the nafion 117 membrane was doped with sio2 particles by sol-gel reaction. the reaction conditions to minimize leaching were investigated by using full factorial design of experiment. the results from the full factorial analysis indicated that the lowest amount of leaching takes place at 60oc without addition of acid and swelling of membranes prior to the reaction. the membranes, prepared at op...

wheat, cv. alvand, under late sowing condition and comparison with conventional sowing date was investigated in a field experiment in 2009-2010. the factors were seven levels of priming by sa, including control or untreated seeds, 400, 800, 1200, 1600, 2000 and 2400 µm sa and two sowing dates including conventional sowing date (23 october) and late sowing (22 november). results showed that prim...

We examine the temperature dependence of the interfacial molecular structure at the water-air interface by combining experimental and simulated sum-frequency generation (SFG) spectroscopy. The experimental SFG spectra of the OH-stretching mode show a decrease in the amplitude at ∼3300 cm(-1) with increasing temperature, while the 3700 cm(-1) 'free OH' SFG feature is insensitive to temperature c...

soil temperature is one of the most effective parameters for plant growth. although the spatiotemporal monitoring of soil temperature is important for providing an optimum condition to maximize the yield efficiency, indirect measurements for zoning  of soil temperature are essential due to difficulties in direct methods of measuring it and also the limited measurement points. thus, the efficien...

Temperature gradients exist in the field under brackish water irrigation conditions, especially in northern semi–arid areas of China. Although there are many investigators dedicated to studying the mechanism of brackish water irrigation and the effect of brackish water irrigation on crops, there are fewer investigations of the effects of temperature gradient on the water–salt transport. Based o...

Shark populations are declining globally, yet the movements and habitats of most species are unknown. We used a satellite tag attached to the dorsal fin to track salmon sharks (Lamna ditropis) for up to 3.2 years. Here we show that salmon sharks have a subarctic-to-subtropical niche, ranging from 2 degrees to 24 degrees C, and they spend winter periods in waters as cold as 2 degrees to 8 degree...

Based on both static (extended Köhler) and dynamic modelling, we investigate the influence of temperature, humidity, HNO(3) initial concentration, as well as of the particle concentration, on the efficiency of HNO(3)-mediated laser-induced condensation. This mechanism is most efficient for low temperatures, high HNO(3) concentration, and relative humidities. It is, however, still active up to 3...

A variety of microbes inhabit extreme environments. Extreme is a relative term, which is viewed compared to what is normal for human beings. Extreme environments include high temperature, pH, pressure, salt concentration, and low temperature, pH, nutrient concentration and water availability, and also conditions having high levels of radiation, harmful heavy metals and toxic compounds (organic ...

Changes in water temperature can have important consequences for aquatic ecosystems, with some species being sensitive even to small shifts in temperature during some or all of their life cycle. While many studies report increasing regional and global air temperatures, evidence of changes in river water temperature has, thus far, been site specific and often from sites heavily influenced by hum...

Temperature-dependent rotational diffusion of tetraethylene glycol dimethyl ether (TEGDE) is measured by optical heterodyne-detected optical Kerr effect (OHD-OKE) spectroscopy and compared to previous measurements of rotational diffusion as a function of water content. Both types of data, temperature-dependent and hydration-dependent, follow the Debye-Stokes-Einstein (DSE) equation and agree qu...