VI. PHUdNC PHAP PHAN TicH el/e PH6: [6,7,8,16]
6.Cae nguyen nhan gay sai sil trong phu'o't1g phap phan tieh kleh hO<,tt :
6.1.Hi~1lling chin:
Khi ehi~u bia biing notron nhi~t, m9t s6 h<.Jpeh~t co kha nangh~pthu notron nhi~t m<,tnh (nhu Cd, B, Ag), gay anh hti6ngd~n k~tqua phan tieh. K~tqua la thong lti<.Jng dong notron giam khi notroq di qua b~ day eua mftu. Do s\f hfip th\l notron nhi~teua cae t<,tpeh~tnoi tren nen hO<;lLd9 phong x<,t saukhiehi~uthfip han so vdikhi
khong cohi~uung.
Trong do:
<Do :Thong hlqng dong ndtron6b~ m~t m~u
<Dx :Thong Il1qng dong ndtron tq.i di@m eachb~ m~tm(\t khoang x (cm). cr :Ti~t di~nh.ip thl.} ndtronOOi~t(bar hay cm2)
L : s6 nguyen tVchi~utren bia.
Ngl1(ji ta loq.i truhi~u ting tljch~n b~ng cachchi~u m~u co kich thl1dc 000, b~ day 000,m~u 6 d,;mg long hay x6p.
6.2. Cac ph3n ling cJ!nh tranhvaph31l ung thtlcip :
Khiphan tich kich hoq.t neutronr0i~tben cq.OO cac phan ting chiOO (n, y) co th@ xay ra cac phan ting phI.} cq.OO traOO (n, p); (n,a)vi khOng phai hic nao clingnhi~thoa dl1qc hoan toan cac ndtron.
Phan ting cq.OO trq.OO xu.ithi~nkhi trongm~u co cac nguyen t6 co s6hi~uZ+I, Z+2 cung vdi nguyen t6 phan tich co s6 hi~u Z. K~tqua la s6 hq.t OOan cua d6ng vi phong xq. tang len bao g6mph~ncua phan ting hq.t OOan cd ban vaph~ncua phan ting hq.t OOan cq.OO traOO, phan ung thti dp dong gop. Sai s6 phan tich se r.it Idnn~uta phan tich m(\t Il1qng be cac nguyen t6.
6.3.NhU'ng ult khuyit cUa phu'Obg phap :
Phl1dng phap kich hoq.t ndtron coOOi~uuu di@m so vdi cac phudng phap khac, d~c bi~tno la m(\t trong OOilng phudng phap co d(\ OOq.y cao oo.it trong hoa phan tich. Ngoai ra phl1dng phap con co tiOOd~c hi~u cao vi d6ng vi phong xq. duqc phan tich khong OOilng theo dq.ng tach hoa hQC rna con theo chukyban ra va nang Il1qng cua buc xq..
B~ng cach sV dl.}ng phl1dng phap phan tich kich hoq.t ndtron co th@ xac diOO dl1qc OOilng Il1qng 000 cua cac nguyen t6 khac OOau trong nudc, trong d.it...
Nhuqc di@m cd ban ia khong phai t.itelicac nguyen t6d~uco th@ xac diOO duqc b~ngphl1dng phap nay. Nguyen t6 phong xq. duqc tq.o thaOO saukhikich hoq.t dn pMi co chukyban ra thich hqp d@ co th@ti~nhaOO m(\t cachthu~n Iqivi~ctach hoa va do d(\ phong xq. cua nguyen t6 dn tach.
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