c**i
发帖数: 6973 | 1 李大同, 点评中国: 谣言止于公信. BBC Chinese, July 27, 2009.
http://news.bbc.co.uk/chinese/simp/hi/newsid_8170000/newsid_8170700/8170799.stm
My comment:
(a) The commentary started with “我们小时候都读过《咕咚来了》的童话.”
(b) Cobalt-60 creates beta decay. Beta particles can be stopped by a sheet
of aluminum that is 2 to 3 mm thick. Perhaps because the author, Mr. 李大同,
was starved of information--Chinese government has said little about the
incident—his commentary states, “6月14日15时，辐照室内接受辐照加工的辣椒粉
由于放射源的长时间照射，温度过高自燃。” Beta rad |
d****d
发帖数: 2919 | 2 瞎说，钴６０明显是gamma源
同,
瞎说，钴６０明显是gamma源
cause
【在 c**i 的大作中提到】
: 李大同, 点评中国: 谣言止于公信. BBC Chinese, July 27, 2009.
: http://news.bbc.co.uk/chinese/simp/hi/newsid_8170000/newsid_8170700/8170799.stm
: My comment:
: (a) The commentary started with “我们小时候都读过《咕咚来了》的童话.”
: (b) Cobalt-60 creates beta decay. Beta particles can be stopped by a sheet
: of aluminum that is 2 to 3 mm thick. Perhaps because the author, Mr. 李大同,
: was starved of information--Chinese government has said little about the
: incident—his commentary states, “6月14日15时，辐照室内接受辐照加工的辣椒粉
: 由于放射源的长时间照射，温度过高自燃。” Beta rad
|
c**i
发帖数: 6973 | 3 I did double check.
Anyway, gamma ray can be stopped with a thick wall.
【在 d****d 的大作中提到】
: 瞎说，钴６０明显是gamma源
:
: 同,
: 瞎说，钴６０明显是gamma源
: cause
|
i**n
发帖数: 1436 | 4 废话，关键是问题是铅版有多厚。有个词叫做shielding。还来个词叫做stopped，
holly cow! why somebody refuses to be a chinese while uses chinglish?
【在 c**i 的大作中提到】
: I did double check.
: Anyway, gamma ray can be stopped with a thick wall.
|
d****d
发帖数: 2919 | 5 你哪儿check的？
别告诉我这种东西都到wiki上去check。。。
直接告诉你吧，钴６０到镍６０确实是beta decay，
不过它作为放射源的主要应用就是那两个gamma。。
至于beta么，别说你前面说的用铝薄，空气就把它干掉了。。
【在 c**i 的大作中提到】
: I did double check.
: Anyway, gamma ray can be stopped with a thick wall.
|
d****d
发帖数: 2919 | 6 这个又是直接拿墙shielding掉了就完了。。。
否则就没有放射性危害这么一会事了。
放射性对公众的危害主要是反射性沾染，就是放射物质粉末泄露，通过水源，食物直接
进入人体，甚至被呼吸进去，造成长期伤害。
这个你怎么shielding？
btw，相比alpha和beta，gamma辐射的伤害微乎其微。
【在 i**n 的大作中提到】
: 废话，关键是问题是铅版有多厚。有个词叫做shielding。还来个词叫做stopped，
: holly cow! why somebody refuses to be a chinese while uses chinglish?
|
c**i
发帖数: 6973 | 7 (1) I was assuming that Chinese in the county realized that the radioactive
source was Cobalt-60, emitted beta particles and confined inside a building.
Therefore, radioactive dusts were not an issue.
(2) Then, radiation from the cobalt-60 could not travel far.
FAQs About Radiation Protection
http://www.nrc.gov/about-nrc/radiation/related-info/faq.html
("Alpha and beta particles do not travel far at all, and they are easily
blocked.")
(3) I cannot find argument for or against your statement that
【在 d****d 的大作中提到】
: 这个又是直接拿墙shielding掉了就完了。。。
: 否则就没有放射性危害这么一会事了。
: 放射性对公众的危害主要是反射性沾染，就是放射物质粉末泄露，通过水源，食物直接
: 进入人体，甚至被呼吸进去，造成长期伤害。
: 这个你怎么shielding？
: btw，相比alpha和beta，gamma辐射的伤害微乎其微。
|
d****d
发帖数: 2919 | 8 算了吧，钴60是典型的gamma源都不知道，还beta beta的。。
radioactive
building.
【在 c**i 的大作中提到】
: (1) I was assuming that Chinese in the county realized that the radioactive
: source was Cobalt-60, emitted beta particles and confined inside a building.
: Therefore, radioactive dusts were not an issue.
: (2) Then, radiation from the cobalt-60 could not travel far.
: FAQs About Radiation Protection
: http://www.nrc.gov/about-nrc/radiation/related-info/faq.html
: ("Alpha and beta particles do not travel far at all, and they are easily
: blocked.")
: (3) I cannot find argument for or against your statement that
|
c**i
发帖数: 6973 | 9 All of the following is for the reference of "dumand" in his various
postings. I trust the issues may now be laid to rest.
(1) Co-60. EPA (US).
http://www.epa.gov/rpdweb00/radionuclides/cobalt.html
Quote:
(a) "Cobalt (including cobalt-60) is a hard, brittle, gray metal with a
bluish tint. It is solid under normal conditions and is generally similar to
iron and nickel in its properties. In particular, cobalt, like iron, can be
magnetized.
(b) "Cobalt-60 undergoes radioactive decay with the emissi
【在 d****d 的大作中提到】
: 算了吧，钴60是典型的gamma源都不知道，还beta beta的。。
:
: radioactive
: building.
|
d****d
发帖数: 2919 | 10 so ?
to
be
【在 c**i 的大作中提到】
: All of the following is for the reference of "dumand" in his various
: postings. I trust the issues may now be laid to rest.
: (1) Co-60. EPA (US).
: http://www.epa.gov/rpdweb00/radionuclides/cobalt.html
: Quote:
: (a) "Cobalt (including cobalt-60) is a hard, brittle, gray metal with a
: bluish tint. It is solid under normal conditions and is generally similar to
: iron and nickel in its properties. In particular, cobalt, like iron, can be
: magnetized.
: (b) "Cobalt-60 undergoes radioactive decay with the emissi
|
