976 resultados para pressurized hot water


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In some regions of Brazil, especially where the water is scarce, drinking water is stored in water storage tanks. This practice gives the consumer the guarantee of available water. The water storage conditions such as the exposure to hot weather when the tanks are on rooftops allow the development of microorganisms and microbial biofilms which can deteriorate the water quality and increase the risk to human health [1,2]. This study describes the filamentous fungi (FF) detected in free water and biofilms in drinking water storage tanks in Recife - Pernambuco, Brazil. Five sampling times in triplicate were performed at two distinct points. Colony-forming units (CFU) of FF fungi were determined with 0.45 μm filtration membranes using peptone glucose rose Bengal agar (PGRBA). From the 30 samples analysed a total of 1136 CFU were obtained. The water biofilms were collected from samplers consisting of polyethylene coupons, previously installed in the reservoirs. These coupons were transferred to PGRBA plates and incubated using with the same conditions described for free FF. For the in situ detection of FF in biofilms the Calcofluor White staining technique was used. This procedure demonstrated FF forming biofilms on the surfaces of the coupons. Brazilian legislation does not define limits for FF in drinking water. However considering the potential risk of fungal contamination, the data obtained in this study will contribute to developing future quantitative and qualitative parameters for the presence of fungi in drinking water distribution systems in Brazil.

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Over the years, the Iowa Department of Transportation has established an outstanding network of connector highways across the state of Iowa. Construction and paving of these primary roadways has essentially been completed. Unfortunately, many of these primary highway pavements are reaching their design life and are in need of rehabilitation. The emphasis, therefore, has shifted from the construction of new highways to the maintenance and rehabilitation of existing highways. The Iowa DOT in recent years has become more concerned with preventing the ingress of surface water into the pavement structure. Crack sealing is receiving greater emphasis. Specifications have been modified to require improved low modulus crack and joint sealing materials.

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Teollisessa kromatografiassa kolonnia pyritään kuormittamaan mahdollisimman paljon, jotta saataisiin maksimoitua erotetun komponentin määrä aikayksikköä kohden. Tässä työssä kuormitusta tutkittiin nostamalla syöttöliuoksen, synteettisen melassin, näyteväkevyyttä 80-125 ºC:ssa. Eluenttina oli paineistettu kuumaa vesi ja hartsina vahva Na-muotoinen PS-DVB pohjainen vahva kationinvaihtohartsi. Lämpötilaa nostamalla piikit kapenivat ja tulivat symmetrisemmiksi, erotus nopeutui sekä suola erottui usein paremmin sokereista. Syöttöliuoksen kuiva-ainetta lisättiin asteittain 55 p-% saakka, jolloin ei vielä havaittu ongelmia erotuksessa. Lämpötilassa 125 ºC havaittiin erotuksen aikana kuormituksesta riippumatonta sakkaroosin invertoitumista. Vertailtaessa eri stationäärifaaseja havaittiin Na-muotoisen PS-DVB pohjaisen kationinvaihtohartsin erottavan yleensä sokereita, sokerialkoholeja, oligosakkarideja ja betaiinia lähes poikkeuksetta paremmin alhaisilla pitoisuuksilla kuin neutraalihartsi ja Na-muotoinen zeoliitti. Erottuminen ei yleensä parantunut lämpötilaa nostamalla, mutta piikit kapenivat ja erotus nopeutui. Monosakkaridien erotus huononi 125 ºC:ssa kationinvaihtohartsilla. Tutkittaessa terveysvaikutteisten ksylo-oligosakkaridien soveltuvuutta alikriittiseen erotukseen, niiden havaittiin huomattavasti hydrolysoituvan happamissa olosuhteissa koeputkessa 100 ºC:ssa kahdessa tunnissa. Näytteessä olevien epäpuhtauksien havaittiin katalysoineen hydrolyysiä. Hydrolysoituminen oli hitaampaa neutraaleissa olosuhteissa korotetussa lämpötilassa. Tästä voitiin tehdä johtopäätös, että alikriittiset olosuhteet eivät sovi ksylo-oligosakkaridien erotukseen.

