Posts tagged Germany
CU scientists discover a new threat from air pollution
Aug 8th
tied to climate change and human health issues
An international research team led by the University of Colorado Boulder and the University of Helsinki has discovered a surprising new chemical compound in Earth’s atmosphere that reacts with sulfur dioxide to form sulfuric acid, which is known to have significant impacts on climate and health.
The new compound, a type of carbonyl oxide, is formed from the reaction of ozone with alkenes, which are a family of hydrocarbons with both natural and man-made sources, said Roy “Lee” Mauldin III, a research associate in CU-Boulder’s atmospheric and oceanic sciences department and lead study author. The study charts a previously unknown chemical pathway for the formation of sulfuric acid, which can result both in increased acid rain and cloud formation as well as negative respiratory effects on humans.
“We have discovered a new and important, atmospherically relevant oxidant,” said Mauldin. “Sulfuric acid plays an essential role in Earth’s atmosphere, from the ecological impacts of acid precipitation to the formation of new aerosol particles, which have significant climatic and health effects. Our findings demonstrate a newly observed connection between the biosphere and atmospheric chemistry.”
A paper on the subject is being published in the Aug. 9 issue of Nature.
Typically the formation of sulfuric acid in the atmosphere occurs via the reaction between the hydroxyl radical OH — which consists of a hydrogen atom and an oxygen atom with unpaired electrons that make it highly reactive — and sulfur dioxide, Mauldin said. The trigger for the reactions to produce sulfuric acid is sunlight, which acts as a “match” to ignite the chemical process, he said.
But Mauldin and his colleagues had suspicions that there were other processes at work when they began detecting sulfuric acid at night, particularly in forests in Finland — where much of the research took place — when the sun wasn’t present to catalyze the reaction. “There were a number of instances when we detected sulfuric acid and wondered where it was coming from,” he said.
In the laboratory, Mauldin and his colleagues combined ozone — which is ubiquitous in the atmosphere — with sulfur dioxide and various alkenes in a gas-analyzing instrument known as a mass spectrometer hooked up with a “flow tube” used to add gases. “Suddenly we saw huge amounts of sulfuric acid being formed,” he said.
Because the researchers wanted to be sure the hydroxyl radical OH was not reacting with the sulfur dioxide to make sulfuric acid, they added in an OH “scavenger” compound to remove any traces of it. Later, one of the research team members held up freshly broken tree branches to the flow tube, exposing hydrocarbons known as isoprene and alpha-pinene — types of alkenes commonly found in trees and which are responsible for the fresh pine tree scent.
“It was such a simple little test,” said Mauldin. “But the sulfuric acid levels went through the roof. It was something we knew that nobody had ever seen before.”
Mauldin said the new chemical pathway for sulfuric acid formation is of interest to climate change researchers because the vast majority of sulfur dioxide is produced by fossil fuel combustion at power plants. “With emissions of sulfur dioxide, the precursor of sulfuric acid, expected to rise globally in the future, this new pathway will affect the atmospheric sulfur cycle,” he said.
According to the U.S. Environmental Protection Agency, more than 90 percent of sulfur dioxide emissions are from fossil fuel combustion at power plants and other industrial facilities. Other sulfur sources include volcanoes and even ocean phytoplankton. It has long been known that when sulfur dioxide reacts with OH, it produces sulfuric acid that can form acid rain, shown to be harmful to terrestrial and aquatic life on Earth.
Airborne sulfuric acid particles — which form in a wide variety of sizes — play the main role in the formation of clouds, which can have a cooling effect on the atmosphere, he said. Smaller particles near the planet’s surface have been shown to cause respiratory problems in humans.
Mauldin said the newly discovered oxidant might help explain recent studies that have shown large parts of the southeastern United States might have cooled slightly over the past century. Particulates from sulfuric acid over the forests there may be forming more clouds than normal, cooling the region by reflecting sunlight back to space.
Most of the laboratory experiments for the study were conducted at the Leibniz-Institute for Tropospheric Research in Leipzig, Germany.
Co-authors on the study include Torsten Berndt and Frank Stratmann from the Leibniz-Institute for Tropospheric Research; Mikko Sipilä, Pauli Paasonen, Tuukka Petäjä, Theo Kurtén, Veli-Matti Kerminen and Markku Kulmula from the University of Helsinki in Finland; and Saewung Kim from the National Center for Atmospheric Research in Boulder. Mauldin also is affiliated with NCAR and the University of Helsinki.
The study was funded by the European Commission Sixth Framework program, the Academy of Finland, The Finnish Center of Excellence, the European Research Council, the Kone Foundation, the Väisälä Foundation, the Maj and Tor Nessling Foundation, the Otto Malm Foundation and the U.S. National Science Foundation.
Dick Winters 1918-2011 American Hero
Jan 12th
Major Dick Winters, who died on January 2 aged 92, was one of the US Army’s most revered service
men of the Second World War; his exploits were later chronicled in the book and television series Band of Brothers.
FROM INDEPENDENT As commander of E Company of the 2nd Battalion, 506th Parachute Infantry Regiment, 101st Airborne Division, Winters and his company proved instrumental on D-Day in ensuring the successful American landings at Utah and Omaha beaches. He would later lead his paratroopers through the forests of France, Belgium and Holland before ending his war in Hitler’s alpine retreat.
The 2nd Battalion’s specific remit for the invasion of Normandy in June 1944 was to secure “Causeway 2”, which linked Utah Beach to the hinterland. The Germans had flooded the fields in between and the planned night-time capture of the causeways was vital in ensuring the eventual success of the amphibious landings.
The operation did not get under way smoothly, as Allied aircraft were faced by withering flak which forced troops to be dropped far away from the target area. Furthermore, the aircraft containing E Company’s Commanding Officer and First Sergeant was shot down, making Winters effective commander.
To make matters worse, Winters had lost his weapon during the drop, and 90 per cent of his men were unaccounted for. But he and 13 other members of “Easy” Company did manage to set up headquarters in a farmhouse, where at daybreak they received intelligence that four German 105mm Howitzers, manned by a full platoon, were firing on Utah Beach; they were ordered to destroy the guns.
In the ensuing attack, Winters ordered half of his squad to unleash an enveloping hail of machine gun fire, while another section of his men took the left flank and hurled hand grenades at the first gun. With this Howitzer duly disabled, the remainder of Easy Company (with the aid of “Dog” Company) made a full assault on the German trenches, spiking the other guns with TNT.
FROM WKIPEDIA
Major Richard “Dick” D. Winters (January 21, 1918 – January 2, 2011)[1] was a United States Army officer and decorated warveteran. He commanded Company “E”, 2nd Battalion, 506th Parachute Infantry Regiment, 101st Airborne Division, during World War II.
Winters parachuted into Normandy in the early hours of D-Day, and fought across France, Belgium, the Netherlands, and eventually into Germany. Later in the war, Winters rose to command the 2nd Battalion. Following the end of hostilities Winters was discharged from the army and returned to civilian life, working in New Jersey.
In 1951, during the Korean War, Winters was recalled to the Army from the inactive list and briefly served as a regimental planning and training officer on staff at Fort Dix, New Jersey. Although issued orders for deployment, he was not sent to Korea. After his discharge he worked at a few different jobs before founding his own company and selling farming products.
Winters was featured in a number of books and was portrayed in the 2001 HBO mini-series Band of Brothers by Damian Lewis. He was a regular guest lecturer at the United States Military Academy at West Point. He retired in 1997.