Search results for "VOLUME"

showing 10 items of 1932 documents

(S)legati (d)al lavoro. Adulti giovani e occupazione tra ricomposizione e frammentazione sociale

2005

Fra i cambiamenti più rilevanti in atto nel mondo del lavoro vi è certamente quello riguardante la diversa accezione che ha assunto l’identità professionale. In presenza di una accentuata volubilità e di una difficile definzione dell’identità professionale – spesso divisa fra molte occupazioni svolte in luoghi e in momenti della propria vita e della giornata diversi – il bisogno di ricomposizione che caratterizza la frammentata società contemporanea e che si declina nei diversi ambiti istituzionali sembra assumere nel lavoro connotazioni assolutamente specifiche che meritano particolare attenzione. Il volume risultato dell’approfondimento di una ricerca condotta in Italia nel 2004 da dieci sedi universitarie e riguardante i percorsi di ricomposizione sociale degli adulti-giovani intende offrire un’analisi dei cambiamenti determinati dal differente modo in cui si declina per questa fascia di età la dimensione lavorativa. Il lavoro ci si è chiesti può essere considerato un ambito di ricomposizione nella frammentata vita degli adulti giovani? Attraverso l’analisi quali-quantitativa di diverso materiale empirico si è inteso scandagliare nel rapporto esistente fra lavoro progetto biografico e formazione dell’identità professionale in un periodo in cui la difficile “transizione alla vita adulta” assume sempre più i caratteri della dilazione continuata e in cui “ricomporre la vita” diventa anche per gli adulti giovani sempre più difficile.
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Adaptive PI Control of Bottom Hole Pressure during Oil Well Drilling

2018

Abstract In this paper, we studied the bottom hole pressure (BHP) control in an oil well during drilling. Today marginal wells with narrow pressure windows are frequently being drilled. This requires accurate and precise control to balance the bottom hole pressure between the pore and fracture pressure of the reservoir. This paper presents three control schemes to stabilize the BHP prole, including proportional-integral(PI) control, PI with feed-forward control and adaptive PI with feed-forward control. The proposed schemes are carried out through simulations on a high-fidelity hydraulic drilling simulator for flow rate changes and BHP set-point changes. In fast set-point changes and flow r…

Fracture pressurePID controllerDrilling02 engineering and technology010502 geochemistry & geophysicsBottom hole pressure01 natural sciencesVolumetric flow ratelaw.inventionTracking error020401 chemical engineeringControl and Systems EngineeringControl theoryOil welllawOil well drilling0204 chemical engineeringGeology0105 earth and related environmental sciences
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Myocardial G Protein Receptor–Coupled Kinase Expression Correlates With Functional Parameters and Clinical Severity in Advanced Heart Failure

2010

In heart failure (HF), sympathetic hyperactivation induces deleterious effects in myocardial β-adrenergic signaling, with receptor down-regulation and desensitization mediated by G protein receptor-coupled kinases (GRKs). We hypothesised that changes in GRK isoforms may be associated with clinical status in advanced HF, using the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) scale.We included 31 patients with advanced HF undergoing transplantation. According to INTERMACS profiles, mRNA and protein levels of GRK isoforms in left ventricular (LV) myocardium were analyzed and compared with nonfailing LV samples.In failing LV myocardium, GRK2 and GRK5 (but not G…

G-Protein-Coupled Receptor Kinase 5Malemedicine.medical_specialtyG-Protein-Coupled Receptor Kinase 2Down-RegulationPolymerase Chain ReactionSeverity of Illness IndexGene Expression Regulation EnzymologicInternal medicinemedicineHumansRNA MessengerRegistriesReceptorG protein-coupled receptorHeart FailureG protein-coupled receptor kinasebiologybusiness.industryMyocardiumBeta adrenergic receptor kinaseStroke volumeMiddle AgedG-Protein-Coupled Receptor Kinasesmedicine.diseaseTransplantationEndocrinologySpainHeart failureCirculatory systembiology.proteinFemaleHeart-Assist DevicesCardiology and Cardiovascular MedicinebusinessJournal of Cardiac Failure
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Diffuse soil gas emissions of gaseous elemental mercury (GEM) from hydrothermal-volcanic systems: An innovative approach by using the static closed-c…

