labarai

Na gode da ziyartar yanayi.Sigar burauzar da kuke amfani da ita tana da iyakataccen tallafi ga CSS.Don ƙwarewa mafi kyau, muna ba da shawarar ku yi amfani da sabon sigar mai binciken (ko kashe yanayin dacewa a cikin Internet Explorer).A lokaci guda, don tabbatar da ci gaba da goyan baya, za mu nuna shafuka ba tare da salo da JavaScript ba.
Abubuwan maganadisu na SrFe12O19 (SFO) hexaferrite mai wuya ana sarrafa su ta hanyar hadaddun alaƙar microstructure ɗin sa, wanda ke ƙayyadad da dacewarsu ga aikace-aikacen maganadisu na dindindin.Zaɓi rukuni na SFO nanoparticles da aka samu ta hanyar sol-gel ba tare da bata lokaci ba, kuma kuyi zurfin tsarin X-ray foda diffraction (XRPD) halayyar G (L) nazarin bayanan martaba.Rarraba girman kristal da aka samu yana bayyana tabbataccen dogaro da girman tare da jagorar [001] akan hanyar haɗin gwiwa, wanda ke haifar da samuwar kristal mai walƙiya.Bugu da ƙari, an ƙaddara girman SFO nanoparticles ta hanyar nazarin microscopy na lantarki (TEM), kuma an kiyasta matsakaicin adadin crystallites a cikin barbashi.An kimanta waɗannan sakamakon don kwatanta samuwar jihohin yanki guda a ƙasa da mahimmancin ƙima, kuma ƙarar kunnawa ta samo asali ne daga ma'aunin maganadisu na dogaro da lokaci, da nufin haɓaka tsarin jujjuyawar maganadisu na kayan maganadisu mai wuya.
Nano-sikelin Magnetic kayan suna da babban kimiyya da fasaha ma'anar, domin su Magnetic Properties suna nuna mabanbanta halaye idan aka kwatanta da girman girman su, wanda ya kawo sabon ra'ayi da aikace-aikace1,2,3,4.Daga cikin kayan nanostructured, M-type hexaferrite SrFe12O19 (SFO) ya zama ɗan takara mai ban sha'awa don aikace-aikacen maganadisu na dindindin5.A gaskiya ma, a cikin 'yan shekarun nan, an gudanar da aikin bincike mai yawa akan gyare-gyaren kayan aikin SFO akan nanoscale ta hanyar nau'i-nau'i daban-daban da kuma hanyoyin sarrafawa don inganta girman girman, ilimin halittar jiki, da kayan magnetic6,7,8.Bugu da ƙari, ya sami kulawa sosai a cikin bincike da haɓaka tsarin haɗin gwiwar musayar9,10.Babban magnetocrystalline anisotropy (K = 0.35 MJ / m3) daidaitacce tare da c-axis na hexagonal lattice 11,12 sakamakon kai tsaye na hadaddun daidaituwa tsakanin magnetism da tsarin crystal, crystallites da girman hatsi, ilimin halittar jiki da rubutu.Don haka, sarrafa halayen da ke sama shine tushen cika takamaiman buƙatu.Hoto na 1 yana kwatanta nau'in sararin samaniya na hexagonal P63 / mmc na SFO13, da kuma jirgin da ya dace da tunanin nazarin bayanan martaba na layi.
Daga cikin halayen da ke da alaƙa na raguwar girman barbashi na ferromagnetic, samuwar jihar yanki guda ɗaya a ƙasa da ƙimar mahimmanci yana haifar da haɓakar anisotropy magnetic (saboda babban yanki mai girma zuwa girman rabo), wanda ke haifar da filin tilastawa14,15.Faɗin yanki da ke ƙasa da ma'auni mai mahimmanci (DC) a cikin kayan aiki mai wuya (ƙimar ta al'ada shine kusan 1 µm), kuma an ayyana shi ta hanyar abin da ake kira girman haɗin kai (DCOH) 16: wannan yana nufin mafi ƙarancin hanyar ƙararrawa don lalatawa a cikin girman daidaituwa. (DCOH), An bayyana azaman ƙarar kunnawa (VACT) 14. Duk da haka, kamar yadda aka nuna a cikin Hoto 2, kodayake girman crystal ya fi girma fiye da DC, tsarin jujjuyawar na iya zama rashin daidaituwa.A cikin abubuwan nanoparticle (NP), mahimmancin ƙarar juzu'i ya dogara da ɗanɗanon maganadisu (S), kuma dogaro da filin maganadisu yana ba da mahimman bayanai game da tsarin sauyawa na NP magnetization17,18.
A sama: Tsarin tsari na juyin halittar filin tilastawa tare da girman barbashi, yana nuna daidaitaccen tsarin jujjuyawar maganadisu (wanda aka daidaita daga 15).SPS, SD, da MD sun tsaya don superparamagnetic jihar, yanki guda, da multidomain, bi da bi;Ana amfani da DCOH da DC don haɗin kai da diamita mai mahimmanci, bi da bi.A ƙasa: Zane-zane na barbashi masu girma dabam, yana nuna haɓakar crystallites daga kristal guda ɗaya zuwa polycrystalline.kumanuna crystallite da barbashi size, bi da bi.
Duk da haka, a kan nanoscale, an gabatar da sababbin abubuwa masu rikitarwa, irin su hulɗar maganadisu mai karfi tsakanin barbashi, rarraba girman, siffar barbashi, rashin lafiyar jiki, da kuma jagorancin sauƙi na magnetization, duk abin da ya sa bincike ya fi kalubale19. 20 .Wadannan abubuwa suna tasiri sosai akan rarraba shingen makamashi kuma sun cancanci kulawa da hankali, don haka suna shafar yanayin jujjuyawar maganadisu.A kan wannan, yana da mahimmanci musamman don fahimtar alaƙar da ke tsakanin ƙarar maganadisu da nanostructured M-type hexaferrite SrFe12O19.Sabili da haka, a matsayin tsarin ƙira, mun yi amfani da saitin SFOs da aka shirya ta hanyar hanyar sol-gel ta ƙasa, kuma kwanan nan mun gudanar da bincike.Sakamakon da ya gabata ya nuna cewa girman kristal yana cikin kewayon nanometer, kuma shi, tare da siffar crystallites, ya dogara da maganin zafi da aka yi amfani da shi.Bugu da ƙari, crystallinity na irin waɗannan samfurori ya dogara ne akan hanyar haɗin gwiwa, kuma ana buƙatar ƙarin cikakken bincike don bayyana dangantaka tsakanin crystallites da girman barbashi.Don bayyana wannan dangantaka, ta hanyar watsawa na lantarki microscopy (TEM) bincike hade tare da hanyar Rietveld da layin bayanan martaba na babban kididdiga na X-ray foda diffraction, da crystal microstructure sigogi (watau crystallites da barbashi size, siffar) an yi nazari a hankali. .XRPD) yanayin.Halayen tsarin yana da nufin tantance halayen anisotropic na nanocrystallites da aka samu da kuma tabbatar da yuwuwar nazarin bayanan martabar layi azaman ingantacciyar dabara don haɓaka kololuwa zuwa kewayon nanoscale na kayan (ferrite).An gano cewa girman girman girman girman kristal mai rarraba G(L) ya dogara da ƙarfi akan jagorar crystallographic.A cikin wannan aikin, mun nuna cewa ana buƙatar ƙarin dabaru don fitar da daidaitattun sigogi masu alaƙa da girman don kwatanta daidaitaccen tsari da halayen maganadisu na irin waɗannan samfuran foda.An kuma yi nazarin tsarin jujjuya maganadisu don fayyace alakar da ke tsakanin sifofin tsarin halittar jiki da halayyar maganadisu.
Rietveld bincike na X-ray foda diffraction (XRPD) bayanai ya nuna cewa girman crystallite tare da c-axis za a iya gyara ta dace zafi magani.Yana nuna musamman cewa kololuwar faɗaɗa da aka lura a cikin samfurinmu yana iya kasancewa saboda siffar crystallite anisotropic.Bugu da kari, daidaito tsakanin matsakaicin diamita da Rietveld yayi nazari da zane na Williamson-Hall (kumaa cikin Tebura S1) ya nuna cewa kristal sun kusan ba su da ƙarfi kuma babu nakasar tsari.Juyin Halitta na rarraba girman crystallite tare da kwatance daban-daban yana mai da hankalinmu akan girman barbashi da aka samu.Binciken ba mai sauƙi ba ne, saboda samfurin da aka samu ta hanyar sol-gel konewa ba tare da bata lokaci ba ya ƙunshi agglomerates na barbashi tare da tsari mai laushi6,9, ashirin da daya.Ana amfani da TEM don nazarin tsarin ciki na samfurin gwajin daki-daki.Ana ba da rahoton hotuna na filaye masu haske a cikin Hoto 3a-c (don cikakken bayanin bincike, da fatan za a koma zuwa sashe na 2 na ƙarin kayan).Samfurin ya ƙunshi barbashi tare da siffar ƙananan ƙananan.Platelet din suna haɗuwa tare don samar da juzu'ai masu girma da siffofi daban-daban.Domin kimanta girman rarraba platelets, an auna yanki na ɓangarorin 100 na kowane samfurin da hannu ta amfani da software na ImageJ.Diamita na da'irar da'irar daidai tare da yanki iri ɗaya kamar ƙimar ana dangana ga girman wakilcin kowane yanki da aka auna.Sakamakon samfurori SFOA, SFOB da SFOC an taƙaita su a cikin Hoto 3d-f, kuma an ba da rahoton matsakaicin ƙimar diamita.Ƙara yawan zafin jiki na aiki yana ƙara girman ɓangarorin da fadin rarraba su.Daga kwatancen tsakanin VTEM da VXRD (Table 1), ana iya ganin cewa a cikin yanayin SFOA da SFOB samfurori, matsakaicin adadin crystallites da kwayar halitta yana nuna yanayin polycrystalline na waɗannan lamellae.Sabanin haka, ƙarar barbashi na SFOC yana kama da matsakaicin ƙarar crystallite, yana nuna cewa yawancin lamellae lu'ulu'u ne guda ɗaya.Mun nuna cewa girman girman TEM da X-ray diffraction sun bambanta, saboda a cikin karshen, muna auna ma'auni mai mahimmanci (yana iya zama ƙasa da flake na al'ada): Bugu da ƙari, ƙananan kuskuren kuskuren waɗannan watsawa. za a ƙididdige yanki ta hanyar diffraction.
Hotunan TEM mai haske na (a) SFOA, (b) SFOB da (c) SFOC sun nuna cewa sun ƙunshi barbashi tare da siffar farantin karfe.Ana nuna madaidaicin girman rabon a cikin histogram na panel (df).
Kamar yadda muka kuma lura a cikin bincike na baya, crystallites a cikin samfurin foda na ainihi suna samar da tsarin polydispers.Tun da hanyar X-ray yana da matukar damuwa ga madaidaicin rarrabuwar kawuna, ana buƙatar cikakken bincike na bayanan diffraction foda don kwatanta kyawawan nanostructures.Anan, ana tattauna girman kristal ta hanyar halayyar girman girman girman girman girman girman girman girman G (L) 23, wanda za'a iya fassara shi azaman yuwuwar yuwuwar gano crystallites na siffa da girman da aka ɗauka, kuma nauyinsa yayi daidai da shi.Ƙarar, a cikin samfurin da aka bincika.Tare da sifar prismatic crystallite, za'a iya ƙididdige matsakaicin matsakaicin girma mai nauyi na crystallite (matsakaicin tsayin gefe a cikin [100], [110] da [001] kwatance).Saboda haka, mun zabi duk uku SFO samfurori tare da daban-daban barbashi masu girma dabam a cikin nau'i na anisotropic flakes (duba Reference 6) don kimanta tasiri na wannan hanya don samun daidai crystallite size rarraba nano-sikelin kayan.Don kimanta yanayin anisotropic na ferrite crystallites, an yi nazarin bayanan martaba na layi akan bayanan XRPD na kololuwar da