Lub magnetic teb yog uniform thiab tsis niaj hnub zoo li: characterization thiab kev qhia kom paub

Ib tug ntawm cov tswv yim siv nyob rau hauv physics, yog lub magnetic teb. Nws ua rau cov tsiv fais nqi. Tsis paub thiab yog tsis muaj los ntawm tus txiv neej, tab sis nws muaj peev xwm yuav ntes tau los ntawm ib tug magnet los yog ib tug hlau. Nws tseem yog ib qho yooj yim txaus los to taub yuav ua li cas lub sib nqus teb no yog hu ua homogeneous thiab heterogeneous.

Identification thiab nrhiav kom tau txoj kev sib nqus teb

Thaum peb ntsib nrog lub tswvyim ntawm ib tug sib nqus teb, peb muaj ib lo lus nug txog dab tsi zoo ntawm no magnetic teb, niaj hnub los yog uas tsis yog niaj hnub zoo li nws. Ua ntej teb lo lus nug no, nws yog tsim nyog los mus txiav txim thawj zaug cov lus.

Lub magnetic teb no yog lam xav mus xav txog ib tug tshwj xeeb ntawm cov ntaub ntawv uas twb muaj lawm nyob ze ntawm lub tsiv fais nqi, tshwj xeeb tshaj yog nyob ze ntawm lub tam sim no-nqa conductors. Koj yuav nrhiav tau los ntawm kev siv ib tug sib nqus koob los yog hlau filings.

homogeneous teb

Nws pom hauv ib tug sawb hlau nplaum thiab lub solenoid, thaum qhov ntev yog loj dua lub taub. Nyob rau hauv cov ntaub ntawv no, cov kev cai ntawm cov ntiv tes xoo nkhaus ntawm lub magnetic teb yuav tsum tau qhia counterclockwise.

Sib Nqus kab yog thaum uas tig mus thiab ncaj, lub emptiness ntawm lawv yeej tib yam nkaus, lub hwj chim ntawm lub hwj lub magnetic koob tsis txawv rau tag nrho cov ntsiab lus nyob rau hauv nws cov magnitude thiab cov kev taw qhia.

inhomogeneous teb

Nyob rau hauv cov ntaub ntawv ntawm ib tug inhomogeneous magnetic teb kab yuav tsum khoov duav, tus tsis muaj dabtsis therebetween yog txawv nyob rau hauv qhov ntau, tus quab yuam ntawm tej yam nyob rau hauv lub nqus koob txawv txawv cov ntsiab lus nyob rau hauv nws daim teb magnitude thiab cov kev taw qhia. Tsis tas li ntawd, tus quab yuam sawv lub sawb yog muab tso rau hauv cov hlau nplaum teb xub, ua nyob rau hauv txawv cov ntsiab lus uas sib txawv nyob rau hauv qhov ntau thiab cov kev taw qhia ntawm cov rog. Qhov no yog hu ua ib tug inhomogeneous teb. Lub teb kab no nkhaus li xws li, lub zaus mas nws txawv ntawm taw tes rau taw tes.

Mus ntes no zoo ntawm daim teb, tej zaum nyob ze ntawm lub direct tam sim no-nqa neeg xyuas pib, ib tug sawb hlau nplaum thiab ib tug solenoid.

Yuav ua li cas yog sib nqus kab

Nyob rau hauv thawj qhov chaw thaum ib tug neeg ua hauj lwm yuav tsum txiav txim seb ib tug sib nqus teb uas yog homogeneous los yog inhomogeneous, yog tsim, nws yuav tsum qhia hais tias tus magnetic kab, tus duab uas yuav kom meej rau tus yam ntxwv.

