We analyze how the process of dust settling affects the spectral energy distribution and optical appearance of protoplanetary disks. Using simple analytic estimates on the one hand, and detailed 1+1-D models on the other hand, we show that, while the time scale for settling down to the equator may exceed the life time of the disk, it takes much less time for even small grains of 0.1 μm to settl...

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This paper investigates denitrification of brines originating from membrane treatment of groundwater in an upflow sludge blanket (USB) reactor, a biofilm reactor without carrier. A simulated brine wastewater was prepared from tap water and contained a nitrate concentration of 125 mg/l as N and a total salt concentration of about 1%. In order to select for a suitable energy source for denitrific...

Sex ratio of adults (tertiary sex ratio, TSR) is a major feature of animal populations with consequences for their behaviour, genetic structure and viability. Spatial and temporal variation in TSR occurs within species but the mechanisms behind it are poorly understood. In this long-term study of a declining population of a socially monogamous, colonial, migratory bird, the barn swallow (Hirund...

The settling behavior and power consumption of dynamic opamps are considered. The dynamic opamp is compared with a class A opamp for di erent clock frequencies. A single pole model in a closed loop con guration is used to estimate slewing and settling behavior. SPICE simulation results agree with theoretical predictions. It is shown that for the same power consumption dynamic opamps settle much...

relates stream length (L, mi) to drainage-basin area (A, mi). In CG-6 (“Solving Problems,” May 1999), Stokes' Law was used to find the travel time for a dead foraminifer to settle to the abyssal plain. This equation, which relates settling velocity (v) of a small, spherical particle to the densities of the settling particle and fluid (ρs and ρf, respectively), the viscosity of the fluid (μ), an...

The settling dynamics of spherical and elliptical particles in a viscous Newtonian fluid are investigated numerically using a finite difference technique. The terminal velocity for spherical particles is calculated for different system sizes and the extrapolated value for an infinite system size is compared to the Oseen approximation. Special attention is given to the settling and tumbling moti...

1. Survey 2. Settling Chambers 2.1. Description of Settling Chambers 2.2. Handling of settled dust 3. Cyclone Separators 3.1. Operating Principle 3.2. Efficiency of Cyclone Separators 3.3. Applications 4. Mechanical centrifugal separators 5. Brownian Movement 6. Dry Atmospheric Deposition 6.1. Survey 6.2. Influence of Particle Dimensions 6.2.1. Coarse Particles 6.2.2. The finest Particles 6.2.3...

Pharmaceutical industry often generates highly toxic wastewater and sludge depending upon the used manufacturing process and season. The high BOD to COD ratio of this particular wastewater makes biological treatment difficult. Hence chemical treatment proves to be a useful option. Fenton’s reagent is used in the treatment of pharmaceutical industry wastewater in this study. The ferrous and hydr...

The effects of the cationic surfactant (cationic cetyl trimethyl ammonium bromide, CTAB) on the improvement of the sludge dewaterability using the cationic flocculant (cationic polyacrylamide, CPAM) were analyzed. Residual turbidity of supernatant, dry solid (DS) content, extracellular polymeric substances (EPS), specific resistance to filtration (SRF), zeta potential, floc size, and settling r...