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002603 TRUONG DAI HOC Y HA NOI m m • BO MON VAT LY (SACH DUNG C H O SINH VIEN HE BAC Si D A KHOA) NHA XUAT BAN Y HOC TRUONG OAI HOC Y HA NOI ■ ■ ■ BO MON Y VAT LY VAT LY LY SINH Y HOC (SACH DUNG CHO SINH VlfiN HE BAC SI DA KHOA) ^ \o U r,; !>■' -\K V IE PKU t h o T H U V i l N s e : fe * r NHA XUAT BAN Y HOC HA NOI - 2006 i& X Dong chu bien: PGS TS Nguyen VSn Thien PGS TSKH Phan Sy An Tham gia bien soan: PGS TSKH Phan Sy An PGS TS Nguyen V9n Thien TS Phan Thi Le Minh ThS Doan Thi Giang Hi/dng CN Nguyen Thanh Thuy ThS Tran Thi Ngoc Hoa ThS Ngo Dung Tuan Thu ky bien soan: ThS Doan Thj Giang Huong LOI NOI DAU Vat ly hoc la mot nganh khoa hoc tU nhien nghien ciiu nhutng dang van dong cd ban nhat cua vat chat roi tim cach ilng dung chung phuc vu ddi song Trong qua trinh phat trien, cac nganh khoa hoc dan xen vao lam sinh cac nganh khoa hoc mcfi, thi du nhU ly sinh, hoa sinh Chiidng trinh Vat ly - Ly sinh difdc day tai trUdng Dai hoc Y Ha Noi tii nam 1956 M uc tieu cua chUdng trinh la giup sinh vien: - Hieu dung cac dinh luat vat ly cd ban co nhieu ling dung sau nghien ciiu y hoc va bao ve sufc khoe cong dong - Phan tich dUdc cac qua trinh, hien tUdng vat ly cd ban xay trdng cd the song - Trinh bay dUdc nguyen ly cua cac ting dung ky thuat vat ly chinh ch&n doan va dieu tri - Phan tich dUdc cac tac dung chinh cua cac yeu to" vat ly len cd the song phuc vu muc dich bao ve moi trUdng va cd the Do do"i tUdng phuc vu chinh la cac sinh vien nam thii nhat trUdng Dai hoc Y nen giao trinh dUdc viet tUdng do"i ddn gian, khong dung nhieu cong cu toan hoc, chi yeu cau ngiidi hoc co kien thilc thong trung hoc ve vat ly va sinh hoc Giao trinh Vat ly - Ly sinh y hoc dUdc viet v6i thdi lildng mon hoc la 75 tiet theo quy dinh khung chUdng trinh cua Bo Y te va Bo Giao due Dad tao 1.1 PhUdng trinh cd ban cua thuyet dong hoc phan tti va cac he qua 55 1.2 Stic cang mat ngoai va hien tUdng mao d&n 57 1.3 Cac hien tUdng van chuyen vat chat cd the 62 1.4 Van chuyen vat chat qua mang te bao 72 Chuyen dong cua chat long va sii van chuyen mau cd the 81 2.1 Cac phan tti va ion cd the 81 2.2 Cac dinh luat ve sU van chuyen cua chat long 82 2.3 Su van chuyen mau 86 Khi va sU van chuyen cd the ngUdi 92 3.1 Hoat dong ho hap 92 3.2 Cac quy luat khuech tan 94 3.3 Su van chuyen cd the 96 3.4 Nhting yeu to' anh hUdng tdi sU trao doi cd the ngUdi 96 Chuyen dong cd hoc tren cd the song 97 4.1 Dai cUdng ve chuyen dong cd hoc 97 4.2 Chuyen dong cd hoc tren cd the song B Dao dong va song Dao dong cd hoc 103 110 110 1.1 Dao dong dieu hoa 111 1.2 Dao dong tat dan 113 1.3 Dao dong cUdng btic va hien tUdng c6ng hUdng 114 1.4 Tong hdp va phan tich dao dong 116 Song cd hoc moi trUdng dan hoi 118 2.1 Moi trUdng dan hoi 118 2.2 Song cd hoc 118 Dao dong va song dien tti 125 3.1 Mach dao dong dien tti Dinh nghia dao dong dien tti 125 3.2 Dao dong dien tti dieu hoa (khong tat) 126 3.3 Su tUdng tU gitia dao dong dien tti khong t i t va dao dong dieu hoa cua lac ddn 128 3.4 Dao dong dien tti tat dan 129 3.5 Cach tao song dien tti 131 Bien doi, khuech dai va ghi giti tin hieu 139 4.1 Bien doi tin hieu khong dien dien 139 4.2 Nguyen ly khuech dai tin hieu dien 141 4.3 Ghi va bao quan tin hieu dien 145 Am va sieu am 148 5.1 Ban chat vat ly cua am va sieu am 148 5.2 Nguon phat am 150 5.3 Cac dac trUng cua cam giac am 152 5.4 So lUdc ve qua trinh nghe 157 5.5 Cd sd vat ly cua phUdng phap am ch&n doan 160 5.6 Sd lUdc ve iing dung sieu am nganh y 162 Song va sU song 167 6.1 Sd lUdc ve tac dong cua song den sU song Tac dong cua song den sU song co loi hay co hai? 167 6.2 Sd lUdc ve nhip sinh hoc 168 Bai D ien va svf song Dien the sinh vat d te bao song 170 171 1.1 Dien the nghi 171 1.2 Dien the hoat dong 175 1.3 SU lan truyen dien the hoat dong 179 Dien the hoat dong cua to chiic song 181 2.1 Dien the hoat dong cua tim 181 2.2 Cac dien the hoat dong khac dUdc dung nhieu chan doan 187 Tac dung cua dong dien len cd the 189 3.1 Phan iing cua cd va than kinh doi vdi klch thich dien 189 3.2 Cac thong so' dien cua cd the 192 3.3 Nguv hiem dien Cac bien phap an toan dien 194 3.4 Tac dung tich cUc cua dong dien len cd the va iing dung y khoa 198 Bai Cac dinh luat quang hinh cd ban - m at Cac dinh luat cd ban cua quang hinh hoc va mot so" dung cu quang hinh 204 204 1.1 Cac dinh luat cd ban cua quang hinh hoc 204 1.2 Mot so dung cu quang hinh 207 Mat va dung cu bo trd 2.1 Quang hinh hoc cua mat 223 223 2.2 Kha nang phan ly cua m&t 226 Cac tat quang hinh cua m&t va dung cu bo trd 229 Bai Ban chat cua anh sang Thuyet song dien tti ve ban chat cua anh sang 235 235 1.1 Thuyet song dien tti ve ban chat cua anh sang 235 1.2 Hien tUOng giao thoa anh sang 238 1.3 Hien tUdng nhieu xa anh sang 244 1.4 Hien tUdng phan cUc anh sang 249 Thuyet lifdng tti ve ban chat cua anh sang 2.1 Hieu ting quang cy.en ngoai 250 250 2.2 Thuyet liidng anh sang cua Einstein va sii giai thich hien tUdng quang dien 252 Cac mtic