2016

This study was aimed to test a new methodological approach to carry out measurements of gaseous elemental mercury (GEM) diffusively emitted from soils in hydrothermal-volcanic environments. This method was based on the use of a static closed-chamber (SCC) in combination with a Lumex® RA-915M analyzer that provides GEM measurements in a wide range of concentrations (from 2 to 50,000 ng m-3). Gas samples were collected at fixed time intervals from the SCC positioned on the ground (time-series samples). The Lumex® inlet port was equipped with a three-way Teflon valve allowing the free entrance of air through a carbon trap, in order to: (i) prevent disturbance to the Lumex® operative flow rate …

GEM flux Diffuse soil degassing Air pollutant Hydrothermal gas010504 meteorology & atmospheric sciencesCalibration curveMineralogychemistry.chemical_elementGEM flux010502 geochemistry & geophysics01 natural sciencesImpact craterGeochemistry and PetrologyEnvironmental Chemistry0105 earth and related environmental sciencesgeographygeography.geographical_feature_categorySoil gasAir pollutantHydrothermal gasDiffuse soil degassingInletPollutionSettore GEO/08 - Geochimica E VulcanologiaVolumetric flow rateMercury (element)chemistryContour lineSoil waterFluid geochemistryApplied Geochemistry
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Positronium as a probe in natural polymers: decomposition in starch

2009

Ortho-positronium (o-Ps) is used as a probe in positron annihilation lifetime spectroscopy (PALS) experiments, to characterise the behaviour of free volumes in natural starch samples, as a function of temperature (T). Up to about 540 K, the o-Ps intensity, I(3), remains constant at 26.2% while its lifetime, tau(3), is found to increase linearly. Both parameters undergo a decrease above this T, due to the onset of decomposition, which results in a shrinking of the sample pellets. The results indicate that the glass transition temperature should be above 501 K. Data from thermal gravimetry analysis (TGA) measurements are well described by supposing a first order process for the survival proba…

GLASS-TRANSITIONAnalytical chemistryGeneral Physics and AstronomyElectrons02 engineering and technologyActivation energy01 natural sciencesPositroniumNuclear magnetic resonance0103 physical sciencesPhysical and Theoretical ChemistrySpectroscopyThermal analysisBiological Products010304 chemical physicsChemistrySpectrum AnalysisTransition temperatureTemperatureStarchFREE-VOLUME021001 nanoscience & nanotechnology[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry[ CHIM.POLY ] Chemical Sciences/PolymersThermogravimetry[CHIM.POLY]Chemical Sciences/PolymersThermogravimetry[ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistryVolume fraction0210 nano-technologyGlass transitionANNIHILATION LIFETIMEPhysical Chemistry Chemical Physics
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Scale-up and viscosity effects on gas–liquid mass transfer rates in unbaffled stirred tanks

2018

Abstract The interest in the process industry on unbaffled stirred tanks has greatly expanded in the last years because they may bring about significant advantages in a number of applications, including biochemical, food and pharmaceutical processes where the presence of baffles is undesirable for several reasons. Despite their application potential, unbaffled vessels still lack fundamental information, due to the fact that only recently their capabilities have started being dug out. The lack of information on scale up effects is possibly the main reason hindering practical applications. In this work the influence of vessel size and liquid viscosity on the mass transfer performance in unbaf…

Gas-“liquid mass transferWork (thermodynamics)Scale-upSettore ING-IND/25 - Impianti ChimiciGeneral Chemical EngineeringBioreactorUnbaffledBaffle02 engineering and technologyViscosityStirred tank020401 chemical engineeringMass transferChemical Engineering (all)0204 chemical engineeringScale (chemistry)Chemistry (all)General ChemistryMechanics021001 nanoscience & nanotechnologyViscosity effectVessel diameterVolume (thermodynamics)SCALE-UPEnvironmental science0210 nano-technologyChemical Engineering Research and Design
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In vivo measurement of gastric fluid volume in anesthetized dogs

2020

Abstract The drug solubility is critical for the Biopharmaceutics Classification System (BCS), yet the criteria for solubility have not been precisely defined for dogs. In particular, the gastric fluid volume (GFV) of dogs which is used to measure the solubility has not been quantified in vivo. The aim of the work is to measure the GFV using magnetic resonance imaging (MRI) from 12 Beagle dogs weighing 9–12 kg (6 male and 6 female). We found that the average GFV within this weight range was 24.0 ± 4.2 mL. The result can be used for the BCS studies of canine drugs and also serves as a reference for other species.

