Effects Of Hydration Conditions Research Articles

Effect of hydration conditions in thermal and mechanical properties of injection-molded glass fiber/polyamide-6

Effect of hydration conditions in thermal and mechanical properties of injection-molded glass fiber/polyamide-6

Microbial dispersal in unsaturated porous media: Characteristics of motile bacterial cell motions in unsaturated angular pore networks

AbstractThe dispersal rates of self‐propelled microorganisms affect their spatial interactions and the ecological functioning of microbial communities. Microbial dispersal rates affect risk of contamination of water resources by soil‐borne pathogens, the inoculation of plant roots, or the rates of spoilage of food products. In contrast with the wealth of information on microbial dispersal in water replete systems, very little is known about their dispersal rates in unsaturated porous media. The fragmented aqueous phase occupying complex soil pore spaces suppress motility and limits dispersal ranges in unsaturated soil. The primary objective of this study was to systematically evaluate key factors that shape microbial dispersal in model unsaturated porous media to quantify effects of saturation, pore space geometry, and chemotaxis on characteristics of principles that govern motile microbial dispersion in unsaturated soil. We constructed a novel 3‐D angular pore network model (PNM) to mimic aqueous pathways in soil for different hydration conditions; within the PNM, we employed an individual‐based model that considers physiological and biophysical properties of motile and chemotactic bacteria. The effects of hydration conditions on first passage times in different pore networks were studied showing that fragmentation of aquatic habitats under dry conditions sharply suppresses nutrient transport and microbial dispersal rates in good agreement with limited experimental data. Chemotactically biased mean travel speed of microbial cells across 9 mm saturated PNM was ∼3 mm/h decreasing exponentially to 0.45 mm/h for the PNM at matric potential of (for , dispersal practically ceases and the mean travel time to traverse the 9 mm PNM exceeds 1 year). Results indicate that chemotaxis enhances dispersal rates by orders of magnitude relative to random (diffusive) motions. Model predictions considering microbial cell sizes relative to available liquid pathways sizes were in good agreement with experimental results for unsaturated soils. The new modeling platform enables quantitative consideration of key biophysical factors (e.g., pore space heterogeneities and hydration conditions) governing microbial interactions in 3‐D soil pore spaces.

Steam hydration of CFBC ash and the effect of hydration conditions on reactivation

A detailed study has been carried out on how hydration methods and conditions influence the sulphur capture potential of ash from a 165 MWe circulating fluidized bed combustion boiler firing a petroleum coke and coal blend. Both bed ash and fly ash were hydrated with saturated steam at various saturation conditions for different periods of time. Samples of the hydrated residues were then analyzed for free lime and calcium hydroxide content after the hydration process. Some size fractions of the steam-hydrated samples and those hydrated with liquid water in previous work were re-sulphated for 90 min using synthetic flue gas in a thermogravimetric analyzer at 850 °C to investigate how reactivation conditions affect the final sulphur capture behaviour of the ash. This work confirms that either hydration method is effective for reactivating the bed ash fractions tested but not fly ash, which should either be re-injected directly or reactivated in some other manner to improve its sulphur capture potential.

Effect of Hydration Conditions on the Physical Properties of Fly Ash-Ca(OH)2 Sorbents

Fly ash samples taken from three different coal-fired power plants in Turkey were used as reagent material for the production of reactive sulfur dioxide sorbents. For this purpose, fly ash-Ca(OH)2 mixtures with different weight ratios were hydrated under different conditions. The effects of the hydration conditions such as temperature, time, and fly ash/Ca(OH)2 weight ratio on the physical properties of activated sorbents were investigated. A statistical design technique was applied by use of two-level factorial design matrix to interpret experimental results. It was found that increasing the temperature and hydration time caused an increase in the total surface area of the sorbents. However, except for one case, surface area values were generally not changed significantly for sorbents obtained from mixtures that have different fly ash/Ca(OH)2 weight ratios.

The effects of temperature and buffer on fibrinogen adsorption from blood plasma to glass

[125I]-Fibrinogen was used to measure the adsorption of fibrinogen from baboon plasma to two types of glass (Pyrex and a borosilicate glass) at 25 and 37 degrees C using two different buffers to dilute the plasma, the first being citrate-phosphate buffered saline (CPBSz) and the second isotonic Tris-saline (TRIS), both pH 7.4. In addition, the effects of hydration conditions, rinsing techniques, and glass-cleaning treatments on fibrinogen adsorption were evaluated. The data reveal that lower temperatures and the use of TRIS to dilute the plasma significantly enhance fibrinogen adsorption to both types of glass. As has been observed in the past, fibrinogen adsorption peaked at intermediate plasma concentrations on both Pyrex and borosilicate glass (the so-called Vroman effect), but almost twice as much fibrinogen adsorbed to glass when TRIS was used to dilute the plasma instead of CPBSz. Moreover, up to five times as much fibrinogen adsorbed to both types of glass at 25 degrees C compared with 37 degrees C. No effects of the rinsing technique or glass-cleaning treatment were observed.

Effects of hydration conditions on the stroma inclusion of some CAM chloroplasts

Abstract The tubular protein inclusion of the chloroplasts of some CAM plants was found to maintain its normal pattern of accumulating by day and dissolving at night when the hydration state of the chloroplasts was reversed by promoting influx of water during the day and efflux of water during the night. Morphometric study of the chloroplast inclusion of Sedum telephium supports our suggestion that the behaviour of the aggregate of tubules is independent of the water content of the chloroplasts.

Effects of hydration conditions on the stroma inclusion of some CAM chloroplasts

Effects of hydration conditions on the stroma inclusion of some CAM chloroplasts