nang liidng cua tap hdp dien tti 3.1 Mtic nang ltfdng cua tap hdp dien tti 257 3.2 Hap thu anh sang va phat sang 258 Laser 262 4.1 Khai niem ve btic xa cam ting 262 4.2 Laser va may phat tia laser 263 4.3 Sd ltfdc ve ti'nh chat cua chtim tia laser 265 4.4 n g dung cua laser Bai Tac dung cua anh sang len cof the song Dai cUdng ve tac dung cua anh sang len cd the song 265 267 267 1.1 Cac giai doan chinh cua mot qua trinh quang sinh 267 1.2 Phan loai cac qua trinh quang sinh 268 1.3 Mot so" dac diem cua qua trinh quang sinh 268 Mot so qua trinh quang sinh 257 272 2.1 Quang hdp 272 2 Sinh tong hdp sac to" va vitamin 274 2.3 Tac dung quang dong lUc (TDQDL) 275 2.4 Tac dung cua tia tti ngoai len cac he thong song 278 2.5 Thong tin thu cam anh sang 280 Bai Btic xa ion hoa va cd the song Khai niem va nguon goc cua btic xa ion hoa 292 292 1.1 Cau tao hat nhan nguyen tti 292 1.2 Hien tUdng phong xa 293 1.3 Dinh luat phan phong xa 298 TUdng tac cua btic xa ion hoa vdi vat chat 300 2.1 Ttidng tac cua hat vi mo tich dien vdi vat chat 300 2.2 TUdng tac cua photon nang lUdng cao (tia y va tia X) vdi vat chat 303 2.3 Ttidng tac cua neutron vdi vat chat 306 Su hap thu nang lUdng btic xa - Lieu lUdng btic xa 308 3.1 Su hap thu nang lUdng btic xa Su suy giam cUdng btic xa 308 3.2 Lieu ltfdng btic xa 310 3.3 Nguyen ly va cac thiet bi ghi btic xa ion hoa 312 Tac dung cua btic xa ion hoa len vat chat song 317 4.1 Cd che tac dung 317 4.2 Cac ton thUdng d cd the sinh vat dudi tac dung cua btic xa ion hoa 321 4.3 Cac yeu to" anh hUdng den hieu ting sinh hoc cua btic xa ion hoa 327 4.4 Cac nguyen tac ve kiem soat va an toan btic xa 330 Bai 10 M ot so ting dung bien cua V at ly ky thuat tron g nganh Y PhUdng phap hien vi 337 337 1.1 Nguyen ly phong dai anh vat Kinh lup 337 1.2 Kinh hien vi quang hoc trUdng sang (KHVQHTS) 338 1.3 Do phong dai Kha nang phan ly 340 1.4 Cac loai kinh hien vi khac 343 1.5 Cach kich thudc cac vat nho bang kinh hien vi 347 PhUdng phap quang hap thu phan tti 349 2.1 Su hap thu anh sang cua moi trUdng vat chat 349 2 Ung dung cua quang hap thu phan tti 352 PhUdng phap tao anh bang tia X va cong hUdng tti hat nhan 357 3.1 Thiet bi tao tia X 357 3.3 Chup hinh bang cong hUdng tti hat nhan 366 PhUdng phap phong xa 376 4.1 PhUdng phap danh dau phong xa 376 4.2 PhUdng phap dting nguon chieu xa 379 diidc giiia hai diem cua cd the goi la chuyen dao dien tim (hoac dao trinh) Tam giac Eithoven se cho ba chuyen dao lan ltidt la: Chuyen dao D[ ghi hieu dien the giiia tay trai va tay phai - Chuyen dao Dn ghi hieu dien the giiia tay phai va chan trai - Chuyen dao Dm ghi hieu dien the' giiia tay tra i va chan trai Mgoai co cac chuyen dao khac niia Ngtidi ta can den cac chuyen dao khac de xac dinh ttidng do'i hinh chieu cua vec td stic dien dong tim len mat trtidc cd the, mot dti lieu cung dtidc dung chan doan 2.1.4 May tao nhip tim (pacemaker) Vi nhieu qua trin h sinh ly dtidc kich hoat bdi cac xung dien dtidc tao cd the bang cd che sinh hoc nen da xuat hien y ttidng rang, co the phat dong dtidc cac qua trinh bdi cac xung dien nhan tao ttidng dtidng May tao nhip tim la mot th i du khong xa la ve sti cong cua y ttidng Nut SA la mot “ may tao nhip tim ” thien nhien, nhien no khong phat huy chtic nang hoac he dan truyen xung dien den cac tam that bi "ket” , hoat dong nhip nhang cua tim bi pha vd Nguyen nhan bien nhat van la cac xung bi “ket” tren dtidng dan truyen Khi tam nhi van co bop tuan theo nhip cua nut SA, nhting tam that thi co bop theo nhip doc lap cua nut AV, nhip cham hdn, khoang 30 - 40 nhip/phut May tao nhip tim, dtidc nuoi bdi pin, tao cac xung dien kich thich theo mot nhip da dtidc dinh trtidc Bien dien hinh cua xung dien -10 mV, thdi gian keo dai xung khoang vai mi li giay, tan so' xung khoang 60 -70 xung/phut Cac dien ctic dtidc gan vdi cd tim Cac may tao nhip tim tinh vi lam viec che “trtic chien”(standby), co nghia la no chi hoat dong nhip dap tim xuong tha'p hdn mtic nao Tuy goi la “ may” nhting no rat nho va dtidc ca'y dtidi da d vung bung hoac ngtic, cac day dan se no'i no vdi tim Phan “hop dien tti” co the d l dang lam nho va co tuoi tho cao Van de chinh la nguon cung cap nang ltidng rat can phai nuoi dtidc may that lau Mot so' loai pin dac biet co the nuoi may 10 -20 nam Neu pin het, se can den mot tieu phau thuat Phau thuat ldn la dat cac dien ctic va day dan den tim Mot nhting htidng giai quyet van de nguon nuoi la, nang ltidng cho may se dtidc cung cap bdi chinh cac hoat dong cd hoc cd the Con co nhting htidng di khac day htia hen tat ca deu nham lam cho benh nhan dtidc dat may tao nhip tim hoan toan khong cam giac co mot thiet bi dien tii ngtidi ho Ban chat dien cua nhieu cd che dieu khien cd the md nhting kha nang to ldn viec ting dung cac xung dien nhan tao de kich thich hay dieu hoa cac qua trin h sinh ly Ngay khoa hoc da cong viec che tao cac dung cu thay the cho nhting ngtidi tan tat dtidc dieu khien bang cac y nghi cua ho 186 2.2 Cac dien the hoat dong khac difdc dung nhieu chan doan 2.2.1 Ghi dien nao va dien nao dd Nao ngudi co mot cau tao phiic tap, gom khoang 1010 te bao than kinh (ndron) Moi te' bao nao giong nhu mot nguon dien ty hon ma dien the hoat dong luon luon bien doi Cac te bao nao lien he chat che vdi nen moi bien doi ve dien cua mot te bao lai keo theo nhutng bien doi ve dien d cac te bao khac Ket qua la nhieu te bao nao co the hdp nhat dong dien hoat dong cua chung trang thai dong bo (synchronized) Qua trin h tao nen cac song dien nao, cac song co kha nang truyen qua xUdng so va da dau Tinh chat cua dien nao do nhieu thong so' quyet dinh, nhien tren thuc te chu yeu ngUdi ta dUa vao tan so' cua chung Co nhieu tac gia phan loai theo quan niem va kinh nghiem cua minh, nhUng nhin chung khong co sai lech nhieu lam, du6i day la sU phan chia bien cac nhom song Song delta (8): 0,5 -j- 3Hz Sdng theta (9) : -s- 7Hz Song alpha (a): 8-s- 13Hz Sdng beta (P): 14 -5- 30Hz Song gamma (y): 30 -r 50Hz Song dien nao la nhiing dao dong co tan so', bien va hinh dang khac (hinh 5.11) - Song delta thudng xuat hien d dien nao trUdng hdp dang ngu sau hay benh ly nhu hon me, song thudng ghi dUdc d phan sau cua nao - Song theta thudng gap tren dien nao cua tre em, nhung d liia tuoi ldn hdn 10 th i bien va so' lUdng cac song theta giam di nhieu ngUdi khoe manh khong phai luc nao cung ghi dUdc song theta Bien cua song theta vao khoang 20 -r 50)uV Tren dien nao co the nhin tha'y cac song theta rieng le hoac tap hdp tiing cum - Song alpha xuat hien d da so' trUdng hdp ngUdi ldn khoe manh dieu kien thu gian ve giac quan va tinh than Bien co the khoang 20 + 100|j.V - Sdng beta ghi dUdc tren dien nao cua da so' ngUdi, nhung tren ngUdi khoe manh chi chiem mot ti le rat nho Tuy theo tiing tac gia, bien song beta d khoang h- 5pV Sdng beta cd the xem la dac trUng cho phan trudc cua nao (vung tran va vung trung tam), nhUng tren mot so' ngUdi song beta dUdc the hien nhieu d vung thai dudng K hi ghi dien nao ngUdi ta cho do'i tUdng doi mot cai mu dac biet co cac dien cUc nho bang kim loai cd the tiep xue vdi da dau qua mot loai sap d§n dien Tuy theo vi tri dat dien cUc ma ta cd cac chuyen dao khac 187 - Chuyen dao don cUc: Trong trUdng hop mot dien ciic dUdc dat vung co hoat dong dien nao, goi la dien cUc hoat dong, dien cUc dat xa ndi phat dong dien nao, goi la dien cUc trung hoa (thudng dat dai tai, hoac d mui) - Chuyen dao ludng cUc: Doi vdi chuyen dao ludng cUc ca hai dien cUc deu dUdc dat tren vung hoat dong cua nao Ca hai dien cUc deu dUdc goi la dien cUc hoat dong Dien the thu dUdc chuyen dao ludng cUc la tong dai so dien the cua hai dien cUc Alpha He thong phan bo dien ciic quoc te: De kh^c phuc tinh trang sai lech cac ket qua nghien ciiu thu dUdc cua cac tac gia va de giup cho viec theo doi dien bien benh tat qua dien nao tren mot ngUdi benh dUdc dong nhat, hoi nhUng ngUdi nghien ciiu dien nao quoc te da dUa he tho'ng phan bo dien cUc dat tren dau theo mot ti le khoang cach va mot trin h tu nhat dinh phu hdp vdi vi tr i giai phau cua nhiing phan khac bo nao Dien nao (EEG: electro encephalogram) rat cd gia tri chan doan dong kinh, khoi u, mot so dang nghien ma va cac benh khac lien quan den nao Beta D elta Theta Hinh 5.11 2.2.2 Ghi dien co Chung ta da biet ddn vi chiic nang cua bo may than kinh van dong dUdc goi la ddn vi van dong Thanh phan chu yeu la te bao than kinh van dong va mot nhom sdi cd ma no dieu khien trang thai nghi ngdi, dien the mang cua sdi cd ngudi trung binh khoang 80mV Khi cd kich thich, xung dong dUdc truyen tu day than kinh den sdi cd sdng khu cUc cua mang dUdc truyen theo sdi cd va chung ta ghi dUdc dien cd dudi dang dien the hoat dong Dang cua dien the hoat dong phu thuoc vao cau true cua ddn vi van dong, loai dien cUc va vi tr i cua dien cUc (xuyen vao hay tiep xue be mat) ngudi khoe manh, dung dien cUc kim xuyen vao cd cd the dan dUdc dien the hoat dong cua mot ddn vi van dong cd co chu dong No la ket qua cong dien the hoat dong cua nhung sdi cd gan dien cuc kim thuoc ddn vi van dong dd vi 188 nhting s d i cd d gan cung dtidc kich thich bang chinh xung dong tif day than kinh den Dien the hoat dong cua ddn vi van dong la mot chudi cac xung giong ve hinh dang va bien (hinh 5.12) 50 ^ ' ICO f l i t Hinh 5.12 Dien the dong cua ddn vi van dong (cd bap tay) Dien cUc dong tam Dien ci/c ludng cUc Trong thuc te cd la mot cd quan tho'ng nhat, cac ddn vi van dong lam viec dtidi sti dieu khien cua than kinh Sti phoi hdp va lam viec cong dong cua cac don vi van dong dtidc the hien qua Hinh 5.13 Sir chuyen tCr dien the dong cua cac ddn vi van dong rieng biet sang dien cd dien cd giao thoa Khi dung giao thao dien ctic kim de nghien cUu dien cd do, ta thay cd co yeu chi mot vai ddn vi van dong lam viec, dien the hoat dong cua no thUa thdt; cd co manh tren dien cd thay hinh anh day dac cua cac dien the hoat dong chting to cd nhieu ddn vi van dong di vao hoat dong Ket qua cho ta dien cd giao thoa, luc chung ta khong the phan biet dtidc dien the