Glues, contamination

Oxygen evolved from the anodes as well as some hydrogen from the cathodes produces a mist which is trapped by a froth maintained by adding cresyhc acid, sodium siUcate, and gum arabic, or glue plus cresol. Alkaline-earth carbonates prevent lead contamination of the cathode ziac. Most of the lead is deposited ia the cell sludge as iasoluble carbonate—sulfate. 

The type of proteinaceous binder was correctly identified in all model samples. In only one case (S10), the animal glue was additionally identified, although the restorer who prepared these model samples declared that the sample contained only egg binder. It is possible that this sample was contaminated during its preparation or during laboratory treatment. The results indicate that this method does not allow reliable identification of the presence of individual egg yolk and egg white most probably it is caused by the presence of a trace of egg white that is always present in the egg yolk preparations (and vice versa) and can be detected by the highly sensitive PMM method. The identification of individual types of animal glues will never be reliable by MALDI-TOF mass spectrometry because of their similar composition the application of ESI (electrospray ionisation)-MS/MS (Section 6.5) could possibly overcome this problem. Only the fish glue, whose peptide... 

All efforts need to be made to reduce the likelihood of plasticizers (Henry et al., 1983) and other contaminants getting into one s samples. Avoid DCM making contact with the glue that attaches Teflon liners to caps, as this glue can give rise to peaks in the chromatogram. 

Table L Results of surface contamination on XRF analysis (all values are in weight percent). Glue adhering to the surface resulted in higher Zn and Fe levels, while coins that were dirty with aggregates of soil... 

Sources of contaminated water in the manufacture of products for which no wastewater discharge is allowed include wet-type debarking operations, steam or hot-water conditioning of logs, veneer drier washwater, glue equipment washwater, and certain types of preservative treatments. Only limited data are available on the quantity and characteristics of these effluents (Table III). Each source of wastewater is discussed below in terms of the problem that it presents and the technology that is available to deal with it. 

In most cases, before attempts are made to recycle plastic resins, the used parts must first go through a series of sorting processes. The purpose of these sorting processes is to separate the desired recycle plastic from possible contaminants in the incoming stream. These contaminants can take many forms. They include dirt, paper, glue, and metal as well as other recyclable plastics and even the same desired plastic but of a different color. The most postconsumer recycled plastic today is PET. This is the plastic from which all plastic soft drink beverage bottles are made. 

A distinct advantage of plastic pyrolysis into fuels as a means of recycling is its ability to handle mixed and unwashed plastics. Post-consumer plastics are often commingled and contaminated with extraneous materials such as soil, dirt, aluminium foils, paper labels and food remnants. While soil, dirt and glue can be removed from post-consumer plastics by washing, this is a fairly expensive operation and it leads to secondary waste streams... 

Alternatively, different types of glue, including epoxy or cyanoacrylate-based glues, can be used. Care has to be taken to avoid sample contamination. In particular, cyanoacrylates must not be covered during curing as they outgas material that deposits on the sample if covered. 

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