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Abstract: Regeneration of activated carbons (ACs) after their use for benzene and toluene removal at low concentration was studied in an oxygen-containing atmosphere, analysing the effect of porosity of the adsorbent. Attention was paid to the effect of regeneration cycles on the adsorption capacity and surface chemistry of the AC. Results show that ACs with large mesopore volumes, together with wide micropore size distributions, are desired to achieve complete regeneration at low temperatures (250–300°C). The effect of successive regeneration cycles under an oxygen-containing atmosphere indicates that 250°C is suitable for regeneration of most benzene-exhausted adsorbents, whereas for toluene the process requires higher temperatures (300–350°C). The experiments show that in the case of benzene, regeneration efficiencies remain essentially constant with the number of cycles and the achieved regeneration efficiencies are close to 100%. The slight differences in regeneration efficiencies can be explained considering changes in microporosity and surface chemistry of the AC with the cycles. For regeneration of toluene-saturated AC, the regeneration percentage only remains constant for one AC, whereas some decrease is observed for the rest. This decrease can be explained, in general, by a reduction in the narrow micropore volume with cycling. [Copyright &y& Elsevier]

A previous paper showed a very effective and simple chemical activation method for the preparation of activated carbons from an anthracite that allowed to obtain different ranges of porosity. In addition, these materials were suitable for the VOC adsorption because this activation method renders AC with high volumes of narrow micropores. In this paper, the method has been successfully extended to some other precursors, such as subbituminous and lignite coals and lignocellulosic materials. The developed method permits the easy preparation of AC with very well-developed porosities and with high narrow micropore volumes.These characteristics of the AC allow to reach high adsorption capacities to VOC (benzene and toluene) at low concentrations, which are much higher than previously reported in the literature. [Copyright &y& Elsevier]

There is a direct relationship between the grade of obesity and mortality based on the increased cardiovascular diseases, cancer, etc. However, the results of studies in renal and liver allograft recipients relating obesity to morbidity and mortality are contradictory. A retrospective cohort study of 170 patients transplanted between March 1987 and July 1997 showed obesity to be identified in 77 (45.3%) patients. During the mean follow-up of 5 years posttransplantation, 16 (9.4%) patients experienced cardiovascular complications, including 10 patients with ischemic cardiac syndromes (five acute infarctions and five angina), five patients with acute cerebrovascular accidents, and one patient with intermittent lower limbs claudication. The prevalence of obesity at 1, 3, 5, 7, and 9 years after transplantation was 58.2%, 56.9%, 60.3%, 59.5%, and 66.4%, respectively. Compared with the baseline value, the BMI was increased at 1 year posttransplantation (25.78), a significant difference. No significant differences were found between the mean BMI values of patients with and without cardiovascular diseases, or overweight and morbidly obese patients compared to the normal weight population. Among liver transplant recipients, obesity was a frequent complication after transplantation, but it was not clearly associated with increased morbidity and mortality secondary to cardiovascular disease. [Copyright &y& Elsevier]

Cataclysmic Variables (CVs) are binaries in which a white dwarf accretes from a low-mass companion star. CVs are the best-suited laboratories to test our understanding of the evolution of compact, interacting binaries as they are numerous, relatively bright, and both stellar components are structurally simple. Nonetheless, while a large fraction (≃ 40 - 80 %) of the present-day Galactic CV population is expected to be old, highly evolved and to host brown dwarf companions, yet very few of these so-called "period bouncers" have been identified so far. The lack of these systems in the observed Galactic CV population possibly suggests that the physical mechanisms driving CV evolution (such as the common envelope phase, the mechanisms of angular momentum loss and/or the response of the companions to the mass loss) are still not completely understood. The Compact binary HIgh CAdence Survey (CHiCaS) is a high cadence photometric survey performing three hours of uninterrupted time series photometry at one minute cadence over 136 square degrees of sky with JAST/T80Cam. CHiCaS aims to unambiguously identify the predicted large population of period-bounce CVs via detection of binary eclipses, thus providing an observational support for the current evolutionary models of all kind of compact binaries, such as black hole binaries, X-ray transients, double degenerates or SN Ia progenitors. Moreover, CHiCaS will deliver high cadence light curves along with full-colour information for about 2.5 million sources, thus identifying several hundred thousand variable stars, including eclipsing and contact binaries, pulsating and flaring stars, which will provide a significant legacy value. [ABSTRACT FROM AUTHOR]