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Isu tinoshandisa makuki kuvandudza ruzivo rwako.Nekuramba uchitsvaga saiti ino, unobvuma kushandisa kwedu makuki.Mamwe mashoko.
Kana tsaona yemumugwagwa ichitaurwa uye imwe yemotokari ichibva panzvimbo, marabhoritari ezvekuferefeta anowanzo kupihwa basa rekutora humbowo.
Humbowo huchasara hunosanganisira magirazi akatyoka, marambi emberi akatyoka, maraiti ekumashure, kana mabhampa, pamwe nemakidhi ekutsvedza nependi.Kana mota yadhumhana nechinhu kana munhu, pendi yacho inogona kufambisa nenzira yemavara kana machipisi.
Pendi yemotokari inowanzova musanganiswa wakaoma wezvinhu zvakasiyana-siyana zvinoshandiswa mumatanho akawanda.Nepo kuomarara uku kuchinetsa kuongorora, kunopawo hupfumi hweruzivo rwakakosha rwekuziva mota.
Raman microscopy uye Fourier anoshandura infrared (FTIR) mamwe ematekiniki makuru anogona kushandiswa kugadzirisa matambudziko akadai uye kufambisa kusingaparadze kuongororwa kwematanho chaiwo mune yakazara coating chimiro.
Paint chip analysis inotanga ne spectral data inogona kufananidzwa zvakananga nekutonga samples kana kushandiswa pamwe chete nedhatabhesi kuti ione kugadzira, modhi, uye gore remotokari.
Iyo Royal Canadian Mounted Police (RCMP) inochengetedza imwe dhatabhesi, iyo Paint Data Query (PDQ) dhatabhesi.Kutora chikamu forensic marabhoritari anogona kuwanikwa chero nguva kubatsira kuchengetedza uye kuwedzera dhatabhesi.
Ichi chinyorwa chinotarisa padanho rekutanga mukugadzirisa maitiro: kuunganidza spectral data kubva pendi machipisi uchishandisa FTIR uye Raman microscopy.
FTIR data yakaunganidzwa pachishandiswa Thermo Scientific™ Nicolet™ RaptIR™ FTIR maikorosikopu;data rakazara reRaman rakaunganidzwa pachishandiswa Thermo Scientific™ DXR3xi Raman microscope.Pendi machipisi akatorwa kubva pakakuvadzwa zvikamu zvemota: imwe yakaputswa kubva pamusuwo wepaneru, imwe kubva kune bumper.
Iyo yakajairwa nzira yekubatanidza muchinjika-sectional specimens ndeyekukanda iwo epoxy, asi kana resin ikapinda mumuenzaniso, mhedzisiro yekuongorora inogona kukanganiswa.Kudzivirira izvi, zvidimbu zvependi zvakaiswa pakati pemapepa maviri epoly(tetrafluoroethylene) (PTFE) pamuchinjikwa.
Isati yaongororwa, chikamu chemuchinjikwa chependi chip chakaparadzaniswa nemaoko kubva kuPTFE uye chip chakaiswa pahwindo rebarium fluoride (BaF2).Mamepu eFTIR akaitwa nenzira yekufambisa uchishandisa 10 x 10 µm2 aperture, chinangwa chakagadziridzwa 15x uye condenser, uye 5 µm pitch.
Iwo masampula mamwechete akashandiswa pakuongorora kweRaman kuti awirirane, kunyangwe iyo yakaonda yeBaF2 hwindo muchinjiko chikamu haidiwi.Zvakakosha kuziva kuti BaF2 ine Raman peak pa 242 cm-1, iyo inogona kuonekwa seyepamusoro isina simba mune imwe spectra.Chiratidzo hachifanirwe kusanganiswa nependi flakes.
Wana mifananidzo yeRaman uchishandisa mufananidzo pixel saizi dze2 µm uye 3 µm.Spectral analysis yakaitwa pamusoro pepamusoro pechikamu chepamusoro uye maitiro ekuzivikanwa akabatsirwa nekushandiswa kwemaitiro akadai sekutsvaga kwezvikamu zvakasiyana-siyana zvichienzaniswa nemaraibhurari anotengeswa.
