935 resultados para Water distribution systems


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Water is an economic, strategic and social valuable resource of the utmost importance to society. This renewable natural resource is increasingly scarce with the growing of populations, industries and agriculture, in addition to the pollution surface and underground water and the waste have aggravated this situation. Investments in the sector of water resources so that this resource meets in quantity and quality the demand from its multiple uses, represent a significant portion of national and regional budgets. Therefore, the use of alternative sources of water capture can reduce the pressure on conventional public water supply systems. In this work was designed and executed a rain water collection system to a residence in the city of Barueri (SP), which can be applied to other residences. In this system, the rooftop of the residence was used as the waterproof and capture area. The gutter and the PVC conductors were used for driving the water to two connected reservoirs. The stored water was designed to address activities that are not potable, such as washing clothes and external areas and garden irrigation. The system showed economic viability, with 34-month return of investment time, wherein after that period, in addition to environmental and social benefits derived from the implementation of the project, the economy made with the payment of public supply rates should be considered. This rainwater capture system is inexpensive and uses materials available in the market. Therefore, its application to a greater number of households should be encouraged as a measure of sustainable water management

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Over the past two years, Brazil has been facing a major water crisis in its history and the state of Sao Paulo is the one that has been going through worst difficulties. In this scenario, all water users should do everything possible so that the consumption of water resources is carried out in a sustainable manner. In this context, the companies responsible for the public water supply must increase the efficiency of water resource management. It is indispensable combating losses in the public supply system. When there is a non-visible leak in a pipe, the wastewater volume can be high, but in this case, the water returns to nature and continues to participate in the hydrological cycle. The economic loss corresponds to the value added to the product water, which includes the intrinsic costs of exploration, processing and distribution. This damage results in a reduced availability of financial resources of sanitation companies to invest in environmentally friendly solutions. This study aimed to diagnose the water distribution system in the city of Guaratinguetá (SP), held by the Companhia de Serviços de Água, Esgoto e Resíduos de Guaratinguetá (SAEG), to propose measures to combat water loss. Among the proposed measures, there is the monitoring of losses, planning for replacement of old pipes and company awareness as a whole in relation to combat water losses

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The chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate (TCPO) and bis(2-nitrophenyl)oxalate (2-NPO) with hydrogen peroxide in acetonitrile/water micellar systems (anionic, cationic, and non-ionic) and gamma-cyclodextrin were studied in the presence of fluoranthene or 9,10-diphenylanthracene, imidazole, and two buffer solutions, HTRIS+/TRIS and H2PO4-/HPO42-. The relative chemiluminenscence (CL) intensity is higher in the presence of the cationic (DDAB, CTAC, DODAC, and OTAC), anionic (SDS), and non-ionic (Tween 80) surfactants. In the presence of some non-ionic surfactants (Brij 35, Brij 76, and Tween 20), the CL intensity was partially quenched compared with the reaction with no surfactant. The sensitivity for hydrogen peroxide determination in the range 0.01 x 10(-4) to 1.0 x 10(-4) mol L-1, considering the slope of the calibration curves (maximum peak height of CL vs. concentration), improved with the introduction of DDAH, CTAB, and SDS in HTRIS+/TRIS buffer.

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Supercritical carbon dioxide is a promising green-chemistry solvent for many enzyme-catalyzed chemical reactions, yet the striking stability of some enzymes in such unconventional environments is not well understood. Here, we investigate the stabilization of the Candida antarctica Lipase B (CALB) in supercritical carbon dioxide-water biphasic systems using molecular dynamics simulations. The preservation of the enzyme structure and optimal activity depend on the presence of small amounts of water in the supercritical dispersing medium. When the protein is at least partially hydrated, water molecules bind to specific sites on the enzyme surface and prevent carbon dioxide from penetrating its catalytic core. Strikingly, water and supercritical carbon dioxide cover the protein surface quite heterogeneously. In the first solvation layer, the hydrophilic residues at the surface of the protein are able to pin down patches of water, whereas carbon dioxide solvates preferentially hydrophobic surface residues. In the outer solvation shells, water molecules tend to cluster predominantly on top of the larger water patches of the first solvation layer instead of spreading evenly around the remainder of the protein surface. For CALB, this exposes the substrate-binding region of the enzyme to carbon dioxide, possibly facilitating diffusion of nonpolar substrates into the catalytic funnel. Therefore, by means of microheterogeneous solvation, enhanced accessibility of hydrophobic substrates to the active site can be achieved, while preserving the functional structure of the enzyme. Our results provide a molecular picture on the nature of the stability of proteins in nonaqueous media.

