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The structural properties of Al isotopes are analysed using the relativistic mean field formalism with NL3 parameter set. The Glauber model technique is implemented to study the reaction dynamics for 23?28Al taking 12C as the target. The enhanced reaction cross section, high value of radius, narrow longitudinal momentum distribution and small proton separation energy of 23Al favours a proton halo structure for this nucleus. 相似文献
996.
State-of-the-art compact recirculating electron accelerators operating at intermediate energies (tens of MeV) are reviewed. The acceleration schemes implemented in the rhodotron, ridgetron, fantron, and cylindertron machines are discussed. Major accelerator components such as the electron guns, accelerating cavities, and bending magnets are described. The parameters of currently operating recirculating accelerators are tabulated, and applications of these accelerators in different processes of irradiation are exemplified. 相似文献
997.
We have demonstrated a speckle reduction method using motionless image conduits (MICs). Different experimental conditions by introducing the high-coherence HeNe laser and the low-coherence laser diode (LD) as the illumination light sources, by employing the straight MIC and the curved MIC as the speckle reduction components, and by recording speckle images without (objective speckle) and with (subjective speckle) the imaging lens mounted on the CCD camera are conducted, respectively. The most efficient speckle reduction condition is found by the combination of using the LD and the curved MIC, where the objective speckle contrast ratio is reduced from 0.7378 to 0.1725. Experimental results are discussed, and the causes for these speckle reduction efficiency changes are given. 相似文献
998.
Aimed at the complex information in videos and low detection efficiency, an actions detection model based on neighboring Gaussian structure and 3D LARK features is put forward. We exploit a double hierarchical multi-structure space–time statistical matching model (DMSM) in temporal action localization. First, a neighboring Gaussian structure is presented to describe the multi-scale structural relationship. Then, a space–time statistical matching method is proposed to achieve two similarity matrices on both large and small scales, which combines double hierarchical structural constraints in model by both the neighboring Gaussian structure and the 3D LARK local structure. Finally, the double hierarchical similarity is fused and analyzed to detect actions. Besides, the multi-scale composite template extends the model application into multi-view. Experimental results of DMSM on the complex visual tracker benchmark data sets and THUMOS 2014 data sets show the promising performance. Compared with other state-of-the-art algorithm, DMSM achieves superior performances. 相似文献
999.
Shinpei Okawa Takeshi Hirasawa Ryota Sato Toshihiro Kushibiki Miya Ishihara Toshiharu Teranishi 《Optical Review》2018,25(3):365-374
Gold nanoparticles (AuNPs) are used as a contrast agent of the photoacoustic (PA) imaging. The efficiency of AuNPs has been discussed with the absorption cross section. However, the effects of the scattering of the light by AuNPs and surrounding medium on the PA signal from AuNPs have not been discussed. The PA signals from the aqueous solution of AuNPs were examined in the numerical simulation and the experiment. In the numerical simulation, the absorption and scattering cross sections of spherical and polyhedral AuNPs were calculated by Mie theory and discrete dipole approximation. Monte Carlo simulation calculated the absorbed light energy in the aqueous solution of AuNPs. Based on the PA wave equation, the PA signals were simulated. In the experiment, the PA signal from the aqueous solution of AuNP was measured by use of a piezoelectric film and a Q-switched Nd:YAG laser operated at 532 nm. The results of the numerical simulation and the experiment agreed well. In the numerical simulation and the experiment, a single Au nanocube with 50-nm edge generated the peak value of the PA signal significantly. It was approximately 350 times and twice as large as the peak values of the spherical AuNPs with 10- and 50-nm diameters, respectively. The peak value of the PA signal depended on both the absorption and scattering coefficients of the AuNPs and the surrounding medium. The peak value increased with the scattering coefficient in a quadratic manner. The character of the temporal profile of the PA signal such as full width at half maximum depended on the scattering coefficient of the AuNPs. 相似文献
1000.
Yu-Shou Song Li-Yuan Hu Ying-Wei Hou Hui-Lan Liu Zhao-Yang Xie Ke Zhou Jia-Xing Li Ji-Ren Zhou Wen Zeng Chao-Jin Gui Jian-Song Wang Yan-Yun Yang Peng Ma Jun-Bing Ma Shi-Lun Jin Zhen Bai Mei-Rong Huang Wei-Hu Ma Ming-Hui Zhao Yuan-Jie Zhou Yong Li 《The European Physical Journal A - Hadrons and Nuclei》2018,54(3):35