Ultrafast optical probe of coherent acoustic phonons in Co_2MnAl Heusler film

In this work, pronounced oscillations in the time-resolved reflectivity of Heusler alloy Co_2MnAl films which are epitaxially grown on Ga As substrates are observed and investigated as a function of film thickness, probe wavelength,external magnetic field and temperature. Our results suggest that the oscillation response at 24.5 GHz results from the coherent phonon generation in Co_2MnAl film and can be explained by a propagating strain pulse model. From the probe wavelength dependent oscillation frequency, a sound velocity of(3.85±0.1)×10~3m/s at 800 nm for the epitaxial Co_2MnAl film is determined at room temperature. The detected coherent acoustic phonon generation in Co_2MnAl reported in this work provides a valuable reference for exploring the high-speed magnetization manipulation via magnetoelastic coupling for future spintronic devices based on Heusler alloy films.     

A Temperature-Insensitive Amplified Spontaneous Emission Broadband Source Based on Er-Doped Fiber

To obtain a stable amplified spontaneous emission(ASE) source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperatures.We optimize the structure of the ASE source to flatten the ASE spectrum, and study the output characteristics in terms of output power and optical spectrum under different pump powers. Then the performance of the ASE source is investigated in the temperature range from-18.9°C to 50°C. A stable-power and flat-spectrum ASE source can be obtained by structural optimization and pump control.     

阿米卡星与碲化镉量子点和牛血清白蛋白所形成的复合物之间的相互作用

以3-巯基丙酸为稳定剂,聚乙烯吡咯烷酮为表面活性剂,采用水热法合成了具有优异光学性质的碲化镉量子点.量子点与牛血清白蛋白(BSA)结合使荧光强度明显增大.对BSA测定的线性范围为0.68～13.6 mg·L-1,检出限为0.26 mg·L-1.阿米卡星对碲化镉量子点-BSA复合物的荧光有明显猝灭作用,荧光猝灭程度与其浓度呈线性关系.结果表明为静态猝灭,阿米卡星与BSA按物质的量比1比1结合,结合常数为6.47×103L·mol-1.用圆二色光谱技术探讨了阿米卡星对BSA构象的影响.     

水溶性CdTe量子点的合成及其用于荧光猝灭法测定肌红蛋白

以3-巯基丙酸为稳定剂,合成了具有特殊光学性质的水溶性CdTe量子点,其最大发射波长位于544 nm.利用荧光光谱、紫外可见光谱及圆二色光谱法系统的研究了CdTe量子点与肌红蛋白(Mb)二者结合前后体系光谱的变化,从而证实了CdTe量子点与Mb之间静电结合反应的特征.在pH 7.0的PBS缓冲液中,用CdTe量子点作为荧光探针研究了肌红蛋白与量子点的相互作用,并基于肌红蛋白对CdTe量子点有显著的荧光猝灭作用,建立了肌红蛋白的快速检测方法.在最佳实验条件下,该体系荧光强度的猝灭程度(△F)与肌红蛋白质量浓度呈良好的线性关系,线性范围为0.3～24 μg/mL,检出限为0.13 μg/mL.该方法已对合成样品中肌红蛋白进行检测,并用于人体尿样中肌红蛋白的测定.     

CdTe/CdS量子点共振瑞利散射光谱法测定细胞色素C

以3-巯基丙酸为稳定剂,合成了具有特殊光学性质的水溶性核壳型CdTe/CdS量子点.基于细胞色素C对该量子点的共振瑞利散射有显著的增强作用,建立了一种快速检测细胞色素C的方法.在pH 7.0的磷酸盐缓冲液(PBS)中,量子点在385 nm波长处的共振瑞利散射的增强与细胞色素C浓度呈线性关系,线性范围为0.036～1.31 mg·L-1,检出限为10.8 μg·L-1.方法已用于人体血清中细胞色素C含量的测定,并用标准加入法测得方法的回收率在90.4%～933.2%之间.     

CdTe/CdS量子点-蛋白质与头孢曲松钠的相互作用

以3-巯基丙酸为稳定剂,采用水热法合成了具有优异光学性质的CdTe/CdS核壳型量子点,量子产率为13.8%。量子点与牛血清白蛋白(BSA)偶联后荧光强度明显增大。通过测定荧光强度确定了偶联的最佳反应条件:pH7.4,反应温度37℃,反应时间40min。研究了溶液pH值和NaCl浓度对量子点及量子点-BSA溶液荧光强度的影响。对牛血清白蛋白测定的线性范围为1.1~19.5mg/L;检出限为0.47mg/L。头孢曲松钠对量子点-BSA的荧光有明显猝灭作用,荧光猝灭程度与其浓度有良好的线性关系。实验结果表明为静态猝灭,头孢曲松钠与BSA按1∶1结合,结合常数为6.31×103L/mol。用圆二色光谱技术探讨了其对BSA构象的影响。