Crystallinity method

H. P. Meloche, J. M. Ingram, and W. A. Wood, 2-Keto-3-deoxy-6-phosphogluconic aldolase (crystalline). Methods Enzymol. 9 520 (1966). 

Adherent, conformal LPD ceramic film either crystalline (Method 2) or amorphous (Method 1) can be obtained on polyimides. This is in contrast to silanol-bearing surfaces (good for Method 1 only) or sulfonated surfaces (good for Method 2 only). The fact that the polyimides accommodate both titania preparations may be due to the partial hydrolysis of the polymer surface under oxide deposition conditions. This provides a mix of carboxylic acid and amide sites that anchor the titania by a combination of coulombic and chelation-based effects.22 An important lesson of this work is that the interaction of the polymer surface with the deposition solution may create oxide film anchoring sites. This does not negate activating the polymer surface. It recognizes that the polymer surface can react further under the deposition conditions. 

In the 1980s, reviews and textbooks by Kisch (1983) and Frey (1987) summarized the illite crystallinity concept mostly from a petrogenetic point of view. Subsequently, the illite crystallinity method has been incr easingly and extensively applied all over the world as an empirical metamorphic petrological tool (for outstanding examples, see Merriman and Frey 1999). Simultaneously, studies to understand the mineral structural,... 

The starting sol must first of all be a dispersion of amorphous silica ultimate particles. Since the silica in the ultimate product is to be amorphous it is highly important that the sihca particles in the starting sol be free of crystallinity. Methods for determing the presence of crystallinity by x-ray techniques are discussed in R.B. Sosman s The Properties of Silica, Chemical Catalog Company, Inc., New York, 1927, page 207. 

Question by D. H. Tantam, British Oxygen Research and Development Does alloying or dispersion of materials such as bronze dispersion in Teflon have any effect on the crystallinity method described ... 

Our interest in bowlic liquid crystals has arisen from the proposal that bowl shaped molecules may exhibit polar (noncentrosymmetric) organization in the liquid crystalline phases [4, 8, 9]. Indeed bowlic liquid crystals are natural noncentrosymmetric building blocks since a head-to-tail organization maximizes the interactions between bowlic cores. New methodologies for the creation of noncentrosymmetric structures in molecular solids and liquids are critical to the development of new materials with ferroelectric and second order nonlinear optical (NLO) properties [14, 15]. Liquid crystalline methods are particularly attractive since liquid crystalline materials are easily deposited for device construction and are readily aligned. 

SpruieU JE, Clark ES. Unit ceU and crystallinity. Methods Exp Phys 1980 16 1-127. 

Conventional spontaneous Raman scattering is the oldest and most widely used of the Raman based spectroscopic methods. It has served as a standard teclmique for the study of molecular vibrational and rotational levels in gases, and for both intra- and inter-molecular excitations in liquids and solids. (For example, a high resolution study of the vibrons and phonons at low temperatures in crystalline benzene has just appeared [38].)... 

Recently, a unique approach for using the correlation fiinction method has been demonstrated to extract morphological variables in crystalline polymers from time-resolved syncluotron SAXS data. The principle of the calculation is based on two alternative expressions of Porod s law using the fonu of interference fiinction [33. 36]. This approach enables a continuous estimate of the Porod constant, corrections for liquid scattering... 

Because x-rays are particularly penetrating, they are very usefiil in probing solids, but are not as well suited for the analysis of surfaces. X-ray diffraction (XRD) methods are nevertheless used routinely in the characterization of powders and of supported catalysts to extract infomration about the degree of crystallinity and the nature and crystallographic phases of oxides, nitrides and carbides [, ]. Particle size and dispersion data are often acquired with XRD as well. 

Hare D E, Franken J and DIott D D 1995 A new method for studying picosecond dynamics of shocked solids application to crystalline energetic materials Chem. Phys. Lett. 244 224... 

Bruce A D, Wilding N B and Ackland G J 1997 Free energies of crystalline solids a lattice-switch Monte-Carlo method Phys. Rev. Lett. 79 3002-5... 

