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排序方式: 共有623条查询结果,搜索用时 15 毫秒
101.
Kondo A Noguchi H Ohnishi S Kajiro H Tohdoh A Hattori Y Xu WC Tanaka H Kanoh H Kaneko K 《Nano letters》2006,6(11):2581-2584
Crystal-to-crystal transformation from a 3D interpenetrated-type MOF {[Cu(BF(4))(2)(bpy)(H(2)O)(2)] (bpy)} (1) to a 2D square-grid-type [Cu(BF(4))(2)(bpy)(2)] (2) (bpy = 4,4'-bipyridine) was observed. It was derived from dehydration and confirmed by in situ FT-IR, TG, and elemental analysis. Moreover, we elucidate the novel expansion/shrinkage dynamic modulation of 2 triggered by clathrate formation with gas molecules. 相似文献
102.
103.
Yokoyama Y Kawashima H Kanie H 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(9):1551-1553
The electrical properties of an X-cut, length-extensional mode quartz crystal resonator of a cut angle theta around the X-axis were calculated by a variational method using stresses as trial functions. Analytical expressions of stresses were estimated by a linear regression on a cut angle best-fit to the results of finite-element method. The calculated dependence of the capacitance ratio on the cut angle was consistent with the measured results. 相似文献
104.
The atomic-bridging type negative oxide charge in SiO2 is investigated using the Fe-contaminated (001) surface of n-type Si wafers. The investigation is done on the basis of a chemical analysis and a method in which the frequency-dependent alternating current (AC) surface photovoltage (SPV) is measured. At room temperature, an AC SPV appears and gradually increases, saturating after approximately one day (with an Fe concentration on the Si surface of 4.0 × 1013 atoms/cm2). The AC SPV eventually becomes inversely proportional to frequency except at very low frequencies (< 10 Hz) corresponding to weak or strong inversion, indicating that the negative Fe induced oxide charge appears in the form of a (FeOSi)− network. Also, in Fe-contaminated n-type Si(001) surfaces thermally oxidized at between 550 and 650 °C for 60 min, strong inversion is unquestionably observed, proving that the (FeOSi)− network survives and that most of the added Fe has segregated into the region closest to the surface of the thin SiO2 film. At 850 °C and/or for long oxidation times, the AC SPV decreases and ultimately disappears, implying that the (FeOSi)− network has collapsed and may have changed into Fe2O3. A model for the metal-induced negative oxide charge in the conventional oxide charge diagram is proposed. 相似文献
105.
Tanaka H Hong L Fukumori M Negishi R Kobayashi Y Tanaka D Ogawa T 《Nanotechnology》2012,23(21):215701
Nanoparticles of N,N'-bis(n-alkyl)tetracarbonatenaphthalenediimide (NDI) were adsorbed on single-walled carbon nanotube (SWNT) wires dispersed on a SiO(2) substrate. The electrical properties were measured along the long axis of the SWNTs, and in all cases through the nanoparticles showed rectification in semiconducting I-V curve. The plateau width of the I-V curve through the NDI nanoparticles on metallic SWNTs decreased as the particle size increased, while the rectification ratio increased. The conduction mechanism was changed from tunneling conduction to Schottky-like conduction and their boundary is at about 3 nm diameter. 相似文献
106.
T. Mizokawa T. Sudayama Y. Wakisaka D. Ootsuki M. Imaizumi T. Noji Y. Koike S. Pyon K. Kudo M. Nohara H. Anzai M. Arita H. Namatame M. Taniguchi N. L. Saini 《Journal of Superconductivity and Novel Magnetism》2012,25(5):1343-1346
We have studied the electronic structure of FeSe1?x Te x and Ir1?x Pt x Te2 using photoemission spectroscopy. For FeSe1?x Te x , angle-resolved photoemission results indicate that the Fe 3d yz/zx orbital degeneracy at ?? point and orbitally induced Peierls effect in the tetragonal lattice play important roles for the superconductivity. It is suggested that the Jahn-Teller instability of the yz/zx states couples with local lattice distortion derived from the Te substitution for Se and provides an inhomogeneous electronic state. Photoemission results of IrTe2 with triangular lattice are also consistent with the orbitally induced Peierls scenario. The Pt substitution for Ir suppresses the static band Jahn?CTeller effect and induces an inhomogeneous electronic state in which orbital (or bond or nematic) fluctuations may help superconductivity through the Peierls effect. 相似文献
107.
