Cac phuong phap phan tich cong cu trong hoa hoc hien dai

VIT QUII II II IINI III III III III II.0000022498

CAGPHUONG PHAP PHN TCH CNG cu

NH X U T BN I HC s PHAM

GS.TS H VIT QU

CC PHNG PHP PHN TCH CNG c

TRONG HO HC HIN I

NH XUT BN I HC s PHM

MC LCLi ni u .................................................................................................................................7

Chng 1. Khoa hc phn tch v h thng cc phng php nghin cu . 111. Khoa hc phn tch (ngnh phn tch hin i)

v phng hng pht trin.........................................................................................112. H thng cc phng php phn tch....................................................................... 12

3. Ho hc phn tch v vai tr ca ntrong ngnh Phn tch ................................................................................................. 17

Chng 2. i cng v ph v cc phng php p h ....................................... 511. Bc x in t................................................................................................................ 512. Cc phng php quang ph..................................................................................... 533. Cc phng php t hp gia phn chia v xc nh c h t................................. 67

Chng 3. Phn tch l h o ................................................................................................ 691. Cc phng php phn tch cng cu v tn hiu phn tch.................................. 692. Phn tch o quang phn t ....................................................................................... 703. Cc phng php phn tch in ho.......................................................................924. Mt s phng php phn tch, phn chia, lm giu..........................................136

Chng 4. Cc phng php o quang nguyn tvng ph U V -V IS .........................................................................................187

1. c im chung ca nhm phng php o quangnguyn t vng U V -V IS ...........................................................................................187

2. Phng php o ph pht xa nguyn t................................................................1923. Phng php o ph hp th nguyn t .............................................................. 203

4. So snh php o ph hp thu nguyn tv php o ph pht xa nguyn t ........................................................................216

5. Php o ph hunh quang nguyn t ................................................................... 2186. Cc phng php o ph nguyn t khng dng ngon la................................... 223

Chng 5. Phng php o ph hng ngoi ( IR ) .................................................2291. c im ca phng php o ph hng ngo i..................................................2292 C s l thuyt ca phng php.............................................................................2293. K thut thc nghim .................................................................................................. 2484 Cc yu t nh hng lm dich chuyn tn s c trng.................................250

5. Mt s v du c th v cc dao ng cd bn ca mt s phn t,mt s nhm trong ph IR ....................................................................................... 254

6. Phn tch nh tnh v phn tch nh lng bng cch o ph I R ..................2587. ng dng ca php o ph hng n g o a i.................................................................261

Chng 6. Phng php o ph tn x t hp (ph R a m a n ).......................... 2631. Hin tng tn xa t h p ........................................................................................... 2632 Ph k Raman.............................................................................................................. 2713. Phn tch nh tnh v nh lng trong php o ph R am an...........................2714. ng dng ca php o ph Raman......................................................................... 272

Chng 7. Phng php o ph hp th electron(ph kch thch electron vng U V -V IS ).................................................... 275

1 C s l thuyt ca phng php o ph U V -V IS ...............................................2762. K thut thc nghim.................................................................................................. 2903. ng dung ca php o ph hp th e lec tron....................................................... 295

Chng 8. Phng php o ph hunh quangv ln quang phn t ................................................................................... 309

1. C s li thuyt ca phng p h p .............................................................................3092. KT thut thc nghim.................................................................................................. 3203. Tiu chun nh gi nhy ca phn ng hunh quang..................................... 3234. ng dung ca php o ph hunh quang...............................................................324

5. Gii thiu v s pht quang ho hc.........................................................................329

Chng 9. Phng php o ph cng hng t ht nhn ................................ 3311. Phn loi cc phng php vt l ng dng trong ho ho c ..................................... 331

2. Nhng u vit ca cc phng php phn tch vt ldng trong ho h c ....................................................................................................332

