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81.
Shin’ichi Konno Shigeo Kazama Maki Hiraoka Hirokazu Sakamoto Kenji Mizoguchi Hiromi Taniguchi Toshikazu Nakamura Kou Furukawa 《Journal of Low Temperature Physics》2006,142(3-4):621-624
β′-(BEDT-TTF)(TCNQ) is a compound of BEDT-TTF (=ET) and TCNQ molecules aligned orthogonally with each other, forming two-dimensional
sheets and one-dimensional columns of 1/4-filled π band, respectively. It is known that the metal-insulator transition occurs
at 330 K at ambient pressure. We have measured the electronic spin susceptibility by means of the EPR-NMR method at 50 MHz,
and the angular dependence of g-factor and line width of EPR both at Q (34 GHz) and W (94 GHz) band. We successfully confirmed
that the antiferromagnetic transition occurs in ET sheets and TCNQ columns, independently. 相似文献
82.
Processability of thermoplastic elastomer (TPE) prepared by radiation-induced grafting of methyl methacrylate (MMA) onto radiation vulcanized natural rubber latex (RVNRL) has been evaluated using a kneader and a hot roll mill at 150°C. It was found that mixing time and revolution rate (rpm) of the kneader have significantly affected the processability. The longer mixing time and the higher revolution rate result in better processability. In such processing conditions, however, the mechanical properties were found to be inferior because the molecular chain scissions occurred during the mixing. A considerable improvement of mechanical properties was obtained when the mixing was carried out without added process oils. Blends of the grafted vulcanized natural rubber latex (RVNRL-g-PMMA) and MMA grafted on unvulcanized natural rubber latex (NRL-g-PMMA) improved processability where the better processability could be achieved at a shorter mixing time and a lower revolution rate. In addition, a comparable value of mechanical properties was obtained. 相似文献
83.
Yoshiyuki Ueshima Shozo Mizoguchi Tooru Matsumiya Hiroyuki Kajioka 《Metallurgical and Materials Transactions B》1986,17(4):845-859
Solute distribution in dendrites during solidification of carbon steel was analyzed by unidirectional solidification experiments
and mathematical analysis. The characteristic of the mathematical analysis is that diffusion of solutes in solid and redistribution
of solutes at solid/liquid andδ/γ interfaces are taken into consideration. Based on the observed and calculated results, it was found that phosphorus was redistributed
fromγ-phase toδ-phase, and that manganese was slightly redistributed fromδ-phase toγ-phase. Therefore the concentrated region of phosphorus can be separated from that of manganese duringδ/γ transformation in the case of slow cooling. Moreover, it was concluded that rapid diffusion inδ-phase and the redistribution duringδ/γ transformation played an important role in the variation of the interdendritic concentrations of solutes with lower carbon
concentration. 相似文献
84.
Shigeaki Abe Yoshinori Nagoya Fumio Watari Hiroto Tachikawa 《Computational Materials Science》2011,50(9):2640-2643
The evaporation processes of water molecules adsorbed in the edge region of graphene have been investigated by means of direct MO–MD method. A large system composed of 29 water molecules and a graphene sheet (C96H24) was used as a model system. The edge carbon atom of graphene was terminated by hydrogen atom. The geometry optimization showed that the water molecules interact with the hydrogen atoms in the edge region of graphene. At low temperature (300 K), the water molecules were dissociated as water clusters from the graphene. On the other hand, in addition to the dissociation of water clusters, the isolated water molecule was also found as dissociation product at high temperature (500 K). The mechanism of water evaporation was discussed on the basis of theoretical results. 相似文献
85.
Shinoda N Hashimoto Y Takagi M Kojima F Onodera T Sugiura K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(1):24-27
A method for confirming identification of prohibited species tissue in animal feed has been developed on the basis of PCR-RFLP analysis. In Japan, to prevent the spread of BSE through animal feed, the use of animal protein in feed has been regulated. Species-specific PCR detection of prohibited species materials in feed has been used as one of a series of laboratory tests to ensure the proper implementation of the feed regulations. However, since the result of this PCR method is determined only by amplicon length, it is sometimes necessary to confirm whether or not the positive result is due to the effect of a non-specific reaction. For this purpose, DNA sequencing is the best way to confirm the test result but it is not suitable for routine analysis because of the required time and cost. In this study, we developed an easy and rapid method to confirm the species identification (mammals, ruminants and cattle) by using 4 restriction enzymes: SmlI, MboI, BlnI and Hpy188III. This PCR-RFLP method, which ensures identification of prohibited animal species in feed, is useful for enhancing the reliability of feed inspection for BSE prevention. This method will be added to the Official Methods of Feed Analysis. 相似文献
86.
