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991.
Wickham SF Bath J Katsuda Y Endo M Hidaka K Sugiyama H Turberfield AJ 《Nature nanotechnology》2012,7(3):169-173
Synthetic molecular motors can be fuelled by the hydrolysis or hybridization of DNA. Such motors can move autonomously and programmably, and long-range transport has been observed on linear tracks. It has also been shown that DNA systems can compute. Here, we report a synthetic DNA-based system that integrates long-range transport and information processing. We show that the path of a motor through a network of tracks containing four possible routes can be programmed using instructions that are added externally or carried by the motor itself. When external control is used we find that 87% of the motors follow the correct path, and when internal control is used 71% of the motors follow the correct path. Programmable motion will allow the development of computing networks, molecular systems that can sort and process cargoes according to instructions that they carry, and assembly lines that can be reconfigured dynamically in response to changing demands. 相似文献
992.
A lithium-encapsulated fullerenol Li@C60(OH)18, as an example of a polar solvent-soluble endohedral fullerene derivative, has been synthesized and fully characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, UV spectroscopy, electron spin resonance (ESR) spectroscopy, matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), elemental analysis, thermogravimetric analysis, and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and the particle size was determined using the induced grating (IG) method, and scanning probe microscopy. The encapsulated Li+ was clearly detected by 7Li NMR at very high field in the range −15 to −19 ppm, an intermediate lithium-encapsulated fullerenol was detected by MALDI-TOF-MS, and the molar ratio of lithium-encapsulated fullerenol to empty fullerenol was quantitatively determined to be 12:88 by ICP-AES. The solid-state ESR and particle size measurements using the IG method showed the characteristic anionic behavior with no external counter cations, in what can be called a “cation-encapsulated anion nanoparticle”, revealing the drastic differences between its properties and those of empty C60(OH)16. 相似文献
993.
Tetsuhiko Maeda Keiichi NishidaManabu Tange Toru TakahashiAkihiro Nakano Hiroshi ItoYasuo Hasegawa Masao MasudaYoshiaki Kawakami 《International Journal of Hydrogen Energy》2011,36(17):10845-10854
Numerical simulation of a hydrogen storage tank of a Totalized Hydrogen Energy Utilization System (THEUS) for application to commercial buildings was done to verify the practicality of THEUS. THEUS consists of a fuel cell, water electrolyzer, hydrogen storage tank and their auxiliary machinery. The hydrogen storage tanks with metal hydrides for load leveling have been previously experimentally investigated as an important element of THEUS. A hydrogen storage tank with 50 kg AB5 type metal hydride was assembled to investigate the hydrogen-absorbing/desorbing process, which is exothermic/endothermic process. The goal of this tank is to recover the cold heat of the endothermic process for air conditioning, and thus improve the efficiency of THEUS. To verify the practical effectiveness of this improved system, we developed a numerical simulation code of hydrogen storage tank with metal hydride. The code was validated by comparing its results with experimental results. In this code the specific heat value of the upper and lower flanges of the hydrogen storage tank was adjusted to be equal to the thermal capacity of the entire tank. The simulation results reproduce well the experimental results. 相似文献
994.
Ethanol oxidation reaction activity of highly dispersed Pt/SnO2 double nanoparticles on carbon black
Eiji Higuchi Kazumasa MiyataTomonori Takase Hiroshi Inoue 《Journal of power sources》2011,196(4):1730-1737
Highly dispersed Pt and SnO2 double nanoparticles containing different Pt/Sn ratios (denoted as Pt/SnO2/CB) were prepared on carbon black (CB) by the modified Bönnemann method. The average size of Pt and SnO2 nanoparticles was 3.1 ± 0.5 nm and 2.5 ± 0.3 nm, respectively, in Pt/SnO2(3:1)/CB, 3.0 ± 0.5 nm and 2.6 ± 0.3 nm, respectively, in Pt/SnO2(1:1)/CB, and 2.8 ± 0.5 nm and 2.5 ± 0.3 nm, respectively, in Pt/SnO2(1:3)/CB. The Pt/SnO2(3:1)/CB electrode showed the highest specific activity and lowest overpotential for ethanol oxidation reaction (EOR), and was superior to a Pt/CB electrode. Current density for EOR at 0.40 and 0.60 V vs. reversible hydrogen electrode for the Pt/SnO2(3:1)/CB electrode decayed more slowly than that for the Pt/CB electrode because of a synergistic effect between Pt and SnO2 nanoparticles. The predominant reaction product was acetic acid, and its current efficiency was about 70%, while that for CO2 production was about 30%. 相似文献
995.
Bismuth–tin binary alloys containing high bismuth concentrations of 40 to 77% were continuously cast into wires of approximately 2 mm in diameter with casting speeds between 15 and 150 mm min?1 using the Ohno Continuous Casting (OCC) process. The microstructure was examined and tensile tests were performed for wires cast at various speeds. It was found that for slowly cast wires containing large primary bismuth dendrites, bismuth fracture occurring along the (111) plane exerted a key role in wire fracture, while microstructures with refined bismuth dendrites exhibited a mixture of bismuth cracks and inter-phase decohesion, allowing the accommodation of larger strain before wire fracture. For wires with microstructures containing primary tin dendrites, inter-phase decohesion played a key role in wire fracture. 相似文献
996.
