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排序方式: 共有815条查询结果,搜索用时 15 毫秒
1.
THE FIRST EXPERIMENT OF A THz GYROTRON WITH A PULSE MAGNET 总被引:1,自引:0,他引:1
T. Idehara H. Tsuchiya O. Watanabe La Agusu S. Mitsudo 《International Journal of Infrared and Millimeter Waves》2006,27(3):319-331
A THz gyrotron with a pulse magnet has been designed, constructed and operated in FIR FU. It is developed as one of high frequency
gyrotrons included in Gyrotron FU Series. The gyrotron has already achieved the first experimental result for high frequency
operations whose radiation frequency exceeds 1 THz. In this paper, the design detail and the operation test results for sub-terahertz
to terahertz range are described. The second harmonic operation is confirmed experimentally at the expected frequency of 1.005
THz due to TE6,11 cavity mode at the magnetic field intensity of 19.0 T. 相似文献
2.
Using temperature-modulated
differential scanning calorimetry, the melting behaviour of poly(oxytetramethylene)-alt-(aromatic oligoamide) (POTM-alt-AOA)
has been studied in comparison with that of polyoxytetramethylene glycohols
(POTMGs). The apparent melting temperature of the block copolymers is found
to be less than that of the corresponding POTMGs by approximately 30°C.
The relaxation time of melting of a POTM segment has been estimated and compared
with that of POTMG. The relaxation time of POTM-alt-AOA
is slightly shorter than that of POTMG when the molar mass of the POTM segment
is 2900; however, it is longer when the molar mass is 1400. 相似文献
3.
Kojima T. Inoue E. Tsuchiya M. Ishimaru K. 《Journal of Thermal Analysis and Calorimetry》2003,72(2):737-742
TG, swelling, and viscometric studies are presented for the residues, PTHF/IPDI polymer networks, and the extracts, the linear
polymers and unreacted IPDI, after Soxhlet extraction of PTHF/IPDI reaction products. The products are obtained by reacting
PTHF with 650, 1400, (2×650+1×2900), or 2900 of molecular mass with IPDI at various concentrations in bulk. The results on
the swelling and the viscosity experiments suggest that the PTHF/IPDI reaction products have a usual expectable structure.
All the TG curves are a double stage curve. The initial stage and the last stage seem to reflect decomposition of PTHF chains
and vaporization of the remainder, IPDI, respectively. These are analyzed by a trial-and-error construction, supposing double
event behavior. The values of ratio of mass loss associated with the initial event, W01, to the mass loss associated with the last event, W02, are smaller than the expectable those. This suggests that Event 2 involves vaporization of the decomposition products of
PTHF moieties bonded to IPDI in addition to vaporization of IPDI.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
1,3-Di-tert-butylazulene reacted with highly electrophilic trifluoromethanesulfonate of N-containing heterocycles to give 5-(dihydroheteroaryl)azulene derivatives in good yield and treatment of the 5-(dihydroheteroaryl)azulene derivatives with KOH afforded 5-(heteroaryl)azulenes in excellent yield. 相似文献
5.
TG and DSC were carried out on PMAA-net-POTM in order to elucidate the relation between the heterogeneity and the thermal changes; moreover, TG and DSC were carried out on PPOTMDM and PMAA to compare the results. The onset temperature in the last stage in the TG curve of PMAA-net-POTM increases as the concentrations of DMF and POTMDM in the polymerization decrease. This is explained in terms of plasticizers effects. A single peak due to fusion of POTM chains appears in the DSC curves of most copolymers. However, it is not seen in the DSC curves of copolymers with high heterogeneity. This is explained in terms of the freezing of POTM chains by frozen heterogeneous moieties. 相似文献
6.
7.
Kim GN Kim EJ Son D Bacala A Imlay R Kirk P McNeil RR Metcalf W Cheng CP Mao ZP Yan Y Xu YT Zhu YC Abashian A Gotow K Kajino F Low E Naito F Piilonen L Childers R Darden C Lusin S Rosenfeld C Wilson S Frautschi M Kagan H Kass R Trahern CG Ko W Lander RL Maeshima K Malchow RL Higashi JR Kurihara Y Maki A Nozaki T Omori T Perez P Sagawa H Sakai Y Sugimoto Y Takaiwa Y Terada S Tsuchiya K Poling R Green J Park IH Sakamoto S Sannes F Schnetzer S Stone R Trentalange S Zimmerman D Miyano K Miyata H 《Physical review letters》1988,61(8):911-914
8.
Antiviral activity of natural occurring flavonoids in vitro 总被引:2,自引:0,他引:2
Y Tsuchiya M Shimizu Y Hiyama K Itoh Y Hashimoto M Nakayama T Horie N Morita 《Chemical & pharmaceutical bulletin》1985,33(9):3881-3886
9.
10.
Kakiuchi F Tsuchiya K Matsumoto M Mizushima E Chatani N 《Journal of the American Chemical Society》2004,126(40):12792-12793
Ruthenium-catalyzed silylation of sp3 C-H bonds at a benzylic position with hydrosilanes gave benzylsilanes. For this silylation reaction, Ru3(CO)12 complex showed high catalytic activity. This silylation proceeded at the methyl C-H bond selectively. For this silylation reaction, pyridyl and pyrazolyl groups, and the imino group in hydrazones, can function as a directing group. Several hydrosilanes involving triethyl-, dimethylphenyl-, tert-butyldimethyl-, and triphenylsilanes can be used as a silylating reagent. Coordination of an sp2 nitrogen atom to the ruthenium complex is important for achieving this silylation reaction. 相似文献