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71.
72.
We report a method that uses near-infrared spectroscopy and multivariate analysis to measure the temperature of turbid aqueous solutions. The measurement principle is based on the fact that the peak wavelength of the water absorption band, with its center near 1440 nm, shifts with changes in temperature. This principle was used to measure the temperatures of 1 mm thick samples of aqueous solutions containing Intralipid (2%), which are often used as optical phantoms for biological tissues due to similar scattering characteristics. Temperatures of pure water and aqueous solutions containing glucose (100 mg/ml and 200 mg/ml) were also measured for comparison. For the turbid Intralipid solutions, the absorbance spectrum varied irregularly with time due to the change in scattering characteristics. However, by making use of the difference between the absorbance at 1412 nm and the temperature-independent absorbance at 1440 nm, we obtained SEPs (standard error of prediction) of 0.3 degrees C and 0.2 degrees C by univariate linear regression and partial least squares regression, respectively. These accuracies were almost the same as those for the transparent samples (pure water and glucose solution). 相似文献
73.
A thermally activated model for evaluating the tensile yield strain of pristine single-walled carbon nanotubes (SWCNTs) is established. Using a parabolic function to accurately describe the dependence of stress on strain, we derive a yield function relating the yield strain to temperature, strain rate and tube length. The activation energy and activation area are then determined from the MD results of the tensile yield strain as a function of temperature. We find that the activation energies for armchair SWCNTs range from 7.18 to 11.94 eV, depending on the radius of SWCNTs. Analyses of activation area and MD results reveal that the nucleation of a critical defect, which leads to the failure of SWCNTs, grows from a single bond size at 300 K to almost twice the size at 2100 K. On the basis of activation parameters, our model can be used to predict the yield strain of SWCNTs under experimental conditions. 相似文献
74.
Hirotsugu Takizawa Naoto HazeKeisuke Okamoto Kyota UhedaTadashi Endo 《Materials Research Bulletin》2002,37(1):113-121
Iron-doped β-rhombohedral boron was synthesized by 28 GHz microwave irradiation on a powder mixture of iron and β-boron. β-Boron strongly absorbs 28 GHz microwaves, and this strong coupling with microwave energy can be used to promote a reaction with iron dopant. The powder mixture was heated to 1800°C within 2 min by microwave irradiation, resulting in the formation of β-rhombohedral boron interstitially doped with iron. The reaction proceeded rapidly without accompanying grain growth. The XRD analysis and the electrical conductivity measurements revealed successful incorporation of iron into two doping sites of β-boron. 相似文献
75.
Nosaka H. Sano E. Ishii K. Ida M. Kurishima K. Yamahata S. Shibata T. Fukuyama H. Yoneyama M. Enoki T. Muraguchi M. 《Solid-State Circuits, IEEE Journal of》2004,39(8):1361-1365
We describe a 40-Gbit/s-class clock and data recovery (CDR) circuit with an extremely wide pull-in range. A Darlington-type voltage-controlled oscillator (VCO) is newly designed to cover the STM-256/OC-768 full-rate-clock frequencies with a wide frequency margin. We also describe a new lock detector using an exclusive-NOR gate. The CDR IC was fabricated using InP/InGaAs HBTs. Error-free operation and wide eye opening were confirmed for 40-, 43-, and 45-Gbit/s PRBS with a word length of 2/sup 31/ - 1. We attached a frequency search and phase control (FSPC) circuit to the chip as a new frequency acquisition aid, and this allows the CDR circuit to pull in throughout a 39-45-Gbit/s range. The peak-to-peak and rms jitter of the recovered clock were 3.6 and 0.48 ps, respectively. 相似文献
76.