hoat dong cua tting ddn vi van dong (hinh 5.13) Dien cd (EMG: electromyogram) dtidc dung chan doan nhting roi loan than kinh-cd va de theo d5i sti phuc hoi day than kinh sau ton thtidng cd TAC DUNG CUA DONG DIEN LEN CO THE 3.1 Phan umg cua cd va than kinh doi vdi kich thich dien Chung ta cd the dung cac yeu to' cd, nhiet, dien, hoa de kich thich cd va than kinh Tuy nhien cac th i nghiem khao sat tinh dap ting cac kich thich cua te bao va mo ngtidi ta thtidng dung ddng dien lam tac nhan kich thich cac tiu diem rd ret cua no Thti nhat, te bao cd va than kinh nhay cam nhat do'i vdi cac kich thich dien Thti hai, ctidng va thdi gian tac dong cua kich thich dien la cac dai ltidng dtidc va de dieu tiet Kich thich dien thtidng dung la xung vuong 3.1.1 Dinh luat tat ca hoac khong Thtic nghiem xac nhan r£ng vdi nhting kich thich dien cd thdi gian keo dai nhat dinh, neu ctidng nho, phan ting cua cd va than kinh chi xuat hien tai chd 189 dat dien ctic kich thich, bieu hien bang mot xung the hieu co dac tinh la bien dp tang d£n theo ctidng cua kich thich (hinh 5.14) Do la phan ting tai cho Neu kich thich co ctidng du ldn, nghia la vtidt qua mot gidi han xac dinh goi 16 ngtidng kich thich thi no tao dtidc tren te bao cd hay than kinh trang thai hting phan bieu hien bang mot dien the hoat dong, sau lan di doc theo te bao va c6 bien khong doi suot qua trin h lan truyen (hinh 5.14) Kich thich tren ngtidng du ldn den dau cung chi tao xung dien dong giong (xem dac diem dien the hoat dong) /N NgUdng kich thich £ Hinh 5.14 Su dap ung cua dien the mang vdi ci/dng kich thich dien 3.1.2 Mdi lien quan giua s i/x u a t hien phan va cac thong so cua kich thich De xac dinh mtic de hting phan cua te bao cd hay than kinh, nha sinh ly hoc Phap L.Lapicque de xuat ghi lai hai thong so' cua kich thich dien: ctidng kich thich va thdi gian keo dai kich thich Mot kich thich bat ki vdi hai thong so tren dtidc cho ting vdi mot diem mat phang (I, t) Tren thi d hinh ve 5.15 bieu d iln dtidng cong ngtidng dac trting cua mo hay te bao nao Dtidng cong ngan mat phang (I, t) hai mien: mien tren ngtidng va mien dtidi ngtidng Moi kich thich thuoc mien dtidi ngtidng khong the gay nen hting phan va moi kich thich thuoc mien tren ngtidng se gay dtidc hting phan Qua dtidng cong dang hyperbol co the thay rang, de cho kich thich gay dtidc hting pha'n tren te bao hoac mo, ctidng kich thich cang nho th i thdi gian kich thich doi hoi cang dai va ngtidc lai 190 Hinh 5.15 Tti thi 5.15 Chung ta co khai niem ve cac dai ltidng sau: - Ngtidng thdi gian C Do la khoang thdi gian ngan nhat ma xung dien kich thich phai keo dai de co the gay nen hting phan tren te bao O dong vat co xtidng song, gia tri C cua te bao than kinh vao khoang fas Ta thay rang neu thdi gian keo dai cua xung dien ngan hdn C th i du xung dien co ctidng ldn den dau cung khong co kha nang gay nen trang thai hting phan cua cd hay than kinh - Ngtidng kich thich hay reobazd (Rheobase) ky hieu la b Do la ctidng nho nhat ma xung kich thich phai dat dtidc de gay nen trang thai hting phan tren cd hay than kinh Theo hinh 5.15 ta thay t-» co thi I —> b vi vay co the xac dinh b theo thi Ta thay rang neu ctidng cua xung kich thich nho hdn b th i du co keo dai bao lau xung dien cung khong the gay hting phan tren cd hay than kinh Reobazd cang nho, te bao hay mo cang de hting phan - Thdi tr i hay cro-nac-xi (Chronaxi) Do la khoang thdi gian ngan nhat ma mot xung dien co ctidng gap hai lan ngtidng kich thich (2b) can phai keo dai de gay nen dtidc hting phan tren cd hay than kinh Cro-nac-xi cang ngan, hting phan tren doi ttidng xuat hien cang nhanh Ngtidi ta thdi tri bang thdi tri ke (chronaximeter) Viec xac dinh thdi tri bien thtic nghiem va lam sang, th i du thdi tri de xac dinh mtic ton thtidng cua day than kinh van dong Hdp cac kich thich: Hai kich thich dtidi ngtidng co the gay nen hting phan tren te bao (hien ttio'ng cong tac dung hai kich thich dudi ngtidng) neu nhti: 191 - Hai kich thich dtidi ngtidng cung tac dung vao mot vi tr i cua te bao cach khoang thdi gian du ngan - Hai kich thich dtidi ngtidng dong thdi tac dung vao hai vi tr i du gan cua te bao Cac thong so dien cua cd the Viec nghien ctiu cac thong so' dien cua te bao va mo nham hai muc dich chinh Thti nhat la tim hieu mot so' dac tinh vat ly cua vat chat song Thti hai la nghien ctiu sti bien doi cua cac thong so' dien lien quan vdi trang thai chtic nang cua he, vi nhting dieu kien nhat dinh cua cd the cac thong so thtidng co gia tr i ttidng do'i co' dinh 3.2.1 Do dan dien cua cac mo doi vdi ddng dien khong doi Thong so dien cd ban cua mot doi ttidng la dan dien L va dien trd R cua no Gitia chung co moi lien he ddn gian sau: i= I R Thong thtidng R dtidc xac dinh qua cong thtic: R=P s do: p la dien trd sua't; Cla chieu dai cua do'i ttidng va S la be mat tiet dien ngang cua do'i ttidng Viec xac dinh gia tr i dien trd sua't cua cac he tho'ng song la mot van de het stic kho khan va phtic tap Trtidc het, cac do'i ttidng