Yuav kom depict magnetic teb pib siv magnetic kab. Lawv yog cov xav txog tej yam ib daim hlab nyob raws lub magnetic rab koob thiab muab tso rau hauv ib tug sib nqus teb. Tuav ib tug sib nqus kab yog ua tau los ntawm tej taw tes ntawm lub teb, nws yuav tsum yog tus coj thiab yeej ib txwm nyob ze.

kev taw qhia

Tuaj tawm ntawm lub sab qaum teb ncej ntawm ib tug magnet thiab xa mus rau sab qab teb. Lub sab hauv ntawm cov hlau nplaum tag nrho nruj me ntsis rov qab. Cov kab tsis muaj ib tug pib los yog qhov xaus, yog kaw los yog los ntawm infinity rau infinity.

Sab nraum lub magnet kab yog cov feem ntau densely nyob ze tug. Los ntawm no nws yuav paub tseeb hais tias feem ntau xav cuam tshuam rau lub teb nyob ze ntawm lub tug, thiab qhov kev ncua deb ntawm lub hauv qab ntawm nws tsis muaj zog. Muab hais tias lub magnetic ib daim hlab yog nkhaus, cov kev taw qhia ntawm kev quab yuam sawv ib tug sib nqus koob, yog tseem hloov.

Yuav ua li cas mus rau kos

Yuav kom to taub qhov txawv ntawm ib tug niaj hnub magnetic teb ntawm ua kev, nws yuav tsum kawm kom qhia siv magnetic kab.

Piv txwv li tshwm sim niaj hnub magnetic teb yuav tsum raug xam tias yog nyob rau hauv lub saum toj no npe hu li-hu ua solenoid uas yog ib tug cylindrical hlau kauj los ntawm kev uas tam sim no yog tso cai. Hauv nws, ib tug sib nqus teb yuav suav hais tias homogeneous, muab hais tias qhov ntev yog loj dua txoj kab uas hla (sab nraum teb coils yuav tsis niaj hnub, nqus cov kab yuav tsum muab tso rau raws li zoo raws li lub band-pass magnet).

Uniform teb no yog tseem nyob rau hauv qhov chaw ntawm lub ruaj khov magnet sawb. Nyob rau hauv ib tug tsawg cheeb tsam nyob rau hauv qhov chaw no yog tau rau cov me nyuam thiab niaj hnub magnetic teb, nyob rau hauv uas tej yam quab yuam nyob rau hauv ib tug magnetized xub yuav ua ncaj nyob rau hauv qhov ntau thiab cov kev taw qhia.

Yuav kom depict magnetic teb, siv raws li nram no piv txwv. Yog hais tias txoj kab yuav tsum tau nyob perpendicular mus rau lub nqus dav hlau thiab yog qhia los ntawm cov beholder, lawv depict crosses, yog hais tias tus beholder - cov ntsiab lus. Raws li qhov tam sim no, txhua tus ntoo khaub lig yog zoo li ib tug pom tus Tsov tus tw ya los nrhiav sub, thiab tus taw tes - ntse sub, uas yoov rau peb.

Cov yuav tsum tau "Kos ib yam thiab uas tsis yog-uniform magnetic teb" yog yooj yim phaaj tseem ceeb hab. Cias kos cov magnetic kab ntawm lub teb muab tus yam ntxwv (homogeneous thiab inhomogeneous).

Txawm li cas los, cov hav zoov uas tsis yog niaj hnub zoo li teb zoo heev complicates neeg ua hauj lwm. Nyob rau hauv xws li ib embodiment, qhov kev npaj ntawm ib tug lub cev tshwm sim siv cov kev equation tsis zoo li.

sib txawv

Cov lus teb rau lo lus nug txog qhov sib txawv ntawm ib tug niaj hnub magnetic teb ntawm ua kev, yooj yim txaus los muab. Ua ntej ntawm tag nrho cov nws nyob rau hauv lub magnetic teb kab. Nyob rau hauv cov ntaub ntawv ntawm ib tug niaj hnub teb qhov kev ncua deb nruab nrab ntawm lawv yuav tsum yog tib yam, thiab lawv yog tusyees muab tso rau, nrog rau cov tib quab yuam sawv nyob rau hauv li ntawm tej taw tes. tag nrho cov nruj me ntsis rau cov uas tsis niaj hnub teb rov qab. Kab unevenly nyob rau hauv qhov chaw sib txawv ua nrog teej yuam rau ntawm lub pab kiag li lawm.

