Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Assessing the Data

The sensitivity of an analytical method can be defined as the slope of the calibration curve, that is, as the ratio of change in the instrument response with a change in the analyte concentration. Other definitions are also used. In AAS, sensitivity is defined as the concentration of analyte that produces an absorbance of 0.0044 (an absorption of 1%), for example. When the term sensitivity is used, it should be defined. [Pg.55]

A good analytical method should be both precise and accurate that is, it should be reliable or robust. A robust analytical method is one that gives precise and accurate results even if [Pg.57]


Risk characterization is tlie process of estimating tlie incidence of a healtli effect under tlie various conditions of human or animal exposure as described in the exposure assessment. It evolves from both dose exposure assessment and toxicity response assessment. The data are then combined to obtain qualitative and quantitative expression of risk. [Pg.419]

Impact Assessment. One of the more common methods of assessing the data is to put a numerical value on various potential environmental impact criteria namely ... [Pg.42]

This monitoring framework should be apphed across broad geographic regions. This book recommends a national or (preferably) continental scale of assessment. The data collected in the United States shonld also be comparable, to the extent feasible and appropriate, with other North American and global mercury monitoring efforts, particularly monitoring of atmospheric transport and deposition. [Pg.199]

Van Oers et al. [4] conducted a review of over 30 LCI databases to assess the data... [Pg.10]

In this chapter the risk assessment is briefly introduced. Risk assessment is divided into four steps hazard identification, hazard characterization, exposure assessment, and risk characterization. This chapter also highlights five risk and life cycle impact assessment models (EUSES, USEtox, GLOBOX, SADA, and MAFRAM) that allows for assessment of risks to human health and the environment. In addition other 12 models were appointed. Finally, in the last section of this chapter, there is a compilation of useful data sources for risk assessment. The data source selection is essential to obtain high quality data. This source selection is divided into two parts. First, six frequently used databases for physicochemical... [Pg.91]

Fuzzy logic is often referred to as a way of "reasoning with uncertainty." It provides a well-defined mechanism to deal with uncertain and incompletely defined data, so that one can make precise deductions from imprecise data. The incorporation of fuzzy ideas into expert systems allows the development of software that can reason in roughly the same way that people think when confronted with information that is ragged around the edges. Fuzzy logic is also convenient in that it can operate on not just imprecise data, but inaccurate data, or data about which we have doubts. It does not require that some underlying mathematical model be constructed before we start to assess the data. [Pg.239]

Another simple method that has been used for assessing the data for many families of compounds, say ML , consists in plotting AH (ML ) versus A//y°(LH), with ML and LH in either their standard reference states (their stable physical states at 298.15 K and 1 bar) or in the gas phase20. It has been observed that many21 of the above plots which involve reliable thermochemical data define excellent straight lines. This empirical linear relationship may be expressed as equation 2. [Pg.249]

The thermal decomposition of dimethyl mercury in the presence of radical scavengers has been thoroughly investigated61-65. The basic mechanism, the preexponential factor and the activation energy are all well established. There is still considerable doubt about the mechanism of the pyrolysis in the absence of chemically active additives. Consequently, the quantitative interpretation of rate data from such systems is of doubtful value. Systems using effective scavengers will be discussed first. The quantitative results from these systems will be used in assessing the data obtained in the absence of additives. [Pg.217]

Frequently, the existence and source of such information is nnknown thns the data are not examined. Even when the existence and sonrces of information are known, decisions must be made in order to make an informed, and often quick decision on the next steps, even if later, one decides not to nse it for a particular application. Knowing about the relevant data gives investigators and analysts the ability to assess the data based on qnality assnrance criteria. This is especially true for users near the end of long decision processes, such as site cleanup, ecological risk assessments, and natural resource damage assessments. [Pg.3]

Pohjala, L, Tammela, P., Samanta, S.K, Yli-Kauhaluoma, J. and Vuorela, P. (2007) Assessing the data quality in predictive toxicology using a panel of cell lines and cytotoxicity assays. Analytical Biochemistry, 362, 221-228. [Pg.342]

The interpretation of the intensities of lines observed in astrophysical sources requires a wide variety of reliable atomic and, to a lesser extent, molecular data [1]. Also, the steady development of high temperature plasmas, in relation to the fusion programmes ongoing in several countries, has given rise to a considerable interest in the spectroscopy ofheavy and/or highly ionised atoms [2], The spectacular advance of some experimental techniques has not diminished the need for reliable theoretical data. In the production of spectroscopic quantities such as oscillator strengths to fulfill the present demands of both the astrophysics and plasma physics communities, several authors [3-5] have emphasised the need for both experimentalists and theoreticians to self-assess the data they supply. [Pg.49]