3. C s l thuyt ca php o ph N M R ................................................................... 3334. KT thut thc nghim ca php o ph NM R....................................................... 3455. dich chuyn ho h c ............................................................................................ 3516. Tng tc spin - s p in ................................................................................................. 3657. ng cong tch phn tn h i u ................................................................................. 3728. Phn tch ph NMR phn gii c a o .......................................................................... 3749. Ph NMR ca cc hat nhn khc ht nhn hiro (1H )....................................... 379

10. Cc loai ph NMR 2 chiu (2D-NM R), ph NDE (1D),ph NOESY (2D), 3 chiu (3D-NM R) v 4 chiu (4D -N M R ).................. 381

11. ng dung ca php o ph N M R .........................................................................382

Chng 10. Phng php o ph cng hng spin e lectron .......................... 3831. C s l thuyt ca phng p h p ................................................................... 3832 ng dung ph E S R ............................................................................................ 395

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Chng 11. Phng php o ph khi lng........................................................ 3971. c im ca phng php.....................................................................................397

2. Nguyn tc chung ca phng php(phng php ion ho bng va chm electron)...................................................398

3. K thut thc nghim ..................................................................................................4004. Phn loi cc io n ........................................................................................................4065. C ch phn m nh .................................................................................................... 4136. Ph khi lng ca mt s hp ch t......................................................................4177. Mt s v du v phng php phn tch ph khi lng............................................. 4268. ng dng ca php o ph khi lng.................................................................. 438

Chng 12. Phng php o ph tia X (tia R nghen)........................................ 4411. c im ca phng php ..................................................................................... 4412. C s l thuyt ca cc phng php o ph tia X .............................................. 4423. Php o ph hp th tia X. S tng tc ca tia X vi vt c h t...................... 4514. Tia X nghin cu cu to mang tinh th .......................................................... 4535. Nguyn li cu to ph k Rnghen........................................................................ 4546. Phng php ph nhiu xa tia X .............................................................................4587. Phng php o ph hunh quang tia X ...............................................................4668. ng dung chung ca php o ph tia X ................................................................. 471

Chng 13. Phng php kch hot phng x .......................................................4731. Bn cht ca phng php...................................................................................... 4732. Phng php kch hot phng xa trc t i p ........................................................... 4733. Phng php kch hoat phng xa gin t i p ..........................................................4734 Hot dng phng xa t nhin...................................................................................4735. Bin i phng xa nhn t o .....................................................................................4746 Chu k bn phn hy..................................................................................................4747. Tia y .......................... ..................................................................................................... 4758 Xc inh nh tinh v inh lng.............................................................................4759 th chu n ................................................................................................................ 47610. Xc inh theo chu k bn phn h y ......................................................................47711. Phng php pha long ng v phng x a .........................................................477

12. Phn tch da theo kh nng ca cc nguyn t pht x tia p ........................478

13. Chun hoat ng phng xa ..............................................................................47914. Bc xa hoat ho bng cc ngun c nng lng ln.......................................480

15. Phn tch cc nguyn t t him bng phng phpkch hoat ntron........................................................................................................484

Chng 14. Phng php phn tch nhit(nhit khi lng, nhit vi phn, nhit qut vi phn,nhit c hc, phn tch kh thot ra )................................................... 487

1 Phn tch nhit khi lng (Thermogravimetry T G )............................................487

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2 Phn tch nhit vi phn (DTA) v php o nhit lngqut VI phn ( D S C ) ................. ...................................................................................... *"'

3 Phn tch nhit c h o c ........................................................................... ..................... 5034 Phn tch kh tch ra ................................................................................. ...................509

Chng 15. Php o ph pht x tia X .......................................................................5151 Nguyn tc ca phng php o ph pht xa tia X ............................... 5152 Thit b ............................................................................................................................5163 ng dung........................................................................................................................ 5164 Cc nguyn t c ............................................................................................................ 5165 Ki thut thc nghim .................................................................................................... 519

