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Microbial corrosion (MIC) idambudziko guru mumaindasitiri mazhinji nekuti rinogona kukonzera kurasikirwa kukuru kwehupfumi.Super duplex Stainless simbi 2707 (2707 HDSS) inoshandiswa munzvimbo dzemugungwa nekuda kwekunaka kwayo kwemakemikari kuramba.Nekudaro, kuramba kwayo kuMIC hakuna kuratidzwa.Chidzidzo ichi chakaongorora maitiro eMIC 2707 HDSS akakonzerwa nebhakteria remugungwa reaerobic Pseudomonas aeruginosa.Electrochemical analysis yakaratidza kuti pamberi pePseudomonas aeruginosa biofilm mu 2216E yepakati, simba rekuora rakashandurwa zvakanaka, uye kusvibiswa kwemazuva ano kwakawedzera.Mhedzisiro yeX-ray photoelectron spectroscopy (XPS) ongororo yakaratidza kudzikira kweiyo Cr yemukati pane sampuli yepasi pasi peiyo biofilm.Ongororo yemifananidzo yegomba yakaratidza kuti Pseudomonas aeruginosa biofilms yakaburitsa yakadzika gomba kudzika kwe0.69 µm mushure memazuva gumi nemana etsika.Kunyangwe izvi zvidiki, zvinoratidza kuti 2707 HDSS haina kudzivirirwa zvachose kumhedzisiro yeP. aeruginosa biofilms paMIC.
Duplex Stainless simbi (DSS) inoshandiswa zvakanyanya mumaindasitiri akasiyana siyana nekuda kwemusanganiswa wakakwana weakanakisa ma mechanical zvivakwa uye corrosion resistance1,2.Zvisinei, gomba remunharaunda rinogona kuitika, izvo zvinogona kukanganisa kuvimbika kwesimbi iyi 3, 4.DSS haina kudzivirirwa kubva kune microbial corrosion (MIC)5,6.Kunyangwe huwandu hwekushandisa hweDSS hwakakura kwazvo, kuchine nharaunda uko kushora kweDSS hakuna kukwana kushandiswa kwenguva refu.Izvi zvinoreva kuti zvinhu zvinodhura zvakanyanya zvine corrosion resistance inodiwa.Jeon et al.7 vakawana kuti kunyange super duplex simbi isina tsvina (SDSS) ine zvimwe zvinogumira maererano nekushomeka kwekuora.Naizvozvo, panodiwa super duplex Stainless simbi (HDSS) ine yakakwira corrosion kuramba mune mamwe maapplication.Izvi zvakakonzera kugadzirwa kweHDSS yakasanganiswa zvakanyanya.
Kurwisana kwekuora kweDSS kunotarirwa nehuwandu hwe-α-phase kusvika γ-phase uye nzvimbo dzakapera muCr, Mo uye W pedyo nechikamu chechipiri8,9,10.HDSS ine yakakwira yemukati yeCr, Mo uye N11, iyo inopa yakanakisa corrosion kuramba uye kukosha kwepamusoro (45-50) yakaenzana pitting resistance value (PREN), iyo inotsanangurwa ne wt.% Cr + 3.3 (wt.% Mo + 0, 5 wt % W) + 16 wt %.N12.Kuramba kwayo kwakanakisa kwekuora kunoenderana nekuumbwa kwakaringana kunenge 50% ferritic (α) uye 50% austenitic (γ) zvikamu.HDSS yakavandudza ma mechanical zvivakwa uye yakakwirira chlorine kuramba kana ichienzaniswa neyakajairika DSS13.Hunhu hwemakemikari corrosion.Kuvandudzwa kwekupokana kunowedzera kushandiswa kweHDSS munzvimbo dzine hukasha dzechloride dzakadai senzvimbo dzemugungwa.
MIC idambudziko rakakura mumaindasitiri mazhinji, anosanganisira oiri negesi uye nekupa mvura14.MIC inoverengera makumi maviri muzana yezvese kukuvara kwekuora15.MIC inonzi bioelectrochemical corrosion inogona kuonekwa munzvimbo dzakawanda16.Kuumbwa kwebiofilms pane simbi kunoshandura mamiriro e electrochemical uye nokudaro kunokanganisa maitiro ekuora.Zvinowanzogamuchirwa kuti MIC corrosion inokonzerwa ne biofilms14.Electrogenic microorganisms inodya simbi kuitira kuti iwane simba rekurarama17.Zvidzidzo zveMIC zvichangoburwa zvakaratidza kuti EET (extracellular electron transfer) ndiyo inodzikamisa MIC inokonzereswa neelectrogenic microorganisms.Zhang et al.18 vakaratidza kuti vayananisi vemarekitironi vanomhanyisa kutamisa maerekitironi pakati peDesulfovibrio vulgaris sessile masero uye 304 simbi isina tsvina, zvichikonzera kurwisa kwakanyanya kweMIC.Anning et al.19 uye Wenzlaff et al.20 zvakaratidza kuti biofilms ye corrosive sulfate-reducing bacteria (SRBs) inogona kutora maerekitironi zvakananga kubva kusimbi substrates, zvichikonzera kupinza kwakanyanya.
DSS inozivikanwa kuti inobatwa neMIC munhau dzine SRBs, iron-reducing bacteria (IRBs), etc. 21.Aya mabhakitiriya anokonzera gomba renzvimbo pamusoro peDSS pasi pe biofilm22,23.Kusiyana neDSS, zvishoma zvinozivikanwa nezve MIC HDSS24.
Pseudomonas aeruginosa ibhakitiriya reGram-negative, motile, rakaita setsvimbo iro rinoparadzirwa zvakanyanya muzvisikwa25.Pseudomonas aeruginosa zvakare ndiyo huru hutachiona inotarisira MIC yesimbi munzvimbo yegungwa26.Pseudomonas marudzi anobatanidzwa zvakananga mukuita corrosion uye anozivikanwa sevekutanga colonizers panguva biofilm formation27.Mahat et al.28 uye Yuan et al.29 yakaratidza kuti Pseudomonas aeruginosa inowedzera kuwedzera kukora kwesimbi yakapfava uye alloys munzvimbo dzemvura.
Chinangwa chikuru chebasa iri kudzidza maitiro eMIC e2707 HDSS akakonzerwa nebhakteria remugungwa aerobic Pseudomonas aeruginosa uchishandisa nzira dze electrochemical, nzira dzekuongorora pamusoro uye kuongororwa kwechigadzirwa chekuora.Zvidzidzo zveElectrochemical zvinosanganisira yakavhurika yedunhu mukana (OCP), mutsara polarization kuramba (LPR), electrochemical impedance spectroscopy (EIS) uye ine simba inogona polarization yakaitwa kudzidza maitiro eMIC 2707 HDSS.Kuongororwa kweEnergy dispersive spectroscopy (EDS) kunoitwa kuona zvinhu zvemakemikari panzvimbo dzine ngura.Mukuwedzera, kugadzikana kweoxide film passivation pasi pesimba remugungwa nharaunda ine Pseudomonas aeruginosa yakatemwa neX-ray photoelectron spectroscopy (XPS).Kudzika kwemakomba kwakayerwa pasi pe confocal laser scanning microscope (CLSM).
Tafura 1 inoratidza chimiro chemakemikari ye2707 HDSS.Tafura 2 inoratidza kuti 2707 HDSS ine yakanakisa mechanical zvivakwa zvine goho re650 MPa.Pamusoro pemuonde.1 inoratidza iyo optical microstructure yemhinduro kupisa yakabatwa 2707 HDSS.Mabhendi akareba ezvikamu zve austenitic uye ferritic pasina zvikamu zvechipiri zvinogona kuonekwa mune microstructure ine inenge 50% austenitic uye 50% ferritic phases.
Pamusoro pemuonde.2a inoratidza mukana wedunhu rakavhurika (Eocp) maringe nenguva ye2707 HDSS mu2216E abiotic medium uye Pseudomonas aeruginosa muto kwemazuva gumi nemana pa37°C.Yakawanikwa kuti yakanyanya kutaurwa shanduko muEocp yakaitika mumaawa makumi maviri nemana ekutanga.Eocp values muzviitiko zvese zviri zviviri yakakwira kusvika -145 mV (zvichipikisana neSCE) pamaawa angangoita gumi nematanhatu uye ichibva yadonha zvakanyanya kusvika -477 mV (inopesana neSCE) uye -236 mV (inopesana neSCE) kune isiri-biological samples uye P yehama. SCE) patina mashizha, zvichiteerana.Mushure memaawa makumi maviri nemana, kukosha kweEocp yePseudomonas aeruginosa 2707 HDSS yakaramba yakagadzikana pa -228 mV (ichienzaniswa neSCE), nepo kukosha kunoenderana neasiri-biological sampuro yaive -442 mV (ichienzaniswa neSCE).Eocp pamberi pePseudomonas aeruginosa yaive yakadzikira.
Electrochemical test ye2707 HDSS samples mune abiotic media uye Pseudomonas aeruginosa muto pa37°C:
(a) Shanduko muEocp nenguva yekuratidzwa, (b) polarization curve pazuva 14, (c) shanduko muRp nenguva yekuratidzwa, (d) shanduko mucorr nenguva yekuratidzwa.
