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1.
A procedure for estimation of measurement uncertainty of photometric analysis based on the ISO GUM method is presented. Two variations of the procedure—for the calibration graph and the standard addition method, respectively—are discussed. The variations are based on mathematical models involving 64 and 80 input quantities, respectively. The uncertainty of the result strongly depends on changes in experimental details. These dependencies are explored for a practical example of determination of the iron content of aluminum. The importance of taking uncertainty from sample preparation into account in uncertainty estimation is stressed. The number of effective degrees of freedom is calculated and discussed. The examples are available as GUM Workbench files in the Electronic Supplementary Material.Electronic Supplementary Material Supplementary material is available for this article at .
相似文献
Ivo LeitoEmail: Phone: +372-7-375259Fax: +372-7-375264 |
2.
Cox Maurice G. Desenfant Michèle Harris Peter M. Siebert Bernd R. L. 《Accreditation and quality assurance》2003,8(12):548-554
Basic concepts and implementations of the model-based approach to uncertainty evaluation are discussed. One implementation is that of the law of propagation of uncertainty with the use of the central limit theorem as recommended in the Guide to the expression of uncertainty in measurement (GUM). Another is the propagation of distributions, the subject of a supplemental guide to the GUM, which is at an advanced stage of development. It falls in the category of other analytical and numerical methods indicated in the GUM. Two testing applications are used to illustrate the principles: tennis-ball rebound and tensile strength.
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Maurice G. CoxEmail: Phone: +44-20-8943-6096Fax: +44-20-8977-7091 |
3.
Pavel A. Zagrebin Galina A. Tsirlina Renat R. Nazmutdinov Oleg A. Petrii Michael Probst 《Journal of Solid State Electrochemistry》2006,10(3):157-167
The advantages of corrected Marcus plots as compared to the more traditional corrected Tafel plots are discussed and illustrated
by the treatment of experimental data. The procedures are proposed to avoid the uncertainties of EDL correction and to estimate
the reliable values of transmission coefficient and total reorganization energy. Special emphasis is placed on the diagnostics
of activationless reactions in frames of the same method.
Dedicated to Professor M.A. Vorotyntsev on the occasion of his 60th birhtday.
相似文献
Galina A. TsirlinaEmail: |
4.
5.
The estimation of electrochemical quartz crystal microbalance (EQCM) frequencies from a given cyclic voltammetric data is analysed using underpotential deposition (UPD) of metals as an illustrative process. The crucial role played by the surface roughness of electrodes and electrosorption valency of the depositing species is pointed out. The computed EQCM frequency shifts for the UPD of Cd and Tl on polycrystalline Ag electrodes are in satisfactory agreement with the experimental data.
相似文献
M. V. SangaranarayananEmail: |
6.
Michael Thompson 《Accreditation and quality assurance》2008,13(8):479-482
The currently recommended design of collaborative trials (interlaboratory method performance studies) is examined in relation
to the usefulness of the resulting statistics. It is suggested that larger experiments, without duplicate analysis, would
be more informative.
相似文献
Michael ThompsonEmail: |
7.
Antonio Menditto Marina Patriarca Bertil Magnusson 《Accreditation and quality assurance》2007,12(1):45-47
Clear definitions of basic terms, used to describe the quality of measurements, is essential for communication among scientists
as well as when reporting measurement results to clients. Even if appropriate definitions are given in international standards
and guidelines, the understanding of some basic terms sometimes proves difficult. The reasons for this are various, e.g.,
the same words being defined rather differently in encyclopaedias and in international standards as well as concepts, well
established in some languages, that may be relatively new in other national communities and at large in the international
one. Here we present a matrix intended to clarify the relationships between the type of error affecting an analytical measurement,
the respective qualitative concepts (performance characteristics) and their quantitative expression.
相似文献
Antonio MendittoEmail: |
8.
Hinne Hettema 《Foundations of Chemistry》2008,10(2):135-142
Michael Weisberg’s recent 2007 paper on the chemical bond makes the claim that the chemical notion of the covalent bond is
in trouble. This note casts doubts on that claim.
相似文献
Hinne HettemaEmail: |
9.
Guy Yardeni Israel Zilbermann Eric Maimon Haim Cohen Dan Meyerstein 《Research on Chemical Intermediates》2009,35(4):543-554
A new CeIII complex was synthesized by mixing the ligand “dioxocyclam” with CeIII ions at pH 8.0 and its redox properties were investigated.
相似文献
Dan Meyerstein (Corresponding author)Email: |
10.
Yan Gao Sabrina Reischmann Johannes Huber Tobias Hanke Rudolf Bratschitsch Alfred Leitenstorfer Stefan Mecking 《Colloid and polymer science》2008,286(11):1329-1334
Single semiconductor quantum dots were embedded into polymer particles with diameters below 0.1 μm by an emulsion polymerization
procedure or via a secondary dispersion approach. The photoluminescence properties of the nanocrystals are retained upon encapsulation,
as demonstrated by fluorescence confocal microscopy.
相似文献
Stefan MeckingEmail: |
11.
Vaporization enthalpies for the isomeric diazines were discussed within the context of recent measurements and estimation
techniques. It is suggested that pyridazine shows enigmatic behavior.
相似文献
Joel F. Liebman (Corresponding author)Email: |
12.
