Energy & Green Tech

How long until efficient fuel cells? Ask the experts

In the quest for the perfect alternative for gas-powered vehicles, there have been a lot of contenders over the years. When it comes to public perception, battery electric vehicles (BEVs) are some of the most widely known. ...

Energy & Green Tech

Novel membrane advances low-cost, grid-scale energy storage

Oak Ridge National Laboratory scientists have developed a crucial component for a new kind of low-cost stationary battery system utilizing common materials and designed for grid-scale electricity storage.

Robotics

E-skin able to detect changes in wind, water drops and moving ants

A team of researchers working at the Chinese Academy of Sciences has developed an electronic skin that is sensitive enough to detect changes in air moving, falling drops and moving ants. In their paper published in the journal ...

Machine learning & AI

Machine learning for damaging mutations prediction

Next-generation sequencing technology has ushered in a new era in medicine, making it easier to identify a sequence of nucleotides in DNA or a sequence of amino acids in the proteins of a specific individual and use this ...

Engineering

Semipermeable membrane plays role in drug-sniffing system

A drug -sniffing car kitted out with advanced sensors that can pick up suspicious chemicals has made the news rounds this month; it can smell drugs a quarter of a mile away, said Discovery News.

Hi Tech & Innovation

Authentication path: NEC targets acoustic characteristics of ear

Biometric authentication has frequently made the news—without even knowing any formal definition, we are used to the headlines and the stories about how fingers or eyes can be the keys to gain access to sites and doors, ...

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Membrane

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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