Navigation Links
Accurate measurement of radioactive thoron possible at last
Date:3/7/2011

metrologists speak of a primary standard like the one that already exists for Rn-222, was considered impossible for a long time, because thoron has a relatively short half-life of only 55 seconds. The PTB team finally had a brilliant idea:

The core of the primary standard is a test container which is filled with a defined amount of thoron. In view of the short half-life, a closed container, such as for radon, did not come into question, as the activity would quickly decay in that, in a short time. For this reason the scientists developed a circuit system that constantly introduces newly produced thoron with a high flow air stream and keeps the activity in the container constant.

The production and the accurate measurement of the activity which was fed in, was a metrological challenge. It was possible through a novel measuring arrangement called the thoron emanation measuring facility (TEM). The activity thereby comes from a thorium (Th-228) preparation which continually produces thoron. A constant, strong air stream transports the thoron into the test container. The tough nut that had to be cracked was: how much thoron is transported away and how much stays in the source? The PTB team finally succeeded in determining this ratio to one tenth of a per cent exactly.

Parallel to operating the TEM, the measuring instrument to be calibrated can be connected to the test container. As a rule, all the connected devices show more or less different results. You might even have a factor of 4! The manufacturers then receive a correction factor from PTB with which they have to multiply the measurement result to get to the correct result.

As more and more geological and epidemiological studies in Asia, Europe and Latin America are focussed on thoron (to which little attention had been paid to date), the newly set up measuring arrangement at PTB is constantly fully booked by international customers.


'/>"/>

Contact: Dr. Anntette Roettger
annette.roettger@ptb.de
49-531-592-6130
Physikalisch-Technische Bundesanstalt (PTB)
Source:Eurekalert

Page: 1 2

Related medicine news :

