Characterize the Solids

In order to perform geochemical modeling and interpret the results, the composition and properties of the solid media also should be characterized (Penn et al., 2001 Zhu and Burden, 2001). This unfortunately is often not included in a groundwater study . Much could be said about the millions of dollars expended on groundwater analyses without a single analysis of the minerals at a site. 

Solids mineral identification mineral abundance cation-exchange capacity (CEC) extractable Mn and Fe oxides soil pR acid-generation potential acid-neutralization capacity 

1992 Reed, 1996), and, for fine-grained materials, transmission electron microscopy (TEM) or high resolution TEM (HRTEM see Spence, 1988 Veblen, 1990 Williams and Carter, 1996). 

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When solids react, we would like to know at what temperature the solid state reaction takes place. If the solid decomposes to a different composition, or phase, we would like to have this knowledge so that we can predict and use that knowledge In preparation of desired materials. Sometimes, intermediate compounds form before the final phase. In this chapter, we will detail some of the measurements used to characterize the solid state and methods used to foUow solid state reactions. This will consist of various types of thermal analysis (TA), including differentlEd thermal analysis (DTA), thermogravimetric analysis (TGA) and measurements of optical properties. 

As is well known, the integrand deseribes the solid angle under whieh we see the elementary surfaee from the point p. Respectively, the integral at the right hand side of this equation characterizes the solid angle for the whole surface ... 

The sodium and potassium salts of 11 and 12 and their hydrates have been synthesized and characterized . The solid state structures of anhydrous potassium salt of 12 and its hydrate have been determined by single-crystal X-ray diffraction (Figure 21). Each structure has nearly planar N2O2 groups arranged as blades of a propeller around the main C-H axis. The three blades have similar helicities, or relative orientations. Helicity can be viewed as the relative orientation of the oxygen of the carbon-bound nitrogen with respect to the plane defined by the HCN atoms for the individual blades . ... 

The common aim of the Raman and NIR spectroscopy examples below was to display the API and excipient localization on the tablet surface in order to assess distribution homogeneity and characterize the solid-state properties of the API. 

The fraction of the total volume, Ftot, that is not occupied by solids, the porosity, 0, is often used instead of rsw to characterize the solid-water phase ratio in some environmental systems like sediment beds or aquifers. In the absence of any gas phase, 0 is related to parameters discussed above by ... 

Elemental phosphorus is listed as a hazardous substance and the discharge in excess of 1 pound to surface water is in violation of section 311(b)(3) of the U.S. code of regulations (EPA 1992a). Solid waste containing elemental phosphorus is characterized as a hazardous waste when it passes the characteristic of reactivity stipulated in 40 CFR 261.23. If so characterized, the solid waste must be managed as a hazardous waste (EPA 1992b). 

Tl azide complexes have been observed in solution, though the species are not well characterized. The solid complexes [Ph4As][Tl(N3)4Cl2] and H3[T1(N3)6] have been isolated, the latter being an explosive yellow compound. 

The existence of a current hump near Tc is confirmed by several additional facts. In the first place, these are deduced from the results of the quantitative treatment of the impedance spectra of the HTSC/solid electrolyte system [147]. This approach consists of calculating from the experimental complex-plane impedance diagrams the parameters characterizing the solid electrolyte, the polarization resistance of the reaction with the participation of silver, and the double-layer capacitance (Cdi) for each rvalue (measured with an accuracy of up to 0.05°). Temperature dependence of the conductance and capacitance of the solid electrolyte (considered as control parameters) were found to be monotonic, while the similar dependences of two other parameters exhibited anomalies near Tc- The existence of a weakly pronounced minimum of Cji near Tc, which is of great interest in itself, was interpreted by the authors as the result of sharp reconstruction of the interface in the course of superconducting transition [145]. 

As discussed above, the solid phase for a solute molecule is a fundamental component of a compound s solubility. Consequently, understanding and characterizing the solid phase of a drug, in a given system, is of vital importance from a formulation standpoint. A comprehensive review on the theoretical and practical aspects of solid state chemistry and the significance to the pharmaceutical industry has been given by Byrn et al.. ... 

The concentration-independent term k, will characterize the solid for the particular reaction studies. This intrinsic activity constant will in... 

The spectrum of photons emitted by the solid is then constituted of two parts the first one is characteristic of the elements constituting the solid, the second one characterizes the solid structure. 

Table III. Mean Values of Parameters Characterizing the Solid Residues Obtained Through the Pyrolysis of Old Tires...

We summarize as follows The longitudinal and transverse magnetic susceptibilities characterizing the solid-state process are approximately described by [55]... 

Materials is one area of research which brings together all the physical sciences chemists to synthesize and characterize the solids, physicists to investigate their properties and engineers to fabricate them into useful devices. 

Crystal syntheses do not differ, in their essence, from classical chemical experiments in which molecules are modelled, synthetic routes devised, products characterized and their properties evaluated. However, this typical chemical approach needs, in a sense, to be repeated twice first, in order to prepare the building blocks (whether molecules or ions), and then to arrange the building blocks in a desired way via nucleation, precipitation and crystallization to attain and/or control crystal properties. Obviously, crystallization invariably implies the need to characterize the solid product, often in the form of a polycrystalline powder, for which routine analytical and spectroscopic laboratory tools are much less useful than in the case of solution chemistry. 

High resolution solid-state NMR spectroscopy is also a very powerful method for characterizing the solid structure and the local motion of different solid polymers. We recently characterized the crystalline-noncrystalline structure for different crystalline and liquid crystalline polymers, such as polyolefins [7-12], polyesters [13-15], polyether [16], polyurethanes [17, 18] and polysaccharides, including cellulose [19-29], amylose [30, 31] and dextran [32]. On the basis of these analytical methods, we also investigated the intra- and intermolecular hydrogen bonds of PVA in both crystalline and noncrystalline regions as well as in the frozen solution state. In this chapter. 

The obtained results on chemiluminescence emission from gelatine materials confirmed that this technique can be a useful tool to characterize the solid state of gelatines. It can be applied to different commercial grades and applications for oxidation control during the manufacture and use of gelatines, and is able to quantify the oxidation that is produced by microorganism in the structure of gelatine due to... 

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