Hiroshi Yoshihara 《Engineering Fracture Mechanics》2010,77(13):2537-745
Using specimens of medium density fiberboard, double cantilever beam and three-point bend end-notched flexure tests were conducted to obtain the mode I and mode II initiation fracture toughness and resistance curve for in-plane and through-the-thickness systems. The mode I initiation fracture toughness was smaller than that of mode II for the in-plane crack systems, but this tendency was inverse for the through-the-thickness systems. The fracture toughness increased during the crack propagation because of the significant fiber bridgings induced between the crack surfaces, but the increase of the mode I propagation fracture toughness was moderated after the crack reached a certain length. In contrast, the mode II propagation fracture toughness continuously increased during the crack propagation. 相似文献
997.
Y. H. Matsuda J. L. Her T. Inami K. Ohwada Z. W. Ouyang K. Okada H. Nojiri A. Mitsuda H. Wada N. Kawamura M. Suzuki 《Journal of Low Temperature Physics》2010,159(1-2):292-296
X-ray magnetic circular dichroism (XMCD) in Eu-based valence fluctuating compounds, EuNi2(Si1?x Ge x )2 (x=0.82, 0.85) and EuNi2P2 are investigated at high magnetic fields up to 40 T. Distinct two XMCD peaks corresponding to different valence states, i.e., Eu2+ and Eu3+ states are observed in EuNi2(Si1?x Ge x )2 (x=0.82) and EuNi2P2 at the L absorption edges (2p→5d). This suggests that the Eu 5d electrons are magnetically polarized in the both valence states. Since Eu3+ state has nonmagnetic ground state J=0, where J is total angular momentum, finite XMCD of Eu3+ state can be closely related to the magnetic polarization of the conduction electrons that is induced by the local magnetic moments of Eu2+ (J=7/2) state through the strong hybridization. 相似文献
998.
Shunsuke Mochizuki Akira Teramoto Fuyuko Yamashita Yasuhiko Kasama Yoshiyuki Sato Hiroshi Inomata 《Journal of Materials Science》2010,45(6):1588-1594
Gas–antisolvent (GAS) process using CO2 successfully prepared crystals of fullerene (C60) from a toluene solution through a precipitation. Particle sizes of precipitated C60 could be easily controlled by changing the initial pressurization rate of CO2, the temperature at the initial pressurization, and the quantity of C60. Fullerene particles obtained by GAS method had regular octahedral shapes, whereas the particles obtained by adding liquid
ethanol as an antisolvent to C60 solution did not have such shape. Particle sizes could be changed in a range of 1.0–8.5 μm by GAS method; they were wider
than the range of particles obtained by ethanol addition (0.7–1.8 μm). 相似文献
999.
Hiroshi Abe Yusuke Imai Takefumi Goto Yukihiro Yoshimura Masami Aono Takahiro Takekiyo Hitoshi Matsumoto Takashi Arai 《Metallurgical and Materials Transactions A》2010,41(5):1137-1143
Crystal structures of room-temperature ionic liquid (RTIL)-H2O mixtures are determined by the X-ray diffraction method. The RTIL is N,N-diethyl-N-methyl-N-2-methoxyethyl ammonium tetrafluoroborate, [DEME][BF4]. At 0.9 mol pct H2O, two kinds of superstructures occur simultaneously without a strain. Also, the volume of the unit cell is very small only
at 0.9 mol pct additives. This relates to the composite domain structure, including a twin-related one, as an elastic anomaly.
At other water concentrations, such an extraordinary behavior is not observable. By assuming a sublattice having an equivalent
lattice constant, a water network at 1 mol pct H2O is simulated using a Monte Carlo (MC) method. The network develops over the medium range in the simulation box. 相似文献
1000.
Kimikazu Sasa Tsutomu Takahashi Yuki Tosaki Yuki Matsushi Keisuke Sueki Michiko Tamari Takahiro Amano Toshiyuki Oki Shozo Mihara Yoshihiro Yamato Yasuo Nagashima Kotaro Bessho Norikazu Kinoshita Hiroshi Matsumura 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(7-8):871-875
We present the current status and research programs of a multinuclide accelerator mass spectrometry (AMS) system on the 12UD Pelletron tandem accelerator at the University of Tsukuba (Tsukuba AMS system), Japan. A maximum terminal voltage of 12 MV is available for the AMS system. The Tsukuba AMS system can measure environmental levels of long-lived radioisotopes of 14C, 26Al, 36Cl and 129I by employing a molecular pilot beam. Recently, enhancements in AMS techniques and equipment, including sample preparation, the ion source and the data acquisition system, have improved the performance of 36Cl-AMS. The standard deviation of fluctuations is typically ±2%, and the machine background level for the 36Cl/Cl ratio is lower than 1 × 10?15 with a halite sample. We have measured over 500 samples in 1 year, including samples for earth and environmental sciences and nuclear safety research. 相似文献