On the basis of results obtained in a previous paper by the moment method the thermodynamic quantities of the inert gas crystals are calculated. The obtained results are compared with the experimental data and with the ones of other... more
On the basis of results obtained in a previous paper by the moment method the thermodynamic quantities of the inert gas crystals are calculated. The obtained results are compared with the experimental data and with the ones of other authors.Auf der Grundlage der in einer früheren Arbeit mit Hilfe der Momenten-Methode erhaltenen Ergebnisse werden die thermodynamischen Größen für Inertgas-Kristalle berechnet. Die erhaltenen Ergebnisse werden mit den experimentellen Daten und den Resultaten anderer Autoren verglichen.
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In this paper, the energy dissipation in small-diameter Quartz Crystal Microbalance (QCM) was experimentally studied for ultra-high sensitive gravimetric measurements. Newly developed deep reactive ion etching technology for smooth... more
In this paper, the energy dissipation in small-diameter Quartz Crystal Microbalance (QCM) was experimentally studied for ultra-high sensitive gravimetric measurements. Newly developed deep reactive ion etching technology for smooth surface glass etching was used for the fabrication of small-diameter QCM. Minimum average surface roughness is 2.3 nm for an etching with SF6/Xe (=1/1) gases and 1.8 nm for SF6/Ar (=1/4) gases at a pressure of 0.2 Pa with a self-bias voltage of -390 V. The diameters of fabricated QCM were 0.2-1.0mm and their thickness was in the range of 6-82μm. The Q-factor of the fabricated QCM increases exponentially from 2000 to 10000 as the thickness decreases due to the decrease of supporting loss. Interestingly, the increases of Q-factor deviate from simple exponential function and show a maximum peak of the Q-factor (30000).
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By the moment method established previously on the basis of the statistical mechanics, the thermodynamic properties of a strongly anharmonic crystal with the f.c.c. structure are considered. The analytic expressions for the thermodynamic... more
By the moment method established previously on the basis of the statistical mechanics, the thermodynamic properties of a strongly anharmonic crystal with the f.c.c. structure are considered. The analytic expressions for the thermodynamic quantities as the thermal expansion coefficient, the specific heats Cv and Cp, the isothermal and adiabatic compressibilities, etc. are obtained.Mit einer früher abgeleiteten Momentenmethode auf der Grundlage der statistischen Mechanik werden die thermodynamischen Eigenschaften eines stark anharmonischen Kristalls mit k.f.z.-Struktur untersucht. Die analytischen Ausdrücke für die thermodynamischen Größen, wie thermischer Ausdehnungskoeffizient, spezifische Wärme, Cv und Cp, die isothermen und adiabatischen Kompressionsvermögen usw. werden erhalten.
Research Interests: Engineering, Materials Engineering, Chemical Engineering, Mathematical Physics, Condensed Matter Physics, and 25 moreQuantum Physics, Thermodynamics, Analytical Chemistry, Technology, Back Propagation, Nanotechnology, Nuclear Materials, Neural Network, Mathematical Sciences, Density Functional Theory, Gibbs Free Energy, Physical sciences, Bulk Modulus, Free Energy, Transfer Function, Temperature Dependence, CHEMICAL SCIENCES, Heat Capacity, Ozone, Ozone layer depletion, Specific Heat, Experimental Measurement, Thermodynamic Stability, Artificial Neural Network, and Thermodynamic Properties
By the momentum method established in the preceding papers the thermodynamic properties of strongly anharmonic crystals are considered with face-centred cubic structure being under action of pressure. In the application properties as the... more
By the momentum method established in the preceding papers the thermodynamic properties of strongly anharmonic crystals are considered with face-centred cubic structure being under action of pressure. In the application properties as the thermal expansion coefficient, the specific heats cv and cp etc. at various pressures are calculated numerically for the inert gas solids and compared with experimental data.Mit der in früheren Arbeiten angegebenen Momentenmethode werden die thermodynamischen Eigenschaften von stark anharmonischen Kristallen mit kubischflächenzentrierter Struktur unter Druckeinwirkung untersucht. In Anwendung werden Eigenschaften, wie thermischer Ausdehnungs-koeffizient, spezifische Wärmen cv und cp usw., bei verschiedenen Drücken für Inertgasfestkörper numerisch berechnet und mit experimentellen Werten verglichen.
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Research Interests: Materials Engineering, Physics, Condensed Matter Physics, Thermodynamics, High Pressure, and 13 moreNanotechnology, Mathematical Sciences, Si, Physical sciences, High Temperature, Low Temperature, Moment method, Specific Heat, Thermal Expansion, Thermodynamic Properties, Hydrostatic Pressure, Negative thermal expansion, and Cumulant
Research Interests: Engineering, Materials Engineering, Chemical Engineering, Mathematical Physics, Condensed Matter Physics, and 25 moreQuantum Physics, Thermodynamics, Analytical Chemistry, Technology, Back Propagation, Nanotechnology, Nuclear Materials, Neural Network, Mathematical Sciences, Density Functional Theory, Gibbs Free Energy, Physical sciences, Bulk Modulus, Free Energy, Transfer Function, Temperature Dependence, CHEMICAL SCIENCES, Heat Capacity, Ozone, Ozone layer depletion, Specific Heat, Experimental Measurement, Thermodynamic Stability, Artificial Neural Network, and Thermodynamic Properties
This paper presents the kinematic analysis of a new 6-DOF haptic interface and control system analysis for the tele-operation of 6-DOF serial robot. The haptic interface consists of two 3-DOF parallel structures connected with a steering... more
This paper presents the kinematic analysis of a new 6-DOF haptic interface and control system analysis for the tele-operation of 6-DOF serial robot. The haptic interface consists of two 3-DOF parallel structures connected with a steering handle. The design satisfies requirements of low mass moment of inertia, quick motion, big rotation, and large applied torques. Kinematics for position and differential motion are developed for the 6-DOF haptic interface. Tele-operation of a 6-DOF serial manipulator using this haptic interface is demonstrated. Experiment results provide comparison of trajectories and forces/torques between 6-DOF haptic interface and 6-DOF serial robot on the Cartesian space.