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[ES] El conocimiento de criterios que ayuden a priorizar el uso del agua es fundamental para garantizar su uso sostenible. En las zonas semiáridas, el abandono de la actividad agrícola puede estar motivado por la escasez de agua y por problemas de mercado de las especies tradicionalmente cultivadas. Por otro lado, la actividad ganadera, suele estar limitada por la escasez de forrajes. La disponibilidad de agua regenerada a un precio razonable podría evitar su vertido y contrarrestar la degradación de suelos abandonados, potenciando la producción de especies forrajeras rentables, contribuyendo así a la ganadería sostenible. Para ello se requiere optimizar la distribución del agua considerando varios criterios simultáneamente

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Le reti di distribuzione idrica conservano un ruolo importante ed irrinunciabile nella sicurezza antincendio, ma diversi fattori sul piano normativo e strutturale limitano la loro potenzialità  nelle fasi di estinzione dell'incendio. Ma in che modo si è evoluta in Italia negli ultimi anni la lotta all'incendio? E' ormai noto che non esistono incendi standard, quelli per i quali è possibile definire procedure d'intervento e modalità  di estinzione; non è quindi banale identificare le portate antincendio necessarie (Needed Fire Flow) e il tempo per il quale esse devono essere garantite. In certi contesti è possibile ipotizzare un certo standard d'incendio ma ciò presuppone che edifici, strutture e tutto ciò che è sottoposto ad incendio, possano essere considerati fabbricati a "regola d'arte", ovvero realizzati attraverso procedure esecutive aventi standard di qualità  certificata. Ciò è stato affrontato nei criteri di realizzazione delle nuove costruzioni, ma le vecchie costruzioni, soprattutto gli edifici presenti nei centri storici, sono evidentemente più vulnerabili e sfuggono alla possibilità  di identificare affidabili valori del NFF. Il quadro che si presenta coinvolge quindi carenze normative, contesti urbani con differente vulnerabilità  e una sostanziale disomogeneità  prestazionale delle reti di distribuzione idrica presenti nel territorio nazionale, legata non solo alla disponibilità  idrica ma, anche e soprattutto, alla conformazione della rete, ai livelli di pressione ed alla specifica capacità della rete nel sostenere incrementi di flusso dovuto al prelievo dagli idranti stradali. La scarsa conoscenza di questi aspetti, piuttosto che tradursi in miglioramenti della rete idrica e della sua efficienza ai fini antincendio, ha portato nel tempo ad adottare soluzioni alternative che agiscono principalmente sulle modalità operative di utilizzo dei mezzi dei VV.F. e sul fronte dei dispositivi antincendio privati, quali una migliore protezione passiva, legata all'uso di materiali la cui risposta all'incendio fosse la minore possibile, e protezioni attive alternative, quali impianti sprinkler, di tipo aerosol o misti. Rimangono tutte le problematiche legate alla caratterizzazione nell'area urbanizzata in termini di risposta al prelievo per incendio dagli idranti pubblici sui quali la normativa vigente non impone regole circa le prestazioni e la loro dislocazione sul territorio. Questa incertezza spesso si traduce in un maggiore dispiego di mezzi rispetto all'entità dell'incendio ed ad una scarsa possibilità  di ottimizzare l'allocazione delle unità  operative dei VV.F., con un evidente incremento del rischio nel caso in cui si verifichino più eventi di incendio contemporaneamente. La simulazione numerica avanzata, su modelli opportunamente calibrati delle reti di distribuzione, può consentire una maggiore comprensione quantitativa del livello di sicurezza antincendio offerto da una rete di distribuzione idrica.

