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A novel nano-structured polyaniline-ionic liquid (i.e. 1-butyl-3-methylimidazolium hexafluorophosphate, BMIPF(6)) composite (BPAN) film coated steel wire was prepared by electrochemical deposition. Scanning electron microscopy images showed that the obtained porous BPAN coating consisted of nanofibers, whose diameter ranged from 50 to 80 nm. Furthermore, the novel nano-structured composite coating was very stable at relatively high temperatures (up to 350 °C) and it could be used for more 250 times without obvious decrease of the extraction efficiency. The novel BPAN coating was used for the headspace solid-phase microextraction (HS-SPME) of organochlorine pesticides (i.e. hexachlorocyolohexane, dichlorodiphenyldichloroethylene, dichlorodiphenyldichloroethane, dichlorodiphenyltrichloroethane), coupled with gas chromatography-electron capture detection (GC-ECD). The BPAN coating showed better analytical capability on the whole compared with common polyaniline (PANI) and polydimethylsiloxane (PDMS) coatings. The key parameters influencing extraction efficiency were investigated and optimized, including desorption time, stirring speed, extraction temperature, extraction time and ionic strength. The relative standard deviations (RSDs) for single fiber repeatability ranged from 2.3 to 8.7% (n=6) and the RSDs for fiber-to-fiber reproducibility (n=6) were 4.2-12.1%, respectively. The linear ranges exceeded three magnitudes with correlation coefficients above 0.99. The detection limits were 0.12-0.31 ng L(-1). The proposed method was successfully applied for the determination of organochlorine pesticides in lake water, waste water and sewage treatment plant effluent with good recoveries from 88.9 to 112.9%. 相似文献
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In this article a sensitive differential pulse stripping voltammetry technique on Nafion‐coated bismuth‐film electrode (NCBFE) was studied for the simultaneous determination of zinc, cadmium, and lead ions in blood samples at ultra trace levels. The measurement results were in excellent agreement with those obtained from atomic absorption spectroscopy. Various operational parameters were investigated and discussed in terms of their effect on the measurement signals. Under optimal conditions, calibration curves for the simultaneous determination of zinc, cadmium, and lead ions were achieved, based on three times the standard deviation of the baseline, the limits of detection were 0.09 μg L?1 for Cd(II), 0.13 μg L?1 for Pb(II), and 0.97 μg L?1 for Zn(II) respectively. 相似文献
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Benzhi Liu Xiaobin Hu Yuehua Deng Shaogui Yang Cheng Sun 《Electrochemistry communications》2010,12(10):1395-1397
Silver nanoparticle coated multi-walled carbon nanotubes (Ag/MWCNT) were prepared and used to fabricate a modified electrode. The Ag/MWCNT composites were observed by a transmission electron microscope (TEM), and the electrochemical properties of the Ag/MWCNT composite modified glassy carbon electrode were characterized by electrochemical measurements. The results showed that these composites had a favorable catalytic ability for the reduction of trichloroacetic acid (TCAA). Square wave voltammetric (SWV) technique was applied to detect TCAA. Under optimum conditions, the voltammetric determination of TCAA was performed with a linear range of 5.0 × 10? 6–1.2 × 10? 4 mol L? 1 and a detection limit of 1.9 × 10? 6 mol L? 1 (S/N = 3). 相似文献
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Lump solutions to the generalized (2+1)-dimensional B-type Kadomtsev-Petviashvili equation 下载免费PDF全文
Benzhi Cai Zhenli Wang Lihua Zhang Hanze Liu 《Journal of Applied Analysis & Computation》2020,10(3):1038-1046
Through symbolic computation with Maple, the (2+1)-dimensional B-type Kadomtsev-Petviashvili(BKP) equation is considered. The generalized bilinear form not the Hirota bilinear method is the starting point in the computation process in this paper. The resulting lump solutions contain six free parameters, four of which satisfy two determinant conditions to guarantee the analyticity and rational localization of the solutions, while the others are arbitrary. Finally, the dynamic properties of these solutions are shown in figures by choosing the values of the parameters. 相似文献
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内腔激光磁共振吸收及饱和特性 总被引:3,自引:2,他引:1
从气体激光运转特性出发,我们得到了内腔激光磁共振吸收及其无多普勒展宽饱和吸收的一阶微商信号的数学表达式.并以NO作为吸收分子研究了激光磁共振信号强度与样品气压和激光光强的关系,同时对内腔激光磁共振中无多普勒饱和吸收特性进行了详细的讨论. 相似文献
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本文概述了激光磁共振原理,实验方法和激光磁共振谱的谱线特征;并根据其实验过程、谱线特征和计算机数据采集的原理,成功地运用12位A/D板和AT/286微机完成了高于12位转换精度的数据采集和处理.同时还简介了激光磁共振实验的数据采集和处理系统的软件流程、功能和附加硬件接口原理。并以NO分子在光频为1842.816cm^-1的超精细结构谱图为例,给出本系统的工作结果。 相似文献
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NO2ν2振动带的CO2激光磁共振垂直谱的观测 总被引:5,自引:5,他引:0
采用高灵敏度、高分辨率激光磁共振光谱(LMR)方法,使用CO2激光器测量了分子NO2v2振动带的垂直谱(△MJ=±1).观测到了前人没有测过的新谱,在22支激光谱线下新获得100支塞曼(Zeeman)跃迁谱线。 相似文献
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