United States reductions

A different type of economic study, initiated in 1969, used an empirical formulation to develop economic estimates of vegetation damage (6). On the thesis that hydrocarbon emissions are related to oxidant production, hydrocarbon emission data were collected from over 100 metropolitan areas in the United States. Reductions in crop yields were empirically related to these emissions, and the monetary values were calculated. The reliability of this technique was based on known effects of oxidants on crop species and on the known relationship between hydrocarbons and oxidants. There are disadvantages to the method used, and the results suffer from lack of field verification. However, the technique has obvious advantages such as ease of use and uniformity of results. It might be a prototype from which more accurate estimates can be developed. Results from two years of development are found in annual reports (6, 7) and show between 100-125 million dollars lost annually in the United States. 

Emissions of CO in the United States peaked in the late 1960s, but have decreased consistendy since that time as transportation sector emissions significandy decreased. Between 1968 and 1983, CO emissions from new passenger cars were reduced by 96% (see Exhaust CONTUOL, automotive). This has been partially offset by an increase in the number of vehicle-miles traveled annually. Even so, there has been a steady decline in the CO concentrations across the United States and the decline is expected to continue until the late 1990s without the implementation of any additional emissions-reduction measures. In 1989, there were still 41 U.S. urban areas that exceeded the CO NAAQS on one or mote days per year, but the number of exceedances declined by about 80% from 1980 to 1989. Over the same time period, nationwide CO emissions decreased 23%, and ambient concentrations declined by 25% (4). 

Since SO2 and NO2 are criteria pollutants, their emissions are regulated. In addition, for the purposes of abating acid deposition in the United States, the 1990 Clean Air Act Amendments require that nationwide SO2 and NO emissions be reduced by approximately 10 million and 2 million t/yr, respectively, by the year 2000. Reasons for these reductions are based on concerns which include acidification of lakes and streams, acidification of poorly buffered soils, and acid damage to materials. An additional major concern is that acid deposition is contributing to the die-back of forests at high elevations in the eastern United States and in Europe. 

In 1976 the United States banned the use of CFCs as aerosol propellants. No further steps were taken until 1987 when the United States and some 50 other countries adopted the Montreal Protocol, specifing a 50% reduction of fully halogenated CFCs by 1999. In 1990, an agreement was reached among 93 nations to accelerate the discontinuation of CFCs and completely eliminate production by the year 2000. The 1990 Clean Air Act Amendments contain a phaseout schedule for CFCs, halons, carbon tetrachloride, and methylchloroform. Such steps should stop the iacrease of CFCs ia the atmosphere but, because of the long lifetimes, CFCs will remain ia the atmosphere for centuries. 

Secondary alcohols (C q—for surfactant iatermediates are produced by hydrolysis of secondary alkyl borate or boroxiae esters formed when paraffin hydrocarbons are air-oxidized ia the presence of boric acid [10043-35-3] (19,20). Union Carbide Corporation operated a plant ia the United States from 1964 until 1977. A plant built by Nippon Shokubai (Japan Catalytic Chemical) ia 1972 ia Kawasaki, Japan was expanded to 30,000 t/yr capacity ia 1980 (20). The process has been operated iadustriaHy ia the USSR siace 1959 (21). Also, predominantiy primary alcohols are produced ia large volumes ia the USSR by reduction of fatty acids, or their methyl esters, from permanganate-catalyzed air oxidation of paraffin hydrocarbons (22). The paraffin oxidation is carried out ia the temperature range 150—180°C at a paraffin conversion generally below 20% to a mixture of trialkyl borate, (RO)2B, and trialkyl boroxiae, (ROBO). Unconverted paraffin is separated from the product mixture by flash distillation. After hydrolysis of residual borate esters, the boric acid is recovered for recycle and the alcohols are purified by washing and distillation (19,20). 