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Hochgeladene semiflexible kationische und anionische Polyelektrolyte wurden mit niedermolekularen Tensiden zu Polyelektrolyt-Tensid-Komplexen (PETK) umgesetzt und in organischen Lösungsmitteln mit Streumethoden und Rasterkraftmikroskopie charakterisiert. Die synthetisierten PETK wurden anschließend, mit dem Ziel einer strukturkontrollierten Komplexbildung, für die Bildung von Interpolyelektrolytkomplexen (IPEK) in organischen Lösungsmitteln verwendet und anhand ihres Komplexbildungsverhaltens mit wässrigen Systemen verglichen. Die Umsetzung von zylindrischen Polymerbürsten mit Poly(styrolsulfonat)-, bzw. Poly(2-vinylpyridinium)-Seitenketten mit entgegengesetzt geladenen Tensiden verlief, trotz einer Graftingdichte von eins, quantitativ. Mit Streumethoden konnte gezeigt werden, dass die gebildeten PETK in Lösung als molekulare Zylinder vorliegen. Die Synthese von pUC19-DNA-Tensidkomplexen (DNA-TK), die sich in Alkoholen gut lösen, ist nur in stark basischer Lösung gelungen. Während der Charakterisierung der DNA-TK mit Streumethoden zeigte sich eine starke Abhängigkeit des Trägheitsradius von dem Verhältnis DNA-/Salz+. Die Bildung von IPEK aus hochgeladenen Polyelektrolyt-Bürsten bzw. PETK-Bürsten wurde an verschiedenen Beispielen in Wasser und DMF durchgeführt und mit Streumethoden verfolgt. Alle Systeme zeigten ein zu der IPEK-Bildung von linearen Polyelektrolyten analoges Komplexbildungsverhalten. Bei der Komplexierung von Poly(styrolsulfonat)-Bürsten-Tensidkomplexen mit kommerziellen Polyamidoamin-G5-Dendrimeren (PAMAM) oder Poly(ethylenoxid) modifizierten Poly(ethylenimin)-Bürsten hingegen wurden über den gesamten Gewichtsbruchbereich mit Streumethoden und AFM zylindrische Aggregate gefunden, die den Dimensionen der Poly(styrolsulfonat)-Bürsten-Tensidkomplexe entsprechen. Durch statistische Höhenanalyse der AFM-Bilder wurde ein linearer Zusammenhang zwischen der Komplexhöhe und dem Gewichtsbruch an PAMAM, bzw. PEI-PEO gefunden, der auf die Zunahme der Molmasse der Komplexe durch Wachstum entlang des Zylinderdurchmessers hindeutet. Die Bildung von Aggregaten, mit mehr als einem Polyanion, wurde nicht beobachtet.

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Un sistema di distribuzione idropotabile (Water Distribution Network -WDN), data la sua complessità strutturale e funzionale, per l' ordinario esercizio richiede elevati quantitativi di energia. L'attuale trend tecnico/scientifico incoraggia la loro gestione e progettazione nell'ottica di un generale risparmio di energia che, oltre ad un indiscusso vantaggio economico, implica sopratutto una razionalizzazione dell'impiego di risorsa idrica. Questo è il contesto scientifico/culturale in cui il presente elaborato si colloca. Nello specifico, ci si propone la caratterizzazione energetica di la rete di distribuzione idrica Cabrera_network.(rivisitazione della rete presentata da E.Cabrera e M.Pardo nel loro studio del 2010) . Si sono quindi qualificati i legami tra i consumi energetici ed aspetti, quali: dimensionamento dei condotti, perdite idriche, tipologia di pompa centrifuga sfruttata e livello idrico massimo del serbatoio di compenso. Ciò è stato esplicato in due fasi di analisi. In una primo momento, si sono impiegati strumenti classi quali il simulatore idraulico Epanet2 e i fogli di calcolo Excel. In un secondo momento, il problema dell'ottimizzazione energetica della rete è stato risolto a mezzo l'algoritmo euristico GHEST. Al di là delle specifiche conclusioni, cui si rinvia, l'elaborato consente di cogliere un più generale profilo di ordine metodologico: l'importanza di una visione d'insieme del problema energetico in un sistema di distribuzione idropotabile, dalla quale, nel caso di specie, emerge che la scelta più ragionevole, al fine dell'ottimizzazione energetica, consiste nell'individuazione del più idoneo modello di pompa alimentante la rete. Per poi, data l'onere progettuale e applicativo che comporta, provvedere al reinvestimento dei capitali risparmiati in attività volte alla riduzione delle perdite idriche. Sono questi infatti, i due aspetti che più incidono sui consumi energetici nel caso di studio.

