72 research outputs found

    Dual function filtration and catalytic breakdown of organic pollutants in wastewater using ozonation with titania and alumina membranes

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    Water recycling via treatment from industrial and/or municipal waste sources is one of the key strategies for resolving water shortages worldwide. Polymer membranes are effective at improving the water quality essential for recycling, but depend on regular cleaning and replacement. Pure ceramic membranes can reduce the cleaning need and last significantly longer in the same applications while possessing the possibility of operating in more aggressive environments not suitable for polymers. In the current work, filtration using a tubular ceramic membrane (�-Al2O3 or TiO2) was combined with ozonation to remove organic compounds present in a secondary effluent to enhance key quality features of the water (colour and total organic carbon, TOC) for its potential reuse. ‘Bare’ commercial �-Al2O3 filters (pore size ∼0.58 �m) were tested as a microfiltration membrane and compared with the more advanced catalytically active TiO2 layer that was formed by the sol–gel method. The presence of anatase with a 4 nm pore size at the membrane surface was confirmed by X-ray diffraction (XRD) and N2 adsorption. Filtration of the effluent over a 2 h period led to a reduction in flux to 45% and 60% of the initial values for the �-alumina and TiO2 membrane, respectively. However, a brief dose (2 min) of ozone at the start of the run resulted in reductions to only 70% of the initial flux for both membranes. It is likely that the oxide’s functional property facilitated the formation of hydroxyl (OH•) or other radicals on the membrane surface from ozone decomposition which targeted the breakdown of organic foulants thus inhibiting their deposition. Interestingly, the porous structure therefore acted in a synergistic, dual function mode to physically separate the particulates while also catalytically breaking down organic matter. The system also greatly improved the efficiency of membrane filtration for the reduction of colour, A254 (organics absorption at the wavelength of 254 nm) and TOC. The best performance came from combined ozonation (2 min ozonation time with an estimated applied ozone dose of 8 mg L−1) with the TiO2 membrane, which was able to reduce colour by 88%, A254 by 75% and TOC by 43%. It is clearly evident that a synergistic effect occurs with the process combination of ozonation and ceramic membrane filtration demonstrating the practical benefit of combining ceramic membrane filtration with conventional water ozonation

    Cosmological perturbations in SFT inspired non-local scalar field models

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    We study cosmological perturbations in models with a single non-local scalar field originating from the string field theory description of the rolling tachyon dynamics. We construct the equation for the energy density perturbations of the non-local scalar field and explicitly prove that for the free field it is identical to a system of local cosmological perturbation equations in a particular model with multiple (maybe infinitely many) local free scalar fields.Comment: 21 pages, no figures, v3: presentation improved, results unchanged, references adde

    The Physics of the B Factories

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    This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

    Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970–2016: a systematic analysis for the Global Burden of Disease Study 2016

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    BACKGROUND: Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016. METHODS: We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone. FINDINGS: Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, an

    Moscas ectoparasitas (Diptera, Hippoboscoidea, Nycteribiidae) de morcegos (Mammalia, Chiroptera) do Estado do Paraná, Brasil. I. Basilia, taxonomia e chave pictórica para as espécies Batflies (Diptera, Hippoboscoidea, Nycteribiidae) from Paraná State, Brazil. I. Basilia, taxonomy and pictorial key to species

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    <abstract language="eng">A survey of nicteribiid batflies (Diptera: Nycteribiidae) was done in Paraná State, Brazil. Seven species of Basilia Miranda Ribeiro, 1903 were recorded. Basilia ortizi Machado-Allison, 1963 is a new record for Brazil.. Two species are new records for Paraná State, Basilia carteri Scott, 1936 and Basilia juquiensis Guimarães, 1946. The male of B. juquiensis Guimarães is characterized. Basilia lindolphoi sp. n. is described. Pictorial keys to species are presented, and female abdomens are illustrated
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