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281.
本文叙述了用于光通信快速、高辐射度GaAs/GaAlAs双异质结发光管的性能.其电带宽大于60MHz,光带宽在100MHz以上.在200mA辐射度为1017W/cm2·sr.尾纤输出超过160μw(NA=0.2).分析和讨论了影响辐射输出和调制能力的诸因素,并选取了最佳折衷方案.  相似文献   
282.
283.
单重态氧发生器出口气流中水汽含量的光谱测量法   总被引:1,自引:1,他引:0  
水汽的含量是化学法单重态氧发生器(SOG)的重要性能参数之一,因为它不仅对O_2( ̄1△)有猝灭作用,而且在氧碘化学激光器(COIL)光腔中对I ̄*也有严重猝灭作用。因此测控SOG出口处的水汽含量有重要意义。本实验采用光谱强度比较法测量SOG中的水汽含量,利用OMA-3的二维扫描积累功能,可对不同测点的光谱进行同时扫描积累,从而可以对SOG的数个测点同时进行水汽含量测定。测试精度可达±10%。  相似文献   
284.
In this paper we study the Cauchy problem for cubic nonlinear Schrödinger equation with space- and time-dependent coefficients on ∝m and \(\mathbb{T}^m \). By an approximation argument we prove that for suitable initial values, the Cauchy problem admits unique local solutions. Global existence is discussed in the cases of m = 1, 2.  相似文献   
285.
采用水热合成法制备含钛MCM-48型中孔分子筛系列催化剂,用IR和XRD等技术对催化剂进行了表征,对α-二十碳醇氧化制α-二十碳酸反应进行了研究,对目的反应的催化性能进行了评价,并确定出反应的最佳温度和反应时间,结果表明,添加适量的Ti可提高α-二十碳酸的收率。用IR技术对目的产物进行跟踪分析,所得结果与化学检测结果一致,将反应产物的收率与分子筛催化剂的L酸进行了关联。  相似文献   
286.
A novel comb‐like derivative CPEG‐g‐DNQ was prepared by incorporating light responsive 2‐diazo‐1,2‐naphthoquinone (DNQ) groups into the structure of comb‐like poly(ethylene glycol) (CPEG). DLS and TEM results showed that CPEG‐g‐DNQ self‐assembled into spherical micelles with an average size of about 135 nm in water. Upon exposure to light, the micelles could be disrupted because of the conversion of hydrophobic DNQ to hydrophilic 3‐indenecarboylic acid. Additionally, hydrophobic coumarin 102 was successfully loaded into the micelles and photo‐induced ON‐OFF release was demonstrated by fluorescence spectroscopy. MTT assay revealed that the micelles are biocompatible. These photo‐responsive micelles might have great potential for controlled release of hydrophobic drugs.

  相似文献   

287.
陈峻  刘正东  郑军  庞玮  尤素萍 《中国物理 B》2010,19(4):44201-044201
This paper studies the effects of vacuum-induced coherence(VIC) in a four-level atomic system.The effects of VIC lead to the coherent hole burnings exhibited in the system at some certain points of the Rabi frequency.This is also the reason for the enhancement of the coherent population trapping.In addition,optical bistability occurs in the evolution curves of absorption versus the phase of Rabi frequencies.  相似文献   
288.
Nanocrystals of the fluorogenic precursor fluorescein diacetate (FDA) were applied as labels in order to improve on the assay sensitivity achieved in our previous studies. Each FDA nanocrystal can be converted into ∼2.6×106 fluorescein molecules, which is useful for improving immunoassay sensitivity and limits of detection. NeutrAvidin was simply adsorbed onto the surface of the FDA nanocrystals, which were coated with distearoylglycerophosphoethanolamine (DSPE) modified with amino(poly(ethylene glycol))(PEG(2000)-Amine) as an interface for coupling biomolecules. This can be applied to detect different kinds of analytes that are captured by corresponding biotinylated biomolecules in different bioanalytical applications. The applicability of the NeutrAvidin-labeled nanocrystals was demonstrated in an immunoassay using the labeled avidin–biotin technique. Biotinylated antibody and FDA-labeled avidin were applied to the assay sequentially. The performance was compared with the traditional sandwich-type assay for mouse immunoglobulin G detection. Following the immunoreaction, the nanocrystals were released by hydrolysis and dissolution instigated by adding a large volume of organic solvent/sodium hydroxide mixture. The limit of detection was lower (by a factor of 2.5–21) and the sensitivity was (3.5–30-fold) higher than immunoassays using commercial labeling systems (FITC and peroxidase). This study shows that using fluorescent nanocrystals in combination with the avidin–biotin technique can enhance assay sensitivity and provide a lower limit of detection without requiring long incubation times as in enzyme-based labels.  相似文献   
289.
The dinuclear complex {[mu-kappa(1),kappa(3)-B(mim(Bu(t)))(3)]Pd}(2), which features a Pd-->B dative bond, may be obtained by the reaction of [Tm(Bu(t))]K with Pd(OAc)(2); treatment of {[mu-kappa(1),kappa(3)-B(mim(Bu(t)))(3)]Pd}(2) with PMe(3) affords the mononuclear boratrane derivative [kappa(4)-B(mim(Bu(t)))(3)]Pd(PMe(3)), for which a molecular orbital analysis indicates that the palladium center possesses a d(8) configuration.  相似文献   
290.
We have studied the microstructure property of InN epitaxial films grown on ZnO substrate by plasma-assisted molecular beam epitaxy. We found that the In2O3 compound was produced on ZnO substrate and many pits were formed on the InN films when InN was directly grown on ZnO substrate with the N/In flux ratio less than 40. We demonstrated that the quality of InN film was significantly improved when the In2O3 layer was used as a buffer to prevent the reaction between In and the ZnO substrate.  相似文献   
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