Mupunga.1. Dhiagiramu yeyakajairwa ina-layer yemotokari pendi sampuro (kuruboshwe).Cross-sectional vhidhiyo mosaic yependi machipisi akatorwa pamusuwo wemota (kurudyi).Mufananidzo Chikwereti: Thermo Fisher Scientific - Zvishandiso uye Structural Analysis
Kunyange zvazvo nhamba yezvikamu zvependi flakes mumuenzaniso inogona kusiyana, sampuli dzinowanzoita dzinenge zvidimbu zvina (Mufananidzo 1).Iyo layer inoiswa yakananga kune simbi substrate ndeye electrophoretic primer (inenge 17-25 µm mukobvu) inoshanda kuchengetedza simbi kubva kune zvakatipoteredza uye inoshanda senzvimbo inokwirisa kune anotevera akaturikidzana epende.
Iro rinotevera rinowedzera primer, putty (inenge 30-35 microns gobvu) kuti ipe nzvimbo yakatsetseka kune inotevera nhevedzano yepende.Ipapo kunouya base jasi kana base jasi (rinenge 10-20 µm gobvu) rinosanganisira base pendi pigment.Iyo yekupedzisira dhizaini inoonekera yekudzivirira layer (inenge 30-50 microns gobvu) iyo inopawo kupenya kupedzisa.
Rimwe rematambudziko makuru nependi trace analysis nderekuti haasi ese akaturikidzana ependi pamotokari yepakutanga aripo semachipisi ependi uye mavanga.Mukuwedzera, masampuli kubva kumatunhu akasiyana anogona kunge aine zvinyorwa zvakasiyana.Semuyenzaniso, machipisi ependi pabhampa anogona kunge aine bumper material nependi.
Mufananidzo unooneka wepamuchinjikwa wependi chip inoratidzwa muMufananidzo 1. Zvikamu zvina zvinoonekwa mumufananidzo unooneka, unopindirana nemakumbo mana anozivikanwa nekuongorora infrared.
Mushure mekugadzira mepu yese chikamu chemuchinjikwa, mitsara yega yega yakaonekwa pachishandiswa FTIR mifananidzo yenzvimbo dzakasiyana dzepamusoro.Representative spectra uye yakabatana FTIR mifananidzo yezvikamu zvina zvinoratidzwa muFig.2. Mutsara wekutanga waienderana neyakajeka acrylic coating inosanganisira polyurethane, melamine (peak pa815 cm-1) uye styrene.
Chikamu chechipiri, chigadziko (ruvara) chigadziko uye chidimbu chakajeka chakafanana nemakemikari uye chinosanganisira acrylic, melamine uye styrene.
Kunyangwe iwo akafanana uye pasina chaiwo pigment peaks akaonekwa, iyo spectra ichiri kuratidza misiyano, kunyanya maererano nekunyanya kusimba.Layer 1 spectrum inoratidza akasimba peaks ari 1700 cm-1 (polyurethane), 1490 cm-1, 1095 cm-1 (CO) uye 762 cm-1.
Peak intensity mu spectrum ye layer 2 inowedzera pa 2959 cm-1 (methyl), 1303 cm-1, 1241 cm-1 (ether), 1077 cm-1 (ether) uye 731 cm-1.Iyo spectrum yedenga repamusoro rinoenderana neraibhurari spectrum yealkyd resin yakavakirwa paisophthalic acid.
Iyo yekupedzisira jasi re e-coat primer is epoxy uye pamwe polyurethane.Pakupedzisira, mhedzisiro yacho yaienderana neinowanzo kuwanikwa mumapende emotokari.
Ongororo yezvikamu zvakasiyana muchikamu chimwe nechimwe chakaitwa pachishandiswa maraibhurari eFTIR anotengeswa, kwete dhatabhesi rependi yemotokari, saka nepo machisi achimiririra, anogona kunge asiri iwo akakwana.
Kushandisa dhatabhesi yakagadzirirwa rudzi urwu rwekuongorora kuchawedzera kuoneka kwekuita, modhi uye gore remotokari.
Mufananidzo 2. Mumiririri FTIR spectra yezvikamu zvina zvakaonekwa muchikamu chemuchinjikwa chependi yegonhi remotokari.Mifananidzo ye infrared inogadzirwa kubva kumatunhu epamusoro ane hukama neamwe akaturikidzana uye akaiswa pamusoro peiyo vhidhiyo mufananidzo.Nzvimbo dzakatsvuka dzinoratidza nzvimbo yezvikamu zvega.Uchishandisa aperture ye10 x 10 µm2 uye nhanho saizi ye5 µm, mufananidzo weinfrared unovhara nzvimbo ye370 x 140 µm2.Mufananidzo Chikwereti: Thermo Fisher Scientific - Zvishandiso uye Structural Analysis
Pamusoro pemuonde.3 inoratidza mufananidzo wevhidhiyo wepamuchinjikwa chikamu chebumper pendi machipisi, angangoita matatu akaturikidzana anooneka zvakajeka.