aka zaɓa.Samfuran SFO da aka gwada ba su ƙunshi daidaitaccen tsari (tsarki) mafi girman tsari ba daga saiti ɗaya na jirage na crystal, don haka ba zai yuwu a raba gudummawar faɗaɗa layin da girma da murdiya ba.A lokaci guda kuma, haɓakar da aka lura na ɗimbin rarrabuwa ya fi dacewa saboda girman tasirin, kuma ana tabbatar da matsakaicin siffar crystallite ta hanyar nazarin layi da yawa.Hoto 4 yana kwatanta aikin rarraba girman girman kiristali mai nauyin girma G(L) tare da ƙayyadadden jagorar crystallographic.Halin nau'i na nau'i na girman girman crystallite shine rarrabawa na lognormal.Siffa ɗaya ta duk rabon girman da aka samu shine haɗin kai.A mafi yawan lokuta, ana iya danganta wannan rarraba zuwa wasu ƙayyadaddun tsarin samuwar barbashi.Bambanci tsakanin matsakaicin matsakaicin ƙididdiga na kololuwar da aka zaɓa da ƙimar da aka samo daga gyare-gyaren Rietveld yana cikin kewayon da aka yarda da shi (la'akari da cewa hanyoyin daidaita kayan aikin sun bambanta tsakanin waɗannan hanyoyin) kuma yana daidai da na daga daidaitattun jiragen sama ta hanyar. Debye Matsakaicin girman da aka samu ya yi daidai da ma'auni na Scherrer, kamar yadda aka nuna a cikin Tebura 2. Halin girman matsakaicin girman girman crystallite na dabaru daban-daban guda biyu yana da kama da juna, kuma karkacewar cikakken girman yana da ƙanƙanta.Kodayake ana iya samun rashin jituwa tare da Rietveld, alal misali, a cikin yanayin (110) tunani na SFOB, yana iya kasancewa yana da alaƙa da daidaitattun ƙayyadaddun bayanan baya a bangarorin biyu na tunanin da aka zaɓa a nesa na 1 digiri 2θ a kowace. hanya.Duk da haka, kyakkyawar yarjejeniya tsakanin fasahar biyu ta tabbatar da dacewa da hanyar.Daga nazarin faɗaɗa kololuwa, a bayyane yake cewa girman tare [001] yana da takamaiman dogaro ga hanyar haɗin gwiwa, wanda ya haifar da samuwar kristal mai walƙiya a cikin SFO6,21 wanda aka haɗa ta sol-gel.Wannan fasalin yana buɗe hanyar yin amfani da wannan hanyar don tsara nanocrystals tare da sifofin fifiko.Kamar yadda muka sani, hadadden tsarin crystal na SFO (kamar yadda aka nuna a cikin Hoto 1) shine ainihin halayen ferromagnetic na SFO12, don haka za'a iya daidaita siffar da girman halayen don inganta ƙirar samfurin don aikace-aikace (kamar dindindin. Magnet alaka).Mun nuna cewa ƙididdigar girman crystallite hanya ce mai ƙarfi don bayyana anisotropy na sifofin crystallite, kuma yana ƙara ƙarfafa sakamakon da aka samu a baya.
(a) SFOA, (b) SFOB, (c) SFOC zaɓaɓɓen tunani (100), (110), (004) girman girman girman girman girman girman girman G(L).
Don kimanta tasiri na hanya don samun daidaitaccen girman girman crystallite na kayan nano-foda da kuma amfani da shi zuwa nanostructures masu rikitarwa, kamar yadda aka nuna a cikin Hoto 5, mun tabbatar da cewa wannan hanya tana da tasiri a cikin kayan nanocomposite (masu daraja).Daidaiton shari'ar ya ƙunshi SrFe12O19/CoFe2O4 40/60 w/w %).Wadannan sakamakon sun kasance cikakke tare da nazarin Rietveld (duba taken Hoto na 5 don kwatantawa), kuma idan aka kwatanta da tsarin tsari guda ɗaya, SFO nanocrystals na iya haskaka wani nau'i mai kama da farantin karfe.Ana sa ran waɗannan sakamakon za su yi amfani da wannan binciken bayanan martaba na layi zuwa ƙarin hadaddun tsarin da nau'ikan kristal daban-daban za su iya mamayewa ba tare da rasa bayanai game da tsarin su ba.
Rarraba girman girman girman crystallite G (L) na zaɓaɓɓen tunani na SFO ((100), (004)) da CFO (111) a cikin nanocomposites;don kwatanta, daidaitattun ƙimar bincike na Rietveld shine 70 (7), 45 (6) da 67 (5) nm6.
