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41.
The effect of the addition of certain low molecular weight compounds to highly crosslinked epoxy resins was investigated. The behavior which is known as antiplasticization, such as increases in modulus and yield strength and the elimination of β-transition, was observed in the highly crosslinked system as well as in the reported cases of thermoplastics—poly(vinyl chloride), bisphenol A polycarbonate, and polysulfone. Chlorinated biphenyl was found to be one of the most effective antiplasticizers examined in the present paper. However, the remarkable reduction in compressive strain at break and impact strength was not recognized for the highly antiplasticized samples. These phenomena have been interpreted on the basis of free volume concept. 相似文献
42.
Piao Y Yamashita M Kawaraichi N Asegawa R Ono H Murooka Y 《Journal of Bioscience and Bioengineering》2004,98(3):167-173
Since the chemical synthesis of vitamin B12 requires more than 70 steps, the production of vitamin B12 has been achieved by microorganism fermentation with additional brief chemical modifications. In an effort to increase the productivity of vitamin B12, we tried to express 10 genes belonging to the hem, cob and cbi gene families involved in the synthesis of vitamin B12 in Propionibacterium freudenreichii, which is a known producer of vitamin B12. In a recombinant P. freudenreichii clone that harbored the expression vector containing a cobA, cbiLF, or cbiEGH, we obtained an increase in vitamin B12 production of 1.7-, 1.9-, and 1.5-fold higher, respectively, than that in the microorganism without any cloned genes in the expression vector pPK705. The cobU and cobS genes caused a slight increase in the production of vitamin B12. Furthermore, we achieved multigene expression in P. freudenreichii. In a recombinant P. freudenreichii clone that harbored an exogenous gene, hemA, from Rhodobacter sphaeroides and endogenous hemB and cobA genes, we successfully achieved the production of about 1.7 mg/l vitamin B12, 2.2-fold higher than that produced by P. freudenreichii harboring pPK705. 相似文献
43.
Guoqing Guan Katsuki Kusakabe Haruka Ozono Masatsugu Taneda Masato Uehara Hideaki Maeda 《Journal of Materials Science》2007,42(24):10196-10202
Three-dimensionally (3D) well-ordered carbon microparticle assemblies with different particle morphologies were fabricated
by infiltration of phenolic resin solution into SiO2 inverse opal structures and subsequent carbonization. The effect of the phenolic resin solution concentration and the carbonization
temperature on the morphology of the fabricated carbon microparticles was investigated. At a carbonization temperature of
1000 °C, carbon microparticles with interlocked bridges were obtained when the concentration of phenolic resin solution is
40 wt% and hollow carbon microparticles with opened window channels were obtained at a concentration of 30–35 wt%. When the
carbonization temperature was decreased to 500 °C, carbon microparticles with interlocked bridges also were observed, even
when the phenolic resin concentration was 30 wt%. The structures and properties of the carbon microparticles and their assemblies
were characterized using SEM, XRD, and N2 adsorption. 相似文献
44.
Ryo Toda Yuki Matsushita Mitsunori Hieda Taku Matsushita Nobuo Wada 《Journal of Low Temperature Physics》2007,148(5-6):785-790
We have measured the heat capacity of 3He adsorbed on three-dimensionally connected nanopores, 2.7 nm in diameter, preplated with about 1.3 atomic layers of 4He. At low coverages of 3He, the 3He heat capacity is roughly constant at the measured temperatures between 0.1 and 1 K. Its molar heat capacity is on the order
of the gas constant R, between 1.1R and 1.8R. This suggests a Boltzmann gas state of the adsorbed 3He. At high coverages, the heat capacity is likely approaching linear in T at low temperatures, which suggests a degenerate state at further lower temperatures. 相似文献
45.
Takashi Kojima Yasuki Mori Masahiro Kamiya Ryo Sasai Hideaki Itoh 《Journal of Materials Science》2007,42(15):6056-6061
Capability of the recycling of high strength and high fracture toughness yttria-stabilized tetragonal zirconia polycrystalline
(Y-TZP) sintered body utilizing “low-temperature annealing degradation” phenomenon was investigated. Hydrothermal treatment
was employed to induce the phase transformation from tetragonal to monoclinic zirconia and to disintegrate the Y-TZP sintered
body. 3 mol% Y2O3–ZrO2 specimens sintered at 1,550 °C and more were disintegrated without leaving the original appearances when the treatment temperature
was between 200 °C and 400 °C. The size of the disintegrated fragments of Y-TZP sintered body was much affected by hydrothermal
treatment conditions. Only with hydrothermal treatment and simple ball milling, the sintered body was pulverized into the
primary particle level. This technique is expected to apply to a sustainable recycling system for the zirconia ceramics, which
restrains an energy consumption compared to crushing zirconia using mechanical procedures. 相似文献
46.
Ryo Sakurai Shingo Ohno Shin‐ichi Kita Yoshitomo Masuda Reiji Hattori 《Journal of the Society for Information Display》2007,15(2):127-131
Abstract— Color displays and flexible displays that use electronic liquid powder have been developed. Novel types of color displays using either a colored powder or a color filter are discussed. We have also developed a flexible display with low‐cost substrate films with a high‐throughput roll‐to‐roll manufacturing method. These technologies enable a QR‐LPD to be widely used as an electronic‐paper display. 相似文献
47.
