The concentration of certain toxic organic chemicals in waterway sediments can be reduced by 83 percent using electron beams—the same technology already used to decontaminate mail—scientists from the National Institute of Standards and Technology (NIST) and the University of Maryland will report in the Sept. 1 issue of Environmental Science & Technology. In an additional series of laboratory experiments, the team found that ultraviolet light also can substantially reduce the concentration of these chemicals.
The results are significant because sediments, soupy mixtures of water and particles of various sizes, arenotoriously difficult and expensive to decontaminate. Further, electron beams and ultraviolet light effectively detoxified the banned chemicals known collectively as polychlorinated biphenyls, or PCBs, which can get into the food chain and increase the risk of cancer in humans. Waterways such as the Hudson River have bottom sediments heavily contaminated with PCBs. However, whether electron beams and ultraviolet light are practical decontamination techniques will depend on cost-effectiveness comparisons to existing methods, such as chemical treatment and incineration. In addition, issues such as availability of electron beams will need to be resolved. The scientists used a beam at the University of Maryland for the recent studies.
Electron beams and ultraviolet light remove chlorine ions (charged atoms) from PCBs, which reduces toxic-ity and enhances prospects for biodegradation of the remaining material by living organisms. The scientists evaluated the effectiveness of the treatment methods in removing PCBs from a NIST Standard Reference Material containing sediments with carefully measured amounts of contaminants. Research continues on additives and conditions that might enhance the decontamination processes. The research is funded by NIST, the university, and the Maryland Water Resources Center.
Laura Ost, | NIST
Value from wastewater
16.08.2017 | Hochschule Landshut
Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences