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Quantitative analysis definition

Therefore the basic task of scientific work is development of sensitive, selective and simple methods of quantitative definition of the total contents of the alkaloids in the expert-criminal objects with the help of electrochemical methods of the analysis. [Pg.383]

Although concepts of invariant spatiotemporal measurement are implicitly assumed to exist in this model universe, we make no apriori assumptions about their quantitative definition, but require that such definitions arise naturally from the stmcture of the model universe and from the following analysis. [Pg.318]

Zartarian VG, Ott WR, Duan N (1997) A quantitative definition of exposure and related concepts. Journal of Exposure Analysis and Environmental Epidemiology, 7(4) 411-437. [Pg.95]

The alkaloid contents in a single alkaloid cell from M. cordata roots of three different thicknesses (age 1-2 years) were determined as follows. The liquid from various numbers of alkaloid cells (Table II) was removed uniformly and collected in the microtrap. The liquid in the capillary and connection tubes was washed into the microtrap to make a certain definite volume for analysis. Quantitative analysis of each alkaloid was carried by preparing a calibration graph (4). Figure 3 shows the HPLC chromatogram of alkaloids from the alkaloid cells. The content of each alkaloid per single alkaloid cell in tissues from three different thickness of roots and its ratio are shown in Table II. The liquid in colorless cells contained only a minute amount of protopine and allocryptopine (Fig. 3). The thicker the roots, the more alkaloids were contained in a single alkaloid cell. In any thickness of root, the content of protopine-type alkaloids exceeded that of benzo[c]phenanthridine-type alkaloids. The ratio of the former to the latter was almost steady over 5 mm of root thickness (86-87%). The ratio of alkaloids in methanol extracts of the same fresh samples (thickness 5 mm) was determined by HPLC (Table III). The ratio of protopine-type alkaloids in the methanol extracts ( 80%) was less than that in the liquid from the alkaloid cells ( 87%). This was because the liquid in alkaloid cells near the cambium were picked up more than that in center cells (pith). Thus, intracellular components scattered in different places are analyzed qualitatively and quantitatively in situ by HC. [Pg.183]

Kaplan S and Garrick BJ (1981) On the quantitative definition of risk. Risk Analysis 1 11-27. [Pg.2311]

From the point of view of structural analysis of nitrogen containing polymers, simultaneous application of both 13C and 15N NMR techniques will result in a more complete qualitative and quantitative definition of the polymer system, because the two nuclei/spectroscopies behave complementarily. [Pg.195]

LC-MS methods have proved very satisfactory as alternatives to the LC-FL method for precise analysis ofYTXs. There are advantages in the simple sample preparation and wider range of analogues detected. However, the greater instrument costs can only be justified if LC-MS is used for quantitative multitoxin analysis where definitive results are obtained for YTXs and a range of other toxin classes in a single run without the need for further confirmatory analyses. Several such methods have been developed and validated. " ... [Pg.31]

All of the above illustrations are outside the realm of analytical chemistry and instrumental analysis, which are vital for qualitative and quantitative definition or description of scenarios in environment, agriculture, civil engineering, medicine, and similar fields of scientific and technological endeavor. Since chemical data derived by analytical methods are critical for decision-making in these fields, many examples of the applications of MCDM can be found in such fields. One important common element in decision-making in these fields is that it is becoming more and more multidisciplinary, i.e., several disparate stakeholders, such as administrators, scientists. [Pg.605]

A system is a part of the universe within a certain domain in space and time. What is an environment Outside the frontier of the system is the environment [1], Here, system shall have an identity, that is, deterministic. There shall be an external boundary to the system. An external boundary is determined by what aspect of system performance is of concern. This is stated here because for quantitative hazard analysis, boundary definition is extremely important. Also, the interface part needs to be considered (See Fig. V/3.0-l). The process definition for qualitative risk analysis is Qualitative Risk Analysis assesses the priority of identified risks using their probability of occurring, the corresponding impact [...] as well as other factors such as the time frame and risk tolerance [..On the contrary, quantitative risk analysis (QRA) as per DNV is Typically, a QRA can be defined as the formal and systematic approach of identifying potentially hazardous events, estimating the likelihood and consequences of those events, and expressing the results as risk to people, the environment or the husiness. ... [Pg.303]

Rigorous analysis of electronic wavefunctions strives to extract the maximum amount of easily interpretable information while minimizing the number of arbitrary definitions invoked in the quantification of chemical concepts. In order to achieve this end, such analysis must employ only those theoretical formalisms that satisfy the following conditions. First of all, each quantitative definition has to be universally applicable... [Pg.893]

Fault Tree Analysis. Fault trees represent a deductive approach to determining the causes contributing to a designated failure. The approach begins with the definition of a top or undesired event, and branches backward through intermediate events until the top event is defined in terms of basic events. A basic event is an event for which further development would not be useful for the purpose at hand. For example, for a quantitative fault tree, if a frequency or probabiUty for a failure can be deterrnined without further development of the failure logic, then there is no point to further development, and the event is regarded as basic. [Pg.473]

The word concentration is frequently used as a general term referring to a quantity of substance in a defined volume of solution. But for quantitative titrimetric analysis use is made of standard solutions in which the base unit of quantity employed is the mole. This follows the definition given by the International Union of Pure and Applied Chemistry1 in which ... [Pg.259]

The limit of detection (LOD) (see Figure 2.6) is defined as the smallest quantity of an analyte that can be reliably detected. This is a subjective definition and to introduce some objectivity it is considered to be that amount of analyte which produces a signal that exceeds the noise by a certain factor. The factor used, usually between 2 and 10 [11], depends upon the analysis being carried out. Higher values are used for quantitative measurements in which the analyst is concerned with the ability to determine the analyte accurately and precisely. [Pg.42]


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See also in sourсe #XX -- [ Pg.327 ]




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Analyses, definition

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