Search results for "Aggregate stability"
showing 6 items of 6 documents
Polysorbate 80 controls Morphology, structure and stability of human insulin Amyloid-Like spherulites
2022
AbstractAmyloid protein aggregates are not only associated with neurodegenerative diseases and may also occur as unwanted by-products in protein-based therapeutics. Surfactants are often employed to stabilize protein formulations and reduce the risk of aggregation. However, surfactants alter protein-protein interactions and may thus modulate the physicochemical characteristics of any aggregates formed. Human insulin aggregation was induced at low pH in the presence of varying concentrations of the surfactant polysorbate 80. Various spectroscopic and imaging methods were used to study the aggregation kinetics, as well as structure and morphology of the formed aggregates. Molecular dynamics s…
Effect of biochar on the physical and structural properties of a sandy soil
2019
Abstract Biochar application to soil can be considered as a means to improve soil quality, thereby optimizing irrigation management and reducing irrigation needs, especially in dryland regions. This paper is aimed at investigating the effect of biochar (BC) on a desert sandy soil (Al Foah, United Arab Emirates) in terms of bulk density, porosity, water retention, plant available water (AWmax), aggregate stability (AS) and specific surface area (BET-SSA). BC was produced from forest biomass (Italy). Soil water retention was measured by the High Energy Moisture Characteristic (HEMC) and by pressure plate measurements, by using BC fractions equal to 0 (soil only), 0.014, 0.091, 0.23, 0.33 and …
Cementing agents involved in the macro- and microaggregation of a Mediterranean shrubland soil under laboratory heating
2014
The heating effect on aggregation and cementing agents of a Mediterranean soil was studied in two fractions (macro- and microaggregates) in different environments: under Quercus coccifera soil (UQ), under Rosmarinus officinalis soil (UR) and between plants or bare soil (BS). Samples were heated under laboratory conditions at different temperatures (220, 380, 500, 750 and 1000. °C) to establish their effects on the studied soil properties by comparison with unheated control samples (25. °C). Increasing temperature treatments caused significant changes in most soil variables. In both soil fractions, the presence of vegetation contributed to increase of the soil organic matter (SOM) content, w…
Contribution of raindrop impact to the change of soil physical properties and water erosion under semi-arid rainfalls
2017
Soil erosion by water is a three-phase process that consists of detachment of soil particles from the soil mass, transportation of detached particles either by raindrop impact or surface water flow, and sedimentation. Detachment by raindrops is a key component of the soil erosion process. However, little information is available on the role of raindrop impact on soil losses in the semi-arid regions where vegetation cover is often poor and does not protect the soil from rainfall. The objective of this study is to determine the contribution of raindrop impact to changes in soil physical properties and soil losses in a semiarid weakly-aggregated agricultural soil. Soil losses were measured und…
Soil quality indicators as affected by a long term barley-maize and maize cropping systems
2011
Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L.) and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L.) with Italian ryegrass (R3) and grain-maize maintained in these conditions for 18 years. Each crop system was submitted to two management options: 1) the high input level (H), done as a conventional tillage, 2) the low input level (L), where the tillage was replaced by harrowing and the…