Tafura 3 inoratidza electrochemical corrosion parameters ye2707 HDSS samples dzakafumurwa kune abiotic uye P. aeruginosa inoculated media mukati memazuva gumi nemana.Tangential extrapolation yeanodic uye cathodic curves kusvika kumharadzano yakabvumira kugadziriswa kwekuora kwezvino density (icorr), corrosion potential (Ecorr) uye Tafel slope (βα uye βc) maererano nemaitiro akaenzana30,31.
Sezvinoratidzwa mumufananidzo 2b, kukwira kumusoro kweP. aeruginosa curve kwakaguma nekuwedzera kweEcorr kana ichienzaniswa neabiotic curve.Iko icorr kukosha kwemuenzaniso une Pseudomonas aeruginosa, yakaenzana nehuwandu hwekuora, yakawedzera kusvika ku 0.328 µA cm-2, iyo yakakura zvakapetwa kana kupfuura iyo isiri-biological sample (0.087 µA cm-2).
LPR inzira yemhando yepamusoro ye electrochemical yekusaparadza kutaura kwekuongorora kwekuora.Yakashandiswawo kudzidza MIC32.Pamusoro pemuonde.2c inoratidza shanduko mukupikisa polarization (Rp) zvichienderana nenguva yekuratidzwa.Kukosha kweRp kunoreva kushomeka kwemarara.Mumaawa makumi maviri nemana ekutanga, Rp 2707 HDSS yakakwira pa1955 kΩ cm2 yezvisiri zvipenyu uye 1429 kΩ cm2 yePseudomonas aeruginosa specimens.Mufananidzo 2c unoratidzawo kuti kukosha kweRp kwakadzikira nekukurumidza mushure mezuva rimwe ndokuzoramba kusingachinjiki mumazuva gumi nematatu anotevera.Hwaro hweRp hwePseudomonas aeruginosa test specimen ingangoita 40 kΩ cm2, iri pasi zvakanyanya pane 450 kΩ cm2 kukosha kune isiri yebhayoloji test specimen.
Kukosha kweicorr kunoenzanirana neyunifomu yecorrosion rate.Kukosha kwayo kunogona kuverengerwa kubva kune inotevera Stern-Giri equation:
Maererano naZoe et al.33 iyo Tafel slope B yakatorwa seyakajairika kukosha kwe26 mV/dec mubasa iri.Pamusoro pemuonde.2d inoratidza kuti icorr ye2707 abiotic strain yakaramba yakagadzikana, nepo icorr yebhendi yePseudomonas aeruginosa yakachinja zvine simba nekusvetuka kukuru mushure memaawa makumi maviri nemana ekutanga.Iko icorr kukosha kwePseudomonas aeruginosa test sample yaive yakarongeka yehukuru hwepamusoro kupfuura iyo isiri yebhayoloji control.Iyi maitiro inoenderana nemhedzisiro yepolarization resistance.
EIS imwe nzira isingaparadzi inoshandiswa kuratidza maitiro e electrochemical pane corrosion interface34.Impedance spectra uye capacitance kuverenga kwezvimedu zvakafumurwa kune abiotic midhiya uye mhinduro dzePseudomonas aeruginosa, Rb ndiko kuramba kwepassive / biofilm yakaumbwa pamusoro peiyo tambo, Rct ndiyo yekuchaja yekufambisa kuramba, Cdl ndiyo yemagetsi yakapetwa kaviri.) uye QCPE yenguva dzose chikamu chinhu (CPE) parameters.Aya ma paramita akaongororwa zvakare nekuenzanisa data neyakafanana yemagetsi edunhu (EEC) modhi.
Pamusoro pemuonde.3 inoratidza zvakajairika Nyquist plots (a uye b) neBode plots (a' and b') ye2707 HDSS samples mune abiotic media uye Pseudomonas aeruginosa muto panguva dzakasiyana dzekuisa.Pamberi pePseudomonas aeruginosa, dhayamita yeNyquist loop inoderera.Iyo Bode plot (Fig. 3b ') inoratidza kuwedzera kweimpedance yose.Ruzivo nezve nguva yekuzorora nguva dzose inogona kuwanikwa kubva muchikamu maxima.Pamusoro pemuonde.4 inoratidza zvimiro zvemuviri uye inoenderana EEC yakavakirwa pane imwechete-layer (a) uye maviri-layer (b).CPE inounzwa muEEC modhi.Kubvumirwa kwayo uye impedance inoratidzwa sezvinotevera:
Mhando mbiri dzemuviri uye dzinoenderana maseketi ekukodzera iyo 2707 HDSS coupon impedance spectrum:
Ipo Y0 ihwo ukuru hweCPE, j inhamba yekufungidzira kana (-1) 1/2, ω ndiyo frequency yeangular, uye n ndiyo CPE simba chinhu chisingasviki one35.Iyo yekuchaja yekufambisa kuramba inversion (kureva 1 / Rct) inoenderana neiyo corrosion rate.Iyo yakaderera Rct kukosha inoreva huwandu hwepamusoro hwekuora27.Mushure memazuva gumi nemana ekuvharidzirwa, Rct yemuenzaniso wekuedzwa wePseudomonas aeruginosa yakasvika 32 kΩ cm2, iyo iri pasi pe489 kΩ cm2 ye-non-biological test sample (Table 4).
CLSM mifananidzo uye SEM mifananidzo mune fig.5 inoratidza zvakajeka kuti kufukidzwa kwebiofilm pamusoro peHDSS sampuro 2707 yaive yakaoma kwazvo mushure memazuva manomwe.Nekudaro, mushure memazuva gumi nemana iyo biofilm coating yakave shoma uye mamwe masero akafa akaonekwa.Tafura 5 inoratidza kukora kwebiofilm kwe2707 HDSS samples mushure memazuva manomwe negumi nemana ekusangana nePseudomonas aeruginosa.Hukuru hwebiofilm hwakachinja kubva pa23.4 µm mushure memazuva manomwe kuenda pa18.9 µm mushure memazuva gumi nemana.Avhareji biofilm ukobvu akasimbisawo maitiro aya.Yakadzikira kubva pa22.2 ± 0.7 μm mushure memazuva manomwe kusvika pa17.8 ± 1.0 μm mushure memazuva gumi nemana.
(a) 3-D CLSM mufananidzo pamazuva manomwe, (b) 3-D CLSM mufananidzo pamazuva gumi nemana, (c) SEM mufananidzo pamazuva manomwe, uye (d) SEM mufananidzo pamazuva gumi nemana.
EMF yakaburitsa makemikari zvinhu mubiofilm uye corrosion zvigadzirwa pamasampuli akafumurwa kuPseudomonas aeruginosa kwemazuva gumi nemana.Pamusoro pemuonde.Mufananidzo 6 unoratidza kuti zvinyorwa zveC, N, O, P mu biofilm uye corrosion zvigadzirwa zvakakwirira kudarika musimbi yakachena, sezvo zvinhu izvi zvakabatana ne biofilm uye metabolites yayo.Microorganisms inoda chete huwandu hweCr neFe.Izvo zvakakwirira zveCr uye Fe mune biofilm uye corrosion zvigadzirwa pamusoro peiyo sampuli inoratidza kurasikirwa kwezvinhu musimbi matrix semugumisiro wekuora.
Mushure memazuva gumi nemana, makomba ane uye asina P. aeruginosa akaonekwa pakati pe2216E.Isati yaiswa, pamusoro pemasamples yakanga yakatsetseka uye isina kukanganisa (Fig. 7a).Mushure mekuvhara uye kubviswa kwebiofilm uye corrosion zvigadzirwa, makomba akadzika pamusoro pemuenzaniso akaongororwa achishandisa CLSM, sezvakaratidzwa mumufananidzo 7b uye c.Hapana gomba riri pachena rakawanikwa pamusoro peiyo isiri-biological control (yakanyanya gomba kudzika 0.02 µm).Iyo yakadzika gomba yakadzika yakakonzerwa nePseudomonas aeruginosa yaive 0.52 µm mushure memazuva manomwe uye 0.69 µm mushure memazuva gumi nemana, zvichibva paavhareji yakadzika gomba kudzika kubva ku3 samples (10 yakanyanya gomba kudzika kwakasarudzwa kune yega sampuli) uye yakasvika 0. 42 ± 0.12 µm .uye 0.52 ± 0.15 µm, zvichiteerana (Tafura 5).Aya dimple kudzika kukosha idiki asi yakakosha.
(a) vasati vasangana;(b) mazuva gumi nemana munzvimbo ine abiotic;(c) Mazuva gumi nemana muP. aeruginosa muto.
Pamusoro pemuonde.Tafura 8 inoratidza XPS spectra yemhando dzakasiyana-siyana dzemasampuli, uye chemistry yakaongororwa kune imwe neimwe nzvimbo inopfupikiswa muTebhu 6. MuTebhu 6, maatomu ezvikamu zveFe neCr akanga akaderera zvikuru pamberi peP. aeruginosa (samples A uye B ) kupfuura mune zvisiri zvebhayoloji zvinodzora mitsara.(mienzaniso C uye D).Pamuenzaniso wePseudomonas aeruginosa, iyo Cr 2p core level spectral curve yakaiswa kuzvikamu zvina zvepamusoro zvine simba rekusunga (BE) ye574.4, 576.6, 578.3 uye 586.8 eV, iyo yakapihwa Cr, Cr2O3, CR(O3, CR(O3) uye CR(O3) 3, maererano (Fig. 9a uye b).Kune asiri biological samples, iyo spectra yeiyo core level Cr 2p muFig.9c uye d ine nhongonya mbiri dzeCr (BE 573.80 eV) neCr2O3 (BE 575.90 eV), zvichiteerana.Musiyano unoshamisa pakati peabiotic coupon neP. aeruginosa coupon yaive kuvepo kweCr6+ uye chikamu chakakwirira cheCr(OH)3 (BE 586.8 eV) pasi pe biofilm.
