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排序方式: 共有647条查询结果,搜索用时 15 毫秒
101.
Kaoru Dokko Jun-ichi Sugaya Hirokazu Munakata Kiyoshi Kanamura 《Electrochimica acta》2005,51(5):966-971
Fabrications of micro-dot electrodes of LiCoO2 and Li4Ti5O12 on Au substrates were demonstrated using a sol-gel process combined with a micro-injection technology. A typical size of prepared dots was about 100 μm in diameter, and the dot population on the substrate was 2400 dots cm−2. The prepared LiCoO2 and Li4Ti5O12 micro-dot electrodes were characterized with scanning electron microscopy, X-ray diffraction, micro-Raman spectroscopy, and cyclic voltammetry. The prepared LiCoO2 and Li4Ti5O12 micro-dot electrodes were evaluated in an organic electrolyte as cathode and anode for lithium micro-battery, respectively. The LiCoO2 micro-dot electrode exhibited reversible electrochemical behavior in a potential range from 3.8 to 4.2 V versus Li/Li+, and the Li4Ti5O12 micro-dot electrode showed sharp redox peaks at 1.5 V. 相似文献
102.
103.
Suzuki M Maekita W Wada Y Nagai K Nakajima K Kimura K Fukuoka T Mori Y 《Nanotechnology》2008,19(26):265304
Using a dynamic oblique angle deposition technique, we demonstrate the direct formation of Ag nanorods with quasi-parallel major axes on a template layer of oxide having a strongly anisotropic surface morphology. The optical properties of the nanorods are tuned by varying the deposition conditions without any pre-?or post-treatment, and the resulting Ag nanorod arrays exhibit high surface-enhanced Raman scattering (SERS) activity. In addition to high macroscopic uniformity over a large area, our nanorod arrays contain a high density of isolated nanorods. Using the optimum Ag nanorod arrays, the SERS imaging of the microdroplets of a rhodamine 6G solution is successfully demonstrated. The space resolution of the imaging is of the order of at least a few μm. These features are suitable for the SERS imaging of biomaterials. 相似文献
104.
We performed Monte Carlo simulation of helium (He) ion induced secondary electron (SE) emission in order to compare the secondary electron image characteristics between He and gallium (Ga) scanning ion microscopes (SIM) and scanning electron microscope (SEM). For 10-50 keV He ion bombardment SE yield increases gradually with increasing the atomic number, Z2, of the target, as well as for the electron bombardment. However, for 30 keV Ga ion bombardment, SE yield shows an opposite Z2 dependence. The calculated SE yield is much larger than that for both electron and Ga ion bombardment. The incident angle dependence of the SE yield approximately obeys the inverse cosine law even at high angles of 85 degrees and more. On the other hand, for electron bombardment, the incident angle dependences are much weaker for low energy and high Z2. These indicate that the image contrast on He-SIM is clearer than those of SEM. Among the electron excitations by incident He ions, recoiled target atoms and excited electrons, the first one having narrow excitation volume dominates the SE yield, so that the spatial image resolution in SIM using zero-diameter He beams with the energies of 10-50 keV is prospected to be smaller or better (<0.1 nm) than for 30 keV Ga ion and 1 keV electron beams. 相似文献
105.
Oily Grime Formed on Hard Surfaces of Kitchen Appliances: Chemical Composition and Oxidation Mechanism 总被引:1,自引:1,他引:0
Takuya Tsutsui Masahiko Natsuhara Kaoru Yamada Yoshiaki Tanizawa 《Journal of surfactants and detergents》2007,10(1):53-59
The cooking of oil-containing food products at high temperatures results in an insoluble, unsightly, greasy layer of grime
on appliance surfaces in residential and commercial kitchens. Over time, adsorbed grime becomes difficult to remove using
normal dishwashing detergents. A number of studies have focused on the deterioration and oxidation of oils and the harmful
effects that volatile compounds associated with such processes have on human health. Little attention, however, has been paid
to kitchen grime. The present study examined grime obtained from the surfaces of appliances such as sirocco fans, filters,
and range hoods in residential kitchens in Tokyo. The grime was characterized by X-ray fluorescence spectroscopy (XRF), Fourier-transform
infrared spectroscopy (FT-IR), size exclusion chromatography (SEC), thermal hydrolysis methylation–gas chromatography–mass
spectroscopy (THM–GCMS), and nuclear magnetic resonance (NMR) techniques. The chemical composition and structure of the grime
differed from those of the edible oils. The grime consisted mainly of polymerized and oxidized triacylglycerols. Bridging
between unsaturated acyl groups of triglycerols occurred through thermal oxidation and aging in air, yielding their dimers,
trimers, and highly polymerized products while also transforming unsaturated acyl groups into saturated ones. Cross-linking
reactions involving dibasic acids also caused polymerization. Those polymerized products strongly adhered to the hard surfaces
of the appliances. Small amounts of cellulose fibers from air or towel may also play a role in mechanically stabilizing the
dirt structure.
相似文献
Yoshiaki TanizawaEmail: |
106.
107.
Software-Defined Networking (SDN) is a new network architecture with flexibility and scalability, researchers introduced the core idea of SDN into wireless
network, and a cooperative communication system based on network coding is proposed. In this paper, we carry on an investigation in differentiated service
strategy of network coding cooperative communication system. The meaning of differentiated services is for the different applications take different power
for data transmission and the transmission power is associated with their reliability needs. In other words, transmission power control is performed in the
presence of known reliability, we named the scheme Reliability-Bounded Transmission Power Control (RTPC) scheme. The RTPC scheme changes the way
in which all the applications in the past have been able to maintain the power to be transmitted, but the reliability requirements of different applications
will be transmitted with different transmission power. In addition, because of the nodes that far away from the sink node still exist a lot of energy when the
network died, so consider to improve the transmission power of non-hotpots nodes in order to increase the reliability of data transmission. The experimental
results show that the RTPC scheme can greatly improve the transmission reliability without affecting the network lifetime. 相似文献
108.
Micro total analysis systems. Latest advancements and trends 总被引:5,自引:0,他引:5
109.
Frame shuffling: a novel method for in vitro protein evolution 总被引:1,自引:0,他引:1
Kashiwagi K Isogai Y Nishiguchi K Shiba K 《Protein engineering, design & selection : PEDS》2006,19(3):135-140
We describe 'frame shuffling', a novel method for preparing artificial protein libraries. With this method, a Y-family DNA polymerase known to introduce frame shift mutations at high rates is utilized to scramble the reading frames of a parental gene. The resultant progeny produce mutant proteins having segmental sequence changes. Such frame-shuffled mutant proteins exhibit physicochemical properties that differ from those of proteins obtained using conventional mutagenesis. 相似文献
110.
Combustion characteristics of lean hydrogen/air mixture in a planar micro-channel with a bluff body were investigated experimentally and numerically. Effects of the inlet velocity and equivalence ratio on the blow-off limit, combustion efficiency and exhaust gas temperature were examined. The results show that the blow-off limit is greatly extended as compared with that of the micro-combustor without a bluff body. Moreover, the blow-off limit increases as the equivalence ratio is increased from 0.4 to 0.6. Furthermore, with the increase of inlet velocity, the flame front is prolonged and becomes narrower, and the high temperature segment of outer wall shifts downstream. In addition, the combustion efficiency and exhaust gas temperature increase first and then decrease with the increase of the inlet velocity. Finally, comparatively high combustion efficiency can be maintained over the whole combustible velocity range at a moderate equivalence ratio. 相似文献