New findings help in protecting divertor without degrading core plasma
2021-05-20
(Press-News.org) The high-power and long-pulse operation of tokamak will cause excessive particle flux and heat load on the divertor target plate. The surface of the target plate will be subject to intense sputtering, and the thermal load of the target plate will exceed the material/component limit.
The sputtered atoms generated by the damage of the target plate may be transported to the core plasma, degrading the quality of the fusion plasma and increasing the difficulty of plasma stability control.
Recently, the EAST group of Institute of Plasma Physics, Hefei Institutes of Physical Science (HFIPS), reported their new findings about the influence of different impurity gases (Ar and Ne) seeding on the divertor plasma state and the core plasma confinement.
Their study was published in Nuclear Fusion on April 29.
"We conducted the experiment with the upper single null configuration with ITER-like tungsten divertor, and achieved stable partial energy detachment around the upper outer strike point," said YANG Zhongshi, a specialist in nuclear physics, "whether we seeded Ne or Ar from the upper outer divertor target, the result was prominent." In this way, they also observed that the material sputtering was well suppressed.
However, there was no detachment on the upper inner divertor with Tet around strike point remaining > 10 eV with either Ar or Ne seeding from the upper outer divertor. Ar seeding always causes confinement degradation in the partial energy detachment state. "There is a slight confinement improvement with Ne seeding." Said YANG.
These results provide a feasible physical experiment program for realizing and maintaining the steady-state plasma under the conditions of the tungsten divertor, solving the problem of steady-state thermal load and sputtering of the target plate, and ensuring the stable operation of the EAST under high-power long-pulse conditions.
INFORMATION:
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-05-20
"Pretty" parrots are more likely to be snatched up for Indonesia's illegal wildlife trade, a new study reveals.
The findings not only expose the key drivers behind the country's illegal trade in these birds, but offer lessons for the potential emergence and spread of infectious diseases that jump from animals to humans - like COVID-19 and avian flu.
The study, involving researchers from The Australian National University (ANU), analysed two decades worth of data on the illegal trade of parrots in Southeast Asia.
The researchers found some key reasons parrots ...
2021-05-20
E-scooters as a new micro-mobility service: SMART researchers explore the potential of e-scooter sharing as a replacement for short-distance transit in Singapore
SMART researchers found that e-scooters are not only a last-mile solution to complement transit services, but also provide a mobility service for short-distance transit trips
- Through a stated preference survey and mixed logit models, SMART researchers found that fare, transit transfer, and transit walking distance are significant factors driving the use of e-scooters as an alternative means of transit. The uncertainty is higher in predicting e-scooter usage preferences of male, young and high-income ...
2021-05-20
Tsukuba, Japan - Warm, dry wind events blowing down from mountain slopes, called foehns, are a meteorological phenomenon typically associated with the European Alps or the Rocky Mountains of North America. However, in recent decades, foehn winds in Japan have caused record-breaking hazardous warm weather events, bringing renewed interest in the behavior of these winds in this part of the world.
In a new study published in the International Journal of Climatology, a research team led by the University of Tsukuba has presented the first comprehensive climatological study of Japan's south foehn, a windstorm that originates from the Backbone Mountain Range and is observed along the coast of the Sea of Japan, including in the Toyama ...
2021-05-20
Microfluidic chips hold great promise for unparalleled applications in pathogen detection and cancer diagnosis. Such devices often require nanoscale thin films for the filtering of liquid samples, as well as power devices or chemical stimulus that control its flow direction. However, many challenges still remain with most precedent mechanisms, including complicated fabrication processes, limitations of materials, and undesired damage on samples.
A research team, led by Professor Taesung Kim in the Department of Mechanical Engineering at UNIST presented the ...
2021-05-20
Everything from the production of fertilisers and plastics, to liquid fuels and pharmaceuticals require an important chemical reaction known as hydrogenation. This is a process involving the addition of hydrogen to unsaturated chemical bonds. Enhancing the rate of hydrogenation can lead to higher yields for industries and lower environmental impacts.
Now, a team of scientists, led by Associate Professor Yan Ning from the Department of Chemical and Biomolecular Engineering at the National University of Singapore (NUS), has come up with a method to increase the rate of ethylene ...
2021-05-20
People with Alzheimer's disease (AD) are less likely to have cataract surgery than people without Alzheime's disease. The procedure rate starts to decrease already one year after the diagnosis, according to a new study from the University of Eastern Finland.
The lower likelihood of cataract surgery among people with cognitive disorders has been reported previously. This study is the first to report an association between the AD diagnosis and a lower incidence of cataract surgery, and a decrease in the procedure rate related to the time since the diagnosis.
The decrease in the incidence of cataract surgery among people with newly diagnosed AD is concerning because the benefits of this low-risk procedure would probably be similar for people with and without ...
2021-05-20
DALLAS - May 20, 2021 - An experimental drug that has shown promise in protecting healthy tissue from collateral damage caused by radiation therapy for cancer also appears to enhance radiation's capacity to kill tumors, a new study led by UT Southwestern scientists shows. The findings, published online in Science Translational Medicine, could provide a much-needed boost to the radiation treatments used against a variety of tumor types.
The drug, avasopasem manganese (AVA), has already shown promise in clinical trials to prevent a side effect known as acute mucositis. This condition commonly occurs in head and ...
2021-05-20
Elephants and lions are iconic species that help raise substantial funds for conservation. However, they also pose significant threats to people, crops, and livestock, and are themselves threatened with extinction.
Areas at severe risk are identified
In a new article published in the journal Nature Communications, scientists have identified the areas that are most at risk for conflicts between humans and elephants and lions in Africa. They also estimated the associated return on investment of building and maintaining high-quality fences, which are used to reduce conflict between humans and wildlife.
Associate Professor Enrico Di Minin, who is the lead author of this article and leads the Helsinki Lab of Interdisciplinary Conservation Science ...
2021-05-20
Great tits living in cities are genetically different from great tits in the countryside. This is what researchers have found in a unique study, where they examined populations of great tits in nine large European cities.
The researchers compared the city bird genes with the genes of their relatives in the countryside. It did not matter if the great tits lived in Milan, Malmö or Madrid: in order to handle an environment created by humans, the birds evolved in a similar way.
Different gene types linked to important biological functions such as cognition and various behaviours regulated by serotonin, including aggression and circadian rhythms, were found to have been selected and passed on from generation to generation. In rural populations, these behaviours are also ...
2021-05-20
When the United States issued national stay-at-home guidelines in March 2020 in response to the COVID-19 pandemic, mobility across the country dropped significantly. New research from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) demonstrates that people may be inclined to change their behavior in response to national guidelines, more than state and local policies.
"When the next pandemic hits, we need to know what kind of policies are going to have the biggest impact on human behavior and health," said Marianna Linz, Assistant Professor of Environmental Science and Engineering and of Earth and Planetary Sciences at SEAS and senior author of the paper. "While specific, local ...
LAST 30 PRESS RELEASES:
[Press-News.org] New findings help in protecting divertor without degrading core plasma
