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991.
992.
Fumiaki Mitsugi Yoshihiro Umeda Norihiro Sakai Tomoaki Ikegami 《Thin solid films》2010,518(22):6334-1307
Recently, transparent conducting oxide thin films have attracted attention for the application to transparent conducting electrodes. In this work, we evaluated the uniformity of electrical, optical and structural properties for gallium doped zinc oxide thin films prepared on the 10 × 10 cm2 silica glass substrate by pulsed laser deposition. The resistivity, carrier concentration, mobility, bonding state and atomic composition of the film were uniform along in-plane and depth direction over the 10 × 10 cm2 area of the substrate. The film showed the average transmittance of 81-87%, resistivity of 1.4 × 10− 3 Ω cm, carrier concentration of 9.7 × 1020/cm3 and mobility of 5 cm2/Vs in spite of the amorphous X-ray diffraction pattern. The gradual thickness distribution was found, however, the potential for large-area and low temperature deposition of transparent conducting oxide thin film using pulsed laser deposition method was confirmed. 相似文献
993.
Aqueous chromatography utilizing pH-/temperature-responsive polymer stationary phases to separate ionic bioactive compounds 总被引:2,自引:0,他引:2
Cross-linked poly(N-isopropylacrylamide-co-acrylic acid) (poly(IPAAm-co-AAc))-grafted silica bead surfaces were prepared and applied as new column matrix materials that exploit temperature-responsive anionic chromatography to separate basic bioactive compounds, specifically catecholamine derivatives, in aqueous mobile phases. Since poly(IPAAm-co-AAc) has a well-known temperature-responsive phase transition and apparent pKa shift, polymer-grafted silica bead surfaces are expected to exhibit simultaneous hydrophilic/hydrophobic and charge density alterations under thermal stimuli. Elution behavior of catecholamine derivatives from a copolymer-modified bead packed column was monitored using aqueous mobile-phase HPLC under varying temperature and pH. Catecholamine derivatives had higher retention times on poly(IPAAm-co-AAc) columns at higher pH in comparison with those on noncharged PIPAAm reference columns, suggesting an electrostatic interaction as a separation mode. Temperature also affected the retention behavior of catecholamine derivatives. Optimal separation of four catecholamine derivatives was achieved at elevated temperature, 50 degrees C, and at pH 7.0. This is due to the increased hydrophobicity of the stationary phase as evidenced by the elution of a nonionic hydrophobic steroid. From these results, mutual influences of both electrostatic and hydrophobic interactions between basic catecholamine derivatives and pH-/temperature-responsive surfaces are noted. Consequently, elution of weakly charged bioactive compounds is readily regulated through the modulation of stationary-phase thermoresponsive hydrophilic/hydrophobic and charge density changes. 相似文献
994.
Observation of the intrinsic pinning of a magnetic domain wall in a ferromagnetic nanowire 总被引:1,自引:0,他引:1
Koyama T Chiba D Ueda K Kondou K Tanigawa H Fukami S Suzuki T Ohshima N Ishiwata N Nakatani Y Kobayashi K Ono T 《Nature materials》2011,10(3):194-197
The spin transfer torque is essential for electrical magnetization switching. When a magnetic domain wall is driven by an electric current through an adiabatic spin torque, the theory predicts a threshold current even for a perfect wire without any extrinsic pinning. The experimental confirmation of this 'intrinsic pinning', however, has long been missing. Here, we give evidence that this intrinsic pinning determines the threshold, and thus that the adiabatic spin torque dominates the domain wall motion in a perpendicularly magnetized Co/Ni nanowire. The intrinsic nature manifests itself both in the field-independent threshold current and in the presence of its minimum on tuning the wire width. The demonstrated domain wall motion purely due to the adiabatic spin torque will serve to achieve robust operation and low energy consumption in spintronic devices. 相似文献
995.
