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The monitoring of a waste separation process in the nuclear power industry is considered. Recent advances in gamma ray emission and electrical impedance tomography mean that it is now feasible to unite these two modalities into a novel dual-modality monitoring method. This paper considers a simple model problem for the identification of a boundary between two distinct waste streams in a semi-continuous rotation separator. The simplicity of the problem affords the opportunity to demonstrate the general feasibility of the approach whilst avoiding unnecessary complications.

Effects of nicotine, administered by continuous infusion via osmotic minipumps, were studied on the operant self-administration of alcohol by rats, using a variable interval (15 s) schedule, and measuring the acquisition, maintenance, extinction and reinstatement of responding for alcohol. Doses of nicotine of 0.25, 1.25 and 7.5 mg/kg/24 h had no significant effects on the maintenance of responding for alcohol, but 5 mg/kg/24 h nicotine resulted in a significant increase in responding on the lever delivering the reward when water was substituted for the alcohol, indicating delayed extinction of responding. During infusion of 2.5 mg/kg/24 h nicotine, responding was significantly greater over the "sucrose-fading" training sessions, during acquisition of responding, when mixtures of alcohol and sucrose were provided as reward. When minipumps infusing 2.5 mg/kg/24 h nicotine were implanted after the alcohol responding had been acquired, the responding for alcohol increase during the first week of nicotine infusion, but corresponding nicotine infusion doses of 0.25, 1.25 and 7.5 had no significant effects. The results indicate that nicotine can increase operant responding for alcohol and this is crucially dependent on the dose of nicotine and the time of testing. The results have implications for the frequently encountered dependence on the combination of alcohol and nicotine.

Abstract This paper deals with the control of the series FACTS (Flexible AC Transmission Systems) devices for the coordination between their transient stability controller and POD (Power Oscillation Damping) controller in multi-machine power systems. The design aspects and their implementation in form of fuzzy-logic coordination controller are presented. Furthermore, ANFIS (Adaptive Neuro-Fuzzy Inference System) is employed for the training of the proposed fuzzy-logic controller. The local signals of the FACTS devices are applied to achieve the coordination objectives. Digital simulations of multi-machine power system subjected to a wide variety of disturbances validate the efficiency of this approach. The proposed control scheme is not only robust, but also simple and easy to be realized in power systems.

There is a widely believed myth that replacing the use of fossil fuels largely by renewable forms of energy is, with a possible exception of nuclear power, critically dependent on the development of appropriate new technologies. Accordingly, it is held that decarbonizing straight away is particularly difficult and expensive. There was a time when this idea had an element of reality, but this is no longer the case. Unfortunately, belief in this myth is shared by those in positions of influence. This paper serves to document that this presumed reality no longer holds, although the misconception may have been based on fact in the past. Whilst the survey of the available technology offered concentrates on electricity supply, it also documents that manufacture of synthetic fuels via hydrogen obtained by electrolysis of water and CO2 integrates smoothly with electricity grid stabilization as well as reducing the CO2 content of the atmosphere. The likely price and cost development in the energy market is also reviewed. In addition the role of CCS, in practice mainly capture from the air and industrial processes other than power generation is reviewed against the background of the cost effective generation of electricity by harvesting renewable forms of energy.

In the heating sector, borehole heat exchangers have become popular for supplying renewable energy. They tap into the subsurface to extract geothermal energy for heating purposes. For advanced applications, borehole heat exchangers require insulation in the upper part of the borehole either to meet legal requirements or to improve their performance. A priori numerical heat transport models of the subsurface are imperative for the systems’ planning and design. Only fully discretized models can account for depth-dependent borehole properties like insulated sections, but the model setup is cumbersome and the simulations come at high computational cost. Hence, these models are often not suitable for the simulation of larger installations. This study presents an analytical solution for the simulation of the thermal interactions of partly insulated borehole heat exchangers. A benchmark with a fully discretized OpenGeoSys model confirms sufficient accuracy of the analytical solution. In an application example, the functionality of the tool is demonstrated by finding the ideal length of a borehole insulation using mathematical optimization and by quantifying the effect of the insulation on the borehole heat exchanger performance. The presented method allows for accommodation of future advancements in borehole heat exchangers in numerical simulations at comparatively low computational cost.

AbstractBei der Reaktion Aluminium und Wasser bilden sich nach kurzen Reaktionszeiten Hydroxidschichten mit schwammiger Struktur. Mit zunehmender Reaktionszeit werden die Hydroxid kompakt, und es entsteht ein zusammenhängender Filme mit poröses Oberfläche. Bei Reaktionszeiten größer 4 Stunden bilden sich bei 98°C kristalline Formen aus.Während der anodischen Oxydation von Aluminium in Citronensäure werden dünne Hydroxidschichten, die vor der anodischen Oxydation aufgebracht wurden, in die Sperrschicht eingebaut. Hingegen wird bei der Formierung in aggressiven Electrolyten die Hydroxidschicht aufgelöst. Es kommt zur Ausbildung einer Eloxalschicht.Die Morphologie von Oxidschichten ist bei der Formierung ohne Hydroxidvorschicht in heißer Citronensäure stromdichteabhängig. Bei hohen Stromdichten wächst eine Sperrschicht, bei niedrigen eine Duplexschicht mit stark porösem Elexalschichtanteil auf.

Energy management is an enabling technique to guarantee the reliability and economy of hybrid electric systems. This paper proposes a novel machine learning-based energy management strategy for a hybrid electric bus (HEB), with an emphasized consciousness of both thermal safety and degradation of the onboard lithium-ion battery (LIB) system. Firstly, the deep deterministic policy gradient (DDPG) algorithm is combined with an expert-assistance system, for the first time, to enhance the “cold start” performance and optimize the power allocation of HEB. Secondly, in the framework of the proposed algorithm, the penalties to over-temperature and LIB degradation are embedded to improve the management quality in terms of the thermal safety enforcement and overall driving cost reduction. The proposed strategy is tested under different road missions to validate its superiority over state-of-the-art techniques in terms of training efficiency and optimization performance.

In a former study, a German lignite extract exhibited toxicity to Danio rerio and Caenorhabditis elegans and was shown to have mutagenic and dioxin-like activity. Besides the comparatively low content of known toxic polycyclic aromatic hydrocarbons (PAH), highly intensive peaks of m/z 274 and m/z 324 were observed during the chromatographic analysis. These compounds are assumed to be alkylated chrysenes and picenes (3,3,7-trimethyl-1,2,3,4-tetrahydrochrysene, 1,2-(1'-isopropylpropano)-7-methylchrysene and an isomer of the latter, 1,2,9-trimethyl-1,2,3,4-tetrahydropicene and 2,2,9-trimethyl-1,2,3,4-tetrahydropicene). These compounds are intermediates in the diagenetic formation of chrysene and picene from triterpenoids. Due to their general high abundance in lignites and the toxicity observed for the lignite extract, the mechanism-specific toxicity and bioavailability of these compounds were investigated in the present study using the approach of effect-directed analysis. After the separation of the compounds from other PAH, their mutagenic activity (Ames Fluctuation test) and dioxin-like activity (EROD activity) were studied. Both, mutation induction factor (up to 2.9±2.7) and dioxin-like activity (Bio-TEQ of 224±75 pg/g; represents the amount (pg) 2,3,7,8-tetrachlorodibenzo-p-dioxin per g coal that would provoke the same toxic effect) were rather low. Bioavailability estimated by the bioaccumulation test with Lumbriculus variegatus was also very limited. Based on the obtained results, the environmental risk of the highly abundant alkylated chrysenes and picenes in lignites is concluded to be low.