15 research outputs found
739 observed NEAs and new 2-4m survey statistics within the EURONEAR network
We report follow-up observations of 477 program Near-Earth Asteroids (NEAs)
using nine telescopes of the EURONEAR network having apertures between 0.3 and
4.2 m. Adding these NEAs to our previous results we now count 739 program NEAs
followed-up by the EURONEAR network since 2006. The targets were selected using
EURONEAR planning tools focusing on high priority objects. Analyzing the
resulting orbital improvements suggests astrometric follow-up is most important
days to weeks after discovery, with recovery at a new opposition also valuable.
Additionally we observed 40 survey fields spanning three nights covering 11 sq.
degrees near opposition, using the Wide Field Camera on the 2.5m Isaac Newton
Telescope (INT), resulting in 104 discovered main belt asteroids (MBAs) and
another 626 unknown one-night objects. These fields, plus program NEA fields
from the INT and from the wide field MOSAIC II camera on the Blanco 4m
telescope, generated around 12,000 observations of 2,000 minor planets (mostly
MBAs) observed in 34 square degrees. We identify Near Earth Object (NEO)
candidates among the unknown (single night) objects using three selection
criteria. Testing these criteria on the (known) program NEAs shows the best
selection methods are our epsilon-miu model which checks solar elongation and
sky motion and the MPC's NEO rating tool. Our new data show that on average 0.5
NEO candidates per square degree should be observable in a 2m-class survey (in
agreement with past results), while an average of 2.7 NEO candidates per square
degree should be observable in a 4m-class survey (although our Blanco
statistics were affected by clouds). At opposition just over 100 MBAs (1.6
unknown to every 1 known) per square degree are detectable to R=22 in a 2m
survey based on the INT data, while our two best ecliptic Blanco fields away
from opposition lead to 135 MBAs (2 unknown to every 1 known) to R=23.Comment: Published in Planetary and Space Sciences (Sep 2013
Entfeuchtung von Hochofenwind bei der Ferromanganerzeugung Schlussbericht. Abschlussdatum: Maerz 1985
SIGLETIB: RN 2598 (86-080) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Konstruktion des Kryosammlers Typ V zur Entnahme von Luftproben in der Stratosphaere
Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Molecular dynamics simulations of surfactant adsorption at oil/water interface under shear flow
Surfactants are extensively used in many chemical products to improve their stability, appearance, texture, and rheology. Precise control of the emulsion droplet size distribution, which depends on the characteristics of the surfactant used, is important for target-oriented product design. A complete understanding of the structures and dynamics of emulsion droplets at the reactor level requires coupling of two mesoscale physical constraints, that at the interfacial level, i.e., smaller than a single droplet (Mesoscale-1), and that at the device level, i.e., larger than a single droplet (Mesoscale-2). In this work, the structures and adsorption kinetics of Mesoscale-1 surfactant molecules were studied via coarse-grained molecular dynamics. A non-equilibrium model that could introduce stable shear flow into the simulation box was used to investigate the interfacial structures at the droplet interface under different shear rates. The configurations of the surfactant molecules and adsorption amounts were compared with those obtained without flow. The adsorption kinetics for different shear rates were compared to determine the effects of hydrodynamic interactions. The dominant mechanisms governing the dynamic structures can thus be summarized as maximization of the adsorption density at the interface and minimization of flow resistance in the bulk phase (water and/or oil molecules). A scheme for coupling between Mesoscale-1 and Mesoscale-2 is proposed. This method is promising for the incorporation of interfacial structure effects into the hydrodynamics at the reactor device level for the manipulation of chemical products. (C) 2019 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved