Quality assurance constituents

Wise SA (1993) Standard reference materials for the determination of trace organic constituents in environmental samples. In Barcelo D, ed. Environmental Analysis Techniques, Applications and Quality Assurance, pp 403-446. Elsevier Science Publishers, Amsterdam, The Netherlands. Wise SA, and Schantz MM (1997) Standard reference materials for the determination of trace organic contaminants in environmental samples. In Clement R and Siu M, eds. Reference Materials for Environmental Analysis Making and Using Them, pp 143-186. Lewis Publishers, Boca Raton, FL. 

Horwitz W, Kamps LR, Boyer KW (1980) Quality assurance in the analysis of foods for trace constituents. J Assoc Off Anal Chem 63 1344... 

In the discussion that follows, the SIMCA method is illustrated by applying it to three problems (1) quality assurance of chromatography data, (2) classification of unknowns, and (3) predicting the composition of unknown samples. This third problem is one of deconvolution of a mixture and calculation of the relative concentration of the constituents (25. 38). 

The instruments and techniques outlined in the Section on Quality assurance of NPL gas standards are used to check the concentrations of all gaseous constituents in the standards other than the specified minor and major components. This verifies that no impurities or extraneous species have become entrained into the cylinders during the preparation... 

R. FRANZ, Migration of plastic constituents, in Plastic packaging materials for food — Barrierfunction, mass transport, quality assurance and legislation, O.-G. Piringer, A. L. Baner (editors), Chapter 10, Wiley VCH, Weinheim, 2000, 287-357. 

Polygalaceae), Virginia (Aristolochia serpentaria, Aristolochiaceae) and white snakeroot (Eupatorium rugosum, Asteraceae). In the United States, a list of standardized common names called Herbs of Commerce (American Herbal Products Association, 1992) was adopted by the FDA as the only permitted source for common names on product labeling. Products that contain plants not listed in Herbs of Commerce are required to use the correct Latin name of the plant on the label. In addition to difficulties with nomenclature, problems have arisen because of the difficulty in determining exactly which plants are present in a finished product. Capsules that contain more than one plant and/or a dried crude extract make identification of the plant(s) by traditional means such as microscopy virtually impossible (Betz et al., 1995). Determination of the identity of a misidentified plant then becomes a matter of looking for specific toxic chemical constituents, which is usually a needle in a haystack approach unless symptoms are characteristic of a particular compound. Good quality assurance of raw material obviates the need for this detective work. 

Individual volumes in the series Medicinal and Aromatic Plants - Industrial Profiles provide both industry and academia with in-depth coverage of the major medicinal and aromatic plants of industrial importance in a genus. Each volume discusses key tooics such as plant sources and their commercial cultivation, chemical constituents, quality assurance, pharmacological properties, toxicology, application and market trends relevant to the genus. 

The laboratories who do CLP analyses for inorganic constituents have to maintain an extensive Quality Assurance program. This includes analysis of duplicates, laboratory blanks, interference checks, and laboratory control samples. However, the prescribed Quality Assurance does not always transfer to the laboratory bench. Also at times, routine analytical procedures will not yield the chemical information that is necessary for aqueous modeling. The following points out when these problems occur and what steps the researcher needs to take to insure data adequate for modeling. 

To think that one chemical compound would be the sole pheromone constituent is to underestimate biological complexity. From a quality assurance standpoint, reliance on the appearance of one chemical for a function as critical as reproduction would place a species in a very vulnerable position to predators who could easily mimic a single chemical. Instead, pheromones may consist of three or more chemical compounds, mixed in correct proportions (Birch, 1978). Some of these compounds may come from other environmental sources such as plant hosts. And, in addition, the effectiveness of pheromones in the natural enviromnent may be enhanced by visual shapes, colors, and textures corresponding to natural plant targets of insects. Chemical communication thus exists as a system rather than as an isolated unit. 

In this chapter, an extensive reference is made only to the inspection and testing program on the constituent materials delivered in the plant (aggregates, bitumen, etc.) and on the final product, namely, the asphalt. Information about items (a) to (c), as well as more information about (d) and additional quality assurance procedures can be found in CEN EN 13108-21 (2008). 

IV.ll. If it is not possible according to individual national practices to clearly identify one responsible party or organization, the constituent parts and interfaces of an overall quality assurance programme must be clearly understood, documented and agreed by all parties including competent authorities when appropriate. 

IV.20. All constituent parts of the quality assurance programme developed and maintained by the company should be systematically produced in the form of appropriate written documents. 

The constituents of the extracts are generally represented by a complex mixture of compounds and it is practically impossible within quality assurance to take account of all constituents of an herbal extract, apart from the fact that in most cases the complete spectrum of constituents is far from being known or analytically detectable. Reproduction and control of a defined spectrum of constituents can only be based on those substances or groups of substances that, according to the state of scientific knowledge, are pharmaceutically, pharmacologically, or toxicologically relevant. 

Medical textiles are classified in Scheme 6.1. This scheme detailing constituents of various polymeric substances (eg, natural or synthetic) and their construction processes as outlined in the previous section is important in defining medical textiles aptly. Similarly, testing the properties and performance of medical textiles with suitable methods under accredited standards is essential. Thus, it is worthwhile to adequately describe all test methods, performance testing features, results analysis, and presentation guidelines of test results prior to marketing and commercialization of a device or product. This is done so that care and quality assurance of medical textiles will be documented appropriately, which benefits users. 

The instrumentation and control system of the JRR-3M consists of its constituent systems of neutron instrumentation, process instrumentation, reactor power control, reactor protection, engineered safety feature stating and process radioactivity monitoring The system is designed and constructed under the laws, standards and criteria of those days with a satisfactory quality assurance program A specific feature of the system is an extensive introduction of computer systems with a process computer and a management computer This contributes to lightening operators loads satisfactorily... 

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