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电感耦合等离子体质谱(ICP-MS)是近年发展起来的新型痕量元素分析技术,可以用于检出限为pg/ml级的痕量元素及天然同位素分析,同位素比分析及常规同位素稀释质谱分析等。所有这些应用都显示出ICP-MS在痕量元素分析领域中具有无与伦比的优点。ICP-MS进样技术一直是人们所关注的 相似文献
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固体进样石墨炉原子吸收法直接测定饲料中钴 总被引:3,自引:1,他引:2
研究了各种实验条件,建立了一种快速准确分析饲料中痕量元素的方法,适合于常规环境监测分析。特征质量7×10~(-12)g/1%吸收,回收率94~102%,相对标准偏差4.0~8.0%。 相似文献
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通过增大样品进样量的方式,样品进样量是标准进样量的10-100倍,降低了汞的检出限,从而达到了无富集直接进样测定地表水中痕量汞.其检出限为0.008μg/L;浓度为0.05μg/L和0.10μg/L左右的有证标准物质测定均值分别为0.0483μg/L和0.1016μg/L,加标回收率为92.3%和95.2%.灵敏度高,精密度好,能达到准确定量Ⅰ类和Ⅱ类地表水汞(0.05μg/L以下)的要求.对汉江湖北段水样进行测定,在较洁净的地表水分析中,氧化还原处理后与酸化水样测定结果差异不大,处理后水样结果略微增大.建议对较洁净的地表水样品将氧化还原预处理步骤省略掉,直接进样. 相似文献
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采用微波等离子体炬(MPT)作为激发光源,通过气动雾化系统进样,循环水冷凝-浓硫酸吸水装置作为去溶系统,以Ar为等离子体工作气体,建立了氩微波等离子体炬全谱仪检测矿泉水中Na, Mg, Ca, Li和Sr等五种元素的方法。详细探究了微波功率源功率、工作气流量及载气流量等实验参数对待测元素发射信号的影响,并且对这些参数进行了优化。在优化的实验条件下,对11种瓶装饮用矿泉水进行了检测,方法对Na, Mg, Ca, Li和Sr的检出限分别为4.4,21,56,11和84 μg·mL-1,相对标准偏差范围为1.30%~5.45%(n=6),加标回收率在84.6%~98.5% 之间。实验结果表明,此装置简单便捷、分析成本低;此方法分析速度快、精确度与准确度高、能够同时测定多种元素,适用于矿泉水中元素检测,为打击非法商家提供了手段,同时也为人们的饮用水质量提供了安全保障,有望用于食品安全、药品安全、临床诊断及更多领域的分析检测。 相似文献
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悬浮进样探针原子化石墨炉原子吸收法测定地质样品中铍的研究 总被引:6,自引:1,他引:5
本应用探针恒温原子化技术,系统研究了铍的分析性能,比较了不同类型石墨管和探针材料的测定效果。应用固体悬浮进样,直接测定了地质样品中的痕量铍,方法的RSD为3.3 ̄5.2%,检测限为5.1×10^-12g铍。 相似文献
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研究了使用SC-2000国产色谱仪和手动顶空进样法,对油田水中的苯及其同系物进行分离分析的可行性。优化了实验条件,以苯为测试对象,最小检测限为10ppb,相关系数为0.9997,相对标准偏差(RSD)为1.7%,且所得到的色谱图中苯、甲苯、乙苯分离效果好,具有良好的峰形,方法快速、简便、廉价且准确,可以用于油田水中苯及其同系物的分离分析。 相似文献
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《光谱学与光谱分析》2005,25(10):1626-1626
中国化学会决定于2006年10月中旬在英雄城南昌市召开“第九届全国分析化学年会暨第9届原子光谱学术会议”,并委托南昌大学负责筹办。会议将就我国自上届学术会议以来分析化学学科的新成就、新进展和加快我国分析化学学科的发展进行学术交流和讨论,热忱欢迎大家踊跃投稿和参加会议。现将有关事项通知如下:一、征文内容(1)原子光谱分析法;(2)分子光谱分析法;(3)色谱法与分离科学;(4)电分析化学法;(5)波谱法(包括顺磁、核磁共振);(6)质谱分析;(7)形态、表面及结构分析;(8)化学计量学;(9)生物分析化学;(10)环境分析化学;(11)联用方法与自动化分… 相似文献
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固体进样石墨炉原子吸收光谱测定研究(Ⅱ):镉的测定 总被引:4,自引:1,他引:3
采用自制的石墨炉微量固体进样装置,结合L'vov平台、基体改进以及预热时通入空气等技术,直接测定了部分植物、粮食、土壤与沉积物中的痕量镉。初步解决了上述试样测定中的基体干扰、背景扣除疑难问题。标样测定取得了满意的结果。变异系数6.2~11.0%;回收率93~105%。 相似文献
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面粉、米粉中铅的悬浮进样石墨炉原子吸收法测定 总被引:3,自引:0,他引:3
在食品材料的微量元素分析中。已广泛采用石墨炉原子吸收法作为测试手段,固体进样技术的发展摆脱了繁琐的样品消解过程,从而在很大程度上克服了长期以来令人头痛的化学沾污问题。然而,由于直接固体进样技术称样量小,它要求样品具有高度的 相似文献
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空浴式汽化器基础传热问题及研究现状评述 总被引:1,自引:0,他引:1
对我国空浴式汽化器的研究和使用现状进行了评述;分析了空浴式汽化器涉及的流动沸腾、凝华结霜、自然对流等传热过程及各过程之间的相互耦合关系;提出了综合研究各传热过程及相互制约关系的新思路,拟在前期工作的基础上研究管内的汽液两相流及沸腾传热过程、管外的霜层生长及导热规律,以及翅片管内外的耦合传热规律. 相似文献
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《Heat Recovery Systems and CHP》1992,12(2):143-158