Chng 16. Php o ph plasm a cm ng t h p ............................................... 5231. Nguyn tc ca phng phap................................................................................... 5232 Plasma cm ng t hp..............................................................................................5233. Php o ph plasma cm ng t hp - ph khi lng..................................... 5234 Cc nguyn t c ............................................................................................................ 5245. Thit b| plasma cm ng t hp................................................................................5256. Php o ph plasma cm ng t hp - khi p h ................................................ 5277 ng dung........................................................................................................................ 529

Chng 17. Cc phng php t hp gia tch - xc nh hp c h t..........5311 Gii php t hp........................................................................................................... 5312 Chin lc phn tch t h p.......................................................................................5323 Cch gii quyt vn ............................................................................................... 5324. Cc u vit ca cc phng php (k thut) t h p.............................................5335 Bin php t h p.......................................................................................................... 533

6 Gii quyt vn ................................................................................. 5347. Cc u th ......................................................................................................................535

8 Sc k kh - ph hng ngoai (Gc - IR /S ).................................................... 5369 Sc k lng - ph khi lng (Lc - MS).......................................... 54210. Php o ph plasma cm ng t hp - ph khi lng (ICP - MS) 54511 Cc phng php t hp gia chit v cc phng php xc inh 546

Chng 18. Kt hp cc phng php ph nhn bitv xc nh cu trc phn t ..................................................................5 5 5

1. Nhn bit v xc inh cu true phn t tvic kt hp cc phng php ph............................................. 5 5 5

2 Mt s nguyn tc ca phng php gii ph............................... ec;53 PQ dung.................................................................................................. 55 '

Ti liu tham kh o ................................................................................................................55C

LI NI U

Cc phng php phn tch cng c bao gm cc phng php phn tch l - ho v cc phng php phn tch vt l ng dng trong Ho hc hin i. Trong cc phng php phn tch cng c, Ton hc, Tin hc ng vai tr cc k quan trng. Chng gip cho vic x l thng k kt qu, m hnh ho, k hoch ho, ti u ho thc nghim, tnh kt qu, x l th, tnh sai s phn tch...

Cc phng php phn tch cng c l gio trnh phc v cho cc h o to C nhn (h chnh quy, ti nng, ti chc, chuyn tu), Thc s, Tin s Ho hc trong nhiu trng i hc v Cao ng ca nhiu ngnh o to khc nhau.

Gio trnh ny c a vo chng trnh o to Thc s v Tin s, C nhn cc h t nm 1991. Nh xut bn i hc Quc gia H Ni xut bn ln u nm 1998, gio trnh phc v kp thi vic o to cc h o to ni trn.

T nm 1991 n nay, trong lnh vc cc phng php phn tch cng c xut hin nhiu phng php, cc k thut phn tch hin i, c hiu qu cao trong phn tch nh tnh, nh lng, cu trc, v d k thut bin i Fourier (Fourier Transformation = FT) trong cc phng php FT - IR/S; FT - Raman/S; FT - MS; FT - NMR/S, cc th h ph k NMR t 500MHz n 800MHz, a xung , a chiu, kh tng tc, 1, 2, 3, 4 chiu (1D - NMR, 2D - NMR, 3D - NMR, 4D - NM R,...) cho php tng tn hiu o, gim tn hiu nhiu, gim sai s, tng phn

gii, nhy, chn lc, chnh xc; hu nh trong nhiu trng hp khng cn phi tch trc cc cu t cn tr trong mu phn tch, tit kim c cng sc, gim thi gian phn tch... m t hiu qu phn tch cao.

