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1.
李楠  阎宏涛 《分析化学》2002,30(11):1348-1351
通过理论和实验比较了分光光度法与激光热透镜光谱分析法在高散射背景下测量物质光吸收的差异。研究了在不同含量纳米TiO2的散射背景下,散射对分光光度法和热透镜光谱分析法测定耐尔蓝溶液含量的影响。结果表明,分光光度法对具有光散射性质试样的测定存在较大误差,而激光热透镜光谱分析法能较好的避免散射影响,测定结果准确。实验结果与理论分析相一致。  相似文献   

2.
采用氦-氖激光器(632.8nm)观测了铌(V)与2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚(5-Br-PADAP)和酒石酸所形成的紫蓝色三元配合物的激光热透镜效应,建立了近场激光热透镜光谱分析法测定铌的新方法。铌(V)质量浓度在0-500ng/mL范围内与热透镜信号强度呈良好的线性关系,检出限为5ng/mL。该方法已应用于钢样及铌矿样中铌的测定。  相似文献   

3.
采用毛细管为测定微池,研究了毛细管微池激光热透镜光谱分析方法。理论上给出了毛细管微池激光热透镜光谱分析表达式。探讨了毛细管微池光反射的影响及其在光路位置特征、有机溶剂增强效应等。应用毛细管微池激光热透镜光谱分析于钼蓝法测定磷和浊点萃取测定孔雀石绿。结果表明建立的毛细管微池激光热透镜光谱分析方法,具有简单易行、高灵敏度的特点,适用于微量样品的分析测定。该研究不仅对于微量样品的测定具有应用价值,而且对于激光热透镜光谱分析法在绿色分析化学中的应用具有积极的促进作用。  相似文献   

4.
激光热透镜光谱分析法同时测定铜、钴和镍研究   总被引:1,自引:0,他引:1  
基于2-(5-NO2-吡啶-2-偶氮)-1-羟基-8-氨基萘-3,6-二磺酸与铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)反应酸度的差异及热透镜信号强度的加和性,建立了激光热透镜光谱法同时测定铜、钴和镍的新方法。测定铜、钴和镍的线性范围依次为0~200ng/mL、0~200ng/mL和0~100ng/mL,检出限依次为2ng/mL,2.5ng/mL和1ng/mL。方法已用于合成样品及人发样中铜、钴和镍的同时测定。  相似文献   

5.
基于2-(3,5-二氯-2-吡啶偶氮)-5-二甲氨基苯胺(3,5-diCl-PADMA)与钯的显色反应,以激光热透镜头谱法测定了微量钯。实验表明,在强酸性介质中,Pd^2 与3,5-diCL-PADMA室温显色形成稳定的蓝色配合物,最大吸收波长位于623nm处,与所用激光器输出激光波长匹配较好,从而建立了激光热透镜光谱法测定钯的新方法。钯浓度分别在0.005-0.04mg/L和0.03-0.025mg/L范围内呈线性关系,方法灵敏度高,选择性、重现性好,用于样品测定,结果满意。  相似文献   

6.
交叉束激光热透镜光度法的研究   总被引:1,自引:1,他引:0  
激光热透镜光度法是一种高灵敏度光谱分析技术。本文用探测束非聚焦的He-Ne激光双光束交叉热透镜技术研究了影响热透镜灵敏度的几个因素,并对远场光斑截面内信号强度分布进行了测定,对实验结果进行了讨论。在正交束构型的最佳参数下,检测了1-(2-吡啶偶氮)-2-萘酚(PAN)-Co(Ⅲ)的氯仿溶液,得到最小吸光度为1.17×10~(-6),相当于1.7 ng/mL的  相似文献   

7.
催化近场激光热透镜光谱法测定痕量铱   总被引:2,自引:0,他引:2  
韩权  阎宏涛 《分析化学》2003,31(5):608-610
将近场激光热透镜光谱分析法与动力学分析法相结合.基于铱(Ⅳ)催化高碘酸钾氧化耐尔蓝A的动力学反心,建立了催化近场激光热透镜光谱法测定痕量铱的新方法,并探讨了反应机理。结果表明:铱浓度在0.05~2.4μg/L范围内呈线性关系;俭出限为6.2 x 10-12g/mL。应用该方法测定矿样中痕量铱.结果满意。  相似文献   

8.
蛋白质-钼(Ⅵ)-邻苯二酚紫-OP显色体系的研究及应用   总被引:3,自引:0,他引:3  
建立了一种测定蛋白质的蛋白质-钼(Ⅵ)-邻苯二酚紫-OP显色体系光度法,蛋白质含量在0-50.0μg/mL范围内符合比尔定律。方法已应用于尿液、血清和豆浆中总蛋白测定,加标回收率90%-108%,相对标准偏差1.8%-3.0%(n=5),检出限4.0μg/mL。  相似文献   

9.
催化激光热透镜光谱法测定铜   总被引:5,自引:0,他引:5  
阎宏涛  田欣 《分析化学》2000,28(5):559-562
基于铜催化邻苯二胺氧化反应,以激光热透镜光谱法测定微量铜,讨论了测定条件的影响。结果表明,该方法测定灵敏度高,在0.2-1.2μg/L铜(Ⅱ)浓度范围内呈线性关系,重现性及回收率实验均取得满意的结果。  相似文献   

10.
建立了一种测定蛋白质的新方法.在pH3.6的Britton-Robinson(B-R)缓冲溶液中,蛋白质与四羧基镍酞菁NiPc(COOH)4发生相互作用,使体系在λ=388nm处的共振散射(RLS)增强,并且增强的散射强度(IRLS)与蛋白质的含量成比例,据此利用四羧基镍酞菁NiPc(COOH)4为光谱探针共振散射法测定人血清中的总蛋白质,同时优化了体系光散射检测的实验参数.在最佳的实验条件下,对牛血清白蛋白(BSA)、人血清白蛋白(HSA)、人血清总蛋白(TP)的线性范围分别为0.00~1.20mg/L、0.00~1.00mg/L、0.00~1.00mg/L,相应检测限分别为5.97×10^-4mg/L、2.90×10^-4mg/L、4.76×10^-4mg/L.将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法比较,令人满意.  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

13.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

17.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

18.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

19.
20.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

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