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Hydration is recommended in order to decrease the overload on the cardiovascular system when healthy individuals exercise, mainly in the heat. To date, no criteria have been established for hydration for hypertensive (HY) individuals during exercise in a hot environment. Eight male HY volunteers without another medical problem and 8 normal (NO) subjects (46 ± 3 and 48 ± 1 years; 78.8 ± 2.5 and 79.5 ± 2.8 kg; 171 ± 2 and 167 ± 1 cm; body mass index = 26.8 ± 0.7 and 28.5 ± 0.6 kg/m²; resting systolic (SBP) = 142.5 and 112.5 mmHg and diastolic blood pressure (DBP) = 97.5 and 78.1 mmHg, respectively) exercised for 60 min on a cycle ergometer (40% of VO2peak) with (500 ml 2 h before and 115 ml every 15 min throughout exercise) or without water ingestion, in a hot humid environment (30ºC and 85% humidity). Rectal (Tre) and skin (Tsk) temperatures, heart rate (HR), SBP, DBP, double product (DP), urinary volume (Vu), urine specific gravity (Gu), plasma osmolality (Posm), sweat rate (S R), and hydration level were measured. Data were analyzed using ANOVA in a split plot design, followed by the Newman-Keuls test. There were no differences in Vu, Posm, Gu and S R responses between HY and NO during heat exercise with or without water ingestion but there was a gradual increase in HR (59 and 51%), SBP (18 and 28%), DP (80 and 95%), Tre (1.4 and 1.3%), and Tsk (6 and 3%) in HY and NO, respectively. HY had higher HR (10%), SBP (21%), DBP (20%), DP (34%), and Tsk (1%) than NO during both experimental situations. The exercise-related differences in SBP, DP and Tsk between HY and NO were increased by water ingestion (P < 0.05). The results showed that cardiac work and Tsk during exercise were higher in HY than in NO and the difference between the two groups increased even further with water ingestion. It was concluded that hydration protocol recommended for NO during exercise could induce an abnormal cardiac and thermoregulatory responses for HY individuals without drug therapy.

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An electric system based on renewable energy faces challenges concerning the storage and utilization of energy due to the intermittent and seasonal nature of renewable energy sources. Wind and solar photovoltaic power productions are variable and difficult to predict, and thus electricity storage will be needed in the case of basic power production. Hydrogen’s energetic potential lies in its ability and versatility to store chemical energy, to serve as an energy carrier and as feedstock for various industries. Hydrogen is also used e.g. in the production of biofuels. The amount of energy produced during hydrogen combustion is higher than any other fuel’s on a mass basis with a higher-heating-value of 39.4 kWh/kg. However, even though hydrogen is the most abundant element in the universe, on Earth most hydrogen exists in molecular forms such as water. Therefore, hydrogen must be produced and there are various methods to do so. Today, the majority hydrogen comes from fossil fuels, mainly from steam methane reforming, and only about 4 % of global hydrogen comes from water electrolysis. Combination of electrolytic production of hydrogen from water and supply of renewable energy is attracting more interest due to the sustainability and the increased flexibility of the resulting energy system. The preferred option for intermittent hydrogen storage is pressurization in tanks since at ambient conditions the volumetric energy density of hydrogen is low, and pressurized tanks are efficient and affordable when the cycling rate is high. Pressurized hydrogen enables energy storage in larger capacities compared to battery technologies and additionally the energy can be stored for longer periods of time, on a time scale of months. In this thesis, the thermodynamics and electrochemistry associated with water electrolysis are described. The main water electrolysis technologies are presented with state-of-the-art specifications. Finally, a Power-to-Hydrogen infrastructure design for Lappeenranta University of Technology is presented. Laboratory setup for water electrolysis is specified and factors affecting its commissioning in Finland are presented.

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Abstract In this work, a novel on-line process for production of food-grade emulsions containing oily extracts, i.e. oil-in-water (O/W) emulsions, in only one step is presented. This process has been called ESFE, Emulsions from Supercritical Fluid Extraction. With this process, emulsions containing supercritical fluid extracts can be obtained directly from plant materials. The aim in the conception of this process is to propose a new rapid way to obtain emulsions from supercritical fluid extracts. Nowadays the conventional emulsion formulation method is a two-step procedure, i.e. first supercritical fluid extraction for obtaining an extract; secondly emulsion formulation using another device. Other variation of the process was tested and successfully validated originating a new acronymed process: EPFE (Emulsions from Pressurized Fluid Extractions). Both processes exploit the supercritical CO2-essential oils miscibility, in addition, EPFE process exploits the emulsification properties of saponin-rich pressurized aqueous plant extracts. The feasibility of this latter process was demonstrated using Pfaffia glomerata roots as source of saponin-rich extract, water as extracting solvent and clove essential oil, directly extracted using supercritical CO2, as a model dispersed phase. In addition, examples of pressurized fluid-based coupled processes applied for adding value to food bioactive compounds developed in the past five years are reviewed.