1. Rapid Flu Test Most Accurate for Young Kids
2. LifeScan Recalls Specific Lots of Consumer and Professional OneTouch(R) SureStep(R) Test Strips Due To Inaccurate Readings at High Levels
3. Study: Mechanomyography to be accurate in detecting nerves during minimally invasive spine surgery
4. Whole body MRI is highly accurate in the early detection of breast cancer metastases
5. Innovative Technology Developed at AGH Accurately Monitors Healthcare Professionals' Handwashing Practices, Study Shows
6. Survey: Many Young Women Lack Accurate Information about STDs
7. Study finds cancer information on Wikipedia is accurate, but not very readable
8. New formula gives first accurate peak heart rate for women
9. Latino children with asthma less accurate in determining their lung function
10. Experimental TB Test Called Fast and Accurate
11. Blood test accurately predicts death from prostate cancer up to 25 years in advance
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/24/2014)... The North American Omega 3 & Structured Lipids ... lipids market in North America with analysis and forecast of ... from around $762.4 million in 2012 to $1,117 million by ... , Browse through the TOC of the North American Omega ... of the in-depth analysis provided. This also provides a glimpse ...
(Date:7/24/2014)... 5 percent of all prenatal ultrasounds uncover antenatal ... prenatal abnormality in the United States. Many children ... antibiotics for the first few years of life ... urinary tract infections. Until recently, however, little evidence ... which involves considerable cost and inconvenience for families. ...
(Date:7/24/2014)... further and faster, according to a new study published ... drugs to tackle melanoma, the most deadly form of ... University of Manchester found that some melanoma cells are ... the surrounding tissue, while other melanoma cells are the ... a tumour, the faster growing cells ,piggy-back, along with ...
(Date:7/24/2014)... Cuyahoga County high school students are smoking tobacco products ... according to new data from the Prevention Research Center ... In 2013, more than 22 percent, or one in ... product within the prior 30 days. , Equally surprising ... and hookahs, or water pipes, more than cigarettes ...
(Date:7/24/2014)... but recessions decrease it. Sound paradoxical? Researchers thought ... have shown that employees who lose their jobs ... have shown, unexpectedly, that population mortality actually declines ... and the University of Michigan in Ann Arbor ... findings. , Using a nationally representative panel of ...
Breaking Medicine News(10 mins):Health News:North America Omega 3 & Structured Lipids (Nutraceuticals) Market is Expected to Reach $1,117 million in 2018 - New Report by MicroMarket Monitor 2Health News:North America Omega 3 & Structured Lipids (Nutraceuticals) Market is Expected to Reach $1,117 million in 2018 - New Report by MicroMarket Monitor 3Health News:North America Omega 3 & Structured Lipids (Nutraceuticals) Market is Expected to Reach $1,117 million in 2018 - New Report by MicroMarket Monitor 4Health News:North America Omega 3 & Structured Lipids (Nutraceuticals) Market is Expected to Reach $1,117 million in 2018 - New Report by MicroMarket Monitor 5Health News:Continuous antibiotics not necessary for many children with common prenatal abnormality 2Health News:Continuous antibiotics not necessary for many children with common prenatal abnormality 3Health News:Piggy-backing cells hold clue to skin cancer growth 2Health News:Cuyahoga County high school students smoking at the same rate as adults 2Health News:Cuyahoga County high school students smoking at the same rate as adults 3Health News:Cuyahoga County high school students smoking at the same rate as adults 4Health News:Joblessness could kill you, but recessions could be good for your health 2Health News:Joblessness could kill you, but recessions could be good for your health 3
... turning their backs on tanning amid growing concerns over skin ... survey shows that teenagers are resisting the urge to tan ... 5,073 Australian adults and 699 Australian teenagers aged 12 to ... that 68 % of those aged 12-17 said they had ...
... University have found a new model that shows how ... in the presence of microenvironment of tumor cells. // ... skin cell to malignant cell is understood with the ... offer new insights into the influence of the tumor ...
... the developing fetus, a womb confers safety and security to ... a womb is even necessary for normal brain development. // ... found to have a poor brain development when compared to ... done regarding brain development of babies born around 26 weeks ...
... bottle-feeding may impose an increased risk of iron deficiency ... American children) according to // a new study by ... Wisconsin. , ,"This is the first study that ... prolonged bottle-feeding and iron deficiency, among a nationally representative ...
... in the UK has revealed that smokers are unconcerned with ... particular they seemed to be aware of the damage // ... lip and even the teeth, but were strangely reluctant to ... oral and maxillofacial surgeons, who are launching a massive awareness ...
... across the walls of a patient's room have been ... hypertension and rheumatic complaints, a study says.//,A study group ... kept in medicated rooms were cured in shorter less ... study involved 36 patients, of whom 19 were kept ...
Cached Medicine News:Health News:Aussie teens applauded for declining sun tan 2Health News:New Model for understanding Tumor Metastasis 2Health News:Brain development compromised in premature babies 2Health News:Iron deficiency found in children with prolonged bottle feeding 2Health News:Now medicated coir to cure ailments 2
(Date:7/24/2014)... 2014  To help health care organizations better ... impact patient care and the bottom line, Novation ... "Innovations in Cardiovascular Devices."  The ... details on promising new technologies that can help ... these options impact the supply chain.   According to ...
(Date:7/24/2014)... , July 24, 2014  Blueprint Medicines (Blueprint), a ... defined cancer patients, today announced the appointment of ... Albers joins Blueprint from Algeta ASA, where he served ... to the acquisition by Bayer. Mr. Albers succeeds ... and Partner at Third Rock Ventures, who will remain ...
(Date:7/24/2014)... 2014  Bayer HealthCare today announced positive results ... 15% foam formulation of its compound azelaic acid ... and pustules of rosacea. An AzA foam formulation ... currently available AzA gel formulation. Papulopustular rosacea is ... pustules) as well as erythema (redness) on the ...
Breaking Medicine Technology:New Novation CV Watch Shows Recent Technology Innovations Could Drive Cardiovascular Product Costs Up by as Much as 35 Percent 2New Novation CV Watch Shows Recent Technology Innovations Could Drive Cardiovascular Product Costs Up by as Much as 35 Percent 3Blueprint Medicines Appoints Jeffrey Albers as Chief Executive Officer 2Phase III Investigational Trial of Azelaic Acid 15% Foam Meets Both Co-Primary Endpoints in Subjects with Papulopustular Rosacea 2Phase III Investigational Trial of Azelaic Acid 15% Foam Meets Both Co-Primary Endpoints in Subjects with Papulopustular Rosacea 3
... YORK, Nov. 5 Immtech Pharmaceuticals,Inc. (Amex: ... $5.1 million from a,scientific consortium led by the ... received funds from The Bill & Melinda Gates ... African sleeping,sickness (trypanosomiasis) and leishmania. This grant is ...
... experts from the,Alzheimer,s Foundation of America (AFA) today ... in light of research,indicating that cases of mild ... that early diagnosis can lead to appropriate treatment ... chief executive officer, and J. Wesson Ashford,M.D., Ph.D., ...
Cached Medicine Technology:Immtech Receives $5.1 Million to Further African Sleeping Sickness Clinical Trials 2Immtech Receives $5.1 Million to Further African Sleeping Sickness Clinical Trials 3Experts Call for Widespread Use of Memory Screenings and Emphasize Value of Early Detection of Dementia 2Experts Call for Widespread Use of Memory Screenings and Emphasize Value of Early Detection of Dementia 3Experts Call for Widespread Use of Memory Screenings and Emphasize Value of Early Detection of Dementia 4
... throughput reading of entire racks. Its scanner-based image ... and reads in approximately 10 seconds per rack. ... and a list of ActiveX controls is provided ... includes a USB HP Scanner and software. Compatible ...
... with powder-coated steel legs. Height ... in hundreds of sizes and ... light fixtures and ionizing equipment. ... custom building to meet special ...
Round, height-adjustable, steel laboratory stools with small footprint for small spaces • Choose options like different height-adjustment mechanism or paint finish. • your choice of color...
... This BioSafe room is configured specifically ... and chemical analysis. Panels are precision-joined ... easy to wipe down and disinfect. ... double-wall panel design creates strong, rigid ...
Medicine Products: