Energy & Green Tech

EXPLAINER: World Cup host Qatar relies on desalination

Arid and surrounded by the salt waters of the Persian Gulf, World Cup host Qatar is among the world's most water-stressed countries. The nation of 2.9 million people has no rivers, and receives less than four inches (10 centimeters) ...

Electronics & Semiconductors

Sulfonamides make robust cathode material for proton batteries

Proton batteries are an innovative and environmentally friendly type of battery in which charge is carried by protons, which are positively charged hydrogen ions. A team of researchers has now developed organic sulfonamides ...

Engineering

World's first LED lights developed from rice husks

Milling rice to separate the grain from the husks produces about 100 million tons of rice husk waste globally each year. Scientists searching for a scalable method to fabricate quantum dots have developed a way to recycle ...

Energy & Green Tech

Efficient, 'green' quantum-dot solar cells exploit defects

Novel quantum dot solar cells developed at Los Alamos National Laboratory match the efficiency of existing quantum-dot based devices, but without lead or other toxic elements that most solar cells of this type rely on.

Engineering

A self-healing sweat sensor

Wearable sensors that track heart rate or steps are popular fitness products. But in the future, working up a good sweat could provide useful information about a person's health. Now, researchers reporting in ACS Applied ...

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Heavy metal (chemistry)

A heavy metal is a member of an ill-defined subset of elements that exhibit metallic properties, which would mainly include the transition metals, some metalloids, lanthanides, and actinides. Many different definitions have been proposed—some based on density, some on atomic number or atomic weight, and some on chemical properties or toxicity. The term heavy metal has been called "meaningless and misleading" in an IUPAC technical report due to the contradictory definitions and its lack of a "coherent scientific basis". There is an alternative term toxic metal, for which no consensus of exact definition exists either. As discussed below, depending on context, heavy metal can include elements lighter than carbon and can exclude some of the heaviest metals. Heavy metals occur naturally in the ecosystem with large variations in concentration. Nowadays anthropogenic sources of heavy metals, i.e. pollution, have been introduced to the ecosystem. Waste derived fuels are especially prone to contain heavy metals so they should be a central concern in a consideration of their use.

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