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Thermochemical systems for energy conversion are just at the interface between chemical and thermal engineering because the final aim is a transformation of energy, while the specific tool is a thermally driven chemical reaction. Designing the efficient systems calls for appropriate choice of chemical process, comprehensive analysis of its thermodynamics and kinetics, intensification of heat and mass transfer, intelligent integration of components into overall heat device, etc. This paper reviews the joint activity of the six institutes from the four countries on applying chemical reactions in modern devices for production of cold, which are driven by solar heat.

Water scarcity is one of the problems in water management that hinders European rivers in reaching a good ecological status as defined in the European Water Framework Directive. Water scarcity often coincides with high water temperature and low water quality. High water temperatures decrease the oxygen supply and often coincide with low flows that tend to increase the load of various compounds that affect the equilibrium in the ecosystem. The river Meuse regularly encounters situations of low water flow. In these situations, the river Rur, an important tributary of the river Meuse in Germany, contributes significantly to the Meuse discharge. Climate change can lead to more frequent periods of water scarcity. Moreover, plans exist to divert water from the Rur to former brown coal quarries in Germany. This exploratory study examines the relationships between discharge, water temperature and water quality under future climate change and water diversion scenarios in low-flow situations for the rivers Meuse and Rur. The results of the study confirm that rising air temperatures as a result of climate change will lead to higher water temperatures which will negatively impact the water quality of the Meuse in particular. Despite the fact that the contribution of the Rur has a positive impact on the water quality of the Meuse, the results suggest that effects of plans to divert water from the Rur may be small on average. However, the impact of the diversion may be stronger on individual hot summer days with low water levels when the Rur contributes significantly to the discharge of the Meuse.

ABSTRACTThis case study of the Society of Environmental Toxicology and Chemistry (SETAC) workshop MODELINK demonstrates the potential use of mechanistic effects models for macrophytes to extrapolate from effects of a plant protection product observed in laboratory tests to effects resulting from dynamic exposure on macrophyte populations in edge‐of‐field water bodies. A standard European Union (EU) risk assessment for an example herbicide based on macrophyte laboratory tests indicated risks for several exposure scenarios. Three of these scenarios are further analyzed using effect models for 2 aquatic macrophytes, the free‐floating standard test species Lemna sp., and the sediment‐rooted submerged additional standard test species Myriophyllum spicatum. Both models include a toxicokinetic (TK) part, describing uptake and elimination of the toxicant, a toxicodynamic (TD) part, describing the internal concentration‐response function for growth inhibition, and a description of biomass growth as a function of environmental factors to allow simulating seasonal dynamics. The TK–TD models are calibrated and tested using laboratory tests, whereas the growth models were assumed to be fit for purpose based on comparisons of predictions with typical growth patterns observed in the field. For the risk assessment, biomass dynamics are predicted for the control situation and for several exposure levels. Based on specific protection goals for macrophytes, preliminary example decision criteria are suggested for evaluating the model outputs. The models refined the risk indicated by lower tier testing for 2 exposure scenarios, while confirming the risk associated for the third. Uncertainties related to the experimental and the modeling approaches and their application in the risk assessment are discussed. Based on this case study and the assumption that the models prove suitable for risk assessment once fully evaluated, we recommend that 1) ecological scenarios be developed that are also linked to the exposure scenarios, and 2) quantitative protection goals be set to facilitate the interpretation of model results for risk assessment. Integr Environ Assess Manag 2016;12:82–95. ©2015 SETAC

AbstractThe transient expression of recombinant biopharmaceutical proteins in plants can suffer inter‐batch variation, which is considered a major drawback under the strict regulatory demands imposed by current good manufacturing practice (cGMP). However, we have achieved transient expression of the monoclonal antibody 2G12 and the fluorescent marker protein DsRed in tobacco leaves with ∼15% intra‐batch coefficients of variation, which is within the range reported for transgenic plants. We developed models for the transient expression of both proteins that predicted quantitative expression levels based on five parameters: The OD600nm of Agrobacterium tumefaciens (from 0.13 to 2.00), post‐inoculation incubation temperature (15–30°C), plant age (harvest at 40 or 47 days after seeding), leaf age, and position within the leaf. The expression models were combined with a model of plant biomass distribution and extraction, generating a yield model for each target protein that could predict the amount of protein in specific leaf parts, individual leaves, groups of leaves, and whole plants. When the yield model was combined with a cost function for the production process, we were able to perform calculations to optimize process time, yield, or downstream costs. We illustrate this procedure by transferring the cost function from a production process using transgenic plants to a hypothetical process for the transient expression of 2G12. Our models allow the economic evaluation of new plant‐based production processes and provide greater insight into the parameters that affect transient protein expression in plants. Biotechnol. Bioeng. 2012; 109: 2575–2588. © 2012 Wiley Periodicals, Inc.

Green macroalgae are an abundant and undervalued biomass with a specific cell wall structure. In this context, different pretreatments, namely ethanol organosolv (Org), alkaline, liquid hot water (LHW), and ionic liquid (IL) pretreatments, were applied to the green macroalgae Ulva lactuca biomass and then evaluated. Their effects on chemical composition, biomass crystallinity, enzymatic digestibility, and theoretical ethanol potential were studied. The chemical composition analysis showed that the Org and LHW pretreatments allowed the highest glucan recovery (80.8 ± 3.6 and 62.9 ± 4.4 g/100 g DM, respectively) with ulvan (80.0 and 99.1%) and hemicellulose (55.0 and 42.3%) removal. These findings were in agreement with both thermogravimetric analysis and scanning electron microscopy results that confirm significant structural changes of the pretreated biomasses. It was found that the employed pretreatments did not significantly affect the cellulose crystallinity; however, they both increased the whole crystallinity and the enzymatic digestibility. This later reached 97.5% in the case of LHW pretreatment. Our results showed high efficiency saccharification of Ulva lactuca biomass that will constitute the key step of the implementation of a biorefinery process.