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An anthracitic coal-derived activated porous carbon is proposed as a promising carbon electrode material for supercapacitor (SC) applications. The specific capacitance of this activated carbon SC electrode is related to the characteristics, such as specific surface area, pore size distribution, wettability, and conductivity. In the present work, a series of anthracite-based activated carbons (ABAC) were prepared via a multistage activation process and used as electrode materials for SCs. The multistage activation experiment was developed by exploring different activation temperatures, precursor/activating agent mass ratios, and process treating environments. The electrochemical performance of ABACs was evaluated in a three-electrode testing system. Multiple electrolytes were utilized, such as 1 M sulfuric acid (H2SO4) and 1 and 6 M potassium hydroxide (KOH) solutions. An optimum ABAC electrode was obtained, characterized by its largest wettability and superior conductivity, and achieved excellent electrochemical performance. The three-electrode system exhibited a specific capacitance of 288.52 and 260.30 F/g at 0.5 A/g in the 1 M H2SO4and 6 M KOH electrolytes, respectively. It was found that moderate multistage activation temperatures are beneficial for the electrolyte uptake which enhances the specific capacitance. The high content of the oxygen functional groups on the activated carbon surface greatly improved its specific capacitance due to the increase in wettability. In the 1 M H2SO4electrolyte, the working electrode exhibited better performance than in 1 M KOH because the ion diameter in the acidic electrolyte was more suitable for pore diffusion. The concentrated KOH electrolyte leads to an increase in specific capacitance due to increased ions being adsorbed by a certain number of the hydrophilic pores. Moreover, the specific capacitance of the optimum ABAC sample remained at 95.4% of the initial value after 1000 galvanostatic charge–discharge tests at 0.5 A/g, which is superior to the performance of SC grade commercial carbon.

Political commentator John McLaughlin is a caricature of himself both on and off the camera. Working for him is so stressful that one of his staff keeps a small Japanese rock garden on his desk. Constant contact with him is toxic, but the US, usually indifferent to Washington politics, needs him.

Your agenda-setting series on the closing of the Conservative mind accurately highlights in Ferdinand Mount's article ('Boris Johnson and the hollow men', 21 June) one of the key causes of [...]

Rare earth elements (REEs) are valuable raw materials which are in great demand in modern high technology industries. Developing methods to produce/recover REEs from waste is significant to the national security of any developed country. This study was focused on investigating the use of supercritical CO2(sCO2) to extract REEs from anthracite acid mine drainage (AMD). Four different mine drainage water source locations at Blaschak Coal Corp. in Pennsylvania, USA were selected for sample collection. An extraction process was developed and demonstrated for two of those water sources containing the highest concentration of REEs. A method involving metal ion coagulation, their dissolution from the sludge into a concentrated aqueous HNO3solution, complexation with organic ligands and sCO2extraction was developed to recover REEs from AMD. Specifically, sodium aluminate (NaAlO2) was used as the coagulant to concentrate REEs from the AMD into a solid precipitate. Consequently, over 99% of the REEs in AMD is concentrated in the remaining sludge. During the coagulation process, the effects of pH and NaAlO2concentration on REE precipitation were investigated. Fuming nitric acid (HNO3) was used to digest the pre-concentrated sludge and tributyl phosphate (TBP) was used to form REE/TBP/HNO3, a non-polar complex with selected REEs, specifically, cerium (Ce), lanthanum (La) and neodymium (Nd). HNO3concentration and organic/aqueous phase ratio were considered as the variables to improve complexation efficiency. Dynamic extraction experiments using sCO2and REE/TBP/HNO3solutions were then conducted at optimal conditions of 60 °C and 20 MPa. The overall REE extraction efficiencies are found to increase with the atomic number of the REE. As a result, the average overall REE extraction efficiencies of 41.8%, 40.1% and 58.2% for Ce, La and Nd, respectively, are obtained. The potential improvements in the overall extraction efficiency are also discussed.

Stochastic kinetic models (SKMs) are increasingly used to account for the inherent stochasticity exhibited by interacting populations of species in areas such as epidemiology, population ecology and systems biology. Species numbers are modelled using a continuous-time stochastic process, and, depending on the application area of interest, this will typically take the form of a Markov jump process or an Itô diffusion process. Widespread use of these models is typically precluded by their computational complexity. In particular, performing exact fully Bayesian inference in either modelling framework is challenging due to the intractability of the observed data likelihood, necessitating the use of computationally intensive techniques such as particle Markov chain Monte Carlo (particle MCMC). It is proposed to increase the computational and statistical efficiency of this approach by leveraging the tractability of an inexpensive surrogate derived directly from either the jump or diffusion process. The surrogate is used in three ways: in the design of a gradient-based parameter proposal, to construct an appropriate bridge and in the first stage of a delayed-acceptance step. The resulting approach, which exactly targets the posterior of interest, offers substantial gains in efficiency over a standard particle MCMC implementation. [ABSTRACT FROM AUTHOR]

Several letters to the editor are presented in response to articles in previous issues including a story on actor John Travolta in the April 3, 1978 issue, the comparison between the bands, Bee Gees and The Beatles, and the "Can the U.S. Defend Itself?" in the April 3, 1978 issue.

