Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Radioactivity > Radiation > Flashcards

Radiation Flashcards

1
Q

What is an isotope?

A

a nuclide with the same number of electrons and protons but different numbers of neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the difference between a cation and an anion?

A

Cation - positively charged species

Anion - negatively charged species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a radionuclide?

A

an unstable nuclide that emits ionising radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is ionising radiation?

A

radiation that causes ionisation in matter. e.g alpha, beta gamma etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is radiotoxicity?

A

The effect of radio isotopes becoming bound in the body and producing intense biological harm as they decay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the 4 types of decay?

A

Alpha - 2 protons and 2 neutrons emitted by a radionuclide, cant penetrate the skin.
Beta - release of a +/- electron from the nucleus of a radionuclide, may penetrate the skin but stopped by a few mm of metal
Gamma ray - a discrete quantity of electromagnetic energy, without mass or charge, emitted by radionuclide, cannot penetrate lead/thick concrete.
X-ray - a discrete quantity of electromagnetic radiation, without mass or charge, emitted from an x ray machine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a Bacquerel (Bq)?

A

The standard international unit of radiation, corresponding to one nuclear disintegration per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a Gray (Gy)

A

The standard unit of absorbed dose, corresponding to joule per kilogram of material.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a Sievert (Sv)

A

Standard unit of biologically effective dose (absorbed dose (Gy) * biological effectiveness of radiation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the absorbed dose?

A

The quantity of energy imparted by ionising radiation to unit quantity of matter, such as tissue (Gy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the dose equivalent?

A

Absorbed dose weighted for harmfulness of different radiations (Sv)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the effective dose equivalent?

A

dose equivalent weighted for the succeptibility to harm of different tissues. (Sv)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the collective effective dose equivalent?

A

the effective dose equivalent to a group from a source of radiation (man Sv)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does radiation in the UK come from?

A

Natural causes account for 85% - 50% of which is Radon. The remaining is food and drink, cosmic and gamma.
Artificial includes - Nuclear fall out and discharges, consumer products, occupation, medical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the effects of Radon?

A

In open air Radon gas is dispersed, indoors it breaks down into minute solid particles which when breathed into the lungs can increase the risk of lung cancer - 5% of cases in the UK.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

According to UK law what is the acceptable average annual dose of artificial radiation?

A

< 1 mSv

17
Q

What is radon and where are the natural sources of Radon?

A

Radon is a radioactive gas released from the ground. It is found in high concentrations in Cornwall, Devon and Somerset etc due to the geology of the areas.
Indoor concentrations are accepted up to 200 Bq/m3, above which action is required. Averages = 1.3 mSv

18
Q

What is the average annual dose from natural gamma radiation.?

A

0.35 mSv

19
Q

What is the average annual dose from food and drink?

A

0.27 mSv

20
Q

Which food types have high radiation levels.

A

People who eat a large quantity of shellfish are exposed to 220Po radionuclides, along with those who eat large quantity’s of Brazil nuts which have a high proportion of 226/228Ra.

21
Q

What is the average annual dose from cosmic radiation?

A

0.32 mSv

22
Q

What may effect the dose of cosmic radiation?

A

The amount of time spent flying increases the exposure to cosmic radiation with pilots being the most at risk.
Buildings provide partial shielding resulting in those who spend a lot of time indoors being least effected.

23
Q

What are the artificial sources of radiation?

A

Medical - x rays, radionuclides, chemotherapy
Occupation - those who work in mine and nuclear related industries may absorb higher dose.
Fall out - nuclear weapon testing 1960’s, Chernobyl accident 1986
Consumer products - smoke detectors,gas mantles (thromium), watches (tritium)
Nuclear discharge - industries using radioactive materials, water effluents/air emissions

24
Q

How has nuclear fall out trends fallen over time?

A

the annual dose was very low before 1960, however due to nuclear weapon tests in the 1960’s the dose rose to 0.14 mSv in 1963. Here after a PARTIAL NUCLEAR TEST BAN TREATY was signed and the annual dose fell to 0.0006 mSv in 1985. The 1986 Chernobyl accident resulted in a sudden spike. levels have fallen since then.

25
Q

What happened at Chernobyl?

A

1986 - scientists run tests and disable the emergency cooling system.

  • Reactor stabilised at 1000Mw
  • operational error, power falls to 30 Mw
  • power raised to 200Mw
  • increase in coolant flow and decrease in steam pressure casuses reactor to become unstable
  • Power surge to 400,000 Mw in 4 seconds
  • 9 tons of radioactive material released
26
Q

What was the effect of Chernobyl on UK farms?

A

N wales, Lake district and w scotland badly affected (9000 farms) by radioactive material. Restrictions were placed on the sale of sheep from these areas (>1000 Bq/kg). farmers had to rotate the land for grazing to reduce concentrations. 2012 restrictions were lifted.

27
Q

What were the impacts of Chernobyl?

A

Fire fighters - 28 deaths over next 4 months and 19 subsequently. doses of up to 20 000 mSv
Remerdiation workers
large scale evacuation - 45, 000 people.

28
Q

What were the 2 radioactive nuclides released from the Chernobyl accident?

A

131 iodine - 8 day half life

radio-caesium - 30 year half life

29
Q

What are the 3 types of solid waste from nuclear industries?

A

High level - reprocessing of nuclear fuel, highly radioactive, exists as a fluid - converted into glass for storage.
Intermediate level - machinery/metals used within or cladding the nuclear reactor. Stored.
Low level - nuclear workers clothing, stored for period then disposed of.

30
Q

What is RIMNET?

A

Radioactive incident monitoring network.

Radioactivity (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions