Researchers have designed a light-harvesting funnel that absorbs sunlight from any direction and concentrates it onto smaller areas, such as high-performance solar cells. By stacking multiple funnels, each tuned to a different ...
(PhysOrg.com) -- Despite ongoing efforts to save the trees, many offices print high volumes of paper documents on a daily basis. Although many companies encourage paper recycling, both disposing of and recycling paper have ...
An international team of paleontologists has discovered remarkable new evidence that pterosaurs, the flying relatives of dinosaurs, were able to control the color of their feathers using melanin pigments.
Paleontology & Fossils
Apr 20, 2022
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423
Glitter is the bane of every parent and primary school teacher. But beyond its general annoyance factor, it's also made of toxic and unsustainable materials, and contributes to plastic pollution.
Materials Science
Nov 11, 2021
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184
A study published the week of July 5 in the Proceedings of the National Academy of Sciences led by Michael Moore at Washington University in St. Louis finds that dragonfly males have consistently evolved less breeding coloration ...
Ecology
Jul 5, 2021
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23
In the frigid waters 1,500 feet below the surface of the Pacific Ocean, hundreds of human-sized Humboldt squid feed on a patch of finger-length lantern fish. Zipping past each other, the predators move with exceptional precision, ...
Plants & Animals
Mar 23, 2020
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427
Scientists from The Australian National University (ANU) and overseas have discovered the oldest colours in the geological record, 1.1 billion-year-old bright pink pigments extracted from rocks deep beneath the Sahara desert ...
Earth Sciences
Jul 9, 2018
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575
Plants and other photosynthetic organisms use a wide variety of pigments to absorb different wavelengths of light. MIT researchers have now developed a theoretical model to predict the spectrum of light absorbed by aggregates ...
General Physics
Jan 12, 2017
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677
A 300 million year-old fossil mystery has been solved by a research team led by the University of Leicester, which has identified that the ancient 'Tully Monster' was a vertebrate—due to the unique characteristics of its ...
Archaeology
Apr 13, 2016
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620
A common blue pigment used in the £5 note could have an important role to play in the development of a quantum computer, according to a paper published today in the journal Nature.
Quantum Physics
Oct 27, 2013
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A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.
Many materials selectively absorb certain wavelengths of light. Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tinting strength relative to the materials it colors. It must be stable in solid form at ambient temperatures.
For industrial applications, as well as in the arts, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade over time, or with exposure to light, while some eventually blacken.
Pigments are used for coloring paint, ink, plastic, fabric, cosmetics, food and other materials. Most pigments used in manufacturing and the visual arts are dry colourants, usually ground into a fine powder. This powder is added to a vehicle (or binder), a relatively neutral or colorless material that suspends the pigment and gives the paint its adhesion.
The worldwide market for inorganic, organic and special pigments had a total volume of around 7.4 million tons in 2006. Asia has the highest rate on a quantity basis followed by Europe and North America. In 2006, a turnover of 17.6 billion US$ (13 billion euro) was reached mostly in Europe, followed by North America and Asia. The global demand on pigments was roughly US$ 20.5 billion in 2009, around 1.5-2% up from the previous year. It is predicted to increase in a stable growth rate in the coming years. The worldwide sales will increase to US$ 24.5 billion in 2015, and reach US$ 27.5 billion in 2018.
A distinction is usually made between a pigment, which is insoluble in the vehicle (resulting in a suspension), and a dye, which either is itself a liquid or is soluble in its vehicle (resulting in a solution). The term biological pigment is used for all colored substances independent of their solubility. A colorant can be both a pigment and a dye depending on the vehicle it is used in. In some cases, a pigment can be manufactured from a dye by precipitating a soluble dye with a metallic salt. The resulting pigment is called a lake pigment.
This text uses material from Wikipedia, licensed under CC BY-SA
