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1.
研究了7-碘-8-羟基喹啉-5-磺酸(H2QSI)在乙醇存在下分光光度法测定钒(V)的最佳条件。在乙醇存在下pH4的硫酸介质中,(H2QSI)与V(V)形成了红棕色配合物,最大吸收位于506nm处,表观摩尔吸光系数εmax=2.9×10^3L·mol^-1·cm^-1,有色配合物组成为V(V):(H2QSI)=1:3。钒(V)在0-14μg/25mL符合比耳定律。本法用于钢样中的测定,结果满意。H2QSI是光度分析中的一种显色剂,近年来,8-羟基喹啉类试剂用于钒(V)的测定尚未见报道。本文研究了V(V)与H2QSI的显色反应条件及组成,在pH4的乙醇介质中,V(V)与H2QSI生成红棕色配合物,ε506nm=2.910^3L·mol^-1·cm^-1。本方法用于低碳合金钢中钒的测定,结果满意。  相似文献   

2.
用1-甲基-2-萘甲酰基替换N-苯甲酰苯基羟胺(BPHA)的苯甲酰基,合成了一种新显色剂N-苯基-1-甲氧基-2-萘甲酰氧肟酸(N-phenyl-1-methoxy-2-naphthoyl hydroxamic acid,缩写为PMNHA)。根据元素分析、差热分析、质谱分析、核磁共振、红外光谱分析,确定PMNHA的组成和结构为 。该试剂的三氯甲烷溶液能很快从2.25-4.50mol/L HCl中萃取钒(V)的紫色配合物,其配合物最大吸收在540nm,很多外来离子,特别是大量的钛不干扰钒的测定,钒含量在0-28μg·g^-1范围遵守比耳定律。我们建立了一个高选择性和简便的用显色剂PMNHA分光光度测定钒的方法。  相似文献   

3.
将具有溶致变色特性的4‘-N,N-二甲氨基黄酮基团与聚丙烯酰胺膜基体一起共价固定化在石英玻片上,制成了测定水的光导纤维化学传感器。传感是基于水对膜的荧光有强的猝灭作用。文中提出了猝灭方程。传感器具有好的可逆性和稳定性,重复测定含水4.00%和16.0%的乙醇样品的相对标准偏差分别为0.33%和0.60%,这说明传感器还具有好的重现性。传感器用于95%乙醇中水分的含量测定,结果与气相色谱法一致。  相似文献   

4.
研究了N-(2-苯基-(1,2,3-连三唑-4-甲酰基)-N′-芳基硫脲化合物的芳环、碳硫双键、连三唑与酰胺等特征红外光谱,讨论了它们随化学结构而变化的一般规律,特别详细讨论了不同取代基对远程基团特征光谱的影响。结果表明离取代基直第五个基团的特征谱带仍然受到影响。这对远程光谱的研究是很有启发意义的。  相似文献   

5.
本文根据量子力学的线性叠加原理,构造了由多模(即q模时目平态的相反态|{{-Zj}〉q及多模虚相干态|{{-Zj}〉q这两者的线性叠加所组成的一种新型的多模Schrodinger猫态光场利用新近建立的多模压缩态理论,研究了态的N次方Y压缩效应,结果发现:①当压缩阶数N=Zp且p=2m(m=1,2,3,…,…)时,态。总是恒处于N-Y最小测不准态;②当压缩阶数N=2p且p=2m+1(m=0,1,2,3,…,…)时,如果各模的初始相位,态间的初始相位差以及各单模相干态光场的平均光子数之总和等满足一定的量子化条件,则态可呈现出周期性变化的、任意阶的N次方Y压缩效应;③当压缩阶数N=2P'+1时,无论p'=2m(m=0,1,2,…,…)还是p'=2m+1(m=0,1,2,3,…,……),只要各模的初始相位满足一定的量子条件,则当两态叠加几率幅满足时,态就恒处于N-Y测不准态,始终不呈现N-Y最小测不准态和N次方Y压缩;而当时,态始终不呈现N-Y测不准态、N-Y最小测不准态和N次方Y压缩效应.  相似文献   

6.
研究新合成的水溶性光度试剂N-壬基-N′-(氨基对苯磺酸钠)硫脲(NPT)与钯(Ⅱ)的显色反应,结果表明,在pH5.8~6.6的HAc-NaAc缓冲体系中,Pd2+与NPT形成14的黄色水溶性配合后物,CTMAB对反应有明显的增敏作用,配合物的最大吸收波长位于297.6nm,表观摩尔吸光系数ε297.6=1.27×105Lmol-1cm-1,钯含量在2~11.2μg/25mL范围内服从比尔定律,50种离子不干扰测定,其灵敏度和选择性是目前测钯(Ⅱ)的最好的试剂之一。该法用于阳极泥和催化剂中钯的测定,均获满意结果。  相似文献   

7.
GDX 501-TBP萃取色谱富集分离-原子吸收光谱法测定痕量金   总被引:2,自引:0,他引:2  
以GDX501(二乙烯苯和丙烯腈的聚合物)型树脂浸渍磷酸三丁酯(TBP)为固定相,萃取色谱法富集样品中的微量金,盐酸-硫脲溶液洗脱并用原子吸收光谱法进行测定。方法的回收率在97%-105%之间,相对标准偏差为0.76%-2.3%。用于实际样品中金的测定,结果令人满意。  相似文献   

