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Pakachitika ngozi yapamsewu ndipo imodzi mwagalimotoyo ichoka pamalopo, ma laboratories azamalamulo nthawi zambiri amakhala ndi udindo wopeza umboniwo.
Umboni wotsalira umaphatikizapo magalasi osweka, nyali zakutsogolo zosweka, nyali zakumbuyo, kapena mabampa, komanso ma skid marks ndi zotsalira za utoto.Galimoto ikagundana ndi chinthu kapena munthu, utotowo umatha kusuntha ngati mawanga kapena tchipisi.
Utoto wamagalimoto nthawi zambiri umakhala wosakanikirana wosakanikirana wazinthu zosiyanasiyana zomwe zimagwiritsidwa ntchito mumagulu angapo.Ngakhale kuvutikiraku kumapangitsa kusanthula, kumaperekanso zambiri zomwe zingakhale zofunikira pakuzindikiritsa magalimoto.
Raman microscopy ndi Fourier transform infrared (FTIR) ndi zina mwa njira zazikulu zomwe zingagwiritsidwe ntchito kuthetsa mavutowa ndikuthandizira kusanthula kosawonongeka kwa zigawo zinazake muzovala zonse.
Kusanthula kwa chip chip kumayamba ndi data yowoneka bwino yomwe ingafanane mwachindunji ndi zitsanzo zowongolera kapena kugwiritsidwa ntchito molumikizana ndi database kuti mudziwe kupanga, chitsanzo, ndi chaka chagalimoto.
Apolisi a Royal Canadian Mounted Police (RCMP) amasunga database imodzi yotere, Paint Data Query (PDQ) database.Ma laboratories azamalamulo omwe atenga nawo gawo amatha kupezeka nthawi iliyonse kuti athandizire kukonza ndikukulitsa nkhokwe.
Nkhaniyi ikuyang'ana pa sitepe yoyamba pakuwunika: kusonkhanitsa deta kuchokera ku tchipisi ta utoto pogwiritsa ntchito FTIR ndi Raman microscopy.
Zambiri za FTIR zidasonkhanitsidwa pogwiritsa ntchito maikulosikopu ya Thermo Scientific™ Nicolet™ RaptIR™ FTIR;Zambiri za Raman zidasonkhanitsidwa pogwiritsa ntchito maikulosikopu ya Thermo Scientific™ DXR3xi Raman.Tchipisi zopenta zidatengedwa kuchokera kumalo owonongeka agalimoto: imodzi idadulidwa kuchokera pachitseko, inayo kuchokera ku bamper.
Njira yokhazikika yophatikizira zitsanzo zam'mbali ndikuziponya ndi epoxy, koma ngati utomoni ulowa mu chitsanzo, zotsatira za kusanthula zitha kukhudzidwa.Pofuna kupewa izi, zidutswa za utoto zinayikidwa pakati pa mapepala awiri a poly(tetrafluoroethylene) (PTFE) pamtanda.
Asanayambe kusanthula, gawo la mtanda la pepala la utoto linasiyanitsidwa pamanja ndi PTFE ndipo chipcho chinayikidwa pawindo la barium fluoride (BaF2).Kujambula kwa FTIR kunachitika pogwiritsa ntchito pobowo 10 x 10 µm2, cholinga chokongoletsedwa cha 15x ndi condenser, ndi phula la 5 µm.
Zitsanzo zomwezo zinagwiritsidwa ntchito pakuwunika kwa Raman kuti zisagwirizane, ngakhale gawo lochepa lawindo la BaF2 silikufunika.Ndizofunikira kudziwa kuti BaF2 ili ndi nsonga ya Raman pa 242 cm-1, yomwe imatha kuwonedwa ngati nsonga yofooka pamawonekedwe ena.Chizindikiro sichiyenera kugwirizanitsidwa ndi mapepala a penti.
Pezani zithunzi za Raman pogwiritsa ntchito zithunzi za pixel za 2 µm ndi 3 µm.Kusanthula kwa Spectral kunkachitika paziwongola dzanja zazikuluzikulu ndipo njira yozindikiritsira idathandizidwa ndi kugwiritsa ntchito njira monga kufufuza kwazinthu zambiri poyerekeza ndi malaibulale omwe amapezeka pamalonda.
Mpunga.1. Chithunzi cha chitsanzo cha utoto wamagalimoto osanjikiza anayi (kumanzere).Makanema ophatikizika amakanema a tchipisi tapenti otengedwa pachitseko chagalimoto (kumanja).Ngongole ya Zithunzi: Thermo Fisher Scientific - Zida ndi Kusanthula Kwamapangidwe
Ngakhale kuchuluka kwa zigawo za penti zopendekera pachitsanzo kumatha kusiyanasiyana, zitsanzo zimakhala ndi pafupifupi magawo anayi (Chithunzi 1).Chosanjikiza chomwe chimagwiritsidwa ntchito mwachindunji ku gawo lapansi lachitsulo ndi choyambira cha electrophoretic (pafupifupi 17-25 µm wandiweyani) chomwe chimateteza chitsulo ku chilengedwe ndipo chimakhala ngati malo okwera pamapepala otsatirawa.