Infrared cross-sectional mifananidzo inosimbisa kuvapo kwezvikamu zvitatu zvakasiyana (Fig. 4).Iyo yekunze dhizaini ijasi rakajeka, ringangove polyurethane uye acrylic, iyo yaienderana kana ichienzaniswa neyakajeka jasi spectra mumaraibhurari ezvekutengesa forensic.
Kunyangwe iwo maratidziro echigadziko (ruvara) runyoro rwakanyanya kufanana neaya akajeka akavhara, achiri akasiyana zvakakwana kuti asiyaniswe nekunze kwekunze.Pane misiyano yakakura mukusimba kwehukama hwepamusoro.
Iyo yechitatu layer inogona kunge iri bumper material pachayo, inosanganisira polypropylene uye talc.Talc inogona kushandiswa seinosimbisa kuzadza kwe polypropylene kusimudzira zvimiro zvezvinhu.
Ose majasi ekunze aienderana neaya aishandiswa mupende yemotokari, asi hapana chaiwo pigment peaks akaonekwa muprimer jasi.
Mupunga.3. Vhidhiyo mosaic yechikamu chemuchinjikwa chependi machipisi akatorwa mubhampa yemota.Chikwereti chemufananidzo: Thermo Fisher Scientific - Materials uye Structural Analysis
Mupunga.4. Inomiririra FTIR spectra yezvikamu zvitatu zvakaonekwa mumuchinjikwa chikamu chependi machipisi pabhampa.Mifananidzo ye infrared inogadzirwa kubva kumatunhu epamusoro ane hukama neamwe akaturikidzana uye akaiswa pamusoro peiyo vhidhiyo mufananidzo.Nzvimbo dzakatsvuka dzinoratidza nzvimbo yezvikamu zvega.Uchishandisa aperture ye10 x 10 µm2 uye nhanho saizi ye5 µm, mufananidzo weinfrared unovhara nzvimbo ye535 x 360 µm2.Mufananidzo Chikwereti: Thermo Fisher Scientific - Zvishandiso uye Structural Analysis
Raman imaging microscopy inoshandiswa kuongorora nhevedzano yezvikamu zvemuchinjikwa kuti uwane rumwe ruzivo nezve sampuli.Nekudaro, iyo Raman ongororo yakaomeswa neiyo fluorescence inoburitswa nemuenzaniso.Akawanda akasiyana laser masosi (455 nm, 532 nm uye 785 nm) akaedzwa kuti aongorore chiyero pakati pefluorescence intensity uye Raman chiratidzo chekusimba.
Kuongororwa kwependi machipisi pamagonhi, mhedzisiro yakanakisa inowanikwa nelaser ine wavelength ye455 nm;kunyange zvazvo fluorescence ichiripo, kugadzirisa kwepasi kunogona kushandiswa kuipikisa.Nekudaro, nzira iyi haina kubudirira pane epoxy layer nekuti iyo fluorescence yaive yakanyanya kushomeka uye zvinhu zvaigona kukuvara nelaser.
Kunyangwe mamwe lasers ari nani pane mamwe, hapana laser yakakodzera epoxy ongororo.Raman cross-sectional ongororo yependi machipisi pane bumper uchishandisa 532 nm laser.Mupiro wefluorescence uchiripo, asi wakabviswa nekugadzirisa kwekutanga.
Mupunga.5. Mumiririri Raman spectra yezvikamu zvitatu zvekutanga zvegonhi remotokari chip sample (kurudyi).Chikamu chechina (epoxy) chakarasika panguva yekugadzirwa kwemuenzaniso.Iyo spectra yaive yekutanga yakagadziriswa kubvisa mhedzisiro yefluorescence uye yakaunganidzwa uchishandisa 455 nm laser.Nzvimbo ye116 x 100 µm2 yakaratidzwa uchishandisa saizi yepixel ye2 µm.Muchinjika-chikamu vhidhiyo mosaic (kumusoro kuruboshwe).Multidimensional Raman Curve Resolution (MCR) cross-sectional mufananidzo (pazasi kuruboshwe).Mufananidzo Chikwereti: Thermo Fisher Scientific - Zvishandiso uye Structural Analysis
Raman kuongororwa kwechikamu chemuchinjikwa chechidimbu chepende yegonhi remotokari inoratidzwa mumufananidzo 5;iyi sampuli haina kuratidza epoxy layer nekuti yakarasika panguva yekugadzirira.Nekudaro, sezvo Raman kuongororwa kweiyo epoxy layer yakawanikwa iine dambudziko, izvi hazvina kutorwa sedambudziko.
Kuvapo kwe styrene kunotonga muRaman spectrum ye layer 1, nepo carbonyl peak iri shoma zvakanyanya kupfuura muIR spectrum.Kuenzaniswa neFTIR, kuongororwa kweRaman kunoratidza mutsauko wakakura mune spectra yekutanga neyechipiri matanda.
Iyo yepedyo yeRaman mechi kune base jasi ndeye perylene;kunyangwe isiri iyo chaiyo match, perylene derivatives inozivikanwa kuti inoshandiswa mune pigment mupendi yemotokari, saka inogona kumiririra pigment muruvara runyoro.
Iyo yepamusoro spectra yaienderana neisophthalic alkyd resins, zvisinei ivo vakaonawo kuvepo kwetitanium dioxide (TiO2, rutile) mumasamples, izvo dzimwe nguva zvainetsa kuona neFTIR, zvichienderana neiyo spectral cutoff.
Mupunga.6. Mumiririri weRaman wemuenzaniso wemachipisi ependi pane bumper (kurudyi).Iyo spectra yaive yekutanga yakagadziriswa kuti ibvise mhedzisiro yefluorescence uye yakaunganidzwa uchishandisa 532 nm laser.Nzvimbo ye195 x 420 µm2 yakaratidzwa uchishandisa saizi yepixel ye3 µm.Muchinjika-chikamu vhidhiyo mosaic (kumusoro kuruboshwe).Raman MCR mufananidzo wechikamu chemuchinjikwa (pazasi kuruboshwe).Chikwereti chemufananidzo: Thermo Fisher Scientific - Materials uye Structural Analysis
Pamusoro pemuonde.6 inoratidza mhedzisiro yeRaman yekuparadzira chikamu chemuchinjikwa chependi chips pane bumper.Imwe yekuwedzera (layer 3) yakawanikwa iyo yakanga isati yaonekwa neFTIR.
Pedyo nekunze kwekunze ndeye copolymer ye styrene, ethylene uye butadiene, asi panewo humbowo hwekuvapo kwechimwe chikamu chisingazivikanwi, sezvinoratidzwa nediki risingatsananguriki carbonyl peak.
Chimiro chejasi rejasi chinogona kuratidza kuumbwa kwepigment, sezvo iyo spectrum inoenderana neimwe nhanho kune phthalocyanine komputa inoshandiswa se pigment.
Iyo yaimbozivikanwa danga yakatetepa kwazvo (5 µm) uye chikamu inoumbwa nekabhoni uye rutile.Nekuda kwekukora kweiyi layer uye nenyaya yekuti TiO2 uye kabhoni yakaoma kuona neFTIR, hazvishamise kuti havana kuonekwa neIR ongororo.
Zvinoenderana nemhedzisiro yeFT-IR, yechina layer (iyo bumper material) yakaonekwa sepolypropylene, asi ongororo yeRaman yakaratidzawo kuvepo kwekabhoni.Kunyangwe kuvepo kwe talc inocherechedzwa muFITR hakugone kubviswa, chiziviso chaicho hachigone kuitwa nekuti inoenderana neRaman peak idiki.
Pendi dzemotokari musanganiswa wakaoma wezvigadzirwa, uye nepo izvi zvichigona kupa ruzivo rwakawanda rwekuziva, zvinoitawo kuti kuongorora kuve dambudziko guru.Pendi chip mamaki anogona kunyatsoonekwa uchishandisa Nicolet RaptIR FTIR maikorosikopu.
FTIR inzira isingaparadze yekuongorora iyo inopa ruzivo rwakakosha nezve akasiyana akaturikidzana uye zvikamu zvependi yemotokari.
Ichi chinyorwa chinokurukura nezve spectroscopic ongororo yemapende akaturikidzana, asi kunyatsoongorora kwemhedzisiro, kungave kuburikidza nekuenzanisa kwakananga nemotokari dzinofungidzirwa kana kuburikidza neakazvitsaurira spectral dhatabhesi, inogona kupa ruzivo rwakanyanya kuenderana nehumbowo kune kwahunobva.