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ICP-MS法测定土壤中金属元素 总被引:1,自引:0,他引:1
在微波条件下,采用HCl-HF-HNO3-H2O2体系消解土壤样品,使用ICP-MS法对其中几种金属元素的含量进行测定。设计了适当的实验方法,选择了合适的实验条件,并与ICP-AES法的测定结果进行了对比,最后与标准物质的参考值比较。实验结果表明,样品中的Cr、Co、Ni、Mn、Cu、Pb、Zn、Mo、Cd的测定值与标准值一致,使用这两种分析方法测定经微波消解的样品,结果均令人满意,但不同方法测定不同元素各有优势。可为多金属岩石矿物的分析测试提供方法经验和数据参考。 相似文献
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本实验选用邻苯二甲酸二丁酯为内标物,采用内标标准曲线法,选择两种不同的色谱柱对驱蚊液中的驱蚊酯定量方法进行比较。实验结果表明,选用AE.OV-1301色谱柱,该方法的检出限为0.00073mg·mL-1,样品加标回收率为97.1%~98.6%,重复性为0.200%,在实际样品双平行测定中,其相对偏差为0.17%~0.50%;选用SE-30色谱柱,该方法的检出限为0.00090mg·mL-1,样品加标回收率为92.5%~94.8%,重复性为0.217%,在实际样品双平行测定中,其相对偏差为0.37%~0.52%。结果表明,选用AE.OV-1301色谱柱对驱蚊酯进行定量分析时,结果优于SE-30色谱柱。该方法简单,快速,灵敏度高,结果准确、可靠,可用于驱蚊喷雾中驱蚊酯的测定。 相似文献
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本研究分别采用FIA法和传统分光光度法测定水中不同浓度含量挥发酚并进行了多组基体加标实验,结果表明对于不同浓度水平及不同基体加标样品的测定,2种方法的精密度和准确度均符合标准相关要求,对检测结果进行配对t检验,两种方法测定结果无显著差异,但流动注射法相比传统分光光度法有更高的精密度和更宽的线性范围,且检测方法更简便、快捷,安全性和自动化程度更高,更利于第三方检测机构大批量高效测定样品。为更科学、合理的表示FIA法检测水中挥发酚含量的测定结果,对FIA法检测挥发酚过程中的不确定度来源进行了分析,得出测量结果的扩展不确定度,结果表明除去标准溶液,样品重复性测定引入的不确定度最大;当水中挥发酚含量为9.1 ug/L时,其扩展不确定度为0.3 ug/L(k=2)。 相似文献
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通常水中二氧化碳含量测定采用酸碱滴定法,但尿液中高含量的氨严重干扰测定,通过加热预处理除去试样中的氨后,就可以采用酸碱滴定法测定尿液中的二氧化碳含量.文章讨论样品预处理过程中各种因素的影响,二氧化碳标样的测定结果与标准值的吻合情况及多个尿液样品多次平行测定情况(分析结果的RS为0.43%~3.65%).采用不同浓度的盐酸标准溶液,可用于尿素装置二氧化碳含量为0.01%~40%的各尿液中二氧化碳含量的测定. 相似文献
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Fred W. Billmeyer 《Color research and application》1994,19(6):413-425
Some aspects of the metrology of fluorescence are reviewed. ASTM Committee E-12 on Appearance has written two documentary standards on the instrumental measurement of fluorescent colors. Test Method E 1247 provides two procedures for detecting small amounts of fluorescence that might affect the measurement or use of nominally nonfluorescent materials. Practice E 991 deals with the measurement of specimens meant to be viewed under standard natural daylight, and that, therefore, must be illuminated by a good instrument daylight simulator. Two procedures are given for assessing the suitability of the simulator, and the required instrument geometry is specified. A future ASTM standard is under consideration that would describe methods for correcting the data obtained with another instrument source to the data that would have been obtained with standard daylight illumination. Two groups of standard specifications exist for fluorescent colors used for signaling or safety enhancement. One defines suitable chromaticities for both red and orange colors [among others], but ignores the fact that these colors cannot always be obtained with good lightfastness by use of existing pigments. the other group provides instead a red-orange specification for which specimens with good lightfastness can be obtained. the relative merits of the two groups are discussed. 相似文献
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Smith J. W. Ferguson G. N. Mills J. D. 《Journal of the American Oil Chemists' Society》1974,51(3):61-64
An electronic image scanning measurement method was developed to obtain objective measurements of the area of resistant dark
contaminants, broadly referred to as dirts, contained in cottonseed linters and hull fibers. The method is based upon the
use of the AOCS standard cellulose yield residue. The yield residue (20 g) was bleached and formed into a 10 × 12 in. test
sheet, and the projected area of visible dirts in 42 fields on each side of the sheet was meausred. Areas as small as 0.1
mm2 in a field 30 × 41 mm can be measured. The results were converted to area, summed, and compared with the visual measurements
obtained using the method of Jurbergs and Dowling. Statistical analysis gave standard deviations of ca. 8% and 25%, respectively,
for new and the earlier procedures. The instrument standard deviation was shown to be ca. 1% relative. A comparison of the
two methods using samples of 1099 different lots of linters gave a 0.94 correlation coefficient.
