Area Discovery

Research and development. When research and development are used together, it refers to the broadest definition for research (see above). Some people use the term research colloquially to include most or all of the scientific and medical areas (discovery, evaluation, and development) covered by the single term research and development. Medicine development has several definitions and, in its broadest definition, is exactly the same as the broad definition of research. 

Collapse of sides Falling materials from sides Falls into the excavation Undermining of structures in the area Discovery of underground services Access and egress to the excavation Fumes and lack of oxygen Occupational health considerations... 

For more than a century petroleum geologists have been looking for oil. During this period major discoveries have been made in many parts of the world. However, it is becoming increasingly likely that most of the giant fields have already been discovered and that future finds are likely to be smaller, more complex, fields. This is particularly true for mature areas like the North Sea. 

The adliesion and fiision mechanisms between bilayers have also been studied with the SEA [M, 100]. Kuhl et al [17] found that solutions of short-chained polymers (PEG) could produce a short-range depletion attraction between lipid bilayers, which clearly depends on the polymer concentration (fignre Bl.20.1 It. This depletion attraction was found to mduce a membrane fusion widiin 10 minutes that was observed, in real-time, using PECO fringes. There has been considerable progress in the preparation of fluid membranes to mimic natural conditions in the SEA [ ], which promises even more exciting discoveries in biologically relevant areas. 

The use of sensitizing dyes in photography has been the subject of many studies and constitutes. still now. one of the most studied areas in specialized periodic publications (125, 126) or in textbooks (88. 127). It can be ascertained that one hundred years after Vogel s discovery of spectral sensitization, the basic mechanisms of action of dyes on their silver halide support still remain not fully understood. However, the theoretical reasons explaining why among many other dye families practically only cyanine methine dyes appear to be spectral sensitizers (128) are better known. 

If metallic electrodes were the only useful class of indicator electrodes, potentiometry would be of limited applicability. The discovery, in 1906, that a thin glass membrane develops a potential, called a membrane potential, when opposite sides of the membrane are in contact with solutions of different pH led to the eventual development of a whole new class of indicator electrodes called ion-selective electrodes (ISEs). following the discovery of the glass pH electrode, ion-selective electrodes have been developed for a wide range of ions. Membrane electrodes also have been developed that respond to the concentration of molecular analytes by using a chemical reaction to generate an ion that can be monitored with an ion-selective electrode. The development of new membrane electrodes continues to be an active area of research. 

More recently, studies of wine and beer have initiated techniques of statistically vaUd sensory analysis. Scientific studies involving wine continue in these areas, building on past discoveries. Natural phenols as desirable dietary components and monitors of storage and aging reactions are currently active fields. Viticultural research, as well as enological, continues to improve grapes and the wines made from them (11). 

The decrease in petroleum and natural gas reserves has encouraged interest in and discovery and development of unconventional sources of these hydrocarbons. Principal alternatives to conventional petroleum reserves include oil shale (qv) and tar sands (qv). Oil shale reserves in the United States are estimated at 20,000 EJ (19.4 x 10 Btu) and estimates of tar sands and oil sands reserves are on the order of 11 EJ (10 x 10 Btu) (see Tarsands Shale oil). Of particular interest are the McKittrick, EeUows, and Taft quadrangles of Cahfomia, the Asphalt Ridge area of Utah, the Asphalt, Kentucky area, and related geographic regions. 

Ana.lytica.1 Methods. Since 1984, dramatic technical advances have been made in the analysis of trace organic chemicals in the environment. Indeed, these advances have been largely responsible for the increased pubUc and governmental awareness of the wide distribution of herbicides in the environment. The abiUty to detect herbicides at ppb and ppt levels has resulted in the discovery of trace herbicide residues in many unexpected and unwanted areas. The realization that herbicides are being transported throughout the environment, albeit at extremely low levels, has caused much pubUc and governmental concern. However, the pubUc health implications remain unclear. 

AH cephalosporins found in nature (Tables 1 and 2) have the D-a-aminoadipic acid 7-acyl side chain (21). AH of these compounds can be classified as having rather low specific activity. A substantial amount of the early work in the cephalosporin area was unsuccessfiiHy directed toward replacing the aminoadipic acid side chain or modifying it appropriately by fermentation or enzymatic processes (6,22). A milestone ia the development of cephalosporins occurred in 1960 with the discovery of a practical chemical process to remove the side chain to afford 7-ACA (1) (1). Several related processes were subsequendy developed (22,23). The ready avaHabHity of 7-ACA opened the way to thousands of new semisynthetic cephalosporins. The cephalosporin stmcture offers more opportunities for chemical modification than does that of penicillins There are two side chains that especiaHy lend themselves to chemical manipulation the 7-acylamino and 3-acetoxymethyl substituents. 

Such trace impurities can actually determine the activity or selectivity of a catalyst. However, this serious problem ia catalyst reproducibiUty can also offer leads toward discovery of new catalytic species, and a promising area of catalyst research iavolves ferreting out which active trace impurities are determining the performance of estabhshed catalysts. 

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