300 research outputs found

    Cost Studies of Reverse Osmosis Desalination Plants in the Range of 23,000–33,000 m3/day

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    first_pagesettingsOrder Article Reprints Open AccessArticle Cost Studies of Reverse Osmosis Desalination Plants in the Range of 23,000–33,000 m3/day by J. Feo-García 1,A. Pulido-Alonso 2ORCID,A. Florido-Betancor 3 andN. R. Florido-Suárez 4,* 1 School of Industrial and Civil Engineering, Department of Electronic and Automatic Engineering, University of Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain 2 School of Industrial and Civil Engineering, Electrical Engineering Department, University of Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain 3 Faculty of Science, University of Cádiz, 11519 Cádiz, Spain 4 School of Industrial and Civil Engineering, Department of Civil Engineering, University of Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain * Author to whom correspondence should be addressed. Water 2024, 16(6), 910; https://doi.org/10.3390/w16060910 Submission received: 18 February 2024 / Revised: 12 March 2024 / Accepted: 19 March 2024 / Published: 21 March 2024 (This article belongs to the Special Issue Advanced Desalination Technologies for Water Treatment) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract The analysis of energy consumption in reverse osmosis desalination plants is the most important and relevant factor to study, because this parameter indicates the level of efficiency and competitiveness of the plant. The direct consequence of the high specific energy consumption (SEC) of a desalination plant in the production of water is one of the main obstacles to the exponential expansion of this technology worldwide. The methodological procedure used to carry out the work is based on the analysis of energy consumption, maintenance costs, staff, membranes, and reagents of three desalination plants with a production of more than 23,000 m3/day located in the Canary Islands (Spain); all data are obtained from real analyses collected “in situ” from 2015 to 2018. One of the main objectives of the current research on desalination plants is to reduce the SEC of seawater desalination plants (SWRO), incorporating energy recovery systems (ERS) and high efficiency pumps (HEP), and to implement different operational configurations with the aim of minimizing the energy requirements necessary to obtain a good product quality at minimum production cost

    Opacity calculation for target physics using the ABAKO/RAPCAL code

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    Radiative properties of hot dense plasmas remain a subject of current interest since they play an important role in inertial confinement fusion (ICF) research, as well as in studies on stellar physics. In particular, the understanding of ICF plasmas requires emissivities and opacities for both hydro-simulations and diagnostics. Nevertheless, the accurate calculation of these properties is still an open question and continuous efforts are being made to develop new models and numerical codes that can facilitate the evaluation of such properties. In this work the set of atomic models ABAKO/RAPCAL is presented, as well as a series of results for carbon and aluminum to show its capability for modeling the population kinetics of plasmas in both LTE and NLTE regimes. Also, the spectroscopic diagnostics of a laser-produced aluminum plasma using ABAKO/RAPCAL is discussed. Additionally, as an interesting application of these codes, fitting analytical formulas for Rosseland and Planck mean opacities for carbon plasmas are reported. These formulas are useful as input data in hydrodynamic simulation of targets where the computation task is so hard that in line computation with sophisticated opacity codes is prohibitive

    Large-Scale Magnetic Fields, Dark Energy and QCD

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    Cosmological magnetic fields are being observed with ever increasing correlation lengths, possibly reaching the size of superclusters, therefore disfavouring the conventional picture of generation through primordial seeds later amplified by galaxy-bound dynamo mechanisms. In this paper we put forward a fundamentally different approach that links such large-scale magnetic fields to the cosmological vacuum energy. In our scenario the dark energy is due to the Veneziano ghost (which solves the U(1)AU(1)_A problem in QCD). The Veneziano ghost couples through the triangle anomaly to the electromagnetic field with a constant which is unambiguously fixed in the standard model. While this interaction does not produce any physical effects in Minkowski space, it triggers the generation of a magnetic field in an expanding universe at every epoch. The induced energy of the magnetic field is thus proportional to cosmological vacuum energy: ρEMB2(α4π)2ρDE\rho_{EM}\simeq B^2 \simeq (\frac{\alpha}{4\pi})^2 \rho_{DE}, ρDE\rho_{DE} hence acting as a source for the magnetic energy ρEM\rho_{EM}. The corresponding numerical estimate leads to a magnitude in the nG range. There are two unique and distinctive predictions of our proposal: an uninterrupted active generation of Hubble size correlated magnetic fields throughout the evolution of the universe; the presence of parity violation on the enormous scales 1/H1/H, which apparently has been already observed in CMB. These predictions are entirely rooted into the standard model of particle physics.Comment: jhep style, 22 pages, v2 with updated estimates and extended discussion on parity violation, v3 as published (references updated

    WASTE TREATMENT FACILITY LOCATION FOR HOTEL CHAINS

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    Tourism generates huge amounts of waste. About half of the waste generated by hotels is food and garden bio-waste. This bio-waste can be used to make compost and pellets. In turn, pellets can be used as an absorbent material in composters and as an energy source. We consider the problem of locating composting and pellet-making facilities so that the bio-waste generated by a chain of hotels can be managed at or close to the generation points. An optimization model is applied to locate the facilities and allocate the waste and products, and several scenarios are analysed. The study shows that, depending on the transportation, treatment waste and production management costs, the installation of facilities is profitable for the hotel chain

    Argon K-shell and bound-free emission from OMEGA direct-drive implosion cores

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    We discuss calculations of synthetic spectra for the interpretation and analysis of K-shell and bound-free emission from argon-doped deuterium-filled OMEGA direct-drive implosion cores. The spectra are computed using a model that considers collisional-radiative atomic kinetics, continuum-lowering, detailed Stark-broadened line shapes, line overlapping, and radiation transport effects. The photon energy range covers the moderately optically thick n = 3 → n = 1 and n = 4 → n = 1 line transitions in He- and H-like Ar, their associated satellite lines in Li- and He-like Ar, and several radiative recombination edges. At the high-densities characteristic of implosion cores, the radiative recombination edges substantially shift to lower energies thus overlapping with several line transitions. We discuss the application of the spectra to spectroscopic analysis of doped implosion core

    Observational constraints to boxy/peanut bulge formation time

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    Boxy/peanut bulges are considered to be part of the same stellar structure as bars and both could be linked through the buckling instability. The Milky Way is our closest example. The goal of this letter is determining if the mass assembly of the different components leaves an imprint in their stellar populations allowing to estimate the time of bar formation and its evolution. To this aim we use integral field spectroscopy to derive the stellar age distributions, SADs, along the bar and disc of NGC 6032. The analysis shows clearly different SADs for the different bar areas. There is an underlying old (>=12 Gyr) stellar population for the whole galaxy. The bulge shows star formation happening at all times. The inner bar structure shows stars of ages older than 6 Gyrs with a deficit of younger populations. The outer bar region presents a SAD similar to that of the disc. To interpret our results, we use a generic numerical simulation of a barred galaxy. Thus, we constrain, for the first time, the epoch of bar formation, the buckling instability period and the posterior growth from disc material. We establish that the bar of NGC 6032 is old, formed around 10 Gyr ago while the buckling phase possibly happened around 8 Gyr ago. All these results point towards bars being long-lasting even in the presence of gas.Comment: Accepted for publication in MNRAS Letter

    Near-infrared and optical observations of galactic warps: A common, unexplained feature of most discs

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    Context: Warps occurring in galactic discs have been studied extensively in HI and in the optical, but rarely in the near-infrared (NIR) bands that trace the older stellar populations. Aims: We provide NIR data of nearby edge-on galaxies, combined with optical observations, for direct comparison of the properties of galactic warps as a function of wavelength, and calculate warp curves for each galaxy and obtain the characteristic warp parameters. We discuss these properties as possible constraints to the different mechanisms that have been proposed for the development and persistence of galactic warps. Methods: We observed 20 galaxies that were selected from a statistically complete diameter-limited subsample of edge-on disc galaxies. We used the Cerro Tololo Infrared Imager (CIRIM) at the CTIO 1.5m Ritchey-Chretien telescope to acquire the NIR data. We used the 1.54m Danish and 0.92m Dutch telescopes at the European Southern Observatory's La Silla site for our optical observations. Results: Our results show that 13 of our 20 sample galaxies are warped, with the warp more pronounced in the optical than at NIR wavelengths. In the remaining seven galaxies, no warp is apparent within the limitations of our automated detection method. The transition between the unperturbed inner disc and the outer, warped region is rather abrupt. S0 galaxies exhibit very small or no warps. The magnetic model remains one of a number of interesting formation scenarios.Comment: 16 page

    Observational Evidence of Accretion Disk-Caused Jet Precession in Galactic Nuclei

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    We show that the observational data of extragalactic radio sources tend to support the theoretical relationship between the jet precession period and the optical luminosity of the sources, as predicted by the model in which an accretion disk causes the central black hole to precess.Comment: 13 pages, 1 figure, accepted for publication in ApJ Letter

    Contribution of CD30/CD153 but not of CD27/CD70, CD134/OX40L, or CD137/4-1BBL to the optimal induction of protective immunity to Mycobacterium avium

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    A panel of monoclonal antibodies specific for CD27 ligand (CD70), CD30 ligand (CD153), CD134 ligand (OX40L), and CD137 ligand (4-1BBL) were screened in vivo for their ability to affect the control of Mycobacterium avium infection in C57B1/6 mice. Only the blocking of CD153 led to increased mycobacterial burdens. We then used CD30-deficient mice and found an increase in the proliferation of two strains of M. avium in these mice as compared with control animals. The increased mycobacterial growth was associated with decreased T cell expansion and reduced interferon-gamma (IFN-gamma) responses as a result of reduced polarization of the antigen-specific, IFN-gamma-producing T cells. At late times but not early in infection, the lymphoid cuff surrounding granulomas was depleted in the CD30-deficient animals. This report expands our knowledge about tumor necrosis factor superfamily members involved in the immune responses to mycobacterial infection by identifying CD30-CD153 interactions as required for optimal immune control of M. avium infection
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