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931.
While snowflakes fell and Christmas carols heralded the imminent holiday, over 3000 delegates to the Third National Conference on Air Pollution were told to “Control Now for Clean Air.”

They were told this in many ways by many people—by the Vice President of the United States; by the Secretary of the Department of Health, Education, and Welfare who summoned the Conference; and by senators, congressmen, governors, and mayors.

Then eight panel sessions convened to discuss and to determine how to control now for clean air. Speakers from every section of American life addressed themselves to this subject; when they were finished, the eight session chairmen summarized what had been said, what had been, learned. These summaries appear on the following pages.  相似文献   
932.
933.
The feasibility of open burning under selected meteorological conditions is discussed. Meteorological provisos and nonmeteorological factors are enumerated. Topics discussed include: combustion, fuel moisture, fire hazard, forecasting, fallout and odor, and air pollution potential. A mathematical estimate of visibility reduction is described and evaluated. A procedure for estimating atmospheric ventilation is presented. The author concludes that most massive open fires result in adverse effects on either a local or areawide scale. Hence, the best meteorological decision possible is frequently one that minimizes one scale of effect at the expense of the other.  相似文献   
934.
The photochemical reaction of various olefins and nitrogen dioxide was studied under conditions of controlled temperature, pressure, and humidity in a 200 liter stirred glass reactor. The hydrocarbon concentration in the reactor during four and five hour irradiation periods was monitored with a flame ionization chromatograph. Reaction rate constants, based on three consecutive first order reactions, were calculated for reactor temperatures of 20, 25, 30, and 35 degrees centigrade. Activation energies for the three consecutive reactions were calculated from the Arrhenius equation. Branched and straight chain olefins were studied at initial concentrations of 5.0 to 10.0 parts per million.s  相似文献   
935.
936.
This progress report describes the National Air Pollution Technical Information Center currently under development in the Division of Air Pollution, Public Health Service. It briefly reviews the report "Science, Government, and Information" (Weinberg Report) and the White House delegation of responsibility to the Department of Health, Education, and Welfare for handling air pollution technical information.  相似文献   
937.
938.
939.
940.
Commercial cattle-feeding is a large industry in the United States. In California, for instance, there are more than 500 commercial feedlots. Each of these lots handles from less than 500 to more than 50,000 head of cattle at one time. With the urban and suburban explosion, feedlots that were at one time many miles from residential centers are now “just across the street.” Naturally the high odor level from improperly operated yards gives rise to considerable complaint and citizen indignation.

A variety of methods to reduce odor to an acceptable level have been tried with varying results. A highly satisfactory procedure is based on “good housekeeping” practices, frequent removal of fecal material, and abatement of residual odor by spraying the lots at designated intervals with a solution of potassium permanganate. Details of the method are discussed.  相似文献   
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