Led by Max Zhang, assistant professor of mechanical and aerospace engineering, the study indicates that such measures as regulating traffic density and encouraging public transportation can have a significant impact on local air quality.
“We hope our study can help or advise local regulators and policymakers to adopt long-term sustainable emission controls to improve air quality,” Zhang said. “That’s our mission.”
Published online July 11 in the journal Atmospheric Environment, the study was based on air quality readings before, during and after the Olympics. Leading up to the Olympics, the Chinese government barred more than 300,000 heavy-emission vehicles – mostly trucks – from the roads. The city also implemented rules in which only some people were allowed to drive on certain days based on their license plate numbers. As a result, close to 2 million vehicles were pulled from the roads. Other mandates involved halting construction and decreasing the use of coal in favor of natural gas for electricity.
In 2007 and 2008, the researchers collected air quality data from equipment installed at two elevations on a building in the heart of Beijing.
They also tracked emissions from vehicles in different areas of the city by following randomly selected cars and trucks in a minivan equipped with sensitive instruments for detecting carbon particles, including carbon monoxide, carbon dioxide and black carbon, or soot.
Among the researchers’ conclusions: Black carbon pollution is significantly greater at ground level than at higher elevations, and diesel trucks are a major source of black carbon emission during the summer in Beijing. These particles are not only harmful to the lungs, but are also known to be a global warming compound, Zhang said.
The researchers found that car emissions of black carbon were down 33 percent in 2008 compared with their 2007 readings. Carbon dioxide decreased 47 percent, and ultrafine carbon-based particles – those that measure less than 100 nanometers – decreased 78 percent.The sharp drops were most likely due to a new emission standard implemented in Beijing in 2008, in which all new registered vehicles as well as gasoline and diesel fuel engines were required to achieve emissions standards equivalent to European Union regulations. A similar standard was mandated starting in June 2008 for 20,000 buses and 66,000 taxies. The improved fuel quality probably enhanced the performance of engines and catalytic converters, the researchers reported.
“We are showing what the city can do if they are determined to improve air quality,” Zhang said.
The study, whose first author was graduate student Xing Wang, was funded by the U.S. Environmental Protection Agency and Cornell’s Jeffrey Sean Lehman Fund for Scholarly Exchange with China.
Blaine Friedlander | Newswise Science News
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences