Contaminants, analysis

Microscopists in every technical field use the microscope to characterize, compare, and identify a wide variety of substances, eg, protozoa, bacteria, vimses, and plant and animal tissue, as well as minerals, building materials, ceramics, metals, abrasives, pigments, foods, dmgs, explosives, fibers, hairs, and even single atoms. In addition, microscopists help to solve production and process problems, control quaUty, and handle trouble-shooting problems and customer complaints. Microscopists also do basic research in instmmentation, new techniques, specimen preparation, and appHcations of microscopy. The areas of appHcation include forensic trace evidence, contamination analysis, art conservation and authentication, and asbestos control, among others. 

Metrology and contamination analysis in particular have been decisive factors for profitable semiconductor production [4.47]. Semiconductor applications of TXRF go back to the late nineteen-eighties and were introduced by Eichinger et al. [4.48, 4.49]. Because of its high sensitivity, wide linear range, facile spectrum deconvolution, and... 

BREEZE is a software package for ventilation airflows in single and muT ticefled buildings, developed by the Building Research Establishment. BREEZE also includes a contaminant analysis routine. 

The phenol-contaminated sample was unique in yielding bromine containing none of the starting contaminant. Analysis of the bromine by FT-IR and INMR showed a complex mixture of brominated phenols and small amounts of other brominated hydrocarbons. The absence of phenol in the bromine product is not surprising, since phenol reacts with bromine at room temperature to make predominantly tribromophenol. 

Bennett K, Biggs J, Fresquez P. 1996. Radionuclide contaminant analysis of small mammals, plants and sediments within Mortandad Canyon, 1994. Los Alamos, NM Los Alamos National Laboratory. LA-13104-MS UC-908 UC-902 contract no. W-7504-ENG-36 DE-96-007-463. 

Contamination can be present not only as a surface deposit or a surface feature but can also be located within the bulk of a manufactured part. The selection of an appropriate series of analytical techniques, applied to failure, defect, and contamination analysis projects, is influenced by the location of the contamination or defect and the optical properties of the manufactured component. Microscopic analysis of opaque parts is limited to surface analysis... 

If additional information pertaining to the rubber composition were sought, FTIR analysis of the pyrolysis products would have been performed. Even more detailed analysis can be obtained by gas chromatography (GC) separation of the multiple pyrolysis products followed by mass spectrometric (MS) detection. The gas chromatography-mass spectrometry (GC-MS) method is well suited to deformulation and contaminant analysis. 

This topic has been mentioned in Section V, Failure, Defect and Contaminant Analysis, in Chapter 15, where a number of typical practical problem invetsigations were presented. Obviously the potential list of examples exhibiting different characteristics and requiring a different type of analysis is lengthy. When the sample is heterogeneous, e.g., a polymer blend or a composite, the study of the surface of a failed piece of material may reveal whether the problem is the interface of the components or that failure occurred within one of these. In particular in the case of crazing or necking orientation may have been induced, the way this can be analysed is discussed in Chapter 8. 

The topics of polymorphism and pseudopolymorphism dominate the majority of publications that deal with utilizing infrared spectroscopy for the physical characterization of pharmaceutical solids. Typically, in each of the publications, IR spectroscopy is only one technique used to characterize the various physical forms. It is important to realize that a multidisciplinary approach must be taken for the complete physical characterization of a pharmaceutical solid. Besides polymorphism, mid- and near-IR have been utilized for identity testing at the bulk and formulated product level, contaminant analysis, and drug-excipient interactions. A number of these applications will be highlighted within the next few sections. 

Handy, R.D. 1992. The assessment of episodic metal pollution. II. The effects of cadmium and copper enriched diets on tissue contaminant analysis in rainbow trout (Oncorhynchus mykiss). Arch. Environ. Contam. Toxicol. 22 82-87. 

Soil for contaminant analysis (see below) As below As below As below... 

Clark JR, Devault D, Bowden RJ, et al. 1984. Contaminant analysis of fillets from Great Lakes (USA, Canada) coho salmon, 1980. Journal of Great Lakes Research 10(1) 38-47. 

DeVault DS, Weishaar JA. 1985. Contaminant analysis of 1982 Fall Run coho salmon (Oncorhynchus Kisutch). Govt Reports Announcements Index, Issue 14. 

Two particular aspects of the transport of degradable contaminants were considered in laboratory experiments that used soil originating from the field experiments described in the previous sections. Studies on diffnsion of degradable insecticides were performed in diffusion cells, while the spatial redistribntion of pesticides from a point source was measured in specially designed pans (60 cm high, 40 cm diameter). Periodic sampling and contaminant analysis enabled visnaUzation of the contaminant transport pathway. 

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