Broad surface XPS spectra ye2707 HDSS samples mune mbiri midhiya kwemazuva manomwe negumi nemana, zvichiteerana.
(a) Mazuva manomwe P. aeruginosa exposure, (b) mazuva gumi nemana P. aeruginosa exposure, (c) 7 days abiotic exposure, (d) 14 day abiotic exposure.
HDSS inoratidza yakakwira mwero wekupokana munzvimbo zhinji.Kim et al.2 vakashuma kuti HDSS UNS S32707 yakaonekwa seDSS yakanyanyisa doped ine PREN yakakura kudarika 45. The PREN kukosha kweHDSS sample 2707 mubasa iri yaiva 49. Izvi zvinokonzerwa nehuwandu hweCr uye huwandu hweMo uye Ni, iyo inobatsira munzvimbo dzine acidic uye nharaunda dzine huwandu hwakawanda hwekloridi.Mukuwedzera, iyo yakanyatsogadziriswa kuumbwa uye kukanganisa-isina microstructure inopa kugadzikana kwemaitiro uye kusagadzikana kwemarara.Kunyangwe yakanakisa kuramba kwemakemikari, iyo yekuyedza data mubasa iri inoratidza kuti 2707 HDSS haina kudzivirirwa zvachose kuPseudomonas aeruginosa biofilm MICs.
Electrochemical results yakaratidza kuti corrosion rate ye2707 HDSS muPseudomonas aeruginosa muto yakawedzera zvakanyanya mushure memazuva e14 kana ichienzaniswa nemamiriro ezvinhu asiri ehupenyu.Mumufananidzo 2a, kuderera kweEocp kwakaonekwa zvose mu abiotic medium uye muP. aeruginosa muto mumaawa makumi maviri nemana ekutanga.Mushure meizvozvo, iyo biofilm inopedza kuvhara pamusoro peiyo sampuli uye Eocp inova yakagadzikana.Nekudaro, iyo biotic Eocp level yaive yakakwira zvakanyanya kupfuura iyo abiotic Eocp level.Pane zvikonzero zvekutenda kuti musiyano uyu unobatanidzwa nekuumbwa kweP. aeruginosa biofilms.Pamusoro pemuonde.2g, iyo icorr kukosha kwe2707 HDSS yakasvika 0.627 µA cm-2 pamberi pePseudomonas aeruginosa, inova kurongeka kwehukuru hwepamusoro kupfuura iyo isiri yebhayoloji control (0.063 µA cm-2), iyo inoenderana neRct. kukosha kwakayerwa neEIS.Mumazuva mashoma ekutanga, iyo impedance values muP. aeruginosa muto yakawedzera nekuda kwekubatanidzwa kweP. aeruginosa masero uye biofilm kugadzirwa.Nekudaro, iyo impedance inodzikira kana iyo biofilm yakavhara zvachose iyo sampuli nzvimbo.Iyo yekudzivirira inorwiswa zvakanyanya nekuda kwekuumbwa kwebiofilm uye biofilm metabolites.Naizvozvo, kusaita ngura kunodzikira nekufamba kwenguva, uye madhipoziti ePseudomonas aeruginosa anokonzera kuora kwenzvimbo.Maitiro munzvimbo dzeabiotic akasiyana.Kupokana kwekuora kweiyo isiri-biological control yaive yakakwira zvakanyanya kupfuura kukosha kunowirirana kwemasampunzi akafumurwa kuPseudomonas aeruginosa muto.Pamusoro pezvo, kune abiotic samples, iyo Rct 2707 HDSS kukosha kwakasvika 489 kΩ cm2 pazuva regumi neina, iyo yakakwira ka15 kupfuura pamberi pePseudomonas aeruginosa (32 kΩ cm2).Saka, 2707 HDSS ine yakanakisa kusadzivirirwa nekuora munzvimbo ine hutachiona, asi haina kudzivirirwa kubva kuMIC kurwiswa nePseudomonas aeruginosa biofilm.
Izvi mhedzisiro zvinogona zvakare kucherechedzwa kubva kune polarization curves muFig.2b.Anodic branching inosanganiswa nePseudomonas aeruginosa biofilm formation uye metal oxidation reactions.Panguva imwecheteyo, iyo cathodic reaction ndiyo kuderedzwa kweokisijeni.Kuvapo kweP. aeruginosa kwakawedzera zvakanyanya corrosion current density, iyo yakanga iri pamusoro pekurongeka kwehukuru hwepamusoro kupfuura mukutonga kweabiotic.Izvi zvakaratidza kuti iyo Pseudomonas aeruginosa biofilm yakasimudzira kuparara kwenzvimbo kwe2707 HDSS.Yuan et al.29 vakawana kuti corrosion current density ye70/30 Cu-Ni alloy yakawedzerwa nePseudomonas aeruginosa biofilm.Izvi zvinogona kunge zvakakonzerwa ne biocatalysis yekuderedzwa kweokisijeni nePseudomonas aeruginosa biofilm.Kuona uku kunogonawo kutsanangura iyo MIC 2707 HDSS mubasa iri.Aerobic biofilms inogona zvakare kuderedza iyo oksijeni yemukati pasi pawo.Nokudaro, kuramba kudzorerazve simbi neokisijeni inogona kuva chinhu chinokonzera MIC mubasa iri.
Dickinson et al.38 yakaratidza kuti chiyero chemakemikari uye electrochemical reaction zvakananga zvinoenderana nekuita kwemetabolism yebhakitiriya yakanamirwa kune sampuli yepamusoro uye nemhando yezvigadzirwa zvekuora.Sezvinoratidzwa mumufananidzo 5 uye Tafura 5, nhamba yemasero uye biofilm ukobvu yakaderera mushure memazuva gumi nemana.Izvi zvinogona kutsanangurwa zvine musoro nenyaya yekuti mushure memazuva gumi nemana mazhinji emaseru akabatidzwa pa2707 HDSS pamusoro akafa nekuda kwekuderera kwechikafu mu2216E medium kana kuburitswa kweiyo simbi ine chepfu kubva ku2707 HDSS matrix.Uku ndiko kudzikisira kwe batch experiments.
Mune basa iri, Pseudomonas aeruginosa biofilm yakakurudzira kuderedzwa kwenharaunda yeCr uye Fe pasi pe biofilm pamusoro pe2707 HDSS (Fig. 6).MuTebhenekeri 6, Fe uye Cr yakaderera mumuenzaniso D kana ichienzaniswa nemuenzaniso C, zvichiratidza kuti Fe uye Cr kuparara kwakakonzerwa neP. aeruginosa biofilm yakachengetwa mushure mekutanga kwemazuva manomwe.Iyo 2216E nharaunda inoshandiswa kutevedzera nharaunda yegungwa.Iyo ine 17700 ppm Cl-, iyo inofananidzwa nezvayo mune yakasikwa mvura yegungwa.Kuvapo kwe17700 ppm Cl- chaive chikonzero chikuru chekuderera kweCr mu7-day uye 14-day isiri-biological samples yakaongororwa neXPS.Kuenzaniswa nemuenzaniso wekuedzwa wePseudomonas aeruginosa, kuparara kweCr mumuenzaniso weabiotic test ishoma nekuda kwekupikisa kwakasimba kwe2707 HDSS kune chlorine munzvimbo yeabiotic.Pamusoro pemuonde.9 inoratidza kuvepo kweCr6 + mufirimu rinopfuura.Izvi zvinogona kunge zvine chekuita nekubviswa kweCr kubva panzvimbo dzesimbi neP. aeruginosa biofilms, sezvakataurwa naChen naClayton39.
Nekuda kwekukura kwebhakitiriya, iyo pH kukosha kweyepakati isati yasvika uye mushure mekudzvanywa yaive 7.4 uye 8.2, zvichiteerana.Saka, kuora kwe organic acids hakugoneki kuita basa iri pasi peP. aeruginosa biofilms nekuda kwepH yakawandisa muhuwandu hwehuwandu.Iyo pH yeasiri-biological control medium haina kushanduka zvakanyanya (kubva pakutanga 7.4 kusvika yekupedzisira 7.5) mukati memazuva gumi nemana ekuyedzwa.Kuwedzera kwepH mune inoculum medium mushure mekuvharwa kwakabatanidzwa nebasa re metabolic rePseudomonas aeruginosa, uye mhedzisiro yakafanana papH yakawanikwa mukusavapo kwebvunzo strip.
Sezvinoratidzwa mufig.7, iyo yakadzika gomba kudzika kwakakonzerwa nePseudomonas aeruginosa biofilm yaive 0.69 µm, iyo yakakura zvakanyanya kupfuura mune abiotic medium (0.02 µm).Izvi zvinobvumirana nepamusoro pe electrochemical data.Pasi pemamiriro akafanana, kudzika kwegomba re0.69 µm kudiki zvakapetwa kagumi pane kukosha kwe9.5 µm kunotsanangurwa ku2205 DSS40.Aya data anoratidza kuti 2707 HDSS inoratidza kuramba kuri nani kuMICs pane 2205 DSS.Izvi hazvishamise sezvo 2707 HDSS ine yakakwira Cr level, iyo inobvumira kureba passivation, inoita kuti Pseudomonas aeruginosa inyanye kuomesesa kuita depassivate, uye inotanga maitiro pasina inokuvadza yechipiri kunaya Pitting41.
