We have developed a multifocus confocal Raman microspectroscopy system that allows simultaneous analyses of ≈ 80 individual biological or airborne microparticles based on a precise image-guided technique. Multiple individual particles adhered in random positions on a coverslip were illuminated by a multifocus excitation pattern formed by rapidly steering a single laser beam with a pair of galvo...

A unique agar drum sampler is described which indicates, continuously, the number of viable, bacterial particles per unit volume of air at the time and point of sampling. By selection of the timer and the sampling rate the sampler is suitable for quite a wide range of concentration and time. An impaction line of 484 in. greatly increases the capacity of this device over slit samplers and other ...

A portable laser radar system was installed at Manora Peak, Nainital (29° 22’ N, 79°27’ E, 1960 m MSL) under a scientific collaborative programme between National Atmospheric Research Laboratory (NARL), Gadanki and Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital. The laser radar system provides the extinction of vertical distribution of airborne particles in the atmosp...

Premature infants in neonatal intensive care units (NICUs) have underdeveloped immune systems, making them susceptible to adverse health consequences from air pollutant exposure. Little is known about the sources of indoor airborne particles that contribute to the exposure of premature infants in the NICU environment. In this study, we monitored the spatial and temporal variations of airborne p...

Intercomparisons of aerosol particle number concentrations measured with various condensation particle counters (CPCs) during the first Aerosol Characterization Experiment (ACE 1) are made to assess the accuracy of the airborne measurements. When no ambient 3-10 nm diameter particles (nanoparticles) were present, median concentrations from four CPCs on the National Center for Atmospheric Resear...

Particle mass and number measurements in a church indicate significant increases of indoor particle concentrations during the burning of incense. Generally, varying concentration regimes can be attributed to different "modes of indoor activity" and emission sources. While periods of candle burning are negligible concerning particle concentrations, increases by a factor of 6.9 and 9.1 during inc...

Since the investigation of wear particles in rail transport started in late-1910s, the high mass concentration of these particles has raised worries among researchers concerned with air quality. However, effective action has yet to be taken because of lack of relevant knowledge. This thesis provides applicable information for the airborne wear particles in rail transport. Some aspects of their ...

When airborne particles are inhaled it is known that most of those of effective diameter greater than about 5 ,u are filtered out by the upper respiratory tract. Current knowledge of this subject as reviewed by Davies (1949, 1952) indicates that the size of particle which has a 50% chance of passing through the upper respiratory tract lies somewhere in the range 312t to 5 t±. Toxic effects from...

When designing a cleanroom to achieve a required airborne cleanliness class or grade, such as specified in the International Organization for Standardization (ISO) 14644-11, or the European Union Guidelines to Good Manufacturing Practice (EU GGMP)2, designers have a problem in deciding how much filtered air should be supplied to the cleanroom. Currently, this is not normally calculated but base...