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1.
采用近红外光谱(NIR)透射法对乙醇混合燃料各成分进行定量分析;其中乙醇体积分数为84.5%~98.2%,汽油体积分数0~15%;通过偏最小二乘法(PLS)建立模型,乙醇含量NIR模型校正集测定系数(R^2)为0.9969,模型校正集标准差(SEE)和预测集标准差(SEP)分别为0.23和0.38,汽油含量NIR模型校正集测定系数为0.9939,模型校正集标准差和预测集标准差分别为0.38和0.39,对含量较小的干扰物质丙酮预测结果也理想;近红外和多元校正技术可作为乙醇混合燃料中成分含量测定简单、快速方法之一。  相似文献   

2.
王勇  倪永年 《中国科学B辑》2008,38(4):347-356
摘要利用动力学分光光度法实现了对诺氟沙星和利福平的同时测定.方法基于在氢氧化钠介质中,诺氟沙星或利福平将紫红色的高锰酸钾溶液还原成绿色的锰酸钾时存在动力学速率差差异.实验采集波长范围400~750nm(间隔1nm)及时间范围0~480s(间隔5s)内的光谱-动力学数据,可观察到高锰酸钾和锰酸钾的光谱重叠,具有526、608和433nm三个最大吸收波长.实验表明,在最佳的实验条件下,诺氟沙星和利福平在该三波长处的线性范围分别为0.15~1.8mg.L^-1和0.5~6.0mg.L^-1,诺氟沙星的检出限为0.061mg.L^-1(526nm)、0.054mg.L^-1(608nm)和0.079mg.L^-1(433nm),利福平的检出限为0.119mg.L^-1(526nm)、0.258mg.L^-1(608nm)和0.283mg.L^-1(433nm).随后,采用卡尔曼滤波(KF)、主成分回归法(PCR)、偏最小二乘法1(PLS1)、偏最小二乘法2(PLS2)和径向基函数-人工神经网络(RBF—ANN)处理一组诺氟沙星和利福平的校正组溶液在三个最大吸收波长处的二维动力学数据和在t=480S时的二维光谱数据;进而采用平行因子分析法(PARAFAC)和Turker3法处理三维光谱一动力学数据.所得的模型对未知样的预报结果表明,在608nm下利用动力学数据的PLS1和在400~750nm波长范围内利用光谱.动力学三维数据的Turker3的预报结果较好.将本文提出的方法用于药物和人尿中的诺氟沙星和利福平的同时测定,与高效液相色谱法(HPLC)的结果无显著性差异.  相似文献   

3.
近红外光谱法同时测定废水中化学需氧量和生化需氧量   总被引:1,自引:0,他引:1  
采用120个废水样品的近红外透射光谱结合偏最小二乘法,分别建立了废水中化学需氧量和生化需氧量的预测模型,并对光谱数据预处理方法和异常值诊断进行了讨论。所建的废水中化学需氧量和生化需氧量的预测模型相关系数分别为0.9542和0.9652;模型的预测相对偏差分别为25.24mg·mL-1和12.13mg·mL-1;预测范围分别为28.4~528.0mg·mL-1和16.0~305.2mg·mL-1。通过对模型进行t-检验,在显著性水平大于0.05的条件下,其测定结果与标准方法的测定结果对比,两者无显著性差异。  相似文献   

4.
多元校正紫外光度法同时测定甲硝唑与维生素B6   总被引:2,自引:0,他引:2  
本文报道多元校正紫外光度法同时测定甲硝唑和维生素B6。首先在0.1mol/LHCl溶液中对甲硝唑和维生素B6两组分混合溶液进行分光光度法测定,然后将所得的重叠光谱数据经计算机采集后,分别用化学计量学方法中的偏最小二乘法(PLS)和主成分回归法(PCR)进行处理,并用于药物样品的测定,获得了较好的定量分析结果。该法甲硝唑和维生素B6的线性范围分别为1.0~28.0mg/L和1.0~28.0mg/L,检出限分别为0.568mg/L和0.364mg/L。  相似文献   

5.
同时测定水溶液中葡萄糖、果糖和蔗糖的近红外光谱法   总被引:3,自引:1,他引:2  
通过对27个葡萄糖、果糖和蔗糖水溶液的混合体系进行近红外光谱分析,建立了葡萄糖、果糖和蔗糖含量测定的偏最小二乘法(PLS)模型;葡萄糖、果糖和蔗糖的线性范围分别为0—300g/L、0—200g/L、0—300g/L,模型校正集的标准误差(SEC)分别为1.4、1.8、1.4g/L;用该模型对6个样品进行分析,葡萄糖、果糖和蔗糖含量测定的相对标准偏差(RSD)分别为1.2%、2.6%和1.8%。  相似文献   