Identify the types of QA/QC samples during the planning phase specify what kind of data will be obtained from their analyses and how they will be used for assessing the data quality and usability. [Pg.76]

Preparation and analytical batches must be clearly identified with a unique number in laboratory bench sheets, notebooks, and computer systems. The same applies to QC check samples associated with each batch. During data quality assessment, the data user will determine the quality of the field sample data based in the results of the batch QC check samples that are part of the preparation and analytical batches. The data user will examine batch QC check samples first and, if they are acceptable, will proceed to individual sample QC checks. A complete examination of these QC checks will enable the data user to evaluate the quantitative DQIs (accuracy and precision). A combination of acceptable batch QC checks and individual QC checks makes the data valid on condition that the qualitative DQIs (representativeness and comparability) are also acceptable. [Pg.255]

By the time Step 5 is conducted, accuracy, precision, and representativeness have been assessed and the data have been qualified accordingly. In DQA Step 5, the chemist will assess the data collected for each intended use in terms of the other remaining PARCC parameters, comparability and completeness. [Pg.289]

Examples of product class carcinogenicity hazard identifications and assessments and ultimate risk communications for biopharmaceuticals approved in the United States for chronic use or based on potential cause for concern are provided in Table 19.4a (products without carcinogenicity assessment) and Table 19.4b (products with carcinogenicity assessment). The data are derived from publicly available regulatory assessments and product labels. Specific examples are discussed below. [Pg.426]

In this paragraph, we discuss aspects of mixture experiments that need attention while analyzing and assessing the data. These aspects may be endpoint, test organism, or chemical specific ... [Pg.154]

The experience gained from assessing the data-rich chemicals lithium and boric acid using the evaluative process described by J.A. [Pg.98]

Sorensen, B. (1987). Chernobyl accident assessing the data. Nuclear Safety 28, 443-447. [Pg.433]

Transition state theory has been particularly useful in providing a framework for assessing the data on metathetical reactions. According to this theory the rate constant can be expressed as... [Pg.265]

Knowledge of trends of thermochemical data found for other elements may help to show that, in fact, the values for the trialkyl species in Table 1 are unreasonable. A method that seems to be a generally valid approach is to assess the data for families of compounds, say ML , by plotting AH/(ML ) versus Af//(LH), either with ML and LH in their standard reference states (i.e. in their stable physical states at 298.15 K... [Pg.157]

The original manufacturing formula (HV) and five variations are performed in the first step of the synthesis. Six samples are analysed. The results of these six analyses are used to assess the validation of this process step. In this case validation of the analytical method is a prerequisite for any decision that is made about the validity of the process. This information is needed before the process research chemist can start variations of the process otherwise it is possible that the data received cannot be assessed. The difficulty of assessing the data of the process validation results from the fact that the data is influenced by the analytical method and the uncertainty of the chemical process. If the uncertainty of the analytical method is larger or in the same range as the variations of the chemical process, assessment of the data is not possible. [Pg.77]

As an example of the typical numbers involved, Matchett and Baker [J. Sep. Proc. Technol., 9 5 (1988)] used their correlations to assess the data of Saeman and Mitchell for an industrial rotary dryer with D = 1.83 m and L = 10.67 m, with a slope of 4°, 0.067 m/m. For a typical run with UG = 0.98 m/s and N = 0.08 r/s, they calculated that UPl = 0.140 m/s, VPy= — 0.023 m/s, UPl = 0.117 m/s, and Up2 = —0.02 m/s. The dryer modeled was countercurrent and therefore had a greater slope and lower gas velocity than those of a cocurrent unit for the latter, UPl would be lower and UPl positive and larger. The ratio Ts/tg is approximately 12 in this case, so that the distance traveled in dense-phase motion would be about twice that in the airborne phase. [Pg.75]

By combining assays from the nine providers in Appendix 1.1, inhibitor binding for up to 407 wild type protein or lipid kinases can be assessed. The data in Appendix 1.1 shows that the kinase families can be well covered by a combination of the commercial assay panels. Where one panel may be deficient, other panels provide coverage. [Pg.12]

The nurse should check the client s renal status, but the priority nursing intervention is assessing the data for which the client is receiving the medication. [Pg.347]


See other pages where Assessing the Data is mentioned: [Pg.201]    [Pg.38]    [Pg.119]    [Pg.93]    [Pg.8]    [Pg.224]    [Pg.676]    [Pg.207]    [Pg.556]    [Pg.1396]    [Pg.289]    [Pg.268]    [Pg.45]    [Pg.24]    [Pg.150]    [Pg.1395]    [Pg.334]    [Pg.208]    [Pg.66]    [Pg.4]    [Pg.57]    [Pg.279]   


SEARCH



Data assessment

The Data

© 2024 chempedia.info