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961.
Continuous wave (CW) operation of a c-cut Tm (5 at %), Ho (0.3 at %):YAP laser at 2132 nm wavelength were reported in this paper. In the temperature of 77 K, the Tm,Ho:YAP crystal was double end-pumped by a 21.4 W fiber-coupled laser diode (LD) at the center wavelength of 794.3 nm. Different resonator lengths and output couplers for the total pump power were tried. The resonator length was 205 mm, and the maximum CW output power of 6.17 W was acquired, corresponding to an optical-optical conversion efficiency of 28.8% and a slope efficiency of 35.6%. 相似文献
962.
Lan Yuan Wei Wei Juan Li Zhiwei Sun Hongfang Wang Xiuzhi Zhang Yueyue Chen 《Journal of nanoparticle research》2009,11(5):1219-1225
The microscopic visualization of metal nanoparticles has become a useful tool for the investigation of their applications
in cell labeling and the study of their bio-effects. In the current study, we have developed a facile method with confocal
laser scanning microscope (CLSM) to observe unfunctionalized Au nanoparticles through fluorescent channels. The sharp reflected
signal and photostable property of the metal nanoparticles makes the present method very ideal for fluorescent co-localization,
real-time imaging, and further quantitative analysis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Lan Yuan and Wei Wei contributed equally to this study. 相似文献
963.
964.
利用近红外光谱检测多层组织血氧饱和度的研究 总被引:2,自引:0,他引:2
利用近红外光谱无创检测生物组织血氧饱和状态,是一种极富研究和应用前景的检测技术,在临床检测中被广泛应用.但常规临床检测应用于指端仅反映局部血氧饱和度信息,在使用中具有局限性,信号的可信度也存在质疑.该文提出了一种采用反射式脉搏血氧饱和度检测技术检测生物多层组织氧合状况的新方法,该方法通过调节入射光强以适应解剖学中生物组织多层结构的检测.应用该方法针对手指结构的实验结果表明,随着入射光强的改变,反映血氧饱和状态的光电脉搏波信号有显著变化.结合手指解剖学分析表明,光电脉搏波信号的变化与手指的多层面组织结构相对应,反映不同层面血氧饱和状态.这一特点表明,通过此法可以针对生物组织的多层结构进行测量. 相似文献
965.
We present a novel perspective on characterizing the spectral correspondence between nodes of the weighted graph with application to image registration. It is based on matrix perturbation analysis on the spectral graph. The contribution may be divided into three parts. Firstly, the perturbation matrix is obtained by perturbing the matrix of graph model. Secondly, an orthogonal matrix is obtained based on an optimal parameter, which can better capture correspondence features. Thirdly, the optimal matching matrix is proposed by adjusting signs of orthogonal matrix for image registration. Experiments on both synthetic images and real-world images demonstrate the effectiveness and accuracy of the proposed method. 相似文献
966.
We report the laboratory experiment on a segmented mirror testbed that shows the use of a dispersed Rayleigh interferometer to phase segmented mirrors.Segment alignment of tip-tilt is fulfilled by overlapping diffraction pattern centroids of the three individual segments on the focal plane.A spherical interferometer is introduced to evaluate the performance of piston, tip-tilt sensing, and control closed-loop, and finally a total residual root-mean-square (RMS) surface error of about 45 nm is achieved, in which a typical error of about 20 nm is contributed by piston.These results demonstrate that the dispersed Rayleigh interferometer can successfully sense the piston of segmented mirrors and be used in phasing segmented telescopes under extensive studies. 相似文献
967.
Shen-Ting Zhao Ming Chen Shu-Ji Li Ming-Hai Zhang Bo-Xing Li Manas Das Jonathan C Bean Ji-Ming Kong Xin-Hong Zhu Tian-Ming Gao 《BMC neuroscience》2009,10(1):113-8
Background
Caspase-independent apoptotic pathways are suggested as a mechanism for the delayed neuronal death following ischemic insult. However, the underlying signalling mechanisms are largely unknown. Recent studies imply the involvement of several mitochondrial proteins, including endonuclease G (EndoG) and Bcl-2/adenovirus E1B 19 kDa-interacting protein (BNIP3), in the pathway of non-neuronal cells. 相似文献968.
Ying Ding Qing Yan Jing-Wen Ruan Yan-Qing Zhang Wen-Jie Li Yu-Jiao Zhang Yan Li Hongxin Dong Yuan-Shan Zeng 《BMC neuroscience》2009,10(1):35
Background
Bone marrow mesenchymal stem cells (MSCs) are one of the potential tools for treatment of the spinal cord injury; however, the survival and differentiation of MSCs in an injured spinal cord still need to be improved. In the present study, we investigated whether Governor Vessel electro-acupuncture (EA) could efficiently promote bone marrow mesenchymal stem cells (MSCs) survival and differentiation, axonal regeneration and finally, functional recovery in the transected spinal cord. 相似文献969.
Lixin Xu Jianbo Lu Wenbo Li 《The European Physical Journal C - Particles and Fields》2009,64(1):89-95
In this paper, we consider generalized holographic and Ricci dark energy models where the energy densities are given as ρ
R
=3c
2
M
pl2
Rf(H
2/R) and ρ
h
=3c
2
M
pl2
H
2
g(R/H
2), respectively; here f(x), g(y) are positive defined functions of the dimensionless variables H
2/R or R/H
2. It is interesting that holographic and Ricci dark energy densities are recovered or recovered interchangeably when the function
f(x)=g(y)≡1 or f(x)=Id and g(y)=Id are taken, respectively (for example f(x),g(x)=1−ε(1−x), ε=0or1, respectively). Also, when f(x)≡xg(1/x) is taken, the Ricci and holographic dark energy models are equivalent to a generalized one. When the simple forms f(x)=1−ε(1−x) and g(y)=1−η(1−y) are taken as examples, by using current cosmic observational data, generalized dark energy models are considered. As expected,
in these cases, the results show that they are equivalent (ε=1−η=1.312), and Ricci-like dark energy is more favored relative to the holographic one where the Hubble horizon was taken as
an IR cut-off. And the suggested combination of holographic and Ricci dark energy components would be 1.312R−0.312H
2, which is
2.312H2+1.312[(H)\dot]2.312H^{2}+1.312\dot{H}
in terms of H
2 and
[(H)\dot]\dot{H}
. 相似文献
970.
As a component of near-field scanning optical microscope (NSOM), optical fiber probe is an important factor influncing the equipment resolution. Electroless nickel plating is introduced to metallize the optical fiber probe. The optical fibers are etched by 40% HF with Turner etching method. Through pretreatment, the optical fiber probe is coated with Ni-P film by electroless plating in a constant temperature water tank. Atomic absorption spectrometry (AAS), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDXS) are carried out to characterize the deposition on fiber probe. We have reproducibly fabricated two kinds of fiber probes with a Ni-P film: aperture probe and apertureless probe. In addition, reductive particle transportation on the surface of fiber probe is proposed to explain the cause of these probes. 相似文献