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101.
Liquid Crystals: Liquid‐Crystalline Electrolytes for Lithium‐Ion Batteries: Ordered Assemblies of a Mesogen‐Containing Carbonate and a Lithium Salt (Adv. Funct. Mater. 8/2015)
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102.
This work reports the results of laboratory drilling tests conducted in order to measure improvements due to design and cutter modifications on PDC bits intended for use in geothermal well drilling. These tests, using 142.88 mm-dia. PDC full face bits, concentrated on improvements in bit life and cost performance. The tests were performed using granite drilling samples and a laboratory drilling machine at atmospheric conditions. The results from changes in bit and cutter shape are reported in the work. 相似文献
103.
Heat transfer during oscillatory flow in a circular straight tube with a solid‐core tube inserted in its center was numerically simulated. The purpose of the solid‐core tube is to enhance axial heat transfer by increasing the lateral heat transfer effect for high frequency of the oscillatory flow. Simulation results showed that (a) axial heat transfer increases with the increasing diameter of the solid‐core tube, (b) the material of the solid‐core tube does not significantly affect axial heat transfer, and (c) efficiency based on the ratio of heat transfer to the work done is higher than that in a bundle of circular capillary tubes. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(1): 61–74, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20094 相似文献
104.
Takuji YokoyamaRyo Ishii Tetsuji ItohKoichi Kitahata Shun-ichi MatsuuraTatsuo Tsunoda Satoshi HamakawaTaka-aki Hanaoka Hironobu NanbuFujio Mizukami 《Materials Letters》2011,65(1):67-69
We present a new enzymatic process for synthesis of l-theanine using glutaminase combined with immobilization technique on a mesoporous silica (MPS). The MPS was firstly attempted to modify with zirconia in order to enhance the durability against the reaction under high pH conditions. The glutaminase on the MPS successfully catalyzed the reaction for the synthesis of l-theanine. The glutaminase/MPS conjugate was subsequently recovered and employed for the reaction again. The conjugate showed the corresponding activity to the first synthesis. This indicates that the conjugate functions as a catalyst for synthesis of l-theanine, having the operational stability sufficient for reuse. 相似文献
105.
Goro Sato Taro Fukuyama Shin WatanabeHirokazu Ikeda Masayuki OhtaShin’nosuke Ishikawa Tadayuki Takahashi Hiroyuki ShirakiRyoichi Ohno 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):149-152
Schottky CdTe diode detectors suffer from a polarization phenomenon, which is characterized by degradation of the spectral properties over time following exposure to high bias voltage. This is considered attributable to charge accumulation at deep acceptor levels. A Schottky CdTe diode was illuminated with an infrared light for a certain period during a bias operation, and two opposite behaviors emerged. The detector showed a recovery when illuminated after the bias-induced polarization had completely progressed. Conversely, when the detector was illuminated before the emergence of bias-induced polarization, the degradation of the spectral properties was accelerated. Interpretation of these effects and discussion on the energy level of deep acceptors are presented. 相似文献
106.
Tomoya Ohno Kazunori Numakura Hidenobu Itoh Hisao Suzuki Takeshi Matsuda 《Advanced Powder Technology》2011,22(3):390-395
This paper describes control of the coating layer thickness and the crystallite size of the core–shell hybrid particles by controlling the process parameter. The core–shell hybrid particles were prepared using liquid phase deposition (LPD). We confirmed that the homogeneous coating was attained from the result of the zeta potential and the transmission electron microscope (TEM) observation. Furthermore, the coating layer microstructure was estimated using Brunauer–Emmett–Teller (BET) method. The obtained coating layer of titania was estimated using the band gap energy. Results indicate that the blue shift of the band gap energy signifies that the physical property of the hybrid particles was controlled by the coating layer thickness and the crystallite size, which are determined by the processing parameters. 相似文献
107.
