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981.
Some new generalized G-KKM and generalized S-KKM theorems are proved under the noncompact setting of generalized convex spaces. As applications, some new minimax inequalities, saddle point theorems, a coincidence theorem, and a fixed point theorem are given in generalized convex spaces. These theorems improve and generalize many important known results in recent literature.  相似文献   
982.
匙玉华  刘学深  丁培柱 《物理学报》2006,55(12):6320-6325
应用经典理论并采用辛算法,计算了HF分子在啁啾激光作用下的经典解离.讨论了激光场中HF分子的解离概率随时间的变化以及考虑振动-转动能级跃迁对分子解离概率的影响.计算结果与理论分析相符,说明运用经典理论并采用辛格式计算双原子分子在激光作用下的经典解离是有效和可行的. 关键词: 啁啾激光场 经典解离 辛算法  相似文献   
983.
Acoustic signals from wild Neophocaena phocaenoides sunameri were recorded in the waters off Liao-dong-wan Bay located in Bohai Sea, China. Signal analysis shows that N. p. sunameri produced "typical" phocoenid clicks. The peak frequencies f(p) of clicks ranged from 113 to 131 kHz with an average of 121+/-3.78 kHz (n=71). The 3 dB bandwidths delta f ranged from 10.9 to 25.0 kHz with an average of 17.5+/-3.30 kHz. The signal durations delta t ranged from 56 to 109 micros with an average 80+/-11.49 micros. The number of cycles N(c) ranged from 7 to 13 with an average of 9+/-1.48. With increasing peak frequency there was a faint tendency of decrease in bandwidth, which implies a nonconstant value of f(p)/delta f. On occasion there were some click trains with faint click energy presenting below 70 kHz, however, it was possibly introduced by interference effect from multiple pulses structures. The acoustic parameters of the clicks were compared between the investigated population and a riverine population of finless porpoise.  相似文献   
984.
In order to achieve a higher lateral resolution required for ultraprecision measurement of microstructural workpieces, phase-only pupil filtering differential confocal microscopy (PFDCM), a new approach is proposed based on the differential confocal microscopy (DCM), which uses a three-zone phase-only pupil filter with lateral super-resolution capability obtained through optimized design to change the distribution of DCM three-dimensional point spread function, so that the DCM lateral resolution is therefore significantly improved while its axial resolution is slightly improved. Preliminary experimental comparison and analyses indicate that, the lateral and axial resolutions of PFDCM are better than 0.2 μm and 2 nm, respectively, when wavelength of incidence laser beam , numerical aperture of measuring lens NA=0.85, and lateral spot size with a three-zone phase-only pupil filter GT=0.65. It is therefore concluded that PFDCM is a new approach to further improvement of lateral resolution in laser probe measurement systems.  相似文献   
985.
A method employing an isosceles prism and a right-angle one is developed for loss measurement in planar waveguides. During the measuring process, the isosceles prism is fixed and the right-angle prism fixed on the waveguide slides by following the waveguide. Only by adjusting the gap thickness we can realize the loss measurement in planar waveguides. The method is demonstrated with an Ag/Na ion-exchanged waveguide fabricated on BK7 glass from AgNO3 melt diluted with NaNO3 (mass ratio 1:9), with the condition of 4 h and . The experimental results show that the method has the advantages on convenient operation, accurate results and no required end polishing.  相似文献   
986.
1,5-Dinitroaryl-1,4-pentadien-3-ones were synthesized with ultrasound irradiation in the presence of K(2)CO(3) as catalyst. The reaction mechanism and the factors influencing the product were also discussed. The present procedure is more convenient with shorter reaction time and higher yields compared with conventional methods.  相似文献   
987.
The beam-helicity asymmetry has been measured simultaneously for the reactions pepγ and pepπ 0 in the Δ(1232)-resonance region at Q 2 = 0.35(GeV/c)2. The experiment was performed at MAMI with a longitudinally polarized beam and an out-of-plane detection of the proton. The results are compared with calculations based on dispersion relations for virtual Compton scattering and with the MAID model for pion electroproduction. There is an overall good agreement between experiment and theoretical calculations. The remaining discrepancies may be ascribed to an imperfect parametrization of some γ (*) NπN multipoles, mainly contributing to the non-resonant background. The beam-helicity asymmetry in both channels (γ and π 0) shows a good sensitivity to these multipoles and should allow future improvement in their parametrization.  相似文献   
988.
Yi  Yan  Zheng  Hanshang  Mo  Xiuying  Ding  Duo  Liu  Yanfang  He  Xiaodan 《Optical Review》2023,30(1):73-81
Optical Review - Quantum dot-converted LEDs (QCLEDs) are a new type of LED device. However, the low luminous efficiency of the QCLED cannot meet the requirements for practical applications. In this...  相似文献   
989.
本文研究贮液椭圆筒在水中的横向自由振动问题,给出了贮液椭圆筒在水中横向自由振动的振型函数和固有频率的精确计算公式,结果可由计算机解出。同时指出,内外液体对椭圆筒振动的影响等效一附着于筒体上的广义分布质量.  相似文献   
990.
三维裂纹体应力强度因子的计算   总被引:1,自引:0,他引:1  
本文采用塌缩三棱柱形奇异单元的位移计算应力强度因子,给出了一个新的全三维外推公式,它是Chen和Kuang公式〔13〕的全三维推广,特例证明,它的精度比In-graffea和Manu的公式〔8〕高一阶。数值计算表明,结果稳定和对单元尺寸改变不敏感  相似文献   
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