Carbon nanotubes (CNTs) were produced by laser ablation of a graphite composite target in argon and nitrogen ambient gas. To investigate the effect of nitrogen gas on CNTs formation, the plasma plume was examined using optical emission spectroscopy. The vibrational temperature of C2 molecules was estimated by fitting of a Swan band spectrum. The temperature in N2 ambient gas is lower than that in Ar ambient gas. In a nitrogen atmosphere, the spectrum intensity of C2 Swan band was enhanced and CN violet system was also observed. Soot collected in the reaction tube was observed using FE-SEM and TEM. The soot deposited in the nitrogen gas contained more bundled CNTs than those in Ar ambience. 相似文献
996.
Makoto Kobayashi Masashi Shimada Yuji Hatano Takuji Oda Brad Merrill Yasuhisa Oya Kenji Okuno 《Fusion Engineering and Design》2013,88(9-10):1749-1752
The deuterium trapping behaviors in tungsten damaged by light ions with lower energy (10 keV C+ and 3 keV He+) or a heavy ion with higher energy (2.8 MeV Fe2+) were compared by means of TDS to understand the effects of cascade collisions on deuterium retention in tungsten. By light ion irradiation, most of deuterium was trapped by vacancies, whose retention was almost saturated at the damage level of 0.2 dpa. For the heavy ion irradiation, the deuterium trapping by voids was found, indicating that cascade collisions by the heavy ion irradiation would create the voids in tungsten. Most of deuterium trapped by the voids was desorbed in higher temperature region compared to that trapped by vacancies. It was also found that deuterium could accumulate in the voids, resulting in the formation of blisters in tungsten. 相似文献
997.
Molecular pharmacology of voltage-dependent calcium channels 总被引:1,自引:0,他引:1
Y Mori G Mikala G Varadi T Kobayashi S Koch M Wakamori A Schwartz 《Canadian Metallurgical Quarterly》1996,72(2):83-109
Voltage-dependent Ca2+ channels serve as the only link to transduce membrane depolarization into cellular Ca(2+)-dependent reactions. A wide variety of chemical substances that have the ability to modulate Ca2+ channels have been demonstrated both for their clinic utility and for importance in elucidating the molecular basis of various biological responses. Recently, introduction of molecular biology to pharmacology has brought a great deal of information about the molecular basis of drug action in Ca2+ channels. In this review, we attempt to overview recent progress in understanding the interactions between Ca2+ channels and their blockers, namely Ca2+ antagonists, from a molecular and structural point of view. 相似文献
998.
Isamu Kobayashi 《Information Systems》1987,12(4):343-352
In classical database theory, relational calculus has long been used in expressing query formulae and integrity constraints. In fact, relational calculus formulae are much easier to deal with than first-order formulae when evaluating queries and validating database updates in the database environment. In deductive databases, however, first-order calculus is preferred because it is convenient when proof procedures are involved. Since both situations should coexist in advanced information systems, it is very desirable to devise a conversion procedure between relational calculus and first-order calculus. In this paper, interpretation of first-order formulae in the database environment is discussed first, then tuple calculus, an extension of relational calculus, is presented. This extension enables us to describe query formulae and general rules necessary in advanced information systems, in particular, dealing with complex objects. Finally, a conversion algorithm from first-order formulae into tuple calculus formulae is presented. Several application issues are also included. 相似文献
999.
The purpose of this paper is to show that a first-order adaptive regulator globally stabilizes a class of infinite-dimensional systems having no right half plane zeros. Knowledge of the spectrum of the model's high-frequency gain is not required. 相似文献
1000.
Underwater vehicle-manipulator systems (UVMS) are expected to play an important role in ocean exploration. It is considered
that UVMS will be operated by both automatic and manual control. We have proposed an automatic control method. In this article,
we propose a master-slave system for a UVMS. The effectiveness of the proposed master-slave control system is demonstrated
by using a floating underwater robot with a 2-link manipulator. 相似文献