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1.
We study the nonrelativistic limit of the Cauchy problem for the nonlinear Klein-Gordon equation and prove that any finite energy solution converges to the corresponding solution of the nonlinear Schr?dinger equation in the energy space, after the infinite oscillation in time is removed. We also derive the optimal rate of convergence in . Received: 13 July 2000 / Published online: 1 February 2002  相似文献   
2.
THE FIRST EXPERIMENT OF A THz GYROTRON WITH A PULSE MAGNET   总被引:1,自引:0,他引:1  
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   
3.
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   
4.
A chemoattractant candidate named sperm-activating and attracting factor (SAAF) from the eggs of ascidian Ciona intestinalis, was synthesized from chenodeoxycholic acid in 16 steps. The present synthesis led to the unambiguous structure determination of SAAF to be (3R,4R,7R,25S)-3,4,7,26-tetrahydroxycholestane-3,26-disulfate. The synthetic pure specimen was also used to confirm the dual sperm-activating and attracting activity.  相似文献   
5.
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   
6.
Weighted Strichartz estimates with homogeneous weights with critical exponents are proved for the wave equation without a support restriction on the forcing term. The method of proof is based on expansion by spherical harmonics and on the Sobolev space over the unit sphere, by which the required estimates are reduced to the radial case. As an application of the weighted Strichartz estimates, the existence and uniqueness of self‐similar solutions to nonlinear wave equations are proved on up to five space dimensions. © 2006 Wiley Periodicals, Inc.  相似文献   
7.
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   
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A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed for the simple and rapid determination of tumor cells. The present system consists of a CCD image sensor, image memory board, personal computer, and microscope. When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis, a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored before reaction. L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation of the whole system is possible.  相似文献   
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