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We report a case of perforation caused by cutting balloon angioplasty of in-stent restenosis in a saphenous vein coronary bypass graft. This was complicated by a subepicardial hematoma leading to avulsion of the penetrating arteries and... more
We report a case of perforation caused by cutting balloon angioplasty of in-stent restenosis in a saphenous vein coronary bypass graft. This was complicated by a subepicardial hematoma leading to avulsion of the penetrating arteries and cardiogenic shock. Despite surgical evacuation and percutaneous left ventricular assist-device support, death ensued. Catheter Cardiovasc Interv 2005;64:163–168. © 2005 Wiley-Liss, Inc.
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The self-diffusion in metals is studied using the moment method in the statistical dynamics including the anharmonicity effects of lattice vibrations. The Gibbs free energy of a metal lattice containing thermal vacancies is derived using... more
The self-diffusion in metals is studied using the moment method in the statistical dynamics including the anharmonicity effects of lattice vibrations. The Gibbs free energy of a metal lattice containing thermal vacancies is derived using the fourth order moment approximation. The interaction energies between the atoms in metals are estimated by using the effective pair potentials. The activation energy Q and pre-exponential factor D0 of the self-diffusion coefficient are given in closed forms. The activation energy Q and pre-exponential D0 values are calculated for Fe, Ag, Ta, and W metals at high temperature region near the melting temperature as well as at low (liquid Helium) temperatures, and they are shown to be in good agreement with the experimental results.
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We show that the hcp (alpha)-->bcc(beta) structural phase transformation of titanium occurs via anharmonicity effect of thermal lattice vibrations. The full-potential linear muffin-tin orbital method in the local density approximation... more
We show that the hcp (alpha)-->bcc(beta) structural phase transformation of titanium occurs via anharmonicity effect of thermal lattice vibrations. The full-potential linear muffin-tin orbital method in the local density approximation with the generalized gradient correction is used to derive the embedded atom potential for Ti, which allows us the analytic and realistic calculations of the thermodynamic quantities. We also discuss the similar phase transformation but slightly different mechanism occurring in zirconium in terms of the anharmonicity of thermal lattice vibrations.
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The thermodynamic quantities of metals and alloys are studied using the moment method in the quantum statistical mechanics, going beyond the quasi-harmonic (QH) approximations. Including the power moments of the atomic displacements up to... more
The thermodynamic quantities of metals and alloys are studied using the moment method in the quantum statistical mechanics, going beyond the quasi-harmonic (QH) approximations. Including the power moments of the atomic displacements up to the fourth order, the free energies and the related thermodynamic quantities are derived explicitly in closed analytic forms. The configurational entropy term is taken into account by coupling the moment expansion scheme with the cluster variation method (CVM). The energetics of the binary (TaW) alloys are treated within the framework of the first-principles tight-binding linear muffin-tin orbital (TB-LMTO) method coupled to the coherent potential approximation (CPA) and generalized perturbation method (GPM). The equilibrium phase diagrams are calculated for the refractory Ta-W bcc alloys.
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Research Interests:
The crack nucleation and propagation processes in nanoscale materials are studied using the ab initio constraint molecular dynamics method and the lattice Green’s function method. We investigate the strength and fracture behaviors of... more
The crack nucleation and propagation processes in nanoscale materials are studied using the ab initio constraint molecular dynamics method and the lattice Green’s function method. We investigate the strength and fracture behaviors of carbon related nanoscale materials, especially the graphen sheets in comparison with those of carbon nanotubes. The linear elastic parameters, non-linear elastic instabilities, thermal lattice expansion and fracture behaviors are studied in detail. We will show that the thermodynamic and strength properties of the nanoscale materials exhibit characteristic features and they are different from those of the corresponding bulk materials.
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Research Interests:
The Ginzburg-Landau functional for a two-gap superconductor is derived within the weak-coupling BCS model. The two-gap Ginzburg-Landau theory is, then, applied to investigate various magnetic properties of MgB2 including an upturn... more
The Ginzburg-Landau functional for a two-gap superconductor is derived within the weak-coupling BCS model. The two-gap Ginzburg-Landau theory is, then, applied to investigate various magnetic properties of MgB2 including an upturn temperature dependence of the transverse upper critical field and a core structure of an isolated vortex. Orientation of vortex lattice relative to crystallographic axes is studied for magnetic fields parallel to the c-axis. A peculiar 30-degree rotation of the vortex lattice with increasing strength of an applied field observed by neutron scattering is attributed to the multi-gap nature of superconductivity in MgB2.