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971.
Zong W  Liu R  Sun F  Teng Y  Fang X  Chai J 《Journal of fluorescence》2011,21(3):1249-1254
To identify and eliminate the inner filter effects (IFEs), prepositive and side cells containing absorbents are fixed beside the fluorescer contained cell. In this way, excitation and emission lights can be quenched by primary and secondary outer filter effects respectively, depending on absorbent concentration and cell length. Herein the quenching of emission fluorescence caused by IFEs can be equally reduced by outer filter effects (OFEs) and the interference of IFEs was eliminated. This approach was experimentally used for identifying the interaction mode and mechanism between BSA and nanoAg. Results showed that the quenching of BSA fluorescence and synchronous fluorescence mainly attributes to IFEs, instead of static/dynamic fluorescent quenching. In view of the above, the elimination of the interference of IFEs by the design of OFEs plays an important part in the precise application of fluorescence detector.  相似文献   
972.
Wang L  Xu BB  Chen QD  Ma ZC  Zhang R  Liu QX  Sun HB 《Optics letters》2011,36(17):3305-3307
Herein, we report a facile approach for rapid and maskless production of subwavelength structured antireflective surfaces with high and broadband transmittance-direct laser interference ablation. The interfered laser beams were introduced into the surface of a bare optical substrate, where structured surfaces consisting of a micropillar array were produced by two-step laser irradiation in the time frame of seconds. A multiple exposure of the two-beam interference approach was proposed instead of multiple-beam interference to simply realize planar patterns of a high aspect ratio. Tall sinusoidal pillars were created and shaped by pulse shot number control. As an example of the application, zinc sulfide substrates were processed with the technology, from which high transmission at an infrared wavelength, over 92%, at normal incidence was experimentally achieved.  相似文献   
973.
Cu-In-O composite thin films were deposited by reactive DC magnetron sputtering at room temperature. The samples were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV/vis spectrophotometer, four-probe measurement and Seebeck effect measurement, etc. The samples contain Cu, In and O. The ratios of Cu to In and O to In increase with increase in O2 flow rates. The ratio of Cu to In is over 1 and this suggests that Cu is in excess. The obtained Cu-In-O thin films are very possibly made of rhombohedral In2O3 and monoclinic CuO. Transmittance of the films decreases with increase in O2 flow rate. The decrease in transmittance results from increase in Cu content in the films. The optical band gap of all the samples is estimated to be 4.1-4.4 eV, which is larger than those of In2O3 and CuO. The sheet resistance of the films decreases with increase in O2 flow rate. Conductivity of the films is a little low, due to the addition of Cu and the poor crystalline quality of the film. The conduction behavior of the films is similar to that of In2O3 and the conduction mechanism of Cu-In-O thin films is through O vacancy.  相似文献   
974.
In accordance with nonperturbative quantum scattering theory,we investigate photoelectron angular distributions(PADs) from above-threshold detachment(ATD) of negative ions irradiated by circularly polarized few-cycle laser fields.Electrons ejected on the polarization plane demonstrate distinct anisotropies in angular distributions which distinctly vary with the carrier-envelope(CE) phase.The anisotropy is caused by interference between transition channels;it also depends strongly on laser frequency,pulse duration,and kinetic energy of photoelectrons.Optimal emission of photoelectrons,which varies with CE phase,makes it possible to control photoelectron motion.  相似文献   
975.
Efficient passive mode locking of a diode-pumped Yb3+:LuYSiO5 (Yb:LYSO) laser is first demonstrated in experiment using a semiconductor saturable absorber mirror (SESAM), to the best of our knowledge. A stable pulse train with a repetition rate of 101 MHz is generated. The average output power of 2.13 W and the pulse duration of 3.9 ps. With a pair of SF10 uncoated prisms for dispersion compensation, we obtained pulses as short as 780 fs with center wavelength around 1042 nm, the average output power of 1.03 W and the peak power of 13.1 kW.  相似文献   
976.
A theoretical study is carried out for the cavity cooling of a Λ-type three-level atom in a high-finesse optical cavity driven by a weakly field. Analytical expressions for the friction, diffusion coefficients and the equilibrium temperature are obtained by using the Heisenberg equations, then they are calculated numerically and shown graphically as functions of the controlling parameters. For a suitable choice of these parameters, the dynamics of the cavity field interaction with the Λ-type three-level atom introduces a sisyphus cooling mechanism yielding lower temperature than the one of the two-level atom, avoiding the problems induced by spontaneous emission.  相似文献   
977.
以四(3,5-二叔丁基-4-羟基苯基丙酸)季戊四醇酯(抗氧剂1010)、Na2SO3作为乙醇胺(MEA)的氧化降解的改性剂,考察改性MEA富集模拟烟道气中CO2的效果,利用气相色谱、红外光谱分析抗氧剂1010与Na2SO3的适宜用量、比较两种抗氧剂的抗氧化性能.结果表明,抗氧剂1010和亚硫酸钠的添加量在0.15%时效...  相似文献   
978.
The morphology and ultrastructure of the alimentary canal in the adult female of the Japanese wax scale, Ceroplastes japonicus Green (Hemiptera: Coccoidea: Coccidae), was investigated using light microscopy, scanning electron microscopy and transmission electron microscopy. The results showed that the foregut was subdivided into a sclerotized pharynx and an oesophagus. A pair of salivary glands attached in the middle of the foregut. The loop-shaped midgut was narrow and longer than the foregut and its inner wall lined with a thick layer of epithelia. The hindgut was divided into a narrower ileum and a broader rectum, with the well-developed filter chamber enclosed in the anterior rectum. Malpighian tubules consisted of two brownish-yellow moniliform tubules with pores, approximately 1 μm in diameter, scattered on the outer surface and many spherical crystals inside the tubules.  相似文献   
979.
刘超飞  胡柯  胡涛  唐翌 《中国物理 B》2011,20(1):10309-010309
The perturbation of a confining trap leads to the collective oscillation of a Bose--Einstein condensate, thereby the propagation of a dark soliton in the condensate is affected. In this study, periodic perturbation is employed to match the soliton oscillation. We find that the soliton dynamics depends sensitively on the coupling between the moving direction of the trap and that of the soliton. The soliton energy/depth evolves periodically, and a relevant shift in the soliton trajectory occurs as compared with the unperturbed case. Overall, the soliton oscillation frequency changes little even if the perturbation amplitude and frequency vary.  相似文献   
980.
Temperature and strain characteristics of uniform fibre grating with tapered metal coatings have been analysed theoretically, by which adjustable chirp characteristics of such gratings are shown. Electroplating is adopted to fabricate such gratings, and the tapered metal coating is obtained by gradually drawing the fibre grating out of the solution during the process of electroplating. The gradually changing cross-sectional area of the metal coating is calculated by a newly suggested numerical method. By combining the theoretical and numerical simulation analyses, the gratings' characteristics are given at various temperatures and strains. The results obtained using such a method are also testified by experiments.  相似文献   
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