Physical property determination

Because of the recent claims of room-temperature superconductivity in materials by several research groups, two additional criteria are further required to certify that a material is superconducting. These are long-term stability, and reproducibility in the preparation and physical property determination,... 

PHYSICAL PROPERTY DETERMINATION ON TERNARY COPPER OXIDES- STUDIES ON COPPER OXIDE SYSTEMS PRIOR TO 1985... 

It must be emphasized that to proceed from the raw evaluation data to full-scale production is not the preferred step. Further evaluation of the processability of the feedstock is usually necessary through the use of a pilot-scale operation. To take the evaluation of a feedstock one step further, it may then be possible to correlate the data obtained from the actual plant operations (as well as the pilot plant data) with one or more of the physical properties determined as part of the initial feedstock evaluation. 

In measurements of physical properties of epoxy resins - and the epoxy-polyim-ide system will be included in this general categorization - the method of failure is of considerable interest. Gross flaws in the epoxy structure act as initiation points for cracks which typically propagate by the breaking crosslinks. Therefore the level of crosslinking and cure will have a significant influence on the physical properties determined. The incorporation of additives that typically... 

Physical Properties Determining Chargeability of Pesticide Sprays... 

Because of the great depth of the ocean, the most important physical property determining the solubility of carbonate minerals in the sea is pressure. The pressure dependence of the equilibrium constants is related to the difference in volume, AV, occupied by the ions of Ca and in... 

Blurock, E.S. (1998). Use of Atomic and Bond Parameters in a Spectral Representation of a Molecule for Physical Property Determination. J.Chem.Inf.Comput.Sci.,38,1111-1118. 

What physical property determines the height at which hydrocarbons condense in a fractionation tower (22.5)... 

Ten selected blends were prepared and critical physical properties determined. Statistical techniques were used to develop empirical equations relating the resultant properties to blend composition. Scheffd canonical polynominal models and response surfaces provided a thorough understanding of the mixture system. These models were used to determine the amount of coal-tar pitch that could be incorporated into ABS compounds that would still meet ASTM requirements for various pipe-material designations. 

Har-el Y, van Zanten JH, Hanes J. Effect of formulation parameters on PEI/VEGF DNA polyplex physical properties determined using time-resolved multiangle laser light scattering, in preparation. 

The physical properties determined using the ECD are important to different areas of chemistry. Analytical chemistry deals with how much and what are involved in a chemical reaction. Expressed differently, it establishes what we refer to as the QQQ quantitation, qualitative identification, and the quality of the results. The determination of the electron affinities of the chlorinated biphenyls, dioxins, and phenols and the prediction of the response of the ECD and NIMS are important to qualitative and quantitative analyses of environmental pollutants [21]. Polarographic reduction in solutions likewise gives accurate and precise qualitative and quantitative results. The quality of the analyses is expressed by the random and systematic uncertainties in the reported values. These are obtained from the same principle of weighted least squares used to obtain information from ECD data. Wentworth has described the application of the general least-squares procedure to chemical problems [22, 23]. 

Physical properties determined on a few well-spaced and easily isolated dimethyldecalins are listed in Table XXVI. These results, along with similar data on the monomethyldecalins from Table XVII and available data on cis- and retention time. The correlations are good but are probably more valuable for estimating properties than for predicting structures. 

The formation of an amide bond by organic chemical methods Is usually accomplished by reacting the acid halogenlde and the amino acid unless the acid substrate contains other reactive groups. The acid chloride Is prepared directly with thlonyl chloride (244) or Indirectly via the formation of a mixed anhydride by use of another acid halogenlde (245,246). Isotoplcally labeled [(2,4-Dlchlorophenoxy)acetyl]valine was synthesized by a DCC catalyzed reaction between the acid and valine (247). A few examples of synthetic amino acid conjugates of xenobiotics are shown In Table X. Several taurine conjugates of both alkanolc and benzylic acids have been synthesized and their physical properties determined by Idle et al. (2 ). 

The pKa value is numerically equal to the pH value at which a molecule is half dissociated and the calculation or determination of the pK value(s) of a potential candidate drug should be one of the flrst physical properties determined. The approximate pK of the molecule of interest can be estimated by referring to literature values for substituents and similar molecules.A range of experimental techniques such as potentiometry, solubility determinations or ultraviolet-visible spectroscopy may be used for determination of the true pK value(s). 

Surrey, T, Nedelec, R, Leibler, S. et al. (2001). Physical properties determining self-organization of motors and microtubules. Science, 292, 1167-71. 

Application of an electric field to a substance causes a partial alignment of polar molecules thus molecular dipole moments contribute to the dielectric constant of a liquid or solid, one of the most important physical properties determining the behavior of a solvent (see Topic E1Y In nonpolar substances the dielectric constant arises from the molecular polarizability, and is generally much smaller than with polar molecules. 

Many physical properties determine the performance of the plasma source as well as how well the plasmas are able to activate the polymer surface. The physical properties of different types of atmospheric pressure plasmas are shown in Table 8.2. In a torch, plasma densities can be extremely high, from 10 to 10 cm, with average electron temperatures of 1-2 eV (1.0 eV = 11,605 K) whereby the density of neutral species is lO cm Because of the heat-sensitive... 

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