Izakhiwo Zikagesi Nezokushisa Zensimbi
Izinsimbi zitholakala yonke indawo ekuphileni kwethu kwansuku zonke, zisebenza izindima ezibalulekile ezinhlobonhlobo zezicelo, kusukela ekwakheni nasekuthuthweni kuya kuma-elekthronikhi nasezintweni zasekhishini. Esinye sezizathu ezibalulekile zalokhu kusetshenziswa kabanzi yinhlanganisela eyingqayizivele yezakhiwo zikagesi nezokushisa ezinazo izinsimbi. Ukuqonda lezi zakhiwo kubalulekile konjiniyela, ososayensi, kanye nabathandi abafisa ukusebenzisa ngokugcwele amandla alezi zinto. Lesi sihloko sihlola izakhiwo zikagesi nezokushisa zezinsimbi, sinikeza ukuhlola okujulile kwalokho okwenza lezi zinto zibe semqoka kangaka.
Izakhiwo zikagesi
Ukusebenza kukagesi
Ikhono lezinsimbi lokuqhuba ugesi lingenye yezici zazo eziphawulekayo. Lesi sici singabangelwa kakhulu ukuba khona kwama-electron akhululekile ngaphakathi kwe-lattice yensimbi. Eziningi zezinsimbi, ama-electron angaphandle ama-athomu awaboshelwe kunoma iyiphi i-athomu ethile futhi angahamba ngokukhululeka kulo lonke isakhiwo sensimbi. Lawa ma-electron ahlukaniswe asebenza njengabathwali bezimali, avumela ugesi ukuthi ugeleze ngensimbi lapho kusetshenziswa insimu kagesi.
Izinto ezifana nesiliva, ithusi, negolide zaziwa ngokusebenza kahle kakhulu kukagesi. Ithusi, ikakhulukazi, lisetshenziswa kakhulu ekuxhunyweni kukagesi ngenxa yokuqhuba kwalo okuphezulu kanye nezindleko eziphansi uma kuqhathaniswa nesiliva negolide. Ukuqhuba kukagesi (σ) kwezinsimbi kungalinganiswa kusetshenziswa ifomula:
\[ \sigma = \frac{1}{\rho} \]
lapho u-ρ ewukumelana kwezinto. Izinsimbi zivame ukuba namanani aphansi okumelana, ngokuvamile kusukela ku-\(10^{-8} \) kuya ku-\(10^{-6} \) ohm-meters, okwenza zibe abaqondisi bakagesi abaphumelelayo.
Ukwencika kwezinga lokushisa
Ukumelana kukagesi kwezinsimbi kuncike ekushiseni, ngokuvamile kuyanda ngokushisa. Lobu budlelwano buvame ukuvezwa kusetshenziswa ukulinganisa okulandelayo okuqondile:
\[ \rho(T) = \rho_0 [1 + \alpha (T – T_0)] \]
lapho:
– \(\rho_0\) ukuqina kokumelana ekushiseni okubhekiselwe ku-\(T_0\), okuvame ukubhekwa njengokushisa kwegumbi.
– \(\alpha\) yisilinganiso sokushisa sokumelana.
– \(T\) izinga lokushisa.
Ukwanda kokumelana nokushisa kungenxa yokudlidliza kwe-lattice okwandisiwe, okuphazamisa ukugeleza kwama-electron amahhala. Njengoba izinga lokushisa likhuphuka, ama-athomu e-lattice yensimbi ayadlidliza ngamandla amakhulu, okubangela ukushayisana okuvamile phakathi kwama-electron amahhala nama-ion e-lattice, ngaleyo ndlela kwandisa ukumelana nokugeleza kwama-electron.
I-Superconductivity
Ezinye izinsimbi, njenge-mercury kanye ne-lead, zibonisa ukushintshela kwesigaba esimweni sokuqhuba i-superconducting emazingeni okushisa aphansi kakhulu. Kulesi simo, izinto ezibonakalayo azibonisi ukumelana kukagesi kanye nokuxoshwa kwamasimu kazibuthe (umphumela we-Meissner). I-Superconductivity iyinto ye-quantum mechanical ebangelwa ukwakheka kwama-Cooper pair—ama-pair ama-electron aboshwe ndawonye emazingeni okushisa aphansi ngokudlidliza kwe-lattice.
Izakhiwo ezishisayo
Ukuqhuba Ukushisa
Izinsimbi zaziwa nangokuqhuba kwazo ukushisa okungavamile. Lesi sici sihlobene kakhulu nokuqhutshwa kwazo kagesi ngenxa yomthetho we-Wiedemann-Franz, othi isilinganiso sokuqhutshwa kokushisa (κ) nokuqhutshwa kukagesi silingana nokushisa:
\[ \frac{\kappa}{\sigma} = LT \]
lapho:
– \(L\) yinombolo yeLorentz, cishe \(2.44 \izikhathi eziyi-10^{-8} \) WΩK⁻².
