A framework for determining improved placement of current energy converters subject to environmental constraints

A modelling framework identifies deployment locations for current-energy-capture devices that maximise power output while minimising potential environmental impacts. The framework, based on the Environmental Fluid Dynamics Code, can incorporate site-specific environmental constraints. Over a 29-day period, energy outputs from three array layouts were estimated for: (1) the preliminary configuration (baseline), (2) an updated configuration that accounted for environmental constraints, (3) and an improved configuration subject to no environmental constraints. Of these layouts, array placement that did not consider environmental constraints extracted the most energy from flow (4.38?MW-hr/day), 19% higher than output from the baseline configuration (3.69?MW-hr/day). Array placement that considered environmental constraints removed 4.27?MW-hr/day of energy (16% more than baseline). This analysis framework accounts for bathymetry and flow-pattern variations that typical experimental studies cannot, demonstrating that it is a valuable tool for identifying improved array layouts for field deployments.     

Comparison of 0.46% calcium diets with and without added anions with a 0.7% calcium anionic diet as a means to reduce periparturient hypocalcemia

Most studies demonstrating that diets with low dietary cation-anion difference (DCAD) reduce hypocalcemia in cows add enough anions to the diet to reduce urine pH below 7.0. One objective of these experiments was to determine whether there is any benefit to periparturient plasma Ca concentration if diet anion addition results in a lesser degree of acidification of the cow and urine pH does not go below 7.0. Another method for reducing hypocalcemia involves feeding a prepartal diet that is Ca deficient. This places the cow in negative Ca balance before calving, stimulating parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D secretion before calving and thus promoting Ca homeostasis at calving. As practiced in the field, low-Ca diets are often about 0.5% Ca. Our second objective was to determine whether a 0.46% Ca diet would be sufficiently low in Ca to stimulate PTH secretion before calving. A meta-analysis of the literature suggests that a 0.5% Ca, low-DCAD diet will reduce hypocalcemia better than a 0.7% Ca diet. A third objective was to compare periparturient plasma Ca in cows fed 0.46 or 0.72% Ca diets with similar DCAD. In experiment 1, anions (primarily chloride) or anions plus Ca were added to a 1.4% K basal diet to create the following diets: 0.46% Ca and +167 mEq/kg of DCAD, 0.46% Ca and ?13 mEq/kg of DCAD, and 0.72% Ca and ?17 mEq/kg of DCAD. In experiment 2, the same amounts of anion were added to a 2.05% K basal diet to create the following diets: 0.46% Ca and +327 mEq/kg of DCAD, 0.46% Ca and +146 mEq/kg of DCAD, and 0.72% Ca and +140 mEq/kg of DCAD. In experiment 1, cows fed the diet with 0.46% Ca and +167 mEq/kg of DCAD had significantly lower plasma Ca concentration after calving than cows fed the 0.46 or 0.72% Ca diets with anions. Periparturient plasma Ca concentrations did not differ in cows fed the low-DCAD diets with 0.46 or 0.72% Ca. Urine pH was reduced from 8.27 in the diet with 0.46% Ca and +167 mEq/kg of DCAD to 7.07 and 7.41 in the 0.46 and 0.72% Ca anion diets, respectively. Precalving plasma PTH and 1,25-dihydroxyvitamin D concentrations were similar in cows fed the 0.46% Ca diets and the 0.72% Ca diets, suggesting that the 0.46% Ca diets were not low enough in Ca to place the cow in negative Ca balance before calving. In experiment 2, adding the anion supplements to a 2.05% K diet did not reduce urine pH below 8.0. Periparturient plasma Ca concentrations did not differ in cows in any group in experiment 2. Precalving diets that are 0.46% Ca fed ad libitum are too high in Ca to stimulate Ca homeostasis before calving. Adding anions to a diet can benefit periparturient cow plasma Ca concentration, but only if it alters acid–base status enough to reduce urine pH below 7.5.     

