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Proton nuclear magnetic resonance (NMR) spectroscopy was used to follow glucose metabolism in Crithidia luciliae. Parasites were grown aerobically and anaerobically in culture, with glucose as the major carbon source and 1H NMR spectra were acquired for the cell free medium. The 1H NMR resonances of metabolites utilised and produced during cell growth were identified by difference spectroscopy, and quantitated from standard curves using 3-trimethylsilyl propionate-2,2,3,3-d4 sodium salt as an internal standard. The major metabolites produced by C. luciliae grown aerobically on 8 mM glucose were succinate, pyruvate, acetate and ethanol, in final concentrations in the media when the cells entered stationary phase of 8.5 +/- 0.5, 5.0 +/- 0.3, 2.1 +/- 0.2 and 2.5 +/- 0.6 mM, respectively. The production of succinate and pyruvate, but not acetate and ethanol, followed closely the growth curve of the parasites. Succinate was also measured enzymically and glucose using an autoanalyser. In both cases the results correlated well with the NMR data. The amounts of end products formed were greater than could be accounted for by the utilisation of glucose or any other metabolite observable in the 1H NMR spectra. There was approximately one extra atom of carbon for each molecule of succinate formed, supporting the view that succinate is produced via phosphoenolpyruvate carboxykinase and carbon dioxide fixation. Anaerobically the same major metabolites were produced, but with a decreased ratio of succinate to acetate and ethanol. The formation of glycerol from glucose was not observed under these conditions.

Abstract This paper presents a numerical study of the particle cluster behavior in a riser/downer reactor by means of combined computational fluid dynamics (CFD) and discrete element method (DEM), in which the motion of discrete particles is obtained by solving Newton's equations of motion and the flow of continuum gas by the Navier–Stokes equations. It is shown that the existence of particle clusters, unique to the solid flow behavior in such a reactor, can be predicted from this first principle approach. The results demonstrate that there are two types of clusters in a riser and downer: one is in the near wall region where the velocities of particles are low; the other is in the center region where the velocities of particles are high. While the extent of particle aggregation appears to be similar, the duration time for the first type in a downer is shorter than in a riser. Furthermore, it is demonstrated that the formation of clusters is affected by a range of variables related to operational conditions, particle properties, and bed properties and geometry. The increase of solid volume fraction, sliding and rolling friction between particles or between particles and wall, or damping coefficient can enhance the formation of clusters. The use of multi-sized particles can also promote the formation of clusters. But the increase of gas velocity or use of a wider bed can suppress the formation of clusters. The van der Waals force may enhance the formation of clusters when solid concentration is high but suppress the formation of clusters near the wall region when solid concentration is low.

Risk preference is an important factor in electricity market strategy analysis and decision-making. The existing methods of risk preference analysis need to design and execute questionnaires or experiments on the subjects, and hence are costly and time-consuming for bidding in electricity markets. This article proposes a new method of data-driven risk preference analysis for power generation plants based on historical data and inverse reinforcement learning. Historical data are transformed to the transition function model according to the specific market mechanism. An adjusted inverse reinforcement learning model is thereafter proposed along with the optimization objective and technical constraints. The proposed method is tested in a simulated electricity market environment using the Australian Energy Market Operator (AEMO) day-ahead bidding data. Simulation results show that 1) thermal power plants prefer to adjust risk preferences within the day; 2) apart from the thermal power plants, the rest types of power plants are risk-neutral; 3) the daily risk preference trend of the thermal power plants varies in different seasons and is closely related to the load level.

CuInSe2 thin films were cathodically electrodeposited on conducting substrates from aqueous solutions containing CuCl, InCl3 and SeO2. Structural characterization were carried out by microprobe, X-ray diffraction and electron microscopy studies. The presence of chalcopyrite phase CuInSe2 was confirmed from X-ray studies. Optical absorption studies indicated band gap values of about 1.1 eV. Electrical characterization was carried out by Hall effect and resistivity studies. The room temperature resistivity and mobility were found to be 2.15×10−3 ω cm and 8.1 cm2 V−1s−1 respectively for p-type films. Diffusion of In into p-type films converted them to n-type. Photovoltaic and photoelectrochemical solar cells were fabricated with Mo/p-CuInSe2/CdS/Au and Mo/n-CuInSe2/I1−I3−/C configurations. The open circuit photovoltage and short circuit current densities were 188 mV and 0.056 mA cm−2 for photovoltaic cells and 172 mV and 2.75 mA cm−2 for photoelectrochemical cells under 100 mW cm−2 intensity of illumination, without optimisation.

Abstract Of the materials of current research interest in thin-film photovoltaics, Ru and Te are amongst the nine rarest elements in the earth's crust, with In and Se in positions 11 and 14, raising the issue as to what constraints, if any, are placed on future thin-film photovoltaic manufacturing volumes by such scarcity. Te provides an interesting case study since more than 600 t has been incorporated into CdTe modules fielded to-date, with CdTe technology recently consolidating its position as the most successful commercial thin-film technology. The origin and impacts of recent fluctuating Te market conditions are discussed as are new insights into long-term supply from Cu refining.

The restructured market for electricity in the UK has experienced a systematic pattern of price spikes associated with the use of market power by the two dominant generators. Partly in response to this problem, the share of capacity owned by any individual generator after restructuring was limited in Victoria, Australia. As a result, a much more competitive market resulted with prices substantially lower than they were under regulation. Nevertheless, an erratic pattern of price spikes exists and the price volatility is a potential problem for customers. This paper argues that the use of a uniform price auction for electricity markets exacerbates price volatility. A discriminatory price auction is proposed as a better alternative that would reduce the responsiveness of price to errors in forecasting total load.

Abstract In this study, a new method to reduce the thermomechanical stress in silicon solar cells induced during the cell interconnection process is proposed. By repositioning the rear pads such that the silicon solar cells are bonded to the front copper conductors ended at the same locations as the outer edges of the outermost rear pads along the busbar direction. Finite element modelling predicts that stress reduction of >50% was achieved when solar cells are interconnected by conventional tabbing or Multi-busbars (MBB) and it was confirmed by the derived stress measured by the micro-Raman spectroscopy. Front busbars terminated with a reduced contact area can further increase the tolerance of any potential misalignment arising from process variations.