In Mexico

Iodine occurs to a minute extent (less than 0.001 %) in sea water, but is found in greater concentration, combined in organic form, in certain seaweeds, in oysters and in cod livers. Crude Chile saltpetre, or caliche contains small amounts of sodium iodate, NalOj. from which iodine can be obtained (see below). Some insoluble iodides, for example liiose of silver and mercury(II), occur in Mexico. Iodine is found in the human body in the compound thyroxin in the thyroid gland deficiency of iodine in diet causes enlargement of this gland (goitre). 

Fig. 1. A "barred olivine" chondrule from the Allende-type CV chondrite that feU in Mexico in 1979. The transmitted polarized light image of the 0.5 mm-diameter chondrule was taken from a poHshed thin section. The bars are composed of oHvine, (Mg,Fe)2Si04. The interstitial material is glass quenched...

Sesame Seed (Benne, Benni, Bene Seed). Sesame seed is the whole dried seed of Sesamum indicum L. (PedaUaceae), an annual plant now cultivated in Mexico and Central America, although indigenous to Indonesia and tropical Africa. It may be the oldest condiment known. The seed is small, shiny, and oval shaped, about 0.32 cm long. The unhuUed seeds are dark and the hulled seeds are pearly white. Sesame seeds, when baked, have a pleasant, roasted, nutty flavor. They are used in baked goods and in confections, eg, halvah. 

In the early 1980s mine capacity approached a level of 136,000 t/yr Mo, far more than demand. Several mines have since closed. As of the early 1990s total molybdenum capacity remained well above total demand of about 90,000 t/yr. Estimated 1993 production in units of metric ton of molybdenum was in Armenia, 450 t in Canada, 10,000 t in Chile, 15,000 t in China, 16,000 t in Iran, 1,400 t in Kazakhstan, 1,400 t in Mexico, 1,800 t in MongoHa, 1,400 t in Pern, 2,700 t in Russia, 5,000 t in Uzbekistan, 900 t and in the United States, 37,000 t. 

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. 

Before scmbbing procedures were estabUshed for copper ore, most of the rhenium was lost as the volatile (Re202). A small portion, perhaps 10%, was retained in flue dust, which was processed to give the metal. A commercial flotation (qv) process for the recovery of the molybdenite by-product is available that permits a high recovery of molybdenum and rhenium. This process is used at the Caridad copper mine in Mexico. 

The discovery of aqua regia by the Arab alchemist Jabir Ibn Hayyan (ad 720—813) provided a new extraction technology. Amalgamation of silver in ores with mercury was extensively used during the late fifteenth century by the Spaniards in Mexico and BoLvia. In 1861 the complex ores of the Comstock Lode, Nevada, were ground together with mercury, salt, copper sulfate, and sulfuric acid, and then steam-heated to recover the silver. 

U.S. silver production from 1985 to 1994 averaged 1588 t/yr. Less than one quarter of this output comes from silver mine districts, however. About half is as by-product of gold mines about one quarter comes from copper and lead—2inc mines. The silver production in Mexico from 1985 to 1994 averaged 2256 t/yr, and Pern, at the southern extremity of the cordillera, where silver is a by-product of copper and lead—2inc mines, averaged 1810 t/yr. 

Deposits of celestite in Gloucestershire, the United Kingdom, represented the main source of the world supply from 1884 to 1941 and provided up to 90% of the world strontium supply (4). During World War II, shipments to the United States and Western Europe from the United Kingdom were dismpted, and celestite deposits in Mexico and Spain were developed. 

As of 1996, Solvay Barium Strontium GmbH was the world s largest producer of strontium carbonate at its combined barium—strontium plant at Bad Hunningen (Germany). Cia Minera La Valencia (Mexico) was the next largest producer, followed by Chemical Products Corporation of the United States, which has two plants, one in the United States and one in Mexico. Dachan Specialty Chemicals (South Korea) was another principal producer. Together these four companies accounted for almost 80% of world capacity. 

There are two main processes for conversion of celestite, ie, strontium sulfate, to strontium carbonate. The principal process is the black ash process. Strontium nitrate is produced by dissolving celestite in nitric acid and purifying it. Most other strontium compounds are produced from strontium nitrate. To service this market, NOAH Technologies Corporation (San Antonio, Texas) has estabUshed a plant in Mexico to manufacture most commercial- and reagent-grade strontium compounds except strontium carbonate. 

From a bioavailabihty standpoint, the fact that a significant amount of nicotinic acid is in a bound form has important biological consequences. Poor bioavailabihty stems from the fact that the ester linkage is resistance to digestive enzymes. In the case of com, this condition can be alleviated if com is pretreated with alkah. This food preparation method is frequently practiced in Mexico for the preparation of tortillas. 

Equipment and material normally amount to about 40 to 45 percent of the costs of a typical chemical plant. In general, equipment and material costs are ghtly cheaper in European countries and Japan, whereas in Mexico and Canada they are nearer the United States average. 

In the United States and in Mexico there has been recent renewed interest in the guayule shrub as a source of natural rubbber. Whilst this shrub could provide an indigenous source of supply to these countries the rubber is more difficult to obtain. At present it is necessary to pull up the bush, macerate it, extract the rubber with solvent and then to preeipitate it from solvent. 

The fire and explosions in Mexico City in 1984, which killed more than 500 people (see Section 8.1.4), started with a pipe failure. The cause is not known, but the pipe may have been subjected to excessive pressure. Earlier the same year, in February, at least 508 people, most of them children, were killed in Cubatao, Sao Paulo, Brazil, when a 2-ft-diameter... 

Comprised of 27 Constituent Societies (23 in the US., two in Canada, and one each in Mexico and the United Kingdom), the international membership also includes affiliated members from over 45 countries. Members represent the diverse segments involved in coatings —from formulation and testing to manufacture and sales. 

The online director) to chemicals and chemical companies in Mexico and South America. Includes links to companies. 

LPG in Mexico City consists of 50% by volume propane and 50% butane in the liquid phase, and of 80% and 20%, respectively, in the vapor phase. (Limited information is available on the actual LPG composition at the time of the accident.)... 

It does not seem likely that the liquid flashed explosively, because the actual overpressure at 300 m in Mexico City was estimated to be below 3 kPa. This conclusion is consistent with the findings of Pietersen, although he assumed that... 

First mineral bromide (bromyrite, AgBr) discovered in Mexico by P. Berthier — later also found in Chile... 

The first iodine-containing mineral (Agl) was discovered in Mexico in 1825 but the discovery of iodate as an impurity in Chilean saltpetre in 1840 proved to be more significant industrially. The Chilean nitrate deposits provided the largest proportion of the world s iodine until overtaken in the late 1960s by Japanese production from natural brines (pp. 796, 799). 

Cold-hammering was used in the late Stone Age to produce plates of gold for ornamental purposes, and this metal has always been synonymous with beauty, wealth and power. Considerable quantities were accumulated by ancient peoples. The coffin of Tutankhamun (a minor Pharaoh who was only 18 when he died) contained no less than 112 kg of gold, and the legendary Aztec and Inca hoards in Mexico and Peru were a major reason for the Spanish conquests of Central and South America in the early sixteenth century. Today, the greatest hoard of gold is the 30000 tonnes of bullion (i.e. bars) lying in the vaults of the US Federal Reserve Bank... 

Samples of the oil distilled in Mexico have been oxamiued hy Schimmel A Go. ... 

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