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Salt Lake City, UT, United States

Tanh Jeazet H.B.,Heinrich Heine University Dusseldorf | Staudt C.,Materials and Systems Research | Janiak C.,Heinrich Heine University Dusseldorf
Dalton Transactions | Year: 2012

Mixed-matrix membranes (MMMs) with metal-organic frameworks (MOFs) as additives (fillers) exhibit enhanced gas permeabilities and possibly also selectivities when compared to the pure polymer. Polyimides (Matrimid®) and polysulfones are popular polymer matrices for MOF fillers. Presently investigated MOFs for MMMs include [Cu(SiF 6)(4,4′-BIPY) 2], [Cu 3(BTC) 2(H 2O) 3] (HKUST-1, Cu-BTC), [Cu(BDC)(DMF)], [Zn 4O(BDC) 3] (MOF-5), [Zn(2-methylimidazolate) 2] (ZIF-8), [Zn(purinate) 2] (ZIF-20), [Zn(2-carboxyaldehyde imidazolate) 2] (ZIF-90), Mn(HCOO) 2, [Al(BDC)(μ-OH)] (MIL-53(Al)), [Al(NH 2-BDC)(μ-OH)] (NH 2-MIL-53(Al)) and [Cr 3O(BDC) 3(F,OH)(H 2O) 2] (MIL-101) (4,4′-BIPY = 4,4′-bipyridine, BTC = benzene-1,3,5-tricarboxylate, BDC = benzene-1,4-dicarboxylate, terephthalate). MOF particle adhesion to polyimide and polysulfone organic polymers does not represent a problem. MOF-polymer MMMs are investigated for the permeability of the single gases H 2, N 2, O 2, CH 4, CO 2 and of the gas mixtures O 2/N 2, H 2/CH 4, CO 2/CH 4, H 2/CO 2, CH 4/N 2 and CO 2/N 2 (preferentially permeating gas named first). Permeability increases can be traced to the MOF porosity. Since the porosity of MOFs can be tuned very precisely, which is not possible with polymeric material, MMMs offer the opportunity of significantly increasing the selectivity compared to the pure polymeric matrix. Additionally in most of the cases the permeability is increased for MMM membranes compared to the pure polymer. Addition of MOFs to polymers in MMMs easily yields performances similar to the best polymer membranes and gives higher selectivities than those reported to date for any pure MOF membrane for the same gas separation. MOF-polymer MMMs allow for easier synthesis and handability compared to pure MOF membranes. This journal is © The Royal Society of Chemistry 2012. Source


An improved method and apparatus for non-destructive measurements of coating thicknesses on a curved surface by measuring components of the microwave energy reflected from the surface. Preferred embodiments of the present invention provide a portable microwave thickness detector with a rounded rocker-type base allowing the microwave beam to be moved through a range of angles with respect to the target surface. An optical alignment system determines when the microwave angle of incidence is at a desired angle when the components of the reflected microwave energy are measured. Preferred embodiments of the present invention also provide a portable microwave thickness detector which maintains a constant standoff distance between the between the microwave detector and the sample to be measured.


An improved method and apparatus for non-destructive measurements of coating thicknesses on a curved surface by measuring components of the microwave energy reflected from the surface. Preferred embodiments of the present invention provide a portable microwave thickness detector with a rounded rocker-type base allowing the microwave beam to be moved through a range of angles with respect to the target surface. An optical alignment system determines when the microwave angle of incidence is at a desired angle when the components of the reflected microwave energy are measured. Preferred embodiments of the present invention also provide a portable microwave thickness detector which maintains a constant standoff distance between the between the microwave detector and the sample to be measured.


Patent
Materials and Systems Research | Date: 2011-11-02

An apparatus for making and using a fastener suitable for use in airplane manufacture or repair that is coated with a pre-mixed moisture cure sealant. The sealant layer is coated with a frangible moisture barrier that will break apart when the fastener is installed, thus exposing the sealant to a moisture source. Once exposed to moisture, the sealant will begin to cure. Preferred embodiments also provide a premature cure indicator that provides a visual indication that the outer moisture resistant layer has been damaged.


Patent
Materials and Systems Research | Date: 2014-11-04

A method and apparatus for the production of nano-sized silicon particles via a low-temperature chemical solid-liquid reaction between a silicon-containing compound and a reducing agent. Embodiments of the present invention provide a production method that is cost-effective, while producing elemental silicon having purity, particle sizes, and stability suitable for energetics applications including solid propulsion additives, igniters, flares, decoys, and liquid fuel catalysts.

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