Mukupedzisa, MIC pitting yakawanikwa pa2707 HDSS nzvimbo muPseudomonas aeruginosa muto, nepo pitting yakanga isingakoshese mune abiotic media.Iri basa rinoratidza kuti 2707 HDSS ine kuramba kuri nani kuMIC pane 2205 DSS, asi haina kudzivirirwa zvachose kuMIC nekuda kwePseudomonas aeruginosa biofilm.Migumisiro iyi inobatsira pakusarudzwa kwesimbi dzisina tsvina dzakakodzera uye hupenyu hunotarisirwa kunharaunda yegungwa.
Iwo ma2707 HDSS samples akapihwa neChikoro cheMetallurgy, Northeastern University (NEU), Shenyang, China.Iyo yekutanga kuumbwa kwe2707 HDSS inoratidzwa muTebhura 1, iyo yakaongororwa neDhipatimendi reKuongorora uye Kuedza Dhipatimendi reNortheastern University.Mienzaniso yese yakagadziriswa mhinduro yakasimba pa1180 ° C kweawa imwe.Isati yaedzwa corrosion, 2707 HDSS simbi ine nzvimbo yakavhurika ye1 cm2 yakakwenenzverwa kusvika 2000 grit nesilicon carbide sandpaper ndokuzokwenenzverwa ne0.05 µm Al2O3 poda slurry.Mativi uye pasi zvinodzivirirwa nependi inert.Mushure mekuoma, sampuli dzakashambidzwa nemvura isina tsvina yakasvibiswa uye yakasvibiswa ne 75% (v / v) ethanol ye 0.5 h.Dzakazoomeswa nemhepo pasi pe ultraviolet (UV) chiedza kwe 0.5 h isati yashandiswa.
Marine strain Pseudomonas aeruginosa MCCC 1A00099 yakatengwa kubva kuXiamen Marine Culture Collection (MCCC), China.Marine 2216E liquid medium (Qingdao Hope Biotechnology Co., Ltd., Qingdao, China) yakashandiswa kuita tsika Pseudomonas aeruginosa mu250 ml flasks uye 500 ml electrochemical girazi maseru pasi pemamiriro eaerobic pa37°C.Pakati nepakati rine (g/l): 19.45 NaCl, 5.98 MgCl2, 3.24 Na2SO4, 1.8 CaCl2, 0.55 KCl, 0.16 Na2CO3, 0.08 KBr, 0.034 SrCl2, 0.08 2 2 0, 3 Sr0, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 3, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2. 0.008, 0.008 Na4F0H20PO.1.0 mbiriso yakatorwa uye 0.1 iron citrate.Autoclave pa 121 ° C ye 20 min isati yaiswa.Sessile uye masero e planktonic akaverengwa pasi pe microscope yakareruka achishandisa hemocytometer pa 400x magnification.Mamiriro ekutanga eplanktonic P. aeruginosa masero pakarepo mushure mekudzivirira aiva anenge 106 masero / mL.
Electrochemical bvunzo dzakaitwa mukirasi matatu-electrode girazi sero ine yepakati vhoriyamu ye500 ml.Pepa replatinamu uye yakazara calomel electrode (SCE) yakabatana kune reactor kuburikidza neLuggin capillary yakazadzwa nezambuko remunyu uye yakashanda seyakaunta uye rengedzo maelectrodes, zvichiteerana.Kugadzira electrode inoshanda, rubber-coated copper wire yakasungirirwa kune imwe neimwe sampuli uye yakaputirwa ne epoxy, ichisiya inenge 1 cm2 yenzvimbo yepamusoro kune rumwe rutivi rwe electrode inoshanda.Munguva yezviyero zve electrochemical, zvienzaniso zvakaiswa mu 2216E svikiro uye zvakachengetwa pane imwe nguva incubation tembiricha (37 ° C) mumvura yekugeza.OCP, LPR, EIS uye data inogona kusimba polarization yakayerwa pachishandiswa Autolab potentiostat (Reference 600TM, Gamry Instruments, Inc., USA).Miedzo yeLPR yakanyorwa pachiyero chekuongorora che 0.125 mV s-1 mu -5 uye 5 mV renji uye Eocp ine sampling rate ye1 Hz.EIS yakaitwa panzvimbo yakatsiga Eocp ichishandisa magetsi e5 mV ane sinusoid pamusoro pehuwandu hwe 0.01 kusvika 10,000 Hz.Pamberi pekutsvaira kwaigona kuitika, ma electrode aive mumhepo yakavhurika yedunhu kusvika yakagadzikana isina ngura inogona ye42 yasvika.With.Muedzo wega wega wakadzokororwa katatu pamwe uye pasina Pseudomonas aeruginosa.
