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In this work, we evaluated the different energy consumption rates associated with the total frictional energy for a ball sliding on a flat surface. The energy generated by the sliding two bodies in contact is dissipated into the materials in various forms. The wear consumption energy for a steel ball against a diamond-like carbon surface was evaluated by the wear coefficient of the wear volume-energy input equation. The strain energy generated in the steel ball as a result of being made to slide under a certain load was calculated using the Hertzian theory. The chemical reaction energy was estimated based on iron oxidation. Finally, the frictional energy dissipated as heat was obtained by subtracting the wear and the strain energies from the total frictional energy. [ABSTRACT FROM AUTHOR]

Temperature rise in carbon steel (SUJ2-ASTM E52100) and stainless steel (SUS440C-ASTM 440C) balls sliding against diamond like carbon was evaluated using thermal simulation. On the premise that most of the friction energy was consumed as friction heat, the temperature distribution in the steel balls was simulated by ANSYS thermal conduction analysis using the friction energy measured by the ball on disc test. The interior temperatures of the steel balls were also monitored by a thermocouple during the tribotest. The simulation data, calibrated by the heat partition rate based on the Peclet number, were compared to the experiment data, and good accordance of both data was demonstrated. [ABSTRACT FROM AUTHOR]

ABSTRACT Dynamic sensitivities are useful to characterize time-varying systems efficiently. In metabolic reaction systems, however, analysis using these values is not so popular. This is mainly due to the following two reasons. One is that the calculation of dynamic sensitivities requires us to derive differential equations for sensitivities from those for metabolite concentrations by partial differentiation, and it is not easy for experimentalists to perform this mathematical operation. The other is that the metabolic reaction systems are mostly described by stiff differential equations, from which it may not be easy to obtain reliable numerical solutions. We have previously developed software for calculation of dynamic sensitivities ( softcads), in which one can calculate dynamic sensitivities with high accuracy by setting only differential equations for metabolite concentrations. This paper further improves the algorithm of softcads to enhance its performance. The results clearly show that regardless of the degree of stiffness, the improved softcads provides dynamic sensitivities with the super high accuracy that is comparable to the machine accuracy and also completes the calculation in a shorter time. © 2011 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study an integrated simulation of the global distribution and the radiative forcing of soil dust aerosols at the Last Glacial Maximum (LGM) is performed with an aerosol climate model, SPRINTARS. It is compared with another simulation for the present climate condition. The global total emission flux of soil dust aerosols at the LGM is simulated to be about 2.4 times as large as that in the present climate, and the simulated deposition flux is in general agreement with estimations from ice core and marine sediment samplings though it appears to be underestimated over the Antarctic. The calculated direct radiative forcings of soil dust aerosols at the LGM is close to zero at the tropopause and -0.4 W m-2 at the surface. These radiative forcings are about twice as large as those in the present climate. SPRINTARS also includes the microphysical parameterizations of the cloud-aerosol interaction both for liquid water and ice crystals, which affect the radiation budget. The positive radiative forcing from the indirect effect of soil dust aerosols is mainly caused by their properties to act as ice nuclei. This effect is simulated to be smaller (-0.9 W m-2) at the LGM than in the present. It is suggested that atmospheric dust might contribute to the cold climate during the glacial periods both through the direct and indirect effects, relative to the interglacial periods. [ABSTRACT FROM AUTHOR]

The authors previously fabricated semiconductive BaTiO[sub 3]-In composite particles. The aggregate could be used as a new positive temperature coefficients (PTC) material, which could be used in arbitrary shapes, differing from the conventional rigid PTC materials. In the composite particle, the interface between the semiconductive BaTiO[sub 3] particles and indium particles plays an important role. In this work I-V characteristics of the interface are investigated in detail. The conclusions obtained in this research are as follows. (1) The existence of indium particles at the interface between two semiconductive BaTiO[sub 3] particles lowered the electric resistance markedly. This effect was ascribed to the good plasticity and a low value of the work function of indium. (2) In-Ga eutectic liquid alloy and physically vapor-deposited indium film satisfied Ohm's law and did not form a Schottky barrier at the interface with the semiconductive BaTiO3 material. (3) Physically vapordeposited gold film formed a high electric resistance at the interface with the semiconductive BaTiO[sub 3] material. This high resistance might be caused by a Schottky barrier. [ABSTRACT FROM AUTHOR]

The electronic structure of a single pentagon in a hexagonal carbon lattice has been revealed on an atomic scale by scanning tunneling microscopy. The pentagon is located at the apex of the conical protuberance of the graphitic particle. The enhanced charge density localized at each carbon atom in the pentagon is identified, and the ringlike pattern of the (&sqrt3;x&sqrt3;)R30° superstructure of graphite is clearly observed around the pentagon. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A novel method is proposed for non-contact measurement of static electricity distribution on a surface using focused ultrasound to excite movement of the charge. The focused ultrasound is generated by controlling individually the phases of 285 airborne ultrasound transducers, and it was demonstrated local excitation could be measured. An electric field is induced by local excitation of a charged object. The electric field intensity and phase are related to the surface potential and electrical polarity of the object, respectively. It is possible to measure static electricity distribution over an entire object surface by scanning the position of the focused ultrasound. [ABSTRACT FROM AUTHOR]

Abstract: The effect of cathode particle size on cell potential was investigated using a voltage prediction method from the Coulomb potential created by the atoms of a cathode active material. LiNiO2 was selected as a typical cathode of an ordered rock salt structure. From the calculation, it was found that the voltage changes when the size becomes less than about 10nm. The voltage increased with decreasing in-plane size, and decreased with decreasing the number of layers. [Copyright &y& Elsevier]