Chotsatira chotsatira ndi choyambira chowonjezera, putty (pafupifupi 30-35 microns wandiweyani) kuti apereke malo osalala pamtundu wotsatira wa zigawo za utoto.Kenako pamabwera malaya oyambira kapena malaya oyambira (pafupifupi 10-20 µm wokhuthala) wokhala ndi utoto wa utoto woyambira.Chosanjikiza chomaliza ndi chosanjikiza chodzitchinjiriza (pafupifupi 30-50 microns wandiweyani) chomwe chimaperekanso kutha kowala.
Limodzi mwamavuto akulu pakuwunika kwa utoto ndikuti simitundu yonse ya utoto pagalimoto yoyambira yomwe ilipo ngati tchipisi ta utoto ndi zilema.Kuphatikiza apo, zitsanzo zochokera kumadera osiyanasiyana zimatha kukhala ndi zolemba zosiyanasiyana.Mwachitsanzo, tchipisi ta penti pa bampa imatha kukhala ndi zinthu zokulirapo komanso utoto.
Chithunzi chowonekera chamtundu wa chip chojambula chikuwonetsedwa mu Chithunzi 1. Zigawo zinayi zikuwonekera mu chithunzi chowonekera, chomwe chimagwirizana ndi zigawo zinayi zomwe zimadziwika ndi kusanthula kwa infrared.
Pambuyo pojambula gawo lonse la mtanda, zigawo zapadera zidadziwika pogwiritsa ntchito zithunzi za FTIR za madera osiyanasiyana apamwamba.Mawonekedwe oyimira ndi zithunzi zofananira za FTIR za zigawo zinayi zikuwonetsedwa mu Mkuyu.2. Wosanjikiza woyamba amafanana ndi zokutira zowonekera za acrylic zomwe zimakhala ndi polyurethane, melamine (pamwamba pa 815 cm-1) ndi styrene.
Chigawo chachiwiri, maziko (mtundu) wosanjikiza ndi wosanjikiza bwino ndi mankhwala ofanana ndipo amakhala acrylic, melamine ndi styrene.
Ngakhale kuti ndi ofanana ndipo palibe nsonga zamtundu wa pigment zomwe zadziwika, mawonekedwewa akuwonetsabe kusiyana, makamaka ponena za kuchulukira kwapamwamba.Gulu 1 sipekitiramu limasonyeza nsonga amphamvu pa 1700 cm-1 (polyurethane), 1490 cm-1, 1095 cm-1 (CO) ndi 762 cm-1.
Kuchuluka kwapamwamba pamtundu wa 2 wosanjikiza kumawonjezeka pa 2959 cm-1 (methyl), 1303 cm-1, 1241 cm-1 (ether), 1077 cm-1 (ether) ndi 731 cm-1.Mawonekedwe a pamwamba pake amafanana ndi laibulale ya alkyd resin yotengera isophthalic acid.
Chovala chomaliza cha e-coat primer ndi epoxy ndipo mwina polyurethane.Pamapeto pake, zotsatira zake zinali zogwirizana ndi zomwe zimapezeka kawirikawiri mu utoto wamagalimoto.
Kuwunika kwa magawo osiyanasiyana pagawo lililonse kunachitika pogwiritsa ntchito malaibulale a FTIR omwe amapezeka pamalonda, osati zolemba zamapenti zamagalimoto, kotero ngakhale machesi akuyimira, mwina sangakhale otsimikiza.
Kugwiritsa ntchito database yopangidwira kusanthula kwamtunduwu kudzakulitsa kuwonekera ngakhale kupanga, mtundu ndi chaka chagalimoto.
Chithunzi 2. Woyimilira FTIR mawonekedwe a zigawo zinayi zozindikirika pagawo lopingasa la utoto wonyezimira wa chitseko chagalimoto.Zithunzi za infrared zimapangidwa kuchokera kumadera apamwamba omwe amalumikizidwa ndi zigawo zapayekha ndikuyikidwa pamwamba pa chithunzi cha kanema.Madera ofiira amasonyeza malo a zigawo za munthu aliyense.Pogwiritsa ntchito kabowo ka 10 x 10 µm2 ndi kukula kwa 5 µm, chithunzi cha infrared chimakwirira kudera la 370 x 140 µm2.Ngongole ya Zithunzi: Thermo Fisher Scientific - Zida ndi Kusanthula Kwamapangidwe
Pa mkuyu.3 ikuwonetsa chithunzi cha kanema cha gawo lalikulu la tchipisi ta utoto, osachepera magawo atatu akuwoneka bwino.
