•Experiments with a newly developed radial inflow cantilever turbine are presented.•The experimental results are compared to a classical axial impulse turbine.•Efficiency characteritics for full-load ...and part-load behaviour are shown.•The 12 kW turbines reach maximum efficiencies of more than 75%.•It proves that small turbines are efficient and reasonable expanders in small ORCs.
Electricity generation from waste heat by means of Organic Rankine Cycle is a promising method to increase the efficiency of industrial processes. However, due to special boundary conditions, such systems have to be robust, efficient in full load as well as in part load and scalable down to the power range of less than 15 kW. This study presents experimental results on the behaviour of two small-scale turbines, an axial impulse turbine and a radial cantilever turbine with a maximum power of about 12 kW. The turbine characteristics (isentropic efficiency and swallowing capacity) are given with respect to pressure ratio (ranging from 12 to 24) and rotational speed (ranging from 18,000 to 30,000 rotations per minute). For the axial turbine, a maximum isentropic efficiency of 73.4% has been reached in the ORC test bed. The maximum isentropic efficiency of the cantilever turbine is even higher and reaches 76.8%. The values are compared to volumetric expanders and it is shown that micro-turbines can compete even in the power range addressed in this study. As the turbine characteristics are given for full load and part load conditions, they can be implemented in simulation tools to allow for a more realistic calculation of ORCs with fluctuating heat sources.
Recently, molecular tumour boards (MTBs) have been integrated into the clinical routine. Since their benefit remains debated, we assessed MTB outcomes in the Comprehensive Cancer Center Ostbayern ...(CCCO) from 2019 to 2021.
In total, 251 patients were included. Targeted sequencing was performed with PCR MSI-evaluation and immunohistochemistry for PD-L1, Her2, and mismatch repair enzymes. 125 treatment recommendations were given (49.8%). High-recommendation rates were achieved for intrahepatic cholangiocarcinoma (20/30, 66.7%) and gastric adenocarcinoma (10/16, 62.5%) as opposed to colorectal cancer (9/36, 25.0%) and pancreatic cancer (3/18, 16.7%). MTB therapies were administered in 47 (18.7%) patients, while 53 (21.1%) received alternative treatment regimens. Thus 37.6% of recommended MTB therapies were implemented (47/125 recommendations). The clinical benefit rate (complete + partial + mixed response + stable disease) was 50.0% for MTB and 63.8% for alternative treatments. PFS2/1 ratios were 34.6% and 16.1%, respectively. Significantly improved PFS could be achieved for m1A-tier-evidence-based MTB therapies (median 6.30 months) compared to alternative treatments (median 2.83 months; P = 0.0278).
The CCCO MTB yielded a considerable recommendation rate, particularly in cholangiocarcinoma patients. The discrepancy between the low-recommendation rates in colorectal and pancreatic cancer suggests the necessity of a weighted prioritisation of entities. High-tier recommendations should be implemented predominantly.
The shift toward electric mobility in Germany is a major component of the German climate protection program. In this context, public charging is growing in importance, especially in high-density ...urban areas, which causes an additional load on the distribution grid. In order to evaluate this impact and prevent possible overloads, realistic models are required. Methods for implementing such models and their application in the context of grid load are research topics that are only minorly addressed in the literature. This paper aims to demonstrate the entire process chain from the selection of a modelling method to the implementation and application of the model within a case study. Applying a stochastic approach, charging points are modelled via probabilities to determine the start of charging, plug-in duration, and charged energy. Subsequently, load profiles are calculated, integrated into an energy system model and applied in order to analyze the effects of a high density of public charging points on the urban distribution grid. The case study highlights a possible application of the implemented probabilistic load profile model, but also reveals its limitations. The primary results of this paper are the identification and evaluation of relevant criteria for modelling the load profiles of public charging points as well as the demonstration of the model and its comparison to real charging processes. By publishing the determined probabilities and the model for calculating the charging load profiles, a comprehensive tool is provided.
Baryonic feedback effects lead to a suppression of the weak lensing angular power spectrum on small scales. The poorly constrained shape and amplitude of this suppression is an important source of ...uncertainties for upcoming cosmological weak lensing surveys such as Euclid or LSST. In this first paper in a series of two, we use simulations to build a Euclid-like tomographic mock data-set for the cosmic shear power spectrum and the corresponding covariance matrix, which are both corrected for baryonic effects following the baryonification method of 1. In addition, we develop an emulator to obtain fast predictions of the baryonic power suppression, allowing us to perform a likelihood inference analysis for a standard ΛCDM cosmology with both cosmological and astrophysical parameters. Our main findings are the following: (i) ignoring baryonic effects leads to a greater than 5σ bias on the cosmological parameters Ωm and σ8; (ii) restricting the analysis to the largest scales, that are mostly unaffected by baryons, makes the bias disappear, but results in a blow-up of the Ωm-σ8 contour area by more than a factor of 10; (iii) ignoring baryonic effects on the covariance matrix does not significantly affect cosmological parameter estimates; (iv) while the baryonic suppression is mildly cosmology dependent, this effect does not noticeably modify the posterior contours. Overall, we conclude that including baryonic uncertainties in terms of nuisance parameters results in unbiased and surprisingly tight constraints on cosmology.
Due to the various ORC applications, it is not expedient to design and build one standard turbogenerator. Therefore, authors developed a flexible “micro-turbine-generator-construction-kit ...(MTG-c-kit)” by means of which a customized turbogenerator can be made for any required power output between 1 and 200 kW, for a wide range of working fluids and boundary conditions – quickly, cost effectively and with high expander efficiency. The architecture and main features of this kit are briefly introduced.
However, more focus is put on the developed 1D turbine design tool. It allows to quickly design and optimize a single stage turbine for any fluid and boundary conditions. The implemented models are presented on two specific design examples - an axial impulse and a radial inflow cantilever turbine. Also, the experimental results of the two micro turbines designed and built according to this approach, are presented and discussed.
Focusing to further accelerate and cheapen the customized micro-turbogenerators for low temperature applications, we provide an outlook of possibilities of additive manufacturing methods like 3D printing of turbine nozzles and rotors. These new possibilities provide potential to improve the competiveness of small-scale ORC. A simple air turbine design with plastic and metal components has been manufactured and tested.
•Axial and radial impulse turbines were chosen as a basis of the 1–200 kWe MTG-c-kit.•The kit provides flexible, efficient and cost-effective design for ORC turbomachinery.•1D model for quick, yet accurate, design and performance prediction is presented.•3D printing brings potential for further customization and cost reduction.•Experimental verification is shown for two MM turbines and 3D printed air turbines.
Expectations on mesenchymal stem cell (MSC) treatment are high, especially in the fields of sepsis, transplant medicine, and autoimmune diseases. Various pre-clinical studies have been conducted with ...encouraging results, although the mechanisms of action behind the observed immunomodulatory capacity of mesenchymal stem cells have not been fully understood. Previous studies have demonstrated that the immunomodulatory effect of MSCs is communicated via MSC-secreted cytokines and has been proven to rely on the local microenvironment as some of the observed effects depend on a pre-treatment of MSCs with inflammatory cytokines. Nonetheless, recent findings indicate that the cytokine-mediated effects are only one part of the equation as apoptotic, metabolically inactivated, or even fragmented MSCs have been shown to possess an immunomodulatory potential as well. Both cytokine-dependent and cytokine-independent mechanisms suggest a key role for regulatory T cells and monocytes in the overall pattern, but the principle as to why viable and non-viable MSCs have similar immunomodulatory capacities remains elusive. Here we review the current knowledge on cellular and molecular mechanisms involved in MSC-mediated immunomodulation and focus on the viability of MSCs, as there is still uncertainty concerning the tumorigenic potential of living MSCs.
Micro turbines (<100 kWel) are commercially used as expansion machines in waste heat recovery (WHR) systems such as organic Rankine cycles (ORCs). These highly loaded turbines are generally designed ...for a specific parameter set, and their isentropic expansion efficiency significantly deteriorates when the mass flow rate of the WHR system deviates from the design point. However, in numerous industry processes that are potentially interesting for the implementation of a WHR process, the temperature, mass flow rate or both can fluctuate significantly, resulting in fluctuations in the WHR system as well. In such circumstances, the inlet pressure of the ORC turbine, and therefore the reversible cycle efficiency must be significantly reduced during these fluctuations. In this context, the authors developed an adaptive supersonic micro turbine for WHR applications. The variable geometry of the turbine nozzles enables an adjustment of the swallowing capacity in respect of the available mass flow rate in order to keep the upper cycle pressure constant. In this paper, an experimental test series of a WHR ORC test rig equipped with the developed adaptive supersonic micro turbine is analysed. The adaptive turbine is characterized concerning its off-design performance and the results are compared to a reference turbine with fixed geometry. To create a fair data basis for this comparison, a digital twin of the plant based on experimental data was built. In addition to the characterization of the turbine itself, the influence of the improved pressure ratio on the energy conversion chain of the entire ORC is analysed.
The deformation-induced processes by tensile loading of X5CrNi18-10 austenitic stainless steel in the temperature range of 77 K to 413 K (−196 °C to 140 °C) were investigated. The results were ...presented in the form of stress–temperature-transformation (STT) and strain–temperature-transformation (DTT) diagrams. The thermodynamic stability of the austenite with respect to the
ε
- and
α
′-martensite transformations was reflected in the STT and DTT diagrams. Furthermore, conclusions could be drawn from the transformation diagrams about the kinetics of stress- and strain-induced martensitic transformations. The diagrams laid foundations for the development of a new method of quantitative determination of strength and elongation contributions by means of induced and often overlapping deformation processes in the austenite. In this context, the plastic strains contributed by the glide and shearing of austenite were quantified and presented in connection with the
ε
and
α
′ TRansformation-Induced Plasticity effects. Each deformation process was shown to have made a contribution to the strength and ductility, with a magnitude proportional to its dominance. The summation of such contributions provided the tensile strength and the uniform elongation of the steel. In other words, tensile strength and uniform elongation could be derived from a rule of mixtures. The newly proposed method was capable of explaining the anomalous temperature dependence of uniform elongation in the alloy investigated.
Effects of baryons on weak lensing peak statistics Weiss, Andreas J.; Schneider, Aurel; Sgier, Raphael ...
Journal of cosmology and astroparticle physics,
10/2019, Letnik:
2019, Številka:
10
Journal Article
Recenzirano
Upcoming weak-lensing surveys have the potential to become leading cosmological probes provided all systematic effects are under control. Recently, the ejection of gas due to feedback energy from ...active galactic nuclei (AGN) has been identified as major source of uncertainty, challenging the success of future weak-lensing probes in terms of cosmology. In this paper we investigate the effects of baryons on the number of weak-lensing peaks in the convergence field. Our analysis is based on full-sky convergence maps constructed via light-cones from N-body simulations, and we rely on the baryonic correction model of 1 to model the baryonic effects on the density field. As a result we find that the baryonic effects strongly depend on the Gaussian smoothing applied to the convergence map. For a DES-like survey setup, a smoothing of θk≳8 arcmin is sufficient to keep the baryon signal below the expected statistical error. Smaller smoothing scales lead to a significant suppression of high peaks with / >2, while lower peaks are not affected. The situation is more severe for a Euclid-like setup, where a smoothing of θk≳16 arcmin is required to keep the baryonic suppression signal below the statistical error. Smaller smoothing scales require a full modelling of baryonic effects since both low and high peaks are strongly affected by baryonic feedback.
Abstract Detecting large-scale flux ropes (FRs) embedded in interplanetary coronal mass ejections (ICMEs) and assessing their geoeffectiveness are essential, since they can drive severe space ...weather. At 1 au, these FRs have an average duration of 1 day. Their most common magnetic features are large, smoothly rotating magnetic fields. Their manual detection has become a relatively common practice over decades, although visual detection can be time-consuming and subject to observer bias. Our study proposes a pipeline that utilizes two supervised binary classification machine-learning models trained with solar wind magnetic properties to automatically detect large-scale FRs and additionally determine their geoeffectiveness. The first model is used to generate a list of autodetected FRs. Using the properties of the southward magnetic field, the second model determines the geoeffectiveness of FRs. Our method identifies 88.6% and 80% of large-scale ICMEs (duration ≥ 1 day) observed at 1 au by the Wind and the Solar TErrestrial RElations Observatory missions, respectively. While testing with continuous solar wind data obtained from Wind, our pipeline detected 56 of the 64 large-scale ICMEs during the 2008–2014 period (recall = 0.875), but also many false positives (precision = 0.56), as we do not take into account any additional solar wind properties other than the magnetic properties. We find an accuracy of 0.88 when estimating the geoeffectiveness of the autodetected FRs using our method. Thus, in space-weather nowcasting and forecasting at L1 or any planetary missions, our pipeline can be utilized to offer a first-order detection of large-scale FRs and their geoeffectiveness.