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Industrial facilities must be thoroughly designed to withstand seismic
actions as they exhibit an increased loss potential due to the possibly wideranging
damage consequences and the valuable process engineering equipment.
Past earthquakes showed the social and political consequences of seismic damage
to industrial facilities and sensitized the population and politicians worldwide
for the possible hazard emanating from industrial facilities. However, a holistic
approach for the seismic design of industrial facilities can presently neither be
found in national nor in international standards. The introduction of EN 1998-4
of the new generation of Eurocode 8 will improve the normative situation with
specific seismic design rules for silos, tanks and pipelines and secondary process
components. The article presents essential aspects of the seismic design of
industrial facilities based on the new generation of Eurocode 8 using the example
of tank structures and secondary process components. The interaction effects of
the process components with the primary structure are illustrated by means of
the experimental results of a shaking table test of a three story moment resisting
steel frame with different process components. Finally, an integrated approach of
digital plant models based on building information modelling (BIM) and structural
health monitoring (SHM) is presented, which provides not only a reliable
decision-making basis for operation, maintenance and repair but also an excellent
tool for rapid assessment of seismic damage.
A 2-dimensional detector system for high resolution thyroid I-131 scintigraphy was developed. It has a sensitive area of 4 cm×4 cm and consists of a lead-collimator and an array of 10×10 EGO crystals combined with a position sensitive photomultiplier. The spatial resolution and the sensitivity of the detector has been measured and compared to two commercially available gamma-cameras. Furthermore first patient measurements have been carried out
Thermal management in E-carsharing vehicles - preconditioning concepts of passenger compartments
(2015)
The issue of thermal management in electric vehicles includes the topics of drivetrain cooling and heating, interior temperature, vehicle body conditioning and safety. In addition to the need to ensure optimal thermal operating conditions of the drivetrain components (drive motor, battery and electrical components), thermal comfort must be provided for the passengers. Thermal comfort is defined as the feeling which expresses the satisfaction of the passengers with the ambient conditions in the compartment. The influencing factors on thermal comfort are the temperature and humidity as well as the speed of the indoor air and the clothing and the activity of the passengers, in addition to the thermal radiation and the temperatures of the interior surfaces. The generation and the maintenance of free visibility (ice- and moisture-free windows) count just as important as on-demand heating and cooling of the entire vehicle. A Carsharing climate concept of the innovative ec2go vehicle stipulates and allows for only seating areas used by passengers to be thermally conditioned in a close-to-body manner. To enable this, a particular feature has been added to the preconditioning of the Carsharing electric vehicle during the electric charging phase at the parking station.
The investigation of the possibility to determine various characteristics of powder heparin (n = 115) was carried out with infrared spectroscopy. The evaluation of heparin samples included several parameters such as purity grade, distributing company, animal source as well as heparin species (i.e. Na-heparin, Ca-heparin, and heparinoids). Multivariate analysis using principal component analysis (PCA), soft independent modelling of class analogy (SIMCA), and partial least squares – discriminant analysis (PLS-DA) were applied for the modelling of spectral data. Different pre-processing methods were applied to IR spectral data; multiplicative scatter correction (MSC) was chosen as the most relevant.
Obtained results were confirmed by nuclear magnetic resonance (NMR) spectroscopy. Good predictive ability of this approach demonstrates the potential of IR spectroscopy and chemometrics for screening of heparin quality. This approach, however, is designed as a screening tool and is not considered as a replacement for either of the methods required by USP and FDA.