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Biological systems are complex and highly organized architectures governed by noncovalent interactions, which are responsible for molecular recognition, self-assembly, self-organization, adaptation and evolution processes. These systems provided the inspiration for the development of supramolecular chemistry, that aimed at the design of artificial multicomponent molecular assemblies, namely supramolecular systems, properly designed to perform different operations: each constituting unit performs a single act, whereas the entire supramolecular system is able to execute a more complex function, resulting from the cooperation of the constituting components. Supramolecular chemistry deals with the development of molecular systems able to mimic naturally occurring events, for example complexation and self-assembly through the establishment of noncovalent interactions. Moreover, the application of external stimuli, such as light, allows to perform these operations in a time- and space-controlled manner. These systems can interact with biological systems and, thus, can be applied for bioimaging, therapeutic and drug delivery purposes. In this work the study of biocompatible supramolecular species able to interact with light is presented. The first part deals with the photophysical, photochemical and electrochemical characterization of water-soluble blue emitting triazoloquinolinium and triazolopyridinium salts. Moreover, their interaction with DNA has been explored, in the perspective of developing water-soluble systems for bioimaging applications. In the second part, the effect exerted by the presence of azobenzene-bearing supramolecular species in liposomes, inserted both in the phospholipid bilayer and in the in the aqueous core of vesicles has been studied, in order to develop systems able to deliver small molecules and ions in a photocontrolled manner. Moreover, the versatility of azobenzene and its broad range of applications have been highlighted, since conjugated oligoazobenzene derivatives proved not to be adequate to be inserted in the phospholipid bilayer of liposomes, but their electrochemical properties made them interesting candidates as electron acceptor materials for photovoltaic applications.

