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An alternative to field retting: Fibrous materials based on wet preserved hemp for the manufacture of composites
A process developed at the Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB) for the supply and processing of wet-preserved fiber plants opens up new potential uses for such resources. The processing of industrial hemp into fiber materials and products thereof is undergoing experimental research along the value-added chain from the growing process through to the manufacturing of product samples. The process comprises the direct harvesting of the field-fresh hemp and the subsequent anaerobic storage of the entire plant material. Thus, process risk due to unfavorable weather conditions is prevented in contrast to common dew retting procedures. The effects of the anaerobic storage processes on the properties of the bast part of the plant material are comparable to the results of common retting procedures. Harvest storage, as well as further mechanical processing, leads to different geometrical properties compared to the bast fibers resulting from traditional post harvesting treatment and decortication. The fiber raw material obtained in this way is well suited to the production of fiberboards and the reinforcement of polymer or mineral bonded composites. The objective of this paper is to present recent research results on final products extended by a comprehensive overview of the whole supply chain in order to enable further understanding of the result influencing aspects of prior process steps
Determining the boundaries of the auroral oval from CHAMP field-aligned current signatures – Part 1
Comparing plasma bubble occurrence rates at CHAMP and GRACE altitudes during high and low solar activity
Based on the multi-year data base (2001–2009) of CHAMP Planar Langmuir Probe
(PLP) data and GRACE K-Band Ranging (KBR1B) data, typical features of
ionospheric plasma irregularities are studied at the altitudes of CHAMP
(300–400 km) and GRACE (~500 km). The phenomena we are focusing on are
the equatorial plasma bubbles (EPBs). Similar seasonal/longitudinal (S/L)
distributions of EPB have been found at both CHAMP and GRACE altitudes
during solar active and quiet years. Peak EPB occurrence rates, defined as
number of events within an S/L bin divided by the number of passes over that
bin, decrease from the high and moderate solar flux period (2001–2005) to
the low solar flux period (2005–2009) from 80% to 60% and 60% to
40% at CHAMP and GRACE altitudes, respectively. On average the occurrence
rate increases linearly with solar flux at about the same rate at CHAMP and
GRACE. For high flux levels (P10.7>200) non-linear increases are observed
at GRACE. The occurrence rate increases rapidly after 19:00 local time (LT)
during high solar flux periods. Around solar minimum rates increase more
gently and peak around 22:00 LT. The highest occurrence rates are encountered
at latitudes around 10° north and south of the dip equator. Results
from the two altitudes support the notion that EPBs form regions of depleted
plasma along geomagnetic fluxtubes. It is shown for the first time that in
regions of high occurrence rates EPBs are associated with fluxtubes reaching
greater apex heights than those in regions of low rates
A statistical investigation of traveling convection vortices observed by the west coast Greenland magnetometer chain
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95409/1/jgra16162.pd
Field-aligned current associated with low-latitude plasma blobs as observed by the CHAMP satellite
Here we give two examples of low-latitude plasma blobs accompanied by linearly polarized perpendicular magnetic deflections which imply that associated field-aligned currents (FACs) have a 2-D sheet structure located at the blob walls. The estimated FAC density is of the order of 0.1 &mu;A/m<sup>2</sup>. The direction of magnetic deflections points westward of the magnetic meridian and there is a linear correlation between perpendicular and parallel variations. All these properties are similar to those of equatorial plasma bubbles (EPBs). According to CHAMP observations from August 2000 to July 2004, blobs show except for these two good examples no clear signatures of 2-D FAC sheets at the walls. Generally, perpendicular magnetic deflections inside blobs are weaker than inside EPBs on average. Our results are consistent with existing theories: if a blob exists, (1) a significant part of EPB FAC will be closed through it, exhibiting similar perpendicular magnetic deflection inside EPBs and blobs, (2) the FAC closure through blobs leads to smaller perpendicular magnetic deflection at its poleward/downward side, and (3) superposition of different FAC elements might result in a complex magnetic signature around blobs
Gewichtszunahme von Karpfen in Kleinstbehältern, zugleich Beitrag zur Aufklärung des Raumfaktors
Magnetic signatures of ionospheric and magnetospheric current systems during geomagnetic quiet conditions - An overview
Estimating along-track plasma drift speed from electron density measurements by the three Swarm satellites
An empirical model of the thermospheric mass density derived from CHAMP satellite
In this study, we present an empirical model, named CH-Therm-2018, of the
thermospheric mass density derived from 9-year (from August 2000 to
July 2009) accelerometer measurements from the CHAllenging
Mini-satellite Payload (CHAMP)
satellite at altitudes from 460 to 310 km. The CHAMP dataset is divided into
two 5-year periods with 1-year overlap (from August 2000 to July 2005 and
from August 2004 to July 2009) to represent the high-to-moderate and
moderate-to-low solar activity conditions, respectively. The CH-Therm-2018
model describes the thermospheric density as a function of seven key
parameters, namely the height, solar flux index, season (day of year),
magnetic local time, geographic latitude and longitude, as well as magnetic
activity represented by the solar wind merging electric field. Predictions of
the CH-Therm-2018 model agree well with CHAMP observations (within 20 %)
and show different features of thermospheric mass density during the two
solar activity levels, e.g., the March–September equinox asymmetry and the
longitudinal wave pattern. From the analysis of satellite laser ranging (SLR)
observations of the ANDE-Pollux satellite during August–September 2009, we
estimate 6 h scaling factors of the thermospheric mass density provided by
our model and obtain the median value equal to 1.267±0.60. Subsequently,
we scale up our CH-Therm-2018 mass density predictions by a scale factor of
1.267. We further compare the CH-Therm-2018 predictions with the Naval
Research Laboratory Mass Spectrometer Incoherent Scatter Radar Extended
(NRLMSISE-00) model. The result shows that our model better predicts the
density evolution during the last solar minimum (2008–2009) than the
NRLMSISE-00 model.</p
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