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1.
针对蔬菜中噻嗪酮残留的检测,采用高效液相色谱分析,研究了该方法的不确定度来源和结果的扩展不确定度。结果表明,农残提取、检测、外标曲线和分析仪器对噻嗪酮残留结果产生的相对不确定度分量分别为0.000 6、0.005 9、0.002 1和0.011 9,合成标准不确定度为0.013 5,噻嗪酮农残的扩展不确定度为0.013μg·g-1(k=2),噻嗪酮残留量可以表示为(0.487±0.013)μg·g-1。4个不确定度分量中分析仪器对结果的影响最大,样品检测的影响其次。高效液相色谱法检测蔬菜中噻嗪酮残留量的结果可靠。  相似文献   

2.
采用紫外分光光度法测定海水中石油类浓度,并对测量结果的不确定度进行了评定。分析了实验过程中不确定度的各项来源,包括标准溶液制备、仪器重复测量、标准曲线回归、前处理方法等,同时研究了各不确定度分量的计算方法,最后合成得样品的标准不确定度。当海水中石油类含量为0.081 8 mg/L时,扩展不确定度为0.011 6 mg/L(k=2)。实验结果表明,标准曲线非线性引入的不确定度对测量结果的影响最大。  相似文献   

3.
为探讨滤棒含水率测量不确定度评定方法,选用GUM法讨论不确定的主要来源,计算各个不确定度分量、合成不确定度和扩展不确定度。结果表明:在烘箱法检测滤棒含水率过程中,由样品干燥仪器烘箱引入的不确定度最大,由重复性、测量仪器天平引入的不确定度较小。包含因子k=2的扩展不确定度为0.16%。  相似文献   

4.
胡俊庆  张健华 《科技信息》2012,(36):I0191-I0192
本文分析了用碱性过硫酸钾消解紫外分光光度法测试水质总氮过程中不确定度产生的来源,对各不确定度分量进行评定及合成,并计算得出合成不确定度和扩展不确定度。本次水质总氮测量结果为:2.13±0.08mg/L,k=2。  相似文献   

5.
采用《测量不确定度评定与表示为指南》,以火焰原子吸收法测定岩矿样品中的金为例,对测量结果进行不确定度评定。测量结果的不确定度由标准溶液、称样量、标准物质测量以及仪器重复测量等所引入的不确定度分量组成,在对各个不确定度分量进行量化的基础上,最后合成得到测量结果的标准不确定度,通过乘以95%置信概率下的扩展因子2,获得测量结果的扩展不确定度。  相似文献   

6.
采用电感耦合等离子体发射光谱法(ICP-AES)测定水中硫酸根含量,依据不确定度评定的方法,分析了不确定度来源,量化不确定度分量,计算检测结果的合成标准不确定度和扩展不确定度。饮用水样品中硫酸根平均值为35.85 mg/L(n=6),扩展不确定度为0.56 mg/L。结果表明ICP-AES测定水中硫酸根的不确定度主要来源于标准溶液的配制、标准曲线拟合及实验过程的重复性测定。  相似文献   

7.
分析和讨论了原子吸收光谱法测定水质中铁含量的不确定度来源,并对各种不确定度分量进行了量化与合成,不确定度主要来源于标准溶液配制产生的不确定度分量,其次是分析仪器和样品重复性测量产生的不确定度分量,计算出水质中的铁含量测量结果的合成不确定度为0.004,当水质样品中铁含量为0.0389mg/L时,合成不确定度为1.56×10~(-4)mg/L,扩展不确定度为3.12×10~(-4)mg/L(置信水平为95%,k=2)。  相似文献   

8.
对高效液相色谱测定连翘叶茶中连翘苷的方法进行不确定度评定。建立HPLC测定连翘叶茶中连翘苷的分析方法,参考相关规定,建立数学模型,考察测量过程中影响不确定度的因素,包括样品不均匀性、量器体积、对照品纯度、对照品称量和仪器本身等内容,计算合成不确定度和扩展不确定度。结果表明,该方法的不确定度主要由样品不均匀性和仪器本身引入,合成相对标准不确定度为0.010 9。  相似文献   

9.
水中阴离子最常用的分析方法是离子色谱法。对离子色谱法测定水中硫酸根离子的不确定度进行了评定。分析了峰面积(y)、斜率(b)和截距(a)等主要影响因素带来的不确定度。计算了不确定度分量及合成不确定度,扩展不确定度为0.28 mg·L-1.  相似文献   

10.
按照国家标准GB 5009.149-2016《食品安全国家标准食品中栀子黄的测定》的检测原理和方法,采用高效液相色谱法测定蛋糕中的栀子黄,标准规定了食品中栀子黄的代表性成份为藏花素和藏花酸。根据CNAS-GL06《化学分析中不确定度的评估指南》和JJF 1059.1-2012《测量不确定度评定与表示》的规定,建立数学模型,分析高效液相色谱法测定蛋糕中的藏花素和藏花酸含量的不确定度来源,并对各个不确定度分量进行量化,计算合成标准不确定度和扩展不确定度:糕点中藏花素测定结果为(0.060±0.006)g/kg,k=2,p=95%;藏花酸的测定结果为(0.026±0.002)g/kg,k=2,p=95%。评定结果发现在评估的6个不确定度分量中,影响检测结果不确定度的主要分量为标准溶液配制引入的不确定度、标准校正曲线拟合引入的不确定度。实验中可通过减小这些不确定度分量来提高检测结果的可靠性。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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