la mot he tho'ng khong dong nhat, da pha Thti hai la tren be mat tting te bao bao gid cung co mot ldp chat long vdi dan dien rat cao va binh thtidng khong the tach ldp vo dd dtidc, vi neu tach ldp vd te bao se chet Khi xac dinh d in dien cua mo hoac cd the da bao ta cung gap phai nhting kho khan tren Trong trtidng hdp nay, dong dien chu yeu di qua vung gian bao cd dan dien kha ldn, vi tai dd cd nhieu loai ion vd cd cd nong cao Mat khac khoang gian bao khong phai la mot dai ltidng co' dinh ma thay doi theo trang thai cua cac te bao, chang han nhti te bao bi trtidng hoac bi teo Hdn ntia nong cac ion gian bao cung thay doi Tuy vay ngtidi ta cung xac dinh dtidc ttidng do'i d in dien cua cac mo khac cd the - Cac mo md va md cd cd dien trd sua't nhd nhat, p =10 Qm - Da kho va xtidng cd dien trd sua't ldn nhat, p =106Qm - Cac chat dich cd the nhti song, mau dan dien rat tot p =lQm Do dan dien cua cac md va cac cd quan phu thuoc vao tinh trang hoat dong cua chung, dd cd the dtidc dung chan doan Thi du mot to chtic bi viem cac te bao trtidng len khoang gian bao hep lai va dan dien giam xuong 192 3.2.2 Tong tra (impedance) cua te bao va mo Trong cd the song ton tai vo so" cac mang sinh vat, cac mang co tinh chat tiidng tii nhii cac tu dien, g in nha khong cho dong mot chieu di qua nhiing cho dong xoay chieu di qua Chinh vi vay dien trd cua cac mo do"i vdi ddng mot chieu r&"t ldn Con doi vdi dong xoay chieu thi ngoai p h ln dien trd th u ln cua mo, he dien dung tren cung gop phan vao sii dan dien N hii vay dien trd cua te bao va mo la tong trd (impedance) cua dien trd thuan va dung khang cua chung Sii co mat cua phan dien dung he thong song diidc chiing minh qua tinh chat quan khac la sii lech pha Co nghia la hieu dien the xoay chieu diidc dat vao mo song la U - Umax cos cot thi dong dien chay qua mo se bien thien nhii sau I = I max cos ( cot -cp) Goc lech pha cp noi len tinh chat “song” cua mo, mo chet th i cp- C) cac he sinh vat, ngiidi ta thay dac triing bdi gia tr i goc lech pha rat ldn Dieu chiing to rang vai tro cua dien dung cac he rat cao Thi du d tan so 103Hz goc lech pha cua mot so" do"i tiidng th i nghiem diidc nhii sau: Than kinh ech 64° Cd thd 65° Da ech 55° Da ngiidi 55° Can phai noi luon la gia tri cua goc lech pha cung nhii tong trd cua mo song rat co" Z dinh vung tan so" dong dien kha ldn Dieu co the giai thich nhii sau: cac doi tiidng sinh vat deu la he “dien trd thuan, dien dung” song dien dung khong phai la dien dung tinh ma la dien dung phan ciic Ta biet rin g doi vdi dien dung tinh C= const thi tan so" tang, dung khang Xc= l/C co giam, tong trd giam va goc lech pha tang Con doi vdi dien dung phan ciic, dung khang cua no mot khoang tan so" nao se khong thay doi Tren hinh 5.16 bieu dien sii thay doi tong trd Z vao lg co cua mo song, khoe (diidng cong 1) va cung cua mo nhiing da bi chet (diidng thang 2) Trong mo chet cac mang te" bao von dong vai tro cac “tu dien song” da bi pha huy, dd mo se chi gom dien trd thuan Sii bien thien tong trd vao tan so" cho phep danh gia siic song cua cac mo, cay ghep cac cd quan ngiidi ta cung co ap dung dieu Ngoai goc lech pha cp cung cung cap cac thong tin bo ich ve trang thai cua mo lgco Hinh 5.16 _ R1 C R2 Hinh 5.17 193 De danh gia kha nang dan dien cua te bao v& mo, ngtidi ta thudng xav dting nhiing sd vat ly tiidng diidng, nghia la mo hinh hoa tinh dan dien cua he thong song Hinh 5.17 ve sd vat ly ttidng diidng mot so' nha nghien ciiu de xu&'t Trong hinh, la dien trd thuan p h in noi bao, R2 la dien trd thuan phan gian b^o C la dien dung phan ctic, khong co dinh ma phu thuoc tan so dong dien 3.3 Nguy hiem dien Cac bien phap an toan dien 3.3.1 Nguy hiem dien Dong dien di qua cd the gay nen cac hieu iing sinh ly khac thuoc vao cac yeu to' cua dong dien Cac hieu iing sinh ly co the la cac ton thtidng hay cam giac dau ddn va nang thi co the d in den tti vong Mtic gay ton thtidng cho cd the cua dong dien phu thuoc chu yeu vao ctidng do, thdi gian di qua va dtidng din truyen dong dien cd the Thi du ve anh htidng cua dtidng d in truyen: - cac th i nghiem tren cho, dong dien qua vung tim lam chet v&t nhanh hdn dong dien qua trung khu than kinh - d ngtidi, quan sat tha'y tai nan nghiem hdn dong dien noi hai chi khac phia di qua long ngtic, ching han tti tay phai den chan trai Tuy nhien, cac yeu to' tren thi ctidng dong dien la yeu to' quyet dinh nghiem cua tac hai Kho co the tong quat dtidc, the hieu bao nhieu thi nguy hiem cho ngtidi, vi ctidng dong dien truyen qua cd the phu thuoc khong chi vao the hieu ma vao dien trd cua cd the va cac vat trung gian noi cd the vdi cac dien ctic nhti giay dep, quan ao, Khi cac dien ctic dtidc dat trtic tiep tren be mat cd the th i ldn cua dong dien chu yeu dtidc quyet dinh bdi dien trd cua da Dien trd cua da ve phan minh lai bi anh htidng rat manh bdi am da Thi du dien trd cua cd the dtidc tti tay sang tay bien thien tti 106 Ohm do'i vdi da rat kho xuong 1000 Ohm doi vdi da tidt, ttic la bien thien hang