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111.
The distribution of speed of sound (SOS) in biomedical tissue and delay compensation (DC) have significant impact on the image quality of photoacoustic tomography (PAT). When imaging human peripheral joints, using fixed SOS and DC can only ensure that the reconstructed images are focused in a limited depth range, whereas they are defoeused at other depths, which cause severe artifacts and blurring. In this work, a linear-DC based reconstruction approach is proposed to focus the whole PAT image region. It is proved by two in vivo experiments that, compared with traditional delay-and-sum back projection algorithms, the proposed method can effectively optimize the image quality of articular tissues in PAT. 相似文献
112.
Yikai Chen Douguo Zhang Dong Qiu Liangfu Zhu Sisheng Yu Peijun Yao Pei Wang Hai Ming Ramachandram Badugu Joseph R. Lakowicz 《Laser \u0026amp; Photonics Reviews》2014,8(6):933-940
The unique optical properties of Tamm plasmons (TPs) – such as flexible wavevector matching conditions including inplane wavevector within the light line, and existing both S‐ and P‐polarized TPs − facilitate them for direct optical excitation. The Tamm plasmon‐coupled emission (TPCE) from a combined photonic–plasmonic structure sustaining both surface plasmons (SPs) and TPs is described in this paper. The sensitivity of TPCE to the emission wavelength and polarization is examined with back focal plane imaging and verified with the numerical calculations. The results reveal that the excited probe can couple with both TPs and SPs, resulting in surface plasmon‐coupled emission (SPCE) and TPCE, respectively. The TPCE angle is strongly dependent on the wavelength allowing for spectral resolution using different observation angles. These Tamm structures provide a new tool to control the optical emission from dye molecules and have many potential applications in fluorescence‐based sensing and imaging. 相似文献
113.
Enhancement factor K0, which characterizes NMR and EPR frequency shifts for Cs-129Xe, is measured for the first time. The enhancement factor r-o was measured to be (702±41) at 80 ℃ and (653±20) at 90 ℃, using the NMR frequency shift, detected by atomic magnetometer at a low magnetic field of 100 nT. This result is useful for predicting the EPR frequency shifts for Cs and the NMR frequency shifts for 129Xe in spin-exchange cells. 相似文献
114.
We measure the half-wave voltage of LiNbO 3 phase modulators in a 26-GHz wideband frequency range, and then analyze it by the phase modulation photonic peak gain linked to the interferometric demodulation. The optical interferometer is constructed with two 50:50 couplers and two fiber arms with a 1-m difference in fiber length. The photonic link gain peaks are frequency dependent, as indicated by the differential time delay in the interferometer. The procedure described is a new and practical half-wave voltage measurement method that can accurately predict the nonlinear frequency characteristics of the phase modulator. Moreover, the method can be applied to various types of LiNbO 3 phase modulators. 相似文献
115.
To investigate the effect of photodynamic therapy (PDT) with hematoporphrin monomethyl ether (HMME) on bovine immunodeficiency virus (BIV) can provide the basis theory for photoinactivation of human immunodeficiency virus (HIV). To assess the protection of HMME-PDT on the cell line Cf2Th infected with BIVR29 by 3-(4,5)-dimethylthiahiazol-2-yl-3,5-di-phenytetrazolium bromide (MTT) with power density of 5 and 25 mW/cm2 and energy density from 0.6 to 3 J/cm<'2>. To observe the inhibition of membrane fusion using a new reporter cell line BIVE by fluorescence microscope. HMME-PDT has significant protectant effects on Cf2Th-BIVR29 with both power densities, especially in the group of high power density. Fluorescent microscope shows that there is no significant difference between the group of PDT and control, which means PDT could not inhibit the BIV-mediated membrane fusion. 相似文献
116.
Linghao He Lu Yao Debin Yang Qingmin Cheng Jing Sun Rui Song 《Journal of Macromolecular Science: Physics》2013,52(12):2454-2463
Composites comprised of chitosan (CS) and multiwalled carbon nanotubes (MWCNTs) were fabricated by milling and ultrasonication dispersion methods. Scanning electron microscopy images showed homogeneous dispersion of MWCNTs throughout the CS matrix for samples prepared by either ultrasonication or milling methods. Further, the crystallinity of the CS component was found to decrease with the addition of MWCNTs, although the decomposition temperature and the storage modulus (E′) of the samples were improved. The decomposition temperature for the composite prepared by milling was 7°C higher than that by the ultrasonication. Meanwhile, the E′ decreased relatively slowly with temperature in the dynamic mechanical analysis measurements. In addition, IR analysis implied an interaction between CS and MWCNTs, which likely originated from hydrogen bonds between the amino, hydroxyl, and carboxyl groups of the two components. Compared with the ultrasonication, milling was more effective to promote the formation of the hydrogen bonds between CS and the MWCNTs and thus enhance the thermal stability of CS. 相似文献
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提出一种利用 GHZ态实现多原子缠结态的量子隐形传态方案 .当作为量子通道的 GHZ态含有一个单模高 Q腔时 ,大大地简化了量子稳形传态中的联合测量过程 相似文献