America, North

In the Sub-tropical and Tropical belts, the maximum rainfall, associated with the trade winds, is received by the southeastern Atlantic part of the continent (1,000-1,200 mm or more). To the west, the rainfall decreases sharply the Mexican plateau, the central basin and the Californian peninsula, influenced by the cold current, received from 300 to 100 mm or less annual rainfall. 

The combination of latitudinal thermal belts and longitudinal zones of wetting in the plains creates a diversity of moisture-temperature conditions and consequently formation of different ecosystems with varying biogeochemical cycling. 

This part of Tundra ecosystems covers the northern coasts of the continent and the southern part of the North American archipelago. In the north it is bounded by the Arctic desert and in the south by the Boreal Taiga Forest ecosystems. 

As in Eurasia, the southern boundary of the Tundra ecosystems in North America deviates considerably from strictly latitudinal direction. In Labrador, cooled by the cold current, and on the shores of cold Hudson Bay, the Tundra ecosystems penetrate south to 54° N. To the west of Hudson Bay, with the increasing continentality of the climate, the boundary between Tundra and Boreal Taiga Forest ecosystems is 

The biogeochemical features of Tundra ecosystems are similar to those described for the Eurasian continent (see Table 1). 

Production in the US is on a par with the Far East which has recently overtaken the USA in nameplate eapaeity. The USA is also slightly larger than the expanded European Union which has major integrated petrochemical operations in Belgium, The Netherlands, Germany and the UK. 

The product slate from cracking natural gas liquids is dominated 

The approximately 40 cracking operations are owned by various corporate entities. Some have several plants across the US. As well as US majors (Chevron-Phillips, Exxon-Mobil, Dow Chemical, Equistar), several foreign organisations operate crackers in order to have better access to the US market. Notables amongst these are BASE-Eina (EU), Formosa Petrochemical (Taiwan) and Sasol (South Africa). 

Of the more than 40 US cracking operations, most are world scale with an average capacity of over 700,000t/y. The US has some of the largest plants in the world with several in excess of 1 million tonnes and one with over 2 milUon tonnes capacity. Table 1.1 gives a list of the ethylene cracking operations, the operators, their location and nameplate capacity in 2008. 

The only issue of concern is the reliance on the ready supply of natural gas liquids and the price of the gas used in their production. 

In 1996, 22 farm workers were hospitalised while harvesting grapes after being poisoned by drift during the application of pesticides in a nearby cotton field. 

Another 225 workers were estimated to have been exposed to the pesticide mixture of chlorpyrifos, fenpropathrin and profenofos. The mixture of symptoms included vomiting and eye and nose irritation. 

Pesticide Action Network North America Updates Service, September 1996 

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Grangeat P. Description of a 3-D reconstruction algorithm for diverging X-ray beam., Radiol. Soc. North. America Conf Proc., Nov.1985. 

The near drum corrosion problem is relatively newly identified in Scandinavia. This paper presents the experience from many years of inspections in North America. 

As with synchrotron x-rays, neutron diffraction facilities are available at only a few major research institutions. There are research reactors with diffraction facilities in many countries, but the major ones are in North America, Europe and Australia. The are fewer spallation sources, but there are major ones in the United States and the United Kingdom. 

Discovered in 1803 by Wollaston, Palladium is found with platinum and other metals of the platinum group in placer deposits of Russia, South America, North America, Ethiopia, and Australia. It is also found associated with the nickel-copper deposits of South Africa and Ontario. Palladium s separation from the platinum metals depends upon the type of ore in which it is found. 

Osmium occurs in iridosule and in platinum-bearing river sands of the Urals, North America, and South America. It is also found in the nickel-bearing ores of Sudbury, Ontario region along with other platinum metals. While the quantity of platinum metals in these ores is very small, the large tonnages of nickel ores processed make commercial recovery possible. 

Pubhc sector aquaculture involves production of aquatic animals to augment or estabUsh recreational and commercial fisheries. PubHc sector aquaculture is widely practiced in North America and to a lesser extent in other parts of the world. The FAO definition of aquaculture also indicates that farming implies ownership of the organisms being cultured, which would seem to exclude pubhc sector aquaculture. 

Economic Aspects. There were 31 OSB plants in the United States in 1994 and these produced 6.625 x 10 m of OSB products (2). This industry is growing rapidly in both Canada and the United States. In fact, many of the composite mills currently under constmction are designed to produce OSB or similar products based on strands. Outside of North America, where building practices are not yet extensively utilizing the distinct advantages of the stud wall and plywood/OSB sheathing, there are only a few operating OSB plants. There are also small export markets for OSB products in Europe and the Far East. 

Most of the world s acetone is now obtained as a coproduct of phenol by the cumene process, which is used by 21 of 31 producing companies in North America, Western Europe, and Japan. Cumene is oxidi2ed to the hydroperoxide and cleaved to acetone and phenol. The yield of acetone is beheved to average about 94%, and about 0.60—0.62 unit weight of acetone is obtained per unit of phenol (13). 

