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排序方式: 共有1759条查询结果,搜索用时 31 毫秒
91.
92.
Hideomi Koinuma Min-Sung Kim Toshiaki Asakawa Mamoru Yoshimoto 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(3):599-612
Abstract Several new processes have been developed for the preparation of fullerenes and thin films by using a pulsed excimer laser. The irradiation of a pulsed KrF excimer laser beam onto a C60 powder target produced single phase C60 thin films when the laser energy fluence was in the range between 40 and 50mJ/cm2. By atomic force microscopy, the laser-deposited C60 thin film was verified to have a surface far smoother that the surfaces of films produced by the conventional evaporation method. The stainless steel rods coated with this film exhibited an excellent tribological property. Cluster formation from SiC and other carbides MCn(M=Ti,W,B) was investigated by laser desorption time-of-flight mass spectrometry. No clear indication was observed for the production of such clusters as (SiC)60 and (MxC60-x) from the sintered targets directly as well as from the films laser deposited from the targets. However, C60 and C70 were found to exists in the laser-deposited films, indicating a new applicability of pulsed laser processing for segregative cluster synthesis from solid solution. Preliminiary results on thin film deposition via pulsed ablation of (Ba,Na)xSi46 clathrate were also presented. 相似文献
93.
Toru Obara Takeru Koga Terumitsu Miura Hiroshi Sekimoto 《Progress in Nuclear Energy》2008,50(2-6):556-559
Fundamental experiments were performed to determine the adhesion characteristics of polonium to different metals and to develop a filter for polonium evaporated from neutron-irradiated LBE. The results of the first experiments suggested that adhesion characteristics are almost the same for stainless steel and nickel metal. The results of the preliminary experiments for a polonium filter suggested that stainless steel mesh with thin wires could effectively collect polonium evaporated from neutron-irradiated LBE. In the experiments, stainless steel wire mesh was used, but from the results of adhesion experiment, it is expected that the same effect can be obtained with wire mesh made of other kinds of metal. 相似文献
94.
Saito M. Sugimori Y. Kohama Y. Yoshida Y. Miura N. Ishikuro H. Sakurai T. Kuroda T. 《Solid-State Circuits, IEEE Journal of》2010,45(1):134-141
An inductive-coupling programmable bus for NAND flash memory access in solid state drive (SSD) is presented. Compared to the conventional SSD, this wireless interface using relayed transmission reduces power consumption to 1/2, I/O circuit-layout area to 1/40, and achieves a data rate of 2 Gb/s in 0.18 ?m CMOS process. In addition, since this wireless interface enables one package to contain 64 chips, the number of packages is reduced to 1/8. 相似文献
95.
The effects of indium addition to CuAu on the alloy phase transformation behavior were investigated by hardness tests, electrical
resistivity measurements, X-ray diffraction and transmission electron microscopy. These established that indium additions
lower the critical temperature and stabilize the CuAu II phase at room temperature. Formation of the long period ordered phase
produces an age-hardening; although this age-hardening is retarded, the degree of hardening is comparable to that in CuAu.
It was noted that the axial ratio increases and the antiphase domain size decreases. 相似文献
96.
97.
Lead-bismuth eutectic (LBE) has good characteristics for the coolant and/or target of various nuclear systems, but it also has a problem of polonium contamination. In the study, baking experiment was performed to remove polonium contamination on type 316 stainless steel plate that was originated from neutron irradiated LBE. The contaminated type 316 stainless steel plate was baked in a vacuum condition at various temperatures from 200°C to 600°C. In the previous preliminary study, the effect of short time baking was investigated. In the study, the effect of long time baking was investigated. The detail of the experimental method was also described. The result of long time baking experiment showed that the baking method was effective for removal of polonium from stainless steel surface contaminated by neutron irradiated LBE, if the baking was performed at 500°C and higher in a vacuum condition. The obtained result was consistent to the previous preliminary study. 相似文献
98.
Rong-Jun Xie Naoto Hirosaki Mamoru Mitomo Takayuki Suehiro Xin Xu Hidehiko Tanaka 《Journal of the American Ceramic Society》2005,88(10):2883-2888
Rare-earth-doped Ca-α-SiAlON phosphors, with the compositions of (Ca1−3/2 x RE x ) m /2 Si12− m − n Al m+n O n N16− n (RE=Ce, Sm, and Dy, 0.5≤ m =2 n ≤3.0), were prepared by sintering at 1700°C for 2 h under 10 atm N2 . The concentration of rare earths varied from 3 to 30 at.% with respect to Ca. The photoluminescence (PL) properties were investigated as functions of the composition of the host matrix (i.e., m ) and the concentration of rare earths (i.e., x ). The results show that the emission properties can be optimized by tailoring m and x . The Ce3+ luminescence originating from the 4 f –5 d interconfigurational transitions is greatly affected by the environment surrounding the Ce3+ ions, which differs from the Sm3+ or Dy3+ luminescence arising from the 4 f –4 f intraconfigurational transitions. X-ray diffraction and scanning electron microscopy were used to explain the composition and concentration dependence of PL properties. 相似文献
99.
100.