Nyob rau hauv kev xyaum, feem ntau nws tshwm sim inhomogeneous teb, raws li tau zoo raws li nyob rau hauv kom lub siab, vim hais tias homogeneous teb yuav tshwm sim tsuas yog nyob rau hauv lub khoom, xws li ib tus hlau nplaum los yog ib tug solenoid. Sab nraud xyuas yuav sau cov heterogeneity.

kom paub tias teb

Realizing hais tias xws li ib tug uniform thiab tsis niaj hnub zoo li magnetic teb, thiab kev txiav txim lawv rhuav yuav tsum paub nyob rau hauv dab tsi txoj kev uas koj muaj peev xwm ntes lawv.

Cov feem ntau yooj yim rau qhov no yog qhov xyaum ua tej yam ua los ntawm Oersted. Nws muaj nyob rau hauv cov kev siv ntawm cov magnetic koob, uas yuav pab tau txiav txim lub hav zoov ntawm ib tug hluav taws xob tam sim no. Thaum cov tam sim no yuav taug kev los ntawm cov neeg xyuas pib nyob ze ntawm lub xub tau tsiv mus nyob, vim lub fact tias muaj yog homogeneous thiab inhomogeneous magnetic teb.

Sis nrog tam sim no conductors

Txhua tam sim no-nqa neeg xyuas pib cai nws magnetic teb, sawv nrog ib tug tej kev quab yuam rau tom ntej no. Nyob rau hauv lub tam sim no cov kev taw qhia, lub conductors yuav attracted los yog repelled los ntawm txhua lwm yam. Lub teb ze ntawm qhov chaw sib txawv thiab yuav muab tais mus ua ib lub ib ua teb.

Yuav ua li cas yog li cas thiab

Piv txwv ntawm homogeneous thiab inhomogeneous magnetic teb thov nyob rau hauv lub cathode txoj sab ci raj, yog coils uas tam sim no yog dhau lawm. Yuav kom muab tau cov kev kawm zoo ntawm tus magnetic teb thov shelving lugs thiab sib nqus shields ua los ntawm fabrics muaj ib tug muaj zog sib nqus permeability.

Nyhuv ntawm inhomogeneous magnetic teb muaj peev xwm hloov lub chav kawm ntawm irreversible tshwm sim ntawm lub cev thiab tshuaj xwm, feem ntau ua kev txheej txheem. Cov tsos ntawm turbulent diffusion ua rau ib qho kev nce ntawm ob peb kev txiav txim ntawm qhov ntau cov kev ceev ntawm lub zog ntawm cov roj los ntawm ib cov kua rau ib tug saum npoo nyob rau hauv daim ntawv ntawm cov microbubbles. Cov nyhuv ntawm lub zos lub cev qhuav dej thiab ion hais vim microcrystallization txheej txheem intensification. Nyob rau hauv siab zog xov xwm txaus cov tshuaj tiv thaiv muaj peev xwm ntawm cov dawb radicals, singlet oxygen, peroxide thiab nitrogen tebchaw. Nws tshwm sim coagulation, thiab kua khoom uas tshwm sim los ntawm kev puas tsuaj yaig.

Thaum lub sij hawm hydrodynamic cavitation loj nqi ua npuas thiab kab noj hniav complicates lawv Entrainment ntawm cov kua los ntawm qhov chaw ntawm tsis tshua muaj siab nyob rau hauv lub siab siab tsam nyob qhov twg lub collapsing npuas yog ua. Thaum lub sij hawm lub cev qhuav dej ntawm lub me me kom muaj nuj nqis ntawm cov npuas muaj tsawg cua cov ntsiab lus thiab muaj ib tug muaj zog tshuaj cov tshuaj tiv thaiv zoo xws li cov ntshav tawm. Lub xub ntiag ntawm uas tsis yog niaj hnub sib nqus teb ua rau muaj kab noj hniav tsis khov, lawv disintegration thiab cov emergence ntawm me me-scale vortices thiab npuas. Muab hais tias lub siab nyob rau ntawm qhov chaw ntawm lub vortex yog nws txo qis, nws yog hloov dua siab tshiab nyob rau hauv loj me me roj npuas.

