Quantitative interpretation

One more significant aspect of modem microscopy is the quantitative interpretation of the images in terms of the microstmcture of the object. Although most microscopes include or can be combined with powerful image processing systems, the interpretation of the contrast is still the main problem. On the other hand, reliable micromorpbological information could be easily obtained from a set of thin flat cross sections which reveal only density information, from which case accurate two- and three-dimensional numerical parameters of the internal microstmcture could be calculated. 

In order to develop a quantitative interpretation of the effects contributing to heats of atomization, we will introduce other schemes that have been advocated for estimating heats of formation and heats of atomization. We will discuss two schemes and illustrate them with the example of alkanes. Laidler [11] modified a bond additivity scheme by using different bond contributions for C-H bonds, depending on whether hydrogen is bonded to a primary (F(C-H)p), secondary ( (C-H)g), or tertiary ( (C-H)t) carbon atom. Thus, in effect, Laidler also used four different kinds of structure elements to estimate heats of formation of alkanes, in agreement with the four different groups used by Benson. 

Which of the two models for the mode of ATP interaction with myosin do these data support Explain your answer by quantitative interpretation of the light-scattering data. 

R. H. Richardson and co-workers, "Ha2ards Analysis Through Quantitative Interpretation of Sensitivity Testing," in Proceedings of the International... 

Because iCg values for competitive antagonists represent tme dissociation constants, these make possible quantitative interpretations of SARs. Significant use also has been made of iCg values in the quantitative comparison of receptors to determine whether receptors that respond to the same agonists are identical or whether responses produced by different agonists are initiated at the same receptors (44,46). Thus, beta-adrenoceptors in human and guinea pig preparations can be direcdy compared and selective and antagonists quantitated (Table 3). 

Electric field measurement at the boundary of a metal container filled with charged material. Examples include pipelines and storage vessels. The electric field can be used to calculate charge density (3-5.1). Eield meters can also be lowered into containers such as silos to determine the local fields and polarities. Quantitative interpretation of the reading requires correction for field intensification and is sometimes accomplished using computer simulations. 

It is worthwhile to present this episode in eonsiderable detail, beeause it eneapsulates very elearly what was new in physieal metallurgy in the middle of the eentury. The elements are an aecurate theory of the effects in question, preferably without disposable parameters and, to check the theory, the use of a technique of measurement (the Snoek pendulum) which is simple in the extreme in construction and use but subtle in its quantitative interpretation, so that theory ineluctably comes into the measurement itself. It is impossible that any handwaver could ever have conceived the use of a pendulum to measure dissolved carbon concentrations ... 

The biological determinant is an indicator of exposure to the chemical, but the quantitative interpretation of the measurement is ambiguous. These determinants should be used as a screening test if a quantitative test is not practical or as a confirmatory test if the quantitative test is not specific and the origin of the determinant is in question. 

The reactivity modification or the reaction rate control of functional groups covalently bound to a polyelectrolyte is critically dependent on the strength of the electrostatic potential at the boundary between the polymer skeleton and the water phase ( molecular surface ). This dependence is due to the covalent bonding of the functional groups which fixes the reaction sites to the molecular surface of the polyelectrolyte. Thus, the surface potential of the polyion plays a decisive role in the quantitative interpretation of the reactivity modification on the molecular surface. 

In semi-cristalline polymers, rate-enhancement under stress has been frequently observed, e.g. in UV-photooxidation of Kapron, natural silk [80], polycaprolactam and polyethylene terephthalate [81]. Quantitative interpretation is, however, difficult in these systems although the overall rate is determined by the level of applied stress, other stress-dependent factors like the rate of oxygen diffusion or change in polymer morphology could occur concurrently and supersede the elementary molecular steps [82, 83], Similar experiments in the fluid state showed unequivocally that flow-induced stresses can accelerate several types of reactions, the best studied being the hydrolysis of DNA [84] and of polyacrylamide [85]. In these examples, hydrolysis involves breaking of the ester O —PO and the amide N —CO bonds. The tensile stress stretches the chain, and therefore, facilitates the... 

However, some quantitative interpretation of the rates of outer-sphere reactions may be made. It is possible to determine the rate constant, kn for the reaction of two complex ions and [M Lg] (Eq. 9.26). 

Cf The biological determinant is an indicator of exposure to the chemical but the quantitative interpretation of the measurement is ambiguous. 

Overbeek, JTG, Quantitative Interpretation of the Electrophoretic Velocity of Colloids. In Advances in Colloid Science Mark, H Verwey, EJW, eds. Interscience New York, 1950 Vol. 3, p 97. 

A quantitative interpretation of aldonolactone inhibition in terms of an adaptation of the active site to a transition state approaching a planar, glycosyl oxocarbonium ion is made difficult for several reasons. Due to the interconversion between the 1,4- and 1,5-lactones, and their hydrolysis to the aldonic acids, their use is limited to kinetic studies with incubation times of 10 min or less. This was not realized by most investigators prior to 1970. In many cases, only the 1,4-lactone can be isolated its (partial) conversion into... 

A related experiment TOCSY (Total Correlation Spectroscopy) gives similar information and is relatively more sensitive than the REIAY. On the other hand, intensity of cross peak in a NOESY spectrum with a short mixing time is a measure of internuclear distance (less than 4A). It depends on the correlation time and varies as . It is positive for small molecules with short correlation time (o r <<1) and is negative for macromolecules with long correlation time (wr >>l) and goes through zero for molecules with 1 Relaxation effects should be taken into consideration for quantitative interpretation of NOE intensities, however. 

The advantages of SIMS are its high sensitivity (detection limit of ppms for certain elements), its ability to detect hydrogen and the emission of molecular fragments that often bear tractable relationships with the parent structure on the surface. Disadvantages are that secondary ion formation is a poorly understood phenomenon and that quantification is often difficult. A major drawback is the matrix effect secondary ion yields of one element can vary tremendously with chemical environment. This matrix effect and the elemental sensitivity variation of five orders of magmtude across the periodic table make quantitative interpretation of SIMS spectra oftechmcal catalysts extremely difficult. 

Replacement of gas by the nonpolar (e.g., hydrocarbon) phase (oil phase) has been sometimes used to modify the interactions among molecules in a spread film of long-chain substances. The nonpolar solvent/water interface possesses an advantage over that between gas and water in that cohesion (i.e., interactions between adsorbed molecules) due to dipole and van der Waals s forces is negligible. Thus, at the oil/water interfaces, the behavior of adsorbates is much more ideal, but quantitative interpretation may be uncertain, in particular for the higher chains, which are predominantly dissolved in the oil phase to an unknown extent. The oil phase is poured on the surface of an aqueous solution. Thus, the hydrocarbon, such as heptane or decane, forms a membrane a few millimeters thick. It is thicker than the adsorbed monolayer. Owing to the small difference in dielectric constant between the air and a hydrocarbon oil, the... 

However, going from the former qualitative analysis to a more quantitative one is much more troublesome, as the correct and quantitative interpretation of the results should carefully take into account all the steps into which the process of image formation in the electron microscope is divided. 

Ellis, A.J. (1970) Quantitative interpretation of chemical characteristics of hydrothermal systems. Proc. United Nations Symp. Development and Utilization of Geothermal Resources, Risa, 1970, vol. 2, Part 1. Geothermics, Special Issue, 2, 516-528. 

Depth Profiling. The quantitative interpretation of AES data requires a knowledge of the distribution of the grain boundary segregants both laterally on the... 

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