Electronics & Semiconductors

Combustion creates Braille display for electronics

Imagine an iPad or a Kindle for the blind, with inflatable Braille that changes shape under a user's touch. A Cornell-led collaboration has made a crucial component for such a technology: A haptic array of densely packed ...


Getting smart about off-grid desalination

Small changes in membrane design can have a large impact on the performance of a new technology developed at KAUST that uses waste heat from solar cells for seawater desalination.

Energy & Green Tech

Hybrid membrane doubles the lifetime of rechargeable batteries

The energy density of traditional lithium-ion batteries is approaching a saturation point that cannot meet the demands of the future—for example in electric vehicles. Lithium metal batteries can provide double the energy ...

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A membrane is a layer of material which serves as a selective barrier between two phases and remains impermeable to specific particles, molecules, or substances when exposed to the action of a driving force. Some components are allowed passage by the membrane into a permeate stream, whereas others are retained by it and accumulate in the retentate stream.

Membranes can be of various thickness, with homogeneous or heterogeneous structure. Membrane can also be classified according to their pore diameter. According to IUPAC, there are three different types of pore size classifications: microporous (dp < 2nm), mesoporous (2nm < dp < 50nm) and macroporous (dp > 50nm). Membranes can be neutral or charged, and particles transport can be active or passive. The latter can be facilitated by pressure, concentration, chemical or electrical gradients of the membrane process. Membranes can be generally classified into three groups: inorganic, polymeric or biological membranes. These three types of membranes differ significantly in their structure and functionality.

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