Gastric fluidmedicine.diagnostic_testbusiness.industryPharmaceutical ScienceMagnetic resonance imaging02 engineering and technology021001 nanoscience & nanotechnologyWeight rangeBiopharmaceutics Classification System030226 pharmacology & pharmacyBeagle03 medical and health sciences0302 clinical medicineVolume (thermodynamics)In vivoMedicineSolubility0210 nano-technologybusinessBiomedical engineeringJournal of Drug Delivery Science and Technology
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Oxidation of organics in water in microfluidic electrochemical reactors: Theoretical model and experiments

2011

The electrochemical oxidation of organics in water performed in micro reactors on boron doped diamond (BDD) anode was investigated both theoretically and experimentally in order to find the influence of various operative parameters on the conversion and the current efficiency CE of the process. The electrochemical oxidation of formic acid (FA) was selected as a model case. High conversions for a single passage of the electrolytic solution inside the cell were obtained by operating with proper residence times and low distances between cathode and anode. The effect of initial concentration, flow rate and current density was investigated in detail. Theoretical predictions were in very good agr…

General Chemical EngineeringAnalytical chemistryFormic acidWastewaterElectrochemistrylaw.inventionElectric reactorCurrent densitylawMass transferSh numberElectrochemistryMicro deviceMass transferBubble formationMicro reactorMass transfer coefficientChemistryWastewater treatment Electrochemical oxidationLimiting currentSettore ING-IND/27 - Chimica Industriale E TecnologicaCathodeAnodeVolumetric flow rateTheoretical models BoronBDDCurrent densityForecastingElectrochimica Acta
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Ultrasonic and Volumetric Properties of 1-Ethyl-3-methylimidazolium Trifluoromethanesulfonate Ionic Liquid with 2-Propanol or Tetrahydrofuran at Seve…

2011

Densities and speeds of sound of 1-ethyl-3-methylimidazolium trifluoromethanesulfonate mixtures with 2-propanol and tetrahydrofuran (THF), as well as of the pure components, have been measured over the whole range of compositions at T = (278.15 to 328.15) K and P = (101 ± 2) kPa. From these experimental data, the excess molar volume, excess speed of sound, and excess isentropic compressibility have been calculated and fitted to an extended version of the Redlich–Kister equation, which takes into account the dependence on composition and temperature simultaneously. The Prigogine–Flory–Patterson theory has also been used to explain the behavior of these systems.

General Chemical EngineeringAnalytical chemistryGeneral ChemistryPropanolchemistry.chemical_compound1-ethyl-3-methylimidazoliumMolar volumechemistrySpeed of soundIonic liquidOrganic chemistryUltrasonic sensorTrifluoromethanesulfonateTetrahydrofuranJournal of Chemical & Engineering Data
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Heat pipe controlled syntheses of ionic liquids in microstructured reactors

2009

Abstract The combination of a heat pipe and a microstructured reactor allows to perform highly exothermal reactions under safe conditions. First experiments for the synthesis of 1,3-dimethylimidazolium-triflate from 1-methylimidazol and methyl triflate showed that at high flow rates of more than 5 ml/min through a single 300 μm × 500 μm wide and 400 mm long channel quantitative conversion could be achieved. This chemical reaction, known for extreme heat release, can be retained under thermal control even at much higher flow rates.

General Chemical EngineeringGeneral ChemistryChemical reactionThermal controlIndustrial and Manufacturing EngineeringVolumetric flow rateExtreme heatchemistry.chemical_compoundHeat pipeChemical engineeringchemistryIonic liquidEnvironmental ChemistryOrganic chemistryMicroreactorHigh flowChemical Engineering Journal
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