Power generation with low temperature geothermal resources is not economically viable due to the poor thermal efficiency of organic Rankine cycles (ORC). A novel idea is proposed where a vapour absorption chiller (VAC) can be employed to lower the ORC condensing temperature, thus increasing its power output. This paper presents detailed analysis of a VAC that operates with water-lithium bromide to extract heat from the geothermal brine leaving the ORC vaporizer. The evaporator of the VAC serves as the ORC condenser. A computer program is coded to simulate the combined ORC-VAC performance and compare it with that of the conventional ORC. The results indicate that the ORC-VAC option would render power generation more economical. The organic fluid flow rate in the ORC per unit power output is cut by at least 50% in this case, thus reducing the ORC size and turbine cost. Moreover, even though the ORC-VAC includes more components, the total heat exchange area requirement per unit power output remains practically unchanged. 相似文献
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Kyun Young Park Jae Gil Choi Kiwhan Sung Yunsoo Kim 《Journal of nanoparticle research》2006,8(6):1075-1081
A solid-precursor vaporizer for laboratory-scale aerosol reactors has been developed and successfully tested on the synthesis of magnesium aluminate (MgAl2O4) nanoparticles by thermal decomposition of magnesium aluminum tert-butoxide (Mg[Al(OtBu)4]2), a single-source precursor, in a furnace aerosol reactor. The reactor temperature was varied from 600 to 1000°C with the precursor concentration at 6.4 × 10−6 mol/l. The atomic ratio of Al to Mg of produced particles was determined by XPS to be 2:1 and the primary particle size ranged from 28 to 55 nm. As-produced particles were all amorphous, but the particles further heated to 1000°C exhibited crystalline MgAl2O4 structures. 相似文献
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In this investigation the composite SiOx〈Ti〉 films were prepared by the thermal evaporation of a mixture of silicon oxide (SiO2) and Тi powders. The optical transmission of the films in the IR spectral range and their temperature-sensitive properties are studied. By varying the contents of the metal in vaporizer and time of evaporation it is possible to obtain SiOx〈Ti〉 layers with resistance (for monopixel of 0.8 × 1 mm) from tens kOhms to MOhms and a value of the temperature coefficient of resistance (TCR) is equal to −2.22% K−1. IR spectrum of SiOx〈Ti〉 film is characterized by a broad absorption band in the range of 8–12 μm which is associated with the Si–O–Si stretching mode.Investigations of the effect of gamma irradiation on SiOx〈Ti〉 films have shown that their temperature-sensitive properties, in particular TCR does not change up to a dose of 106 Gy.These results suggest that SiOx〈Ti〉 films can be used as materials for production of radiation-resistant thermosensitive detectors operated in radiation fields of γ-radiation and combining functions of IR-absorption and formation of an electric signal. 相似文献
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We report on a chromatic dispersion monitoring technique using a direct detection of high-speed chirped pilot tones. Unlike the previously proposed monitoring technique using amplitude-modulated (AM) and phase-modulated (PM) pilot tones, the proposed technique can discriminate the sign of accumulated dispersion. The results show that the performance of this technique could not be seriously deteriorated by polarization-mode dispersion (PMD) and self-phase modulation (SPM) since the tone frequency was small (∼2 GHz). 相似文献