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Microbial corrosion (MIC) idambudziko rakakomba mumaindasitiri akawanda sezvo rinogona kukonzera kurasikirwa kukuru kwehupfumi.2707 super duplex stainless steel (2707 HDSS) yakashandiswa munzvimbo dzegungwa nekuda kwekusagadzikana kwemakemikari.Zvisinei, kuramba kwayo kuMIC hakuna kumboratidzwa.Muchidzidzo ichi, maitiro eMIC e2707 aerobics akaitwa ne2707 HDSS. .Kuongororwa kweElectrochemical kwakaratidza kuti pamberi pePseudomonas aeruginosa biofilm mu2216E yepakati, pakanga paine shanduko yakanaka mukuora kunogona kuita uye kuwedzera kwekuora kwezvino density.X-ray photoelectron spectroscopy (XPS) kuongororwa kwakaratidza kuderera kweCr content pamusoro peiyo specimen iri pasi peiyo biofilmrug yakadzama yakaratidza iyo biofilm yakadzama yakaratidza kudzika kwepifilmrug yakaratidza iyo biofilm yakadzama. ye 0.69 μm mumazuva e14 ekudzivirira. Kunyange zvazvo izvi zvishoma, zvinoratidza kuti 2707 HDSS haina kunyatsodzivirira kuMIC yeP. aeruginosa biofilms.
Duplex Stainless steels (DSS) inoshandiswa zvakanyanya mumabhizimisi akasiyana-siyana nokuda kwekubatanidzwa kwavo kwakanakisisa kwemaitiro ekugadzirisa zvinhu uye kusagadzikana kwekuora1,2.Zvisinei, pitting yemunharaunda ichiri kuitika uye inokanganisa kuvimbika kwesimbi iyi3,4.DSS haigoni kupikisa microbial corrosion (MIC) 5,6.Pasinei nehupamhi hwehurefu hwekushandiswa kweDSS husati huripo hurefu hwekushandiswa kweDSS kushandiswa kwekushandiswa kweDSS kwenguva refu. .Izvi zvinoreva kuti zvinhu zvinodhura zvakanyanya zvine corrosion resistance inodiwa.Jeon et al7 vakawana kuti kunyange super duplex Stainless steels (SDSS) vane zvimwe zvinogumira maererano necorrosion resistance.Saka, super duplex Stainless steels (HDSS) ine high corrosion resistance inodiwa mune mamwe maapplication.Izvi zvakaita kuti pave nekugadzirwa kweHDSS yakanyanya kusanganiswa.
Kurwisana kwekuora kweDSS kunoenderana nehuwandu hwema alpha uye gamma phases uye Cr, Mo uye W yakapera nzvimbo 8, 9, 10 yakatarisana nechikamu chechipiri.HDSS ine zvinyorwa zvepamusoro zveCr, Mo neN11, saka ine yakanakisa kusarura kwekudzivirira uye kukosha kwepamusoro (45-50) Pitting Resistance Equitance (PREN% + 3% Equitance + Cr + Cr + 3%. 0.5 wt% W) + 16 wt% N12.Iyo yakanakisa corrosion resistance inotsamira pakuumbwa kwakaenzana kuine anenge 50% ferrite (α) uye 50% austenite (γ) zvikamu, HDSS ine zviri nani mechanical properties uye yakakwirira kupikisa kudarika DSS13 yakajairwa.Chloride corrosion properties.Iyo yakagadziridzwa yekudzivirira kusvibiswa kunowedzera kushandiswa kweHDSS munzvimbo dzakawanda dzinopisa chloride, dzakadai semamiriro egungwa.
MICs idambudziko guru mumaindasitiri akawanda akadai semafuta uye gasi uye zvishandiswa zvemvura14.MIC inobata 20% yezvose zvinokanganisa kuparara15.MIC is bioelectrochemical corrosion inogona kuonekwa munzvimbo dzakawanda.Biofilms inoumba panzvimbo yesimbi inoshandura mamiriro e electrochemical, nokudaro inokanganisa corrosion corrosion process. s corrode metals kuwana simba rinotsigira kurarama17.Zvidzidzo zveMIC zvenguva pfupi yapfuura zvakaratidza kuti EET (extracellular electron transfer) ndiyo inoderedza chiyero muMIC inokonzerwa ne electrogenic microorganisms.Zhang et al.18 yakaratidza kuti varevereri vemagetsi vanomhanyisa kuendesa maerekitironi pakati peDesulfovibrio sessificans masero uye 304 simbi isina tsvina, zvichiita kuti kurwiswe kwakanyanya kweMIC.Enning et al.19 uye Venzlaff et al.20 yakaratidza kuti corrosive sulfate-reducing bacteria (SRB) biofilms inogona kutora maerekitironi zvakananga kubva kusimbi substrates, zvichikonzera kukora kwegomba.