6.
近红外反射光谱法分析玉米秸秆纤维素含量的研究   总被引:21,自引:0,他引:21  
利用近红外反射光谱分析技术和偏最小二乘回归法(PLS),通过比较不同光谱范围和光谱预处理方法,采用二阶导数光谱预处理,在7540.3-5361.1cm^-1和4882.9—4504.9cm^-1谱区内建立了近红外光谱测定玉米秸秆纤维素含量的校正模型。利用15个玉米秸秆样品对所建模型的实际预测效果进行了验证,预测值与化学值的相关系数(r)可达0.9953,最大相对误差仅为5.20。结果表明,近红外光谱技术可以快速、准确地测定玉米秸秆纤维素,该结果对玉米秸秆材料的快速鉴定和筛选利用具有重要的意义。  相似文献   

7.
采用高效毛细管电泳电导法同时分离、测定了复方维生素B片中的主要成分VB1,VB12,VB6和VC的含量。研究了运行缓冲溶液的酸度和浓度、电泳电压、进样时间等因素对电泳的影响。在优化的实验条件下:40mmol/L Tris-4mmol/L H3BO3(pH8.0)的缓冲溶液中加入0.30mmol/L CTAB(溴化十六烷基三甲基铵),分离电压为15kV,上述4组分在5min内得到良好的分离。维生素B1,B12,B6和VC的线性范围分别为5.5~1.0mg/mL;15~1.5mg/mL;1.0~0.40mg/mL和6.6~0.80mg/mL;检测限分别为0.80μg/mL,4.0μg/mL,0.50μg/mL,2.9μg/mL;5次测定峰高的相对标准偏差分别为2.2%,1.6%,3.9%,2.8%。5次测定的平均回收率分别为99%,94%,l00%,97%。  相似文献   

8.
多元校正-光度法同时测定食品中的香兰素和乙基麦芽酚   总被引:15,自引:0,他引:15  
香兰素、乙基麦芽酚在紫外区均有吸收,其吸收光谱严重重叠。在pH=2.87的B-R缓冲溶液中对香兰素和乙基麦芽酚两组分混合溶液进行光度测定,所得重叠光谱数据分别用经典最小二乘法(CLS)、偏最小二乘法(PLS)、主成分回归法(PCR)处理,并用于食品样品的测定,获得了较好的定量分析结果。香兰素和乙基麦芽酚的线性范围均为1.0~20.0mg/L;检出限分别为0.478mg/L和0.559mg/L。  相似文献   

9.
采用近红外光谱法同时测定盐酸氯丙嗪和盐酸异丙嗪。对光谱经过10种不同预处理后,分别建立了测定盐酸氯丙嗪和盐酸异丙嗪的PLS校正模型。根据模型评价参数选择最佳模型,并用该模型对未知样品进行了预测。结果显示,对浓度范围在1~13mg.mL-1的盐酸氯丙嗪和盐酸异丙嗪,其近红外的最佳数学模型的相关系数分别为0.9432和0.9670,预测模型的均方根误差(RMSEP)分别为1.05和1.11。  相似文献   

10.
以普通玉米籽粒为试验材料,应用偏最小二乘回归法建立了基于近红外光谱数据的测定玉米籽粒中淀粉含量的校正模型。校正模型的校正误差(RMSEC)、交叉检验误差(RMSECV)和预测误差(RMSEP)分别#30.31%、0.42%和0.29%,校正数据集和独立的检验数据集的预测值与实际测定值之间的相关系数分别达到0.9255和0.9310,表明所建立的校正模型具有较高的预测精度和较好的推广性,为玉米籽粒中淀粉含量的快速、无损测定提供了新的途径:  相似文献   

11.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

12.
13.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

14.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

15.
Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.  相似文献   

16.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.  相似文献   

17.
In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.  相似文献   

18.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

19.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
微量元素钒作为生物体内必需元素,经证实有很重要的生理学功能,与机体糖代谢有十分密切的关系,且能降低糖尿病动物模型的高血糖,极有可能被开发为治疗糖尿病的药物。  相似文献   

20.
Neutral nickel(II) and palladium(II) complexes bearing β-ketoiminato ligand have been synthesized. The two complexes have been investigated as catalyst for the polymerization. Using methylaluminoxane (MAO) as a cocatalyst, both complexes produce vinyl-addition polynorbornenes, but palladium(II) complex displays much higher activity up to 8.0 × 107 g/(molPd h). Furthermore, both Ni(II) and Pd(II)/MAO system can efficiently copolymerize norbornene and 5-norbornene-2-yl acetate (NB-OCOMe) in moderate yields and in relatively high molecular weights. The analyses of the product by FTIR, 1H NMR and 13C NMR spectra give the verification of vinyl addition copolymer. The copolymers show narrow molecular weight distribution and good solubility in common organic solvents.  相似文献   

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