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71.
FEI Qiang WANG Chunyu WANG Baojun XU Hui LI Guanghua HUAN Yanfu SHAN Hongyan FENG Guodong 《高等学校化学研究》2014,30(3):379-382
A novel water-soluble porphyrin[5,10,15,20-tetra(3-ethoxy-4-hydroxy-5-sulfonate)phenyl porphyrin, H2TEHPPS] was designed and synthesized, which could be used as a potential fluorescence sensor to detect temperature changes. The studies were performed in solution phase and the concentration of H2TEHPPS was 2.0×10^-5 mol/L. The optical properties of H2TEHPPS were investigated based on the UV and fluorescence spectra. The results show that the fluorescence intensity of H2TEHPPS is directly proportional to temperature in the range of 293-353 K So H,TEHPPS can be used as a molecular temoerature sensor in biomedical and other fields. 相似文献
72.
为了改善分子印迹传感器的灵敏度,在四丁基高氯酸铵的支持电解质溶液中,以甲基丙烯酸为功能单体,马来松香丙烯酸乙二醇酯为交联剂在纳米氧化铜修饰过的玻碳电极上电聚合了一种苯巴比妥(PB)识别性能的分子印迹传感膜.采用循环伏安(CV)法、差分脉冲伏安(DPV)法及交流阻抗(EIS)法对这种纳米氧化铜修饰过的印迹及非印迹电极的电化学性能进行了研究,结果显示纳米氧化铜修饰过的印迹及非印迹电极的电化学性能完全不同.X射线衍射(XRD)证实纳米粒子为氧化铜.采用扫描电镜(SEM)对纳米氧化铜修饰过的印迹传感器的形貌进行分析,发现纳米氧化铜分散在电极表面,改善了修饰印迹传感器的识别点.差分脉冲伏安法(DPV)表明苯巴比妥的浓度在1.0×10-8-1.8×10-4mol·L-1范围内呈现良好的线性关系(线性相关系数R=0.9994);检出限2.3×10-9mol·L-1(信噪比(S/N)=3).研究结果表明纳米氧化铜修饰过的印迹传感器具有较高灵敏度及选择性.此印迹传感器能用于实际样品中苯巴比妥的检测,加标回收率在95.0%-102.5%. 相似文献
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75.
CuS/TiO2纳米管异质结阵列的制备及光电性能 总被引:1,自引:0,他引:1
利用水热反应制备了CuS/TiO2纳米管异质结阵列,采用场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)和X射线衍射谱(XRD)等手段表征了异质结阵列的表面形貌和晶体结构.电流-电压曲线结果表明,CuS/TiO2纳米管异质结阵列具有明显的整流效应.根据表面光电压谱和相位谱,在376~600 nm之间,CuS/TiO2纳米管异质结阵列表现为p型半导体特征,电子在表面聚集;在300~376 nm之间表现为n型半导体特征,空穴在表面聚集;在376 nm处异质结阵列的表面光伏响应为零.CuS/TiO2和CuS/ITO之间界面电场的不同导致异质结在不同波长范围内表面电荷聚集的差异.光电化学性能测试发现,以CuS/TiO2纳米管异质结阵列为光阳极组成的光化学太阳电池,在大气质量AM 1.5G,100 mW/cm2标准光强作用下具有0.4%的光电转换能力. 相似文献
76.
差动式光纤微小角度传感器 总被引:1,自引:0,他引:1
采用双面反射调制技术,设计了双光纤差动式光纤微小角度传感器.动态范图±10’,分辨率1",精度可达3".可用于各种非接触微小角度的测量场合. 相似文献
77.
Leila Saedi Zahra Javanshir Salah Khanahmadzadeh Maryam Maskanati Milad Nouraliei 《Molecular physics》2020,118(7)
ABSTRACTDensity functional theory calculations were used to investigate the potential application of an AlN nanocluster in the detection of H2S, COS, CS2 and SO2 gases. In overall, the order of strength of interaction of these gases with the nanocluster is as follows: SO2 (Ead?=??17.6?kcal/mol)?>?H2S (Ead?=??14.0?kcal/mol)?>?COS (Ead?=??8.4?kcal/mol)?>?CS2 (Ead?=??4.5?kcal/mol). This indicates that by increasing the electric dipole moment, the adsorption energy becomes more negative. We found that the Al12N12 nanocluster may be a promising work function-type sensor for SO2 gas among the studied gases. Also, it is an electronic sensor for both SO2 and CS2 gases but selectively acts between them because of their different effects on the electrical conductivity. It is neither work function-type nor electronic sensor for H2S and COS gases. The AlN nanocluster benefits from a short recovery time about 7.7?s and 18.0?ms for desorption of SO2 and CS2 gases from its surface at room temperature, respectively. It is also concluded that this cluster can work at a humid environment. 相似文献
78.
Linear unbiased full-order state estimation problem for discrete-time models with stochastic parameters and additive finite energy type disturbance signals is reformulated in terms of linear matrix inequalities. Two estimation problems that are considered are the design for mean-square bounded estimation error and the design for the mean-square stochastic version of the suboptimal H∞ estimator. These two designs are shown to apply to both the estimation with random sensor delay and estimation under observation uncertainty. 相似文献
79.
This article presents a review of the strategies that have been both demonstrated and proposed for the multiplexing of multiple noninterferometric optical fiber point sensors to form a sensor network. The focus, which avoids consideration of interferometric sensor types, enables discussion of conventional multiplexing tech niques, namely, spatial, time division, frequency division, and wavelength division prior to dealing with combined or hybrid schemes, which exhibit the potential for increased multiplexing gain. Specific advantages and potential drawbacks of the different strategies are provided together with an indication of the number of point sensors that each multiplexing scheme can support. 相似文献
80.