Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Industrial and engineering chemistry 25 (1986), S. 277-282 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Colloid & polymer science 261 (1983), S. 846-854 
    ISSN: 1435-1536
    Keywords: Melt flow index ; multicomponent polymeric systems ; altered free volume ; state concept
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A model based on the altered free volume state concept has been proposed here to predict the melt flow index values of multicomponent systems as a function of the amount of the dispersed phase. The predictions of the model have been compared with experimental results reported in the literature on a diverse range of multicomponent polymeric systems. The agreement between the model predictions and the experimentally determined values is good.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Colloid & polymer science 262 (1984), S. 319-337 
    ISSN: 1435-1536
    Keywords: Drag reduction review ; micellar system ; polymer additive ; biological additive ; suspension ; theory of drag reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A state-of-the-art review on drag reduction has been presented in order to bring out some important aspects of the drag reduction phenomenon and its potential for practical use. The review is biased towards micellar systems and discusses in detail the morphological differences between drag reducing polymeric and micellar systems. Work relating to polymeric systems has not been dealt in detail as it has been the subject of earlier reviews. Studies relating to biological additives as well as suspensions have been briefly mentioned without detailed discussion as their potential for practical use presently appears] to be limited.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Rheologica acta 15 (1976), S. 658-664 
    ISSN: 1435-1528
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Zusammenfassung Ein ungewöhnliches Widerstandsverminderungs-Verhalten wird bei dem nicht-ionischen oberflächenaktiven Stoff Lubrol 17A10 in Anwesenheit des Elektrolyten K2SO4 beobachtet. Das System zeigt bei Zimmertemperatur ein normales Turbulenz-Verhalten, erlangt dagegen bei einer Temperatur in der Nähe des Trübungspunktes die Fähigkeit, die Reibung herabzusetzen. Die Konsequenzen eines derartigen Widerstandsverminderungs-Effekts bei erhöhter Temperatur werden unter dem Gesichtspunkt der Verwendbarkeit solcher Additive in Zentralheizungs-Systemen diskutiert.
    Notes: Summary An unusual drag reducing behaviour of the nonionic surfactant Lubrol 17 A 10 in the presence of the electrolyte K2SO4 has been observed. The system shows normal turbulent flow behaviour at room temperature, but depicts an ability to reduce friction when flowing at a temperature at and around its cloud point. The consequences of this elevated temperature drag reduction have been discussed from the viewpoint of using drag reducers in central heating systems.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Rheologica acta 22 (1983), S. 209-222 
    ISSN: 1435-1528
    Keywords: Rheogram ; engineering thermoplastics ; melt flow index
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Abstract A method proposed earlier has been extended to estimate complete flow curves or rheograms of engineering plastics. Master curves that are independent of the grade and temperature have been generated and presented for acrylics, polyacetal, nylons, polyethylene terephthalate, polycarbonate and polysulfone. The influence of the various molecular parameters on the viscosity behaviour of polymer melts have been explained rationally. More specifically, the effects of chain branching and of chain rigidity on the master curve of a resin type have been elucidated with reference to polyacetal and polysulfone, respectively. The method presented here can be used effectively by processors of engineering plastics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Rheologica acta 22 (1983), S. 90-101 
    ISSN: 1435-1528
    Keywords: Melt flow index ; rheogram ; master curve ; polymeric melt
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Abstract A knowledge of the complete flow curve or rheogram of a polymeric melt depicting the variation of the melt viscosity over industrially relevant range of shear rate and temperature is essential in the design of polymer processing equipment, process optimization and trouble-shooting. These data are generated on sophisticated rheometers that are beyond the financial and technical means of most plastics processors. The only flow parameter available to the processor is the melt flow index of the material. In the present work, a method has been proposed to estimate the rheograms of a melt at temperatures relevant to its processing conditions with the use of a master curve, knowing the melt flow index and glass transition temperature of the material. Master curves that coalesce rheograms of different grades at various temperatures have been generated and presented for low density polyethylene, high density polyethylene, polypropylene, polystyrene and styrene-acrylonitrile copolymer.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Die Untersuchung bezieht sich auf die voll ausgebildete Strömung und den Wärmeübergang in einem von zwei parallelen Wänden begrenzten Kanal bei konstantem Wärmefluß am Rande. Der Kanalraum wird von einem hochporösem Medium ausgefüllt, das mit einem elastischen Fluid konstanter Zähigkeit getränkt ist. Der Einfluß des Reibungswiderstandes an den Kanalgrenzen auf das Wärmeübertragungsverhalten wird mit Hilfe des von Brinkman erweiterten Darcy-Transportgesetzes ermittelt. Die Lösung erfolgte unter Anwendung eines näherungsweisen gültigen Integralverfahrens.
    Notes: Abstract An analysis is presented of fully developed flow and heat transfer in a channel confined by two parallel walls subjected to uniform heat flux in a highly porous medium saturated with an elastic fluid of constant viscosity. The Brinkman-extended Darcy model is used for studying the effect of the boundary viscous frictional drag on the heat transfer characteristics. The approximate integral method is employed to obtain a solution.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Heat and mass transfer 20 (1986), S. 219-227 
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Es wird eine theoretische Analyse für den Wärmeübergang bei Zwangskorivektion von äußeren in nicht-Newtonsche Fluide eintauchende Oberfläche unter Benutzung des Exponentialansatzes vorgeschlagen. Dabei wurde die früher für Newtonsche Fluide eingeführte Integralbehandlung erfolgreich auf nicht-Newtonsche Fluide erweitert, die über eine ebene Platte und einen Keil beliebigen Winkels strömen. Die integralen Impuls- und Energiegleichungen werden in ein Paar charakteristischer Gleichungen transformiert, die für den Geschwindigkeits-Formfaktor und für das Grenzschicht-Dickenverhältnis leicht gelöst werden können, wenn die Exponenten in den Ausdrücken für den Potenzansatz die Anströmgeschwindigkeit und die Änderung der Wandtemperatur spezifiziert sind. Es stellte sich heraus, daß eine asymptotische Näherung, die unter der Annahme großer Prandtl-Zahl abgeleitet wurde, für Fluide beliebigen Potenzansatzes praktisch gültig ist und dadurch für eine rasche und trotzdem genaue Abschätzung des örtlichen Wärmeübergangs an nicht-Newtonsche Fluide benützt werden kann.
    Notes: Abstract A theoretical analysis has been proposed for the forced convection heat transfer from external surfaces immersed in non-Newtonian fluids of the power-law model. The integral treatment previously introduced for Newtonian fluids has been successfully extended to the non-Newtonian fluids over a flat plate and a wedge of an arbitrary included angle. The integral momentum and energy equations are transformed into a pair of characteristic equations, which can readily be solved for the velocity shape factor and the boundary layer thickness ratio, once the exponents in the expressions for the power-law model, free stream velocity and wall temperature variation are specified. It has been also found that an asymptotic expression derived under the assumption of large Prandtl number, is valid practically for all power-law fluids, and hence, can be used for a speedy, and yet accurate estimation of the local heat transfer to non-Newtonian fluids.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Heat and mass transfer 21 (1987), S. 15-18 
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Es wird der Einfluß des Auftriebes auf den Wärmeübergang bei turbulenter Aufwärtsströmung von widerstandsreduzierenden Fluiden in vertikalen Rohren theoretisch analysiert. Dabei wird ein Kriterium für die Begrenzung der Abnahme des Wärmeübergangs auf weniger als 5% für Fluide unterschiedlicher Widerstandsverringerung aufgestellt. Die endgültige mathematische Formulierung für die quantitative Beschreibung des Einflusses der natürlichen Konvektion auf die erzwungene Konvektion konnte sowohl auf Aufwärts-als auch auf Abwärtsströmung eines Fluids mit vermindertem Strömungswiderstand einfach dadurch angewandt werden, daß man ein Vorzeichen in dem die Strömung bestimmenden Term ändert.
    Notes: Abstract The effect of buoyancy on the heat transfer during upward turbulent flow of drag reducing fluids in vertical tubes has been theoretically analyzed. A criteria has been established for limiting the decrease in heat transfer to less than 5% for fluids of varying drag reducing ability. The final expression for quantitative evaluation of natural convection effect on forced convection could be applied to upward as well as downward turbulent flow of drag-reducing fluids merely by a change in sign of the controlling term.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 18 (1983), S. 2149-2155 
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Addition of metal halides to nylons has been shown to be advantageous in a number of ways. The decrease in melting temperature, increase in glass transition temperature and melt viscosity by such additions have allowed more convenient processing of low molecular weight polymers and thermally unstable polymers. Rheological data depicting the variation of melt viscosity with shear rate at temperatures relevant to processing are necessary in optimizing and trouble-shooting plastics processing operations. In the present paper, a method has been proposed to estimate, complete flow curves or rheograms of nylon—metal halide systems with the use of a master curve knowing the melt flow index and glass transition temperature of the system. The validity of the approach has been verified for the nylon 6—lithium chloride system and shown to hold good for any nylon—metal halide combination.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...