Xut hin nhiu k thut, nhiu phng php t hp (combined technigues, methods) gia cc phng php tch v phng php xc nh hm lng cht nh: sc k kh (lng) - ph khi lng, ph hng ngoi bin i Fourier (Gc - FT/MS; Gc - FT/IR; Lc - FT/MS; Lc - FT/IR), phng php tim mu vo trong dng chy (FIA = Flow Injection Analysis), chit - trc quang (hunh quang, cc ph), o hot phng x, chun , ph plasma cm ng t hp - p h khi lng (ICP - MS = Inductively Coupled plasma - Mass Spectrometry)... cho php va tch c cc cu phn t hn hp mu va xc nh c hm lng ca chng. Ngy nay, trong Ho hc hin i, vic xc nh hm lng ln v trung bnh l vn c gii quyt, cc phng php phn tch cng c cho php xc nh c hm lng vt, siu vt (v d, IC P -M S , AAS, AFS...).

Gio trnh Cc phng php phn tch cng c tro n g Ho hc h in i gm 18 chng, cp mt cch ton din cc phng php phn tch l - ho (phn tch quang hc, phn tch in ho. phn tch phn t, phn tch nguyn t...), cc phng php phn tch vt l (cc phng php phn tch quang ph , ph hp th electron vng U V-V IS ph hunh quang, ln quang phn t, ph hp th. pht xa. hunh quang, tia X nguyn t, ph plasma nguyn t, ph huynh quang, ph Raman, ph khi lng, ph cng hng t ht nhn (NMR. PMR). ph hp th, nhiu x, hunh quang tia X), cc phng php tch, phn chia, lm giu.

Cc phng php phn tch sc k: sc k khi (rn, lng), sc ki lng (rn, lng), sc k i bn mng, sc k giy, sc k gel (sc k ry phn t) sc ki trao i ion, sc ki in di, sc ki mao qun...

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Cc phng php chit bng dung mi hu c, chit pha rn..

Cc phng php tch bng in ho, kt ta, chng ct, thng hoa..

Qua 28 nm o to h Sau i hc trc y v h Cao hc (hin nay), tc gi thy cn phi bin son gio trnh ny mc hin i, cp nht c th c nhm phc v cc h o to C nhn (c bit h C nhn cht lng cao), h o to Thc s v Tin s Ho hc vi cht lng ngy cng tng.

Tc gi mong mun nhn c s gp , b sung ca bn c, ng nghip ln xut bn sau cht lng gio trnh cng tt hn, phc v c hiu qu hn s nghip o to, nghin cu khoa hc, bi dng cn b...

Tc gi xin chn thnh cm n.

TC GI

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Chng 1KHOA HC PHN TCH V H THNG

CC PHNG PHP NGHIN cu

1. Khoa hc phn tch (ngnh phn tch hin i) v phng hng pht trin

Trong cng tc nghin cu khoa hc. ging dy t bc i hc, trn i hc, ngnh Ho hc phi c trang b cc phng php phn tch c hiu qu cao nhm phc v cho cc mc ch nh: nhn bit cht, xc nh hm lng cht, c bit hm lng vt. siu vt (c ppm. c ppb...). xc nh cu trc phn t. tinh ch. iu ch cc hp cht siu tinh khit dng trong k thut cao nh bn dn. siu bn dn. cng nh tinh vi...

Ngy nay. trong Ho hc hin i v ang s dng nhiu phng php phn tch ho hc, phn tch l ho, phn tch vt l (thng i l phng php phn tch cng c), s dng ton hc. tin hc x l s liu thc nghim (ton thng k), ti u ho thc nghim, k hoch ho. m hnh ho thc nghim, nghin cu co' ch phn ng, xc nh cc tham s' nh lng cc hp cht to thnh...

Nh vy. do s kt hp hu c gia Ho hc. Vt l. Ton hc. mt s khoa hc khc nh Sinh hc. Dc hc. Y hc. a l. a cht. Mi trng. Kho c hc v.v... ra i Khoa hc phn tch, tc ra i ngnh Phn tch hin i phc v c hiu qu cho nghin cu khoa hc. ging dy Ho hc. khai thc, s dng ti nguyn... phc v tt cho cng cuc hin i ho. cng nghip ho t nc.

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