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Abstract On the basis of experience acquired during a study on the reliability of PWR vessels, this text illustrates the points requiring more thorough investigation in order to raise the confidence level of the estimation of the reliability of the vessel. We also offer evidence of the need to develop, for already existing installations, adaptive type reliability models allowing a continually updated estimate of the reliability of the plant.

This article presents an environmentally friendly, low‐cost polymer nanocomposite, polyvinyl alcohol/sodium alginate‐graphene‐zinc oxide (PVA‐SA/G‐ZnO) based triboelectric nanogenerator by spin coating. ZnO quantum dots of average particle size <10 nm and the graphene oxide (GO)‐doped ZnO are synthesized by co‐precipitation following ageing. ZnO and G‐ZnO particles are filled into the PVA/SA blend system using the solution mixing method. Spin‐coated films of ≈1.2 μm and casted films of 120 μm thicknesses were used to prepare triboelectric nanogenerators (TENGs) to test the output voltage performances. Irrespective of the thickness values, the films gave similar voltage responses with contact electrification. This illustrates triboelectric power generation as a surface charge carrier phenomenon based on morphological analyses by scanning electron microscope (SEM) and atomic force microscopy (AFM). The maximum output voltage of 0.24 V was approximately 5 times higher for the PVA/SA composite containing 2 wt% G‐ZnO nanomaterials compared to the neat polymer are obtained. The nanocomposites also demonstrate excellent dielectric constant (22 times higher) values, suggesting the role of the biodegradable thin‐film TENGs in various self‐powering devices.

AbstractDecarbonising the energy system requires high shares of variable renewable generation and sector coupling like power to heat. In addition to heat supply, heat pumps can be used in future energy systems to provide flexibility to the electricity system by using the thermal storage potential of the building stock and buffer tanks to shift electricity demand to hours of high renewable electricity production. Bridging the gap between two methodological approaches, we coupled a detailed building technology operation model and the open-source energy system model Balmorel to evaluate the flexibility potential that decentral heat pumps can provide to the electricity system. Austria in the year 2030 serves as an example of a 100% renewable-based electricity system (at an annual national balance). Results show that system benefits from heat pump flexibility are relatively limited in extent and concentrated on short-term flexibility. Flexible heat pumps reduce system cost, CO2 emissions, and photovoltaics and wind curtailment in all scenarios. The amount of electricity shifted in the assessed standard flexibility scenario is 194 GWhel and accounts for about 20% of the available flexible heat pump electricity demand. A comparison of different modelling approaches and a deterministic sensitivity analysis of key input parameters complement the modelling. The most important input parameters impacting heat pump flexibility are the flexible capacity (determined by installed capacity and share of control), shifting time limitations, and cost assumptions for the flexibility provided. Heat pump flexibility contributes more to increasing low residual loads (up to 22% in the assessed scenarios) than decreasing residual load peaks. Wind power integration benefits more from heat pump flexibility than photovoltaics because of the temporal correlation between heat demand and wind generation.

In 1981 the Giprokhimmash suggested organizing the wide introduction of full secondary power source use at the Sumsk Severno industrial unit plants, including a considerable number of existing, under construction, and planned undertakings from various departments and services and predominantly the very large plants and production associations of Minkhimmash in the Sumsk Severuo industrial unit having large unused secondary power source reserves.

Clostridium kluyveri is an anaerobic microorganism that is well-known for producing butyrate and hexanoate using ethanol and acetate. It is also an important bacterium in the production of Chinese strong flavour baijiu (SFB). To obtain a comprehensive understanding of its metabolism, a curated genome-scale metabolic model (GSMM) of C. kluyveri, including 708 genes, 994 reactions, and 804 metabolites, was constructed and named iCKL708. This model was used to simulate the growth of C. kluyveri on different carbon substrates and the results agreed well with the experimental data. The butyrate, pentanoate, and hexanoate biosynthesis pathways were also elucidated. Flux balance analysis indicated that the ratio of ethanol to acetate, as well as the uptake rate of carbon dioxide, affected hexanoate production. The GSMM iCKL708 described here provides a platform to further our understanding and exploration of the metabolic potential of C. kluyveri.

Dried, milled perennial ryegrass samples were processed using chemical and physical treatments and the extracted cellulose products were analysed for yield, crystallinity by X-ray Diffraction (XRD) and for purity using Thermogravimetric Analysis (TGA), Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS) and Fourier Transform Infrared (FTIR) spectroscopy. Extraction protocols examined the use of chemical chelation, acid and alkaline hydrolysis, along with physical degradation methods. Highest product yields were obtained using single step chemical protocols followed by physical processing, however, these products had low crystallinity and higher amorphous fraction content. Multistep chemical processing to completely remove hemicellulose and lignin with an alkali refluxing step, delivered lower yielding cellulose products of greater crystallinity and purity. In combination, the four instrumental techniques highlighted removal of amorphous fractions, providing rapid, accurate compositional data on the extracted cellulose products.

There is growing interest in zebrafish as a model organism in behavioral pharmacology research. Several anxiety behaviors have been characterized in zebrafish, but the effect of anxiolytic drugs on these parameters has been scarcely studied. The purpose of this work was to assess the predictive validity of acute treatment with anxiolytic drugs on behavioral parameters of anxiety. In the first task we simultaneously observed behavior of adult zebrafish on four parameters: height in the tank, locomotion, color, and shoal cohesion. The second task was the assessment of light/dark preference for 5 min. The benzodiazepines clonazepam, bromazepam, diazepam, and a moderate dose of ethanol significantly reduced shoal cohesion. Buspirone specifically increased zebrafish exploration of higher portions of the tank. In the light/dark task, all benzodiazepines, buspirone, and ethanol increased time spent in the light compartment. After treatment with anxiolytics, fish typically spent more than 60s and rarely less than 40s in the light compartment whereas controls (n=45) spent 33.3±14.4s and always less than 60s in the light compartment. Propranolol had no clear effects in these tasks. These results suggest that light/dark preference in zebrafish is a practical, low-cost, and sensitive screening task for anxiolytic drugs. Height in the tank and shoal cohesion seem to be useful behavioral parameters in discriminating different classes of these drugs.