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991.
M. Shibata T. Arai A. Fukuda H. Funahashi T. Haseyama S. Ikeda K. Imai Y. Isozumi T. Kato Y. Kido A. Matsubara S. Matsuki T. Mizusaki R. Nakanishi T. Nishimura D. Ohsawa A. Sawada Y. Takahashi M. Tosaki S. Yamada K. Yamamoto 《Journal of Low Temperature Physics》2008,151(3-4):1043-1048
A microwave single-photon detector was developed with highly-excited alkaline Rydberg-atoms in a cooled resonant cavity to
search for dark matter axions. This detector belongs to a microwave single-photon counter, thus being free from the standard
quantum limit (SQL). High sensitivity of the present detector system was demonstrated by measuring the thermal blackbody radiations
in the cavity at temperatures as low as 70 mK where the sensitivity is below the SQL.
The detection sensitivity of the present system is mainly limited by stray electric fields present in the detection region.
Practical design of a new experimental scheme with a guiding electric field through the atomic-beam trajectory is here presented
and discussed to avoid the effect of stray electric field and thus to improve the detection sensitivity.
相似文献
992.
D. Fukuda G. Fujii A. Yoshizawa H. Tsuchida R. M. T. Damayanthi H. Takahashi S. Inoue M. Ohkubo 《Journal of Low Temperature Physics》2008,151(1-2):100-105
We have developed new photon number resolving detectors with titanium transition edge sensors (Ti-TESs) for a high counting
rate operation in quantum information. The titanium superconducting films were fabricated by ultra-high vacuum electron beam
evaporation, and showed a sharp superconducting transition at 359 mK. The device was coupled to a single mode optical fiber,
and cooled down to 100 mK. Some of optical responses of the devices were measured by illuminating heavily attenuated laser
pulses at wavelengths of 405 and 1550 nm. As a result, the device showed a fast decay time constant of 300 ns, which enables
the operation at the counting rate of 400 kcps. The energy resolution was 0.76 eV at 405 nm and 0.68 eV at 1.5 μm, that make it possible to clearly resolve the number of photons of incident laser pulses. These features of the high counting
rate operation and the reasonable energy resolution are very promising for quantum information field.
相似文献
993.
Hongfei Lin Takashi Fujii Reisuke Takisawa Toru Takahashi Toshiyuki Hashida 《Journal of Materials Science》2008,43(7):2307-2315
The hydrothermal autoclave experiments were conducted to simulate the interactions in the scCO2/water/rock minerals (quartz, biotite and granite) reaction systems using a Hastelloy C reaction cell at 100 °C. The dissolution
characteristics of rock minerals and their surface texture alternation after hydrothermal treatment were examined by ICP-AES
and SEM/EDX investigation, respectively. The results suggested that the hydrolysis of plagioclase phase should be mainly responsible
for the elements dissolved from the Iidate granite samples. The dissolution was encouraged by the introduction of CO2 in the water/granite system, and generated an unknown aluminosilicate. No distinct chemical alternations occurred in the
water-free scCO2/granite system, which indicated that rock minerals should be chemically stable in the water-free scCO2 fluids under the current mild experimental conditions. Both the highest concentration of Ca existing in the scCO2/vapor/granite system and the SEM observation results of calcite deposit, suggested that a meaningful CO2 minerals trapping process should be potential in the CO2-rich field during a short physicochemical interaction period. 相似文献
994.
Although conventional model reference adaptive control (MRAC) achieves good tracking performance for cylinder control, the controller structure is much more complicated and has less robustness to disturbance in real applications. This paper discusses the use of simple adaptive control (SAC) for positioning a water hydraulic servo cylinder system. Compared with MRAC, SAC has a simpler and lower order structure, i.e., higher feasibility. The control performance of SAC is examined and evaluated on a water hydraulic servo cylinder system. With the recent increased concerns over global environmental problems, the water hydraulic technique using pure tap water as a pressure medium has become a new drive source comparable to electric, oil hydraulic, and pneumatic drive systems. This technique is also preferred because of its high power density, high safety against fire hazards in production plants, and easy availability. However, the main problems for precise control in a water hydraulic system are steady state errors and overshoot due to its large friction torque and considerable leakage flow. MRAC has been already applied to compensate for these effects, and better control performances have been obtained. However, there have been no reports on the application of SAC for water hydraulics. To make clear the merits of SAC, the tracking control performance and robustness are discussed based on experimental results. SAC is confirmed to give better tracking performance compared with PI control, and a control precision comparable to MRAC (within 10 μm of the reference position) and higher robustness to parameter change, despite the simple controller. The research results ensure a wider application of simple adaptive control in real mechanical systems. 相似文献
995.
