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91.
Yee-Chia Yeo Qiang Lu Ranade P. Takeuchi H. Yang K.J. Polishchuk I. Tsu-Jae King Chenming Hu Song S.C. Luan H.F. Dim-Lee Kwong 《Electron Device Letters, IEEE》2001,22(5):227-229
We report the first demonstration of a dual-metal gate complementary metal oxide semiconductor (CMOS) technology using titanium (Ti) and molybdenum (Mo) as the gate electrodes for the N-metal oxide semiconductor field effect transistors (N-MOSFETs) and P-metal oxide semiconductor field effect transistors (P-MOSFETs), respectively. The gate dielectric stack consists of a silicon oxy-nitride interfacial layer and a silicon nitride (Si3N4) dielectric layer formed by a rapid-thermal chemical vapor deposition (RTCVD) process. C-V characteristics show negligible gate depletion. Carrier mobilities comparable to that predicted by the universal mobility model for silicon dioxide (SiO2) are observed 相似文献
92.
Ralph Skomski Priyanka Manchanda Ichiro Takeuchi Jun Cui 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(7):1144-1150
The geometrical optimization of aligned hard-soft permanent-magnet nanocomposites is investigated by model calculations. Considered criteria are the shapes of the soft and c-axis-aligned hard phases, the packing fraction of the soft phase, and magnetostatic interactions. Taking into account that the energy product is enhanced via the volume fraction of the soft phase, subject to maintaining coercivity, we find that the best structures are soft-magnetic cubes as well as long rods with a square cross section. Comparing embedded soft cubes with embedded soft spheres of the same size, our nucleation-field analysis shows that the volume fraction of the soft phase is enhanced by 91%, with a coercivity reduction of only 25%. Magnetostatic interactions often but not always deteriorate the permanent-magnet performance, as exemplified by the example of MnBi:FeCo bilayers and multilayers. 相似文献
93.
Young Jin KimAmy C. Marschilok Kenneth J. TakeuchiEsther S. Takeuchi 《Journal of power sources》2011,196(16):6781-6787
Recently, we have shown silver vanadium phosphorous oxide (Ag2VO2PO4, SVPO) to be a promising cathode material for lithium based batteries. Whereas the first reported preparation of SVPO employed an elevated pressure, hydrothermal approach, we report herein a novel ambient pressure synthesis method to prepare SVPO, where our chimie douce preparation is readily scalable and provides material with a smaller, more consistent particle size and higher surface area relative to SVPO prepared via the hydrothermal method. Lithium electrochemical cells utilizing SVPO cathodes made by our new process show improved power capability under constant current and pulse conditions over cells containing cathode from SVPO prepared via the hydrothermal method. 相似文献
94.
A. Takeuchi N. Chen T. Wada Y. Yokoyama H. Kato A. Inoue J.W. Yeh 《Intermetallics》2011,19(10):1546-1554
A Pd20Pt20Cu20Ni20P20 bulk metallic glass (BMG) with a high-entropy (HE) alloy composition and a maximum diameter of 10 mm was fabricated by fluxed water quenching. The system and composition of the Pd20Pt20Cu20Ni20P20 alloy were determined from a prototype ternary Pd40Ni40P20 BMG in accordance with two strategic alloy designs of (1) HE alloy defined by an equi-atomic alloy with five or more elements and (2) exchangeability of the constituent elements with a similar chemical nature in the periodic table. Pd20Pt20Cu20Ni20P20 HE-BMG had a supercooled liquid range of 65 K and a reduced glass transition temperature of 0.71. Successful formation of Pd20Pt20Cu20Ni20P20 HE-BMG is significant to develop new alloys for HE alloys and BMGs. 相似文献
95.
