The Thermal Conductivity and Thermal Diffusivity of Liquid n-Alkanes: C n H2n+2 (n=5 to 10) and Toluene

Experimental values of the thermal conductivity and the thermal diffusivity of six pure liquid n-alkanes (C _n H_2n+2; n=5 to 10) and toluene are presented in the temperature range of –20 to 70°C under atmospheric or saturation pressure. Measurements were made with the transient hot-wire method, and in the analysis, the temperatures T and T (associated with both and ) were used. In the present work, the values of thermal diffusivity were corrected by the factors k _f (=1.0076 to 0.9892) for data sets obtained with different configurations of the experiment, in which the factors were determined by reference to the thermal diffusivity of n-heptane [= _s/(c _p )_s] at 298.15 K calculated from the volumic heat capacity (c _p )_s as a reference material for heat capacity and the experimentally obtained thermal conductivity _s. The uncertainty of the data is estimated to be 0.48% for the thermal conductivity (absolutely measured) and about 1.8% for the thermal diffusivity (with a coverage factor of k _p =2; p=95%).     

Evaluation of crystallinity in TiO2 films with mixed structures grown on MgO (001) substrates by argon-ion beam sputtering based on infrared reflection-absorption spectra

TiO2 films with thicknesses (d) above 15 nm were grown on optically polished surfaces of MgO (001) substrates held at 400 degrees C by sputtering a Ti target with an argon-ion beam when the partial pressure of O2 was kept at 1.1 x 10(-2) Pa. X-ray diffraction patterns show that TiO2 films with d < 56 nm are composed of an a-axis anatase-type structure, whereas those with d > 56 nm are composed of a mixture of phases with the c-axis parallel to the film surface. The thickness dependence of the infrared reflection-absorption spectra shows that TiO2 films with d < 56 nm are composed of both anatase and amorphous phases, whereas those with d > 56 nm are composed of anatase, rutile, and amorphous phases. The crystallinity in TiO2 films is also evaluated from the infrared reflection-absorption spectra by comparison of the observed and the calculated results determined from the dielectric function of anisotropic TiO2 bulk single crystal.     

Fabrication of optics by use of plasma chemical vaporization machining with a pipe electrode

We figure optical surfaces by plasma chemical vaporization machining (CVM) with a pipe electrode, in which an rf plasma generated at the electrode tip under approximately atmospheric pressure moves over the surfaces. We propose a shaping method in which the movement of plasma on the surfaces can be determined. Flat and aspheric surfaces are successfully figured with the desired peak-to-valley shape accuracy of 0.1 microm. The root-mean-square roughness of the resultant surfaces is at the subnanometer level. These results confirm that the plasma CVM and the shaping method have the capability to fabricate optics with high accuracy.     

In vitro construction and screening of a Burkholderia cepacia lipase library using single-molecule PCR and cell-free protein synthesis

A mutant library of Burkholderia cepacia lipase KWI-56 was constructed on microplates by a cell-free process and tested with a chromogenic assay. This high-throughput construction system can be used to screen mutant proteins based on their catalytic activity.     

Analytical tool development for coarse break-up of a molten jet in a deep water pool

A computer code JASMINE-pre was developed for the prediction of premixing conditions of fuel–coolant interactions and debris bed formation behavior relevant to severe accidents of light water reactors. In JASMINE-pre code, a melt model which consists of three components of sub-models for melt jet, melt particles and melt pool, is coupled with a two-phase flow model derived from ACE-3D code developed at JAERI. The melt jet and melt pool models are one-dimensional representations of a molten core stream falling into a water pool and a continuous melt body agglomerated on the bottom, respectively. The melt particles generated by the melt jet break-up are modeled based on a Lagrangian grouped particle concept. Additionally, a simplified model pmjet was developed which considers only steady state break-up of the melt jet, cooling and settlement of particles in a stationary water pool. The FARO corium quenching experiments with a saturation temperature water pool and a subcooled water pool were simulated with JASMINE-pre and pmjet. JASMINE-pre reproduced the pressurization and fragmentation behavior observed in the experiments with a reasonable accuracy. Also, the influences of model parameters on the pressurization and fragmentation were examined. The calculation results showed a quasi-steady state phase of melt jet break-up during which the amount of molten mass contained in the premixture was kept almost constant, and the steady state molten premixed masses evaluated by JASMINE-pre and pmjet agreed well.     

