene. The measure of effect is the change from the baseline visit to the visits after 3 months, 6 months, 12 months, and 24 months. A follow-up measurement is planned at 30 months to determine whether any effects are sustained after cessation of the study. By December 2007 the blind will be broken and the data analyzed. Trial registration number NTR: 1232

  1. Data center cooling method

    Science.gov (United States)

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  2. Small Bodies, Big Discoveries: NASA's Small Bodies Education Program

    Science.gov (United States)

    Mayo, L.; Erickson, K. J.

    2014-12-01

    2014 is turning out to be a watershed year for celestial events involving the solar system's unsung heroes, small bodies. This includes the close flyby of comet C/2013 A1 / Siding Spring with Mars in October and the historic Rosetta mission with its Philae lander to comet 67P/Churyumov-Gerasimenko. Beyond 2014, the much anticipated 2015 Pluto flyby by New Horizons and the February Dawn Mission arrival at Ceres will take center stage. To deliver the excitement and wonder of our solar system's small bodies to worldwide audiences, NASA's JPL and GSFC education teams in partnership with NASA EDGE will reach out to the public through multiple venues including broadcast media, social media, science and math focused educational activities, observing challenges, interactive visualization tools like "Eyes on the Solar System" and more. This talk will highlight NASA's focused education effort to engage the public in small bodies mission science and the role these objects play in our understanding of the formation and evolution of the solar system.

  3. Zooplankton body composition

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    2013-01-01

    I compiled literature on zooplankton body composition, from protozoans to gelatinous plankton, and report allometric relations and average body composition. Zooplankton segregate into gelatinous and non-gelatinous forms, with few intermediate taxa (chaetognaths, polychaetes, and pteropods). In most...... groups body composition is size independent. Exceptions are protozoans, chaetognaths, and pteropods, where larger individuals become increasingly watery. I speculate about the dichotomy in body composition and argue that differences in feeding mechanisms and predator avoidance strategies favor either a...

  4. Three-body bound states in finite volume with EFT

    International Nuclear Information System (INIS)

    Three particles with large scattering length display a universal spectrum of three-body bound states called ''Efimov trimers''. We calculate the modification of the Efimov trimers of three identical bosons in a finite cubic box and compute the dependence of their energies on the box size using effective field theory. The renormalization of the effective field theory in the finite volume is explicitly verified. We investigate the effects of partial wave mixing and study the behavior of shallow trimers near the dimer energy. Finally, we present first results for the triton in a finite volume.

  5. Pathologically Collapsed Vertebral Body

    Directory of Open Access Journals (Sweden)

    Reza Saadat Mostafavi

    2010-05-01

    Full Text Available An 8-year-old boy, a case of CGD, presenting with quadriparesis "nFindings: Collapsed contiguous vertebral bodies"nSpared disks"nEpidural components extending one level above and below the involved vertebral bodies"nSignal of involved vertebral bodies: low on T1W and high on T2W image

  6. Identification of silver cubic structures during ultrasonication of chitosan AgNO3 solution.

    Science.gov (United States)

    Raghavendra, Gownolla Malegowd; Jung, Jeyoung; Kim, Dowan; Varaprasad, Kokkarachedu; Seo, Jongchul

    2016-11-01

    During ultrasonication of chitosan AgNO3 solution (10mM), silver cubic structures were identified along with other dispersed silver nanoparticles. Temperature influenced the formation of the cubic structures. Formation of the silver cubic structures occurred via initial formation of 'four petal flower-like' structures that underwent transformation to the "cubic morphology" in the latter stages. Aging of the reaction mixture led to formation of complete dendrites. These dendrites comprised a large quantity of silver nanoparticles. Upon repetition of the experiment with starch instead of chitosan, the identified silver cubic structures were completely absent, indicating that formation of the 'silver cubic structures' is dependent on the polysaccharide used. It is believed that the structural features of chitosan facilitate the formation of 'silver cubic structures' under ultrasonic conditions. The phenomena occurring during the experiments were evaluated via scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), ultraviolet-visible (UV-vis) spectra, transmission electron microscopy (TEM), and selected area electron diffraction (SAED) analysis. PMID:27516304

  7. Surface charges and optical characteristic of colloidal cubic SiC nanocrystals

    Science.gov (United States)

    Li, Yong; Chen, Changxin; Li, Jiang-Tao; Yang, Yun; Lin, Zhi-Ming

    2011-07-01

    Colloidal cubic silicon carbide (SiC) nanocrystals with an average diameter of 4.4 nm have been fabricated by anisotropic wet chemical etching of microsized cubic SiC powder. Fourier transform infrared spectra show that these cubic SiC nanocrystals contain carboxylic acid, SiH, CH, and CHx groups. UV/Vis absorption and photoluminescence (PL) spectroscopy clearly indicate that water and ethanol colloidal suspensions of the as-fabricated colloidal samples exhibit strong and above band gap blue and blue-green emissions. The cubic SiC nanocrystals show different surface charges in water and ethanol solutions due to the interaction of water molecules with polar Si-terminated surfaces of cubic SiC nanocrystals. The results explain the distinctive optical characteristics of colloidal cubic SiC nanocrystals in water and ethanol, and reveal that quantum confinement and surface charges play a great role in determining the optical characteristics of colloidal cubic SiC nanocrystals.

  8. Characterization, Microstructure, and Dielectric properties of cubic pyrochlore structural ceramics

    KAUST Repository

    Li, Yangyang

    2013-05-01

    The (BMN) bulk materials were sintered at 1050°C, 1100°C, 1150°C, 1200°C by the conventional ceramic process, and their microstructure and dielectric properties were investigated by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, Transmission electron microscopy (TEM) (including the X-ray energy dispersive spectrometry EDS and high resolution transmission electron microscopy HRTEM) and dielectric impedance analyzer. We systematically investigated the structure, dielectric properties and voltage tunable property of the ceramics prepared at different sintering temperatures. The XRD patterns demonstrated that the synthesized BMN solid solutions had cubic phase pyrochlore-type structure when sintered at 1050°C or higher, and the lattice parameter (a) of the unit cell in BMN solid solution was calculated to be about 10.56Å. The vibrational peaks observed in the Raman spectra of BMN solid solutions also confirmed the cubic phase pyrochlore-type structure of the synthesized BMN. According to the Scanning Electron Microscope (SEM) images, the grain size increased with increasing sintering temperature. Additionally, it was shown that the densities of the BMN ceramic tablets vary with sintering temperature. The calculated theoretical density for the BMN ceramic tablets sintered at different temperatures is about 6.7521 . The density of the respective measured tablets is usually amounting more than 91% and 5 approaching a maximum value of 96.5% for sintering temperature of 1150°C. The microstructure was investigated by using Scanning Transmission Electron Microscope (STEM), X-ray diffraction (XRD). Combined with the results obtained from the STEM and XRD, the impact of sintering temperature on the macroscopic and microscopic structure was discussed. The relative dielectric constant ( ) and dielectric loss ( ) of the BMN solid solutions were measured to be 161-200 and (at room temperature and 100Hz-1MHz), respectively. The BMN solid

  9. The growth of cubic silicon carbide on a compliant substrate

    Science.gov (United States)

    Mitchell, Sharanda; Soward, Ida

    1995-01-01

    Research has shown that silicon carbide grown on silicon and 6H silicon carbide has problems associated with these substrates. This is because silicon and silicon carbide has a 20% lattice mismatch and cubic silicon carbide has not been successfully achieved on 6H silicon carbide. We are investigating the growth of silicon carbide on a compliant substrate in order to grow defect free silicon carbide. This compliant substrate consists of silicon/silicon dioxide with 1200 A of single crystal silicon on the top layer. We are using this compliant substrate because there is a possibility that the silicon dioxide layer and the carbonized layer will allow the silicon lattice to shrink or expand to match the lattice of the silicon carbide. This would improve the electrical properties of the film for the use of device fabrication. When trying to grow silicon carbide, we observed amorphous film. To investigate, we examined the process step by step using RHEED. RHEED data showed that each step was amorphous. We found that just by heating the substrate in the presence of hydrogen it changed the crystal structure. When heated to 1000 C for 2 minutes, RHEED showed that there was an amorphous layer on the surface. We also heated the substrate to 900 C for 2 minutes and RHEED data showed that there was a deterioration of the single crystalline structure. We assumed that the presence of oxygen was coming from the sides of the silicon dioxide layer. Therefore, we evaporated 2500 A of silicon to all four edges of the wafer to try to enclose the oxygen. When heating the evaporated wafer to 900 C the RHEED data showed single crystalline structure however at 1000 C the RHEED data showed deterioration of the single crystalline structure. We conclude that the substrate itself is temperature dependent and that the oxygen was coming from the sides of the silicon dioxide layer. We propose to evaporate more silicon on the edges of the wafer to eliminate the escape of oxygen. this will allow

  10. Michel Foucault's bodies

    OpenAIRE

    Potte-Bonneville, Mathieu

    2012-01-01

    How is it possible for Foucault to present the body at the same time as the foundation and the result of history, as condition and horizon of the theory that takes hold of it ? One has to pay attention to the various registers in which Foucault distributes the acceptations ordinarily confused with the general notion of the body : from "my body" (as it appears in Merleau-Ponty's phenomenology) to "the body' (as it is understood by modern medicine) ; from this body as an object for positive exp...

  11. Noise-to-signal transition of a Brownian particle in the cubic potential: I. general theory

    Science.gov (United States)

    Filip, Radim; Zemánek, Pavel

    2016-06-01

    The noise-to-signal transitions are very interesting processes in physics, as they might transform environmental noise to useful mechanical effects. We theoretically analyze stochastic noise-to-signal transition of overdamped Brownian motion of a particle in the cubic potential. The particle reaches thermal equilibrium with its environment in the quadratic potential which is suddenly swapped to the cubic potential. We predict a simultaneous increase of both the displacement and signal-to-noise ratio in the cubic potential for the position linearly powered by the temperature of the particle environment. The short-time analysis and numerical simulations fully confirm different dynamical regimes of this noise-to-signal transition.

  12. Study of the cubic - to - monoclinic transformation in magnesia partially stabilized zirconia

    International Nuclear Information System (INIS)

    The transformation of the cubic phase to the stable monoclinic phase in ZrO2: 3%MgO quenched from 14500C to RT has been studied by X-ray diffractometry in order to explain the thermal hysteresis in the electrical conductivity. The monoclinic-to-cubic ratio has been measured for samples annealed in the 5000C-10000C temperature range. The results show that the decrease in the cubic phase content is the main responsible for the thermal hysteresis in the electrical conductivity of the magnesia partially stabilized zirconia solid electrolytes. (author)

  13. Chiral Surface Twists and Skyrmion Stability in Nanolayers of Cubic Helimagnets

    Science.gov (United States)

    Leonov, A. O.; Togawa, Y.; Monchesky, T. L.; Bogdanov, A. N.; Kishine, J.; Kousaka, Y.; Miyagawa, M.; Koyama, T.; Akimitsu, J.; Koyama, Ts.; Harada, K.; Mori, S.; McGrouther, D.; Lamb, R.; Krajnak, M.; McVitie, S.; Stamps, R. L.; Inoue, K.

