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Bagley method

The calculations performed must be seen as no more than approximations, since they are based on the assumption of Newtonian behaviour, something from which polymer dispersions are far away. For this reason the instrument offers two correction methods the Bagley method for determining the true shear stress t and the Rabinowitsch method for correcting the shear rate. [Pg.532]

Piston rates were selected in order to cover a shear rate range of 10-5200 sec l with the three dies used. The corrections for entrance pressure loss were determined according to the Bagley method (23), in order to calculate the corrected shear stress. Results, as given in Table VII in terms of apparent viscosity and (instantaneous) extrudate swell, are essentially similar to the ones published by Goettler, Richwine and Wille (32). [Pg.200]

Further improvements to this method have been reported by Bagley. The requirement of harsh thermal conditions to facilitate the cyclodehydration can be minimized by simply adding acetic acid or Amberlyst 15. Alternatively, one could use Lewis acids such as ZnBr2 or Yb(OTf>3 in catalytic amounts. [Pg.310]

The Bohlmann-Rahtz synthesis of trisubstituted pyridines from /3-aminocrotonates and an ethynyl ketone has found application in the preparation of a variety of heterocycles based on the substituted pyridine motif. Bagley and coworkers have developed a microwave-assisted modification of this one-pot heteroannulation method that is best conducted in dimethyl sulfoxide at 170 °C for 20 min, providing the desired pyridines in 24—94% yield (Scheme 6.227) [406, 407]. Typically, 2 equivalents of the /3-aminocrotonates were employed. [Pg.250]

Bagley, D.M., Dong, B.M. and De Salva, S.J. (1989). Assessing the eye irritation potential of surfactant-based materials using the chorioallantoic membrane vascular assay (CAMVA). In Alternative Methods in Toxicology, Vol. 7 (Goldberg, A.M., ed.) Mary Arm Liebert, New York, pp. 265-272. [Pg.677]

S. Reinhart, "Application of the Engrave-ment Method to the Study of Particle Velocity Distribution in Explosively Loaded Cylinders , JApplPhys 26, 1431-35(1955) NOTS 1385, NavQrd 5040, (2 Mar 1956) 9) C.H. Bagley... [Pg.209]

Fig 24 compares experimental entrance pressure losses of LLDPE obtained using Bagley correction and numerical results obtained with the three models, but using diSerent methods. [Pg.319]

Of course, polymier melts are non-Newtonian due to their shear-thinning behavior. The value calculated from Eq. (6.1) must be corrected for the shear rate at the wall, which is higher for a polymier melt than that calculated by Eq. (6.1). This method is known as the Rabinowitsch correction and is based on determination of viscosity at a location inside the flow channel as opposed to the wall. At a representative location, Newtonian and non-Newtonian shear rates coincide. This location is at r = nR/4, where the pressure transducer should be located to measure the pressure drop. Another correction has to be made for other pressure losses it is called the Bagley correction. PI... [Pg.197]

Kleinheinz G.T. and Bagley S.T. (1997) A filter paper method for the recovery and cultivation of microorganisms utilizing volatile organic compounds. J. Microbiol. Methods, 29, 139-144. [Pg.271]

The difference between single and twin-bore capillary rheometers (Fig. 9) cannot be dealt with in this contribution. Basically this is a matter of being able to make the so-called Bagley correction with less effort and fewer errors. Likewise, no reference can be made here as to how dilatant respectively structural viscose behaviour (Rabinowitsch correction) and the strain properties of ceramic bodies or wall slipping effects (according to the Mooney method) can be determined with the capillary rheometer. [Pg.393]

Other methods used to obtain amorphous alloys are electro-deposition (Bagley and Turnbull, 1968 Boucher et al. 1976) and electrodeless precipitation (Brenner and Riddell, 1947 Dixmier and Doi, 1963), ion implantation (Andrews et al., 1976 Grant, 1978) and solid state reaction (Schwarz and Johnson, 1983). Since these methods are less widely used than vapour quenching and liquid quenching, they will not be discussed in this section. [Pg.271]

Bagley, R.D. (1974) Extmsion method for forming thin-waUed honeycomb stmctures. US Patent 3,790,654. [Pg.198]

The excess pressure drop associated with the entrance and exit is shear-rate dependent for polymer melts. If the excess pressure drop can be measured, then it can be subtracted from the total pressure drop to provide the value for fully developed flow, and the latter can be used to compute the shear stress at a given shear rate. The method commonly used is known as a Bagley plot. Here, the pressure drop as a function of shear rate is measured in capillaries of varying length-to-diameter L/D) ratios. The data are then plotted as pressure drop versus L/D at fixed shear... [Pg.149]

PJ Bagley, J Selhub. Analysis of folates using combined affinity and ion-pair chromatography. Methods Enzymol 281 16—25, 1997. [Pg.331]

The use of fractional derivatives for the constitutive equation allows us to define a more general, rheological element (Bagley 1989). A high bandwidth fit is possible using fewer variables than Prony s method. The relation of stress T and strain S for the fractional element is defined as... [Pg.734]

The most accurate method for determining pe is to make a Bagley plot with at least two short dies of the same diameter. Another approach is to measure p directly with an orifice die and use it to correct data from one long die. This method usually requires using two different transducers because of the great difference in pressure. [Pg.250]

Weaver, M.O., Bagley, E.B., Fanta, G.F. and Doane, W.M., 1976, Method of Reducing Water Content of Emulsions, Suspensions, and Dispersions with Highly Absorbent Starch-Containing Polymeric Compositions. U.S. Pat. 3935099. [Pg.204]


See other pages where Bagley method is mentioned: [Pg.191]    [Pg.229]    [Pg.108]    [Pg.191]    [Pg.229]    [Pg.108]    [Pg.74]    [Pg.228]    [Pg.665]    [Pg.77]    [Pg.287]    [Pg.295]    [Pg.175]    [Pg.314]    [Pg.314]    [Pg.165]    [Pg.360]    [Pg.148]    [Pg.314]    [Pg.192]    [Pg.167]    [Pg.630]    [Pg.520]    [Pg.427]    [Pg.479]    [Pg.292]    [Pg.246]    [Pg.846]    [Pg.62]    [Pg.64]    [Pg.506]    [Pg.102]    [Pg.250]    [Pg.334]    [Pg.102]   
See also in sourсe #XX -- [ Pg.108 ]




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