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71.
With the objective of developing an odorless biodegradation process for dimethyl sulfoxide (DMSO), Hyphomicrobium sp. WU-OM3 was isolated. During the cultivation of strain WU-OM3 cells with 20 mM dimethyl sulfone (DMSO2) as the sole carbon source, DMSO2 was completely consumed within 48 h and sulfate ion accumulated in the culture broth. Methanesulfonate was also detected as an intermediate of DMSO2 degradation. By combining the DMSO-oxidizing microorganism and strain WU-OM3 cells, 0.64 mM (50 mg/l) DMSO was degraded to sulfate ion with 80% molar conversion ratio.  相似文献   
72.
The purpose of this research was to investigate the ice growth of a single crystal in three dimensions. Three-dimensional pattern of ice crystal growth in supercooled water was observed using Mach–Zehnder spectro-interferometer. Temperature was varied from −0.3 to −1.6 °C. It was found that the ice crystal began to grow as a single crystal at the tip of the capillary tube and propagated freely in supercooled water. Time variation of the shape of dendrite on a–c plane was obtained. It was found that half parabola fits the shape very closely, and the coefficient of squared term, a, of a quadratic function was calculated. The coefficient, a varied in time but at quasi steady state it was found to be depending mostly upon the degree of supercooling. Furthermore, the growth velocity in c-axis at the flat surface was calculated from the thickness measured. It was found that the velocity in c-axis is independent of the degree of supercooling but depends upon time, in other words, the thickness in c-axis.  相似文献   
73.
74.
Transparent hexagonal BN films were deposited onto copper substrates from the reactant gas BCl3-NH3-H2 at temperatures in the range 250–700°C. The lowest deposition temperature of the films was about 250°C. The films deposited at temperatures below 450°C were unstable in moist atmosphere and devitrified; a 20%–30% decrease in weight was observed when these films were heated above 600°C in an argon atmosphere. In contrast, the films deposited at temperatures above 600°C were very stable, decreased in weight by 1%–2% on heating and were stable in air at temperatures below 750°C.  相似文献   
75.
Kurihara M  Ikeda K  Izawa Y  Deguchi Y  Tarui H 《Applied optics》2003,42(30):6159-6165
A laser-induced breakdown spectroscopy (LIBS) technique has been applied for detection of unburned carbon in fly ash, and an automated LIBS unit has been developed and applied in a 1000-MW pulverized-coal-fired power plant for real-time measurement, specifically of unburned carbon in fly ash. Good agreement was found between measurement results from the LIBS method and those from the conventional method (Japanese Industrial Standard 8815), with a standard deviation of 0.27%. This result confirms that the measurement of unburned carbon in fly ash by use of LIBS is sufficiently accurate for boiler control. Measurements taken by this apparatus were also integrated into a boiler-control system with the objective of achieving optimal and stable combustion. By control of the rotating speed of a mill rotary separator relative to measured unburned-carbon content, it has been demonstrated that boiler control is possible in an optimized manner by use of the value of the unburned-carbon content of fly ash.  相似文献   
76.
In this paper, the authors propose a method that incorporates mechanisms for handling ambiguity in speech and the ability of humans to create associations, and for formulating conversations based on rule base knowledge and common knowledge. Go beyond the level that can be achieved, using only conventional natural language processing and vast repositories of sample patterns. In this paper, the authors propose a method for computer conversation sentences generated using newspaper headlines as an example of how the common knowledge and associative ability are applied.  相似文献   
77.
An analytical and experimental investigation was performed on a heat removal process of the thermal energy storage (TES) capsule, using gelled Glauber's salt. Transient heat flux at the capsule wall was measured for various cooling conditions. In cases where the initial temperature was lower than the saturation temperature of the phase change material (PCM), numerical analyses were performed, approximating the process by a relaxation phenomenon where crystals grew around crystal nuclei. The results of the numerical solution agreed very well with the experimental results.  相似文献   
78.
We discuss the general theoretical arguments advanced earlier for the T=0 global phase diagram of antiferromagnetic Kondo lattice systems, distinguishing between the established and the conjectured. In addition to the well-known phase of a paramagnetic metal with a “large” Fermi surface (PL), there is also an antiferromagnetic phase with a “small” Fermi surface (AFS). We provide the details of the derivation of a quantum non-linear sigma-model (QNLσM) representation of the Kondo lattice Hamiltonian, which leads to an effective field theory containing both low-energy fermions in the vicinity of a Fermi surface and low-energy bosons near zero momentum. An asymptotically exact analysis of this effective field theory is made possible through the development of a renormalization group procedure for mixed fermion-boson systems. Considerations on how to connect the AFS and PL phases lead to a global phase diagram, which not only puts into perspective the theory of local quantum criticality for antiferromagnetic heavy fermion metals, but also provides the basis to understand the surprising recent experiments in chemically-doped as well as pressurized YbRh2Si2. We point out that the AFS phase still occurs for the case of an equal number of spin-1/2 local moments and conduction electrons. This observation raises the prospect for a global phase diagram of heavy fermion systems in the Kondo-insulator regime. Finally, we discuss the connection between the Kondo breakdown physics discussed here for the Kondo lattice systems and the non-Fermi liquid behavior recently studied from a holographic perspective.  相似文献   
79.
Vapor-grown carbon micro-coils were oxidized under a low O2 flow-rate for introducing oxygen-containing functional groups on the surface. The surface characteristics were then examined. The O1s/C1s intensity ratios of the XPS spectra measured on the surface increased on using the oxidation treatment. The maximum O1s/C1s ratio of 11.4 at.% was obtained under the following conditions: (a) the flow-rate of the mixed gas of O2+Ar (O2/Ar=1/10) was 82.5 sccm; (b) the oxidation temperature was 600°C; and (c) the treatment time was 30 min. The maximum O1s/C1s ratio is about 3.5 times that of the source carbon coils. The specific surface area significantly increased due to the oxidation treatment and attained a maximum value of 1050 m2 g−1, which is about 10 times that of the source carbon coils. As the specific surface area increased, the surface morphology of the carbon coils became more complicated on a nanometer scale.  相似文献   
80.
The solubility of fullerene C60 in toluene was measured at temperatures between 278.2 and 308.2 K and pressures up to 340 MPa, and also at temperatures between 258.2 and 298.2 K under atmospheric pressure. The solubility increased with increasing pressure, and then decreased with a sharp maximum, suggesting a transition between solid phases. A thermodynamic analysis of the solubility supported the proposal of Korobov, et al. that the two solids correspond to C60 (fcc) and C60 · 2 (toluene) solvate. The solubility enhancement of C60 by pressure in a low-pressure region is an unusual phenomenon when compared with the decrease in solubility of nonpolar molecular solids generally observed with rises in pressure.  相似文献   
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