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Relative and specific

In these equations f/,p is defined as the specific viscosity, is the relative viscosity, is the reduced viscosity and [> ] is the intrinsic viscosity. The relative and specific viscosities are dimensionless and the intrinsic viscosity is either expressed in decilitres per gram or millilitres per gram, i.e. the inverse of concentration. [Pg.59]

In molecules that contain only sp atoms, free rotation occurs as described in Section 8.1. However, once atoms are attached in a specific manner to an sp atom, as in 1, the only way to change the relative and specific positions of groups A-D is to make or break bonds. In that sense, once attached, the absolute positions of the groups are fixed. If the A-D groups attached to the sp center are different from each other, a new type of stereoisomer is possible. [Pg.355]

Intrinsic viscosity (rj) is the viscosity of an infinitely diluted polymer solution. It is a measure of the hydrodynamic volume occupied by a macromolecule, which is closely related to the size and conformation of the chain, but is independent of concentration of macromolecule. In dilute solutions, by definition, the polymer chains are separated and there is negligible interaction between them. Therefore, the (rj) of polymer in solution depends only on the dimension and the molecular weight of polymer chain. Experimentally determined values of the relative and specific polymer viscosities were used to calculate it, according to Huggins [53] and Kraemer [64] equations given by... [Pg.149]

The two /3-turn structures, pc and Pe are the most stable among those considered. This is in accord with the unconstrained nanosecond simulations of linear DPDPE, which converged to these conformers [14]. Because the cyclic form is relatively rigid, it is assumed that the conformation it adopts in solution is the biologically active one, responsible for its high affinity and specificity towards the 5 opioid receptor. The relatively low population of the cyclic-like structure for the linear peptide thus agrees qualitatively with the... [Pg.170]

Most chemical iavestigations with plutonium to date have been performed with Pu, but the isotopes Pu and Pu (produced by iatensive neutron irradiation of plutonium) are more suitable for such work because of their longer half-Hves and consequendy lower specific activities. Much work on the chemical properties of americium has been carried out with Am, which is also difficult to handle because of its relatively high specific alpha radioactivity, about 7 x 10 alpha particles/(mg-min). The isotope Am has a specific alpha activity about twenty times less than Am and is thus a more attractive isotope for chemical iavestigations. Much of the earher work with curium used the isotopes and Cm, but the heavier isotopes... [Pg.216]

From the definition of specific speed (eqs. 9 and 10), it follows that reciprocating pumps operate at high pressures and low flow rates. Conversely, centrifugal pumps are appHed at lower pressures and higher flow rates. Many rotary pumps are selected for viscous Hquids having pressures equal to or less than, and capacities lower than, centrifugal pumps. However, these limits are relative and a gray area exists as some pump types cross boundaries into the domain of other types. [Pg.297]

Eor products having relatively low specific activity, such as some compounds labeled with and which are synthesized on the scale of several millimoles, classical organic chemical separation methods may be utilized, including extraction, precipitation, and crystallization. Eor separation of complex mixtures and for products having high specific activity, such as those labeled with tritium, etc, chromatographic methods utilizing paper, thin... [Pg.438]

A study was conducted to measure the concentration of D-fenfluramine HCl (desired product) and L-fenfluramine HCl (enantiomeric impurity) in the final pharmaceutical product, in the possible presence of its isomeric variants (57). Sensitivity, stabiUty, and specificity were enhanced by derivatizing the analyte with 3,5-dinitrophenylisocyanate using a Pirkle chiral recognition approach. Analysis of the caUbration curve data and quaUty assurance samples showed an overall assay precision of 1.78 and 2.52%, for D-fenfluramine HCl and L-fenfluramine, with an overall intra-assay precision of 4.75 and 3.67%, respectively. The minimum quantitation limit was 50 ng/mL, having a minimum signal-to-noise ratio of 10, with relative standard deviations of 2.39 and 3.62% for D-fenfluramine and L-fenfluramine. [Pg.245]

Example 8 Determination of Air Properties For a barometric pressure of 25.92 inHg (Ap = —4), a dry-bulb temperature of 90 F, and a wet-bulb temperature of 70 F determine the following absolute humidity, enthalpy, dew point, relative humidity, and specific volume. [Pg.1161]

In a series of reviews [244-246] the models proposed for the assessment of the effect of fillers on the complex of PCM properties are discussed. Analysis of the models shows that, for a fixed filler content, the strength must be higher in compositions with fillers featuring the absolute adhesion to the matrix than in systems with little or no adhesion. The relative elongation and specific impact strength must, on the contrary, go up with the increasing adhesion. [Pg.35]

Five-membered heteroaromatic ring compounds have been extensively studied in terms of their relative reactivity and specific physicochemical properties. In particular, it is generally accepted that the degree of aromaticity follows the order... [Pg.49]

When a polymer is prepared by radical polymerization, the initiator derived chain-end functionality will depend on the relative significance and specificity of the various chain end forming reactions. Tlius, for the formation of telechelic polymers ... [Pg.375]

A relatively new class of fluorocarbon composite nronlrits with relatively high specific impulse and a high density impulse have been tested as booster rockets for 5-inch projectiles. [Pg.890]

Study on mechanisms of ordered molecular films as a model lubricant is of particular importance in the field of micro and nano-tribology, for it would help to understand how molecules contribute to the creation of friction and wear. The understanding has been much improved in recent years through MD simulations, performed by investigators around the world, to detect interactions between the molecular films in relative motion, and to reveal the process and specific mode of energy dissipation. [Pg.90]


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Relative specificity

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