nghin lan Ben cd the dong dien dtidc dan truyen chu yeu theo cac mach mau va mach bach huyet, cac cd, mang bao boc cac true than kinh Cudng dong dien Hieu ung sinh ly The hieu tao nen dong dien, ung vdi dien trd cd the 10.000 n 1000 n mA NgUdng cam giac 10 V 1V mA MCrc “vo hai" cao nhat 50 V 5V 10 - 20 mA Bat dau hien ti/png “co cting cd" (ngUdng “khong buong”) 100-200 V 10 -2 V 50 mA Cam giac dau, co the ngat choang va kiet sire Tim, phoi van hoat dong 500 V 50 V 100-300 mA Rung that, tif vong neu keo dai them Ho hap van tiep dien 1000-3000 V 100-300V 6A Co "cung" co tam that, tiep theo sau la nhip dap tim binh thudng Ho hap te Net tam thdi Cd the bi bong 60.000 V 6000 V 194 Ngtidi ta da khao sat rat nhieu tren nhting ngtidi tinh nguyen ve cac hieu ting sinh ly ma dong dien gay tren cd the Bang d tren cho ta biet cac hieu ting sinh ly m& dong dien 60 Hz (tin so cua ltidi dien dan dung) d cac ctidng khac gay nen tren cd the truyen qua than ngtidi mot giay qua cac dien ctic dat tren da Thu^t ngti ngtidng “khong buong” (don’t let go) b it nguon tti hien ttidng sau, dong dien tren mtic gay sti co cting cd nam ban tay ma khong the duoi dtidc theo y muon Vi vay cac tai nan ve dien, neu tay tiep xue vdi vat dan dien xoay chieu (thtidng co da so' trtidng hdp) ngtidi bi nan thtidng bi giti chat vao vat dan dien, tti minh khong the ru t tay dtidc, do lam tr im them hau qua Ngtidng “khong buong” la mot thong so' quan trong, dong dien tren mtic dtidc coi la nguy hiem doi vdi ngtidi Do'i vdi dong xoay chieu, t in so' la mot yeu to' quyet dinh ldn ngtidng “khong buong” Do th i tren hinh 5.18 bieu dien mot cach ttidng do'i sti phu thuoc ngtidng “khong buong” va ngtidng cam giac cua ctidng dong dien vao lg f (f la tin so' dong dien truyen tti tay qua tay kia) Nhti ta co the tha'y tren thi, dong xoay chieu 50, 60 Hz dung rong rai khap ndi cuoc song co ngtidng nguy hiem thap nhat Ngtidc lai dong xoay chieu t in so ldn hdn 10.000 Hz ctidng phai rat ldn mdi nguy hiem do'i vdi cd the Dong dien co t in so' rat ldn iai co xu htidng gay bong Hinh 5.18 Moi nguy hiem ldn nhat cua dien la tac dung kich thich cd va th in kinh Doi vdi ddng dien mot chieu tacTlung chi xay dong, ngat mot mach dien co ctidng cao Trong cac tai nan dien mot chieu va ctidng dong dien tdi hang 195 chuc ampe, ngtidi bi dien giat co mot cam giac dau ddn dot ngot, co the bi choang tham chi co the ngat di mac dau nao chua trtic tiep bi kich thich Nhting tai nan chet ngiidi vi dien thiidng xay dot ngot, ngiidi bi nan nga xuong khong kip keu, sau vai giay, it tdi vai phut, ngiidi bi nan se chet Trong da so' triidng hdp chet vi dien giat, ngiidi ta thay xuat hien mot sti tang ap liic khong dot ngot diidng ho hap, co the dan den lam vd cac phe nang Ngoai thay xung huyet day dac d phoi va co phu phoi ntia Cac bo ph&n khac cung it nhieu bi xung huyet Tuy vay trai vdi quan niem triidc cho rang nguyen nhan chinh gay tii vong tai nan dien la te liet ho hap quan diem y hoc hien cho rang nguyen nhan gay tii vong bien la rung that Tim dac biet nhay cam vdi “giat dien” vi hoat dong bdm mau cua tim diidc dieu khien bdi cac xung dien sinh vat, cac xung dien co nguon goc ben ngoai cd the lam dao Ion sii dieu khien va gay hoat dong hon loan cac buong tim (rung that) Nhieu tac gia cd nhiing y kien khac ve cd che tong quat cua tai nan dien Mot nguy hiem khac cua dien la tac dung nhiet cua ddng dien Ta biet rang toan cd the va moi doan cd the deu cd mot tong trd vdi ddng dien mot chieu va ddng dien xoay chieu Vi vay ddng dien chay qua cd the, nhiet liidng toa tiing doan cd the phu thuoc vao ciidng ddng dien va tong trd cua doan cd the dd Chinh vi vay tinh trang bong cd the xuat hien doan cd the ma khong xuat hien d doan cd the khac 3.3.2 De phong tai nan dien 3.3.2.1 Nguyen nhan bi giat dien Dieu kien bat buoc de cd ddng dien truyen qua cd the la hai dien ctic co chenh lech dien the cung tiep xue vdi cd the Nhiing chim dau tren day dien cao the khong bi dien giat vi ca hai chan deu tiep xue vdi cung mot dien the Ngoi xe o to neu bi day cao the rdi vq.o xe cung khong vi lop xe cach dien xe vdi dat Trong ky thuat dien ngudi ta diing thuat ngii day “nong” de chi day din cd dien the khac khdng, day “nguoi” la day trung hoa, “dat” de chi mat dat cung cd dien the b&ng khdng Thong thudng day “nguoi” cua nguon dien dtidc noi dat Da so cac tai nan xay sti tiep xue cua nan nhan vdi day "nong’ cua nguon va ca vdi “dat” Thi du nhti chan tran di tren dat, tay vd y cham phai day “nong” 3.3.2.2 An toan dien sinh hoat va lam viec Ngay cuoc song quanh ta, cac may moc, thiet bi sti dung dien da rat bien Vi vay viec n im vting nhting nguyen tic de phong tai nan dien la rat can thiet do'i vdi moi ngtidi.Cac nguyen tic chinh de de phong va giam bdt miic nguy hiem cua tai nan dien la: Khong de tinh cd tao nen mach: day “nong” - cd the - “dat” Cu thi la, khdng lam viec chan tran tren nen dat, san am, can chu y rang day dep bang da cung dan dien, nhat la da am tidt, hoac