This article examines how the OECD Tax Information Exchange Regime interacts with common law and constitutional protection of rights of privacy. Recent case law in offshore jurisdictions illustrates the importance of court intervention to guard against the risk of improper and over-enthusiastic administrative action.

Several letters to the editor are presented in response to articles in previous issues including "Will Japan really change," in the May 12, 1986 issue, "From coast to coast, the push is on to limit liability," in the April 28, 1986 issue and the "Tax reform that makes sense," in the May 19, 1986 issue of the journal.

Presents several letters to the editor. Comments on the article "Seduced by Civility;" Criticisms of religious lefts; Discussion on ethical culture's interest in civility.

The article focuses on post bush fire forensic investigation in Australia that has recorded 569 deaths as of 2008. The article claims that there is no typical bush fire scenario or circumstances where people perish but it shows disturbing trends. As more fatalities are recorded in open field than in houses, fire agencies encourage able bodied residents to stay and defend their properties in case of wildfires.

Presents letters to the editor referencing articles and topics discussed in the previous issues of the journal "The Nation." Comments on the drug case of federal judge, Jack Weinstein; Discussion on the contribution of Celestial Seasoning Inc. towards environmental protection; Focuses on the non distribution of books, magazines and films with sexual content.

Abstract The challenging problem of conducting fully Bayesian inference for the reaction rate constants governing stochastic kinetic models (SKMs) is considered. Given the challenges underlying this problem, the Markov jump process representation is routinely replaced by an approximation based on a suitable time-discretisation of the system of interest. Improving the accuracy of these schemes amounts to using an ever finer discretisation level, which in the context of the inference problem, requires integrating over the uncertainty in the process at a predetermined number of intermediate times between observations. Pseudo-marginal Metropolis–Hastings schemes are increasingly used, since for a given discretisation level, the observed data likelihood can be unbiasedly estimated using a particle filter. When observations are particularly informative, an auxiliary particle filter can be implemented, by propagating particles conditional on the next observation. Recent work in state-space settings has shown how the pseudo-marginal approach can be made much more efficient by correlating the underlying pseudo-random numbers used to form the estimate of likelihood at the current and proposed values of the unknown parameters. This approach is extended to the time-discretised SKM framework by correlating the innovations that drive the auxiliary particle filter. The resulting approach is found to offer substantial gains in efficiency over a standard implementation. [ABSTRACT FROM AUTHOR]

Few modern trusts exist without the use of corporate and quasi-corporate holding vehicles. This article seeks to explore the potential for beneficiaries to bring mixed, multiple derivative claims to recover against wrongdoers whose actions have caused the loss of trust assets, when a superficially simple claim against trustees for mismanagement may be met with arguments about exclusion clauses and reflective loss. Recent case law suggests it to be feasible for a beneficiary to use multiple derivative suits.

Acute asphyxia results in AVP hypersecretion in fetal sheep. Since acidosis, hypoxia, and hypercapnea occur simultaneously with asphyxia, it is unclear which is primarily responsible for AVP release. We have shown that hypoxia has no effect until aortic PO2(PaO2) is <12mmHg, and AVP levels were only 10±3μU/ml ([Xmacr ;[plusmn;SE). To further examine the asphyxial components in fetal AVP release, we studied the effects of metabolic acidosis in 8 fetal sheep at 137±1.4 days. Each was infused with .03-.07mEq NH4Cl/min·kg for 120min while monitoring mean arterial pressure (MAP), heart rate (HR), PaO2, pHa, and PaCO2, and plasma AVP before, during (20min intervals) and repeatedly after NH4Cl. MAP, PaO2, and PaCO2were unchanged; pHa fell progressively from 7.376±.012 to 6.986±.066*during NH4Cl, rising to 7.356±.021 by 24h. Plasma AVP rose gradually from 2.85±.23 to 5.26±1.1μU/ml*during NH4Cl, falling to 2.77±.41 by 4h. After NH4Cl, HR rose 24±1.1%*. The rise in AVP during NH4Cl was linearly correlated with pHa, r=-.67 (p<.0001, n=37), and PaO2tended to rise. In only one animal (not included), with pH=7.12 and PaO2=12mmHg, AVP rose >8μU/ml, 30.2μU/ml. We conclude that: 1) acidosis, like hypoxemia alone, does not result in marked fetal AVP release; 2) whereas AVP release is related linearly to pHa, there appears to be a threshold value for PaO2; and 3) acidosis and hypoxia appear synergistic for AVP release, but the role of PaCO2is unknown. *p<.05.