    2016-08-01

    Theoretical analysis and Lorentz transmission electron microscopy (LTEM) investigations in an FeGe wedge demonstrate that chiral twists arising near the surfaces of noncentrosymmetric ferromagnets [Meynell et al., Phys. Rev. B 90, 014406 (2014)] provide a stabilization mechanism for magnetic Skyrmion lattices and helicoids in cubic helimagnet nanolayers. The magnetic phase diagram obtained for freestanding cubic helimagnet nanolayers shows that magnetization processes differ fundamentally from those in bulk cubic helimagnets and are characterized by the first-order transitions between modulated phases. LTEM investigations exhibit a series of hysteretic transformation processes among the modulated phases, which results in the formation of the multidomain patterns.

  14. Evidence of reaction rate influencing cubic and hexagonal phase formation process in CdS nanocrystals

    Science.gov (United States)

    Deka, Kuldeep; Kalita, M. P. C.

    2016-05-01

    CdS nanocrystals are synthesized by co-precipitation method using 2-mercaptoethanol (ME) as capping agent. Cubic, hexagonal and their mixture are obtained by varying the ME concentration. Lower (higher) ME concentration results in cubic (hexagonal) phase. The crystallite sizes are in the range 3-7 nm. Increase in ME concentration lead to lower reaction rate between Cd2+ and S2- of the precursors, and slower reaction rate is found to favor hexagonal phase formation over the cubic one in CdS nanocrystals. Role of reaction rate in the phase formation process provides a way to synthesize CdS nanocrystals in desired crystal phase.

  15. On the Structure of Cubic and Quartic Polynomials

    CERN Document Server

    Haramaty, Elad

    2009-01-01

    In this paper we study the structure of polynomials of degree three and four that have high bias or high Gowers norm, over arbitrary prime fields. In particular we obtain the following results. 1. We give a canonical representation for degree three or four polynomials that have a significant bias (i.e. they are not equidistributed). This result generalizes the corresponding results from the theory of quadratic forms. It also significantly improves the results of Green and Tao and Kaufman and Lovett for such polynomials. 2. For the case of degree four polynomials with high Gowers norm we show that (a subspace of co-dimension O(1) of) F^n can be partitioned to subspaces of dimension Omega(n) such that on each of the subspaces the polynomial is equal to some degree three polynomial. It was shown by Green and Tao and by Lovett, Meshulam and Samorodnitsky that a quartic polynomial with a high Gowers norm is not necessarily correlated with any cubic polynomial. Our result shows that a slightly weaker statement does...

  16. Natural Convection in a Finned Rayleigh-Benard Cubical Enclosure

    International Nuclear Information System (INIS)

    The papers deals with a numerical 3D study of natural convection in a finned Rayleigh-Be nard (RB) cubical enclosure. A single fin with a thickness of 10 pour cent of the cavity side (and a height of 50 pour cent ) is placed vertically on the bottom hot wall at TH. The working fluid is air with Prandtl number Pr = 0.71 and the Rayleigh number (Ra) varies from 103 to 105. The solid-to-fluid thermal conductivity ratio (kR) was fixed at RK = 7000, corresponding to a metal of high conductivity. The top wall is at the temperature TC H and the remaining four surfaces are insulated. Inside the RB enclosure, the flow structure and the temperature distribution are presented in terms of mean velocity vector plots and isotherm plots. The effects of the Rayleigh number on the mean heat transfer rate through the cold wall are presented and discussed. A correlation between the averaged Nusselt number through the top wall and Ra is proposed

  17. Taylor line swimming in microchannels and cubic lattices of obstacles.

    Science.gov (United States)

    Münch, Jan L; Alizadehrad, Davod; Babu, Sujin B; Stark, Holger

    2016-09-21

    Microorganisms naturally move in microstructured fluids. Using the simulation method of multi-particle collision dynamics, we study in two dimensions an undulatory Taylor line swimming in a microchannel and in a cubic lattice of obstacles, which represent simple forms of a microstructured environment. In the microchannel the Taylor line swims at an acute angle along a channel wall with a clearly enhanced swimming speed due to hydrodynamic interactions with the bounding wall. While in a dilute obstacle lattice swimming speed is also enhanced, a dense obstacle lattice gives rise to geometric swimming. This new type of swimming is characterized by a drastically increased swimming speed. Since the Taylor line has to fit into the free space of the obstacle lattice, the swimming speed is close to the phase velocity of the bending wave traveling along the Taylor line. While adjusting its swimming motion within the lattice, the Taylor line chooses a specific swimming direction, which we classify by a lattice vector. When plotting the swimming velocity versus the magnitude of the lattice vector, all our data collapse on a single master curve. Finally, we also report more complex trajectories within the obstacle lattice. PMID:27510576

  18. Tribological properties of cubic, amorphous and hexagonal boron nitride films

    International Nuclear Information System (INIS)

    Cubic boron nitride (c-BN), amorphous boron nitride (a-BN) and hexagonal boron nitride (h-BN) films were deposited onto a silicon substrate using a magnetically enhanced plasma ion plating method which has a hot cathode plasma discharge in a parallel magnetic field. A reciprocating tribometer was used to examine friction and wear properties for these three BN films, whose crystal structures were identified by IR spectroscopy. The tribological properties were revealed to be highly dependent on the films' crystal structures. The c-BN film showed the highest wear and peeling resistance of the tested films. The lubricating performance of the c-BN film proved significant with a long lubricating life and low friction. In contrast, the a-BN and h-BN films showed short lubricating endurance lives and large friction changes in spite of the fact that they are good in general as solid lubricants. These unexpected results are speculated to reflect the premature debonding of the h-BN and a-BN films during sliding and the subsequent discharge of their flakes out of the nip between the substrate and the ball indenter, owing to their lower adhesion to the substrate. (orig.)