giay, dep cd ddng nhieu dinh kim loai Vi vay giay, dep can giti kho va khong ddng dinh kim loai vao de Giay hoac dep 1Qfi cao su tot hdn ve mat an toan dien Tiidng am ddng vai trd “dat” hoac day “nong” neu nhu cd sii rd dien - Khdng cung luc cham hai tay (hay hai phan cua cd the) vao vo kim loai cua mot hay hai thiet bi dien Khi dang lam viec vdi thiet bi dien khdng cham tay vao cac vat kim loai xung quanh, lutu y rang tay lidt d in dien tot, tay khd van dan dien nhiing kem hdn Dung cac dung cu cd boc cach dien, cd the di gang cao su nhiing khdng diidc dung gang qua mong, de rach, gang cao su qua day lai lam giam chinh xac thao tac - Thiic hien noi dat tot cho cac thiet bi dien va cd kem cau chi Khi dien tu: bo phan ben cua may truyen vao vd kim loai cua may thi vo may trd day “nong” , neu vd khdng noi dat thi mot bo phan cua cd the tiep xue vdi vo may cd the dan den tai nan Vi vay can phai noi vd kim loai cua may vdi dat de cd dd dien vd nay, dien truyen xuong dat qua cau chi bao ve hoac bo phan cat dien til dong lam ngat dien vao may - Thiic hien cac bien phap cach ly cac cho nguy hiem cua mach dien bang cac vat cach dien hoac bang lildi kim loai cd noi dat - Tang ciidng giao due rong rai y thiic de phong tai nan dien bang cac hinh thiic van hoa quan chung, thong tin tuyen truyen Chu y dat cac bang tin hieu bao sii nguy hiem tai cac ndi yeu Kiem tra, nhac nhd can bo, cong nhan vien thiic hien tot cac bien phap de phong tai nan dien 3.3.2.3 An toan dien benh vien Ngoai cac kien thiic ve nguy hiem dien nhii da ndi d tren, chung ta rat can biet them mot dac thu khac cua nguy hiem dien linh vile y te Ngiidng nguy hiem cua ddng dien diidc de cap den (3.3.1) la do'i vdi triidng hdp ddng dien qua da vao cd the, ddng dien dd diidc phan bo rong theo cd the Trong triidng hdp cd day dan den thang tim thi ngiidng gay nguy hiem cua ddng dien se nhd hdn khoang mot nghin lan Trong th i nghiem vdi chd chi can 20 jiA da du gay nen sii rung that N hii vay cac benh nhan cd cac vat dan cam vao ngiidi, thi du nhii cac ong thdng, hut (catheter), cac kim truyen dich, va nhat la cac benh nhan diidc dat may tao nhip tim (pacemaker) la nhom “dac biet nhay cam” vdi dien Ngoai benh vien thiidng xuyen phai thiic hien cac phep ghi do, chieu chup dien nhii ECG, chup X quang va thiic hien cac lieu phap dien khac tren ngiidi benh nhan, vi vay an toan dien benh vien cang phai dac biet coi Sau day la mot so' qui tac an toan dien cac cd sd kham chiia benh: Tat ca cac thiet bi dien, chinh xac la cac vd dong cd dien may X quang may dien lieu phap, may ghi dien tim, may ghi dien nao, phai diidc noi dat Ngay h iu het cac thiet bi dien deu cd phich cam ba day de noi dat Tuy nhien phai kiem tra luon luon day ndi dat vi thiet bi van hoat dong diidc day noi dat hd Benh nhan khdng diidc tiep xue vdi dat, nhat la phai chu y de cac day d in va cac vat kim loai tren ngiid^ benh khdng cham dat Giiidng sat phai cd chan hay banh xe cao su each dien 197 Cac vo kim loai tran cua cac thiet bi dien phai cach xa tim vdi cua benh nhan Khi dang thtic hien cac phep dien hoac lieu phap dien cac day tiep xue vdi benh nhan phai dtidc cach dien rat tot vdi nguon Chu y: Bien phap thti nhat la quan nhat vi ba bien phap sau cd the de dang bi vi pham bat can Doi vdi nhom benh nhan “dac biet nhay cam” vdi dien nhti da noi d tren, cac nhan vien y te can ltiu y them: Khdng cham mot tay ban vao vat dan cam vao ngtidi benh, tay cham mot vat kim loai khac Nhd rin g luc dd mot ddng dien rat nhd (-5 jiA ) c6 the qua ban vao benh nhan ma mac du ban khdng cam giac dtidc nhting lai gay nen nguy hiem (rung that) cho benh nhan Dat toan bo cac thiet bi dien dang lien quan den cac benh nhan “dac biet nhay cam” vdi dien vao cac hop chtia hay tren cac de cach dien Trong cac benh vien hien dai cd loai gitidng chuyen dung danh cho nhom benh nhan nay, co bang dien rieng de phuc vu cac thiet bi dien Bien phap la toi tiu 3.4 Tac dung tich circ cua dong dien len cd the va ting dung y khoa Dien cung giong nhti nhieu yeu to' vat ly khac, neu tac dung vao cd the ngtidi vdi mtic thich hdp, dtidc theo doi va dieu chinh than se dan den nhting ket qua dtidng tinh, phu hdp vdi muc dich va Idi Ich cua ngtidi 3.4.1 Hieu ung ly-hoa-sinh cac mo cd ddng m ot chieu di qua Cac dung dich sinh ly chiem ty rat ldn cd the song, dd la moi trtidng dan dien vi dd hoa tan mot so' ltidng ldn cac i-on (chu yeu la vd cd): Na+, K+, Cl', Dtidi tac dong cua dien trtidng cac ion chuyen dong cd dinh htidng vdi cac to'c khac Cac phan tti htiu cd cd cau true ltidng ctic dien thi sip xep lai theo htidng dien trtidng Mat khac ton tai t nhieu mang ngan (mang te bao, mang cd, cac vach ngan gitia cac cd quan, ) nen cac ion khdng di chuyen tu dtidc, vi the tai vung lan can cac mang ngan xuat hien sti tap trung cac dien tich, ket qua la tao dien trtidng phan ctic d nhting vung chiu tac dung cua dien trtidng ngoai Sti phan bo lai cac dien tich nhti vay lam thay doi dien the mang va tinh tham cua mang te bao, anh htidng den qua trin h khuech tan va tham tha'u Nhieu chat binh thtidng khdng the qua mang thi de dang di chuyen qua Cac hoat dong trao doi chat cung dien manh hdn Tai cac ctic dien dat tren cd the xay cac phan ting dien phan Thi du nhu cac phan ting sau cua cac ion Na+ va Cl tai ctic am va ctic dtidng ttidng ting: Na+ + H 20 + e = NaOH + 1/2H2? 