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Palaeoecological Interpretation of a Late Holocene Sediment Sequence from the Alpine Belt of the Southern Mongolian Altai Mountains
(2022-02-17)
The climate in the Altai Mountains is determined by two major climate systems whose dominance has varied over time, leading to significant spatio-temporal changes in temperature and precipitation during the Holocene. This study aimed at the reconstruction of the local to regional moisture and temperature conditions in an alpine belt of the southern Mongolian Altai during the Late Holocene. It thereby contributes to a more comprehensive understanding of the region’s palaeoclimate in the Holocene. Our reconstruction ...
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Modeling of fiber-coupled confocal and interferometric confocal distance sensors
(2022-04-06)
Laser distance sensors are a widespread, fast and contactless approach for distance and surface topography measurements. Main characteristics of those sensors are given by resolution, measurement speed and sensor geometry. With decreasing sensor size, the alignment of the optical components in sensor setup becomes more challenging. The depth response of optical profilers is analyzed to obtain characteristic parameters and, thus, to value the alignment and the transfer behavior of those sensors. We present a novel ...
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Current Research and Challenges in Bitumen Emulsion Manufacturing and Its Properties
(2022-03-09)
The global increase of road infrastructure and its impact on the environment requires serious attention to develop sustainable and environmentally friendly road materials. One group of those materials is produced by using bitumen emulsion. However, there are still scientific and technical obstacles standing against its regular application. The bitumen emulsion formulation process and compositional optimization are subjected to a high number of degrees of freedom. Consequently, obtaining the desired product is mostly ...
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Environmental and Economic Performance of CO₂-Based Methanol Production Using Long-Distance Transport for H₂ in Combination with CO₂ Point Sources: A Case Study for Germany
(2022-03-29)
The use of CO₂-based hydrocarbons plays a crucial role in reducing the climate footprint for several industry sectors, such as the chemical industry. Recent studies showed that regions which are favorable for the production of CO₂-based hydrocarbons from an energy perspective often do not provide concentrated point sources for CO₂, which leads to an increased environmental impact due to the higher energy demand of direct air capture processes. Thus, producing H2 in regions with high renewable power potential and ...
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Lie algebra for rotational subsystems of a driven asymmetric top
(2022-05-11)
We present an analytical approach to construct the Lie algebra of finite-dimensional subsystems of the driven asymmetric top rotor. Each rotational level is degenerate due to the isotropy of space, and the degeneracy increases with rotational excitation. For a given rotational excitation, we determine the nested commutators between drift and drive Hamiltonians using a graph representation. We then generate the Lie algebra for subsystems with arbitrary rotational excitation using an inductive argument.
Aufsatz
Prediction of total carotenoids, color, and moisture content of carrot slices during hot air drying using non-invasive hyperspectral imaging technique
(2022-02-04)
The objective of this paper was to evaluate the performance of Partial Least Square Regression (PLSR) model and to assess the statistical agreement between two different measurement techniques, that is, Vis–NIR hyperspectral imaging (HSI) and standard laboratory methods for quality evaluation of dried carrots throughout the hot-air drying process. Carrots at commercial maturity of 3.5 months after planting were harvested in two seasons (2017 and 2018) and dried in a convective hot air dryer at 50°C, 60°C, and 70°C. ...