  19. Serial femtosecond crystallography of soluble proteins in lipidic cubic phase

    Directory of Open Access Journals (Sweden)

    Raimund Fromme

    2015-09-01

    Full Text Available Serial femtosecond crystallography (SFX at X-ray free-electron lasers (XFELs enables high-resolution protein structure determination using micrometre-sized crystals at room temperature with minimal effects from radiation damage. SFX requires a steady supply of microcrystals intersecting the XFEL beam at random orientations. An LCP–SFX method has recently been introduced in which microcrystals of membrane proteins are grown and delivered for SFX data collection inside a gel-like membrane-mimetic matrix, known as lipidic cubic phase (LCP, using a special LCP microextrusion injector. Here, it is demonstrated that LCP can also be used as a suitable carrier medium for microcrystals of soluble proteins, enabling a dramatic reduction in the amount of crystallized protein required for data collection compared with crystals delivered by liquid injectors. High-quality LCP–SFX data sets were collected for two soluble proteins, lysozyme and phycocyanin, using less than 0.1 mg of each protein.

  20. Serial femtosecond crystallography of soluble proteins in lipidic cubic phase.

    Science.gov (United States)

    Fromme, Raimund; Ishchenko, Andrii; Metz, Markus; Chowdhury, Shatabdi Roy; Basu, Shibom; Boutet, Sébastien; Fromme, Petra; White, Thomas A; Barty, Anton; Spence, John C H; Weierstall, Uwe; Liu, Wei; Cherezov, Vadim

    2015-09-01

    Serial femtosecond crystallography (SFX) at X-ray free-electron lasers (XFELs) enables high-resolution protein structure determination using micrometre-sized crystals at room temperature with minimal effects from radiation damage. SFX requires a steady supply of microcrystals intersecting the XFEL beam at random orientations. An LCP-SFX method has recently been introduced in which microcrystals of membrane proteins are grown and delivered for SFX data collection inside a gel-like membrane-mimetic matrix, known as lipidic cubic phase (LCP), using a special LCP microextrusion injector. Here, it is demonstrated that LCP can also be used as a suitable carrier medium for microcrystals of soluble proteins, enabling a dramatic reduction in the amount of crystallized protein required for data collection compared with crystals delivered by liquid injectors. High-quality LCP-SFX data sets were collected for two soluble proteins, lysozyme and phycocyanin, using less than 0.1 mg of each protein. PMID:26306196

  1. Serial femtosecond crystallography of soluble proteins in lipidic cubic phase

    Energy Technology Data Exchange (ETDEWEB)

    Fromme, Raimund; Ishchenko, Andrii; Metz, Markus; Chowdhury, Shatabdi Roy; Basu, Shibom; Boutet, Sébastien; Fromme, Petra; White, Thomas A.; Barty, Anton; Spence, John C. H.; Weierstall, Uwe; Liu, Wei; Cherezov, Vadim

    2015-08-04

    Serial femtosecond crystallography (SFX) at X-ray free-electron lasers (XFELs) enables high-resolution protein structure determination using micrometre-sized crystals at room temperature with minimal effects from radiation damage. SFX requires a steady supply of microcrystals intersecting the XFEL beam at random orientations. An LCP–SFX method has recently been introduced in which microcrystals of membrane proteins are grown and delivered for SFX data collection inside a gel-like membrane-mimetic matrix, known as lipidic cubic phase (LCP), using a special LCP microextrusion injector. Here, it is demonstrated that LCP can also be used as a suitable carrier medium for microcrystals of soluble proteins, enabling a dramatic reduction in the amount of crystallized protein required for data collection compared with crystals delivered by liquid injectors. High-quality LCP–SFX data sets were collected for two soluble proteins, lysozyme and phycocyanin, using less than 0.1 mg of each protein.

  2. Three-dimensional natural convection in finned cubical enclosures

    International Nuclear Information System (INIS)

    Three-dimensional natural convection of air in a cubical enclosure with a fin on the hot wall is numerically investigated for Rayleigh numbers of 103-106. The fin, with a thickness of 1/10 of the cavity side, is placed horizontally on the hot wall. The solid to fluid thermal conductivity ratio (R k) and the fin width are varied. Because the fin is shorter than the cavity side, the cold flow sweeps the lower fin face and the hot wall at the clearances between the fin sides and the lateral walls, where high vertical velocities are reached. The fin inhibits the frontal and lateral access of fluid to the upper fin face, especially at low Rayleigh numbers. Low values of R k cause heat transfer reductions. The contribution of the fin faces increases at high R k causing heat transfer enhancements above 20%, which exceed the ones obtained in most two-dimensional studies. In the range of Ra from 105 to 106, maximum heat transfer rates are found for dimensionless fin widths of 0.6 and 0.8 respectively. It is concluded that for 105 ≤ Ra ≤ 106 a fin of partial width is more effective in promoting heat transfer than a fin of full width

  3. The Structure of the Cubic Coincident Site Lattice Rotation Group

    Energy Technology Data Exchange (ETDEWEB)

    Reed, B W; Minich, R W; Rudd, R E; Kumar, M

    2004-01-13

    This work is intended to be a mathematical underpinning for the field of grain boundary engineering and its relatives. The interrelationships within the set of rotations producing coincident site lattices in cubic crystals are examined in detail. Besides combining previously established but widely scattered results into a unified context, the present work details newly developed representations of the group structure in terms of strings of generators (based on quaternionic number theory, and including uniqueness proofs and rules for algebraic manipulation) as well as an easily visualized topological network model. Important results that were previously obscure or not universally understood (e.g. the {Sigma} combination rule governing triple junctions) are clarified in these frameworks. The methods also facilitate several general observations, including the very different natures of twin-limited structures in two and three dimensions, the inadequacy of the {Sigma} combination rule to determine valid quadruple nodes, and a curious link between allowable grain boundary assignments and the four-color map theorem. This kind of understanding is essential to the generation of realistic statistical models of grain boundary networks (particularly in twin-dominated systems) and is especially applicable to the field of grain boundary engineering.