The two procedures primarily used for continuous nitration are the semicontinuous method developed by Bofors-Nobel Chematur of Sweden and the continuous method of Hercules Powder Co. in the United States. The latter process, which uses a multiple cascade system for nitration and a continuous wringing operation, increases safety, reduces the personnel involved, provides a substantial reduction in pollutants, and increases the uniformity of the product. The cellulose is automatically and continuously fed into the first of a series of pots at a controlled rate. It falls into the slurry of acid and nitrocellulose and is submerged immediately by a turbine-type agitator. The acid is deflvered to the pots from tanks at a rate controlled by appropriate instmmentation based on the desired acid to cellulose ratio. The slurry flows successively by gravity from the first to the last of the nitration vessels through under- and overflow weirs to ensure adequate retention time during nitration. The overflow from the last pot is fully nitrated cellulose. 

As can be seen in Figure 8, the proportion of world pig iron produced in the United States has decreased dramatically since 1950. Also notable is the widening gap between pig iron and steel production, indicating the increasing use of recycled iron or scrap (see Recycling, ferrous metals) and alternative iron sources such as DRI and HBI. The increased demand for scrap is reflected in scrap iron prices (Fig. 9), which in turn have spurred growth in direct reduction processes. 

The amount of HEU that becomes avadable for civdian use through the 1990s and into the twenty-first century depends on the number of warheads removed from nuclear arsenals and the amount of HEU in the weapons complex that is already outside of the warheads, ie, materials stockpdes and spent naval reactor fuels. An illustrative example of the potential amounts of weapons-grade materials released from dismanded nuclear weapons is presented in Table 7 (36). Using the data in Table 7, a reduction in the number of warheads in nuclear arsenals of the United States and Russia to 5000 warheads for each country results in a surplus of 1140 t of HEU. This inventory of HEU is equivalent to 205,200 t of natural uranium metal, or approximately 3.5 times the 1993 annual demand for natural uranium equivalent. 

Unlike the common practice occurring in other countries, in which award of patent rights is based on the date on which a patent apphcation is filed, in the United States the patent grant is based on the first date of invention. To be an inventor in the United States, an individual must contribute to conception of the invention, and may contribute to reduction of the invention to practice. Although the creation of an advance, development, or apphcation may be conceived by one given individual, it often is the case that the act of invention is the work of many individuals, especially in a commercial context. Accordingly, inventorship questions often arise. 

The importance of an accurate and complete record of invention caimot be underestimated. The record of invention should serve as the basic document for estabUshing the date of conception and reduction to practice of the invention. The U.S. PTO issues patents to those who are first to invent. In a contest over inventorship, any available record of invention is submitted to the U.S. PTO to estabUsh proof of an inventor s rights. As of January 1, 1996, any inventor from a country belonging to the World Trade Organization may use such evidence before the U.S. PTO. Previously, this type of proof could be rehed upon only if the activity, documented in the notebook, record, etc, was undertaken in the United States. Similarly, activity undertaken after December 8, 1993 in Mexico or Canada may also be rehed upon to prove inventorship. 

The principal worldwide manufacturers of nylon resins are given in Table 6. Total sales of nylon plastics in the United States and Canada in 1993 were 331,000 metric tons (37). West European sales were 352,000 t and Japanese sales 220,000 t (37). Figure 7 shows how sales in the United States have steadily increased since 1967 (38) and also how the price of nylon-6,6 has changed (39). The effect of the oil price rises, the boom of the mid-1980s, as well as the oil price reduction and the recession that followed are clearly evident. Table 7 shows the variation of price across different polyamide types. 

In the United States, the reportable quantity of 1-propanol for spills under CERCLA "Superfund" is 100 Ib/d (45.4 kg/d). However, no reportable quantity is assigned for transport (43). The substance is on the list for atmospheric standards, as defined iu 40 CER 60.489 (47). The iatent of these standards is to require all newly constmcted, modified, and reconstmcted manufacturiug units to use the best demonstrated system of continuous emission reduction for equipment leaks of volatile organic compounds (47). 1-Propanol is also on the right-to-know regulations of the states of Connecticut,... 

The United States generates ca 250 x 10 scrap tines per year. In 1977, ca 52 t of reclaimed mbber and 14,400 t of cmmb mbber were produced from these tires (40). In 1980, ca 4050 t of reclaimed and cmmb mbber were used in asphalt—mbber compounds, which is less than 5% of the recycled mbber. Except for a reduction in reclaimed mbber, the 1986 production rates were higher an estimated 25,200 t of mbber were used in asphalt. 

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