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排序方式: 共有1809条查询结果,搜索用时 15 毫秒
1.
A. Nakano T. Shimazaki M. Sekiya H. Shiozawa K. Ohtsuka A. Aoyagi T. Iwakiri Z. Mikami M. Sato Y. Sugino K. Kinoshita T. Matsuoka T. Imamura Y. Takayama K. Yamamoto 《International Journal of Hydrogen Energy》2021,46(29):15649-15659
Monitoring the temperature in liquid hydrogen (LH2) storage tanks on ships is important for the safety of maritime navigation. In addition, accurate temperature measurement is also required for commercial transactions. Temperature and pressure define the density of liquid hydrogen, which is directly linked to trading interests. In this study, we developed and tested a liquid hydrogen temperature monitoring system that uses platinum resistance sensors with a nominal electrical resistance of approximately 1000 Ω at room temperature, PT-1000, for marine applications. The temperature measurements were carried out using a newly developed temperature monitoring system under different pressure conditions. The measured values are compared with a calibrated reference PT-1000 resistance thermometer. We confirm a measurement accuracy of ±50 mK in a pressure range of 0.1 MPa–0.5 MPa. 相似文献
2.
Mitsuo Miyazawa Tomohiko Takahashi Kazuki Sakata Isao Horibe 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(7):1006-1011
BACKGROUND: The biotransformation of sesquiterpenoids, which are a large class of naturally occurring compounds, using microorganisms as a biocatalyst to produce useful novel organic compounds was investigated. The biotransformation of sesquiterpenoids, (+)‐aromadendrene ( 1 ), (−)‐alloaromadendrene ( 2 ) and (+)‐ledene ( 3 ) has been investigated using Aspergillus wentii as a biocatalyst. Results: Compound 1 was converted to (−)‐(10S,11S)‐10,13,14‐trihydroxyaromadendrane ( 4 ). Compound 2 was converted to (+)‐(1S,11S)‐1,13‐dihydroxyaromadendrene ( 5 ) and (−)‐5,11‐epoxycadin‐1(10)‐en‐14‐ol ( 6 ). Compound 3 was converted to compound 6 , (+)‐(10R,11S)‐10,13‐dihydroxyaromadendr‐1‐ene ( 7 ) and (+)‐(10S,11S)‐10,13‐dihydroxyaromadendr‐1‐ene ( 8 ). The structure of the metabolic products has been elucidated on the basis of their spectral data. CONCLUSION: Compound 1 gave only one product that was hydroxylated at C‐10, C‐13 and C‐14. By contrast, compounds 2 and 3 gave a number of products, one of which was common. The differences in oxidation of 1–3 are due to the configuration of the C‐1 position. Compounds 4–8 were new compounds. Copyright © 2008 Society of Chemical Industry 相似文献
3.
S Matsuoka K Mori O Nakano Y Yuasa Y Taguchi Y Hayabuchi Y Kuroda 《Canadian Metallurgical Quarterly》1997,156(9):704-708
Twenty-two children with chronic hepatitis serologically positive for hepatitis C virus (HCV) were treated with interferon-alpha (IFN-alpha). Liver biopsy showed chronic active hepatitis in 13 and chronic persistent hepatitis in 9 patients. A sustained clearance of HCV was observed in 8/22 children 12 months after the administration of IFN-alpha for 26 weeks, associated with normalization of HCV core antibody. Of these eight patients six had HCV genotype III and two HCV genotype II or IV. Hepatitis relapsed in seven other patients after completion of IFN-alpha with an increase in HCV core antibody titre, five with HCV genotype II, and two with HCV genotype III or IV. A second course of IFN-alpha suppressed the reactivation of HCV in all seven patients. Three of seven responders who relapsed after the first course remained negative for HCV RNA 12 months after their second course of IFN-alpha. However, the remaining four patients with HCV genotype II again relapsed after completing their second course of IFN-alpha. Seven children with the HCV genotype II resistant to IFN, including 8 weeks of IFN-beta administration, and showed no significant reduction in HCV core antibody titre. CONCLUSION: The genotype of HCV (III) and a reduction in the core antibody titre appear to be useful parameters for predicting the response to IFN-alpha therapy. 相似文献
4.
Norihito Kijima Kenichi Morie Shoichi Nagata Isao Shimono 《Journal of Low Temperature Physics》1996,105(5-6):1511-1516
A strontium tantalum sulfide, SrTa2S5, has a hexagonal structure with lattice constants of a =3.32 and c=24.1 Å. With decreasing temperature the electrical resistivity decreases monotonically and exhibits an abrupt superconducting transition at 3.16 K (midpoint). The diamagnetic susceptibility is observed below Tc. The magnetic susceptibility is nearly independent of temperature above Tc and shows Pauli paramagnetism. 相似文献
5.
Takashi Yamazaki Yoichi Takino Ryosuke Matsuoka Susumu Ito 《Electrical Engineering in Japan》1993,113(8):26-36
According to the recent analysis results of temporary ac overvoltage in the ac system connected with a frequency converter station, large-magnitude over-voltages were confirmed to occur under some special system conditions. Most of the station insulators currently used cannot withstand such overvoltages according to an evaluation based on the data obtained earlier. The necessity of tests to be done to evaluate such performance more accurately was recognized. Both power frequency and switching impulse overvoltage flashover tests were made on contaminated insulators by the method well simulating the natural wetting condition. Switching impulse flashover voltage with the waveshape having a long wavefront time of 2 ms can be well correlated with the flashover voltage characteristics of temporary ac overvoltage. Higher flashover voltage characteristics were obtained by a clean fog test method compared with those obtained by equivalent fog test method. 相似文献
6.