  4. A simple calibration of a whole-body counter for the measurement of total body potassium in humans

    International Nuclear Information System (INIS)

    A simple calibration procedure for the Inshas whole body counter for evaluating total body potassium has been adopted. More than 120 Egyptian employees in the Nuclear Research Center (N.R.C.) were studied for their total body potassium (TBK). The potassium values were found to have an average of 2.85±0.57 g K kg-1 body weight for males and 2.62±0.52 g K kg-1 for females, which are higher than the recommended value given for reference man by ICRP. The TBK varied directly with body build index and is slightly sex dependent (Author)

  5. Criteria of an estimation statodynamic stability of sportsman body and system of bodies in difficult coordination sports.

    Directory of Open Access Journals (Sweden)

    Boloban V.N.

    2012-04-01

    Full Text Available Criteria of an estimation statodynamic stability of sportsman body and system of bodies in difficult coordination sports are developed and experimentally proved. It is established that length of the general center of pressure trajectory of a body on a support, frequency of fluctuations of a body, a parity of amplitude of fluctuations of a body and frequency, symmetry and asymmetry of movements in the course of a body pose regulation, length of a trajectory of a control point moving on a trunk in the field of a sacrum in system of cooperating bodies are authentic signs of sports orientation, an estimation of sports technics of exercises and training by it. Criteria are a criterion of an estimation of a body balance in the course of sports exercises performance; allow to carry out effective sports preparation.

  6. Unified treatment of coupled optical and acoustic phonons in piezoelectric cubic materials

    DEFF Research Database (Denmark)

    Willatzen, Morten; Wang, Zhong Lin

    2015-01-01

    A unified treatment of coupled optical and acoustic phonons in piezoelectric cubic materials is presented whereby the lattice displacement vector and the internal ionic displacement vector are found simultaneously. It is shown that phonon couplings exist in pairs only; either between the electric...... potential and the lattice displacement coordinate perpendicular to the phonon wave vector or between the two other lattice displacement components. The former leads to coupled acousto-optical phonons by virtue of the piezoelectric effect. We then establish three new conjectures that entirely stem from...... piezoelectricity in a cubic structured material slab. First, it is shown that isolated optical phonon modes generally cannot exist in piezoelectric cubic slabs. Second, we prove that confined acousto-optical phonon modes only exist for a discrete set of in-plane wave numbers in piezoelectric cubic slabs. Third...

  7. Is inner core seismic anisotropy a marker of plastic flow of cubic iron?

    CERN Document Server

    Lincot, A; Cardin, Philippe

    2015-01-01

    This paper investigates whether observations of seismic anisotropy are compatible with a cubic structure of the inner core Fe alloy. We assume that anisotropy is the result of plastic deformation within a large scale flow induced by preferred growth at the inner core equator. Based on elastic moduli from the literature, bcc- or fcc-Fe produce seismic anisotropy well below seismic observations ($\\textless{}0.4\\%$). A Monte-Carlo approach allows us to generalize this result to any form of elastic anisotropy in a cubic system. Within our model, inner core global anisotropy is not compatible with a cubic structure of Fe alloy. Hence, if the inner core material is indeed cubic, large scale coherent anisotropic structures, incompatible with plastic deformation induced by large scale flow, must be present.

  8. Effective optical path length for tandem diffuse cubic cavities as gas absorption cell

    International Nuclear Information System (INIS)

    Tandem diffuse cubic cavities designed by connecting two single diffuse cubic-shaped cavities, A and B, with an aperture (port fraction fap) in the middle of the connecting baffle was developed as a gas absorption cell. The effective optical path length (EOPL) was evaluated by comparing the oxygen absorption signal in the cavity and in air based on tunable diode laser absorption spectroscopy (TDLAS). Experimental results manifested an enhancement of EOPL for the tandem diffuse cubic cavities as the decrease of fap and can be expressed as the sum of EOPL of two single cubic cavities at fap < 0.01, which coincided well with theoretical analysis. The simulating EOPL was smaller than experimental results at fap > 0.01, which indicated that back scattering light from cavity B to cavity A cannot be ignored at this condition. (paper)

  9. Symplectic Structures for the Cubic Schrodinger equation in the periodic and scattering case

    OpenAIRE

    Vaninsky, K. L.

    2000-01-01

    We develop a unified approach for construction of symplectic forms for 1D integrable equations with the periodic and rapidly decaying initial data. As an example we consider the cubic nonlinear Schr\\"{o}dinger equation.

  10. Blocking temperature of interacting magnetic nanoparticles with uniaxial and cubic anisotropies from Monte Carlo simulations

    Science.gov (United States)

    Russier, V.

    2016-07-01

    The low temperature behavior of densely packed interacting spherical single domain nanoparticles (MNP) is investigated by Monte Carlo simulations in the framework of an effective one spin model. The particles are distributed through a hard sphere like distribution with periodic boundary conditions and interact through the dipole dipole interaction (DDI) with an anisotropy energy including both cubic and uniaxial symmetry components. The cubic component is shown to play a sizable role on the value of the blocking temperature Tb only when the MNP easy axes are parallel to the cubic easy direction ([111] direction for a negative cubic anisotropy constant). The nature of the collective low temperature state, either ferromagnetic or spin glass like, is found to depend on the ratio of the anisotropy to the dipolar energies characterizing partly the disorder in the system.