Kamar yadda aka nuna a cikin Hoto na 2, ƙaddarar girman yankin maganadisu da madaidaicin ƙididdigewa na ƙarar jiki shine tushen bayanin irin wannan hadaddun tsarin da kuma fahimtar ma'amala da tsarin tsari tsakanin ƙwayoyin maganadisu.Kwanan nan, an yi nazarin halayen maganadisu na samfuran SFO daki-daki, tare da kulawa ta musamman ga tsarin jujjuyawar maganadisu, don yin nazarin abubuwan da ba za a iya jurewa ba na magnetic susceptibility (χirr) (Hoto S3 misali ne na SFOC) 6.Don samun zurfin fahimtar tsarin jujjuyawar maganadisu a cikin wannan tsarin nanosystem na tushen ferrite, mun yi ma'aunin shakatawa na maganadisu a cikin juzu'i (HREV) bayan jikewa a cikin wata hanyar da aka bayar.Yi la'akari da \ (M \ hagu (t \ dama) \ proptoSln hagu (t \ dama) \) (duba Hoto 6 da ƙarin bayani don ƙarin cikakkun bayanai) sannan sami ƙarar kunnawa (VACT).Tun da ana iya ayyana shi a matsayin ƙaramin ƙarar abu wanda za'a iya jujjuya shi tare a cikin wani lamari, wannan siga tana wakiltar ƙarar “magantaka” da ke cikin tsarin juyawa.Ƙimar VACT ɗin mu (duba Tebura S3) yayi daidai da yanki mai diamita na kusan 30 nm, wanda aka ayyana azaman madaidaicin diamita (DCOH), wanda ke bayyana babban iyakar jujjuyawar maganadisu na tsarin ta jujjuyawar daidaituwa.Ko da yake akwai babban bambanci a cikin jiki girma na barbashi (SFOA ne 10 sau girma fiye da SFOC), wadannan dabi'u ne quite akai da kuma kananan, yana nuna cewa magnetization juye inji na duk tsarin ya kasance iri ɗaya (daidai da abin da muke da'awar). shi ne tsarin yanki guda ɗaya) 24 .A ƙarshe, VACT yana da ƙarami ƙarami na jiki fiye da nazarin XRPD da TEM (VXRD da VTEM a cikin Tebur S3).Sabili da haka, zamu iya yanke shawarar cewa tsarin sauyawa ba kawai yana faruwa ta hanyar jujjuyawar daidaituwa ba.Lura cewa sakamakon da aka samu ta amfani da magnetometer daban-daban (Hoto S4) yana ba da ƙimar DCOH iri ɗaya iri ɗaya.Dangane da wannan, yana da matukar mahimmanci don ayyana mahimmancin diamita na yanki guda ɗaya (DC) don tantance tsarin juyawa mafi dacewa.Bisa ga binciken mu (duba ƙarin kayan aiki), za mu iya ɗauka cewa VACT da aka samu ya ƙunshi tsarin jujjuyawar da ba daidai ba, saboda DC (~ 0.8 µm) yana da nisa da DC (~ 0.8 µm) na barbashin mu, wato, samuwar ganuwar yanki ba a sami goyon baya mai ƙarfi kuma an sami saitin yanki guda ɗaya.Ana iya bayyana wannan sakamakon ta hanyar samuwar yanki na hulɗar25, 26. Muna ɗauka cewa crystallite guda ɗaya yana shiga cikin wani yanki na hulɗar, wanda ya shimfiɗa zuwa ɓangarorin haɗin gwiwa saboda ƙananan ƙananan ƙwayoyin waɗannan kayan27,28.Ko da yake hanyoyin X-ray suna kula da kyawawan ƙananan ƙananan yanki (microcrystals), ma'aunin shakatawa na maganadisu yana ba da shaida na hadaddun al'amura waɗanda zasu iya faruwa a cikin nanostructured SFOs.Sabili da haka, ta hanyar inganta girman nanometer na hatsi na SFO, yana yiwuwa a hana sauyawa zuwa tsarin juzu'i na yanki da yawa, ta haka yana riƙe da babban ƙarfin waɗannan kayan.
(a) Tsarin magnetization na lokaci-lokaci na SFOC wanda aka auna a filin juzu'i daban-daban na ƙimar HREV bayan jikewa a-5 T da 300 K (wanda aka nuna kusa da bayanan gwaji) (maganin haɓakawa yana daidaitawa gwargwadon nauyin samfurin);don tsabta, Wurin yana nuna bayanan gwaji na filin 0.65 T (da'irar baƙar fata), wanda ke da mafi kyawun dacewa (layin ja) (magnetization an daidaita shi zuwa ƙimar farko M0 = M (t0));(b) madaidaicin magnetic danko (S) shine juzu'in SFOC A aikin filin (layin jagora ne ga ido);(c) tsarin tsarin kunnawa tare da cikakkun bayanan ma'auni na jiki / maganadisu.
Gabaɗaya magana, jujjuyawar maganadisu na iya faruwa ta hanyar jerin matakai na gida, irin su bangon bangon yanki, yaɗawa, da fiɗa da kwancewa.A cikin yanayin barbashi na ferrite guda ɗaya, tsarin kunnawa yana tsaka-tsakin tsakiya kuma ana haifar da shi ta hanyar canjin maganadisu karami fiye da jimlar juyar da maganadisu (kamar yadda aka nuna a hoto 6c)29.