In this work, we designed a new immunodevice that combines competitive immunoreactions on the microparticles, accumulation of these particles by negative dielectrophoresis (n-DEP), and their subsequent capture through hybridization among single-stranded DNAs (ssDNAs). Two widely used pesticides, atrazine and bromopropylate, were used as target molecules to test the resulting simultaneous detection system. For sensing, we prepared two different sets of microparticles: one modified with atrazine-conjugated bovine serum albumin (BSA-2d) and ssDNA-J1(up) and the other with bromopropylate-conjugated aminodextran (AD-155) and ssDNA-J2(up). The microparticles were incubated in a mixture of analyte-specific antibody and analyte at different concentrations to trap the unreacted antibodies prior to being labeled with antibodies conjugated with a fluorescence molecule. A suspension containing both types of microparticles was introduced into an n-DEP device consisting of an interdigitated microarray (IDA) electrode and channel modified with ssDNA-J1(down) and ssDNA-J2(down), which are complementary to ssDNA-J1(up) and ssDNA-J2(up), respectively. The n-DEP force generated by applying AC voltage to the IDA electrode displaced the microparticles toward the encoded areas, causing them to rapidly accumulate on the upper surfaces. Hybridization allowed us to distinguish the microparticles and sense multiple analytes by spatial recognition in the DNA-encoded areas. The fluorescence intensity of the captured particles, which depends on analyte concentrations, was measured selectively by focusing on specific areas. The strategy is advantageous for sensitivity due to the equivalent trapping efficiency by DNA hybridization and large surface area of the microparticle for immunoreactions. The rapidity and simplicity were still supported by particle manipulation. Using this concept, we detect atrazine and bromopropylate simultaneously with limits of detection (LODs) of 0.2 μg·L(-1), which covered the maximum residue level (MRL) in food samples established the European Union (EU) and Japan Ministry of Health, Labor and Welfare (MHLW). 相似文献
87.
Rapid determination of surface antigens on cells is possible by immobilization of cells accumulated by positive dielectrophoresis (p-DEP) via effective surface immunoreactions and removal of unbound cells by negative DEP (n-DEP). The DEP device for cell manipulation comprises a microfluidic channel with an upper indium tin oxide (ITO) electrode and a lower ITO microband array electrode (band electrode) modified with an antibody. Cells with the surface antigen introduced into the channel immediately accumulated on the surface of the band electrode during p-DEP generated by the application of ac voltage between the ITO electrode and the band electrode to immobilize by the specific antibody. The removal of accumulated cells to the gap region during n-DEP was used for rapid estimation of the residual cells with a specific surface antigen. We demonstrate here that human promyelocytic leukemia cells with the surface antigen CD33 can be captured on a band electrode modified with anti-CD33 antibody. The time required for the determination of the surface antigen using this compelled accumulation of cells by p-DEP and the separation of unbound cells by n-DEP is decreased to 60 s compared to that required by a cell binding assay using microtiter plates (30 min). Furthermore, the present method for a novel cell binding assay does not require pretreatment such as target labeling or washing of unbound cells and thereby enhancing throughput in the clinic and in cytobiology studies. 相似文献
88.
Crack growth characteristics of carbon nanotube-based polymer composites subjected to cyclic loading
Yu Kuronuma Yasuhide Shindo Tomo Takeda Fumio Narita 《Engineering Fracture Mechanics》2011,78(17):3102-3110
This paper presents the characterization of crack growth in carbon nanotube (CNT)-based polymer composites under fatigue loading. Fatigue crack growth tests were performed on single-edge cracked plate specimens of CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K). An elastic–plastic finite element analysis was also conducted to determine the J-integral range. The crack growth rate data were expressed in terms of the J-integral range, and the effect of nanotube addition on the fatigue crack growth behavior was examined. In addition, possible mechanisms of the crack growth in the nanocomposites are discussed based on microscopic observations of the specimen fracture surfaces. 相似文献
89.
T. Mitsuma T. Tohei N. Shibata T. Mizoguchi T. Yamamoto Y. Ikuhara 《Journal of Materials Science》2011,46(12):4162-4168
In this study, we fabricated a bicrystal of SrTiO3 containing a Σ = 9, [110]/{221} symmetric tilt grain boundary (GB) and its atomistic structure was directly observed by transmission
electron microscopy (TEM) and scanning TEM (STEM). We theoretically estimated the most stable structure by first principles
calculations, and by combining this with TEM images determined the atomistic structure of the Σ = 9 grain boundary. We found
that when the grain boundary is slightly tilted from the coincident site lattice (CSL) orientation, displacement shift complete
(DSC) dislocations are introduced at the grain boundary to accommodate the misorientation between the two adjacent crystals
while the most stable atomic structure remains unchanged. 相似文献
90.
Warat Kongkitkul Shohei Kawabe Fumio Tatsuoka Daiki Hirakawa 《Soils and Foundations》2011,51(1):11-30
A simple but automated pneumatic loading system that can control the stress and strain rates for one-dimensional (1D) compression of clay was developed. The rate-dependency of stress-strain behaviour due to the viscous property of clay was investigated by 1D compression tests on standard-size specimens by various loading methods: 1) Standard Consolidation Tests (SCTs), stepwise increasing the axial stress two times every one day; 2) ordinary Constant-Rate-of-Strain (CRS) tests at different strain rates; 3) special CRS tests including unloading and reloading cycles with different stress amplitudes at strain rates of which the absolute value was either kept constant throughout respective tests or changed at the start of reloading; and 4) special CRS tests including a number of sustained loading (SL) during otherwise primary loading or unloading or reloading at constant strain rate. Sufficiently low strain rates were employed to ensure essentially fully drained condition. The followings were found. Despite that the newly developed pneumatic loading system is rather simple, 1D compression tests following such various loading histories as above can be performed on four types of clay rather accurately. The stress-strain behaviour of clay is significantly rate-dependent, exhibiting significant creep strains at SL stages. The creep strain rate is significantly different whether SL starts during otherwise primary loading or unloading or reloading, controlled by the magnitude and sign of the initial strain rate at the start of SL. The whole observed trends of rate-dependent stress-strain behaviour can be qualitatively explained by the non-linear three-component elasto-viscoplastic model extended to cyclic loading conditions. 相似文献