Geologisch-geotechnischer Planungsprozess von Tunnelbauten mit Schwerpunkt tiefliegender Tunnel
(2014)
The molecular weight properties of lignins are one of the key elements that need to be analyzed for a successful industrial application of these promising biopolymers. In this study, the use of 1H NMR as well as diffusion-ordered spectroscopy (DOSY NMR), combined with multivariate regression methods, was investigated for the determination of the molecular weight (Mw and Mn) and the polydispersity of organosolv lignins (n = 53, Miscanthus x giganteus, Paulownia tomentosa, and Silphium perfoliatum). The suitability of the models was demonstrated by cross validation (CV) as well as by an independent validation set of samples from different biomass origins (beech wood and wheat straw). CV errors of ca. 7–9 and 14–16% were achieved for all parameters with the models from the 1H NMR spectra and the DOSY NMR data, respectively. The prediction errors for the validation samples were in a similar range for the partial least squares model from the 1H NMR data and for a multiple linear regression using the DOSY NMR data. The results indicate the usefulness of NMR measurements combined with multivariate regression methods as a potential alternative to more time-consuming methods such as gel permeation chromatography.
Lignin is a promising renewable biopolymer being investigated worldwide as an environmentally benign substitute of fossil-based aromatic compounds, e.g. for the use as an excipient with antioxidant and antimicrobial properties in drug delivery or even as active compound. For its successful implementation into process streams, a quick, easy, and reliable method is needed for its molecular weight determination. Here we present a method using 1H spectra of benchtop as well as conventional NMR systems in combination with multivariate data analysis, to determine lignin’s molecular weight (Mw and Mn) and polydispersity index (PDI). A set of 36 organosolv lignin samples (from Miscanthus x giganteus, Paulownia tomentosa and Silphium perfoliatum) was used for the calibration and cross validation, and 17 samples were used as external validation set. Validation errors between 5.6% and 12.9% were achieved for all parameters on all NMR devices (43, 60, 500 and 600 MHz). Surprisingly, no significant difference in the performance of the benchtop and high-field devices was found. This facilitates the application of this method for determining lignin’s molecular weight in an industrial environment because of the low maintenance expenditure, small footprint, ruggedness, and low cost of permanent magnet benchtop NMR systems.
Application of the optical flow method to velocity determination in hydraulic structure models
(2016)
As with most high-velocity free-surface flows, stepped spillway flows become self-aerated when the drop height exceeds a critical value. Due to the step-induced macro-roughness, the flow field becomes more turbulent than on a similar smooth-invert chute. For this reason, cascades are oftentimes used as re-aeration structures in wastewater treatment. However, for stepped spillways as flood release structures downstream of deoxygenated reservoirs, gas transfer is also of crucial significance to meet ecological requirements. Prediction of mass transfer velocities becomes challenging, as the flow regime differs from typical previously studied flow conditions. In this paper, detailed air-water flow measurements are conducted on stepped spillway models with different geometry, with the aim to estimate the specific air-water interface. Re-aeration performances are determined by applying the absorption method. In contrast to earlier studies, the aerated water body is considered a continuous mixture up to a level where 75% air concentration is reached. Above this level, a homogenous surface wave field is considered, which is found to significantly affect the total air-water interface available for mass transfer. Geometrical characteristics of these surface waves are obtained from high-speed camera investigations. The results show that both the mean air concentration and the mean flow velocity have influence on the mass transfer. Finally, an empirical relationship for the mass transfer on stepped spillway models is proposed.
Optical flow estimation is known from Computer Vision where it is used to determine obstacle movements through a sequence of images following an assumption of brightness conservation. This paper presents the first study on application of the optical flow method to aerated stepped spillway flows. For this purpose, the flow is captured with a high-speed camera and illuminated with a synchronized LED light source. The flow velocities, obtained using a basic Horn–Schunck method for estimation of the optical flow coupled with an image pyramid multi-resolution approach for image filtering, compare well with data from intrusive conductivity probe measurements. Application of the Horn–Schunck method yields densely populated flow field data sets with velocity information for every pixel. It is found that the image pyramid approach has the most significant effect on the accuracy compared to other image processing techniques. However, the final results show some dependency on the pixel intensity distribution, with better accuracy found for grey values between 100 and 150.