基于Isabelle的证明信息系统设计

Isabelle定理证明器中的证明步骤和证明状态是非常具有参考价值的证明信息。然而目前没有工具可以有效管理这些信息。本文给出一个基于Isabelle的信息系统设计方案。利用该系统的实现,用户可以提取、保存和搜索这两种证明信息。     

Photo-Induced Effect of the Electron-Spin Resonance on the Charge-Ordered State in Pr0.65Ca0.35MnO3

Electron-spin resonance (ESR) for the charge-ordered state in well-characterized Pr_0.65Ca_0.35MnO₃ exhibited significant change of both the absorption profile and the effective spin susceptibility upon injection of laser light with photon energy of 1.17 eV provided by Nd-YAG laser. The increase of the effective spin susceptibility was clearly found out thanks to the injection of photons in the temperature range 90 K–80 K, which is below the transition temperature from the antiferromagnetic charge ordered state to the canted antiferromagnetic spin alternation state, T _CAF125 K. The temperature dependence of the change of the ESR profile excludes the possibility of heating by laser light. The present result suggests that a kind of photo-induced insulator–metal transition may occur due to propagation of the delocalized carriers via probable double exchange interaction in the charge-ordering collapsed state created by the injection of photons.     

Electron Spin Resonance in Pr0.65Ca0.35MnO3

The magnetic behavior of the distorted perovskite manganese, Pr_0.65Ca_0.35MnO₃ was studied by X-band electron spin resonance for powder samples. We observed the onset of the charge-ordered state at T _CO215 K, the antiferromagnetic transition with the peak of the ESR linewidth, H _p–p at T _AF180 K and the canted antiferromagnetic transition at T _CAF125 K associated with the abrupt increase of both the effective magnetization and H _p–p . Below 90 K, the absorption intensity profile becomes weakened with decreasing temperature suggesting the existence of some kind of magnetic disorder below 90 K, which is responsible for a part of evidence of the existence of the spin-glass state as has been proposed by Yoshizawa et al., Phys. Rev. B 52, 1689 (1996).     

Water mist formation in vapor-mist dielectrics and its effect

It has been proposed that vapor-mist dielectrics in which mixing liquid droplets such as tetrachloroethlene in a gas have the ability of increasing flashover, impulse voltage, and of suppressing partial discharge. Vapor-mist methods have been performed on other materials and the effect of the mist can also be obtained on benzene, hexane, and even water as general materials. Although these studies have been carried out, neither the discharge mechanism on vapor-mist nor the reason for the increase of the discharge voltage is understood fully because the mist is of various sizes. On the other hand, agglomeration of water molecules can be studied with the FR-IR method, and are classified into monomer, dimer, trimer (including polymer). Water gives mist stats which are significant in discussing effects. This paper describes states of water mist and their effect under nonuniform field with positive and negative polarities. Water mist in vapor exists as dimer and trimer, and their amount decreases with the reduction of temperature. These mists have no effect on discharge suppression. However, when the mists are formed by space charges, the inception voltage is increased by these mists in the negative polarity.     

Fatigue behavior of carburized steel with internal oxides and nonmartensitic microstructure near the surface

The characteristic fatigue behavior of carburized and quenched steel with internal oxides and non-martensitic microstructure near the surface was presented through rotating bending fatigue test. The S-N diagram revealed two knees and the specimens continued to fail over 10⁷ stress cycles. The fatigue limit could not be obtained even at 10⁸ stress cycles. The test results were compared to those for the specimens without surface structure anomalies to show the effect of structure anomalies on the fatigue behavior of carburized steel.