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The objective of the present study is to elucidate the hydrological conditions of the shelf waters along the southern half or the west coast of India and their relation to the sooplankton bionase and pelagic fish resources. Data from six hydrography-plankton sections worked during the 1972-75 period of cape camerin. Quilon. cochin. Kasaragod. Karwar and kotnagiri formed the basis of the present study.Stations were fixed along the transects 10 nautical miles apart. Starting with the first station at around 15 metre depth and were usually occupied 5 to 8 times in an year at an interval of about 6 weeks. Data relating to oil sardines and macherel fisheries were availed from published information relating to the period mainly of the Central Marine fisheries Research Institute. The range of different parameters namely temperature. salinity. density and dissolved oxygen at different depths and their sloping features against the coast are discussed. Three seasons. namely south-west monsoon (summer monsoon). north-east monsoon (winter monsoon) and hot weather season are designated and data of the core months of each of these seasons considered in the study.

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A strong climatic warming is currently observed in the Caucasus mountains, which has profound impact on runoff generation in the glaciated Glavny (Main) Range and on water availability in the whole region. To assess future changes in the hydrological cycle, the output of a general circulation model was downscaled statistically. For the 21st century, a further warming by 4–7 °C and a slight precipitation increase is predicted. Measured and simulated meteorological variables were used as input into a runoff model to transfer climate signals into a hydrological response under both present and future climate forcings. Runoff scenarios for the mid and the end of the 21st century were generated for different steps of deglaciation. The results show a satisfactory model performance for periods with observed runoff. Future water availability strongly depends on the velocity of glacier retreat. In a first phase, a surplus of water will increase flood risk in hot years and after continuing glacier reduction, annual runoff will again approximate current values. However, the seasonal distribution of streamflow will change towards runoff increase in spring and lower flows in summer.

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We present an analysis of seven primary transit observations of the hot Neptune GJ436b at 3.6, 4.5, and 8 μm obtained with the Infrared Array Camera on the Spitzer Space Telescope. After correcting for systematic effects, we fitted the light curves using the Markov Chain Monte Carlo technique. Combining these new data with the EPOXI, Hubble Space Telescope, and ground-based V, I, H, and Ks published observations, the range 0.5-10 μm can be covered. Due to the low level of activity of GJ436, the effect of starspots on the combination of transits at different epochs is negligible at the accuracy of the data set. Representative climate models were calculated by using a three-dimensional, pseudospectral general circulation model with idealized thermal forcing. Simulated transit spectra of GJ436b were generated using line-by-line radiative transfer models including the opacities of the molecular species expected to be present in such a planetary atmosphere. A new, ab-initio-calculated, line list for hot ammonia has been used for the first time. The photometric data observed at multiple wavelengths can be interpreted with methane being the dominant absorption after molecular hydrogen, possibly with minor contributions from ammonia, water, and other molecules. No clear evidence of carbon monoxide and carbon dioxide is found from transit photometry. We discuss this result in the light of a recent paper where photochemical disequilibrium is hypothesized to interpret secondary transit photometric data. We show that the emission photometric data are not incompatible with the presence of abundant methane, but further spectroscopic data are desirable to confirm this scenario.

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Hot rolling process is heat input process. The heat energy in hot rolled steel coils can be utilized. At SSAB Strip Product Borlänge when the hot rolled steel coils came out of the hot rolling mill they are at the temperature range of 500°C to 800°C. Heat energy contained by the one hot rolled steel coil is about 1981Kwh whereas the total heat energy for the year 2008 is 230 GWh/year.The potential of heat is too much but the heat dissipation rate is too slow. Different factors on which heat dissipation rate depends are discussed.Three suggestions are proposed to collect the waste heat from hot rolled steel coils.The 2nd proposal in which water basin is suggested would help not only to collect the waste heat but to decrease in the cooling time.