Optimization of the reaeration potential on embankment stepped spillways in skimming flow regime
(2008)
Optimierung des potentiellen Sauerstoffeintrags auf Treppenschussrinnen mit gemäßigter Neigung
(2009)
Sensitivity of phase detection techniques in aerated chute flows to hydraulic design parameters
(2012)
Hydraulic modeling is the classical approach to investigate and describe complex fluid motion. Many empirical formulas in the literature used for the hydraulic design of river training measures and structures have been developed using experimental data from the laboratory. Although computer capacities have increased to a high level which allows to run complex numerical simulations on standard workstation nowadays, non-standard design of structures may still raise the need to perform physical model investigations. These investigations deliver insight into details of flow patterns and the effect of varying boundary conditions. Data from hydraulic model tests may be used for calibration of numerical models as well. As the field of hydraulic modeling is very complex, this chapter intends to give a short overview on capacities and limits of hydraulic modeling in regard to river flows and hydraulic structures only. The reader shall get a first idea of modeling principles and basic considerations. More detailed information can be found in the references.
Hochtemperaturtechnik
(1990)
Hochtemperaturtechnik. Interne Arbeitssitzung des GVC-Fachausschusses 'Hochtemperaturtechnik'
(1989)
In Zeiten von Schnelllebigkeit ändern immer mehr Menschen bewusst ihren Umgang mit alltäglichen Dingen. Was dabei häufig in den Hintergrund rückt, ist das Thema "bewusste Kleidung". Beeinflusst durch sogenannte Fast-Fashion-Modeketten und Social Media leben wir in einer regelrechten Wegwerfgesellschaft. „Entschleunigen“ beschäftigt sich mit den Schattenseiten der Modeindustrie, zeigt aber ebenso (neue) Wege auf, die auf eine bessere Zukunft für uns und unsere Umwelt hoffen lassen. Aufgeteilt in zwei Kapitel gibt „Entschleunigen“ einen Einblick in den ökologischen und sozialen Fußabdruck der Modeindustrie und stellt zum anderen die Gegenseite vor, bei der Wert auf faire Produktion und Nachhaltigkeit gelegt wird. Das Buch „Entschleunigen“ soll über die Missstände in der Textilbranche informieren, jedoch im Umkehrschluss dazu motivieren, diese mit einfachen Mitteln zu verbessern.
Tribological performance of biodegradable lubricants under different surface roughness of tools
(2019)
Praxistransfer in der tertiären Bildungsforschung: Modelle, Gelingensbedingungen und Nachhaltigkeit
(2019)
Dieses Jahr werden allein in Deutschland ca. 47 Millionen Sneaker verkauft. Die Sneakerbranche boomt und ist nicht mehr aufzuhalten. Was zu Beginn nur ein Sportschuh war, ist heute ein Lifestyleprodukt und auf dem Markt und im Alltag nicht mehr wegzudenken. Der Hype um den neuesten Sneaker ist unglaublich groß und das Bedürfnis nach dem Präsentieren und dem zur Schau stellen wächst.
Mit der float collection gelingt es, den Verkaufs- und Ausstellungsraum ganz individuell und vielseitig zu gestalten. Das Besondere hier ist, dass die Schuhe sich visuell schwebend in den Regalen etablieren und so von allen Seiten betrachtet werden können. Das Konstrukt ist modular und bringt durch das Material Metall eine lange Produktlebensdauer mit sich.
So bringst du nicht nur die Sneaker, sondern auch die Herzen deiner Kunden zum Schweben.
Let the shoes float.