Biodegradation of Wool by Bacteria and Fungi and Enhancement of Wool Quality by Biosurfactant Washing

Biodegradation of Ryeland and Shetland wool by Bacillus subtilis W3 and Streptomyces albidoflavus were investigated. The effect of treating raw wool with Rhamnolipid was also studied. It is shown that the wool surface morphology is improved with effective displacement of surface contaminants revealing a smooth outer cuticle layer after just 2 days. These results have important practical implications for the establishment of a quick and easy biodegradable process for wool scouring finishing in textile industry or for the pre-treatment of keratinous waste materials before degradation by bacteria or fungi. This methodology provides an environmentally friendly alternative to conventional chemical pre-treatments.     

openLAB – Eine Forschungsbrücke zur Entwicklung eines digitalen Brückenzwillings

openLAB – A research bridge for developing a digital twin of bridges Within the IDA-KI project, a research bridge (openLAB) is being built and loaded up to the level of severe damage. This will be accompanied by extensive measurements and investigations, thus creating a unique database for the validation of damage detection and evaluation methods under real environmental conditions using a large-scale model. This article presents the project idea, the research bridge currently under construction, and the monitoring system installed at the bridge. The methods implemented for automated data analysis and fault detection in the monitoring data are presented and validated through load tests in the openLAB. First measurements recorded during the production process of the precast girders of the research bridge underline the potential of distributed fiber optic sensors for a monitoring from day one. The information gained from the construction and operation of the bridge is provided in a digital model. The conceptualization of the so-called “as maintained“ model and the data management will be presented.     

Electrospinning: A Simple and Versatile Technique for Producing Ceramic Nanofibers and Nanotubes

Electrospinning is a remarkably simple method for generating nanofibers of polymers. When combined with conventional sol–gel processing, it provides a versatile technique for producing ceramic nanofibers with either a solid, porous, or hollow structure. This article presents a brief overview of recent progress in preparation of ceramic nanofibers by electrospinning, with a focus on an introduction to experimental procedures and analysis of several technical issues that are vital for a successful electrospinning experiment. We also highlight the unique capabilities of this technique in processing ceramic materials into nanostructures, and illustrate some potential applications of these nanostructures.     

Enzyme-based additives for paints and coatings

Active enzymes and other active biomolecules sequestered in paints and coatings have the potential to provide one of the more unique surface coatings yet identified. We report here the design and characterization of biological additives for latex coatings which impart catalytic detoxification or biodefensive capabilities to surfaces. The concept has been verified by the application of catalytic surfaces in the remediation of organophosphorus (OP) compounds, which include many of the commonly used pesticides as well as the most dangerous chemical warfare agents. The strategy for manufacture of these biocatalytic coatings involves the coupling of the power of biology with off-the-shelf, environmentally friendly paints. In this study, the entrapment of the biocatalyst in a latex coating is verified by analysis of the catalytic parameters for the enzyme in the coating. An estimation of the coating's operational and storage stability is also provided. Given the knowledge of the stability and activity of native and modified organophosphorus hydrolase (OPH, EC 3.1.8.1), the initial model system in the development of catalytic coatings is the OPH-catalyzed hydrolysis of paraoxon, demeton-S and diisopropylfluorophosphate, as well as neurotoxic chemical warfare agents. Success with these enzyme-substrate pairs will be used as the base for the incorporation of other biocatalysts into films and coatings.     

Calibration of liquid crystal ultrafast pulse shaper with common-path spectral interferometry and application to coherent control with a covariance matrix adaptation evolutionary strategy

An ultrafast pulse shaper for coherent control applications is described, complete with a simple, reliable calibration technique and an advanced learning control algorithm. The calibration technique makes use of a common-path interferometer, producing less noisy measurements than a conventional Mach-Zehnder interferometer. A covariance matrix adaptation evolutionary strategy (ES) is demonstrated to perform better than a traditional ES for high-dimensional search landscapes.     

Lokale Lasteintragung über Bolzenverbindungen in dünne Bauteile aus textilbewehrtem Beton

Introduction of Local Loads Via Bolted Joints Into Thin Components Made of Textile Reinforced Concrete Load introduction over rod-shaped joints is particularly known from steel- and wood constructions. It is an easy method to join slab- and disc-like components. Within the paper at hand, the applicability of rod-shaped joints (bolts) for thin concrete-made components with textile reinforcement is examined. It will be clarified how a simple, solid and efficient load introduction into thin reinforced concrete elements can be realised. Therefore, the bearing behaviour of the joints depending on the parameters edge distance, reinforcement ratio or number of layers respectively, and orientation of the reinforcement was examined in 36 single tests in total. Due to the planned application, the examinations and tests are limited to a load application at disc level. Failure mechanisms and forms are described by using a struttie-model.