DSS inozivikanwa kuti inobatwa neMIC munzvimbo dzine SRB, iron-reducing bacteria (IRB), etc. 21 .Mabhakitiriya aya anokonzera pitting yenzvimbo paDSS pasi pe biofilms22,23.Kusiyana neDSS, MIC yeHDSS24 haina kuzivikanwa.
Pseudomonas aeruginosa is a gram-negative motile-shaped rod bacterium iyo inoparadzirwa zvakanyanya muzvisikwa25.Pseudomonas aeruginosa iboka guru rehutachiona mumhepo yegungwa, zvichiita kuti MIC iite simbi.Pseudomonas inobatanidzwa zvakanyanya mukugadzirisa corrosion uye inozivikanwa semapionari e-biohafilmt .28 uye Yuan et al.29 yakaratidza kuti Pseudomonas aeruginosa ine tsika yekuwedzera kukora kwesimbi yakapfava uye alloys munzvimbo dzine mvura.
Chinangwa chikuru chebasa iri chaive chekuongorora hunhu hweMIC hwe2707 HDSS hwakakonzerwa nebhakteriya remugungwa rinonzi Pseudomonas aeruginosa richishandisa nzira dze electrochemical, maitiro ekuongorora pamusoro uye kuororwa kwechigadzirwa.Zvidzidzo zveElectrochemical zvinosanganisira Open Circuit Potential (OCP), Linear Polarization Resistance (LPR), Electrochemical Resistance (LPR) uye Electrochemical Resistance (LPR) yakaitwa kuti iongorore maitiro eMIC e2707 HDSS.Energy dispersive spectrometer (EDS) kuongororwa kwakaitwa kuti uwane zvinhu zvemakemikari panzvimbo yakasvibiswa.Kuwedzera, X-ray photoelectron spectroscopy (XPS) kuongororwa yakashandiswa kuona kugadzikana kweoxide firimu passivation pasi pesimba remhepo yegungwa ine Pseudomonas pieruginosa yakayerwa pasi pesmcl scanning laser.
Tafura 1 inoronga kuumbwa kwemakemikari e2507 HDST.CABLE 2 inoratidza kuti simba reAustence yeSpolenti
Figure 2a inoratidza yakavhurika redunhu zvingangoitika (Eocp) maringe nekufumurwa nguva data ye2707 HDSS muabiotic 2216E svikiro uye P. aeruginosa muto kwemazuva 14 pa 37 °C.Inoratidza kuti yakakura uye yakakosha shanduko muEocp inoitika mukati memaawa makumi maviri nemana ekutanga.Iyo Eocp yakakosha pa 1 mV 5 uye 1 m VH yakatenderedza 1 mV ​​makesi maviri - 1 mV yakabva yadonha zvakanyanya, ichisvika -477 mV (vs. SCE) uye -236 mV (vs. SCE) yeabiotic sample uye P, zvichiteerana ).Pseudomonas aeruginosa makuponi, zvichiteerana.Mushure memaawa makumi maviri nemana, kukosha kweEocp kwe2707 HDSS yeP. aeruginosa yakanga yakadzikama pa -228 mV (vs. SCE), nepo kukosha kunoenderana neasiri-biological samples angangoita -442 mV (vs. S.SCE yakaderera muPorugino muE.
Electrochemical test ye2707 HDSS samples mune abiotic medium uye Pseudomonas aeruginosa muto pa37 °C:
(a) Eocp sebasa renguva yekufumurwa, (b) polarization curves pazuva 14, (c) Rp sebasa rekuratidzwa nguva uye (d) icorr sebasa rekuratidzwa nguva.