2C1 + HoO - e = 2HC1 +1/2CK 198 3.4.2 Ung dung cua ddng dien m ot chieu vat ly tri lieu x Trong vat 11 tri lieu ting dung cua dong dien mot chieu co the chia hai nhom chinh dtia theo dac diem dong dien dtidc sti dung 3.4.2.1 Dung ddng dien mot chieu khong doi - Lieu phap Galvani (galvanisation): Cho dong dien mot chieu deu di qua nhting vung can thiet tren cd the Hieu ting cuc bo tai vung cd the co dong dien di qua: cac mao mach dan ra, tinh tham cua cac mang te bao va cac mao mach tang len, nhd cac hoat dong trao doi chat dtidc tang ctidng, trtidng ltic cd giam, tuan hoan mau va bach huyet tang, ngoai sti tie t dich tai cac tuyen cung tang, tinh phan ting cua than kinh cam giac giam, Pham vi ting dung lieu phap Galvani la: chong viem, giam dau, gian mach, thuc day cac qua trin h tai tao, dieu hoa tiet dich, tang dinh dtidng, thti gian cd, Ngtidi ta thtidng dung hieu dien the khoang 60-80 V, vdi dieu kien phai tuan thu gidi han ctidng ddng dien cho phep do'i vdi cac vung khac tren cd the Thi du do'i vdi cac chi, ctidng toi da I MAX =20-30 mA tai vung mat I MAX = 3-5 mA, do'i vdi niem mac mui va mom la 2-3 mA Thdi gian cho ddng dien di qua cd the keo dai nhieu phut - Dien di (electrophoresis) cac dtidc chat: Cac dtidc chat dung dich bi phan ly cac ion, dat cac dung dich dd dien trtidng cac ion chtia dung dich se chuyen dong ve phia dien ctic tra i dau.Trong dieu tri ngtidi ta dung ddng dien mot chieu deu de dtia cac dtidc chat qua da va niem mac vao cd the De lam dieu ngtidi ta tam dung dich dtidc chat can thiet vao ldp boc cua mot dien ctic xac dinh so' hai dien ctic va thtic hien giong nhti Galvani lieu phap Dtidc chat se dtidc dtia vao tti ctic dien cd dau trung vdi dau ion phan tac dung cua thuoc H in h 5.19 Thi nghiem co dien sau cua Leduc minh hoa rat ro rang viec cac dtidc chat cd the tham nhap vao cd the qua da manh hdn nhieu dtidi tac dung cua ddng mot chieu Hai tho T 1( T2 dtidc cao sach long hai ben stidn, dat tiep xue gitia hai thd mot khoi bong C tam dung dich dtidc chat khao sat Hai ben stidn lai cua hai thd dat hai dien ctic rong noi vdi nguon dien m9t chieu nhti tren hinh 5.19 * strychnin, cho ddng dien cd 50-100 mA di qua vai phut, thd T] khdng thd T2 co giat chet vdi cac bieu hien dac trting bi nhiem doc chat strychnin Goc strychnin la ion dtio'ng dich chuyen ve ctic am lam thd T2 chet ma khong lam thd T, chet 199 * Neu C tam dung dich Kalicyanua (KCN), bay gid th i thd T2 khdng thd Tj chet vi goc cyanua la ion am di ve ctic dtidng Phtidng phap dien di cac dtidc chat hdp nh&'t dtidc ca tac dung cua ddng mot chieu lieu phap Galvani, ca tac dung cua dtidc chat, hdn the ntia ddng dien lam dtidc chat tham nhap sau hdn, tac dung lau hdn va cd mtic hoat dong manh hdn nhieu so vdi binh thtidng 3.4.2.2 Dung ddng xung dien Xung dien la ddng dien hoac hieu dien the ton tai thdi gian rat ng&n ddng xung dien la mot chuoi noi tiep cac xung dien giong Ddng xung dien dtidc dac trting bdi cac dti kien sau(hinh 5.20): - Thdi gian ton tai xung dien x: la khoang thdi gian keo dai cua mot xung - Chu ky ddng xung dien T: la khoang thdi gian tti b it dau mot xung cho den bat dau xung tiep theo - Tan so' ddng xung dien f = 1/T bang ddn vi Hec (Hz) - Bien xung dien hay ctidng xung dien: ldn ctic dai cua xung, b in g ddn vi mA, jjA., hay la mV, j^V - Dang cua xung dien, th i du nhti xung vuong (a), xung rang ctia (b), xung hinh thang (c), xung ham mu e (d), xung hinh chuong (e), M U m ax o ^ U x T ^ T - > / Hinh 5.20 Ngtidi ta dung cac loai ddng xung dien rat khac theo cac chi so' tren cho cac muc dich tri lieu khac Cach sti dung ddng xung dien mot chieu vat ly tri lieu ve cd ban cung giong nhti lieu phap Galvani Trong lieu phap cd them mot so nhting tac dung dieu tr i khac vdi lieu phap Galvani thi du nhti : an than, gay ngu, chong co that, klch thich cd va than kinh (trong phuc hoi chtic nang cac cd quan va mo), Ngtidi ta ket hdp dting ddng xung dien mot chieu vdi cham ctiu dien cham va thu dtidc ket qua to't 200 ... hoc 10 3 11 0 11 0 1. 1 Dao dong dieu hoa 11 1 1. 2 Dao dong tat dan 11 3 1. 3 Dao dong cUdng btic va hien tUdng c6ng hUdng 11 4 1. 4 Tong hdp va phan tich dao dong 11 6 Song cd hoc moi trUdng dan hoi 11 8... phan Tiep dau nguf Ky hieu Thira so Dexi d 10 '1 102 XSngti c 10 '2 k 10 3 Mili m 10 '3 Mega M 10 6 a 10 ‘6 Giga G 10 9 Nano n 10 '9 Tera T 10 12 Pico P 10 -12 Ky hieu ThCra so De ca da 10 1 Hecto h Kilo Tiep... nucleon 10 '24 Chu ky dao dong hat nhan 10 - 21 Chu ky dao dong nguyen tCr 10 ’ 14 Chu ky dao dong song vo tuyen truyen hinh 10 '8 Chu ky dao dong song am 10 -3 Nhip tim 1 nSm 10 8 Odi ngudi 10 10 X uat