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Abstract Electricity dispatch is a difficult optimisation problem that aims at minimising total fuel cost while satisfying system power demand and certain thermal unit constraints. Modelling valve point effects, multiple fuel options or transmission losses brings non-convexity and non-smoothness into the mathematical models. This paper proposes mathematical programming-based models for valve point effects, multiple fuel options and transmission loss problems respectively. Mathematical programming leads to robust and rigorous optimisation methods for these problems. The applicability of the proposed methods is demonstrated through a number of case studies. For all the case studies, the corresponding methods identify power schedules at least as good as or better than the best known in literature.

We use enhanced-sampling simulations with an effective collective variable to study the activation of the β2-adrenergic receptor in the presence of ligands with different efficacy. The free-energy profiles are computed for the ligand-free (apo) receptor and binary (apo-receptor + G-protein α-subunit and receptor + ligand) and ternary complexes. The results are not only compatible with available experiments but also allow unprecedented structural insight into the nature of GPCR conformations along the activation pathway and their role in the activation mechanism. In particular, the simulations reveal an unexpected mode of action of partial agonists such as salmeterol and salbutamol that arises already in the binary complex without the G-protein. Specific differences in the polar interactions with residues in TM5, which are required to stabilize an optimal TM6 conformation that facilitates G-protein binding and receptor activation, play a major role in differentiating them from full agonists.

3-(Hydroxy(phenyl)phosphoryl)propanoic acid (HPA) has a strong coordination ability for Zn2+/metal anodes which not only form sphere micelles that promote the uniform transmission of Zn2+ but also enhance the preferential adsorption on anodes.

Abstract Conventional polymer electrolyte fuel cells (PEFCs) require a means of placing the series of laminar components that make up cells under mechanical compression so as to ensure effective electrical conduction, mass transport and gas-tight operation. This review describes the effect of mechanical compression and dimensional change on the components of PEFCs and reviews the range of methods used to achieve desired stack compression. The case is made for improved understanding of the mechanisms of fuel cell component compression and greater attention to the development of technological approaches for stack compression.

Abstract This paper assesses the effects of a global emissions trading scheme (GETS) for international aviation and shipping as a way of reducing emissions of both greenhouse gases (GHG) and other atmospheric emissions that lead to air pollution. A prior assessment of such integration requires the coupling of energy–environment–economy (E3) global modelling of mitigation policies with the atmospheric modelling of pollution sources, mixing and deposition. We report the methodology and results of coupling of the E3MG model and the global atmospheric model, p-TOMCAT. We assess the effects of GETS on the concentrations of atmospheric gases and on the radiative forcing, comparing a GETS scenario to a reference BASE scenario with higher use of fossil fuels. The paper assesses the outcome of GETS for atmospheric composition and radiative forcing for 2050. GETS on international shipping and aviation reduces their CO 2 and non-CO 2 emissions up to 65%. As a consequence atmospheric concentrations are modified and the radiative forcing due to international transport is reduced by different amounts as a function of the pollutant studied (15% for CO 2 , 35% for methane and up to 50% for ozone).

Abstract As the financial and physical markets for energy have increasingly become intertwined, energy trade is also covered by financial legislation. The European Commission wishes to strengthen this financial regulation of energy trade. It has put forward a set of regulatory proposals aimed at stabilizing financial markets and limiting volatility of energy prices. The most noteworthy are EMIR, MAD, REMIT and the revised MiFID. Key elements are transparency, new trading venues, central clearing obligations and mandatory transaction reporting. This article evaluates the likely outcomes for energy markets, given the new incentives for market parties. It argues that although there is no ground to exempt particular energy market participants such as energy companies from financial legislation, increased regulation will not necessarily bring about the effects the Commission desires. The causal link between derivatives trading and volatility of energy prices is not known precisely and many of the economic effects of the proposed legislation are theoretically and empirically ambiguous. Moreover, potentially conflicting instruments and objectives risk policy inconsistency.

This study contributes to combustion research and fuel development by reporting the effect of the phenyl group in alkylbenzenes on combustion characteristics and exhaust gas emissions. The experiments were conducted in a single cylinder compression ignition engine. Three alkylbenzenes with long alkyl chains, three alkane/toluene mixtures and seven alkanes were tested. Additionally, three alcohols were tested to allow comparisons between the effects of a phenyl group and a hydroxyl group. It was found that both the phenyl group and the hydroxyl group have a significant effect on the ignition delay and the exhaust gas emissions. The rate of alkylbenzene combustion was lower than that of the corresponding alkane. Additionally, the phenyl groups in alkane/toluene mixtures had longer ignition delays than the corresponding alkylbenzene molecules. Adding a hydroxyl group to an alkane was observed to increase the ignition delay more than the addition of a phenyl group. It is suggested that these changes in ignition delay are mainly caused by the formation of relatively stable radicals in the combustion of compounds with a phenyl group. The presence of a phenyl group in the fuel molecule also increased the NOx emissions and the mass of particulate emissions in the exhaust gas compared to both alcohols and alkanes.

A human lymphoblastoid cell line (Raji) developed macrocytosis after 5-7 days when cultured in the presence of 100, 250 and 500 mg ethanol/dl. The degree of macrocytosis was least with 100 mg/dl and greatest with 500 mg/dl. The macrocytosis was associated with a proportionate increase in the total protein content per cell, was reversed after culture in the absence of ethanol and was uninfluenced by the supplementation of the culture medium with 50 micrograms folic or folinic acids per millilitre. Ethanol also caused a substantial prolongation of the cell doubling time at concentrations of 250 and 500 mg/dl (but not 100 mg/dl) and this was associated with some increase in the proportion of non-viable cells in the cultures. Furthermore, ethanol increased the incorporation of 3H-leucine into protein per femtolitre of cell volume. It is proposed that the ethanol-induced macrocytosis may have developed as a consequence of the stimulation of the rate of protein synthesis within a normal or prolonged cell cycle.