Prinzip und Anwendung der akustischen Gastemperaturmeßtechnik / Deuster, M. ; Brüssermann, Klaus
(1994)
By developing innovative solutions to social and environmental problems, sustainable ventures carry greatpotential. Entrepreneurship which focuses especially on new venture creation can be developed through education anduniversities, in particular, are called upon to provide an impetus for social change. But social innovations are associatedwith certain hurdles, which are related to the multi-dimensionality, i.e. the tension between creating social,environmental and economic value and dealing with a multiplicity of stakeholders. The already complex field ofentrepreneurship education has to face these challenges. This paper, therefore, aims to identify starting points for theintegration of sustainability into entrepreneurship education. To pursue this goal experiences from three differentproject initiatives between the partner universities: Lapland University of Applied Sciences, FH Aachen University ofApplied Sciences and Turiba University are reflected and findings are systematically condensed into recommendationsfor education on sustainable entrepreneurship.
Light-addressable potentiometric sensors (LAPS) consisting of a p-Si-SiO2 and p-Si-SiO2-Au structure, respectively, have been tested for a label-free electrical detection of DNA (deoxyribonucleic acid) hybridization. Three different strategies for immobilizing single-stranded probe DNA (ssDNA) molecules on a LAPS surface have been studied and compared: (a) immobilization of thiol-modified ssDNA on the patterned Au surface via gold-thiol bond, (b) covalent immobilization of amino-modified ssDNA onto the SiO2 surface functionalized with 3-aminopropyltriethoxysilane and (c) layer-by-layer adsorption of negatively charged ssDNA on a positively charged weak polyelectrolyte layer of poly(allylamine hydrochloride).
Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte–insulator–semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance–voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event.
Capacitive field-effect electrolyte-insulator-semiconductor sensors consisting of an Al-p-Si-SiO2 structure have been used for the electrical detection of unlabelled single- and double-stranded DNA (dsDNA) molecules by their intrinsic charge. A simple functionalization protocol based on the layer-by-layer (LbL) technique was used to prepare a weak polyelectrolyte/probe-DNA bilayer, followed by the hybridization with complementary target DNA molecules. Due to the flat orientation of the LbL-adsorbed DNA molecules, a high sensor signal has been achieved. In addition, direct label-free detection of in-solution hybridized dsDNA molecules has been studied.
In this study, polyelectrolyte-modified field-effect-based electrolyte-insulator-semiconductor (EIS) devices have been used for the label-free electrical detection of double-stranded deoxyribonucleic acid (dsDNA)molecules. The sensor-chip functionalization with a positively charged polyelectrolyte layer provides the possibility of direct adsorptive binding of negatively charged target DNA oligonucleotides onto theSiO2-chip surface.EIS sensors can be utilized as a tool to detect surface-charge changes; the electrostatic adsorption of oligonucleotides onto the polyelectrolyte layer leads to a measureable surface-potential change. Signals of 39mV have been recorded after the incubation with the oligonucleotide solution. Besides the electrochemical experiments, the successful adsorption of dsDNA onto the polyelectrolyte layer has been verified via fluorescence microscopy. The presented results demonstrate that the signal recording of EISchips, which are modified with a polyelectrolyte layer, canbe used as a favorable approach for a fast, cheap and simple detection method for dsDNA.
Field-effect-based electrolyte-insulator-semiconductor (EIS) sensors were modified with a bilayer of positively charged weak polyelectrolyte (poly(allylamine hydrochloride) (PAH)) and probe single-stranded DNA (ssDNA) and are used for the detection of complementary single-stranded target DNA (cDNA) in different test solutions. The sensing mechanism is based on the detection of the intrinsic molecular charge of target cDNA molecules after the hybridization event between cDNA and immobilized probe ssDNA. The test solutions contain synthetic cDNA oligonucleotides (with a sequence of tuberculosis mycobacteria genome) or PCR-amplified DNA (which origins from a template DNA strand that has been extracted from Mycobacterium avium paratuberculosis-spiked human sputum samples), respectively. Sensor responses up to 41 mV have been measured for the test solutions with DNA, while only small signals of ∼5 mV were detected for solutions without DNA. The lower detection limit of the EIS sensors was ∼0.3 nM, and the sensitivity was ∼7.2 mV/decade. Fluorescence experiments using SybrGreen I fluorescence dye support the electrochemical results.