Saad Alshehri John Burgess Colin D. Hubbard Christopher J. Jones Amit K. Das 《Transition Metal Chemistry》2008,33(4):417-420
The kinetics of substitution by alcohols and by aniline at [tris(3,5-dimethylpyrazolyl)hydroborato]molybdenum nitrosyl dihalides in toluene solution at 298.2 K and at atmospheric pressure
are reported and interpreted in terms of an associative mechanism.
相似文献
Colin D. HubbardEmail: |
13.
René Dybkaer 《Accreditation and quality assurance》2007,12(12):661-663
Terminology within a small laboratory community can be informal without danger of misunderstanding, but communication with
a wider audience and not least in publications, needs unequivocal terms for defined concepts. As an example, the many meanings
of “concentration” are explored to present a systematic nomenclature, including a concept diagram.
相似文献
René Dybkaer |
14.
Niki Baccile Anna Fischer Beatriz Julián-López David Grosso Clément Sanchez 《Journal of Sol-Gel Science and Technology》2008,47(2):119-123
Core-shell and homogeneous distributions of functionalized cerium oxide nanoparticles within spray-dried mesostructured silica
spheres are achieved by modification of synthesis parameters such as the templating agent and nanoparticle capping functions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Clément Sanchez (Corresponding author)Email: |
15.
Michael Noyong Buelent Ceyhan Christof M. Niemeyer Ulrich Simon 《Colloid and polymer science》2006,284(11):1265-1273
The formation and the optical features of two-dimensional aggregates formed by DNA-directed immobilization and cross-linking of bifunctional DNA–gold nanoparticles at flat gold substrates are analyzed. The samples are structurally characterized by atomic force microscopy to evaluate the particle size, the particle densities, and the degree of aggregation. The optical characteristics determined by UV/visible measurements are correlated with the structural features observed.
相似文献
Ulrich SimonEmail: |
16.
Protein microarrays for diagnostic assays 总被引:1,自引:1,他引:0
Hartmann M Roeraade J Stoll D Templin MF Joos TO 《Analytical and bioanalytical chemistry》2009,393(5):1407-1416
Protein microarray technology has enormous potential for in vitro diagnostics (IVD). Miniaturized parallelized immunoassays
are perfectly suited to generating a maximum of diagnostically relevant information from minute amounts of sample whilst only
requiring small amounts of reagent. Protein microarrays have become well-established research tools in basic and applied research
and the first products are already on the market. This article reviews the current state of protein microarrays and discusses
developments and future demands relating to protein arrays in their role as multiplexed immunoassays in the field of diagnostics.
相似文献
Thomas O. JoosEmail: |
17.
Stephen L. R. Ellison 《Accreditation and quality assurance》2005,10(7):338-343
A spreadsheet method allowing rapid calculation of combined standard uncertainties is described. The model used allows explicitly
for correlation effects, and requires a user to enter only the parameters, the calculation used to obtain the final result
(including relevant influence factors), the individual standard uncertainties for the parameters, and estimates of correlation
coefficients where necessary. The estimation of correlation coefficients in common cases is discussed, and it is shown that
correlation is likely to be practically significant only when the correlated contribution to individual standard uncertainties
is significantly over about 30% of the relevant standard uncertainty, leading to correlation coefficients |r| greater than 0.1. The implementation includes a more robust differentiation algorithm than previously reported for spreadsheet
use, and initial preparation of the spreadsheets has been automated. The principle is illustrated with a simple example.
Electronic Supplementary Material Supplementary material is available in the online version of this article at and is accessible for authorized users.
相似文献
Stephen L. R. EllisonEmail: |
18.
Klaus Ruthenberg 《Foundations of Chemistry》2009,11(2):79-91
Immanuel Kant has built up a dualistic epistemology that seems to fit to the peculiarities of chemistry quite well. Friedrich
Paneth used Kant’s concept and characterised simple and basic substances which refer to the empirical and to the transcendental
world, respectively. This paper takes account of the Kantian influences in Paneth’s philosophy of chemistry, and discusses
pertinent topics, like observables, atomism and realism.
相似文献
Klaus RuthenbergEmail: |
19.
Albert Koulman Geoffrey A. Lane Scott J. Harrison Dietrich A. Volmer 《Analytical and bioanalytical chemistry》2009,394(3):663-670
The current developments in metabolomics and metabolic profiling technologies have led to the discovery of several new metabolic
biomarkers. Finding metabolites present in significantly different levels between sample sets, however, does not necessarily
make these metabolites useful biomarkers. The route to valid and applicable biomarkers (biomarker qualification) is long and
demands a significant amount of work. In this overview, we critically discuss the current state-of-the-art of metabolic biomarker
discovery, with highlights and shortcomings, and suggest a pathway to clinical usefulness.
相似文献
Dietrich A. VolmerEmail: |
20.
Electrochemical studies of bi- and polymetallic complexes featuring acetylide based bridging ligands
Paul J. Low Rachel L. Roberts Richard L. Cordiner František Hartl 《Journal of Solid State Electrochemistry》2005,9(11):717-731
Acetylide-based bridging ligands have been widely used in the preparation of complexes that display a degree of electronic
interaction between metal-based redox groups located at the ligand termini. The electrochemical response of these systems
has been selectively reviewed, with a focus on the variation in properties that accompany changes in the structure of the
bridging ligand and the nature of the metal groups.
相似文献
Paul J. LowEmail: |