Glasses inhomogeneous

Tokmakoff A and Fayer M D 1995 Homogeneous vibrational dynamics and inhomogeneous broadening in glass-forming liquids infrared photon echo experiments from room temperature to 10 KJ. Chem. Phys. 103 2810-26... 

Lee H W H, Walsh C A and Payer M D 1985 Inhomogeneous broadening of eleotronio transitions of ohromophores in orystals and glasses analysis of hole burning and fluoresoenoe line narrowing experiments J. Chem. Phys. 82 3948-58... 

In the second procedure, calcium nitrate was replaced by calcium alkoxide (60). Calcium and sificon alkoxides have very different rates of hydrolysis. To avoid the production of inhomogeneities, a slow and controlled hydrolysis of a mixture of sificon, calcium, and phosphorous alkoxide was performed. The resulting materials were highly homogenous, and monolithic pieces could be produced. The bioactivity of the gel-derived materials is equivalent or greater than melt-derived glasses. 

Recently, many experiments have been performed on the structure and dynamics of liquids in porous glasses [175-190]. These studies are difficult to interpret because of the inhomogeneity of the sample. Simulations of water in a cylindrical cavity inside a block of hydrophilic Vycor glass have recently been performed [24,191,192] to facilitate the analysis of experimental results. Water molecules interact with Vycor atoms, using an empirical potential model which consists of (12-6) Lennard-Jones and Coulomb interactions. All atoms in the Vycor block are immobile. For details see Ref. 191. We have simulated samples at room temperature, which are filled with water to between 19 and 96 percent of the maximum possible amount. Because of the hydrophilicity of the glass, water molecules cover the surface already in nearly empty pores no molecules are found in the pore center in this case, although the density distribution is rather wide. When the amount of water increases, the center of the pore fills. Only in the case of 96 percent filling, a continuous aqueous phase without a cavity in the center of the pore is observed. 

When liposomes are prepared from a molecular mixture of lipid components it is important that all lipids be homogeneously dissolved in an organic solvent in order to obteiin bilayers with evenly distributed lipids after hydration. For example, the solubilities of phosphatidylcholine and cholesterol in chloroform are similar their solubility in benzene differs. Upon removal of benzene from the lipid solution an inhomogeneous lipid film is formed on the glass wall and... 

Thus, we considered a number of examples of application of the sensor technique in experiments on heterogeneous recombination of active particles, pyrolysis and photolysis of chemical compounds in gas phase and on the surface of solids, such as oxides of metals and glasses. The above examples prove that, in a number of cases, compact detectors of free atoms and radicals allow one to reveal essential elements of the mechanisms of the processes under consideration. Moreover, this technique provides new experimental data, which cannot be obtained by other methods. Sensors can be used for investigations in both gas phase and adsorbed layers. This technique can also be used for studying several types of active particles. It allows one to determine specific features of distribution of the active particles along the reaction vessel. The above experiments demonstrate inhomogeneity of the reaction mixture for the specified processes and, consequently, inhomogeneity of the... 

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