T Takaya K Maeda H Fukuyama K Watanabe M Takiguchi 《Canadian Metallurgical Quarterly》1997,46(6):764-769
To determine the optimum dose of lidocaine administered in the trachea prior to endotracheal intubation, we divided 102 surgical patients 3-5 years of age into 3 groups, i.e., group 1; 1 mg.kg-1 was sprayed in the trachea, group 2; 2 mg.kg-1 was sprayed in the trachea, group 3; 1 mg.kg-1 was sprayed in the trachea, and 1 mg.kg-1 in the pharynx and the oral cavity simultaneously. The venous serum concentration of lidocaine was measured two times either 1.5, 3, 5, 10, 15, 20, 30 or 45 min after the spray in each case. In group 1, the mean concentration of lidocaine reached the maximum of 1.05 micrograms.ml-1 at 5 min and decreased gradually after that with a small inter-individual variation. In group 2, after reaching the mean maximum concentration of 3.51 micrograms.ml-1 at 3 min, the serum level dropped quickly and then gradually decreased. There were a few cases where serum level was over 7 micrograms.ml-1. In group 2, after reaching the mean maximum concentration of 1.38 micrograms.ml-1 at 5 min, the serum level decreased more slowly, suggesting a slow absorption from the pharynx and/or the oral cavity. We conclude that the recommended dose of lidocaine for endotracheal administration is less than 2 mg.kg-1. 相似文献
77.
Y. Kubota R. Toda M. Kamada S. Nakamura T. Matsui Hiroshi Fukuyama 《Journal of Low Temperature Physics》2014,175(1-2):160-166
We describe some details of a new experimental setup for torsional oscillator (TO) measurement of $^4$ He monolayers adsorbed on a graphite surface. This setup is designed to seek for the possible supersolid phase, in which crystalline order coexists with superfluidity, in two dimensional (2D) solid $^4$ He below 300 mK. Among such 2D solids, the commensurate phase in the second layer on graphite is the most hopeful candidate for the novel supersolid phase since it is the lowest-density quantum solid ever found. An exfoliated graphite substrate we used is ZYX which has at least ten times longer surface coherence length compared to Grafoil, an exfoliated graphite most commonly used in previous experiments. The first version of TO we made has the resonant frequency of 786.8 Hz and the Q value of $1.1\times 10^5$ at $T \le 10$ mK. The resonant frequency of this particular TO without any He samples ( $f_{\mathrm {cell}}$ ) showed unexpectedly large temperature variation and non-reproducibility below 1 K as well as sudden jumps when mechanical shocks are applied to the experimental apparatus. We found the stability of $f_{\mathrm {cell}}$ is highly correlated with the temperature stability of 1 K pot in dilution refrigerator. 相似文献
78.
79.
In these years, a lot of environmental problems such as air pollution and exhaustion of fossil fuels have been discussed intensively. In our laboratory, a hydrogen-fueled propulsion system has been researched as an alternative to conventional systems. A hydrogen-fueled propulsion system is expected to have higher power, lighter weight and lower emissions. However, for the practical use, there exist many problems that must be overcome. Considering these backgrounds, jet engines with hydrogen-fueled combustion within a turbine blade passage have been studied. Although some studies have been made on injecting and burning hydrogen fuel from a stator surface, little is known about the interaction between a tip leakage vortex near the suction side of a rotor tip and hydrogen-fueled combustion. The purpose of this study is to clarify the influence of the tip leakage vortex on the characteristics of the 3-dimensional flow field with hydrogen-fueled combustion within a turbine blade passage. Reynolds-averaged compressible Navier-Stokes equations are solved with incorporating a k-ε turbulence and a reduced chemical mechanism models. Using the computational results, the 3-dimensional turbulent flow field with chemical reactions is numerically visualized, and the three-dimensional turbulent flow fields with hydrogen combustion and the structure of the tip leakage vortex are investigated. 相似文献
80.
Tomohiro Fujii Jun Nishikawa Soichiro Fukuda Naoto Kubota Junzo Nojima Koichi Fujisawa Ryo Ogawa Atsushi Goto Koichi Hamabe Shinichi Hashimoto Aung Phyo Wai Hisashi Iizasa Hironori Yoshiyama Kohei Sakai Yutaka Suehiro Takahiro Yamasaki Taro Takami 《International journal of molecular sciences》2022,23(18)
DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of , which was discovered by screening for demethylating agents. MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with MC180295. MKN28 cells infected with EBV were sensitive to MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and MC180295 could up-regulate their expression. In conclusion, MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle. MC180295相似文献