  11. Relativistic Guiding Center Equations

    Energy Technology Data Exchange (ETDEWEB)

    White, R. B. [PPPL; Gobbin, M. [Euratom-ENEA Association

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  12. The Mallory body

    DEFF Research Database (Denmark)

    Jensen, K; Gluud, C

    1994-01-01

    , a variety of experimental drugs have been developed that cause Mallory body formation, but markedly different cell dynamics and metabolic pathways may raise questions about the relevance of such animal models for human Mallory body formation. In conclusion, the Mallory body is indicative but not......To aid understanding of markers of disease and predictors of outcome in alcohol-exposed systems, we undertook a literature survey of more than 700 articles to view the morphological characteristics and the clinical and experimental epidemiology of the Mallory body. Mallory bodies are filaments of...... electron microscopy (with fibrillar structure parallel, random or absent), they remain stereotypical manifestations of hepatocyte injury. A summary of the conditions associated with Mallory bodies in the literature and their validity and potential etiological relationships is presented and discussed...

  13. Airline Operation Center Workstation

    Data.gov (United States)

    Department of Transportation — The Airline Operation Center Workstation (AOC Workstation) represents equipment available to users of the National Airspace system, outside of the FAA, that enables...

  14. Chemical Security Analysis Center

    Data.gov (United States)

    Federal Laboratory Consortium — In 2006, by Presidential Directive, DHS established the Chemical Security Analysis Center (CSAC) to identify and assess chemical threats and vulnerabilities in the...

  15. Small Business Development Center

    Data.gov (United States)

    Small Business Administration — Small Business Development Centers (SBDCs) provide assistance to small businesses and aspiring entrepreneurs throughout the United States and its territories. SBDCs...

  16. Electron Microscopy Center (EMC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

  17. Center for Deployment Psychology

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Deployment Psychology was developed to promote the education of psychologists and other behavioral health specialists about issues pertaining to the...

  18. Data Center at NICT

    Science.gov (United States)

    Ichikawa, Ryuichi; Sekido, Mamoru

    2013-01-01

    The Data Center at the National Institute of Information and Communications Technology (NICT) archives and releases the databases and analysis results processed at the Correlator and the Analysis Center at NICT. Regular VLBI sessions of the Key Stone Project VLBI Network were the primary objective of the Data Center. These regular sessions continued until the end of November 2001. In addition to the Key Stone Project VLBI sessions, NICT has been conducting geodetic VLBI sessions for various purposes, and these data are also archived and released by the Data Center.

  19. Test Control Center (TCC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Test Control Center (TCC) provides a consolidated facility for planning, coordinating, controlling, monitoring, and analyzing distributed test events. ,The TCC...

  20. Environmental Modeling Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Environmental Modeling Center provides the computational tools to perform geostatistical analysis, to model ground water and atmospheric releases for comparison...

  1. Computer-aided analytical control of diamond and cubic boron nitride grits

    International Nuclear Information System (INIS)

    Methodical and information aspects of the superhard materials powder uniformity as a characteristics of the powder quality are discussed. Computer-aided analytical methods of the rapid diagnostics of the sieve granulometric composition and the external specific surface of diamond and cubic boron nitride grits are described. The results of the application of the developed methods and software to standard powders of synthetic diamond and cubic boron nitride are given

  2. Epitaxial relationships for hexagonal-to-cubic phase transition in a block copolymer mixture

    DEFF Research Database (Denmark)

    Schulz, M.F.; Bates, F.S.; Almdal, K.;

    1994-01-01

    Small-angle neutron scattering experiments have revealed an epitaxial relationship between the hexagonal cylinder phase, and a bicontinuous cubic phase with Ia3dBAR space group symmetry, in a poly(styrene)-poly(2-vinylpyridine) diblock copolymer mixture. Proximity to the order-disorder transition...... and an inelastic low frequency rheological response suggest that the cubic phase is stabilized by fluctuations. These results identify block copolymers as model compounds for investigating the thermodynamics and dynamics of complex ''soft'' condensed matter....

  3. Blocking temperature of interacting magnetic nanoparticles with uniaxial and cubic anisotropies from Monte Carlo simulations

    OpenAIRE

    V. Russier

    2016-01-01

    The low temperature behavior of densely packed interacting spherical single domain nanoparticles (MNP) is investigated by Monte Carlo simulations in the framework of an effective one spin model. The particles are distributed through a hard sphere like distribution with periodic boundary conditions and interact through the dipole dipole interaction (DDI) with an anisotropy energy including both cubic and uniaxial symmetry components. The cubic component is shown to play a sizable role on the v...

  4. Numerical Method Using Cubic Trigonometric B-Spline Technique for Nonclassical Diffusion Problems

    OpenAIRE

    Muhammad Abbas; Ahmad Abd. Majid; Ahmad Izani Md Ismail; Abdur Rashid

    2014-01-01

    A new two-time level implicit technique based on cubic trigonometric B-spline is proposed for the approximate solution of a nonclassical diffusion problem with nonlocal boundary constraints. The standard finite difference approach is applied to discretize the time derivative while cubic trigonometric B-spline is utilized as an interpolating function in the space dimension. The technique is shown to be unconditionally stable using the von Neumann method. Several numerical examples are discusse...

  5. Ising-like phase transition of an n-component Eulerian face-cubic model

    Science.gov (United States)

    Ding, Chengxiang; Guo, Wenan; Deng, Youjin

    2013-11-01

    By means of Monte Carlo simulations and a finite-size scaling analysis, we find a critical line of an n-component Eulerian face-cubic model on the square lattice and the simple cubic lattice in the region v>1, where v is the bond weight. The phase transition belongs to the Ising universality class independent of n. The critical properties of the phase transition can also be captured by the percolation of the complement of the Eulerian graph.

