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971.
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
972.
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
973.
Thermal entanglement in a mixed-spin Heisenberg XXZ model under a nonuniform external magnetic field
The thermal entanglement in (1/2,1) mixed-spin Heisenberg XXZ model is investigated under an external nonuniform magnetic
field. In the uniform magnetic field system, the critical magnetic field B
c and critical temperature T
c are increased by increasing the anisotropic parameter k. The degree of magnetic field b plays an important role in improving the critical temperature and enlarging the region of entanglement in the nonuniform
magnetic field system. 相似文献
974.
In order to improve the chemical stability of BaCeO3, Ti4+ was introduced into B site of BaCeO3 to modify the chemical stability. XRD test demonstrates that
\textBaC\texte0.6\textT\texti0.2\textY0.2\textO3 - d {\text{BaC}}{{\text{e}}_{0.6}}{\text{T}}{{\text{i}}_{0.2}}{{\text{Y}}_{0.2}}{{\text{O}}_{3 - \delta }} (BCTY) keeps its original pervoskite-type structure at a high doping level of 20%. After exposure in 94% N2 + 3% CO2 + 3% H2O at 700 °C for 10 h, BCTY exhibited adequate chemical stability while decomposition was found in
\textBaC\texte0.8\textY0.2\textO3 - d {\text{BaC}}{{\text{e}}_{0.8}}{{\text{Y}}_{0.2}}{{\text{O}}_{3 - \delta }} (BCY). Accordingly, the conductivity of BCTY reaches 0.0072 S/cm at 700 °C in humidified hydrogen which is a little lower
than BCY (0.0085). Besides, BCTY displayed better sintering characteristics than BCY at high temperatures and the relative
density reaches 96.4% and 94.8%, respectively. The two samples also exhibited similar thermal expansion behavior from 30 to
1,000 °C. A fuel cell with BCTY as electrolyte exhibited 244 mW/cm2 at 700 °C and the stable short-term performance further proved the stability of BCTY. 相似文献
975.
976.
977.
以局域规整聚(3-己基噻吩) (P3HT)制备了TiO2/聚合物型双层结构光伏电池.利用稳态电流-电压测试和动态强度调制光电压谱,结合差热分析、吸收光谱和荧光光谱, 研究了非晶支化聚亚乙基亚胺(BPEI)作为P3HT膜层的添加成分对TiO2/P3HT双层电池性能的影响.由于P3HT链的高结晶性,使得TiO2/P3HT界面接触不好,导致电池性能差.当在P3HT中共混重量比WBPEI/P3HT=1%—5%的BPEI时,电池性能得到显著改善;尤其是当WBPEI/P3HT= 1%时,电池表现出近0.8V的开路电压和20μA/cm2的短路电流.结果表明BPEI对电池性能的影响不是源于P3HT-BPEI共混体系光学性能的变化,而主要是由于其改变了TiO2/P3HT界面接触性能.BPEI对TiO2/P3HT界面接触有两个相互竞争的影响,这取决于P3HT-BPEI共混体系的组成.一方面,通过降低P3HT的结晶度和增强与TiO2表面的相互作用,改善P3HT链在TiO2 表面的附着;另一方面,当BPEI含量过高时,BPEI在TiO2表面的附着量将增加,反而会阻碍P3HT与TiO2表面的接触.良好的TiO2/P3HT界面接触有利于提高激子的界面分离效率、光生电子的寿命和电池效率.本文结果有望为聚合物光伏电池性能的改善提供新的认识和方法.
关键词:
聚(3-己基噻吩)
二氧化钛
共轭聚合物
光伏电池 相似文献
978.
979.
Hongxi Liu Hong Qiu Xiaobai Chen Mingpeng Yu Mingwen Wang 《Current Applied Physics》2009,9(6):1217-1222
ZnO:Al films were deposited on glass substrates at 300 K and 673 K by direct current magnetron sputtering with the oblique target. The Ar pressure was adjusted to 0.4 Pa and 1.2 Pa, respectively. All the films have a wurtzite structure and grow with a c-axis orientation in the film growth direction. The films grow mainly with columnar grains perpendicular to the substrate and some granular grains also exist in the films. The film deposited at 673 K and 0.4 Pa has the largest grains whereas that prepared at 300 K and 0.4 Pa consists of the smallest grains and is porous. The films exhibit an n-type semiconducting behavior at room temperature. The ZnO:Al film deposited at 673 K and 0.4 Pa has the lowest resistivity (3.40 × 10−3 Ω cm), the highest free electron concentration (4.63 × 1020 cm−3) and a moderate Hall mobility (4.0 cm2 V−1 s−1). The film deposited at 300 K and 0.4 Pa has the highest resistivity and the lowest free electron concentration and Hall mobility. A temperature dependence of the resistivity reveals that the carrier transport mechanism is Mott’s variable range hopping in the temperature region below 100 K and thermally activated band conduction above 215 K. The activation energy for the film deposited at 300 K and 0.4 Pa is 41 meV and that for the other films is about 35 meV. All the films have an average optical transmittance of over 85% in the visible wavelength range. The absorption edge of the film deposited at 300 K and 0.4 Pa shifts to the longer wavelength (redshift) relative to the films prepared under the other conditions. 相似文献
980.
Spectrally selective splitters with metal-dielectric-metal (MDM) subwavelength waveguides are proposed in this paper. The
method is based on the Bragg grating structure with periodically modulated MDM waveguide width, which delivers a stop band
effect for the surface plasmon propagating in the waveguide. By adding appropriate Bragg grating structure in one or more
arms of the waveguide splitters, light in a certain frequency range can be readily guided into the desired directions, as
demonstrated numerically by the finite-difference time-domain method. Dependence and optimization of the geometrical parameters
are also considered in this paper. 相似文献