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Sisebenzisa amakhukhi ukuthuthukisa ulwazi lwakho.Ngokuqhubeka nokuphequlula leli sayithi, uyavumelana nokusebenzisa kwethu amakhukhi.Ulwazi olwengeziwe.
Uma kubikwa ngengozi yomgwaqo enye yezimoto isuka endaweni yesigameko, ama-laboratories ahlola amacala avame ukujutshwa ukubuyisa ubufakazi.
Ubufakazi obusalele buhlanganisa ingilazi ephukile, izibani zangaphambili eziphukile, amalambu angemuva, noma obhampa, kanye nama-skid marks nezinsalela zikapende.Uma imoto ishayisana nento noma umuntu, upende kungenzeka udlulise ngendlela yamabala noma ama-chips.
Upende wezimoto ngokuvamile uyingxube eyinkimbinkimbi yezithako ezihlukene ezisetshenziswa ezingqimbeni eziningi.Nakuba lobu bunzima buhlanganisa ukuhlaziya, buphinde bunikeze ingcebo yolwazi olungase lubaluleke kakhulu ekuhlonzeni imoto.
I-Raman microscopy kanye ne-Fourier transform infrared (FTIR) kungamanye amasu ayinhloko angasetshenziswa ukuxazulula izinkinga ezinjalo futhi kube lula ukuhlaziya okungonakali kwezendlalelo ezithile esakhiweni sokumboza sisonke.
Ukuhlaziywa kwe-chip kapende kuqala ngedatha ye-spectral engaqhathaniswa ngokuqondile namasampuli okulawula noma asetshenziswe ngokuhambisana nesizindalwazi ukuze kunqunywe ukwakheka, imodeli, nonyaka wemoto.
IRoyal Canadian Mounted Police (RCMP) igcina isizindalwazi esisodwa esinjalo, isizindalwazi sePaint Data Query (PDQ).Amalabhorethri abambe iqhaza angafinyelelwa nganoma yisiphi isikhathi ukuze asize ekulondolozeni nasekunwebiseni imininingwane.
Lesi sihloko sigxile esinyathelweni sokuqala senqubo yokuhlaziya: ukuqoqa idatha ye-spectral kuma-chip chips kusetshenziswa i-FTIR ne-Raman microscopy.
Idatha ye-FTIR yaqoqwa kusetshenziswa isibonakhulu se-Thermo Scientific™ Nicolet™ RaptIR™ FTIR;idatha ephelele ye-Raman yaqoqwa kusetshenziswa isibonakhulu se-Thermo Scientific™ DXR3xi Raman.Ama-chips kapende athathwe ezingxenyeni ezilimele zemoto: elinye likhishwe kuphaneli lomnyango, elinye kubhampa.
Indlela evamile yokunamathisela izibonelo ze-cross-sectional ukuziphonsa nge-epoxy, kodwa uma i-resin ingena kusampula, imiphumela yokuhlaziywa ingase ithinteke.Ukuvimbela lokhu, izingcezu zikapende zazibekwe phakathi kwamashidi amabili e-poly(tetrafluoroethylene) (PTFE) esigabeni esiphambanayo.
Ngaphambi kokuhlaziywa, ingxenye ephambene yekhiphu kapende yahlukaniswa mathupha ne-PTFE futhi i-chip yabekwa efasiteleni le-barium fluoride (BaF2).Imephu ye-FTIR yenziwe ngemodi yokudlulisa kusetshenziswa imbobo engu-10 x 10 µm2, umgomo olungiselelwe ongu-15x kanye ne-condenser, kanye nephimbo elingu-5 µm.
Amasampula afanayo asetshenziswe ekuhlaziyeni kwe-Raman ukuze alingane, nakuba ingxenye encane yewindi ye-BaF2 ingadingeki.Kuyaphawuleka ukuthi i-BaF2 inenani eliphakeme le-Raman ku-242 cm-1, elingabonakala njengenani elibuthakathaka kwezinye izibukeli.Isignali akufanele ihlotshaniswe nama-flakes opende.
Thola izithombe ze-Raman usebenzisa osayizi bephikseli besithombe abangu-2 µm no-3 µm.Ukuhlaziywa kwe-Spectral kwenziwa eziqongweni zengxenye eyinhloko futhi inqubo yokuhlonza yasizwa ukusetshenziswa kwamasu anjengosesho lwezingxenye eziningi uma kuqhathaniswa nemitapo yolwazi etholakala ngokuthengisa.
