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71.
1100 kV气体绝缘双断口断路器的开发与产品化 总被引:1,自引:0,他引:1
开发了一种用于气体绝缘组合电器(GIS)的1100kV50kASF6气体双断口断路器(GCB)。研究了这种断路器的各种特性,并成功完成了在绝缘、开断和机械性能等方面的型式试验。实现了GCB的小型化和轻量化。这种新开发的GCB已应用在中国特高压交流示范工程的GIS中,并已于2009年年初投入使用。 相似文献
72.
Kazuhiko Misawa Isao Matsuda Naoyuki T. Hashimoto Roy Lang 《Journal of Modern Optics》2013,60(16-18):2685-2692
Abstract A new optical telecommunication method combining time and frequency domain multiplexing is proposed using phase-controlled femtosecond pulses. Each pulse in a pulse train can be used as a data packet with data bits in the frequency domain. We call the new principle ‘wave packet engineering’, which adjusts the amplitude and phase of the wave function in device materials arbitrarily by controlling the spectral phase of femtosecond pulses. The optical phase-to-amplitude converter is demonstrated with organic dye molecules, in which the phase information in the phase-modulated pulses can be demodulated into the luminescence intensity. The luminescence intensity from cyanine dye molecules is observed to be chirp dependent, and is explained quantum mechanically in terms of coherent population transfer. The design principle of the device using semiconductor coupled quantum nanostructures is also discussed in terms of wave packet engineering. 相似文献
73.
A carbon film consisting nanocrystallites with mixed sp2 and sp3 bonds formed by using the electron cyclotron resonance (ECR) sputtering method was studied with respect to the changes in characteristics caused by electrochemical pretreatment (ECP). Unlike glassy carbon, our sputtered nanocrystalline carbon film deposited at an acceleration voltage of 75 V (ECR-75 nano-carbon film) largely retained its surface flatness after the ECP. This robust surface could be caused by an increase of 42% in the sp3 carbon realized by increasing the acceleration voltage during sputtering. The electrode activity of ECR-75 nano-carbon film was improved for surface sensitive species including Fe3+/2+ unlike the boron doped diamond (BDD) electrode. This is because a sufficient quantity of surface sp2 bonds remained and because the introduction of surface oxygen-containing groups is more efficient than with the BDD electrode. With pretreated ECR-75 nano-carbon film, the peak potential of glutathione was reduced solely due to the increase in the surface hydrophilicity with a sufficient quantity of surface sp2 bonds, thus achieving the lowest detection limit (0.4 μM) ever obtained with carbon electrodes. We also achieved the stable measurement of 30 μM of serotonin (20 times) without the electrode surface fouling found with other electrodes. 相似文献
74.
In a ball-on-disc wear test, an alumina ceramic body sliding against a silicon nitride ceramic body in water achieved an ultra-low friction coefficient (ULFC) of 0.004. The profilometer and EDX measurements indicated that the ULFC regime in this unmated Al2O3–Si3N4 pair was achieved because of the formation of a flat and smooth interface of nanometric roughness, which favored the hydrodynamic lubrication. The triboreactions formed silicon and aluminum hydroxides which contributed to decrease roughness and shear stress at the contact interface. This behavior enables the development of low energy loss water-based tribological systems using oxide ceramics. 相似文献
75.
Fumiya ShirakiTaeko Yoshikawa Akihiro Oshima Yuji OshimaYuya Takasawa Naoyuki FukutakeTomoko Gowa Oyama Tatsuya UrakawaHajime Fujita Tomohiro TakahashiToshitaka Oka Hisaaki KudoTakeshi Murakami Yoshimasa HamaMasakazu Washio 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(15):1777-1781
The graded energy deposition of heavy ion beam irradiation to polymeric materials was utilized to synthesize a novel proton exchange membrane (PEM) with the graded density of sulfonic acid groups toward the thickness direction. Stacked Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were irradiated by Xe54+ ion beam with the energy of 6 MeV/u under a vacuum condition. The induced trapped radicals by the irradiation were measured by electron spin resonance (ESR) spectroscopy. Irradiated films were grafted with styrene monomer and then sulfonated. X-ray photo-electron spectroscopy (XPS) spectra showed that the densities of sulfonic acid groups were controlled for injection “Surface” and transmit “Back” sides of the fabricated PEM. The membrane electrode assembly (MEA) fabricated by the function-graded PEM showed improved fuel cell performance in terms of voltage stability. It was expected that the function-graded PEM could control the graded concentration of sulfonic acid groups in PEM. 相似文献
76.
A series of ozone/UV treatment under injection of ozone with different ozone-gas bubble sizes was performed at pH 1.7 and 7.4. The increase in the bubble size and the decrease in pH enhanced the ozone utilization efficiency. The enhancement of ozone utilization efficiency was caused by the shift of the production pathway of hydroxyl radical (OH) from the OH production via O3 – to the UV photolysis of H2O2. The lower pH caused this shift through the chemical equilibrium of H2O2 and HO2 –, and the large bubbles caused this shift through the augmentation of H2O2 transport from the bubble surface to the bulk solution. 相似文献
77.
78.
Takayama H Takahashi S Moriya T Osada H Iwabuchi Y Kanoh N 《Chembiochem : a European journal of chemical biology》2011,12(18):2748-2752
Seeing below the surface: A small-molecule droplet array platform on an NADH-immobilized solid surface and a biotinylated acetophenone derivative were developed to identify the substrate candidates for soluble P450 enzymes of interest. This methodology is thought to be easily applicable to other class I P450 systems, including those that use NADPH as cofactor. 相似文献
79.
MAMMOS(Magnetic Amplifying Magneto- Optical System:磁畴扩大磁光系统 )是实现高密度磁光盘的有效方法。不仅能得到不依赖于磁畴长度的较大的读出信号振幅,而且还能实现超出光学系统衍射极限的分辨率。过去,为实现磁畴的复印与扩大,要对记录膜面施加垂直方向的外部磁场。而现在得知,同时施加垂直磁场和水平方向的磁场,可大幅度地提高微小磁畴的读出特性。确认采用施加水平磁场的方法,在λ =635 nm, NA=0.55的条件下, 0.15μ m的连续磁畴也能获得 BER=2× 10- 4的读出效果。 相似文献
80.
DCB test simulation of stitched CFRP laminates using interlaminar tension test results 总被引:1,自引:0,他引:1
A simulation model for the delamination extension of stitched CFRP laminates and 3-D orthogonal interlocked fabric composites (3-D OIFC) has been developed using a 2-D finite element method incorporating interlaminar tension test results to simulate the experimental results of their DCB tests. The mechanical properties of through-the-thickness fiber were determined from the results of interlaminar tension tests in which the specimen included only one through-the-thickness yarn. The fracture phenomena around the through-the-thickness thread, such as debonding from the in-plane layer, slack absorption, fiber bridging, and the pull-out of broken threads from the in-plane layers, are also introduced into the FEM model. The present FEM simulation results were compared to DCB test results for certain stitched laminates and a 3-D OIFC, and the simulation results showed good agreement with the experimental results of DCB tests, including the load–displacement curve and Mode I strain energy release rate (GI). While it was difficult to estimate GI accurately when the DCB test specimen included different types of z-fiber fracture modes, the present model of FEM analysis can simulate the experimental results of DCB tests of stitched laminates and 3-D OIFC. It is suggested that the GI of CFRP with arbitrary z-fiber densities can be predicted by using this FEM analysis model together with interlaminar tension test results. 相似文献