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This study aims at a comprehensive understanding of the effects of aerosol-cloud interactions and their effects on cloud properties and climate using the chemistry-climate model EMAC. In this study, CCN activation is regarded as the dominant driver in aerosol-cloud feedback loops in warm clouds. The CCN activation is calculated prognostically using two different cloud droplet nucleation parameterizations, the STN and HYB CDN schemes. Both CDN schemes account for size and chemistry effects on the droplet formation based on the same aerosol properties. The calculation of the solute effect (hygroscopicity) is the main difference between the CDN schemes. The kappa-method is for the first time incorporated into Abdul-Razzak and Ghan activation scheme (ARG) to calculate hygroscopicity and critical supersaturation of aerosols (HYB), and the performance of the modied scheme is compared with the osmotic coefficient model (STN), which is the standard in the ARG scheme. Reference simulations (REF) with the prescribed cloud droplet number concentration have also been carried out in order to understand the effects of aerosol-cloud feedbacks. In addition, since the calculated cloud coverage is an important determinant of cloud radiative effects and is influencing the nucleation process two cloud cover parameterizations (i.e., a relative humidity threshold; RH-CLC and a statistical cloud cover scheme; ST-CLC) have been examined together with the CDN schemes, and their effects on the simulated cloud properties and relevant climate parameters have been investigated. The distinct cloud droplet spectra show strong sensitivity to aerosol composition effects on cloud droplet formation in all particle sizes, especially for the Aitken mode. As Aitken particles are the major component of the total aerosol number concentration and CCN, and are most sensitive to aerosol chemical composition effect (solute effect) on droplet formation, the activation of Aitken particles strongly contribute to total cloud droplet formation and thereby providing different cloud droplet spectra. These different spectra influence cloud structure, cloud properties, and climate, and show regionally varying sensitivity to meteorological and geographical condition as well as the spatiotemporal aerosol properties (i.e., particle size, number, and composition). The changes responding to different CDN schemes are more pronounced at lower altitudes than higher altitudes. Among regions, the subarctic regions show the strongest changes, as the lower surface temperature amplifies the effects of the activated aerosols; in contrast, the Sahara desert, where is an extremely dry area, is less influenced by changes in CCN number concentration. The aerosol-cloud coupling effects have been examined by comparing the prognostic CDN simulations (STN, HYB) with the reference simulation (REF). Most pronounced effects are found in the cloud droplet number concentration, cloud water distribution, and cloud radiative effect. The aerosol-cloud coupling generally increases cloud droplet number concentration; this decreases the efficiency of the formation of weak stratiform precipitation, and increases the cloud water loading. These large-scale changes lead to larger cloud cover and longer cloud lifetime, and contribute to high optical thickness and strong cloud cooling effects. This cools the Earth's surface, increases atmospheric stability, and reduces convective activity. These changes corresponding to aerosol-cloud feedbacks are also differently simulated depending on the cloud cover scheme. The ST-CLC scheme is more sensitive to aerosol-cloud coupling, since this scheme uses a tighter linkage of local dynamics and cloud water distributions in cloud formation process than the RH-CLC scheme. For the calculated total cloud cover, the RH-CLC scheme simulates relatively similar pattern to observations than the ST-CLC scheme does, but the overall properties (e.g., total cloud cover, cloud water content) in the RH simulations are overestimated, particularly over ocean. This is mainly originated from the difference in simulated skewness in each scheme: the RH simulations calculate negatively skewed distributions of cloud cover and relevant cloud water, which is similar to that of the observations, while the ST simulations yield positively skewed distributions resulting in lower mean values than the RH-CLC scheme does. The underestimation of total cloud cover over ocean, particularly over the intertropical convergence zone (ITCZ) relates to systematic defficiency of the prognostic calculation of skewness in the current set-ups of the ST-CLC scheme.rnOverall, the current EMAC model set-ups perform better over continents for all combinations of the cloud droplet nucleation and cloud cover schemes. To consider aerosol-cloud feedbacks, the HYB scheme is a better method for predicting cloud and climate parameters for both cloud cover schemes than the STN scheme. The RH-CLC scheme offers a better simulation of total cloud cover and the relevant parameters with the HYB scheme and single-moment microphysics (REF) than the ST-CLC does, but is not very sensitive to aerosol-cloud interactions.

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Automatischen Sortiersysteme (Sorter) besitzen in der Intralogistik eine große Bedeutung. Sorter erreichen eine ausdauernd hohe Sortierleistung bei gleichzeitig geringer Fehlsortierrate und bilden deshalb oft den zentralen Baustein in Materialflusssystemen mit hoher Umschlagsrate. Distributionszentren mit Lager und Kommissionierfunktion sind typische Vertreter solcher Materialflusssysteme. Ein Sorter besteht aus den Subsystemen Einschleusung, Verteilförderer und Endstellen. Die folgenden Betrachtungen fokussieren auf ein Sortermodell mit einem Verteilförderer in Ringstruktur und einer Einzelplatzbelegung. Auf jedem Platz kann genau ein Gut transportiert werden. Der Verteilförderer besitzt somit eine feste Transportkapazität. Derartige Förderer werden in der Regel als Kippschalen- oder Quergurt-Sorter ausgeführt. Die theoretische Sortierleistung für diesen Sortertyp kann aus Fahrgeschwindigkeit und Transportplatzabstand bestimmt werden. Diese Systemleistung wird im praktischen Betrieb kaum erreicht. Verschiedene Faktoren im Einschleusbereich und im Ausschleusbereich führen zu einer Leistungsminderung. Betrachtungen zur Bestimmung der mittleren Warteschlangenlänge im Einschleusbereich sowie zur Ermittlung des Rundläuferanteils auf dem Verteilförderer werden im folgenden Beitrag vorgestellt. Diesem Beitrag liegt ein Forschungsvorhaben zugrunde, das aus Mitteln des Bundesministeriums für Wirtschaft und Technologie (BMWi) über die Arbeitsgemeinschaft industrieller Forschungsvereinigungen "Otto von Guericke" (AiF) gefördert und im Auftrage der Bundesvereinigung Logistik e.V. (BVL) ausgeführt wurde.