Yi Ke Stephan Lany Joseph J. Berry John D. Perkins Philip A. Parilla Andriy Zakutayev Tim Ohno Ryan O'Hayre David S. Ginley 《Advanced functional materials》2014,24(19):2875-2882
The increase of the band gap in Zn1‐xMgxO alloys with added Mg facilitates tunable control of the conduction band alignment and the Fermi‐level position in oxide‐heterostructures. However, the maximal conductivity achievable by doping decreases considerably at higher Mg compositions, which limits practical application as a wide‐gap transparent conductive oxide. In this work, first‐principles calculations and material synthesis and characterization are combined to show that the leading cause of the conductivity decrease is the increased formation of acceptor‐like compensating intrinsic defects, such as zinc vacancies (VZn), which reduce the free electron concentration and decrease the mobility through ionized impurity scattering. Following the expectation that non‐equilibrium deposition techniques should create a more random distribution of oppositely charged dopants and defects compared to the thermodynamic limit, the paring between dopant GaZn and intrinsic defects VZn is studied as a means to reduce the ionized impurity scattering. Indeed, the post‐deposition annealing of Ga‐doped Zn0.7Mg0.3O films grown by pulsed laser deposition increases the mobility by 50% resulting in a conductivity as high as σ = 475 S cm‐1. 相似文献
108.
Reiichi Ohno 《Metallurgical and Materials Transactions B》1991,22(4):447-465
An investigation was made of the rates of removal of bismuth and lead from molten copper alloys stirred differently under
vacuum at 1403 K. The heating conditions, which corresponded to highest, intermediate, and lowest stirring, were referred
to as HC-A, HC-B, and HC-C, respectively. The rates of removal were described by a first-order rate equation involving the
final concentration of the impurity. The overall mass-transfer coefficient for bismuth or lead (i),K
i, was determined, and it was found that Ki(HC-A) > Ki(HC-B) but Ki(HC-B) < Ki(HC-C) in Cu-Bi, Cu-Pb, and Cu-Bi-Pb alloys. In general, it was found that Ki(Cu-Bi-Pb) > Ki(Cu-Bi) or Ki(Cu-Pb). Oxygen reducedK
i more than sulfur. The reducing effect of oxygen and sulfur was weakened when stirring rate increased. In vacuum melting of
Cu-Bi-Pb-O and Cu-Bi-Pb-S alloys under HC-C,K
i tended to decrease with increasing oxygen and sulfur concentrations. The loss of copper indicated that the rates were determined
by liquid-phase mass-transfer and evaporation. The liquid-phase mass-transfer coefficient,K
L, was calculated, and it was found thatK
L(UC- A) > KL(HC-B) but KL(HC-B) < KL(HC-C). The last relation was contrary to current theoretical prediction. A new model was assumed to account for this fact.
The observed relative volatility coefficients of bismuth and lead were much smaller than their respective theoretical coefficients.
Oxygen and sulfur adsorbed on the surface of the melt were considered to be close to equilibrium with their respective bulk
concentrations, and their effects on the evaporation mass-transfer coefficients for bismuth and lead were estimated to be
fairly small. This result means that the observed reduction ofK
i is due mostly to the decrease inK
L and made possible the calculation ofK
L. Oxygen decreasedK
L more than sulfur. In vacuum melting of Cu-Bi-Pb-O and Cu-Bi-Pb-S alloys under HC-C,K
L decreased linearly with increasing oxygen or sulfur concentration. The final concentrations of bismuth and lead in these
alloys under HC-C tended to increase with increasing oxygen and sulfur concentrations and tended to decrease with increasingK
i andK
L. 相似文献
109.
Okabe M. Okuno Y. Arakawa T. Tomioka I. Ohno T. Noda T. Hatanaka M. Kuramitsu Y. 《Solid-State Circuits, IEEE Journal of》1989,24(5):1280-1286
A 0.8- mu m CMOS sea-of-gates (SOG) array with first-level wiring channels perpendicular to transistor rows and 40 0K transistors is integrated on a 6*7-mm/sup 2/ chip. Implementation of a 64-bit multiplier shows 60-percent gate utilization and density of 1410 G/mm/sup 2/. The wiring length of the multiplier is 70 percent of that in a conventional SOG.<> 相似文献
110.