نتایج جستجو برای: alkalinity
تعداد نتایج: 3210 فیلتر نتایج به سال:
Saline or alkaline soils present a strong stress on plants that together may be even more deleterious than alone. Australia's soils are old and contain large, sometimes overlapping, areas of high salt and alkalinity. Acacia and other Australian plant lineages have evolved in this stressful soil environment and present an opportunity to understand the evolution of salt and alkalinity tolerance. ...
Chemical weathering and the subsequent export of carbonate alkalinity (HCO3- + CO3-2) from soils to rivers account for significant amounts of terrestrially sequestered atmospheric CO2. We show here that during the past half-century, the export of this alkalinity has increased dramatically from North America's largest river, the Mississippi. This increased export is in part the result of increas...
Simple titration methods certainly deserve consideration for on-site routine monitoring of volatile fatty acid (VFA) concentration and alkalinity during anaerobic digestion (AD), because of their simplicity, speed and cost-effectiveness. In this study, the 5 and 8 pH point titration methods for measuring the VFA concentration and carbonate system alkalinity (H2CO3*-alkalinity) were assessed and...
The defluoridation efficiency (epsilon(F)) of electrocoagulation (EC) is closely related to the pH level of the F(-)-containing solution. The pH level usually needs to be adjusted by adding acid in order to obtain the highest epsilon(F) for the F(-)-containing groundwater. The use of combined EC (CEC), which is the combination of chemical coagulation with EC, was proposed to remove fluoride fro...
We evaluated the individual and combined effects of salinity and alkalinity on gill Na+/K+-ATPase enzyme activity, plasma ion concentration, and osmotic pressure in Luciobarbus capito. Increasing salinity concentrations (5, 8, 11, and 14 g/L) were associated with an initial increase and then decrease in L. capito gill Na+/K+-ATPase activity. Activity was affected by the difference between inter...
BACKGROUND AND AIMS Salt tolerance has evolved many times independently in different plant groups. One possible explanation for this pattern is that it builds upon a general suite of stress-tolerance traits. If this is the case, then we might expect a correlation between salt tolerance and other tolerances to different environmental stresses. This association has been hypothesized for salt and ...
abstract regarding to this issue that nitrogen is one of the main essential elements for plant that growth and efficiency of plant is related to it, and on the other hand most of the water and soil resources in iran are alkaline; in order to evaluation of the interactive effect of different concentrations of sodium bicarbonate and nitrogen form on snap bean in hydroponic system, this research w...
The paper provides a basin-scale assessment of the spatiotemporal distribution of alkalinity in the Mediterranean Sea. The assessment is made by integrating the available observations into a 3-D transport–biogeochemical model. The results indicate the presence of complex spatial patterns: a marked west-to-east surface gradient of alkalinity is coupled to secondary negative gradients: (1) from m...
A new, simple and accurate method is introduced for determining H(2)CO(3)(*) alkalinity in fresh waters dominated by the carbonate weak-acid system. The method relies on a single H(3)PO(4) dosage and two pH readings (acidic pH value target: pH~4.0). The computation algorithm is based on the concept that the overall alkalinity mass of a solution does not change upon the addition of a non-proton-...
Binding-site concentration and conditional stability constants for copper and fish gill surface interactions were calculated based on the data from the literature. Six scenarios were modeled by including or excluding pH and alkalinity differences between the fish gill microenvironment and the bulk solution and the presence of free mucus in the calculation. We demonstrate that changes in pH or a...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید