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Efficiency of energy resource use is a key factor for a sustainable energy future. By matching the exergy levels of supply and demand, Energy Quality Management (EQM) of building energy supply systems may achieve more efficient use of energy resources. Beyond this, environmental impact of energy supply systems is another essential issue. This work addresses the influence of EQM on CO 2 emissions in the operation optimization of a Distributed Energy System (DES). A multi-objective linear programming problem is formulated to reduce energy costs and increase the overall exergy efficiency. Total CO 2 emissions are evaluated for the optimized operation strategies of the DES. The operators of the DES can choose the operation strategy from the Pareto front, based on their priorities and also aware of effects on CO 2 emissions. Results demonstrate more efficient use of energy resources and reduction in CO 2 emissions through EQM, as compared with conventional energy supply systems.

Abstract Sodium-promoted vanadium oxide catalysts supported on MCM-41 and TiO 2 (anatase) were investigated for the partial oxidation of ethanol to acetaldehyde. The catalysts were prepared by incipient wetness impregnation with a vanadium oxide content of 6 wt.%. The experimental characterization was performed by X-ray diffraction (XRD), N 2 adsorption, temperature-programmed reduction (TPR), and diffuse reflectance UV–vis. Temperature-programmed oxidation (TPO) was also used to identify carbon deposits on the spent catalysts. The presence of sodium plays a strong role in the dispersion and reducibility of the vanadium species as detected by TPR analysis and optical absorption spectroscopy. While sodium addition increases the dispersion of the VO x species, its presence also decreases their reducibility. Additionally, TPO of the spent catalysts revealed that an increase in the Na loading decreases the carbon deposition during reaction. In the case of the catalysts supported on MCM-41, these modifications were mirrored by a change in the activity and selectivity to acetaldehyde. Additionally, on the VO x /TiO 2 catalysts the catalytic activity decreased with increasing sodium content in the catalyst . A model in which sodium affects dispersion, reducibility and also acidity of the supported-vanadia species is proposed to explain all these observations.

Purpose: Sustainability is one of the major key terms in our modern globalized world affected by such different but nevertheless closely interrelated issues like prosperity of worldwide trade, globally-spanning supply chains, the growing social gap and the threatening effects of climate change. The paper shows how responsible citizenship and reflective critical thinking as well as a deeper understanding of these complex interdependencies can be conveyed in a systematic way to a group of international business students in form of a one-week block seminar course in the CEMS Master-in-International-Management (MIM) program.Design/methodology/approach: The paper includes a discussion of proven course design, general key skills fostered, didactic approaches and methods employed along with feedback mechanisms and evaluation results demonstrating clearly its impact on student’s mind sets afterwards.Findings: Based on the discussions with our students and post-course reflective reports it turned out, that for many of them their perception of sustainability issues and of their own behaviour has changed during this single week because of the topics dealt with in our course.Practical implications: A well thought-out didactic approach and extraordinary commitment and dedication by the instructors is inevitable to ensure the success of such a course.Original/value: This paper explains in a compact way, how sustainability issues in global supply chain management can be tackled successfully even in such time restricted one-week block seminar. Purpose: Sustainability is one of the major key terms in our modern globalized world affected by such different but nevertheless closely interrelated issues like prosperity of worldwide trade, globally-spanning supply chains, the growing social gap and the threatening effects of climate change. The paper shows how responsible citizenship and reflective critical thinking as well as a deeper understanding of these complex interdependencies can be conveyed in a systematic way to a group of international business students in form of a one-week block seminar course in the CEMS Master-in-International-Management (MIM) program.Design/methodology/approach: The paper includes a discussion of proven course design, general key skills fostered, didactic approaches and methods employed along with feedback mechanisms and evaluation results demonstrating clearly its impact on student’s mind sets afterwards.Findings:Based on the discussions with our students and post-course reflective reports it turned out, that for many of them their perception of sustainability issues and of their own behaviour has changed during this single week because of the topics dealt with in our course.Practical implications: A well thought-out didactic approach and extraordinary commitment and dedication by the instructors is inevitable to ensure the success of such a course.Original/value: This paper explains in a compact way, how sustainability issues in global supply chain management can be tackled successfully even in such time restricted one-week block seminar.

Abstract In this study we present a fast and inexpensive method for the estimation of methane-producing archaea with a culture-based method using most probable number (MPN) counting of the metabolic product methane.

We report measurement of initial G2-chromatid breaks in normal human fibroblasts exposed to various types of high-LET particles. Exponentially growing AG 1522 cells were exposed to gamma rays or heavy ions. Chromosomes were prematurely condensed by calyculin A. Chromatid-type breaks and isochromatid-type breaks were scored separately. The dose response curves for the induction of total chromatid breaks (chromatid-type + isochromatid-type) and chromatid-type breaks were linear for each type of radiation. However, dose response curves for the induction of isochromatid-type breaks were linear for high-LET radiations and linear-quadratic for gamma rays. Relative biological effectiveness (RBE), calculated from total breaks, showed a LET dependent tendency with a peak at 55 keV/micrometer silicon (2.7) or 80 keV/micrometer carbon (2.7) and then decreased with LET (1.5 at 440 keV/micrometer). RBE for chromatid-type break peaked at 55 keV/micrometer (2.4) then decreased rapidly with LET. The RBE of 440 keV/micrometer iron particles was 0.7. The RBE calculated from induction of isochromatid-type breaks was much higher for high-LET radiations. It is concluded that the increased production of isochromatid-type breaks, induced by the densely ionizing track structure, is a signature of high-LET radiation exposure.

Abstract An attractive path to the production of hydrogen from water is a two-step thermo chemical cycle powered by concentrated sunlight from a solar tower system. In the first process step the redox system, a ferrite coated on a monolithic honeycomb absorber, is present in its reduced form while the concentrated solar energy hits the ceramic absorber. When water vapour is fed to the honeycomb at 800 °C, oxygen is abstracted from the water molecules, bond in the redox system and hydrogen is produced. When the metal oxide system is completely oxidised it is heated up for regeneration at 1100–1200 °C in an oxygen-lean atmosphere. Under those conditions and in the second process step, oxygen is set free from the redox system, so the metal oxide is being reduced and after completion of the reaction again capable for water splitting. Since the overall process consists of two core reaction steps, which need to be carried out sequentially in a reactor unit at two different temperature steps, a special process and plant concept had to be developed enabling the continuous supply of product regardless of the alternating nature of the solar reactor operation. The challenge of the process control is to keep the two core reaction temperatures constant and to ensure regular temperature switches after completion of the individual process steps, independent of the weather conditions, like DNI fluctuation, clouds and wind speed. Also start-up, the fast switching after completion of half-cycles and the shutdown must be controlled. State of the art is the manual switching of heliostats to fulfil those control tasks. This paper describes the development and use of a system model of this process. The model consists of three main parts: the simulation of the solar flux distribution at the receiver aperture, the simulation of the temperatures in the reactor modules and the simulation of the hydrogen generation. It can be used for the analysis of the operational behaviour. The model is intended to be used in the future for the control of the whole process.

We combined profiling of the bloom-forming and potentially toxigenic cyanobacterium Planktothrix rubescens using a multiparameter probe equipped with a phycoerythrin sensor (in vivo fluorometry, IVL) in Lake Mondsee, Austria, with flow cytometric live analyses of discrete samples taken from several depths in the upper 20 m of the water column. Results obtained by IVL and acoustic flow cytometry (AFC) were compared to microscopic analyses of integrated (0-21 m) water samples using fixed material. This comparison was made because the integrated samples are used for the Austrian monitoring programme according to the EU Water Framework Directive. We demonstrate that AFC provides quantitative analyses of the filaments of P. rubescens that are significantly correlated to IVF and microscopic analyses, allowing rapid (within hours) and more precise calculation of P. rubescens biomass than estimates derived from IVL. Our analysis shows that vertically integrated water samples provide unreliable information on the concentration of P. rubescens in the upper surface waters and on the peak concentration of P. rubescens within the water column. We conclude that the protocol that we developed is superior to the current monitoring practice.

After the consumption of fruit, the concentration of methanol in the human body increases by as much as an order of magnitude. This is due to the degradation of natural pectin (which is esterified with methyl alcohol) in the human colon. In vivo tests performed by means of proton‐transfer‐reaction mass spectrometry show that consumed pectin in either a pure form (10 to 15 g) or a natural form (in 1 kg of apples) induces a significant increase of methanol in the breath (and by inference in the blood) of humans. The amount generated from pectin (0.4 to 1.4 g) is approximately equivalent to the total daily endogenous production (measured to be 0.3 to 0.6 g/day) or that obtained from 0.3 liters of 80‐proof brandy (calculated to be 0.5 g). This dietary pectin may contribute to the development of nonalcoholic cirrhosis of the liver.