Evaluation of Slow Crack Growth Resistance in Ceramics for High-Temperature Applications 总被引:1,自引:0,他引:1
The slow (subcritical) crack growth (SCG) resistance of Si3 N4 and SiC ceramics has been evaluated by a stepwise loading test on bending bars precracked by Vickers indentation. Three highly refractory materials were selected for the evaluation: i.e., (1) high-purity Si3 N4 sintered by hot isostatic pressing (HIP) without additives and (2,3) α - and β - SiC pressureless sintered with B and C addition. Under the hypothesis of linear elastic behavior at high temperature, which was found satisfied in the present materials, the SCG resistance was expressed in terms of initial stress intensity factor critical for SCG failure within a predetermined lifetime. The present method was found useful in shortening the testing time and consistent with other traditional fatigue tests (e.g., static-fatigue test): It is recommended as a screening test for materials under research and development. Among the materials tested in the present study, the highest SCG resistance up to 1440°C was found in the high-purity Si3 N4 without additives. 相似文献
7.
Analysis of characteristic odors from human male axillae 总被引:7,自引:0,他引:7
Xiao -nong Zeng James J. Leyden Henry J. Lawley Kiyohito Sawano Isao Nohara George Preti 《Journal of chemical ecology》1991,17(7):1469-1492
A number of studies concerning the analysis of axillary odors have assumed that the characteristic odor produced in the axillae is due to volatile steroids and isovaleric acid. Organoleptic evaluation of Chromatographic eluants from axillary extracts was employed to isolate the region in the chromatogram where the characteristic odor eluted. The odor of the dissolved eluant was eliminated when it was treated with base, suggesting that acids make up the characteristic axillary odor. Subsequent extraction of the pH-adjusted axillary extract in conjunction with organoleptic evaluation of the Chromatographic eluant, preparative gas chromatography, and analysis by GC-MS as well as GC-FTIR showed the presence of a number of C6 to C11 straight-chain, branched, and unsaturated acids as important contributors to the axillary odor. The major odor component is (E)-3-methyl-2-hexenoic acid. Three homologous series of minor components are also important odor contributors; these consist of the terminally unsaturated acids, the 2-methyl-C6 to -C10 acids and the 4-ethyl-C5 to -C11 acids. These types of acids have not been reported previously as components of the human axillary secretions and have not been proposed previously as part of the principal odor components in this area. 相似文献
8.
Takakazu Yamamoto Kouichi ShiraishiMahmut Abla Isao YamaguchiL.“Bert” Groenendaal 《Polymer》2002,43(3):711-719
Neutral and non-doped poly(3,4-ethylenedioxythiophene), PEDOTh(Ni), and its hexyl derivative, PEDOTh-C6(Ni), have been prepared by organometallic dehalogenation polycondensation of 2,5-dichloro-3,4-ethylenedioxythiophene and its hexyl derivative with a zerovalent nickel complex. PEDOTh-C6(Ni) was soluble in organic solvents and 1H NMR data indicated that it had an Mn of 11,000. MALDI-TOF mass analysis of PEDOTh(Ni) gave Mn and Mw of about 1700 and 2400, respectively. PEDOTh-C6(Ni) showed a UV-Vis absorption peak at 546 nm in CHCl3. Electrochemical oxidation of PEDOTh-C6(Ni) started at about −0.40 V vs Ag+/Ag and gave a peak at 0.20 V vs Ag+/Ag. Chemical and electrochemical oxidation (or p-doping) of PEDOTh-C6(Ni), both in solutions and in a solid state, led to weakening of the original π-π∗ peaks and rise of new peak(s) in a region of 800-1500 nm. The p-doping of PEDOTh-C6(Ni) caused not only a decrease in the intensity of 1H NMR signals of the bridging ethylene hydrogens but also a decrease in that of the hexyl side chain, suggesting a strong interaction of the p-dopant with the side chain. NMR data of poly(3-methoxythiophene-2,5-diyl) also supported an assumption that p-doping brings about a severe change in electronic state of the substituent attached to the polythiophene main chain. PEDOTh(Ni) had a density of 1.71 g cm−3; the molecular packing mode of PEDOTh(Ni) is discussed based on the density of the polymer and its XRD data. 相似文献
9.
XIII. Yeast sequencing reports. Cloning and sequencing of the NES24 gene of Saccharomyces cerevisiae
We have cloned NES24 using a temperature-sensitive nes24-1 mutant as a host and sequenced a 3162 bp XhoI-EcoRI DNA fragment containing the NES24 gene. Computer analysis revealed that this segment contains a 1806 bp open reading frame which is needed for complementation of the nes24-1 mutation. We found SUP8 in the region upstream of the NES24 gene, placing the NES24 gene on chromosome XIII. A protein homology search indicated that NES24 encodes a new protein. The disruption of the NES24 gene resulted in temperature-sensitive growth. The sequence has been deposited in DDBJ/EmBL/GenBank data bases under Accession Number D15052. 相似文献
10.
Matsuoka F. Kasai K. Oyamatsu H. Kinugawa M. Maeguchi K. 《Electron Devices, IEEE Transactions on》1994,41(3):420-426
A guideline for n- fully gate overlapped (FOLD) structure design optimization has been studied. From the viewpoint of reliability, the greatest reduction in substrate current directly leads to the most reliable n- design for the FOLD structure. The current path modulation phenomenon due to the trapped charge at the n - extension region dominates the hot-carrier induced characteristics change for conventional lightly doped drain (LDD) structure with side-wall spacer. This phenomenon is minimized in the FOLD structure due to its higher controllability of the gate electrode than the LDD structure at the n- extension region. Furthermore, it was also confirmed that the 0.3 μm optimized FOLD structure can achieve high circuit performance at 3.3 V operation, maintaining hot-carrier resistance 相似文献