Zithunzi zamtundu wa infrared zimatsimikizira kukhalapo kwa zigawo zitatu zosiyana (mkuyu 4).Chosanjikiza chakunja ndi chovala chowoneka bwino, chotheka kuti polyurethane ndi acrylic, chomwe chinali chosasinthika poyerekeza ndi mawonekedwe owoneka bwino m'malaibulale azamalamulo azamalonda.
Ngakhale kuti mawonekedwe a tsinde (mtundu) akuphimba ndi ofanana kwambiri ndi chovala choyera, akadali osiyana mokwanira kuti asiyanitsidwe ndi kunja.Pali kusiyana kwakukulu pakati pa kuchuluka kwa nsonga za nsonga.
Wosanjikiza wachitatu akhoza kukhala bumper chuma palokha, wopangidwa polypropylene ndi talc.Talc itha kugwiritsidwa ntchito ngati chowonjezera chowonjezera cha polypropylene kupititsa patsogolo kapangidwe kazinthuzo.
Zovala zakunja zonse ziwirizi zinali zogwirizana ndi zomwe zimagwiritsidwa ntchito popaka utoto wamagalimoto, koma palibe nsonga zamtundu wa pigment zomwe zidadziwika mu malaya oyambira.
Mpunga.3. Makanema ojambulidwa pagawo lopingasa la tchipisi tapenti otengedwa ku bumper yagalimoto.Ngongole yazithunzi: Thermo Fisher Scientific - Zipangizo ndi Kusanthula Kwamapangidwe
Mpunga.4. Woyimira FTIR mawonekedwe a zigawo zitatu zozindikiridwa mugawo lopingasa la tchipisi ta utoto pa bampa.Zithunzi za infrared zimapangidwa kuchokera kumadera apamwamba omwe amalumikizidwa ndi zigawo zapayekha ndikuyikidwa pamwamba pa chithunzi cha kanema.Madera ofiira amasonyeza malo a zigawo za munthu aliyense.Pogwiritsa ntchito kabowo ka 10 x 10 µm2 ndi kukula kwa 5 µm, chithunzi cha infrared chimakwirira kudera la 535 x 360 µm2.Ngongole ya Zithunzi: Thermo Fisher Scientific - Zida ndi Kusanthula Kwamapangidwe
Raman imaging microscopy imagwiritsidwa ntchito kusanthula magawo angapo kuti adziwe zambiri zachitsanzocho.Komabe, kusanthula kwa Raman kumakhala kovuta chifukwa cha fulorosenti yotulutsidwa ndi chitsanzo.Magwero angapo a laser (455 nm, 532 nm ndi 785 nm) adayesedwa kuti awone kuchulukana pakati pa mphamvu ya fluorescence ndi mphamvu ya chizindikiro cha Raman.
Pakuwunika tchipisi ta utoto pazitseko, zotsatira zabwino zimapezedwa ndi laser yokhala ndi kutalika kwa 455 nm;ngakhale fluorescence idakalipo, kuwongolera koyambira kungagwiritsidwe ntchito kuthana nayo.Komabe, njira iyi sinali bwino pazigawo za epoxy chifukwa fulorosisi inali yochepa kwambiri ndipo zinthuzo zinkawonongeka ndi laser.
Ngakhale ma lasers ena ndi abwino kuposa ena, palibe laser yomwe ili yoyenera kusanthula epoxy.Kusanthula kwapang'onopang'ono kwa Raman kwa tchipisi ta utoto pa bumper pogwiritsa ntchito laser 532 nm.Kuthandizira kwa fluorescence kulipobe, koma kuchotsedwa ndi kukonza koyambira.
Mpunga.5. Woimira Raman mawonekedwe a magawo atatu oyambirira a chitsanzo cha chip chitseko cha galimoto (kumanja).Chigawo chachinayi (epoxy) chinatayika panthawi yopanga chitsanzo.Zowonera zidakonzedwa kuti zichotse mphamvu ya fluorescence ndikusonkhanitsidwa pogwiritsa ntchito laser 455 nm.Malo a 116 x 100 µm2 adawonetsedwa pogwiritsa ntchito kukula kwa pixel kwa 2 µm.Makanema amitundu yosiyanasiyana (chapamwamba kumanzere).Multidimensional Raman Curve Resolution (MCR) chithunzi chopingasa (pansi kumanzere).Ngongole ya Zithunzi: Thermo Fisher Scientific - Zida ndi Kusanthula Kwamapangidwe
Kusanthula kwa Raman kwa gawo la mtanda wa pepala lachitseko cha galimoto kukuwonetsedwa mu Chithunzi 5;chitsanzo ichi sichisonyeza epoxy wosanjikiza chifukwa anataya pokonzekera.Komabe, popeza kusanthula kwa Raman kwa epoxy layer kunapezeka kuti kunali kovuta, izi sizinaganizidwe ngati vuto.