– \(T\) izinga lokushisa ku-Kelvin.
Ngakho-ke, izinsimbi ezikwazi ukuqhuba kahle ugesi zivame ukuba yiziqhubi ezinhle zokushisa. Isiliva, ithusi, negolide ziphakathi kweziqhubi ezinhle kakhulu zokushisa, ngezinhlelo zokusebenza ezisukela ezishintshisani zokushisa kuya ezitsheni zokupheka.
Amandla Okushisa
Umthamo wokushisa wento ubonisa ikhono layo lokugcina ukushisa. Izinsimbi zinamandla okushisa aphansi uma kuqhathaniswa nezingezona izinsimbi, okusho ukuthi azigcini ukushisa okukhulu. Umthamo othize wokushisa (C) wensimbi unikezwa yi:
\[ C = \frac{Q}{m \Delta T} \]
lapho:
– \(Q\) inani lokushisa elingeziwe.
– \(m\) isisindo sensimbi.
– \(\Delta T\) ushintsho lokushisa.
Lawa manani ngokuvamile awaguquguquki ekushiseni kwegumbi kodwa angahluka emazingeni okushisa aphansi kakhulu noma aphezulu.
Ukunwetshwa Okushisayo
Esinye isici esibalulekile sokushisa kwezinsimbi ukwanda kokushisa, okuwukuthambekela kwezinto ukuthi zande lapho zishisa. Lesi sici senzeka ngoba njengoba izinga lokushisa likhuphuka, amandla e-kinetic ama-athomu ensimbi nawo ayanda, okubangela ukuthi adlidlize kakhulu futhi athathe isikhala esiningi. I-coefficient eqondile yokwanda kokushisa (α) inikezwa yi:
\[ \Delta L = \alpha L_0 \Delta T \]
lapho:
– \(\Delta L\) ushintsho lobude.
– \(L_0\) ubude bokuqala.
– \(\Delta T\) ushintsho lokushisa.
Izinsimbi zinezilinganiso eziphakeme kakhulu zokwanda kokushisa, okumele zicatshangelwe ekusetshenzisweni okubandakanya ukuguquguquka kwezinga lokushisa ukuze kugwenywe ukuguquguquka kwesakhiwo.
Izicelo Ezisebenzayo
Inhlanganisela eyingqayizivele yezakhiwo zikagesi nezokushisa yenza izinsimbi zibe yinto ebalulekile ezimbonini eziningi. Nazi izibonelo ezimbalwa zezicelo zazo:
– Ama-elekthronikhi: Ithusi negolide kusetshenziswa kakhulu kumasekethe kagesi ngenxa yokuqhuba kwawo kahle kakhulu kanye nokuthembeka.
– Ukudluliselwa Kwamandla: I-Aluminium, yize ingahambisi kakhulu kunethusi, ivame ukusetshenziswa emigqeni yokudlulisela kagesi ngenxa yesisindo sayo esiphansi kanye nokusebenza kahle kwezindleko.
– Izinki Zokushisa: Izinsimbi ezifana nethusi ne-aluminium zisetshenziswa ezinkini zokushisa ukuze kususwe ukushisa okuvela ezingxenyeni zikagesi, kugcinwe amadivayisi esebenza futhi kuvinjelwe ukushisa ngokweqile.
– Izimoto Nezindiza: Izinsimbi ezilula njenge-aluminium ne-titanium zisetshenziswa ezimbonini zokuthutha ukunciphisa isisindo ngenkathi kugcinwa ubuqotho besakhiwo kanye nokusebenza kokushisa.
Isiphetho
Izakhiwo zikagesi nezokushisa ezingavamile zensimbi zivela ezakhiweni zazo ze-athomu ezihlukile kanye nokuziphatha kwama-electron akhululekile ngaphakathi kwazo. Lezi zakhiwo azichazi nje kuphela ukuziphatha okuyisisekelo kwensimbi kodwa futhi zilawula ukusetshenziswa kwazo okusebenzayo. Intuthuko kwesayensi yezinto ezibonakalayo iyaqhubeka nokuthola izindlela ezintsha zokuthuthukisa nokusebenzisa lezi zakhiwo, okuthembisa ukusetshenziswa okusha kakhulu kwezinsimbi esikhathini esizayo. Ukuqonda lezi zakhiwo kusenza siqonde ukuthi kungani izinsimbi zihlala ziyizinto eziyisisekelo kwezobuchwepheshe kanye nasembonini.