Ultra-high vacuum (UHV) surface science methods allow preparation and characterization of perfectly clean, well ordered surfaces of single crystalline materials. By preparing pairs of such surfaces it is possible to fonn interfaces under highly controlled conditions. Furthennore, thin films of adsorbed species can be produced and characterized using a wide variety of methods. Surface science methods have been coupled with UHV measurements of macroscopic friction forces. Such measurements have demonstrated that adsorbate film thicknesses of a few monolayers are sufficient to lubricate metal surfaces [12, 181. 

Method(B). Add3g. (3ml.)ofbenzonitrileto50ml.of lo-volumes hydrogen peroxide in a beaker, stir mechanically and add i ml. of 10% aqueous sodium hydroxide solution. Warm the stirred mixture at 40° until the oily suspension of the nitrile has been completely replaced by the crystalline benzamide (45-60 minutes). Cool the solution until crystallisation of the benzamide is complete, and then filter at the pump and recrystallise as above. One recrystallisation gives the pure benza-mide, m.p. 129-130° yield of purified material, 2-2-5 S ... 

Osazone formation. Forms a yellow osazone, m.p. 208° soluble in hot water. See p. 137 for preparation. If examined under the microscope very characteristic clusters of hedge-hog crystals will be seen (Fig. 63(c), p. 139). The difference in the crystalline appearance of lactosazonc and maltosazone should be very carefully noted, as this difference forms the chief and most reliable method of differentiating between these two sugars. 

These are not essential if the acid and amine obtained on hydrolysis are crystalline but crystalline derivatives of the acid and amine can be prepared by the standard methods for acids (p. 349) and amines (pp. 374, 376) respectively. 

In order to dry the crystals, the Buchner funnel is inverted over two or three thicknesses of drying paper (i.e., coarse-grained, smooth surfaced Alter paper) resting upon a pad of newspaper, and the crystalline cake is removed with the aid of a clean spatula several sheets of drying paper are placed on top and the crystals are pressed flrmly. If the sheets become too soiled by the mother liquor absorbed, the crystals should be transferred to fresh paper. The disadvantage of this method of rapid drying is that the recrystallised product is liable to become contaminated with the Alter paper flbre. 

Reflux 1 ml. of the ether with 5 ml. of freshly distilled, constant boiling point hydriodic acid (Section 11,49,2), b.p. 126-128°, for 2-3 hours. Add 10 ml. of water, distil and collect about 7 ml. of liquid. Decolourise the distillate by the addition of a httle sodium bisulphite, and separate the two layers by means of a dropper pipette (Fig. 11,27,1). Determine the b.p. of the resulting iodide by the Siwoloboff method (Section 11,12) and prepare a crystalline derivative (Section 111,42). 

The residue in the flask will contain the sodium (or potassium) salt of the acid together with excess of alkali. Just acidify with dilute sulphuric acid and observe whether a crystalline acid separates if it does, filter, recrystallise and identify (Section 111,85). If no crystaUine solid is obtained, the solution may be just neutralised to phenolphthalein and the solution of the alkali salt used for the preparation of a crystaUine derivative. This wiU confirm, if necessary, the results of hydrolysis by method 1. If the time factor is important, either method 1 or the product of the caustic alkali hydrolysis may be used for the identification of the acid. 

The procedure is not usually applicable to aminosulphonic acids owing to the interaction between the amino group and the phosphorus pentachloride. If, however, the chlorosulphonic acid is prepared by diazotisation and treatment with a solution of cuprous chloride in hydrochloric acid, the crystalline chlorosulphonamide and chlorosulphonanilide may be obtained in the usual way. With some compounds, the amino group may be protected by acetylation. Sulphonic acids derived from a phenol or naphthol cannot be converted into the sulphonyl chlorides by the phosphorus pentachloride method. 

Reduction of methyl orange to />-aminodimethylaniline. Method 1. Dissolve 2 0 g. of methyl orange in the minimum volume of hot water and to the hot solution add a solution of 8 g. of stannous chloride in 20 ml. of concentrated hydrochloric acid until decolourisation takes place gentle boiling may be necessary. Cool the resulting solution in ice a crystalline precipitate consisting of sulphanilic acid and some p-aminodimethylaniline hydrochloride separates out. In order to separate the free base, add 10 per cent, sodium hydroxide solution until the precipitate of tin hydroxide redisaolves. Extract the cold solution with three or four 20 ml. portions of ether, dry the extract... 

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