Kukhalapo kwa styrene kumayang'anira mawonekedwe a Raman a wosanjikiza 1, pomwe nsonga ya carbonyl imakhala yocheperako kuposa mawonekedwe a IR.Poyerekeza ndi FTIR, kusanthula kwa Raman kukuwonetsa kusiyana kwakukulu pamawonekedwe agawo loyamba ndi lachiwiri.
Machesi oyandikira kwambiri a Raman ku malaya oyambira ndi perylene;ngakhale sizofanana kwenikweni, zotumphukira za perylene zimadziwika kuti zimagwiritsidwa ntchito popanga utoto wamagalimoto, kotero zimatha kuyimira pigment mumtundu wosanjikiza.
Mawonekedwe a pamwamba anali ogwirizana ndi isophthalic alkyd resins, komabe adazindikiranso kupezeka kwa titanium dioxide (TiO2, rutile) m'masampuli, zomwe nthawi zina zinali zovuta kuzizindikira ndi FTIR, kutengera mawonekedwe a spectral cutoff.
Mpunga.6. Woimira Raman sipekitiramu wa chitsanzo cha tchipisi utoto pa bampa (kumanja).Mawonedwewo adakonzedwa kuti achotse mphamvu ya fluorescence ndikusonkhanitsidwa pogwiritsa ntchito laser 532 nm.Malo a 195 x 420 µm2 adawonetsedwa pogwiritsa ntchito kukula kwa pixel kwa 3 µm.Makanema amitundu yosiyanasiyana (chapamwamba kumanzere).Chithunzi cha Raman MCR cha gawo lamtanda (pansi kumanzere).Ngongole yazithunzi: Thermo Fisher Scientific - Zipangizo ndi Kusanthula Kwadongosolo
Pa mkuyu.6 ikuwonetsa zotsatira za Raman kumwazikana kwa magawo amtundu wa tchipisi ta utoto pa bamper.Chigawo chowonjezera (wosanjikiza 3) chapezeka chomwe sichinazindikiridwe ndi FTIR.
Pafupi ndi wosanjikiza wakunja ndi copolymer wa styrene, ethylene ndi butadiene, koma palinso umboni wa kukhalapo kwa chigawo china chosadziwika, monga umboni wa nsonga yaing'ono yosadziwika ya carbonyl.
Kuchuluka kwa malaya oyambira kumatha kuwonetsa mawonekedwe a pigment, popeza mawonekedwe ake amafanana ndi gulu la phthalocyanine lomwe limagwiritsidwa ntchito ngati pigment.
Chosanjikiza chomwe sichinadziwikepo ndi choonda kwambiri (5 µm) ndipo chinapangidwa ndi mpweya ndi rutile.Chifukwa cha makulidwe a wosanjikiza uwu komanso kuti TiO2 ndi kaboni ndizovuta kuzizindikira ndi FTIR, sizosadabwitsa kuti sanazindikiridwe ndi kusanthula kwa IR.
Malinga ndi zotsatira za FT-IR, wosanjikiza wachinayi (chinthu chachikulu) adadziwika kuti ndi polypropylene, koma kuwunika kwa Raman kunawonetsanso kukhalapo kwa kaboni.Ngakhale kupezeka kwa talc kuwonedwa mu FITR sikungayikidwe, chizindikiritso cholondola sichingapangidwe chifukwa nsonga yofananira ya Raman ndi yaying'ono kwambiri.
Utoto wamagalimoto ndizovuta zosakaniza zosakaniza, ndipo ngakhale izi zitha kupereka zambiri zozindikiritsa, zimapangitsanso kusanthula kukhala kovuta kwambiri.Zizindikiro za utoto wa utoto zitha kuzindikirika bwino pogwiritsa ntchito maikulosikopu ya Nicolet RaptIR FTIR.
FTIR ndi njira yowunikira yosawononga yomwe imapereka chidziwitso chofunikira pamagawo osiyanasiyana ndi zigawo za utoto wamagalimoto.
Nkhaniyi ikufotokoza za kusanthula kwazithunzi za zigawo za utoto, koma kusanthula mozama kwa zotsatira zake, mwina poyerekezera mwachindunji ndi magalimoto omwe akuwakayikira kapena kudzera m'ma database odzipatulira, atha kupereka chidziwitso cholondola kuti chifanane ndi umboni ndi gwero lake.