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排序方式: 共有103条查询结果,搜索用时 15 毫秒
31.
The bis(ethylenediamine) palladium (II) () complex can be an excellent precursor for rapid and highly-efficient intercalation into the layers of graphite oxide and thus for preparing carbon nanosheets (CNSs) and palladium nanoparticle (NP) composites. The composite materials obtained are of mesoporosity and have a great Pd content with Pd NPs uniformly distributed along the surface and the inside of CNS which contributes to a hydrogen uptake comparable with or higher than those on other reported Pd-supported nanostructured carbons. 相似文献
32.
Makoto Matsuura Masakazu Hatori Makinori Ikeda 《Nuclear Engineering and Design》2007,237(12-13):1419-1428
MONJU is a prototype fast breeder reactor (FBR) in Japan. The sodium–water reaction in the steam generator (SG) is one of the important safety assessment items for a sodium cooled reactor like MONJU. MONJU is equipped with hydrogen gas detectors for the small water leak detection, gas pressure gauges for the medium leak and sensors of rupture discs for the large leak. As a design basis accident, one tube failure then failure propagation of neighboring three tubes is assessed to verify the structural integrity of the secondary components. A latest evaluation method on the design margin against the overheating tube rupture showed that the present SG system had not an enough margin in the worst case. For improving the margin, it needs to shorten the time of the sodium–water reaction by earlier water leak detection in the SG and sooner water ejection from the SG tubes. Therefore, MONJU is now carrying out the following modification works: (1) addition of steam relief valves, (2) addition of a gas pressure gauge with changing the interlock logic and lowering the trigger level, (3) reducing the opening of the valves on the SG gas flow line to the dump tank because of earlier detection for the pressure rise. After this modification, the design margin of the SG system will be sufficiently improved. 相似文献
33.
A new brassinolide inhibitor, named KM-01, was isolated from the culture filtrates of two fungal species, Drechslera avenae and Pycnoporus coccineus, and the structure with absolute stereochemistry was elucidated as the fatty acid ester of an eremophilane sesquiterpene, bipolaroxin, based on spectroscopic analysis, chemical degradation, and synthesis of the fatty acid. 相似文献
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De Leo R H Akimune N Blasi I Daito Y Fujita M Fujiwara SI Hayakawa S Hatori K Hosono H Ikegami T Inomata I Katayama K Katori L Lagamba S Micheletti S Morinobu T Nakagawa S Nakayama A Narita T Noro R Perrino M Pignanelli H Sakaguchi J Takamatsu A Tamii K Tamura M Tanaka A Terakawa T Tohei M Tosaki T Yamagata A Yamagoshi M Yosimura M Yosoi 《Canadian Metallurgical Quarterly》1996,53(6):2718-2731
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Mizutani A. Hatori N. Nishiyama N. Koyama F. Iga K. 《Photonics Technology Letters, IEEE》1998,10(5):633-635
We have demonstrated a GaAs (311)B vertical-cavity surface-emitting laser (VCSEL) with a threshold current as low as 250 μA, which is the lowest value ever reported for that on non-(100) oriented substrates. Also, the fabricated VCSEL shows a stable polarization state for wide during current ranges and a large polarization-mode suppression ratio over 30 dB between the [2¯33] and [011¯] axis modes at 5 mA. The electrical specific resistance of 1.2×10-4 Ω·cm-2 at the threshold was reasonably low due to carbon autodoping to AlAs in a p-type distributed Bragg reflector (DBR) 相似文献
39.
M Hatori S Takahara M Kyo Y Kokado S Nagano A Okuyama 《Canadian Metallurgical Quarterly》1998,5(6):526-533
BACKGROUND: We clinically and pathologically analyzed renal allografts from 1 9 renal transplant patients treated with tacrolimus (FK506) for more than 1 year. METHODS: Twenty-six renal allograft biopsy specimens from 1 9 renal transplant patients who underwent transplantations between 1991 and 1993 were evaluated. Thirteen biopsies were performed from stable functioning renal allografts with informed consent (nonepisode biopsy) and the other 13 were from dysfunctional renal allografts with a clinical indication for biopsy (episode biopsy). RESULTS: The main pathologic diagnoses (some overlap) were acute rejection (AR; n = 4), chronic rejection (CR; n=5), AR+CR (n =4), recurrent IgA nephropathy (n =5), normal findings (n =2), minimal-type chronic FK506 nephropathy (n = 9), and mild-type FK506 nephropathy (n = 11). Of the nonepisode biopsies, 7 and 4 biopsies showed minimal-type and mild-type chronic FK506 nephropathy, respectively. Chronic FK506 nephropathy consisted of rough and foamy tubular vacuolization (5 biopsies), arteriolopathy (angiodegeneration of the arteriolar wall; 20 biopsies), focal segmental glomerulosclerosis (4 biopsies) and the striped form of interstitial fibrosis (11 biopsies). The serum creatinine levels of patients in the mild-type chronic FK506 nephropathy group, which included 7 episode biopsies, were statistically higher than those in the minimum-type chronic FK506-nephropathy group (P< 0.001). CONCLUSIONS: This study demonstrates that chronic FK506 nephropathy consists primarily of arteriolopathy manifesting as insudative hyalinosis of the arteriolar wall, and suggests that mild-type chronic FK506 nephropathy is a condition which may lead to deterioration of renal allograft function. 相似文献
40.
Since differential-pulse-code modulation (DPCM) and orthogonal transform coding (OTC) are the most fundamental methods of high-efficiency coding (bit-reduction method), it is important to clarify the basic coding characteristics of these methods and the difference between them in order to utilize the bit-reduction method effectively. This paper theoretically as well as experimentally compares the coding efficiency of a DPCM having a two-dimensional predictor with that of a two-dimensional Hadamard transform coding method (HTC) in the intrafield coding of the NTSC composite signal. The comparison evidenced that the distinctive difference in coding characteristics between DPCM and HTC depends greatly on the power level of carrier chrominance signals. That is, it is confirmed theoretically and experimentally that the coding efficiency of the HTC is far lower than that of the DPCM in the case of a signal having a high power level carrier chrominance signal such as a color-bar signal. 相似文献