Yong-Jun LiuYan Cheng Tomonori OhbaKatsumi Kaneko Hirofumi Kanoh 《International Journal of Hydrogen Energy》2011,36(20):12902-12908
A nanocrystalline composite of lithium nitride and lithium carbide was synthesized through melt infiltration of lithium metal into the mesopores of carbon aerogels followed by nitrogenation with nitrogen gas. The structure, surface properties, and morphology of the prepared samples were examined by XRD, N2 adsorption at 77 K, FE-SEM, FE-TEM, and TPD/MS. It was found that some of the lithium metal reacted with the carbon to form lithium carbide, and some of the lithium metal was transformed into lithium nitride by nitrogenation, yielding a composite of lithium nitride and lithium carbide. Relative to the bulk lithium nitride, the lithium nitride in the composite showed a significantly enhanced sequential hydrogen absorption capacity and a lowered temperature of hydrogenation/dehydrogenation. 相似文献
108.
Hirofumi SumiPramote Puengjinda Hiroki MuroyamaToshiaki Matsui Koichi Eguchi 《Journal of power sources》2011,196(15):6048-6054
The effect of crystal structure of yttria- (YSZ) and scandia-stabilized zirconia (ScSZ) in nickel-based SOFC anodes was investigated in relation with carbon deposition and oxidation behavior in methane fuel. The lattice parameter of the zirconia decreased by the dissolution of 1-2 mol%Ni to YSZ and ScSZ. For Ni-doped ScSZ, the lattice parameter of the zirconia increased by the Ni dissolution, and the crystal structure of the zirconia was modified after reduction treatment. New finer Ni particles were formed around original Ni grains accompanied by the decrease in Ni solubility to ScSZ after reduction treatment. Carbon deposition was initiated near the boundary between Ni particles and YSZ (or ScSZ) substrate in dry methane atmosphere. Furthermore, the rod-shaped carbon was observed to grow from the new finer Ni particles on the ScSZ substrate. On the other hand, a large amount of amorphous carbon was promoted to be deposited on Ni-YSZ cermet at a high temperature of 1273 K. The amorphous carbon, however, was oxidized at lower temperatures than graphite. The carbon deposition and oxidation behavior was strongly affected by the morphology and crystallinity of deposited carbon. 相似文献
109.
Masayasu Ito Shuzo Murakami Masaya Okumiya Shigeru Tokita Hideharu Niwa Yoshibumi Suigihara Hideki Tanaka Takeshi Watanabe Mika Yoshinaga Katsuhiro Miura Hideharu Komoda Yuji Miyajima Tetsuji Yasutomo Sanae Namatame Hiromasa Yamaguchi 《Building Simulation》2008,1(2):178-191
The importance of LCEM (life cycle energy management) has been recognized from the view of life cycle energy savings for sustainable
buildings. The purposes of this research are the proposal of an LCEM framework and development of prototype HVAC system simulation
tools for LCEM. In this paper, the necessity of energy simulation tools for LCEM is discussed, and the outline and solution
method of the simulation tool are shown. 相似文献
110.
Ryota Hosomi Kenji Fukunaga Midori Fukao Munehiro Yoshida Hirofumi Arai Seiji Kanda Toshimasa Nishiyama Teruyuki Kanada 《Food science and biotechnology》2012,21(5):1335-1342
This study evaluated phospholipids (PLs) containing n-3 polyunsaturated fatty acids (n-3 PUFAs) for their specific inherent effects and effects due to a combination of the presence of glycerophosphate structure and n-3 PUFAs on cholesterol metabolism in rats. Rats were fed a diet of AIN-93G containing soybean oil (SO, 7%), SO (5.8%)+fish oil (1.2%), SO (5.2%)+soybean PLs (1.8%), SO (5.2%)+PLs containing n-3 PUFAs (1.8%), and SO (4.0%)+fish oil (1.2%)+soybean PLs (1.8%). Diets with PLs containing n-3 PUFAs, and soybean PLs in combination with fish oil, resulted in decreased serum and liver cholesterol levels through enhancement of fecal cholesterol excretion and suppression of liver sterol regulatory element binding protein-2 mRNA expression compared with the diet containing soybean oil alone. This study shows that soybean PLs with added triacylglycerol that included n-3 PUFAs have the same effects on cholesterol metabolism as PLs containing n-3 PUFAs, and that these could be of benefit to people. 相似文献