X-ray tsom - txoj kev tshawb no ntawm cov qauv ntawm cov tshuaj

X-ray tsom xam yog ib tug qauv ntawm cov kev tshawb fawb ntawm cov yam ntxwv lub tsev ntaub ntawv. Nws yog raws li nyob rau hauv lub diffraction ntawm X-ray beam on tshwj xeeb crystalline peb-dimensional lattices. Nyob rau hauv txoj kev tshawb no siv ib tug yoj ntev uas yog kwv yees li 1A uas ua raws li qhov loj ntawm ib tug atom. Kuv yuav tsum hais tias lub X-ray tsom xam nrog neutron thiab electron diffraction txoj kev koom qhov kev txiav txim ntawm cov qauv ntawm cov tshuaj yeeb dej caw.

Nws yuav pab tau soj ntsuam cov atomic qauv, lub chaw pab pawg neeg ntawm tus xauj tsev ntawm tes, nws loj thiab cov duab, raws li zoo li ib tug pab pawg neeg uas siv lead ua symmetry. Siv cov txheej txheem no kawm ntau yam hlau thiab lawv cov alloys, organic thiab inorganic tebchaw, minerals, amorphous cov ntaub ntawv, dej thiab roj cua. Nyob rau hauv tej rooj plaub, ib tug X-ray qauv tsom xam ntawm cov nqaijrog, nucleic acids thiab lwm yam.

Qhov no tsom xam yuav pab tsim kom muaj cov atomic qauv ntawm crystalline ntaub ntawv uas muaj ib tug zoo-txhais qauv thiab yog ib tug natural diffraction grating rau x-rays. Nws yuav tsum tau muab sau tseg tias kev tshawb nrhiav lwm yam duab tshav tsom xam yuav tsum tau muaju, uas yog ib qho tseem ceeb tab sis nyuaj txaus.

Lub diffraction ntawm X-rays sab los ntawm cov Laue, lub theoretical lub hauv paus ntawm Hma thiab tsim Bragg. Thov qauv pom nyob rau hauv lub luag hauj lwm ntawm tus tsom xam uas muab los ntawm Debye thiab Scherrer. Kuv yuav tsum hais tias nyob rau hauv tam sim no lub X-ray tsom xam yog ib qho ntawm feem ntau txoj kev rau kev txiav txim cov qauv ntawm cov tshuaj, vim hais tias nws yog yooj yim ua thiab tsis yuav tsum tau tseem ceeb kev siv nyiaj txiag.

Nws tso cai rau koj mus tshawb kawm txawv ntawm yam, thiab tus nqi ntawm cov ntaub ntawv uas tau ua rau cov kev taw qhia tshiab hom kev kawm. Yog li, ua ntej pib mus kawm ntawv cov qauv ntawm cov tshuaj yeeb dej caw thaum uas siv cov interatomic vectors tom qab direct txoj kev txiav txim lub crystalline lug tsim. Nws yuav tsum tau muab sau tseg tias thawj yam uas tau kawm siv X-rays tau sodium thiab potassium chlorides.

Txoj kev tshawb no ntawm lub spatial qauv ntawm cov nqaijrog pib nyob rau hauv lub 30s ntawm lub xeem caug xyoo nyob rau hauv lub tebchaws United Kingdom. Cov ntaub ntawv tau yog muab sawv ntawm molecular biology, uas tso cai rau kom paub tias tseem ceeb physico-tshuaj thaj chaw ntawm cov nqaijrog, raws li zoo raws li DNA los tsim thawj qauv.

Nrog rau 50-ies nquag pib tsim computer los ua ke kev kawm ntawm cov ntaub ntawv uas tau raug muab los ntawm X-ray ntxwv tsom xam.

Rau hnub tim, siv synchrotrons. Lawv yog cov monochromatic qhov chaw ntawm X-rays yog siv rau cov irradiation ntawm cov muaju. Qhov zoo tshaj cov pab kiag li lawm yog siv cov qauv ntawm cov multi-wavelength anomalous dispersion. Nws yog ib nqi sau cia hais tias lawv thov xwb rau pej xeem kev tshawb fawb chaw. Nyob rau hauv lub chaw soj nstuam siv tsis haib txheej txheem uas ua hauj lwm pab xwb kom paub tseeb qhov zoo ntawm cov muaju, thiab kuj yuav muab tau ib coarse tsom xam ntawm tshuaj.