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This report presents the proceedings of the Biochemical Engineering Symposium held at Kansas State University, April 28, 1973. Since a number of the contributions will be published in detail elsewhere, only brief summaries of each contribution are included here. Requests for additional information on projects conducted at The University of Nebraska should be directed to Dr. Peter J. Reilly, and those at Kansas State University to the editors. ContentsKenneth J. Jacobson, Andrew H.C. Chan, and Raymond C. Eliason, "Properties and Utilization of Small Particulates in Cattle Manure" Cady R. Engler and James S. Yohn, "Protein from Manure" Robert J. Williams, "Kinetics of Sucrose Inversion Using Invertase Immobilized on Hollow Fibers of Cellulose Acetate" David F. Aldis and Thomas A. Carlisle, "Study of a Triiodide-Resin Complex Disinfection System" John C. Heydweiller, "Modeling and Analysis of Symbiotic Growth" Kenneth J. Jacobson, "Synchronized Growth of the Blue Green Alga Microcystis aeruginosa" Clarence C. Y. Ron arui Lincoln L. S. Yang, "Computer Modeling of the Reductive Pentose Phosphate Cycle" Ming-ching T. Kuo, "Application of a Parallel Biochemical Oxidation Kinetic Model to the Design of an Activated Sludge System Including a Primary Clarifier" Prakash N. Mishra, "Optimal Synthesis of Water Renovation Systems"

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The evolution of pharmaceutical care is identified through a complete review of the literature published in the American Journal of Health-System Pharmacy, the sole comprehensive publication of institutional pharmacy practice. The evolution is categorized according to characteristics of structure (organizational structure, the role of the pharmacist), process (drug delivery systems, formulary management, acquiring drug products, methods to impact drug therapy decisions), and outcomes (cost of drug delivery, cost of drug acquisition and use, improved safety, improved health outcomes) recorded from the 1950s through the 1990s. While significant progress has been made in implementing basic drug distribution systems, levels of pharmacy involvement with direct patient care is still limited.^ A new practice framework suggests enhanced direct patient care involvement through increase in the efficiency and effectiveness of traditional pharmacy services. Recommendations advance internal and external organizational structure relationships that position pharmacists to fully use their unique skills and knowledge to impact drug therapy decisions and outcomes. Specific strategies facilitate expansion of the breadth and scope of each process component in order to expand the depth of integration of pharmacy and pharmaceutical care within the broad healthcare environment. Economic evaluation methods formally evaluate the impact of both operational and clinical interventions.^ Outcome measurements include specific recommendations and methods to increase efficiency of drug acquisition, emphasizing pharmacists' roles that impact physician prescribing decisions. Effectiveness measures include those that improve safety of drug distribution systems, decrease the potential of adverse drug therapy events, and demonstrate that pharmaceutical care can significantly contribute to improvement in overall health status.^ The implementation of the new framework is modeled on a case study at the M.D. Anderson Cancer Center. The implementation of several new drug distribution methods facilitated the redeployment of personnel from distributive functions to direct patient care activities with significant personnel and drug cost reduction. A cost-benefit analysis illustrates that framework process enhancements produced a benefit-to-cost ratio of 7.9. In addition, measures of effectiveness demonstrated significant levels of safety and enhanced drug therapy outcomes. ^