The largest production of acrylamide is in Japan the United States and Europe also have large production faciUties. Some production is carried out in the Eastern Bloc countries, but details concerning quantities or processes are difficult to obtain. The principal producers in North America are The Dow Chemical Company, American Cyanamid Company, and Nalco Chemical Company (internal use) Dow sells only aqueous product and American Cyanamid sells both Hquid and sohd monomer. In Europe, Chemische Eabrik Stockhausen Cie, Ahied CoUoids, The Dow Chemical Company, and Cyanamid BV are producers Dow and American Cyanamid are the only suppHers to the merchant market, and crystalline monomer is available from American Cyanamid. Eor Japan, producers are Mitsubishi Chemical Industries, Mitsui Toatsu, and Nitto Chemical Industries Company (captive market). Crystals and solutions are available from Mitsui Toatsu and Mitsubishi, whereas only solution monomer is available from Nitto. 

Pipe and fittings remain a significant market for ABS, particularly in North America. ABS foam core technology allows ABS resin to compete effectively with PVC in the primary drain-waste and vent (DWV) pipe market. 

Early demand for chlorine centered on textile bleaching, and chlorine generated through the electrolytic decomposition of salt (NaCl) sufficed. Sodium hydroxide was produced by the lime—soda reaction, using sodium carbonate readily available from the Solvay process. Increased demand for chlorine for PVC manufacture led to the production of chlorine and sodium hydroxide as coproducts. Solution mining of salt and the avadabiHty of asbestos resulted in the dominance of the diaphragm process in North America, whereas soHd salt and mercury avadabiHty led to the dominance of the mercury process in Europe. Japan imported its salt in soHd form and, until the development of the membrane process, also favored the mercury ceU for production. 

The price differential at which coal becomes competitive with gas depends on plant size and the cost of capital, but based on estimates by the International Energy Agency (21) the required price ratio for gas to coal in North America falls into the range of 3.1 to 3.7 on an equivalent energy basis ( /MJ). Current prices give a gas/coal cost ratio nearer 1.5 to 2.0. As a result, all projected new methanol capacity is based on natural gas or heavy oil except for the proposed coal-based plant in China. 

The market for optical fiber worldwide in 1992 was 2.8 billion corresponding to 10 million fiber kilometers (Mfk) (38). This can be broken down into the U.S. market (3.7 Mfk), the rest of North America (0.4 Mfk), northern Europe (4.1 Mfk), eastern Europe (2.6 Mfk), the Pacific Rim (2.8 Mfk), and elsewhere (0.3 Mfk). Most of the optical fiber is manufactured by only a few companies, the largest of which are AT T and Coming. Other producers include Alcatel, Eujikura, Eurakawa, Northern Telecom, Pirelli, and Sumitomo. The market for optical fibers is projected to reach 3.5 biUion by 1998. In addition, according to ElectroniCast (San Mateo, Ca.), the total market for passive optical components, optical electronics, connectors, and fiber-optic cable is predicted to increase from 1.76 billion (U.S.) in 1992 to over 4 billion in 1997, and 10 billion by 2002. 

A worldwide Hst of spandex fiber and related elastomer producers is shown in Table 2. Most process developments have occurred in the United States, Germany, Japan, and Korea. A large proportion of worldwide capacity is controlled by Du Pont, either directly or through subsidiaries and joint ventures. These include three plants in North America, two in South America, two in Europe, and two in Asia. 

Approximately 2.5 million t of viscose process regenerated ceUulose fibers were produced in 1990 (Table 1). Measured by production capacity in 1990, the leading producers of filament yams in 1990 were the Soviet Union state-owned factories (255,000 t capacity) and Akzo Fibres in Europe (100,000 t). The leading producers of staple fiber and tow were Courtaulds with 180,000 t capacity spUt between the UK and North America Formosa Chemicals and Fibres Co. with 150,000 t in Taiwan Tenzing with 125,000 t in Austria, and a 40% stake in South Pacific Viscose s 37,000 t Indonesian plant and Grasim Industries in India (125,000 t). BASF s U.S. capacity of 50,000 t was acquired by Tenzing in 1992. 

Such repositioning inevitably means reduced production volume, and for the first time this century production in the last decade has been below that a decade earUer (Eig. 9). Most capacity reductions have been in North America and especiaUy eastern Europe. This has been offset in part by capacity increases in the Ear East. Rayon is no longer a significant component of carpets, and has lost the disposable diaper coverstock business to cheaper and more easUy processed polypropylene. It has, however, gained share in health and hygiene products and is now a principal component of tampons worldwide. 

The ores of most importance are fluorspar, CaF2 fluorapatite, Ca (P0 2Fj cryoHte [15096-52-3], Na AlF. Fluorspar is the primary commercial source of fluoiine. Twenty-six percent of the world s high quaHty deposits of fluorspar are ia North America. Most of that is ia Mexico. United States production ia 1987—1991 was 314,500 metric tons, most of which occurred ia the Illinois-Kentucky area. Imported fluorspar ia 1990—1991 represented about 82% of U.S. consumption 31% of U.S. fluorspar imports were from Mexico and 29% from China compared to 66% from Mexico ia the 1973—1978 period. The majority of the fluorine ia the earth s cmst is ia phosphate rock ia the form of fluorapatite which has an average fluorine concentration of 3.5%. Recovery of these fluorine values as by-product fluorosiHcic acid from phosphate production has grown steadily, partially because of environmental requirements (see Phosphoric acid and THE phosphates). 

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