Volume amorphous solvent

The liquefied substance solidifies at —64° C. and boils at —42° C. under 760 mm. pressure, the critical temperature being +138° C.2 One litre of the gas at N.T.P. weighs 3-6715 grams. The solubility in water at 4° C. is 3-77 volumes per unit volume of solvent, whilst at 22-5° C. water dissolves 2-70 times its own volume of the gas.3 The gas is also soluble in molten selenium, being freed on solidification.4 The combination of hydrogen gas and amorphous selenium is accompanied by an absorption of 16-0 Cals, per gram-molecule of hydrogen selenide produced with the use of the more stable monoclinic and metallic forms, the values are 17-0 and 17-4 Cals, respectively.5... 

General Aspects and Heat Treatment Effects. After him formation, for most of the hlms aimed at electronic applications (other than amorphous oxides, such as Si02), the hlms are subjected to a heat treatment process for removal of residual organic species (entrapped solvent as well as the organic constituents associated with the precursor species), densihcation (elimination of residual porosity and structural free volume in the him), and crystallization. 

Evidence was presented that thallous ethylate did not penetrate or alter the crystalline parts of the fiber. Moreover, it was possible to conduct the thallation with different solvents for thallous ethylate. When this was done with normal ethers, the extent of methylation was observed to decrease as the molecular volume of the thallous ethylate solvent increased. These results suggested that accessibility is dependent upon the penetrating power of the ether solvent. Amorphous cellulose was, therefore, defined as the percentage of cellulose wetted by an ether of zero molecular volume and was estimated by determining methylation-molecular volume values for three or more straight-chain ethers, plotting the data and extrapolating to obtain methoxyl content for an ether of zero molecular volume. The amount of cellulose corre-... 

It was also mentioned by McLean et al. that ions and polar solvent molecules must necessarily diffuse across thin amorphous fluorocarbon or interfacial regions between swollen polar domains. However, all of this does not require the need for channels with diameters of 10 A that are coated with SOs groups for long-range transport. In any case, a simple consideration of the steric volume of SOs groups in relation to the size of these channels leads to the conclusion that more than one group would have difficulty fitting into this very small volume. Related... 

In summary, there are at least four ways in which residual moisture in the amorphous state can impact on chemical reactivity. First, as a direct interaction with the drug, for example, in various hydrolytic reactions. Second, water can influence reactivity as a by-product of the reaction, by inhibiting the rate of the forward reaction, for example, in various condensation reactions, such as the Maillard reaction. Third, water acting locally as a solvent or medium facilitating a reaction, without direct participation. Finally, by virtue of its high free volume and low Tg, water can act as a plasticiser, reducing viscosity and enhancing diffusivity [28]. 

Physical properties of polymers, including solubility, are related to the strength of covalent bonds, stiffness of the segments in the polymer backbone, amount of crystallinity or amorphousness, and intermolecular forces between the polymer chains. The strength of the intermolecular forces is directly related to the CED, which is the molar energy of vaporization per unit volume. Since intermolecular attractions of solvent and solute must be overcome when a solute (here the polymer) dissolves, CED values may be used to predict solubility. 

Even if there were no alternatives to chromatography as a method of purifying amorphous API, the number of chromatographic operations should be minimized in order to decrease the volume of organic solvent-containing effluent. It is desirable that the minimum number of chromatographic operations using the most efficient separation mode be incorporated into the process where they are most effective. 

Asphaltene that fraction of petroleum, heavy oil, or bitumen that is precipitated when a large excess (40 volumes) of a low-boiling liquid hydrocarbon (e.g., pentane or heptane) is added to (1 volume) of the feedstock usually a dark brown to black amorphous solid that does not melt prior to decomposition and is soluble in benzene or aromatic naphtha or other chlorinated hydrocarbon solvents. 

Copolymer. The appearence and properties of a particular copolymer obtained depended to a large degree on the type of monomer with which the copolymer was prepared. LS-(methyl acrylate) and LS-(methyl methacrylate) copolymers were brownish amorphous solids. The former was rubbery and moderately hard and the latter was plastic like and harder than the former. At room temperature, both were insoluble in ordinary solvents and quickly swelled in water to about six times in volume. At elevated temperature, the lignin backbone of these two copolymers could be degraded through acid or alkaline hydrolysis. 

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