Synthesis and photoluminescence properties of wash-board belt-like ZnSe nanostructures

Washboard belt-like zinc selenide （ZnSe） nanostructures are successfully prepared by a simple chemical vapor deposi- tion （CVD） technology without catalyst. The phase compositions, morphologies and optical properties of the nanos- tructures are investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmis- sion electron microscopy （HRTEM） and photoluminescence （PL） spectroscop, respectively. A vapor-liquid mecha- nism is proposed for the formation of ZnSe belt-like structures. Strong PL from the ZnSe nanostructure can be tuned from 462 nm to 440 nm with temperature varying from 1000 ℃ to 1200 ℃, and it is demonstrated that the washboard belt-like ZnSe nanostructures have potential applications in optical and sensory nanotechnology. This method is ex- pected to be applied to the synthesis of other II-VI groups or other group＇s semiconducting materials.     

A fluorescent porous silicon-based biosensor for small molecule detection

Fluorescent porous silicon was prepared as a stable biosensor chip substrate. The aminopropyltriethoxysilane (APTES) molecules are attached in the pores of the porous silicon with a crosslink method, and when the molecules are added into the chip, the fluorescence intensity is reduced according to the concentration of the APTES. Controlled experiments are also presented with the small molecule that cannot be covalently coupled, and the results show that this kind of sensor chip has better specificity. Compared with other conventional methods, this method is simple, quick and label-free.     

Digital image biological detection technology based on the porous silicon periodic crystals film

In order to solve this problem, a new biological detection method is proposed, which makes use of the characteristics of optical transmission at the edge of the spectral band gap and sensitive to refractive index variation. When the probe light with wavelength at the edge of the Bragg band gap of porous silicon is incident on the surface of porous silicon, the change of refractive index caused by deoxyribonucleic acid (DNA) reaction in porous silicon will affect the detection light intensity transmitted from the porous silicon sensor. By analyzing the change of the average gray value of the transmitted light image, the concentration of the DNA can be obtained.     

一种多孔硅基导模共振滤波器的研究

提出了一种基于多孔硅的光栅导模共振滤波器,采用严格的耦合波理论分析方法,进行数值仿真并分析了多孔硅基导模共振滤波器的反射光谱特性.同时设计了工作在1550nm波长的窄带多孔硅硅基光栅滤波器的结构参数.研究结果表明,此滤波器具有非常高的反射率峰值,和边带抑制较高且带宽较窄的反射谱,是一种性能优异的光通信硅基滤波器件.     

多孔硅——聚合物PFTD复合膜的光致发光研究

文章采用直接浸泡法在多孔硅中嵌入了新型共轭有机聚合物聚[4-（N,N-二甲基胺丙氧基）苯-4,4’-二苯胺-9,9-二辛基芴-4,7-二噻吩-2-基-2,1,3-苯并噻二唑]（PFTD）,对比研究了多孔硅,PFTD/多孔硅,PFTD/硅以及PFTD在甲苯溶液中的光致发光特性。实验结果表明：PFTD/多孔硅复合膜光致发光强度要明显强于PFTD/硅,同时由于聚合物在固态时有效共轭程度增加导致PFTD/多孔硅复合膜的荧光光谱相对于甲苯溶液中的红光聚合物光谱有所红移。     

电解液浓度对双槽法腐蚀多孔硅的影响

设计了一种电化学双槽腐蚀装置,研究了不同电解液的浓度对制备多孔硅形貌和光学特性的影响.研究结果表明采用此装置制备的多孔硅孔洞均匀性好,并且随NaCl电解液浓度的增加,制备的多孔硅孔径呈减小的趋势,发光强度有所增强.     

Synthesis and photoluminescence properties of CdS hollow nanospheres by chemical vapor deposition

High-density CdS hollow nanospheres are successfully synthesized by a simple chemical vapor deposition technology.The crystal structure,compositional information,and morphological structure are characterized by X-ray diffraction(XRD),scanning electronic microscopy(SEM),transmission electronic microscopy(TEM),and energy-dispersive X-ray spectrometer(EDX).The results show that the as-prepared CdS hollow nanospheres have uniform size about 1-3 μm in diameter.The Kirkendall phenomenon is proposed for the formation of the CdS nanostructures.A strong emission located at 580 nm is observed.     

新型共轭聚合物PDABTh／PS复合膜的光学三阶非线性研究

采用旋转涂布法在多孔硅（PS）中嵌入新型含偶氮苯与噻吩结构单元的共轭聚合物PDABTh,制备出聚合物PDABTh／PS复合膜。采用单光束反射z扫描方法分别对PS和pDABTh／PS复合膜在532nm处的非线性折射率进行TN量。实验结果表明,复合材料三阶非线性光学效应较PS得到了明显增强,为新型共轭聚合物PDABTh／P...     

A novel biosensor with enhanced sensitivity based on grating coupled double-layered porous silicon waveguide

The enhanced sensitivity of a guided mode biosensor is analyzed by employing double-layered porous silicon grating structures. The grating-coupled waveguide structure consists of two porous silicon grating layers with different refractive indices. simulations are carried out by changing the refractive index, which is due to the binding of biological molecules on the porous silicon pore can increase the refractive index of porous silicon. The numerical results show that this novel guided mode biosensor with a double-layered grating can provide not only a very high sensitivity but also a better reflectivity characteristic.     

基于AHP与模糊数学的信息安全风险评估模型

提出了一种在信息安全风险评估中采用层次分析方法进行风险的分析,而在风险的具体计算中采用模糊数学计算的信息安全风险评估模型。探索性的提出了一种改进的方法,把层次分析法与模糊数学计算结合起来,使得风险评估的结果得以量化,经实践证明,该模型可方便地应用于信息安全风险评估,使评估结果更科学、合理。最后辅以实例说明。