Ilayisi.1. Umdwebo wesampula evamile kapende wezimoto ezinezendlalelo ezine (kwesokunxele).I-mosaic yevidiyo ehlukanisayo yezingxenye zopende ezithathwe emnyango wemoto (kwesokudla).Ikhredithi Yesithombe: I-Thermo Fisher Scientific - Materials and Structural Analysis
Nakuba inani lezendlalelo zamakhekheba opende kusampula lingahluka, amasampuli ngokuvamile ahlanganisa cishe izendlalelo ezine (Umfanekiso 1).Isendlalelo esisetshenziswa ngokuqondile ku-substrate yensimbi ungqimba lwe-electrophoretic primer (ecishe ibe ngu-17-25 µm ubukhulu) olusebenza ukuvikela insimbi endaweni ezungezile futhi lusebenza njengendawo ekhwezayo yezendlalelo ezilandelayo zopende.
Isendlalelo esilandelayo siyi-primer eyengeziwe, i-putty (cishe ama-microns angu-30-35 ubukhulu) ukuze unikeze indawo ebushelelezi yochungechunge olulandelayo lwezendlalelo zepende.Bese kuza i-base coat noma i-base coat (cishe u-10-20 µm ubukhulu) ehlanganisa i-pigment kapende wesisekelo.Isendlalelo sokugcina siwugqinsi oluvikelayo olusobala (cishe ugqinsi lwama-microns angu-30-50) olunikeza nokuqeda okucwebezelayo.
Enye yezinkinga eziyinhloko ngokuhlaziywa kokulandelela upende ukuthi akuzona zonke izingqimba zikapende emotweni yasekuqaleni ezikhona njengama-chips opende kanye namabala.Ngaphezu kwalokho, amasampula avela ezifundeni ezahlukene angase abe nokuqanjwa okuhlukile.Isibonelo, ama-chips opende kubhampa angase aqukathe impahla enkulu nopende.
Isithombe esibonakalayo se-cross-sectional chip sikapende siboniswa kuMfanekiso 1. Izendlalelo ezine ziyabonakala esithombeni esibonakalayo, esihambisana nezendlalelo ezine ezikhonjwe ngokuhlaziywa kwe-infrared.
Ngemva kokwenza imephu yonke ingxenye ephambanayo, izendlalelo ngazinye zihlonzwe kusetshenziswa izithombe ze-FTIR zezindawo eziphakeme ezihlukahlukene.I-spectra emele kanye nezithombe ze-FTIR ezihambisana nazo zezendlalelo ezine ziboniswa ku-Fig.2. Isendlalelo sokuqala sihambisana nombala we-acrylic obala ohlanganisa i-polyurethane, i-melamine (i-peak ku-815 cm-1) ne-styrene.
Isendlalelo sesibili, ungqimba oluyisisekelo (umbala) kanye nongqimba olucacile lufana namakhemikhali futhi luhlanganisa i-acrylic, i-melamine ne-styrene.
Nakuba zifana futhi azikho iziqongo ze-pigment ezithile ezihlonziwe, i-spectra isabonisa umehluko, ikakhulukazi mayelana nokuqina okuphezulu.Uhlaka 1 lubonisa iziqongo eziqinile ku-1700 cm-1 (polyurethane), 1490 cm-1, 1095 cm-1 (CO) kanye no-762 cm-1.
Ukuqina okuphezulu ku-spectrum ye-layer 2 ukwanda ku-2959 cm-1 (methyl), 1303 cm-1, 1241 cm-1 (ether), 1077 cm-1 (ether) kanye ne-731 cm-1.I-spectrum yongqimba olungaphezulu ihambisana ne-spectrum yelabhulali ye-alkyd resin esekelwe ku-isophthalic acid.
Ijazi lokugcina le-e-coat primer yi-epoxy futhi ngokunokwenzeka i-polyurethane.Ekugcineni, imiphumela yayihambisana naleyo evame ukutholakala kumapende ezimoto.
Ukuhlaziywa kwezingxenye ezihlukene kusendlalelo ngasinye kwenziwa kusetshenziswa imitapo yolwazi ye-FTIR etholakalayo ukuze ihwebe, hhayi imininingo egciniwe yopende wezimoto, ngakho nakuba okufanayo kumelela, kungase kungabi ngokuphelele.
Ukusebenzisa isizindalwazi esiklanyelwe lolu hlobo lokuhlaziya kuzokwandisa ukubonakala ngisho nokwakheka, imodeli nonyaka wemoto.
Umfanekiso 2. I-spectra emele i-FTIR yezendlalelo ezine ezikhonjiwe engxenyeni ephambanayo kapende womnyango wemoto okhishiwe.Izithombe ze-infrared zikhiqizwa ezindaweni eziphakeme kakhulu ezihlobene nezendlalelo ngazinye futhi zibekwe phezulu esithombeni sevidiyo.Izindawo ezibomvu zibonisa indawo yezendlalelo ngazinye.Kusetshenziswa indawo engu-10 x 10 µm2 kanye nosayizi wesinyathelo esingu-5 µm, isithombe se-infrared sivala indawo engu-370 x 140 µm2.Ikhredithi Yesithombe: I-Thermo Fisher Scientific - Materials and Structural Analysis
Emkhiwaneni.3 ikhombisa isithombe sevidiyo sesigaba esiphambanayo samashidi kapende kabhampa, okungenani izendlalelo ezintathu zibonakala kahle.