Thaum lub sij hawm induction ntsuam nyob rau hauv ib tug nonuniform magnetic teb yuav tsum tau nco ntsoov tias Hall voltage yog xwm yeem mus rau qhov ntau ntawm cov sim teb lub dag lub zog nyob rau hauv lub cheeb tsam bounded los ntawm cov transducer nto.

Ua kom pom tseeb rau hauv lub paraxial beams no kuj siv uas tsis yog-uniform magnetic teb tsim los ntawm luv luv coils yog multilayer coils, qhov ntev ntawm uas yog commensurate nrog txoj kab uas hla thereof. Ib tug electron ntog nyob rau hauv xws li ib tug teb, rog, hloov nws cov kev taw qhia. Hauv pawg los ntawm xws li rog nce lub lens axis, nrog lub dav hlau nyob rau hauv uas nws muaj nws cov trajectory yog nkhaus. Lub electron tsiv los ntawm spiraling ya uas tshuam lub lens axis ntawm ib tug muab point.

Spatial tau nce yog tshwm sim los ntawm inhomogeneous spatial rassredotachivaniem teb nyob rau hauv ib ncig ntawm ib tug ua kev system, eclipsing kua. Yog xav tau ib tug pej xeem inversion theem sib cais txoj kev thov inhomogeneous teb tsim multiband magnet. ncej puab yog zoo li tus pas nuv ntses nyob rau hauv ib tug quadrupole capacitor molecular oscillator siv ammonia.

Txoj kev ntawm qhov kev siv

Sib Nqus khuam kom paub tias txoj kev ib theem raws li nyob rau hauv lub traction quab yuam ntawm cov magnetic hais tsis yog niaj hnub zoo li teb uas yuav tshwm sim nyob rau hauv lub tsis xws luag. By txuam nrog ntawm tej hmoov ascertain lub xub ntiag ntawm ib tug kho raws, nws loj thiab txoj hauj lwm nyob rau hauv lub luam khoom.

Txiav txim siab disadvantage ntawm cov qauv ntawm cov molecular beams nrog ib tug xav inhomogeneous magnetic teb yog suav tias yog ib tug me me nyhuv cleavage. Muaj yog ib tug yooj yooj yim thiab seemingly implausible txoj kev ua cov nyhuv. Nws muaj nyob rau hauv daim ntawv thov ntawm cov sab nraud magnetic teb lub teeb. Cov yav tas yuav ua rau nws tau ua rau kom cov kev siv ntawm nuclear precession magnetometers nyob rau hauv cov kev taw qhia ntawm tsis niaj hnub sib nqus teb.

Qhov kom zoo dua ntawm no txoj kev yog lub siab daws lub hwj chim, ua rau nws tau mus kho cov inhomogeneous magnetic teb commensurate nrog rau cov nqi ntawm cov magnetic particle txheej daim kab xev, thiab tau nrhiav cov kev puas tsuaj rau txoj chaw thiab kaw lub keeb.

Qhov tsis zoo yog qhov yuav tsum tau ntawm theem nrab ua cov ntaub ntawv kaw tseg xwb hais ntawm magnetic teb raws txoj siv, cov complexity thiab khaws cia demagnetization daim kab xev thiab yog tsim nyog los tiv thaiv kom txhob tus ntawm lwm magnetic teb.

Lub magnetic teb yog uniform thiab tsis niaj hnub zoo li yog haum ntau, txawm lub fact tias cov invisible yooj yim neeg nyob li. Piv txwv ntawm homogeneous thiab inhomogeneous magnetic teb yuav raug kuaj nyob rau hauv bandpass hlau nplaum thiab solenoids. Nyob rau hauv cov ntaub ntawv no, lawv yuav tsum tau pom los ntawm kev siv ib tug yooj yim magnetic koob los yog hlau filings.