on the source of plasma density and electric field perturbations in pmse and pmwe regionspolar mesospheric summer/winter echoes (pmse/pmwe) are very strong radar echoes produced by ionospheric electron density fluctuations at half the radar wavelength. the main focus of this paper is the altitude range 80 to 90 km in summer and altitude range 65-86 km in winter in the polar mesosphere . this pa...

in this study, the effects of moisture content and corn variety on the physicochemical properties of popcorn were investigated and modeled using response surface methodology. each of the two corn varieties (hybrid corn ksc 600 pc and american) was prepared with a range of moisture (six moisture levels ranging from 10 to 20%) and popped by a hot air popper. variety and moisture content affected ...

background: bio aerosols include airborne micro-organisms such as bacteria, fungi, viruses, etc and their products. exposure to a bio aerosol is linked with a broad spectrum of health problems, including infectious diseases, acute toxic effects, allergies, and cancer. the aim of this study was to evaluate the quality and quantity of bio aerosols found in the air of different wards in valiasr ho...

Background: Bio-aerosols in the air of hospital wards have an important role in the development of infections. It is important to make quantitative and qualitative estimations of microorganisms in the air of these wards as an index for environmental hygiene applicable to different hospital wards. The aim of the study was to investigate degrees of diversity and density of bio-aerosols in the ed...

1D3D and 2D2D cyclones were tested at Amarillo, Texas, to evaluate the effect of air density on cyclone performance. Both airflow rate and cyclone inlet velocity change with the change in air density. Two sets of inlet design velocities determined by the different air densities were used for the tests: one set based on the actual airflow, and the other set based on standard airflow. Experimenta...

introduction: the process of urbanism in countries that are developing, like islamic republic of iran with increasing of the number and the size of cities and the fast accepting of population have been caused the forming of problems like an in-official economics and in-official settlement and was become creating high population in main and old places of city and increasing of air pollution and ...

We use panel data from Germany to analyze the effect of population density on urban air pollution (nitrogen oxides, particulate matter, ozone, and an aggregate index for bad quality [AQI]). To address unobserved heterogeneity omitted variables, we present long difference/fixed effects estimates instrumental variables estimates, using historical soil as instruments. Using our preferred find that...

We study the effect of urban density on exposure city dwellers to air pollution using data from United States system. Exploiting geological features instrument for density, we find an economically and statistically significant pollution-density elasticity 0.14. assess health implications these estimates that increased in average leads sizeable mortality costs. Our findings highlight possible tr...

Background: Bio aerosols include airborne micro-organisms such as bacteria, fungi, viruses, etc and their products. Exposure to a bio aerosol is linked with a broad spectrum of health problems, including infectious diseases, acute toxic effects, allergies, and cancer. The aim of this study was to evaluate the quality and quantity of bio aerosols found in the air of different wards in Valiasr Ho...