Rata tsakanin mahimmancin maganadisu da diamita na jiki yana nuna cewa yanayin rashin daidaituwa shine yanayin juzu'i na jujjuyawar yanki, wanda zai iya zama saboda rashin daidaituwa na kayan abu da rashin daidaituwa na saman, wanda ya zama mai alaƙa lokacin da girman barbashi ya karu 25, yana haifar da karkacewa daga. yanayin magnetization uniform.
Sabili da haka, zamu iya yanke shawarar cewa a cikin wannan tsarin, tsarin juyawa na magnetization yana da matukar rikitarwa, kuma ƙoƙarin rage girman a cikin ma'auni na nanometer yana taka muhimmiyar rawa a cikin hulɗar tsakanin microstructure na ferrite da magnetism..
Fahimtar hadadden alaƙa tsakanin tsari, tsari da maganadisu shine tushen ƙira da haɓaka aikace-aikacen gaba.Binciken bayanan martaba na layin XRPD da aka zaɓa na SrFe12O19 ya tabbatar da siffar anisotropic na nanocrystals da aka samu ta hanyar haɗin gwiwarmu.Haɗe tare da bincike na TEM, an tabbatar da yanayin polycrystalline na wannan ƙwayar, kuma daga baya an tabbatar da cewa girman SFO da aka bincika a cikin wannan aikin ya kasance ƙasa da mahimmancin yanki guda ɗaya mai mahimmanci, duk da shaidar girma na crystallite.A kan wannan, muna ba da shawarar wani tsari na maganadisu wanda ba zai iya jurewa ba dangane da samuwar yankin hulɗa wanda ya ƙunshi crystallites masu haɗin gwiwa.Sakamakonmu yana tabbatar da kusancin kusanci tsakanin kwayar halittar kwayar halitta, tsarin crystal da girman crystallite wanda ke wanzu a matakin nanometer.Wannan binciken yana da nufin fayyace tsarin jujjuyawar maganadisu na kayan maganadisu masu ƙarfi na nanostructured da ƙayyadaddun halayen sifofin microstructure a sakamakon halayen maganadisu.
An haɗa samfurori ta amfani da citric acid a matsayin wakili na chelating / man fetur bisa ga hanyar sol-gel ba tare da bata lokaci ba, wanda aka ruwaito a cikin Reference 6. An inganta yanayin haɗin gwiwar don samun nau'o'in nau'i daban-daban guda uku (SFOA, SFOB, SFOC), waɗanda suka kasance. ana samun su ta hanyar jiyya da suka dace a yanayin zafi (1000, 900, da 800 ° C, bi da bi).Tebura S1 yana taƙaita kaddarorin maganadisu kuma ya gano cewa sun yi kama da juna.Nanocomposite SrFe12O19/CoFe2O4 40/60 w/w% an kuma shirya shi ta irin wannan hanya.
An auna tsarin rarrabuwar kawuna ta amfani da radiation CuKα (λ = 1.5418 Å) akan Bruker D8 foda diffractometer, kuma an saita faɗin tsaga mai ganowa zuwa 0.2 mm.Yi amfani da ma'aunin VANTEC don tattara bayanai a cikin kewayon 2θ na 10-140°.An kiyaye zafin jiki yayin rikodin bayanai a 23 ± 1 °C.Ana auna ma'auni ta hanyar fasaha na mataki-da-scan, kuma tsayin mataki na duk samfuran gwaji shine 0.013 ° (2theta);Matsakaicin ƙimar ƙimar nisan auna shine-2.5 da + 2.5° (2theta).Ga kowane kololuwa, ana ƙididdige jimillar ƙididdiga 106, yayin da wutsiya akwai kusan 3000.An zaɓi kololuwar gwaji da yawa (raɓawa ko ɓangarori daban-daban) don ƙarin bincike na lokaci guda: (100), (110) da (004), waɗanda suka faru a kusurwar Bragg kusa da kusurwar Bragg na layin rajista na SFO.An gyara ƙarfin gwaji don ma'aunin polarization Lorentz, kuma an cire bangon tare da canjin layin da aka ɗauka.An yi amfani da ma'auni na NIST LaB6 (NIST 660b) don daidaita kayan aiki da faɗaɗawa.Yi amfani da LWL (Louer-Weigel-Louboutin) Hanyar rarrabuwar kawuna 30,31 don samun tsattsauran layukan rarrabawa.Ana aiwatar da wannan hanyar a cikin shirin nazarin bayanan martaba PROFIT-software32.Daga dacewa da ma'aunin ma'aunin ƙarfin samfurin da ma'auni tare da aikin ƙirƙira Voigt, an fitar da daidaitaccen kwane-kwane f(x) daidai.Girman aikin rarraba G (L) an ƙayyade shi daga f(x) ta bin hanyar da aka gabatar a cikin Reference 23. Don ƙarin cikakkun bayanai, da fatan za a duba ƙarin kayan.A matsayin ƙari ga ƙididdigar bayanin martaba na layi, ana amfani da shirin FULLPROF don yin nazarin Rietveld akan bayanan XRPD (ana iya samun cikakkun bayanai a Maltoni et al. 6).A taƙaice, a cikin ƙirar Rietveld, an kwatanta kololuwar ɓarna ta hanyar aikin Thompson-Cox-Hastings na pseudo Voigt da aka gyara.An yi gyaran bayanan LeBail akan ma'aunin NIST LaB6 660b don kwatanta gudunmawar kayan aikin don faɗaɗa kololuwa.Dangane da FWHM da aka ƙididdige (cikakken nisa a rabin ƙarfin kololuwa), ana iya amfani da ma'auni na Debye-Scherrer don ƙididdige matsakaicin girman ma'aunin nauyi na yanki mai rarraba crystalline mai daidaituwa:
Inda λ shine tsawon radiyon X-ray, K shine sifar sifar (0.8-1.2, yawanci daidai da 0.9), kuma θ shine kusurwar Bragg.Wannan ya shafi: tunanin da aka zaɓa, daidaitattun saitin jiragen sama da dukan tsarin (10-90 °).
Bugu da kari, an yi amfani da na'urar microscope Philips CM200 da ke aiki a 200 kV kuma sanye take da filament na LaB6 don nazarin TEM don samun bayanai game da ilimin halittar jiki da kuma rarraba girman.
Ana yin ma'aunin shakatawa na Magnetization ta na'urori daban-daban guda biyu: Tsarin Ma'aunin Ma'auni na Jiki (PPMS) daga Ƙwararren Ƙirƙirar Samfuran Magnetometer (VSM), sanye take da 9 T superconducting magnet, da MicroSense Model 10 VSM tare da electromagnet.Filin shine 2 T, samfurin ya cika a cikin filin (μ0HMAX: -5 T da 2 T, bi da bi ga kowane kayan aiki), sa'an nan kuma ana amfani da filin baya (HREV) don kawo samfurin a cikin wurin sauyawa (kusa da HC). ), sa'an nan kuma Ana yin rikodin lalatawar maganadisu azaman aikin lokaci sama da mintuna 60.Ana yin ma'auni a 300 K. Ana ƙididdige ƙarar kunnawa daidai bisa ga ma'aunin ma'auni da aka kwatanta a cikin ƙarin kayan.
Muscas, G., Yaacub, N. & Peddis, D. Tashin hankali na Magnetic a cikin kayan nanostructured.A cikin sabon Magnetic nanostructure 127-163 (Elsevier, 2018).doi.org/10.1016/B978-0-12-813594-5.00004-7.
Mathieu, R. da Nordblad, P. Halayen maganadisu na gama gari.A cikin sabon yanayin maganadisu na nanoparticle, shafi na 65-84 (2021).doi.org/10.1007/978-3-030-60473-8_3.
Dormann, JL, Fiorani, D. & Tronc, E. Magnetic shakatawa a cikin lafiya barbashi tsarin.Ci gaba a Kimiyyar Kimiyya, shafi na 283-494 (2007).doi.org/10.1002/9780470141571.ch4.
Sellmyer, DJ, da dai sauransu Sabon tsari da kimiyyar lissafi na nanomagnets (gayyace).J. Aikace-aikacen Physics 117, 172 (2015).
de Julian Fernandez, C. da dai sauransu. Thematic review: ci gaba da kuma bege na wuya hexaperrite m maganadisu aikace-aikace.J. Physics.D. Nemi don Physics (2020).
Maltoni, P. da dai sauransu Ta hanyar inganta haɓakawa da kaddarorin maganadisu na SrFe12O19 nanocrystals, ana amfani da nanocomposites na magnetic dual azaman maganadisu na dindindin.J. Physics.D. Nemi Physics 54, 124004 (2021).
Saura-Múzquiz, M. da sauransu. Bayyana alaƙar da ke tsakanin nanoparticle ilimin halittar jiki, tsarin nukiliya/magnetic da kaddarorin maganadisu na sintered SrFe12O19 maganadiso.Nano 12, 9481-9494 (2020).
Petrecca, M. da dai sauransu. Inganta da Magnetic Properties na wuya da taushi kayan don samar da musayar spring m maganadiso.J. Physics.D. Nemi Physics 54, 134003 (2021).
Maltoni, P. da dai sauransu. Daidaita kaddarorin maganadisu na nanostructures SrFe12O19/CoFe2O4 mai taushi ta hanyar abun da ke ciki/ hadewar lokaci.J. Physics.Chemistry C 125, 5927-5936 (2021).
Maltoni, P. da dai sauransu. Bincika haɗin gwiwar maganadisu da maganadisu na SrFe12O19/Co1-xZnxFe2O4 nanocomposites.J. Mag.Mag.almajiri.535, 168095 (2021).
Pullar.Gyara.almajiri.kimiyya.57, 1191-1334 (2012).
Momma, K. & Izumi, F. VESTA: Tsarin gani na 3D don nazarin lantarki da tsarin.J. Tsarin da aka Aiwatar da Crystallography 41, 653-658 (2008).
Peddis, D., Jönsson, PE, Laureti, S. & Varvaro, G. Magnetic hulda.Iyakoki a Nanoscience, shafi na 129-188 (2014).doi.org/10.1016/B978-0-08-098353-0.00004-X.
Li, Q. da dai sauransu A daidaituwa tsakanin girman / tsarin yanki na sosai crystalline Fe3O4 nanoparticles da Magnetic Properties.kimiyya.Wakili 7, 9894 (2017).
Coey, JMD Magnetic da Magnetic kayan.(Jami'ar Jami'ar Cambridge, 2001).doi.org/10.1017/CBO9780511845000.
Lauretti, S. et al.Haɗin kai na Magnetic a cikin abubuwan nanoporous masu rufin silica na CoFe2O4 nanoparticles tare da anisotropy magnetic cubic.Nanotechnology 21, 315701 (2010).
O'Grady, K. & Laidler, H. Iyakance na la'akari da rikodin maganadisu-kafofin watsa labarai.J. Mag.Mag.almajiri.200, 616-633 (1999).
Lavorato, GC da dai sauransu. Ana haɓaka hulɗar maganadisu da shingen makamashi a cikin core/harsashi dual Magnetic nanoparticles.J. Physics.Chemistry C 119, 15755-15762 (2015).
Peddis, D., Cannas, C., Musinu, A. & Piccaluga, G. Magnetic Properties na nanoparticles: fiye da rinjayar barbashi size.Chemistry Euro daya.J. 15, 7822-7829 (2009).
Eikeland, AZ, Stingaciu, M., Mamakhel, AH, Saura-Múzquiz, M. & Christensen, M. Haɓaka kaddarorin maganadisu ta hanyar sarrafa yanayin halittar SrFe12O19 nanocrystals.kimiyya.Wakili 8, 7325 (2018).
Schneider, C., Rasband, W. da Eliceiri, K. NIH Hoton zuwa ImageJ: 25 shekaru na nazarin hoto.A. Nat.Hanyar 9, 676-682 (2012).
Le Bail, A. & Louër, D. Smoothness da ingancin rarraba girman crystallite a cikin nazarin bayanan martaba na X-ray.J. Tsarin da aka Aiwatar da Crystallography 11, 50-55 (1978).
Gonzalez, JM, da dai sauransu Magnetic danko da microstructure: barbashi size dogara da kunnawa girma.J. Lissafin Lissafi 79, 5955 (1996).
Vavaro, G., Agostinelli, E., Testa, AM, Peddis, D. da Laureti, S. a cikin ultra-high density Magnetic rikodin.(Jenny Stanford Press, 2016).doi.org/10.1201/b20044.
Hu, G., Thomson, T., Rettner, CT, Raoux, S. & Terris, BD Co∕Pd nanostructures da kuma fim maganadiso koma baya.J. Application Physics 97, 10J702 (2005).
Khlopkov, K., Gutfleisch, O., Hinz, D., Müller, K.-H.& Schultz, L. Juyin Halittu na yankin hulɗa a cikin maganadisun Nd2Fe14B mai laushi mai laushi.J. Application Physics 102, 023912 (2007).
Mohapatra, J., Xing, M., Elkins, J., Beatty, J. & Liu, JP Size-dogara Magnetic hardening a cikin CoFe2O4 nanoparticles: sakamakon surface karkatar karkatarwa.J. Physics.D. Nemi Physics 53, 504004 (2020).