Wesley J. Marshall et al. · 1977
The US Army Environmental Hygiene Agency conducted a special study of the potential retinal hazards from direct viewing of various welding processes. The study evaluated gas tungsten arc welding, gas metal arc welding, flux cored arc welding, plasma arc cutting, plasma arc welding, and shielded metal arc welding. Spectral distribution was measured from 400 nm to 1000-1100 nm for each process.
David L. Conover · 1977
Kinn JB · 1977
Unknown authors · 1977
Rats were exposed to a 39 MHz field modulated at 50 Hz with 80% modulation depth and an intensity of 30-120 w/m. Short-term exposure for 5-20 minutes disturbed avoidance reactions in 64% of rats, causing them to persistently approach a feeder despite electric shock. Longer exposures produced more pronounced and diverse disturbances in feeding reactions. During extinction, field-exposed rats required almost two times as many nonreinforced trials to extinguish the conditioned feeding response compared to controls. The behavioral disturbances were functionally reversible, with acquired habits restored within 20-25 days after exposure ended without additional training.
Curtis C. Johnson · 1977
Unknown authors · 1977
Arthur W. Guy, Michael D. Webb, John A. McDougall · 1977
Tikhonchuk VS · 1977
Frank M. Greene · 1977
The exact measurement point on the feed line is not critical, and measurements can be made at full operating power without interrupting exposure tests. In an example with 100 watts forward power and 11.1 watts reflected power, the specimen absorbed 44.4 watts, which is half the load power. The absorbed power can never exceed half the forward power, reaching this maximum when reflected power is 25 percent of forward power.
Peter E. Glaser · 1977
The paper examines design concepts for satellite solar power stations based on thermal-electric and photovoltaic conversion. The paper highlights environmental impacts including stratospheric pollution from launch vehicles and microwave beam effects.
Ezra B. Larsen, John F. Shafer · 1977
The National Bureau of Standards measured electromagnetic field intensities near typical FAA transmitters including aircraft radars, ground surveillance radars, instrument landing systems, navigation equipment, and communication antennas. Air route surveillance radars exceeded 10 mW/cm² within about 20 meters and airport surveillance radars within 15 meters, except for the newer ASR-8 model. Aircraft radars exceeded 10 mW/cm² at distances ranging from 2 to 7 meters. When antenna scanning time-averaging is considered, these field values would be greatly reduced, and near-zone beams are not normally accessible to personnel. In accessible areas, measured fields were generally less than 1 mW/cm².
T. A. Perumal, T. K. Bullard, C. Jayachandran · 1977
Researchers immobilized one hind limb of rats in a plaster cast with brass plate electrodes and applied electric pulses for six hours daily over 21 days. Tibia from both limbs were measured for dry weight, ash content, new bone deposition rate, and x-ray density. Electric fields decreased the degree of disuse bone atrophy caused by immobilization.
J. ACHIMOWICZ, A. CADER, L. PANNERT, E. WOJCIK · 1977
Unknown authors · 1977
Unknown authors · 1977
The performance standard limits microwave emission to 1 milliwatt per square centimeter at 5 centimeters from the oven surface before sale and 5 milliwatts per square centimeter thereafter. Ovens must have at least two safety interlocks, one concealed, and no single component failure may disable all interlocks. An interlock monitor that disables the oven upon interlock failure has been required on ovens manufactured since August 7, 1974.
Gandhi OP, Hagmann MJ · 1977
Frank M. Greene · 1977
James A. Hathaway et al. · 1977
Researchers evaluated over 800 ocular examinations of microwave and laser workers using multiple regression analysis. No lenticular or retinal defects were attributed to microwave or laser radiation. Minute lenticular defects increased with age. Large differences in defect recording across installations were attributed to subjective evaluation by different examiners. The authors concluded that periodic medical surveillance as conducted was nonproductive and recommended limiting it to preassignment, postaccident, and termination examinations.
Unknown authors · 1977
Unknown authors · 1977
The Second Task Force for Research Planning in Environmental Health Science produced a report identifying major and urgent research issues. The report is deliberately selective and not comprehensive.
Meterless · 1977
R. H. Lenox, J. L. Meyerhoff, O. P. Gandhi, H. L. Wray · 1977
Researchers varied microwave exposure configuration and output power to inactivate brain enzymes in rats. They studied the rate of metabolic inactivation in various brain regions by measuring cyclic AMP and phosphodiesterase activity. Exposure times needed to stabilize cyclic AMP levels differed among the hypothalamus, cortex, and cerebellum. Cyclic AMP levels in some regions decreased when inactivation was more rapid.
Unknown authors · 1977
H. Jammet et al. · 1977
Richard A. Tell, Patrick J. O'Brien · 1977
