Since climate has a major impact on dust generation, it is essential to identify the climatic parameters affecting this phenomenon. In this study, climatic parameters including temperature, relative humidity, rainfall, maximum wind speed and direction were selected and their relationship with visibility data and also dust storm days (recorded at meteorological stations) was analyzed on monthly ...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

The present study aimed to compare the effect of land cover on runoff and sediment with different coverage levels in Mehrian watershed. The study was carried out in a plot with the dimensions 3 × 2 meters during one year, in three different treatments (including without coverage, grass treatment and integrated treatment having brush and grass coverage) and in three replications. At the end of e...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

Introduction Changes, although low in temperature, change the occurrence of extreme phenomena such as droughts, heavy rainfall and storms (Varshavian et al., 2011: 169). Reducing the daily temperature variation has led to a reduction in the frequency of occurrence of temperature minima, especially in winter (Schiffinger et al., 2003, p. 51-41). Material and method The purpose of the present ...

Monthly sampling of red algae was carried out from April 2005 to March 2006 in Chabahar coasts (southestern of Iran) along Sistan & Baluchistan province coastal waters. We considered monthly periods of maximum tide according to tide tables. Then seaweed growth area in intertidal zones was determind through GPS, GIS and satellite imagery. Monthly sampling was conducted on a number of transects w...