E-crystalline

To a solution of 1 g of the mixture of 3-ketal-isomers of compound (II) in 10 cc of acetic anhydride is added a solution of 700 mg of p-toluenesulfonic acid in 7 cc of ecetic anhydride. The reaction mixture is kept at room temperature and under stirring for 5 hours. After some time e crystalline product begins to precipitate and the precipitation is complete by diluting with water. The precipitate is filtered and crystallized from methanol to give 17a-ethynvl-19-nor-testosterone 3,17-diecetate (III), melting point 175°C to 17B°C. 

MW and MWD are very significant parameters in determining the end use performance of polymers. However, difficulty arises in ascertaining the structural properties relationship, especially for the crystalline polymers, due to the interdependent variables, i.e., crystallinity, orientation, crystal structure, processing conditions, etc., which are influenced by MW and MWD of the material. The presence of chain branches and their distribution in PE cause further complications in establishing this correlation. 

Solid cellulose forms a microcrystalline structure with regions of high order, i.e., crystalline regions, and regions of low order that are amorphous. Naturally occurring cellulose (cellulose I) crystallizes monoclinic sphenodic. The molecular chains lay in the fiber direction ... 

Figure. 1. XRD patterns for a) amorphous Fe2oNigo b) crystalline a-Fe c) crystalline y-Ni d) crystalline Fe2oNigo e) crystalline Fe4oNi6o f) crystalline Fego Ni4o.

Often the stability of a drug in the solid state depends on its physical state (i.e., crystalline or amorphous [8]). If freeze-drying produces an amorphous solid and the amorphous form is not stable, then freeze-drying will not provide an acceptable product. 

Halver, J.E. Crystalline aflatoxin and other vectors for trout hepatoma. Res. Rep. US Fish. Wildl. Serv. (1967)... 

In the search for a new class of nanomaterials, i.e. crystalline nanoporous semiconductors, a lot of efforts are made to synthesize new compounds with a zeolite-like open framework structure consisting of typical semiconductor elements like As, Sb, Se, etc.11-41 In 1995 Wang and Liebau reported the preparation and structure of oxoselenoantimonates (III) with a zeolite-like channel structure15 61, which are related to the natural mineral cetineite.171 This mineral with composition (K Na)3+x(Sb203)3(SbS3)(0H) (2.8-x)H20 with x = 0.5, first described in 1987 by Sabelli and Vezzalini181, was found in Le Cetine mine in Tuscany, Italy. 

The overall reaction scheme for dehydration is identical for all butyl alcohols and for both our catalysts, but the relative amounts of various reaction intermediates and the relative values of the rate coefficients for various reaction steps can be dramatically different. Thus, for a given temperature and given catalyst loading in the reactor, and for a given gas-flow rate through the reactor and concentration of butyl alcohol in the gas flow, the observed reaction rates and selectivities with respect to various reaction products can be crucially different for different butyl alcohols and different catalysts (i.e., crystalline HZSM-5 or AAS). 

Svensson E. Crystalline Properties of Starch. Sweden Lund University 1996. [Ph.D. Dissertation],... 

Spin-lattice relaxation measurements (7j) are also common,78 83 though these of course monitor more rapid motions. Spin lattice relaxation times have nevertheless proved a simple but effective means of distinguishing different structural regions within polymer samples, i.e. crystalline and amorphous regions and interfacial regions between crystalline and amorphous parts. 

Above 110 °C, this arrangement becomes mobile, and a smectic C liquid-crystalline phase is entered. Samples cooled down from the isotropic melt (140 °C) show Schlieren and banded textures when viewed under crossed polarizers (Figure 8). These textures look similar to nematic Schlieren textures, but from the X-ray diffraction data it is clear that 12c forms a homeotropically oriented smectic C phase. In a nematic phase, the small-angle diffraction peak would be absent, and a broad scattering feature, a nematic streak , would be observed. Polymer 12c was the first example of a PPE derivative for which three states of matter, i.e. crystalline, thermotropic liquid crystalline, and a highly viscous isotropic liquid, were accessible [46]. 

Confectionery factories normally use sucrose in a number of forms (for examples of particle size and forms commonly used in different confectionery products see Tables 3.2 and 3.3) granulated, i.e. crystalline milled sugar, icing sugar and possibly a 66% sugar syrup (see also... 

If weathering reactions prevail (see Section 5.3), the ions present in water depend on both local soil and mineral composition. The concentration of total dissolved salts (and thus the ionic strength) will be moderate in surface waters, and the main ions will be Ca2+, HCO, and silicates, due to the presence of silica (as silicic acid) and calcite or limestone (i.e., crystalline CaCOj), one of the most common and abundant minerals in soil. 

The cantilevers can be fabricated of any shape and from substantially any material utilized in microelectronics industry, i.e. crystalline or poly-silicon, silicon nitride, silicon oxide, polymer materials (see Note 2). The rectangular shape beams are the most frequently used in biological research. In biological sensors based on the bending method, it is important to have the cantilevers flat and in plane with the base surface. Initial offset or curvature of the beams complicates adjustment of the experimental setup, especially, if working with arrays of cantilever. For this reason, the most common material for cantilevers fabrication nowadays is single crystalline silicon. A large variety of biomolecular interactions have been detected with silicon microcantilevers. 

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