Smoke detector Am-241 activity = 37,000 cps, from my research approximately 1% of this activity is Gamma.
1% is Gamma = 3700 cps (36% of that 1% is at 60 keV)
37 x 36 = 1332 cps = 100% gamma at 60 kev
1295 / 100 = 13.32 = 1%
693 cps was the actual cps in chamber for this peak region
693 / 13.32 = 52% efficiency at 60 keV
Estimated efficiency at 40 keV is approximately 52%.
I used Japanese BecqMoni MCA software to calculate the activity.
Using 52% efficiency at 40 keV.
net count – background = 80039
80039 / 52 = 1,539 (1%)
1,539 x 100 = 153,900 (100%)
Time of test = 79700 seconds
153900 / 79700 = 1.931 cps
82 grams in weight 1000 / 82 = 12.195
1.931 X 12.195 = 23.5 Bq/kg
This may not be an absolute quantification of the scintillator tube’s efficiency at 40 keV, but we are dealing with moss in a large marinelli beaker here. The efficiency of activity is going to be less than the 52% for the Am-241. So the 23.5 Bq/kg activity estimation is probably conservative.
2013/04/15 at 3:44 pm
Soil, Water, and Rain Testing Results
Rainwater capture test 13th, April, 2013
Detected Beryllium Be-7, Lead Pb-210, and Uranium U-235 in local
rain test, Australia
If the large amounts of Beryllium Be-7 being detected in this, and previous tests, has not been created in the upper atmosphere, this means Fukushima is still very unstable, and the molten underground coriums could be still fissioning.
Rain test chart
Roof down pipe filter design.
This is not a test of the activated charcoal in this rainwater roof down pipe filter design, (see link), but the polyester particulate filter I placed before it. The polyester particulate filter was placed in front of the activated charcoal, to trap course material that may get flushed down off the 36 sqm tin roof.
Just thought I would also test the polyester particulate filter, as I usually just test the activated charcoal in this roof down pipe filter experiment. It had been in place for a couple weeks before testing. There had not been much rain through it until recently.
To get better accuracy I placed an Aluminum beta shield in front of the scintillator, during this test. This was to help stop peak position shift caused by a test chambers artifact at 511 keV, and Be-7 being a strong beta emitter.
Beryllium Be-7 has a theoretical back scatter peak at around 166 keV, very close to the 185 kev for Uranium U-235. There is the possibility that it is contributing to the size of the peak at that location. It may also explain the width, and rounding of that peak at around 185 keV.
Please feel free to comment on the test analysis.
In the next couple days I will air dry the activated charcoal filter, and test it.
October 2012, Impact on Australia from the Fukushima Daiichi nuclear power plant accident:
1. Food imported from Japan, page 22.
2. Family living in Fukushima for 150 days, page 32.
3. Vehicles and Military aircraft, including American helicopters, page 28.
4. Mutton Birds Tasmania, page 36.
20th May 2013 – Cherry tomatoes, and asparagus, to be exported from Fukushima Japan to Thailand.
16th January 2013 – Apples, pears, and persimmons, exported to Thailand
5th December 2012 – Sardines Thailand
4th May 2015 – Loophole opens the door to radioactive food in Hong Kong, lawmaker warns
Radioactive contaminated food may have been entering the city unnoticed for years because of deficiencies in safety controls on fresh produce brought in by sea, the South China Morning Post has learned.
But Cheung said while food samples were sent for tests, goods from the same batch could be sold in the market before the results were known.
The question is, are the lax inspection practices in Hong Kong that much different from other places in the world?
27th January 2013 – Tea and spinach imported to Hong Kong
22nd February 2017 – Radioactive boars found in Czech forests 31yrs after Chernobyl disaster
When boars eat radioactive mushrooms, they become radioactive themselves. Boar meat is highly popular in the Czech Republic, so there’s danger of radioactive meat ending up on one’s table.
According to Reuters data, at least 614 wild boars were inspected from 2014 to 2016, and 47 percent of them were radioactive.
6th October 2014 – Radioactivity in Norway’s reindeers hits high
In September, 8200 becquerel per kilo of the radioactive substance Caesium-137 was measured in reindeer from Våga reinlag AS, in Jotunheimen, central Norway.
In comparison, the highest amount at the same place was 1500 becquerel among the reindeer in September 2012.
Lavrans Skuterud said: “This year, there has been extreme amounts of mushroom. In addition, the mushroom season has lasted for a long time. And the mushroom has grown very high up on the mountains.”
Especially the gypsy mushroom (Cortinarius Caperatus) has been a problem. This is a good food mushroom, both for people and animals. But it has one bad trait: It can absorb a lot of radioactivity.