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The fuel cell is an emerging cogeneration technology that has been applied successfully in Japan, the USA and some countries in the European Union. This system performs direct conversion of the chemical energy of the oxidation of hydrogen from fuel with atmospheric oxygen into direct current electricity and waste heat via an electrochemical process relying on the use of different electrolytes (phosphoric acid, molten carbonate and solid oxide, depending on operating temperature). This technology permits the recovery of waste heat, available from 200 degreesC up to 1000 degreesC depending on the electrolyte technology, which can be used in the production of steam, hot or cold water, or hot or cold air, depending on the associated recuperation equipment. In this paper, an energy, exergy and economic analysis of a fuel cell cogeneration system (FCCS) is presented. The FCCS is applied in a segment of the tertiary sector to show that it is a feasible alternative for rational decentralized energy production under Brazilian conditions. The technoeconomic analysis shows a global efficiency or fuel utilization efficiency of 86%. Analysis shows that the exergy losses in the fuel cell unit and the absorption refrigeration system are significant. Furthermore, the payback period estimated is about 3 and 5 years for investments in fuel cells of 1000 and 1500 US$/kW, respectively. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

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This study was conducted to evaluate the morphologic modifications in tissues of the fruit and seed of the crambe (Crambe abyssinica Hochst. Ex R.E. Fr.) after drying at different temperatures. Fruits with a water content of 0.38 kg water/kg dry matter were harvested and manually homogenized. Drying was accomplished at 35, 45, 60, 75, and 90°C and at 21,9,7,5, and 2% relative humidity, respectively. After drying, the structure of the pericarp and tegument of the seed were evaluated and the embryo was removed from the fruit/seed for morphological analysis (structural and ultrastructural and the histolocalization of reserve substances). Drying at different temperatures did not affect the cellular structure of the tissues composing the pericarp of the fruits, but it disorganized the structure of the seed tegument. The cells of the tegument and cotyledons presented a contraction in their volumes. The lowest contractions in the cellular volumes of both the tegument and cotyledons occurred after drying at 35 and 45°C. The cytoplasm of the cotyledon cells contains oil drops and the protein bodies contain protein granules and starch grains. There were no changes in the cellular walls of the embryos of the fruits dried at different temperatures; however, ungluing of the medium lamella occurred. This damage occurred with greater intensity after drying at temperatures above 60°C. The form of the oil drops in the cytoplasm of the cotyledon cells was altered after drying. At temperatures above 60°C, the drops broke up and coalesced. After drying at 45 and 60°C, the form of some protein bodies was altered, whereas at 75 and 90°C coalescence of the protein bodies occurred in some cells. It was concluded that the identified alterations can affect the physiologic quality of crambe seeds. © 2013 Copyright Taylor and Francis Group, LLC.

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Cellulase, an enzymatic complex that synergically promotes the degradation of cellulose to glucose and cellobiose, free or adsorbed onto Si/SiO(2) wafers at 60 degrees C has been employed as catalyst in the hydrolysis of microcrystalline cellulose (Avicel), microcrystalline cellulose pre-treated with hot phosphoric acid (CP), cotton cellulose (CC) and eucalyptus cellulose (EC). The physical characteristics such as index of crystallinity (I(C)), degree of polymerization (DP) and water sorption values were determined for all samples. The largest conversion rates of cellulose into the above-mentioned products using free cellulase were observed for samples with the largest water sorption values; conversion rates showed no correlation with either IC or DP of the biopolymer. Cellulose with large water sorption value possesses large pore volumes, hence higher accessibility. The catalytic efficiency of immobilized cellulase could not be correlated with the physical characteristics of cellulose samples. The hydrolysis rates of the same cellulose samples with immobilized cellulase were lower than those by the free enzyme, due to the diffusion barrier (biopolymer chains approaching to the immobilized enzyme) and less effective contact between the enzyme active site and its substrate. Immobilized cellulase, unlike its free counterpart, can be recycled at least six times without loss of catalytic activity, leading to higher overall cellulose conversion. (C) 2011 Elsevier B.V. All rights reserved.

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La crescente attenzione verso un utilizzo attento, sostenibile ed economicamente efficiente della risorsa idrica rende di primaria importanza il tema delle perdite idriche e della gestione efficiente dei sistemi idrici. La richiesta di controlli dell’uso dell’acqua è stata avanzata a livello mondiale. Il problema delle perdite idriche nei Paesi industrializzati è stato così affrontato con specifiche normative e procedure di best practice gestionale per avanzare una valutazione delle perdite idriche e una limitazione degli sprechi e degli usi impropri. In quest’ambito, la pressione gioca un ruolo fondamentale nella regolazione delle perdite reali. La regolazione delle pressioni nelle diverse ore del giorno consente, infatti, di poter agire su queste ultime perdite, che aumentano all’aumentare della pressione secondo una cosiddetta legge di potenza. La motivazione della presente tesi è originata dalla necessità di quantificare il livello di perdita idrica in un sistema acquedottistico in relazione alla pressione all’interno del sistema stesso. Per avere una stima realistica che vada al di là della legge della foronomia, si vuole valutare l’influenza della deformabilità della condotta in pressione fessurata sull’entità delle perdite idriche, con particolare attenzione alle fessurazioni di tipo longitudinale. Tale studio è condotto tramite l’introduzione di un semplice modello di trave alla Winkler grazie al quale, attraverso un’analisi elastica, si descrive il comportamento di una generica condotta fessurata longitudinalmente e si valuta la quantità d’acqua perduta. I risultati ottenuti in condizioni specifiche della condotta (tipo di materiale, caratteristiche geometriche dei tubi e delle fessure, etc.) e mediante l’inserimento di opportuni parametri nel modello, calibrati sui risultati forniti da una raffinata modellazione tridimensionale agli elementi finiti delle medesime condotte, verranno poi confrontati con i risultati di alcune campagne sperimentali. Gli obiettivi del presente lavoro sono, quindi, la descrizione e la valutazione del modello di trave introdotto, per stabilire se esso, nonostante la sua semplicità, sia effettivamente in grado di riprodurre, in maniera realistica, la situazione che si potrebbe verificare nel caso di tubo fessurato longitudinalmente e di fornire risultati attendibili per lo studio delle perdite idriche. Nella prima parte verrà approfondito il problema della perdite idriche. Nella seconda parte si illustrerà il semplice modello di trave su suolo elastico adottato per l’analisi delle condotte in pressione fessurate, dopo alcuni cenni teorici ai quali si è fatto riferimento per la realizzazione del modello stesso. Successivamente, nella terza parte, si procederà alla calibrazione del modello, tramite il confronto con i risultati forniti da un’analisi tridimensionale agli elementi finiti. Infine nella quarta parte verrà ricavata la relazione flusso-pressione con particolare attenzione all’esponente di perdita, il cui valore risulterà superiore a quello predetto dalla teoria della foronomia, e verrà verificata l’effettiva validità del modello tramite un confronto con i risultati sperimentali di cui è stata fatta menzione in precedenza.

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Free-living amoebae (FLA) belonging to Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris, and Sappinia pedata are known to cause infections in humans and animals leading to severe brain pathologies. Worldwide, warm aquatic environments have been found to be suitable habitats for pathogenic FLA. The present study reports on screening for potentially pathogenic FLA in four hot spring resorts in Switzerland. Water samples were taken from water filtration units and from the pools, respectively. Amoebae isolated from samples taken during, or before, the filtration process were demonstrated to be morphologically and phylogenetically related to Stenoamoeba sp., Hartmannella vermiformis, Echinamoeba exundans, and Acanthamoeba healyi. With regard to the swimming pools, FLA were isolated only in one resort, and the isolate was identified as non-pathogenic and as related to E. exundans. Further investigations showed that the isolates morphologically and phylogenetically related to A. healyi displayed a pronounced thermotolerance, and exhibited a marked in vitro cytotoxicity upon 5-day exposure to murine L929 fibroblasts. Experimental intranasal infection of Rag2-immunodeficient mice with these isolates led to severe brain pathologies, and viable trophozoites were isolated from the nasal mucosa, brain tissue, and lungs post mortem. In summary, isolates related to A. healyi were suggestive of being potentially pathogenic to immunocompromised persons. However, the presence of these isolates was limited to the filtration units, and an effective threat for health can therefore be excluded.