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用离子色谱法测定环境样品中甲酸、乙酸、草酸 总被引:12,自引:0,他引:12
用离子色谱法分析环境样品中甲酸、乙酸、草酸,操作简便,灵敏度较好,线性范围宽。甲酸、乙酸、草酸的检出限分别为0.02mg/L、0.10mg/L、0.04mg/L;样品加标回收率分别为93%~106%、94%~108%、92%~108%;相对标准偏差分别为1.2%、2.4%、2.7%;工作曲线的线性范围分别为0.00~30mg/L、0.00~30mg/L、0.00~50mg/L。该法可用于酸雨、大气 相似文献
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高效液相色谱法检测人尿中皮质激素水平 总被引:1,自引:0,他引:1
建立了高效液相色谱法分析测定尿中皮质激素的方法,该法可同时测定尿中醛固酮、可的松及皮质醇的水平,最低检出限为01mg/L,线性范围05~20mg/L,回收率达95%。方法简便、灵敏度较高,可作为常规手段推广应用。 相似文献
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高效液相色谱法测定水体系中N—(2,4—二甲苯基)—N‘—甲基甲脒盐酸盐 总被引:2,自引:0,他引:2
本文研究了用高效液相色谱法测定水体中单甲脒盐酸盐的分析方法,峰高定量,标准曲线的线性范围为0-1000mg/L,回收率在87%-98%之间,直接进样分析检测限为0.35mg/L。此方法已应用于细胞反应中单甲脒盐酸盐的测定。 相似文献
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研究了氯离子对化学抑制型高效离子色谱法测定亚硝酸根时的干扰。当亚硝酸根的浓度大于2.0mg/L时,5.0mg/L的氯离子不会对亚硝酸根的峰高信号产生明显的干扰;但当亚硝酸根浓度小于0.50mg/L时,即可引起正干扰。该正干扰随着Cl~-/NO~-2浓度比的增加而迅速增大,但与流动相的流速(在2.5~3.0mL/min之间)无关。还对4种可能消除氯离子干扰的方法进行了讨论。 相似文献
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离子色谱法测定NO_2~-时Cl~-的干扰及消除 总被引:3,自引:0,他引:3
研究了氯离子对化学抑制型高效离子色谱法测定亚硝酸根时的干扰。当亚硝酸根的浓度大于2.0mg/L时,5.0mg/L的氯离子不会对亚硝酸根的峰高信号产生明显的干扰;但当亚硝酸根浓度小于0.50mg/L时,即可引起正干扰。该正干扰随着Cl~-/NO~-2浓度比的增加而迅速增大,但与流动相的流速(在2.5~3.0mL/min之间)无关。还对4种可能消除氯离子干扰的方法进行了讨论。 相似文献
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高效液相色谱法测定血清中头孢噻肟浓度 总被引:3,自引:0,他引:3
用固相萃取法处理样品,以扑热息痛为内标物、甲醇-醋酸钠/醋酸缓冲溶液作流动相,采用反相高效液相色谱法测定血清中头孢噻肟的浓度。头孢噻肟和内标物的平均回收率分别为96.7%和97.7%,头孢噻肟血清浓度在10mg/L至150mg/L范围内有良好线性关系,最低检测浓度为2mg/L,日内和日间相对标准偏差分别在3.0%和4.1%以内。结果表明方法准确、简便。 相似文献
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DFT calculations have been performed to explore the aminotriazine adsorption on graphene surfaces.Relative energies,equilibrium geometries and electronic structures of monomer and dimer of aminotriazine molecules adsorbed at the surface were investigated and analyzed in details.It was found that the hydrogen atoms in the NH2 group of aminotriazine molecules are directed toward the graphene surface,and the adsorption energy increases as the NH2 group is added.The adsorbed aminotriazine molecules facilely form a dimer through the hydrogen bonding interactions,and the two aromatic rings of optimized structure of 2-amino-1,3,5-triazine(B) dimmer(denoted by B2) and melamine(D) dimmer(denoted by D2) are parallel to the graphene sheet.The large deviation of the averaged adsorption energy of B2 and D2 compared to monor adsorption may reflect the increase of π-π repulsion and the effect of hydrogen bond formation.The electronic structure analyses reveal that the formation of hydrogen bonds in melamine dimer has great influence on the adsorption mode at the graphene surface. 相似文献
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第三相界面对高分子共混物粗化过程的影响研究 总被引:8,自引:3,他引:5
共混物相分离的机理已有研究[1].但对共混物分散相的粗化过程的研究则不多见.1977年,Cahn等[2]预言第三相界面与低分子共混物之间存在的浸润作用对相分离过程应有较大影响.近年Tanaka等[3]的研究结果表明,在几何空间受限的条件下,含有小分子... 相似文献
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V. A. Ivanov V. I. Gorshkov O. T. Gavlina E. A. Ilyukhina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(11):1826-1831
The basic results on the effect of temperature on the equilibrium and thermodynamic characteristics of ion-exchange systems and the use of this effect in developing reagentless methods for ion-exchange separation are considered. 相似文献
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Posudievskii O. Yu. Konoshchuk N. V. Kukla A. L. Pavlyuchenko A. S. Linyuchev G. V. Shirshov Yu. M. Pokhodenko V. D. 《Theoretical and Experimental Chemistry》2003,39(4):219-224
The effect of the nature of the dopant on the response of a sensor array based on films of polyaniline (PAn) under the influence of the vapor of various organic solvents was studied. It was established that the main factors determining the magnitude of the response of PAn films are the morphology of the films and the accepting power of the analyte molecules (in the case of "standard" acid dopants) and also the possibility of additional donor–acceptor interaction between the analyte molecules and the dopant (in the case of heteropoly acid dopants). It was shown that with heteropoly acids as dopants of PAn it is possible to increase substantially the selectivity of the response of the sensor array. 相似文献
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Bing-Sheng Xu Jun-Wei Chen Lina Zhang Yan Fang 《Journal of Dispersion Science and Technology》2013,34(12):1816-1824
To study the structural characteristics and physical properties of droplets sitting on the inclined substrates and cylindrical surfaces, wetting experiments are conducted in different cases. The profile curves of the droplets are recorded and extracted by a CCD camera and image processing, respectively. Contact angles are figured out by fitting the profile curves and taking the derivative at the front and rear triple points. Based on the experimental results, a Surface Evolver is employed to simulate the morphological changes by minimizing the total energy of the system. Furthermore, theoretical shapes and feature parameters, including the heights and the spreading distances of the droplets, which are hard to obtain by normal experimental measurements are provided. The contact-angle hysteresis when the heavy droplet sitting on the inclined substrate is discussed. Meanwhile, the evolutions of the contour of the three-phase contact line are predicted when heavy droplets spread on the convex and concave cylindrical surfaces, respectively. This study provides a finite-element analysis method to describe the surface properties of molten droplets on different substrates, and the simulation results agree well with the experimental results. 相似文献
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本文合成了 4种螺噁嗪类化合物,并通过FTIR、1H NMR、ESI-MS对其结构进行了表征.研究了吲哚环上氮原子和噁嗪环9'位不同的取代基及溶剂化效应对其光致变色性能的影响.结果表明,吲哚环的氮原子引入体积较大的基团对螺噁嗪最大吸收波长无明显影响,然而有利于开环体的稳定性,且溴原子的引入会影响螺噁嗪的光响应性;噁嗪环... 相似文献