Scientific units

Ricardo Ramos, Genomic Unit, Scientific Park of Madrid, Madrid, Spain... 

UNSCEAR, Sources and effects of ionizing radiation sources and biological effects, 1982. Report to the General Assembly, with Annexes, United Scientific Committee on the Effects of Atomic Radiation. UN, New York, 1993,... 

FIGURE 8.1 Pyrolysis unit, Scientific Glass Engineering (SGE) Pyrojector. 1. Sample loading area, 2. Quartz sample tube (reaction zone), 3. Sample loading cover interlock, 4. Valve body, 5. O-ring type seal, 6. Carrier gas inlet, 7. Check valve, 8. Carrier gas vent, 9. Valve spindle, 10. Heat deflectors, 11. Micro furnace,... 

K. Bongeffer and P. Gartek, Fundamentals of Photochemistry, Moscow, United Scientific and Technical Press, 1935. 

The Opiates. The International Narcotics Control Board—Vienna, tracks the tick production of narcotic dmgs and annually estimates world requkements for the United Nations. Thek most recent pubHcation (100) points out that more than 95% of the opium for Hcit medical and scientific purposes is produced by India and, in a declining trend, only about 600 t was utilized in 1988. This trend appears to be due to the fact that the United States, the largest user of opium for alkaloid extraction, reduced the amount of opium being imported from about 440 t in 1986 to 249 t in 1987 and 224 t in 1988. The United States used about 48 t of morphine (2, R = H) in 1988, most (about 90%) being converted to codeine (2, R = CH3) and the remainder being used for oral adrninistration to the terminally ill (about 2 t) and for conversion to other materials of minor commercial import which, while clearly alkaloid-derived, are not naturally occurring. 

There is growing commercial importance and escalating scientific interest in PVDF. The World Patent database, including the United States, Hsts 678 patents that cite the term poly(vinyHdene fluoride) for the period 1963—1980 and 2052 patents for the period 1981—1992 Chemical Abstracts files covering the years 1967—1992 contain 5282 references for the same term. Thirty years ago there was only one commercial producer of PVDF in the world now there are two in the United States, two in Japan, and three in Europe. 

From the time that isoprene was isolated from the pyrolysis products of natural mbber (1), scientific researchers have been attempting to reverse the process. In 1879, Bouchardat prepared a synthetic mbbery product by treating isoprene with hydrochloric acid (2). It was not until 1954—1955 that methods were found to prepare a high i i -polyisoprene which dupHcates the stmcture of natural mbber. In one method (3,4) a Ziegler-type catalyst of tri alkyl aluminum and titanium tetrachloride was used to polymerize isoprene in an air-free, moisture-free hydrocarbon solvent to an all i7j -l,4-polyisoprene. A polyisoprene with 90% 1,4-units was synthesized with lithium catalysts as early as 1949 (5). 

Metrologia International Committee of Weights and Measures (CIPM) Pavilion de Breteuil Parc de St. Cloud, Prance Includes articles on scientific metrology worldwide, improvements in measuring techniques and standards, definitions of units, and the activities of various bodies created by the International Metric Convention. 

I. Mills, ed.. Quantities, Units, and Symbols in Physical Chemisty, BlackweU Scientific Publishing, London, 1988. 

Production of a metal is usually achieved by a sequence of chemical processes represented as a flow sheet. A limited number of unit processes are commonly used in extractive metallurgy. The combination of these steps and the precise conditions of operations vary significantly from metal to metal, and even for the same metal these steps vary with the type of ore or raw material. The technology of extraction processes was developed in an empirical way, and technical innovations often preceded scientific understanding of the processes. 

R. D. Pehlke, Unit Processes of Extractive Metallurgy, Elsevier Scientific Publishing Co., Inc., New York, 1973. 

The Federal Food, Dmg and Cosmetic (FDAC) Act defines dmgs as "...articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in man..." and "articles (other than food) intended to affect the stmcture of any function of the body of man." In the United States and elsewhere, the introduction of a new dmg is subject to a sequence of weU-defined stages of development and approval (4). Each stage involves either scientific testing or submission and preparation of data and analysis review (Fig. 2). 

Staff of Panel on Plasma Processing of Materials, United States Nation Research Council, Plasma Processing of Materials Scientific Opportunities and Technological Challenges, Books on Demand, Ann Arbor, Mich., 1994. 

The Eastman Chemical Company has pubHshed extensively in the patent Hterature (65—74) and the scientific Hterature (75—77) on processes for making poly(phenylene sulfide)- (9-(phenylene disulfide), and related copolymers. The Eastman process involves the reaction of elemental sulfur with Ndiiodobenzene to yield a phenylene sulfide polymer that also contains phenylene disulfide repeating units in the polymer. The fraction of repeating groups containing... 

General support for science and technology remains strong in the United States (19,20), but actual financial support for scientific research remains under increased pressure from competing critical needs, including health cate, crime prevention, education, pollution control, and national defense. 

W. Majewski and D. C. Miller, eds.. Predicting Effects of Power Plant Once-Through Cooling on Aquatic Systems, Technical Papers in Hydrology 20, United Nations Educational, Scientific and Cultural Organization (Unesco), Paris, 1979. 

Temperature. The kelvin is the SI unit of thermodynamic temperature, and is generally used in scientific calculations. Wide use is made of the degree Celsius (°C) for both temperature and temperature interval. The temperature interval 1°C equals 1 K exacdy. Celsius temperature, t, is related to thermodynamic temperature, T, by the following equation ... 

Scientific Assessment of Stratospheric Ocyone 1989, United Nations Environment Program and World Meteorological Organization, New York, 1989. 

The United States. Although there are American breweries more than 100 years old, the brewing industry in the United States is young. With their technical and scientific expertise, American brewers are among the leaders in the brewing industry. 

The Society of Cosmetic Chemists, with individual memberships, was founded in the United States after World War II, based on the beHef that scientific expertise and exchange were the foundations for future expansion of the cosmetic industry. Prior to that time, knowledge of cosmetic formulation was jealously guarded. Related scientific societies emerged in other countries and have since joined to form the International Federation of Societies of Cosmetic Chemists. 

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