T Takahashi H Suzuki T Inuzuka H Shibata M Maki 《International journal of molecular sciences》2012,13(6):7532-7549
ALG-2 is a penta-EF-hand Ca(2+)-binding protein and interacts with a variety of intracellular proteins. Two types of ALG-2-binding motifs have been determined: type 1, PXYPXnYP (X, variable; n = 4), in ALIX and PLSCR3; type 2, PXPGF, in Sec31A and PLSCR3. The previously solved X-ray crystal structure of the complex between ALG-2 and an ALIX peptide containing type 1 motif showed that the peptide binds to Pocket 1 and Pocket 2. Co-crystallization of ALG-2 and type 2 motif-containing peptides has not been successful. To gain insights into the molecular basis of type 2 motif recognition, we searched for a new hydrophobic cavity by computational algorithms using MetaPocket 2.0 based on 3D structures of ALG-2. The predicted hydrophobic pocket designated Pocket 3 fits with N-acetyl-ProAlaProGlyPhe-amide, a virtual penta-peptide derived from one of the two types of ALG-2-binding sites in PLSCR3 (type 2 motif), using the molecular docking software AutoDock Vina. We investigated effects of amino acid substitutions of the predicted binding sites on binding abilities by pulldown assays using glutathione-S-transferase -fused ALG-2 of wild-type and mutant proteins and lysates of cells expressing green fluorescent protein -fused PLSCR3 of wild-type and mutants. Substitution of either L52 with Ala or F148 with Ser of ALG-2 caused loss of binding abilities to PLSCR3 lacking type 1 motif but retained those to PLSCR3 lacking type 2 motif, strongly supporting the hypothesis that Pocket 3 is the binding site for type 2 motif. 相似文献
996.
Sarker PK Takahashi J Kawamoto Y Obayashi Y Kaneko T Kobayashi K 《International journal of molecular sciences》2012,13(1):1006-1017
Aqueous solutions of isovaline and its precursor molecule, 5-ethyl-5-methylhydantoin, were irradiated with ultraviolet and γ-ray photons, to evaluate their structural stability against space radiation. The degree of photolysis was measured and irradiation products were identified using chiral, reversed-phase and ion-exchange high-performance liquid chromatography. The experimental results show that the degree of photolysis of 5-ethyl-5-methylhydantoin is more significant than that of isovaline under ultraviolet light irradiation, while the results under γ-ray irradiation are the opposite. As the products of isovaline photolysis, aspartic acid, serine, glutamic acid and alanine were dominantly detected. 相似文献
997.
Goto K Waki M Takahashi T Kadowaki M Setou M 《Chembiochem : a European journal of chemical biology》2012,13(8):1103-1106
MIMS visualises metabolism: A recent publication by Steinhauser and co-workers presents a novel application of multi-isotope mass spectrometry (MIMS) to visualise physiological metabolism in live mammalian organisms, and validate the "immortal strand hypothesis" of asymmetric chromosomal division of stem cells in the small intestine. 相似文献
998.
Yoshiyuki Mizushina Yoshihiro Takahashi Yoshihiro Sato Yasuhiro Yamaguchi Toshifumi Takeuchi Isoko Kuriyama Fumio Sugawara Hiromi Yoshida 《Food chemistry》2012
During the screening of selective DNA polymerase (pol) inhibitors, we isolated two glucosyl compounds, a cerebroside (glucosyl ceramide, AS-1-4, compound 1) and a steroidal glycoside (eleutheroside A, compound 2) from soybean (Glycine max L.). Compounds 1 and 2 selectively inhibited the activity of eukaryotic pol λ in vitro, with IC50 values of 12.2 and 9.1 μM, respectively. These compounds did not influence the activities of other eukaryotic pols including those from the A-family (pol γ), B-family (pols α, δ and ε), and Y-family (pols η, ι and κ), and also showed no effect on the activity of pol β which is of the same family (X) as pol λ. The tendency for in vitro pol λ inhibition by these compounds showed a positive correlation with the in vivo suppression of TPA (12-O-tetradecanoylphorbol-13-acetate)-induced inflammation in mouse ear. These results suggest that these glucosyl compounds from soybean may be useful for their anti-inflammatory properties. 相似文献
999.
Takatoshi Shindo Tsuguhiro Takahashi Tatsuki Okamoto Takashi Kuraishi 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(5):450-453
Application of Bayes' theorem for the evaluation of diagnostic results of electric facilities is described. A concept of risk assessment method based on the diagnosis results is proposed and the effects of various parameters on the risk are clarified. Based on these results, a rational renewal scheme using diagnostic results is proposed. In addition, the prior probability based on the data of actual facilities is investigated and it is found that the data available so far is insufficient and more data are required for the detailed analysis. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
1000.
As the density and operating speed of complementary metal oxide semiconductor (CMOS) circuits increases, dynamic power dissipation has become a critical concern in the design and development—of personal information systems and large computers. The reduction of supply voltage, node capacitance, and switching activity are common approaches used in conventional CMOS. In adiabatic switching circuits, the current flow through transistors can be significantly reduced by ensuring uniform charge transfer over the entire available time. This paper presents the simulation of this current in two-phase clocked adiabatic static CMOS logic (2PASCL) and conventional CMOS. From the SPICE simulations, at transition frequencies from 1 to 12 MHz, a 4×4-bit array 2PASCL multiplier shows a maximum reduction in power dissipation of 77% relative to that of a static CMOS. The measurement results of a 4×4-bit array 2PASCL multiplier demonstrate a 57% reduction compared to a 4×4-bit array two-phase clocked adiabatic dynamic CMOS logic (2PADCL). These results indicate that 2PASCL technology can be advantageous when applied to low-power digital devices operated at low frequencies, such as radio-frequency identification (RFID) tags, smart cards, and sensors. 相似文献