Effect of Metal Contamination

Smaiier fragments are eventuaiiy degraded as weii. This first chromatogram uses a new DNASep coiumn, Buffer A 1 M TEAA, pH 7.0, buffer B 1 M TEAA, pH 7.0 with 25% v/v acetonitriie, gradient, 0 min 35% B, 3 min 55% B, 10 min 55% B, andl2minl00%B. 

Metal ion contamination, such as colloidal iron, can be released from frits, travel to other parts of the HPLC, and then be trapped. These types of contaminants will interfere with DNA in solution or after it has been released and trapped on a critical component of the H PLC such as the colurrui, an inline filter in front of the detector, or at a back-pressure device located after the detector. 

Iron(lll) and other metals can form insoluble complexes with phosphate anion. It is likely that surface metal ions and/or colloidal iron are combining with one or more phosphate groups on the nucleic add fragments. If this happens, the ion-pair process chromatographic separation can be interrapted, causing the peaks to broaden. In extreme cases, it is possible that this metal contamination is so severe that nucleic acid fragments are completely prevented from eluting from the system and no peaks are detected. 

All of these improvements are incorporated into commercial instruments designed for nucleic acid chromatography. It is also important to follow preventive maintenance procedures and check filters for signs of colored deposits. Since double-stranded DNA is more susceptible to contamination, the use of precautions with respect to the method and the system is much more critical than when the 

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Burridge, J.C. and Berrow, M.L.B. (1984) Long-term effects of metal-contaminated sewage sludges on soils and crops. In Proceedings of the International Conference on Environmental Contamination, London, CEP Consultants, Edinburgh, pp. 215-224. 

One of the roles of the matrix is to reduce the effect of metal contamination. Various matrices have been proposed to be suitable for this purpose. Magnesia-alumina has been found to be superior to most other inorganic oxides as a vanadium and nickel metal trap as well as increasing the resistance of the zeolite Y to steam deactivation [4]. 

Spurgeon, D.J. and Hopkin, S.P. (1996) The effects of metal contamination on earthworm populations around a smelting works - quantifying species effects. Applied Soil Ecology, 4, 147-160. 

Roark, S. and Brown, K. (1996) Effects of metal contamination from mine tailing on allozyme distributions of populations of great plain fishes. Environ. Toxicol. Chem., 15, 921-927. 

Metal bioavailability is an important parameter in determining the effectiveness of metal-contaminated soils in remediation. Assessment of metal bioavailability varies from humans to plants to microbes, and as such, various methods have been developed for a specific purpose. In this section we provide an overview of various methods used to determine the effectiveness of P-induced Pb immobilization. Reduction of Pb bioavailability by PR was demonstrated by feeding-trial and plant-uptake studies (Laperche et al., 1996). Hydroxyapatite and PR effectively... 

Effect of Metal Contamination on the Heat Stability of Polymers... 

Light, mechanical shock, heat, and certain catalysts can be initiators of explosive reactions. Hydrogen and chlorine react explosively in the presence of light. Examples of shock-sensitive materials include acetylides, azides, organic nitrates, nitro compounds, perchlorates, and many peroxides. Acids, bases, and other substances can catalyze the explosive polymerizations. The catalytic effect of metallic contamination can lead to explosive situations. Many metal ions can catalyze the violent decomposition of hydrogen peroxide. 

Falster, Robert. Gettering in Silicon Fundamentals and Recent Advances. Semiconductor Fabtech 13 (2001). This article provides a thorough description of the effects of metal contamination in silicon and the process of gettering to avoid the damage that results from such contamination. 

Metallic The effects of metallic contaminants on the plated deposits and the maximum levels allowable are as follows copper darkness, 5 to 10 ppm cadmium dullness, 50 ppm zinc dullness, 50 ppm nickel streaks, 50 ppm iron dullness, 50 to 120 ppm and chromium... 

At high metals levels, the coking characteristics of a cracking catalyst can be greatly increased that is, the ratio of contaminant coke to catalytic coke can be quite high. The effect of the contaminant metals on the coke response is affected not only by the level of metals but also by the type of catalyst and the use of a metals passivator. Catalysts, which contain effective metals traps to inhibit the contaminant effects, do produce much less contaminant coke than catalyst without metal traps. 

Sandrin, T. and Hoffman, D., Bioremediation of organic and metal co-contaminated environments Effects of metal toxicity, speciation, and bioavailability on biodegradation, in Environmental Bioremediation Technologies, Singh, S.N. and Tripathi, R.D., Eds, Springer, Berlin, Germany, 2007, pp. 1-34. 

Hardiman R.T., Banin A., Jacoby B. The effect of soil type and degree of metal contamination upon uptake of Cd, Pb and Cu in bush beans. Plant Soil 1984b 81 3-15. 

The effects of other contaminants in the feed stream was tested using ammonia and ethylene-diaminetetraacetic acid (EDTA). While ammonia had little effect on the effectiveness, EDTA affected efficiency significantly. When the metals were complexed with EDTA, they broke through almost immediately, making the capacity of the media to remove metals not significant... 

Waste oil, although contaminated, has a high energy value, and burning as a fuel is a major outlet for used oil. Unfortunately, used oil contains high concentrations of metallic contaminants, and its combustion can cause adverse environmental effects. Some of the metallic materials in used motor oils are introduced during use. Typically, the metals introduced by means of wear or corrosion are aluminum, copper. 

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