Glass, organic borosilicate glasses

Organic Solvents and Lipid Solutions. Reagent grade solvents were distilled before use. The lipids were dissolved in chloroform-methanol (85 to 15 v./v.) at a concentration of about 0.5 mg. per ml. and stored in glass-stoppered borosilicate glass tubes for not longer than 5 days at 5°C. Lipid mixtures were freshly prepared from the stock solutions of the individual components. 

A convenient method to introduce organic functions into inorganic networks is the use of substituted siliceous acid esters and the sol-gel route. The basic reactions, therefore, are given in Equations 1 and 2. Equation 1 describes the sol-gel reaction to a borosilicate glass. 

Borosilicate glass and ceramics are inert materials and have great chemical stability the weak point about glass, however, is its fragility. Glass can be used for both organics and inorganics, but one should be mindful of the fact that it is a potential source of boron and silicon and cannot be used if these elements are to be determined. 

Chemical Resistance—completely closed-cell, foamed borosilicate glass block is resistant to weak bases, all organic and almost all inorganic acids. It is not resistant to hydrofluoric acid, acid fluorides or strong alkalies. 

We found that seawater solutions pre-acidified with nitric acid to 1.2-1.3% by volume and containing 5-50 ng Hg/1. could be stored in Teflon bottles for at least one month without significant loss of mercury. Therefore, we used Teflon bottles for storage containers and collection samplers for surface seawater. We found borosilicate glass containers to yield occasional high blanks. Moreover, the presence of either volatile organic plasticizer material or polyethylene residue leached by the acidified seawater solution renders polyethylene containers unsuitable. 

Figure 2.16 Photograph of a 1mm diameter thin walled (10 pm thick) borosilicate glass capillary, glued with melted wax into a brass holder for clamping to a spinner. The sample is a white organic compound, but exposure to an intense X ray beam turns it yellow. This sample was translated between successive data collection scans to avoid radiation damage, resulting in the striped appearance.

GMF FILTERS Resistant to weakening or disruption of the fibrous matrix by inorganic or organic solutions and has a broad chemical compatibility. Made of borosilicate glass microfibers. Presterilized by gamma irradiation. 

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