Kyohei Terao Chihiro Masuda Ryo Inukai Murat Gel Hidehiro Oana Masao Washizu Takaaki Suzuki Hidekuni Takao Fusao Shimokawa Fumikazu Oohira 《IET nanobiotechnology / IET》2016,10(3):124
Optical tweezers are powerful tools for manipulating single DNA molecules using fluorescence microscopy, particularly in nanotechnology‐based DNA analysis. We previously proposed a manipulation technique using microstructures driven by optical tweezers that allows the handling of single giant DNA molecules of millimetre length that cannot be manipulated by conventional techniques. To further develop this technique, the authors characterised the microstructures quantitatively from the view point of fabrication and efficiency of DNA manipulation under a fluorescence microscope. The success rate and precision of the fabrications were evaluated. The results indicate that the microstructures are obtained in an aqueous solution with a precision ∼50 nm at concentrations in the order of 106 particles/ml. The visibility of these microstructures under a fluorescence microscope was also characterised, along with the elucidation of the fabrication parameters needed to fine tune visibility. Manipulating yeast chromosomal DNA molecules with the microstructures illustrated the relationship between the efficiency of manipulation and the geometrical shape of the microstructure. This report provides the guidelines for designing microstructures used in single DNA molecule analysis based on on‐site DNA manipulation, and is expected to broaden the applications of this technique in the future.Inspec keywords: DNA, molecular biophysics, fluorescence, optical microscopy, radiation pressure, biological techniquesOther keywords: optically driven microstructures, single DNA molecule analysis, fluorescence microscopy, optical tweezers, nanotechnology‐based DNA analysis, manipulation technique, aqueous solution, fine tune visibility, yeast chromosomal DNA molecules, geometrical shape, on‐site DNA manipulation 相似文献
48.
Spectral mixture analysis for bi-sensor wetland mapping using Landsat TM and Terra MODIS data 总被引:2,自引:0,他引:2
Spatial and temporal resolution is essential for understanding the spatial and temporal characteristics and dynamics of wetland ecosystems. However, single satellite imagery with both high spatial resolution and high temporal frequency is currently unavailable. Instead, the development of a bi-sensor monitoring technique utilizing spatial details of middle-to-high resolution data and temporal details of coarse spatial resolution data is highly desirable. For the initial work on our time-series bi-sensor wetland mapping, the applicability of multiple endmember spectral mixture analysis (MESMA) using single-date bi-sensor imagery with different orbiting periods was investigated. Landsat-5 Thematic Mapper (TM) and Terra Moderate Resolution Image Spectrometer (MODIS) data were utilized in the Poyang Lake area in China and the Great Salt Lake area in the USA to examine three decisive elements in utilizing MESMA: (1) the method of optimal endmember selection; (2) the threshold between two- and three-endmember models; and (3) the treatment of shade fractions. As a result, we found that (1) the number of spectra for an endmember spectrum similar to other endmember spectra meeting the modelling restrictions of maximum and minimum land-cover fractions and root mean square error (RMSE) within a class (In_CoB), the number of spectra for an endmember spectrum similar to other endmember spectra meeting the modelling restrictions outside of a class (Out_CoB), the ratio of In_CoB to Out_CoB multiplied by the inverse number of spectra within the class (CoBI) and the endmember average RMSE (EAR) were optimal endmember selection methods for the TM maps, whereas CoBI, EAR and minimum average spectral angle (MASA) were optimal endmember selection methods for the MODIS maps; (2) the MODIS maps were more sensitive to change in the two- and three-endmember modelling thresholds than the TM maps; and (3) the addition of shade fractions to dark water fractions were an appropriate shade treatment. This research demonstrated how MESMA can be applied for multi-scale mapping of wetland ecosystems, how the difference in observation dates between the TM and MODIS data affects the agreement in land-cover fractions and how spectral similarity between dark water and shade affects the agreement in land-cover fractions. 相似文献
49.
A wind turbine generator (WTG) system's output is not constant and fluctuates depending on wind conditions. Fluctuating power causes frequency deviations and adverse effects to an isolated power system when large output power from WTG systems is penetrated in the power system. This paper presents an output power control methodology of a WTG for frequency control using a load power estimator. The load power is estimated by a disturbance observer, and the output power command of the WTG is determined according to the estimated load. Besides, the WTG can also be controlled during wind turbulence since the output power command is determined by considering wind conditions. The reduction of the power system frequency deviation by using the WTG can be achieved by the proposed method. The effectiveness of the proposed method is validated by numerical simulations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
50.
Kosuke Aiuchi Ryo Moriyama Shohei Takeda Shunji Kitada Masaki Onozaki Yukuo Katayama 《Fuel Processing Technology》2007
A pre-heating vaporization technology of coal water slurry, CWS, was developed to increase the efficiency of coal gasification with the reduction of oxygen consumption. A CWS pre-heating experimental unit having a capacity of 2.0 tons-coal/day was manufactured. After the CWS was heated to 573 K at about 10 MPa, water in CWS was continuously vaporized in a tube of which the diameter increased gradually (2–10 mm I.D.), and dry coal particles with steam were atomized and fed to a vessel. No aggregation of coal particles was observed in the atomized samples. The temperature and the pressure distributions of the fluid were calculated with empirical heat transfer and pressure drop correlations. The calculated results well corresponded to the experimental data measured in some test points. Using the calculation model, a large scale apparatus of 100 tons-coal/day was designed using KNO3 + NaNO2 + NaNO3 molten salt as a heating medium. 相似文献