Background & Aims: Human beings are constantly exposed to different radiations that have always been recognized as a health hazard. Radon -222 and its daughter products are major sources of natural radiations and a significant total inhalation dose is related to them. Hence, the measurement of radon activity in the environment has gained an increasing importance. In this study, with the measure...

The air transport industry is seeking to manage risks in air travels. Its main objective is to detect abnormal behaviors in various flight conditions. The current methods have some limitations and are based on studying the risks and measuring the effective parameters. These parameters do not remove the dependency of a flight process on the time and human decisions. In this paper, we used an HMM...

In this study rhubarb stem slices were dried as single layers with thickness of 3 mm in the inlet air temperature range of 50-70  and air velocity of 1 ± 0.2 m/s in a laboratory scale cabinet dryer. The effect of drying air temperature on the drying characteristics was determined and the relationship between the drying parameters with temperature and moisture content was examined. Moisture tran...

A persistent pulmonary air leak, whether as a result of pulmonary surgery or as a result of a traumatic or spontaneous pneumothorax, is a difficult and frustrating problem to manage. Several therapies have been employed, including thoracotomy and repair of the air leak, prolonged tube thoracostomy suction, and chemical pleurodesis. We report two cases in which patients with a prolonged air leak...

Laboratory scale biological trickling filters and three-phase airlift bioreactors have been studied for the elimination of methylene chloride (or dichloromethane) vapors from waste air, and the results used herein for the design of small industrial-scale reactors. The conditions chosen for scale-up were an air flow rate of 100 m3 h-1, a methylene chloride inlet concentration of 2 g m-3, and a t...

In a historic building with inadequate or no air conditioning or where it is not possible to install modern systems fitted with air filters, humidification, and controls, it is possible to mitigate the effects of temperature and humidity extremes on a building and its contents by controlling air-flow. When used in conjunction with mechanical air conditioning, this method can also save a little ...

A microbiological hood was designed to reduce the danger of airborne infection of laboratory workers. The hood uses absolute filters to deliver sterile air in a laminar flow to the work area. An air curtain across the hood opening permits easy access but separates the worker from aerosols produced in the hood, and protects material inside the hood from contamination by room air. Tests with bact...

Atmospheric processes affecting air quality are very complicated, and scientific understanding of these processes has been evolving rapidly. To successfully simulate concentration levels and changes of atmospheric pollutants, it is highly desirable to have air quality models with full and flexible modularity at the science process level. Such a modular air quality model would significantly enha...

Residential and commercial gaseous air cleaning technologies have not gained wide acceptance in the marketplace, in part due to the lack of performance data from field tests or simulation studies. This paper describes a field study of the performance of two gaseous air cleaners in a single room test house and simulations based on these tests with an indoor air quality model (CONTAMW). Air clean...