Increased restrictiveness

A goal of reducing total mercury releases in the United States by 33% between 1988 to 1992, and 50% by 1995 was set by the EPA. The 1992 goal was more than achieved United States reportable mercury releases were reduced by 39% by 1991 (26). In the United States, discards of mercury in municipal soHd waste streams were approximately 643 t in 1989 (3). As a result of increased restrictions on the use and disposal of mercury, by the year 2000 mercury in municipal soHd waste streams is expected to be about 160 t (3). 

Industry and transport contribute another 1.5 X 1011 kg of the dioxide, of which about 70% comes from oil and coal combustion—mainly in electricity-generating plants. Because, like many other countries, both the United States and Canada have increased restrictions on emissions of sulfur oxides, emissions of S02 into the atmosphere in Canada fell 50% between 1980 and 2000 and in the United States they fell 40% during the same period (see Box 10.1). 

Similarly, increasing restrictions on discharge and deep welling could significantly reduce their potential for cost-effective waste handling. 

The efficacy of IV thrombolysis in patients with moderate-to-severe strokes due to proximal arterial occlusions is restricted by several factors, including the relatively short therapeutic window, poor recanalization rates as the clot burden increases, restrictive eligibility criteria, and the risk of intracerebral hemorrhage. Endovascular techniques improve the rates of recanalization in this patient population, and appear to increase the likelihood of a good functional outcome. Intravenous thrombolysis... 

In 1998, approximately 30% of all gasoline in the United States contained oxygenates. At that time, MTBE was the most common fuel oxygenate, present in more than 80% of oxygenated fuels. However, due to increasing restrictions on the use of MTBE, this percentage has decreased over the past several years. In 1998, ethanol was the second most common fuel oxygenate, present in about... 

The overall result of environmental awareness has been to increase the interplay of devolution and evolution. Devolution has seen increasing restrictions, sometimes amounting to a complete ban, on the use of certain substances (e.g. alkylphenolethoxylates, which were once widely used) and a corresponding evolution of new products which, at least for the present, are environmentally acceptable. This interplay between devolution and evolution is likely to continue indefinitely. Environmental factors as they affect specific types of auxiliary will be dealt with under the relevant sections of this volume. 

Dichromate oxidation does tend to give a harsher handle and a less hydrophilic fibre, tending to cause handling problems in subsequent processes such as weaving, and is therefore less suitable for yarn dyeings. The technical merits of dichromate are overshadowed by ecological considerations, however, since chromium compounds in surface waters pose a direct threat to health and are increasingly restricted by water treatment... 

Soil-applied pesticides have been successfully used to control soilbome diseases, weeds, and nematodes in most vegetable and fruit crops over the past decades. Toxicity of these materials to animals and humans and their environmental and economic costs (Pimentel et al. 1992 Ruzo 2006) raised serious environmental and human safety concerns, leading to the phase-out of the most effective and largely used chemical, the methyl bromide (Luken and Grof 2006), and the increasing restrictions on the applications of available pesticides (Perkins and Patterson 1997). The limited availability of chemicals resulted in an increased emphasis on... 

Freedom from toxicity is clearly the primary consideration for dyes used in foods, drugs and cosmetics, followed by high solubility and chemical stability in the appropriate medium of incorporation. The possibility that they may affect consumers adversely has caused growing concern [59,60]. Legislation over many years has increasingly restricted the usage of synthetic colorants to certain permitted products that have shown no harmful effects when tested rigorously. 

The shift from straight oils to synthetics has resulted mainly from machine improvement and increased restrictions on the disposal of oil and grease. Thus, metalworking fluids have been modified with water to minimize disposal problems and with chemicals to preserve the fluids and to accom modate higher speeds while increasing tool life. 

Registration requirements for purchasing, possessing, and using explosives have been revised with increased restrictive requirements in recent years [149]. Increased scrutiny and regulation of commercially available components of lEDs can be anticipated. 

As with organic-matrix composites, advances with MMCs are continually being made to answer the call for better materials meet ever increasingly restrictive requirements and ever-broadening applications. 

In the interest of even-handedness, the author has adopted the term gun control advocates to refer to those seeking to maintain or to increase restrictions on... 

Increasing restrictions also apply to the chloride process, so that efforts are continually being made to use the iron chloride byproduct, e.g., in water treatment and as a flocculation agent [2.56], Another process for treating metal chorides with cement and alkaline compounds to produce rock-like aggregates for road building is described in [2.57]. 

In zeolites the mobility of hydrocarbon molecules with double bonds is specifically restricted because of a specific interaction between the 7r-elec-trons and the zeolite (2). As expected, proton spin relaxation of benzene, cyclohexadiene, cyclohexene, and cyclohexane adsorbed on NaY reveals an increasing restriction of mobility with increasing number of -electrons (8, 4, 8). This is shown in Figure 1, where the longitudinal (7 ) and transverse (T2) proton relaxation times are plotted. 

Nearly half (46 percent) of the bark producedwas used as fuel, 10 percent for other purposes—mainly for soil application, and 44 percent was not used (6) Bark was utilized least of all types of residues. And bark disposition is becoming more of a problem due to the increased restrictions on the incineration of bark residues. 

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