Masamples ekuongorora metallographic akakwenenzverwa ne 2000 grit wet SiC bepa ndokuzokwenenzverwa ne 0.05 µm Al2O3 poda slurry yekutarisa kwemaziso.Metallographic analysis yakaitwa uchishandisa optical microscope.Muenzaniso wakaiswa ne 10 wt% potassium hydroxide solution43.
Mushure mekuvhara, geza katatu ne phosphate buffered saline (PBS) (pH 7.4 ± 0.2) uye wozogadzirisa ne 2.5% (v / v) glutaraldehyde kwemaawa gumi kugadzirisa biofilm.Kutevera kupera kwemvura ne ethanol mune yakatevedzana yakatevedzana (50%, 60%, 70%, 80%, 90%, 95% uye 100% nehuwandu) isati yaoma mhepo.Pakupedzisira, firimu regoridhe rakaputirwa pamusoro peiyo sampuli kupa conductivity yeSEM44 yekutarisa.Mifananidzo yeSEM yakanangana nenzvimbo ine masero akanyanya kusimbiswa P. aeruginosa pamusoro pemuenzaniso wega wega.EMF ongororo yakaitwa kuti ione zvinhu zvemakemikari.Kuyera kudzika kwegomba, Zeiss confocal laser scanning microscope (CLSM) (LSM 710, Zeiss, Germany) yakashandiswa.Kuona makomba ekuora pasi pe biofilm, sampu yebvunzo yakatanga kucheneswa zvinoenderana neChinese National Standard (CNS) GB/T4334.4-2000 kubvisa zvigadzirwa zvekuora uye biofilm kubva pamusoro peyedzo sampuli.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 Surface Analysis System, Thermo VG, USA) ongororo uchishandisa monochromatic X-ray source (Al Kα mutsetse une simba re1500 eV uye simba re150 W) musimba rakasiyana siyana rinosunga. 0 pazasi pezvakajairwa mamiriro e -1350 eV.Rekodha yakakwirira resolution spectra uchishandisa 50 eV pass simba uye 0.2 eV nhanho saizi.
Bvisa sampu yakavharirwa woigeza zvinyoro nyoro nePBS (pH 7.4 ± 0.2) ye15 s45.Kuti uone kushanda kwebhakitiriya kweiyo biofilm pamuenzaniso, iyo biofilm yakasvibiswa uchishandisa LIVE/DEAD BacLight Bacterial Viability Kit (Invitrogen, Eugene, OR, USA).Iyo kit ine maviri efluorescent dhayi: SYTO-9 yegirini fluorescent dhayi uye propidium iodide (PI) tsvuku fluorescent dhayi.MuCLSM, fluorescent green and red dots inomiririra masero mupenyu uye akafa, zvichiteerana.Pakusvibisa, isa 1 ml yemusanganiswa une 3 µl yeSYTO-9 uye 3 µl yePI solution patembiricha yekamuri (23°C) murima kwemaminetsi makumi maviri.Mushure meizvozvo, masampula akasvibiswa akacherechedzwa pawavelengths maviri (488 nm yemasero mhenyu uye 559 nm yemasero akafa) uchishandisa Nikon CLSM apparatus (C2 Plus, Nikon, Japan).Edza iyo biofilm ukobvu mune 3-D scanning mode.
Matauriro echinyorwa ichi: Li, H. et al.Mhedzisiro yePseudomonas aeruginosa marine biofilm pane microbial corrosion ye2707 super duplex stainless steel.sainzi.House 6, 20190;doi:10.1038/srep20190 (2016).
Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Stress corrosion cracking yeLDX 2101 duplex stainless steel mu chloride solutions pamberi pe thiosulfate.ngura.sainzi.80, 205–212 (2014).
Kim, ST, Jang, SH, Lee, IS uye Park, YS Mhedzisiro yemhinduro yekupisa kupisa uye nitrogen mukudzivirira gasi pagomba rekudzivirira kwegomba re super duplex Stainless steel welds.ngura.sainzi.53, 1939–1947 (2011).
Shi, X., Avchi, R., Geyser, M. uye Lewandowski, Z. Chidzidzo chekuenzanisa chemakemikari ye microbial uye electrochemical pitting mu 316L simbi isina tsvina.ngura.sainzi.45, 2577–2595 (2003).
Luo H., Dong KF, Li HG uye Xiao K. Electrochemical maitiro e2205 duplex Stainless simbi mune alkaline mhinduro pane akasiyana pH kukosha pamberi pekloridi.electrochemistry.Journal.64, 211–220 (2012).
Nguva yekutumira: Jan-09-2023