Izithombe ze-infrared cross-sectional ziqinisekisa ukuba khona kwezingqimba ezintathu ezihlukene (Fig. 4).Ungqimba lwangaphandle luyijazi elicacile, okungenzeka ukuthi i-polyurethane ne-acrylic, elalingaguquguquki uma liqhathaniswa ne-spectra yejazi elicacile emitatsheni yolwazi yezohwebo.
Nakuba i-spectrum yesisekelo (umbala) yokugqoka ifana kakhulu nesembozo esicacile, isahluke ngokwanele ukuze ihlukaniswe nongqimba lwangaphandle.Kunomehluko omkhulu ekuqineni okuhlobene kweziqongo.
Isendlalelo sesithathu singaba yi-bumper material ngokwayo, ehlanganisa i-polypropylene ne-talc.I-Talc ingasetshenziswa njengesigcwalisi esiqinisayo se-polypropylene ukuthuthukisa izakhiwo zesakhiwo.
Womabili amajazi angaphandle ayehambisana nalawo asetshenziswa kupende wezimoto, kodwa azikho iziqongo ze-pigment ezithile ezikhonjwe ku-primer coat.
Ilayisi.3. I-mosaic yevidiyo yengxenye ephambanayo yama-chips opende athathwe kubhampa wemoto.Ikhredithi yesithombe: Thermo Fisher Scientific - Materials and Structural Analysis
Ilayisi.4. I-spectra emele i-FTIR yezendlalelo ezintathu ezikhonjiwe esigabeni esiphambanayo samashidi kapende kubhampa.Izithombe ze-infrared zikhiqizwa ezindaweni eziphakeme kakhulu ezihlobene nezendlalelo ngazinye futhi zibekwe phezulu esithombeni sevidiyo.Izindawo ezibomvu zibonisa indawo yezendlalelo ngazinye.Kusetshenziswa indawo engu-10 x 10 µm2 kanye nosayizi wesinyathelo esingu-5 µm, isithombe se-infrared sivala indawo engu-535 x 360 µm2.Ikhredithi Yesithombe: I-Thermo Fisher Scientific - Materials and Structural Analysis
I-Raman imaging microscopy isetshenziselwa ukuhlaziya uchungechunge lwezigaba eziphambene ukuze kutholwe ulwazi olwengeziwe mayelana nesampula.Kodwa-ke, ukuhlaziya kwe-Raman kuyinkimbinkimbi yi-fluorescence ekhishwa isampula.Imithombo ye-laser eminingana ehlukene (455 nm, 532 nm kanye ne-785 nm) yahlolwa ukuze kuhlolwe ibhalansi phakathi kokuqina kwe-fluorescence kanye nokuqina kwesignali ye-Raman.
Ukuze kuhlaziywe ama-chips opende eminyango, imiphumela engcono kakhulu itholakala nge-laser ene-wavelength ye-455 nm;nakuba i-fluorescence isekhona, ukulungiswa kwesisekelo kungasetshenziswa ukulwa nakho.Kodwa-ke, le ndlela ayizange iphumelele kuma-epoxy layers ngoba i-fluorescence yayinomkhawulo kakhulu futhi okokusebenza kwakusengozini yokulimala kwe-laser.
Nakuba amanye ama-laser engcono kunamanye, ayikho i-laser elungele ukuhlaziywa kwe-epoxy.Ukuhlaziywa kwe-Raman okunqamula izingxenye zamashiphu opende kubhampa kusetshenziswa i-laser engu-532 nm.Umnikelo we-fluorescence usekhona, kodwa ususwe ngokulungiswa okuyisisekelo.
Ilayisi.5. I-spectra emele i-Raman yezendlalelo ezintathu zokuqala zesampula ye-chip yomnyango wemoto (kwesokudla).Isendlalelo sesine (i-epoxy) silahlekile ngesikhathi sokwenziwa kwesampula.I-spectra yalungiswa isisekelo ukuze kususwe umphumela we-fluorescence futhi yaqoqwa kusetshenziswa i-laser engu-455 nm.Indawo engu-116 x 100 µm2 iboniswe kusetshenziswa usayizi wephikseli ongu-2 µm.I-mosaic yevidiyo ehlukanisayo (phezulu kwesokunxele).Isithombe se-multidimensional Raman Curve Resolution (MCR) esinezigaba (phansi kwesokunxele).Ikhredithi Yesithombe: I-Thermo Fisher Scientific - Materials and Structural Analysis
Ukuhlaziywa kwe-Raman kwengxenye yesiphambano socezu lwepende yomnyango wemoto kuboniswe kuMfanekiso 5;lesi sampula asibonisi isendlalelo se-epoxy ngoba silahlekile ngesikhathi sokulungiswa.Kodwa-ke, njengoba ukuhlaziywa kwe-Raman kwesendlalelo se-epoxy kutholakale kuyinkinga, lokhu akuzange kubhekwe njengenkinga.
Ubukhona be-styrene bubusa ku-spectrum ye-Raman yongqimba 1, kuyilapho isiqongo se-carbonyl sishubile kakhulu kunesibukeli se-IR.Uma kuqhathaniswa ne-FTIR, ukuhlaziya kwe-Raman kukhombisa umehluko omkhulu ku-spectra yesendlalelo sokuqala nesesibili.
Umeshi we-Raman oseduze kakhulu nejazi lesisekelo yi-perylene;nakuba kungekona ukufana ncamashi, okuphuma ku-perylene kwaziwa ukuthi kusetshenziswe kumbala kupende wezimoto, ngakho-ke kungase kumele umbala kungqimba lombala.
I-spectra engaphezulu yayihambisana ne-isophthalic alkyd resins, nokho futhi ithole ukuba khona kwe-titanium dioxide (TiO2, rutile) kumasampuli, okwakunzima ngezinye izikhathi ukuyibona nge-FTIR, kuye ngokuthi i-spectral cutoff.
Ilayisi.6. Omele i-Raman spectrum yesampula yamashiphu opende kubhampa (kwesokudla).I-spectra yalungiswa isisekelo ukuze kususwe umphumela we-fluorescence futhi yaqoqwa kusetshenziswa i-laser engu-532 nm.Indawo engu-195 x 420 µm2 iboniswe kusetshenziswa usayizi wephikseli ongu-3 µm.I-mosaic yevidiyo ehlukanisayo (phezulu kwesokunxele).Isithombe se-Raman MCR sengxenye ephambene (phansi kwesokunxele).Ikhredithi yesithombe: Thermo Fisher Scientific - Materials and Structural Analysis
Emkhiwaneni.6 ikhombisa imiphumela ye-Raman yokusakazwa kwengxenye ephambanayo yama-chips opende kubhampa.Kutholwe isendlalelo esengeziwe (ungqimba 3) esingazange sitholwe yi-FTIR.
Eduze kwesendlalelo sangaphandle i-copolymer ye-styrene, i-ethylene ne-butadiene, kodwa kukhona nobufakazi bokuba khona kwengxenye eyengeziwe engaziwa, njengoba kufakazelwa i-carbonyl peak encane engaqondakali.
I-spectrum ye-base coat ingase ibonise ukubunjwa kwe-pigment, njengoba i-spectrum ihambelana ngezinga elithile nenhlanganisela ye-phthalocyanine esetshenziswa njenge-pigment.
Isendlalelo esingaziwa ngaphambilini sizacile kakhulu (5 µm) futhi ngokwengxenye sakhiwe ikhabhoni ne-rutile.Ngenxa yokuqina kwalesi singqimba kanye neqiniso lokuthi i-TiO2 nekhabhoni kunzima ukukubona nge-FTIR, akumangazi ukuthi akuzange kubonwe ngokuhlaziywa kwe-IR.
Ngokwemiphumela ye-FT-IR, isendlalelo sesine (impahla enkulu) ikhonjwe njenge-polypropylene, kodwa ukuhlaziya kwe-Raman kuphinde kwabonisa ukuba khona kwekhabhoni ethile.Nakuba ukuba khona kwe-talc okuphawulwe ku-FITR kungenakukhishwa ngaphandle, ukuhlonza okunembile ngeke kwenziwe ngoba isiqongo esihambisanayo se-Raman sincane kakhulu.
Opende bezimoto bayinhlanganisela eyinkimbinkimbi yezithako, futhi nakuba lokhu kunganikeza ulwazi oluningi lokuhlonza, kuphinde kwenza ukuhlaziya kube inselele enkulu.Izimpawu ze-chip zikapende zingatholwa ngempumelelo kusetshenziswa isibonakhulu se-Nicolet RaptIR FTIR.
I-FTIR iwuhlelo lokuhlaziya olungacekeli phansi oluhlinzeka ngolwazi oluwusizo mayelana nezendlalelo ezihlukahlukene nezingxenye zopende wezimoto.
Lesi sihloko sidingida ukuhlaziywa kwe-spectroscopic kwezingqimba zopende, kodwa ukuhlaziya okuphelele kakhulu kwemiphumela, noma ngokuqhathanisa okuqondile nezimoto ezisolwayo noma ngokusebenzisa imininingwane egciniwe ye-spectral ezinikele, kunganikeza ulwazi olunembe kakhudlwana ukufanisa ubufakazi nomthombo wakho.