Tafura 3 inonyora electrochemical corrosion parameter values ​​​​ye2707 HDSS samples yakazarurirwa kune abiotic medium uye Pseudomonas aeruginosa inoculated medium kwemazuva 14. Tangents yeanodic uye cathodic curves yakabudiswa kuti isvike pamiganhu inobereka corrosion current density (corrαcorsion) uye corrosion yezvino ( lα corrrosion ) uye corrosion yezvino. βc) zvinoenderana neyakajairwa nzira30,31.
Sezvinoratidzwa mumufananidzo 2b, kushanduka kwepamusoro kweP. aeruginosa curve kwakaguma nekuwedzera kweEcorr kana ichienzaniswa neabiotic curve.Ikorr kukosha, iyo yakaenzana nehuwandu hwekuora, yakawedzera kusvika ku 0.328 μA cm-2 muPseudomonas aeruginosa isingasviki sampuli μ Aeruginosa, μ Aeruginosa sampuli 0 μA-7 kanomwe.
LPR is a classic non-destructive electrochemical method for quick corrosion analysis.Yakashandiswawo kudzidza MIC32.Figure 2c inoratidza polarization resistance (Rp) sebasa rekufumurwa nguva.A high Rp value inoreva kushomeka kwecorrosion.Mukati memaawa makumi maviri nemana ekutanga, Rp ye2707 HDSS yakasvika pa5 kbiotic 9 cm29cm uye 5 kbiotic 9 cm29cm. nokuda kwePseudomonas aeruginosa samples.Mufananidzo 2c unoratidzawo kuti kukosha kweRp kwakaderera nokukurumidza mushure mezuva rimwe ndokuzoramba kusingashanduki kwemazuva anotevera 13. Rp kukosha kwePseudomonas aeruginosa sampuli inenge 40 kΩ cm2, iyo yakaderera zvikuru kupfuura 450 kΩ-cm2 sampuli ye-nonbiological value.
Iko icorr kukosha kwakaenzana neuniform corrosion rate.Kukosha kwayo kunogona kuverengwa kubva kune inotevera Stern-Geary equation,
Kutevera Zou et al.33, kukosha kwakajairika kweTafel slope B mubasa iri yaifungidzirwa kuva 26 mV/dec. Mufananidzo 2d unoratidza kuti icorr yemuenzaniso usiri webhayoloji 2707 yakaramba yakagadzikana, nepo P. aeruginosa sampuli yakachinja zvikuru mushure memaawa makumi maviri nemana ekutanga. Iyo icorr yemaitiro epamusoro-soro emhando dzepamusoro-soro dzemasamples e-non-biological 2707 yakaramba yakagadzikana. ological controls.Maitiro aya anofambirana nemhedzisiro yepolarization resistance.
EIS ndiyo imwe nzira isingagadzirisike inoshandiswa kuratidza maitiro emagetsi panzvimbo dzakaora.Impedance spectra uye yakaverengerwa capacitance kukosha kwezvienzaniso zvakafumurwa kune abiotic media uye Pseudomonas aeruginosa mhinduro, Rb kuramba kwepasirefi firimu/biofilm yakaumbwa pamusoro peiyo specimen, Rct charger kufambisa magetsi kuramba, Cdl caji yekutamisa magetsi (Cdl capetant) Cdl Castal (Cdl caji) CPE) parameters.Iyi mitemo yakaongororwa zvakare nekukodzera data uchishandisa muenzaniso wakaenzana wedunhu (EEC).
Mufananidzo 3 unoratidza maNyquist plots (a nab) uye Bode plots (a' and b') of 2707 HDSS samples in abiotic medium and P. aeruginosa broth for different incubation times.Kureba kweNyquist ring kunodzikira pamberi pePseudomonas aeruginosa.The Bode 3bed in the total of the fignition incubation. nguva yekuzorora nguva dzose inogona kupiwa nechikamu chechikamu.Mufananidzo 4 unoratidza monolayer (a) uye bilayer (b) zvivako zvemuviri zvakagadzirirwa uye maEEC anoenderana nawo.CPE inopinzwa mumuenzaniso weEEC.Kubvuma kwayo uye impedance inoratidzwa sezvinotevera:
Mhando mbiri dzemuviri uye matunhu akaenzana akaenzana ekukodzera iyo impedance spectrum ye2707 HDSS specimen:
apo Y0 ndiyo hukuru hweCPE, j inhamba yekufungidzira kana (-1) 1 / 2, ω ndiyo inotenderera yeangular, uye n ndiyo CPE simba index zvishoma kudarika unity35. The inverse yechaji yekuendesa kushorwa (kureva 1 / Rct) inofananidzwa nehuwandu hwekuora.Smaller Rct inoreva kukurumidza kuora kwekutengesa kwemazuva 14, Aftuerba ye27. eruginosa samples yakasvika 32 kΩ cm2, idiki kwazvo pane iyo 489 kΩ cm2 yeasiri-biological samples (Tafura 4).