8.
本文提出了用ICP-AES直接同时测定高纯金属钕中镧、铈、镨、钐和钇的新方法。描述了在钕样品溶液中加入乙醇后对测定灵敏度的影响,乙醇量的影响以及ICP的几个主要工作参数的选择等。当样品溶液中衡土元素的总浓度为5毫克/毫升,乙醇浓度为70%(V/V)时,测定下限分别为镧0.0020%,铈0.0030%,镨0.010%,钐0.0050%和钇0.0010%其相对标准偏差为2.9-5.7%。  相似文献   

9.
乙醛在黄嘌呤氧化酶催化作用下,被空气氧化生成乙酸和过氧化氢,酶反应生成的过氧化氢氧化新吖啶酯试剂[10-甲基-9-(对甲酰苯基)吖啶羧酸酯氟磺酸盐]产生化学发光,化学发光强度与己醛浓度在一定范围内成线性关系.由此建立了一种化学发光分析新体系,用于测定乙醇含量.线性范围2.0×10-7~1.2×10-3mol/L,测定5.0×10-7mol/L乙醛,相对标准偏差为6.8%,检测限为1.2×10-7mol/L,测定环境水样中乙醇含量,取得满意结果,回收率为95~106%.  相似文献   

10.
采用微波等离子体化学气相沉积法,用高纯氮气(99.999%)和甲烷(99.9%)作反应气体,在单晶Si(100)基片上沉积C3N4薄膜,利用扫描电子显微镜观察薄膜形貌,表明薄膜由密排的六棱晶棒组成,X射线衍射和透射电子显微镜结构分析说明该薄膜主要由β-C3N4和α-C3N4组成,并且这些结果与a-C3N4相符合较好,由虎克定律近似关系式计算了α-和β-C3N4的傅里叶变换红外光谱和Raman光谱,实验结果支持C-N共价键的存在。  相似文献   

11.
ZnO nanostructures were prepared by thermal oxidation technique for applying as ethanol sensors and dye-sensitized solar cells. To improve sensitivity of the sensor based on ZnO nanostructures, gold doping was performed in ZnO nanostructures. Gold-doped with 0%, 5%, and 10% by weight were investigated. The improvement of sensor sensitivity toward ethanol due to gold doping was observed at entire operating temperature and ethanol concentration. The sensitivity up to 145 was obtained for 10% Au-doped ZnO sensor. This can be explained by an increase of the quantity of oxygen ion due to catalytic effect of gold. Also, it was found that oxygen ion species at the surface of the Au-doped ZnO sensor remained O2− as pure ZnO sensor. For dye-sensitized solar cell application, the dye-sensitized solar cell structure based on ZnO as a photoelectrode was FTO/ZnO/Eosin-Y/electrolyte/Pt counter electrode. ZnO with different morphologies of nanobelt, nano-tetrapod, and powder were investigated. It was found that DSSCs with ZnO powder showed higher photocurrent, photovoltage and overall energy conversion efficiencies than that of ZnO nanobelt and ZnO nano-tetrapod. The best results of DSSCs were the short circuit current (Jsc) of 1.25 mA/cm2, the open circuit voltage (Voc) of 0.45 V, the fill factor (FF) of 0.65 and the overall energy conversion efficiency (η) of 0.68%.  相似文献   

12.
Evanescent field absorption spectroscopy in the infrared range of coiled fiber-optic sensor has been applied to determine the low-level water content in ethanol. Principal component regression and classical least square models have been utilized to build the calibration model and predict the water concentrations. The standard errors of predictions of water concentrations in ethanol were 3.16% and 0.42% respectively. Some methods to improve the accuracy of predicted water concentration in ethanol were suggested. The predicted concentration of water is acceptably accurate and cost-effective. The study demonstrates that the coiled fiber-optic sensor based on evanescent absorption spectroscopy is a feasible technology for prediction of the low-level water content in bio-ethanol and other industries in both on-line and remote situation.  相似文献   

13.
本文研究了乙醇对ICP激发温度、气体温度、电子数密度以及易电离元素基体效应的影响,讨论了“有机ICP”的局部热平衡特性及扩张效应。  相似文献   

14.
时间延迟积分型面阵CMOS图像传感器MTF速度失配模型研究   总被引:3,自引:2,他引:1  
徐江涛  聂凯明 《光学学报》2013,33(1):104001-23
研究了时间延迟积分型面阵互补金属氧化物半导体(CMOS)图像传感器调制传递函数(MTF)速度失配特性,在分析累加级数、像素尺寸、镜头放大倍数、行周期及电机运动速度失配等影响因素的基础上,建立了MTF速度失配模型。基于现场可编程门阵列(FPGA)开发板,搭建面阵CMOS图像传感器实现线阵时间延时积分(TDI)的CMOS测试系统。实验结果表明,在光强为3lx,速度失配M(ΔV/V)<2,8级时间延迟积分与面阵成像相比,MTF值提高50%;当累加级数为8级,速度失配满足M(ΔV/V)=2的速度失配容限时,奈奎斯特频率处的MTF值下降10%,当速度失配达到M(ΔV/V)=10时,MTF值下降35%。  相似文献   

