Results for: ga Search Results
Family Filter:
15:44
People are constantly exposed to low levels of naturally occurring radiation called background radiation. Background radiation comes from cosmic radiation and from radioactive elements in the air, water, and ground. Cosmic radiation is concentrated at the poles by the earth’s magnetic field and is attenuated by the atmosphere. Thus, exposure is greater for people living at high latitudes, at high altitudes, or both and during airplane flights. Terrestrial sources of external radiation exposure are primarily due to the presence of radioactive elements with half-lives comparable to the age of the earth (~4.5 billion years). In particular, uranium (238U) and thorium (232Th) along with several dozen of their radioactive progeny and a radioactive isotope of potassium (40K) are present in many rocks and minerals. Small quantities of these radionuclides are in the food, water, and air and thus contribute to internal exposure as these radionuclides are invariably incorporated into the body. The majority of the dose from internally incorporated radionuclides is from radioisotopes of carbon (14C) and potassium (40K), and because these and other elements (stable and radioactive forms) are constantly replenished in the body by ingestion and inhalation, there are approximately 7,000 atoms undergoing radioactive decay each second. Internal exposure from the inhalation of radioactive isotopes of the noble gas radon (222Rn and 220Rn), which are also formed from the Uranium (238U) decay series, accounts for the largest portion (73%) of the US population's average per capita naturally occurring radiation dose. Cosmic radiation accounts for 11%, radioactive elements in the body for 9%, and external terrestrial radiation for 7%. In the US, people receive an average effective dose of about 3 millisieverts (mSv)/yr from natural sources (range ~0.5 to 20 mSv/yr). However, in some parts of the world, people receive > 50 mSv/yr. The doses from natural background radiation are far too low
24 Jul 2017
0
Share Video

1:09
London ka Ek Aisa System Jis Pr Hr Pakistani Ko Pakistan Mein Krne ka Dil Kare Ga.mp4
24 Jul 2017
51
Share Video

0:56
NO MORE UPSET TUMMY: It’s simple, patented technology in our dietary supplement is a great ally in helping you with stomach or gastrointestinal problems. If you suffer from digestive stress, the addition of proprietary digestive enzymes to probiotics will help you relieve these symptoms and aid you in maintaining healthy bowel regulation.
23 Jul 2017
2
Share Video

0:48
"Help Support Your Immune System With Probiotics*" If you have less-than-optimal digestive health, your "balance" may be off in this crucial area.* Here’s a simple way to help restore it...
21 Jul 2017
6
Share Video

6:21
Fabric Filters (also called baghouses and bagfilters) are air pollution control devices that remove particulate matter from a gas stream by passing the dirty air through a layer of cloth. The particulate matter deposits on the cloth surface and the clean air passes through. Of all the air pollution control technologies, fabric filters are the predominant particulate removal device used in industrial processes today. Fabric Filter bags
21 Jul 2017
7
Share Video

2:27
How to Make POWERFUL Rocket out of 200 L | 55 Gallon Barrel Do not try to repeat any actions shown in this video! It is is very dangerous! Safety is #1 priority! Just watch this video and enjoy :) In this video I show you how to make powerful rocket out of 200 L / 55 gallon barrel. We used сalcium carbide and water. The reaction of calcium carbide with water, producing acetylene and calcium hydroxide CaC2 + 2 H2O → C2H2 + Ca(OH)2. Acetylene is very flammable gas. Even a small spark is enough to set it on fire. If you like this video don't forget to subscribe :)
20 Jul 2017
13
Share Video

3:24
Miniature motors of cable materials, electronic components, paralon, gas lighters and splats
18 Jul 2017
2
Share Video

4:37
Miniature motor dari bahan kabel listrik,korek gas,paralon,komponen elektronik dan spull jahit
18 Jul 2017
4
Share Video

1:40
Miniature motors used cable,gas lighters,paralon,electronic component and spull
18 Jul 2017
5
Share Video

0:59
baloon indonesia
18 Jul 2017
3
Share Video

1:20
Texas Outdoor Patio Center has been proudly serving the DFW and Texas in helping clients find the best grilling equipment. We know every client has a budget in mind so let us find you the best equipment that fits your culinary needs!
17 Jul 2017
10
Share Video

0:45
Here is it again! A lady drives off her car with the gas pump nozzle still attached to the car. What to say, yet another blonde behind the wheels!
14 Jul 2017
317
Share Video