Presented at the AOCS Spring Meeting, New Orleans, April 1973. 相似文献
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概率单位平行线法在乙肝疫苗效力试验数据统计中的应用 总被引:1,自引:1,他引:1
采用概率单位平行线法对7个厂家7年间生产的血源乙型肝炎疫苗的效力试验结果进行统计分析,并与现行规程的Reed-Muench法计算结果比较,前法可进行线性、平行性检验及可信限率等分析,有效地区分试验误差,准确客观地评价疫苗效力。用此法时,剂量应不少于4组;各剂量反应率应落在经验区间内;EDS50可信限率应≤60%,相对效价可信限率应≤150%;可用合格、不合格或复试三个标准予以评价。本文对疫苗效力的稳定性及试验的一致性进行了质量分析,计得共同回归系数为1.5896、总体相对效价为2.31(2.20,2.42)。上述方法已用BASIC语言编制了程序,可用于常规检定。 相似文献
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The overall performance of a firefighter turnout suit can only be evaluated using both bench‐scale tests and an assessment based on an instrumented manikin under defined, close to real‐life conditions in a laboratory. Using manikins in rating protective clothing has already a long history which will be reflected in this paper. Efforts all over the world to reproduce a flame engulfment situation in a laboratory are currently being combined in a new draft international standard (ISO/DIS 13506.3). A round robin test showed an acceptable reproducibility for this method based on a manikin test and a gas burner system. An overview of existing measurement systems and the results of this round robin are discussed and possible improvements for the standard flame engulfment test method are proposed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Summary 1. The measurement of the foaming properties of soaps and detergents is shown to be possible by comparing the relative stability
of a foam by measuring the effect of an arbitrary standard destructive mechanism acting upon a volume of foam during production
under standard conditions and protected from adventitious destructive forces.
2. A simple apparatus and procedure for carrying out foam tests has been described and the reproductibility of the test evaluated.
3. Previous studies of foam comparison have been reviewed and criticisms offered regarding the procedures and conceptions
involved. 相似文献
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以2017年8月—2020年12月在中国化工学会培训中心接受专业技术培训的792名学员作为观察对象,通过与传统教学法比较来评价循证教学法在专业技术人员职业继续教育中的效果。研究期间,开设7期新材料领域的专题培训班,每期培训班举办2场,分别作为对照组和实验组,实验组采用循证教学法,对照组采用传统教学法。培训结束以后,通过统一考试形式对比2组学员对专业知识和技能的掌握情况,实验组学员的考试成绩明显优于对照组学员。结果表明:相比于传统教学法,将循证教学法应用于职业继续教育可取得更好的效果,可以更好地帮助学员提高专业技术能力。 相似文献
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对用毛细管电泳法测定PTA中4-CBA和p-TOL的不确定度进行了评定,结果说明,增加样品重复测定次数,增加标准曲线校正点,可以达到减少不确定度的目的。 相似文献