15.
《Current Applied Physics》2018,18(2):246-253
A series of pure and iron doped strontium titanate, (SrFexTi1-xO3; x = 0, 0.1 and 0.2) powders were synthesized, characterized and used to fabricate ethanol sensors for low concentration. X-Ray Diffraction (XRD) technique was used to confirm the single phase formation. Microstructural properties of the powders were investigated using scanning electron microscopy (SEM). Electrical conductivity of all the samples at room temperature (RT) was measured. Sensors were optimized for best responsiveness by varying the operating temperature from 350 °C to 500 °C.The sensor with doping x = 0.2 exhibited best sensing response at 400 °C for ethanol gas. The undoped sensor demonstrated a decrease in resistance on exposure to ethanol gas whereas Fe-doped sensors showed increase in resistance. The doping induced changeover from n to p behavior in the sensing response on doping has been investigated and corroborated with an observed shift in the Fermi level position by X-ray photoelectron spectroscopy (XPS). The disparity in gas sensing response clearly demonstrates inter-connection of multiple influencing factors such as electrical conductivity, morphology, porosity and change in chemical composition on doping. The sensors were exposed to ethanol, nitrogen dioxide, carbon monoxide, butane gases at concentration between 5 ppm and 50 ppm. The sensor exhibited much reduced relative response to all gases other than ethanol which can be utilized for wide range of applications.  相似文献   

16.
乙醇汽油是一种新型清洁燃料,燃料乙醇在乙醇汽油中的含量会影响发动机的性能。为了确保发动机的工作可靠性,需要对乙醇汽油中的乙醇含量进行快速精准检测。本文使用中红外光谱技术对采集到的乙醇汽油的光谱数据进行定量分析。首先对原始光谱数据使用多元散射校正、基线校正、一阶导数、二阶导数等预处理方法进行预处理。然后利用ELM、LSSVM、PLS对乙醇汽油中的乙醇含量建立预测模型,通过比较3种建模方法对乙醇含量的预测能力发现,PLS方法的精度比其余两种方法更高。模型决定因子R2为0.958,预测均方误差RMSEP为1.479%(V/V,体积比)。中红外光谱技术对乙醇汽油乙醇含量的快速准确检测提供了新的思路。  相似文献   

17.
We report a rapid and simple process to massively synthesize/grow ZnO nanowires capable of manufacturing massive humidity/gas sensors. The process utilizing a chemical solution deposition with an annealing process (heating in vacuum without gas) is capable of producing ZnO nanowires within an hour. Through depositing the ZnO nanowires on the top of a Pt-interdigitated-electrode/SiO2/Si-Wafer, a humidity/gas-hybrid sensor is fabricated. The humidity sensitivity (i.e., ratio of the electrical resistance of the sensor at 11–95 % relative humidity level) is approximately 104. The response and recovery time with the humidity changing from 11 to 95 % directly and reversely is 6 and 10 s, respectively. The gas sensitivity (i.e., ratio of electrical resistance of the sensor under the air to vaporized ethanol) is increased from 2 to 56 when the concentration of the ethanol is increased from 40 to 600 ppm. Both the response and recovery times are less than 15 s for the gas sensor. These results show the sensor utilizing the nanowires exhibits excellent humidity and gas sensing.  相似文献   

18.
We report a chemometric prediction of the toxicity and quality of liquor using an optofluidic sensor based upon Waveguide Confined Raman Spectroscopy (WCRS). The WCRS sensor was used to record the Raman spectra, each obtained from a 20 µl sample of a given alcoholic beverage with and acquisition time of 20 s. This was used to predict, simultaneously, both the methanol concentration (toxicity) and ethanol concentration (quality), with an accuracy of 0.1% and 0.7% by volume, respectively, using a Partial Least Squares‐based chemometric model. The model sensor is shown to be capable of identifying toxic liquors, based on the test performed on different types of liquor samples. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
采用调变的多元醇法制备了高分散碳载PtSn催化剂(PtSn/C),XRD测试结果表明金属粒子的平均粒径为2.2 nm,略小于Pt/C催化剂,而晶格参数相对增大。通过电化学原位时间分辨红外光谱研究了乙醇在PtSn/C催化剂上的吸附和氧化过程,表明线性吸附态CO(COL)是主要的乙醇解离吸附物种,导致催化剂中毒,阻止反应继续进行;当电位增大到0.3 V时,出现了乙醛和乙酸的红外吸收峰,作为乙醇解离吸附的竞争反应,乙醛和乙酸的生成有效抑制了催化剂中毒,随着电位的增大和时间的延长,生成乙酸的选择性增大;电位进一步增大至0.4 V时有微弱CO2吸收峰出现,是乙醇电氧化的最终产物,主要来自于COL的氧化消耗。根据实验结果讨论了PtSn/C催化剂上乙醇的电催化氧化机理。  相似文献   

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