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991.
Detection of trace-level hydrogen sulfide(H2 S) gas is of great importance whether in industrial production or disease diagnosis.This research presents a novel H2 S gas sensor based on integrated resonant dual-microcantilevers which can identify and detect trace-level H2 S in real-time.The sensor consists of two integrated resonant microcantilever sensors with different functions.One cantilever sensor can identify H2 S by outputting positive frequency ... 相似文献
992.
针对海杂波背景下小目标检测对海情依赖性强的问题, 本文采用分数布朗运动模型对实测海杂波建模, 结合多重分形去势波动分析法确定分形参数, 分析了海杂波的单尺度、多重分形特性. 在单尺度分形的基础上, 利用表征海杂波分形特征的分数维和Hurst指数构建了分形差量, 提出了基于分形差量的小目标检测方法;在多重分形基础上, 比较了两种海杂波的高尺度多重分形特性. 结果表明, 当尺度q > 10时, 纯海杂波的多重分形参数H(q) < 0, 而存在小目标的H(q) > 0, 此差异性为高尺度分形参数的海杂波背景小目标检测提供了判定依据. 所研究的两种方法均能实现不同海情下的小目标检测. 相似文献
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997.
This article describes the influence of bovine serum albumin (BSA) as an additive on the capillary electrophoresis–potential gradient determination of five quinolones, enoxacin, norfloxacin, ofloxacin, fleroxacin, and pazufloxacin. With 10 mg/L of BSA present in the buffer of 30 mM Tris and 3 mM phosphoric acid at pH 9, the detection limits of the five quinolones were in the range of 0.24–0.68 mg/L, i. e. 5.8–16.5‐fold lower than those obtained with the buffer devoid of BSA, and the analysis time was shortened. We suggest that the inner wall‐adsorbed BSA suppresses the adsorption of quinolones and simultaneously enhances the electroosmotic flow rate. Our experiments indicated that adopting the potential gradient detection technique could eliminate the interference of the UV‐active proteins on the detection of quinolones that would occur with conventional optical detection, and therefore offer high detection sensitivity. As a demonstration, the method was applied to the determination of QNs in fortified chicken muscle sample with satisfactory results. 相似文献
998.
我们利用稀土直接掺杂工艺 ,通过向带隙宽为 4~ 5eV的ⅡA ⅥA族化合物中掺入稀土离子Eu、Sm ,合成了电子俘获材料 (ETM ElectronTrap pingMaterial)CaS :Eu ,Sm。该材料具有红外上转换和光存储特性 ,其红外响应光谱宽 ( 0 .8~ 1 .6μm)、量子转换效率高达 76% [1 ,2 ] 、热稳定性好、使用方便 (室温下工作 ,不需制冷 )、造价低 ,并且具有“常光充能”特性 ,即不需紫外线预激发就能在室温下将红外光 ( 0 .8~ 1 .6μm)直接转换为醒目的可见红光 ,是一种优良的红外探测材料 ,利用该材料制作的… 相似文献
999.
Time response of avalanche photodiode (APD) is very important in photon counting systems, and there are many models for circuit simulation. But these studies generally based on the carrier rate equations of steady-state condition, disagree with the single-photon-indicate condition. In this paper, a time response function based on an integration of APD’s sub-domain carriers for reach-through APD arising from a single photo-carrier is derived. The analytical results are shown to be in good accord with experimental results. 相似文献
1000.
Tadashi Nishio Rie Suzuki Yuko Tsukada Hideko Kanazawa Teruo Okano Takako Miyabe-Nishiwaki 《Journal of chromatography. A》2009,1216(44):7427-7432
A new method for the quantitative analysis of monkey serum propofol, which is widely used as an anaesthetic agent, was developed by utilizing a temperature-responsive polymer of N-isopropylacrylamide (NIPAAm) and butyl methacrylate (BMA) as the stationary phase of HPLC–fluorescence detection. This poly(NIPAAm-co-BMA) copolymer undergoes a reversible phase transition from a hydrophilic to a hydrophobic microstructure when triggered by change in the temperature. Also this chromatographic system is possible to separate the analytes by using only water as a mobile phase. A pretreatment of the serum (80 μL) was only solid-phase extraction, and the recovery rate of propofol and internal standard was more than 77%, respectively. This method covered the calibration range from 0.5 μg/mL to 10 μg/mL and allowed a reproducible quantification of the serum propofol in administrated monkey serum. The intra- and inter-assay relative standard deviations were less than 14.1%. In addition, there was good relationship of the quantification values between the developed method and the widely used reversed-phase HPLC method. Our developed method has proven to be useful for a simple analysis of propofol in clinical practice, because the avoidance of complicated mobile phase preparation was possible, and only temperature changing could regulate the retention time of the analyte. In addition, by using water instead of fossil fuel, it is the ideal analytical method according to green chemistry. 相似文献