Search results for "saturation"

The Respiratory Potential of Oxygen: A New Quantity to Characterize State, Effects and Bio-Availability of the Gas in Organism

1992

A number of quantities are known which enable to characterize the state of oxygen in blood, for instance: the concentration, which means the physically solved mass per volume; or the content, which comprises the whole mass per volume irrespective of the molecular state; or capacity, which is the chemically bound mass of oxygen per volume and, relatively, the saturation, or the oxygen partial pressure. These various quantities may be divided into two types: the mass-related and the not-mass-related ones.

2021

Abstract. Homogeneous freezing of aqueous solution aerosol particles is an important process for cloud ice formation in the upper troposphere. There the air temperature is low, the ice supersaturation can be high and the concentration of ice-nucleating particles is too low to initiate and dominate cirrus cloud formation by heterogeneous ice nucleation processes. The most common description to quantify homogeneous freezing processes is based on the water activity criterion (WAC) as proposed by Koop et al. (2000). The WAC describes the homogeneous nucleation rate coefficients only as a function of the water activity, which makes this approach well applicable in numerical models. In this study…

The use of soil water retention curve models in analyzing slope stability in differently structured soils

2017

Abstract This study analyzes whether and at what rate the parameterization of the Soil Water Retention Curve (SWRC) affects the analysis of shallow slope stability for differently structured unsaturated soils. Advanced empirical or physically-based equations of SWRCs have been proposed in literature to describe soil systems characterized by the so-called bimodal porous domain. In unsaturated soils, SWRC affects the stability assessment in two ways. It influences the resistance properties in terms of shear strengths, which depend on the soil water suction; and it affects the hydrological process modeling (e.g. infiltration) directly influencing soil moisture patterns and indirectly influenci…

Filtering for Discrete Fuzzy Stochastic Time-Delay Systems with Sensor Saturation

2013

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from Hindawi: http://dx.doi.org/10.1155/2013/146325 This paper addresses the H-infinity filtering problem for discrete fuzzy stochastic systems with time-varying delay and sensor saturation. Random noise depending on state and external disturbance is also taken into account. A decomposition approach is employed to solve the characteristic of sensor saturation. The scaled small gain (SSG) theorem is extended to the stochastic systems, which is employed to handle with the time-varying delay by transforming the original system into the form of an interconnected system consisting of two subsys…

Comparative Study of Different Methods for the Prediction of Drug–Polymer Solubility

2015

In this study, a comparison of different methods to predict drug-polymer solubility was carried out on binary systems consisting of five model drugs (paracetamol, chloramphenicol, celecoxib, indomethacin, and felodipine) and polyvinylpyrrolidone/vinyl acetate copolymers (PVP/VA) of different monomer weight ratios. The drug-polymer solubility at 25 °C was predicted using the Flory-Huggins model, from data obtained at elevated temperature using thermal analysis methods based on the recrystallization of a supersaturated amorphous solid dispersion and two variations of the melting point depression method. These predictions were compared with the solubility in the low molecular weight liquid ana…

Generation of CO2-rich melts during basalt magma ascent and degassing

2013

International audience; To test mechanisms of basaltic ma gma degassing, continuous decompressions of volatile-bearing (2.7-3.8 wt% H2O, 600-1300 ppm CO2) Stromboli melts were performed from 250-200 to 50-25 MPa at 1180-1140°C. Ascent rates were varied from 0.25 to ~ 1.5 m/s. Glasses after decompression show a wide range of textures, from totally bubble-free to bubble-rich, the latter with bubble number densities from 104 to 106/cm3, similar to Stromboli pumices. Vesicularities range from 0 to ~ 20 vol%. Final melt H2O concentrations are homogeneous and always close to solubilities. In contrast, the rate of vesiculation controls the final melt CO2 concentration. High vesicularity charges ha…

Forecasting Etna eruptions by real-time observation of volcanic gas composition

2007

It is generally accepted, but not experimentally proven, that a quantitative prediction of volcanic eruptions is possible from the evaluation of volcanic gas data. By discussing the results of two years of real-time observation of H2O, CO2, and SO2 in volcanic gases from Mount Etna volcano, we unambiguously demonstrate that increasing CO2/SO2 ratios can allow detection of the pre-eruptive degassing of rising magmas. Quantitative modeling by the use of a saturation model allows us to relate the pre-eruptive increases of the CO2/SO2 ratio to the refilling of Etna's shallow conduits with CO2-rich deep-reservoir magmas, leading to pressurization and triggering of eruption. The advent of real-ti…

Effect of pH and nitrite concentration on nitrite oxidation rate

2011

The effect of pH and nitrite concentration on the activity of the nitrite oxidizing bacteria (NOB) in an activated sludge reactor has been determined by means of laboratory batch experiments based on respirometric techniques. The bacterial activity was measured at different pH and at different total nitrite concentrations (TNO 2). The experimental results showed that the nitrite oxidation rate (NOR) depends on the TNO 2 concentration independently of the free nitrous acid (FNA) concentration, so FNA cannot be considered as the real substrate for NOB. NOB were strongly affected by low pH values (no activity was detected at pH 6.5) but no inhibition was observed at high pH values (activity wa…

Structure of longitudinal chromomagnetic fields in high energy collisions

2014

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial fields correspond to a color field condensate exhibiting domain-like structure over distance scales of order the saturation scale. At later times universal scaling emerges at large distances for all ensembles, with a nontrivial critical exponent. Finally, we compare the results for the Wilson loop to the two-point correlator of magnetic fields.

Two relaxation times and thermal nonlinear waves along wires with lateral heat exchange

2021

Abstract We propose a model for studying several nonlinear waves for heat transport along a cylindrical system with lateral non-linear heat transfer to the environment. We consider relaxational equations, each with its own relaxation time, for longitudinal heat transfer and for lateral heat transfer across the wall. We consider two kinds of nonlinear lateral heat transport: radiative heat transport, and flux-limited heat transport. This work generalizes our previous studies in which the relaxation time for the lateral heat transfer was considered equal to that of the longitudinal heat flux. We explore the influence of both relaxation times on the propagation speed of linear and nonlinear wa…