  6. Epitaxial Growth of Cubic Crystalline Semiconductor Alloys on Basal Plane of Trigonal or Hexagonal Crystal

    Science.gov (United States)

    Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor)

    2011-01-01

    Hetero-epitaxial semiconductor materials comprising cubic crystalline semiconductor alloys grown on the basal plane of trigonal and hexagonal substrates, in which misfit dislocations are reduced by approximate lattice matching of the cubic crystal structure to underlying trigonal or hexagonal substrate structure, enabling the development of alloyed semiconductor layers of greater thickness, resulting in a new class of semiconductor materials and corresponding devices, including improved hetero-bipolar and high-electron mobility transistors, and high-mobility thermoelectric devices.

  7. Frequency domain analysis of a dimensionless cubic nonlinear damping system subject to harmonic input

    OpenAIRE

    Jing, X. J.; Z.Q. Lang

    2008-01-01

    The effects of cubic nonlinear damping on the system output spectrum are theoretically studied through a dimensionless mass-spring-damping system model subject to a harmonic input, based on the Volterra series approximation. It is for the first time shown theoretically that the cubic nonlinear damping has little effect on the system output spectrum at high or low frequencies but drives the system output spectrum to be an alternative series at the natural frequency 1 such that the system ou...

  8. Structural insights into the cubic-hexagonal phase transition kinetics of monoolein modulated by sucrose solutions

    OpenAIRE

    Reese, Caleb W.; Strango, Zachariah I.; Dell, Zachary R.; Tristram-Nagle, Stephanie; Harper, Paul E.

    2015-01-01

    Using DSC (differential scanning calorimetry), we measure the kinetics of the cubic-HII phase transition of monoolein in bulk sucrose solutions. We find that the transition temperature is dramatically lowered, with each 1 mol/kg of sucrose concentration dropping the transition by 20 °C. The kinetics of this transition also slow greatly with increasing sucrose concentration. For low sucrose concentrations, the kinetics are asymmetric, with the cooling (HII-cubic) transition taking twice as lon...

  9. Strain dependent electron spin dynamics in bulk cubic GaN

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A.; Buß, J. H.; Hägele, D.; Rudolph, J. [Arbeitsgruppe Spektroskopie der kondensierten Materie, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum (Germany); Schupp, T.; Zado, A.; As, D. J. [Department of Physics, University of Paderborn, Warburger Str. 100, D-33095 Paderborn (Germany)

    2015-03-07

    The electron spin dynamics under variable uniaxial strain is investigated in bulk cubic GaN by time-resolved magneto-optical Kerr-rotation spectroscopy. Spin relaxation is found to be approximately independent of the applied strain, in complete agreement with estimates for Dyakonov-Perel spin relaxation. Our findings clearly exclude strain-induced relaxation as an effective mechanism for spin relaxation in cubic GaN.

  10. Nonperturbative RG analysis of five-dimensional O(N) models with cubic interactions

    CERN Document Server

    Kamikado, Kazuhiko

    2016-01-01

    We reconsider critical properties of O(N) scalar models with cubic interactions in $d>4$ dimensions using functional renormalization group equations. Working at next-to-leading order in the derivative expansion, we find non-trivial IR fixed points at small and intermediate N from beta functions for relevant cubic terms. The putative fixed point at large N suggested recently by higher spin holography and the epsilon-expansion is also discussed, with an emphasis on stability of the effective potential.

  11. The double-end-pumped cubic Nd:YVO4 laser: Temperature distribution and thermal stress

    Indian Academy of Sciences (India)

    P Elahi; S Morshedi

    2010-01-01

    Thermal effects of a double-end-pumped cubic Nd:YVO4 laser crystal are investigated in this paper. A detailed analysis of temperature distribution and thermal stress in cubic crystal with circular shape pumping is discussed. It has been shown that by considering the total input powers as constant, the double-end-pumped configurations with equal pump power can be considered as having a minimum thermal effect with respect to the other end-pumped configuration.

  12. Analysis of moderately thin-walled beam cross-sections by cubic isoparametric elements

    DEFF Research Database (Denmark)

    Høgsberg, Jan Becker; Krenk, Steen

    2014-01-01

    numerically by introducing a cubic-linear two-dimensional isoparametric element. The cubic interpolation of this element accurately represents quadratic shear stress variations along cross-section walls, and thus moderately thin-walled cross-sections are effectively discretized by these elements. The ability...... of this element to represent curved geometries, and to accurately determine cross-section parameters and shear stress distributions is demonstrated....

  13. Radar track segmentation with cubic splines for collision risk models in high density terminal areas

    OpenAIRE

    Cózar, J.; Saez Nieto, Francisco Javier; Ricaud Álvarez, Enrique

    2014-01-01

    This paper presents a method to segment airplane radar tracks in high density terminal areas where the air traffic follows trajectories with several changes in heading, speed and altitude. The radar tracks are modelled with different types of segments, straight lines, cubic spline function and shape preserving cubic function. The longitudinal, lateral and vertical deviations are calculated for terminal manoeuvring area scenarios. The most promising model of the radar tracks resulted from a mi...

  14. Microstructural and electrical conductivity properties of cubic zirconia doped with various amount of titania

    Directory of Open Access Journals (Sweden)

    M. Gürü

    2007-12-01

    Full Text Available Purpose: A dopant concentration higher than the optimum may reduce the number of mobile oxygen ions because of defect association causing conductivity degredation. In this study, the effect of TiO2 addition on the microstructure and electrical conductivity of cubic zirconia was investigated.Design/methodology/approach: The cubic zirconia powders with 0-10 wt% TiO2 were prepared by a colloidal processing and pressureless sintering. The effect of TiO2 addition on the microstructure and electrical conductivity of cubic zirconia was investigated. Sintered specimens were characterized by XRD, SEM and impedance spectroscopy.Findings: The experimental results showed that when the TiO2 amount was less than 5 wt %, the specimens were entirely single cubic phase; further addition of TiO2 (5 wt% or more destabilized cubic zirconia phase and caused the formation of tetragonal phase. Grain size measurements for undoped and TiO2 doped cubic zirconia specimens showed that grain size decreased with increasing TiO2 content. The electrical conductivity of TiO2 doped cubic zirconia decreased with increasing TiO2 content and increased with increasing test temperature.Research limitations/implications: The measurement of electrical conductivity is one of the important requirements for the electrolyte in solid oxide fuel cells. Generally, the ac impedance of an ionic conductor contains the contributions from grain, grain boundary and electrode-electrolyte interface at high, intermediate and low frequencies, respectively, which can be reflected in a complex plane by three successive arcs[6].Originality/value: Determination of the microstructural and electrical conductivity properties of cubic zirconia doped with various amount of titania.

