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1.
对通过统计质量保证(SQA)技术进行分析测试实验室内部质量控制(IQC)的方法作了初探。研究结果表明,SQA技术的应用能保证实验室始终处于统计受控状态,确保测试数据的有效性,有利于分析测试实验室质量保证活动的开展。  相似文献   

2.
基于实验室长期积累的质控数据评估测量不确定度的top-down方法具有广泛应用前景,质控图法和稳健统计法是其中常见方法。质控图法要求测量数据中不含离群值,对测量数据时间顺序有明确要求。稳健统计法是指不用识别、剔除离群值,直接应用全部测量数据,将离群值对统计分析结果影响降低到最小的统计分析方法。本文基于质控图法、稳健统计和实验室长期积累的质控数据对固体样品汞含量热裂解-原子吸收分析方法的测量不确定度进行了评估,对两种方法计算结果、实验室评估的测量不确定度和标准样品标称值的不确定度进行了比较。计算结果表明,两种方法结果基本吻合,基于实验室质控数据期间精密度评估的不确定度明显小于标准样品标称值,结果合理。  相似文献   

3.
评定柱后衍生–液相色谱法测定蔬菜中克百威残留量的不确定度。根据JJF 1059.1—2012 《测量不确定度评定与表示》和JJF 1135—2005 《化学分析测量不确定度评定》中有关规定,对该方法建立不确定度评估结果计算的数学模型,对测定中的不确定度来源进行分析和评估。测量不确定度的主要来源包括标准溶液稀释过程、样品的称量、样品溶液的稀释定容、重复性测量,分别对不确定度分量进行计算,并合成相对标准不确定度。当蔬菜中克百威和3-羟基克百威残留量为0.020 mg/kg时,扩展不确定度分别为0.001 3、0.001 6 mg/kg(k=2),克百威和3-羟基克百威残留量分别表示为(0.020±0.001 3)、(0.020±0.001 6) mg/kg(k=2)。该方法确定了不确定度主要来源为标准溶液的稀释过程,为检验结果的准确性及可靠性提供了技术依据。  相似文献   

4.
基于实验室长期积累的质控数据评估测量不确定度的top-down方法具有广泛应用前景,质控图法和稳健统计法是其中常见方法。质控图法要求测量数据中不含离群值,对测量数据时间顺序有明确要求。稳健统计法是指不用识别、剔除离群值,直接应用全部测量数据,将离群值对统计分析结果影响降低到最小的统计分析方法。基于质控图法、稳健统计和实验室长期积累的质控数据对固体样品汞含量热裂解-原子吸收光谱分析方法的测量不确定度进行了评估,对两种方法计算结果、实验室评估的测量不确定度和标准样品标称值的不确定度进行了比较。计算结果表明,两种方法结果基本吻合,基于实验室质控数据期间精密度评估的不确定度明显小于标准样品标称值,结果合理。  相似文献   

5.
建立用于Top-Down法不确定度评定的Excel电子表格,可评定期间精密度不确定度分量、偏倚不确定度分量,并计算合成扩展不确定度.该电子表格还可用于对测量系统进行正态性、独立性和一致性检验,而不需借助其它的专业统计分析软件.通过该电子表格获得的不确定度数据和测量系统性能检验统计量与RB/T 141-2018中的实例一...  相似文献   

6.
《分析试验室》2021,40(9):1039-1043
采用QuEChERS-液相色谱/串联质谱方法测定青椒中噻虫嗪的残留量,并对其测量的结果进行不确定度的评估。结合检测流程建立不确定度的数学模型,分析了影响不确定度评估的主要因素,并通过公式计算其合成不确定度和扩展不确定度。通过评估发现,不确定度主要的影响因素是标准溶液的配制、检测仪器的稳定性和试验前处理过程。当青椒中噻虫嗪的残留量测定结果为140μg/kg时,其扩展不确定度为8μg/kg,结果表示为(140±8)μg/kg,k=2。该方法可为科学评价QuEChERS-液相色谱/串联质谱测定农残的测量结果的准确性提供参考。  相似文献   

7.
采用封闭酸溶电感耦合等离子体质谱(ICP-MS)法测定岩石样品,分别对47种元素的测量结果不确定度进行评定。通过分析测试方法和测量条件,得到测量结果的不确定度主要由样品称量、样品溶液定容和样品溶液中元素浓度测量引入。在实验室质控条件下,对各不确定度分量进行评定和计算,其中随机因素导致的不确定度采用期间精密度试验综合评价,即采用A类方法评定。共完成了16个岩石国家标准物质(GBW 07103~GBW 07123)47种元素测量结果的不确定度合成,并参照GB/T 6379.2-2004,建立了含量w与扩展不确定度U之间的关系模型,运用这一关系模型可得到测量结果的不确定度估计值,只要测量过程本身或所使用的设备未变化,就不需要再重复进行不确定度评估。  相似文献   

8.
采用固相萃取-高效液相色谱法测定水中呋喃丹浓度,对测量结果的不确定度进行了评定。根据《测量不确定度评定与表示(》JJF 1059-1999)中有关规定,建立呋喃丹不确定度分析数学模型。结果表明,该方法测量结果不确定度的主要来源为标准溶液的配制、定容和重复性测试,当水样中呋喃丹的浓度为0.03 mg/L时,扩展不确定度为0.0044 mg/L(k=2)。  相似文献   

9.
对氢化物发生-原子荧光法测定土壤中砷的不确定度进行了分析,找出影响不确定度的因素,对不确定度进行评估,给出不确定度,能如实反映测量的置信度和准确度。  相似文献   

10.
宋增锋  马辰 《分析试验室》2007,26(Z1):294-297
对紫外分光光度法测定总蒽醌含量的测量不确定度进行分析,以期找出影响不确定度的因素,为评价检测报告提供科学依据.用分光光度法测定虎杖中总蒽醌的含量,并根据<测量不确定度评定与表示>(JJF1059-1999)中有关规定评估其不确定度.本次实验的不确定度评估为0.0912%.  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.
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   

13.

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   

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.
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   

16.
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   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

19.
20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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