Preparation inadequate

Surface preparation, always important in obtaining optimal coatings performance, is critical for marine coatings (see Metal surface treatments). Surface preparation usually comprises about half of the total coating costs, and if inadequate may be responsible for early coating failure. Proper surface preparation includes cleaning to remove contaminants and roughening the surface to faciUtate adhesion. 

Skins with bonded doublers have been used successfully on a large number of civil aircraft and are still used on new designs. The only widespread in-service problem with bonded doubler assemblies has been delamination caused by unstable surface preparation. Early fuselage skins with bonded doublers and inadequate surface preparation experienced severe delamination and subsequent corrosion. A majority of these delaminated doublers were the fail-safe tear straps (Fig. 27). Although the tear strap bond does not cany structural load, the bond... 

Penetration of rust through an otherwise intact paint film is usually a result of inadequate surface preparation before painting, especially over weathered and hand-cleaned steel. However, superficial rust staining may be traceable to dissolved iron salts, e.g. in bilge water from a ship s deck. 

A consideration of the most important causes of paint failure must include the following inadequate surface preparation, application of the paint... 

Paints are one of the most important methods of corrosion control, but it is well known that many cases of failure result from inadequate surface preparation of the metal and careless application of the paint system procedures that are often carried out under adverse or unsuitable environmental conditions by labour that is relatively unskilled. A great deal of research and... 

One of the strengths of Schild analysis is the capability of unveiling nonequilibrium conditions in experimental preparations such as inadequate time of equilibration or removal of drugs from the receptor compartment. Figure 6.11 shows a range of possible experimentally observed but problematic linear Schild regressions that could be encountered for competitive antagonists. 

Hensley ei al.,n reported the only direct experimental observation of head-to-head linkages in PS by 2D INADEQUATE NMR on, 3C-enriched PS. The method did not enable these groups to be quantified with sufficient precision for evaluation of W tc- Zammit el a/.130 studied chain distribution of low molecular weight PS prepared with AIBN initiator by MALDI-TOF. Separate distributions of chains formed by combination and disproportionation were observed. They estimated kJkK. at 90 °C to be 0.057. 

The quality control of both diphtheria and tetanus vaccines requires that the products are tested for the presence of free toxin, that is for specific toxicity due to inadequate detoxification with formalin, at the final-product stage. By this stage, however, the toxoid concentrates used in the preparation of the vaccines have been much diluted and, as the volume ofvaccine that can be inoculated into the test animals (guinea-pigs)... 

In the 1980s, CdSe quantum dots vere prepared by top-dovm techniques such as lithography ho vever, size variations, crystal defects, poor reproducibility, and poor optical properties of quantum dots made them inadequate for advanced applications. Introduction of bottom-up colloidal synthesis of CdSe quantum dots by Murray et al. [3] and its further advancements brought radical changes in the properties of quantum dots and their applications in devices and biology. The colloidal syntheses of CdSe quantum dots are broadly classified into organic-phase synthesis and aqueous-phase synthesis. 

For whom is this book intended For those involved in industry, particularly nonchemical operations), who have, for a long while (since the application of the Labour Code) had much experience in safety matters, but for whom my experience as a trainer in the department of Hygiene, Safety and Environment of the lUT allows me to say how inadequately prepared they are when confronted with certain aspects of risk chemistry. Public organisations, curiously, had, until recently, no obligation to administer the Labour Code and that which concerned hygiene and workers safety. This book is concerned with all these activities but is not addressed to all safety officers because it presupposes a basic knowledge of chemistry. For all that, the chemist may not be at ease with this book, which he may find difficult. For this reason, numerous examples are provided to illustrate the methods studied, and assist in their application, and to permit him to identify the limits. 

This method proved inadequate in the parathion studies because of trace contaminations and the following procedure of sample preparation was adopted ... 

When a patient wants to use a dietary supplement, the following points should be addressed inadequate regulations for quality, safety, or efficacy, differences in preparations from different manufacturers, and insufficient reporting of adverse events. 

According to EPA (1986a), lead was used in preparations sold as abortifacients in Britain around the turn of the century. These preparations were apparently effective at levels that produced marked signs of lead poisoning in the women. The available studies were methodologically inadequate and did not provide dose-effect information. Evidence for adverse reproductive outcomes in women with obvious lead poisoning is of little help in defining the effects of lead at much lower exposure levels. 

Dining attempted preparation of trimethyl orthoformate, addition of sodium to an inadequately cooled chloroform-methanol mixture caused a violent explosion. See Ethanol (or methanol), Potassium sulfide, above See Sodium methoxide, below... 

Of extremely low stability explosions occurred during its preparation if cooling was inadequate [1], or on exposure to light [2],... 

A 200 g sample, prepared by addition of substrate to mixed acid, followed by quenching into water, filtration and washing, decomposed vigorously at a late stage of drying in a vacuum oven, which was pressurised and the seal forced open. This behaviour might have been due to inadequate washing and residual sulfuric acid. 

Benzyl cyanide was prepared from the chloride and sodium cyanide in aqueous methanol. Inadequate cooling of the reactor led to a fire. 

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