Toshio Shimoo Hiroshi Takeuchi Kiyohito Okamura 《Journal of the American Ceramic Society》2001,84(3):566-570
Three types of polycarbosilane-derived SiC fibers—Nicalon, Hi-Nicalon, and Hi-Nicalon S—were exposed at temperatures of 1573–1773 K under a reduced pressure of 1.3 Pa. The thermal stability of the fibers was investigated through examinations of the gas evolution, grain growth, specific resistivity, fiber morphology, and tensile strength. The thermal decomposition of the silicon oxycarbide phase began at 1523 K; then, active oxidation of the β-SiC crystallites occurred at >1673 K. The active oxidation caused serious damage to the fiber structure, which resulted in significant degradation of the fiber strength. Hi-Nicalon had a tensile strength of ∼0.5 GPa after exposure at 1773 K, although Nicalon and Hi-Nicalon S fibers completely lost their strength, even after exposure at 1673 K. Hi-Nicalon fiber had relatively good thermal stability under reduced pressure. 相似文献
96.
Akihito Takeuchi Kazuhiro Hosono Gen Tatara 《Journal of Superconductivity and Novel Magnetism》2010,23(1):31-32
We show theoretically that charge and spin currents arise from spin dynamics in the presence of the spin–orbit interaction.
The dominant calculation is the inverse spin Hall effect, namely the spin current pumped from precession of local spins is
converted into the charge current by the spin–orbit interaction. The conversion mechanism is explained based on the conservation
laws of charge and spin. 相似文献
97.
A study was made to investigate an optimum condition for ruthenium tetraoxide staining of poly(butylene terephthalate) (PBT) with glass transition temperature as low as ca. 23 degrees C for TEM observation of melt-grown PBT crystals. The morphological study of ultrathin sections prepared based on optimum staining at 25 degrees C for 8 h revealed formation of fringed-micellar crystal nuclei in the early stage and folded-chain fringed-micellar crystals in the later stage of isothermal crystallization at 40 degrees C from melt. The fraction of chain-folded crystals increased with increasing crystallization temperature from the quantitative analysis of crystal thickness in comparison with the reported morphology using the replica method. 相似文献
98.
研究了不同谐振腔下不同透射率的Cr4 + ∶YAG调Q的激光输出特性。采用透射率为 82 %的Cr4 + ∶YAG ,在抽运功率 1 1W时 ,激光重复频率小于 3kHz,单脉冲能量达 2 0 μJ ,可以作为微脉冲激光雷达的发射光源。分析和比较了实验结果和理论计算 ,两者吻合较好 相似文献
99.
Molecular imprinting of biotin derivatives and its application to competitive binding assay using nonisotopic labeled ligands 总被引:2,自引:0,他引:2
Synthetic biotin-binding polymers were prepared by molecular imprinting. Methacrylic acid (MAA) was copolymerized with ethylene glycol dimethacrylate in the presence of biotin methyl ester (B-Me) in chloroform. Hydrogen-bonding-based complexation of B-Me with MAA generates the binding sites complementary to B-Me after extracting B-Me from the resulting copolymers. Data from NMR titration suggest a one-to-one prepolymerization complex formation of B-Me with MAA in chloroform. A possible complex structure was estimated by docking of the most stable conformers by intermolecular Monte Carlo conformational search under the assumption of a one-to-one association. The selectivity of the imprinted polymers was investigated and an imprinted polymer-based competitive binding assay for B-Me was demonstrated using biotin p-nitrophenyl ester as a nonisotopic-labeled ligand. 相似文献
100.
J. Mesot M. R. Norman H. Ding M. Randeria J. C. Campuzano A. Paramekanti H. M. Fretwell A. Kaminski T. Takeuchi T. Yokoya T. Sato T. Takahashi T. Mochiku K. Kadowaki 《Journal of Low Temperature Physics》1999,117(3-4):365-369
We use the gradient of the energy-integrated angle resolved photoemission (ARPES) intensity in order to define precisely the Fermi surface (FS) in BSCCO superconductors. We show that, independent of the photon energy, the FS is a hole barrel centered at (, ). Then, the superconducting gap along the FS is precisely determined from ARPES measurements on overdoped and underdoped samples of Bi2212. As the doping decreases, the maximum gap increases, but the slope of the gap near the nodes decreases. Though consistent with d-wave symmetry, the gap with underdoping cannot be fit by the simple cos(k
x) – cos(k
y) form. A comparison of our ARPES results with available penetration depth data indicates that the renormalization of the linear T suppression of the superfluid density at low temperatures due to quasiparticle excitations around the d-wave nodes is large and doping dependent. 相似文献