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Sparse collection

Production, Use, Release and Disposal. Available data indicate that most nitrobenzene produced in the United States is consumed in the production of aniline, but current quantitative data on the amount of nitrobenzene released to the environment during nitrobenzene production and use are sparse. Collection of this information would be helpful in evaluating the effect of current industrial practices on environmental levels of nitrobenzene. [Pg.63]

What is the most difficult research job in all of science It is the task of deducing the history of Earth s evolution in its first two billion years, during the Hadean eon from 4.5 to 4.0 Ga (IGa = 10 years before present) and the Archean eon from 4.0 to 2.5 Ga. Detectives of ancient rocks are faced with a lack of clues to investigate. Most of Earth s surface is covered by water. The cores of the continents are probably underlain by rocks older than 2.5 Ga but they are hidden by a veneer of younger sediments. Even in localities where Hadean-Archean rocks are readily available, alteration by subsequent geologic events has obscured the record of conditions under which they were formed. It is revealing to compare and contrast the detailed information available in a textbook of Earth s modem ecologies with the sparse collection of facts accepted by disciplinary consensus for the Hadean-Archean eras. [Pg.262]

This chapter has presented a rather sparse collection of directly measured heats of formation. The data have been supplemented by a significantly larger collection of derived numbers, analogies and estimation principles. The measured and derived values were further combined in a self-consistent manner that allowed for the prediction of the heats of formation of sulphonic acids, sulphonate esters, sulphonamides and sulphonyl chlorides. [Pg.316]

In special applications people have built telescopes with very sparse arrays of mirrors in order to sample the resolution space with minimum number of mirrors. Systems like this may give greater angular resolution (longer baseline) but have less sensitivity due to the smaller collecting area. [Pg.66]

In the case of a copper-zinc and copper-lead-zinc ore, gold collects in the copper concentrate. During the treatment of lead-zinc ores, the gold tends to report to the lead concentrate. Information regarding gold recovery from base metal ores is sparse. [Pg.14]

It has been proposed that a sparse matrix provides superior coverage to the selection of apparently optimal diversity reagents. However, the final collection of molecules that... [Pg.407]

The Committee analyzed published studies describing the In vivo and in vitro properties of the agents used and reviewed short-term data collected by the U.S. Army on volunteers. The ability to provide definitive answers to the questions raised by the charge to the Committee was limited by the absence of long-term followup studies of the soldiers and by the sparseness of chronic effects studies of these compounds In animals or In humans after industrial exposure. [Pg.13]

The general chemistry of the thiocoumarin system has only been sparsely examined, leaving large uncharted areas of even the most basic kind. The known chemistry is collected below. [Pg.124]

Shih and Lin (2003) investigated the solidification/stabilization of arsenic-rich flyash from an abandoned copper smelter in northern Taiwan. The flyashes (2-40 % total arsenic, mostly as As(III)) were collected from three flue gas discharge tunnels. Extremely high cement dosages (cement/waste mass ratio of greater than 6) were required to stabilize the wastes so that they would pass the US TCLP for arsenic (<5 mg L 1 Appendix E). (The TCLP is often used in research outside of the United States.) Cement dosages could be reduced and the mixtures would still pass the TCLP for both arsenic and lead if municipal waste incinerator flyash was added. Lime alone was able to stabilize arsenic and pass the TCLP however, the leachates exceeded the TCLP lead standard of 5mgL 1. The immobilization of arsenic in lime may be due to the formation of sparsely water-soluble calcium arsenites and arsenates, such as CaHAsC>3 //1LO or Ca3(AsC>4)2 H20, where n > 0 (Shih and Lin, 2003, 692). [Pg.404]

The high percent of unaccounted spray is likely due to filtration of the spray by foliage, and not to drift or evaporation. The effect was pronounced in the Ocala sand pine, a more densely foliated species than the slash pine. Dense foliage acts as fibers in a filter. As the number of fibers increase there are fewer open spaces for drops to penetrate without colliding with a fiber, in this case a needle. As the foliage collects drops at the upper crown there are fewer available to the lower crown levels. These results suggest that pines, even with their sparse foliage compared to spruce and fir, are efficient collectors of spray drops. [Pg.127]

A data structure was created by combining PK and PD data from three clinical studies. In double-blind, randomized, placebo-controlled, parallel-group, 2 week Phase III studies performed in the target patient population, sparse blood samples were collected for population pharmacokinetic analysis (Table 6). [Pg.742]

Dalton s own observations led him to accept the idea that air was a mechanical mixture of gases. Yet the composition of the atmosphere was constant. His records proved that without question. He had analyzed the atmosphere taken from hundreds of different places m England—from the tops of mountains, over lakes, in valleys, in sparsely settled regions and in crowded cities. Yet the composition was the same. Gay-Lussac in France had ascended m a balloon filled with hydrogen to an altitude of 21,375 feet over Paris, and had collected... [Pg.80]

The total land area of the PV electrolysis plant ranges from 94 mi2 to 68 mi2 for 10% and 14% efficient PV respectively. The land area is not a problem since PV electrolysis plants will be located in sparsely populated desert regions. Annual water consumption is 1.47-billion gallons, which is a relatively small quantity of water and is easily supplied by either on-site, rain-runoff, collection and storage systems or water importation by train or truck. [Pg.302]


See other pages where Sparse collection is mentioned: [Pg.29]    [Pg.17]    [Pg.163]    [Pg.1197]    [Pg.29]    [Pg.17]    [Pg.163]    [Pg.1197]    [Pg.351]    [Pg.544]    [Pg.383]    [Pg.337]    [Pg.50]    [Pg.137]    [Pg.176]    [Pg.318]    [Pg.208]    [Pg.255]    [Pg.540]    [Pg.557]    [Pg.162]    [Pg.22]    [Pg.531]    [Pg.568]    [Pg.309]    [Pg.237]    [Pg.453]    [Pg.337]    [Pg.189]    [Pg.75]    [Pg.356]    [Pg.348]    [Pg.131]    [Pg.51]    [Pg.573]    [Pg.86]    [Pg.104]    [Pg.599]    [Pg.136]    [Pg.31]   
See also in sourсe #XX -- [ Pg.154 ]




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Collecting a Sparse Symmetric Matrix

Sparse

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