  15. High-pressure phase of the cubic spinel NiMn2O4

    DEFF Research Database (Denmark)

    Åsbrink, S.; Waskowska, A.; Olsen, J. Staun;

    1998-01-01

    It has been observed that the fee spinel NiMn2O4 transforms to a tetragonal structure at about 12 GPa. The tetragonal phase does not revert to the cubic phase upon decompression and its unit-cell constants at ambient pressure are a(0)=8.65(8) and c(0)=7.88(15) Angstrom (distorted fee). Within thr......). The bulk modulus of the cubic phase is 206(4) GPa....

  16. Dynamic Cubic Instability in a 2D Q-tensor Model for Liquid Crystals

    OpenAIRE

    Iyer, Gautam; Xu, Xiang; Zarnescu, Arghir

    2014-01-01

    We consider a four-elastic-constant Landau-de Gennes energy characterizing nematic liquid crystal configurations described using the $Q$-tensor formalism. The energy contains a cubic term and is unbounded from below. We study dynamical effects produced by the presence of this cubic term by considering an $L^2$ gradient flow generated by this energy. We work in two dimensions and concentrate on understanding the relations between the physicality of the initial data and the global well-posednes...

  17. Kinetics of ray bleaching of KCl crystal with Fsub(A)(Li)-centers

    International Nuclear Information System (INIS)

    Bleaching kinetics of KCl cubic crystal with Fsub(A) (Li) centers in the two-ray excitation mode was investigated theoretically and experimentally. Possibility for using a similar system as optical lock as well as optical pulse modulator is shown. Different modes of optical system operation were investigated, time characteristics of impurity crystal bleaching were studied in a wide range of exciting ray intensities

  18. Magnetic structure map for face-centered tetragonal iron: appearance of a new collinear spin structure

    OpenAIRE

    Reith, D.; Podloucky, R.; Marsman, M; Bedolla-Velazquez, P. O.; Mohn, P.

    2013-01-01

    For face-centered cubic (fcc) and tetragonal (fct) iron a large number of magnetic configurations as a function of crystal structural parameters were studied by means of density functional theory. The stability of magnetic structures was defined by the magnetic re-orientation energy $\\Delta {E}^i_\\text{reor}$ as the difference of the total energy of configuration $i$ and that of the fcc ferromagnetic state. The Cluster Expansion technique was applied to several volumes deriving $\\Delta {E}_\\t...

  19. Face-centered-cubic titanium in Ti/Al multilayer thin films synthesized by magnetron sputtering technique

    OpenAIRE

    Rajagopalan, Ramaseshan; Dasgupta, Arup; Divakar, Ramachandran; Dash, Sitaram; Ravindran, Nithya; Saibaba, Saroja; Tyagi, Ashok Kumar; Bera, Supriya; Manna, Indranil

    2009-01-01

    Ti/Al multilayer thin films with precise thickness have been deposited using a combination of dc and rf magnetron sputtering techniques. Cross-sectional transmission electron microscopy (TEM) revealed unmixed fifteen parallel and alternate layers of Ti and Al with sharp interfaces, each measuring 27 nm and 15 nm in thickness, respectively. The Ti layer was composed of hcp and fcc phases while the Al layer was fcc. Both x-ray diffraction (XRD) and selected area electron diffraction (SAED) anal...

  20. Effect of Ti seed layers on structure of self-organized epitaxial face-centered-cubic-Ag(001) oriented nanodots

    Energy Technology Data Exchange (ETDEWEB)

    Kamiko, M.; Nose, K. [Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Suenaga, R.; Kyuno, K. [Department of Material Science, Shibaura Institute of Technology, 3-7-5 Toyosu, Koto-ku, Tokyo 135-8548 (Japan); Koo, J.-W.; Ha, J.-G. [Department of Electronic Materials Engineering, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of)

    2013-12-28

    The influence of Ti seed layers on the structure of self-organized Ag nanodots, obtained with a Ti seed-layer-assisted thermal agglomeration method, has been investigated. The samples were grown on MgO(001) single crystal substrates by RF magnetron sputter deposition. The samples were deposited at room temperature and post-annealed at 350 °C for 4 h while maintaining the chamber vacuum conditions. The results of atomic force microscopy (AFM) observations indicated that the insertion of the Ti seed layer (0.6–5.0 nm) between the MgO substrate and Ag layer promotes the agglomeration process, forming the nanodot array. Comparisons between the AFM images revealed that the size of the Ag nanodots was increased with an increase in the Ti seed layer thickness. The atomic concentration of the film surface was confirmed by X-ray photoelectron spectroscopy (XPS). The XPS result suggested that the nanodot surface mainly consisted of Ag. Moreover, X-ray diffraction results proved that the initial deposition of the Ti seed layer (0.6–5.0 nm) onto MgO(001) prior to the Ag deposition yielded high-quality fcc-Ag(001) oriented epitaxial nanodots. The optical absorbance spectra of the fabricated Ag nanodots with various Ti seed layer thicknesses were obtained in the visible light range.