Mifananidzo yeCLSM nemifananidzo yeSEM ​​muMufananidzo 5 inoratidza zvakajeka kuti kuvharidzirwa kwebiofilm pamusoro pe2707 HDSS muenzaniso mushure memazuva 7 yakaoma.Zvisinei, mushure memazuva gumi nemana, kuvharwa kwebiofilm kwakanga kusina uye mamwe masero akafa akaonekwa.Tafura 5 inoratidza huwandu hwebiofilm pa 2707 HDSS specimens mushure memazuva makumi mana. kubva ku23.4 μm mushure memazuva manomwe kusvika ku18.9 μm mushure memazuva 14. Ivhareji yebiofilm yakakura yakasimbisawo maitiro aya.Yakaderera kubva ku22.2 ± 0.7 μm mushure memazuva manomwe kusvika ku17.8 ± 1.0 μm mushure memazuva gumi nemana.
(a) 3-D CLSM mufananidzo mushure memazuva manomwe, (b) 3-D CLSM mufananidzo mushure memazuva gumi nemana, (c) SEM mufananidzo mushure memazuva manomwe uye (d) SEM mufananidzo mushure memazuva gumi nemana.
EDS yakaratidza zvinhu zvemakemikari mu biofilms uye corrosion zvigadzirwa pamasampuli akazarurwa kuP. aeruginosa kwemazuva 14. Mufananidzo 6 unoratidza kuti zvinyorwa zveC, N, O, uye P mu biofilms uye zvigadzirwa zvekuora zvakanyanya kudarika izvo zviri musimbi isina chinhu, nokuti zvinhu izvi zvinosanganiswa ne biofilms uye metabolites yavo.Microbes yeC, N, O, uye P muzvinyorwa zvebiofilms uye corrosion zvigadzirwa zvakakwirira zvikuru kupfuura izvo zviri musimbi dzisina chinhu, nokuti zvinhu izvi zvinosanganiswa ne biofilms uye metabolites yavo.Microbes yeC, C, O, uye P mu biofilms uye zvigadzirwa zvekuora zvakanyanya kudarika izvo zviri musimbi isina chinhu, nokuti zvinhu izvi zvinosanganiswa ne biofilms uye metabolites. rosion zvigadzirwa pamusoro pezvienzaniso zvinoratidza kuti simbi matrix yakarasika zvinhu nekuda kwekuora.
Mushure memazuva gumi nemana, gomba uye pasina P. aeruginosa yakaonekwa mu 2216E medium. Pamberi pekuputira, nzvimbo yemuenzaniso yakanga yakatsetseka uye isina kukanganisa (Fig. 7a) .Mushure mekuvhara uye kubviswa kwezvigadzirwa zvebiofilm uye corrosion, makomba akadzika pamusoro pezvienzaniso zvakaratidzwa pasi pe7 pigus yakawanikwa pasi pe7 pigus yakawanikwa pasi pe 7 pigu. -biological control samples (yakanyanya gomba kudzika 0.02 μm). Iyo yakanyanya gomba kudzika kwakakonzerwa nePseudomonas aeruginosa yaive 0.52 μm mushure memazuva manomwe uye 0.69 μm mushure memazuva gumi nemana, zvichibva paavhareji yegomba kudzika kwemasamples e3 (10 yakanyanya gomba kudzika kwakadzika maitiro) 2 ± 2 ± 0 yakasarudzwa 2 ± 00. 0.15 μm, zvichiteerana (Table 5) .Idzi gomba dzakadzika tsika idiki asi dzakakosha.
(a) Tisati tafumurwa, (b) Mazuva gumi nemana mune abiotic medium uye (c) mazuva gumi nemana muPseudomonas aeruginosa muto.
Mufananidzo 8 unoratidza XPS spectra yemhando dzakasiyana dzemasampuli, uye makemikari akaongororwa panzvimbo imwe neimwe anopfupikiswa muTebhu 6.MuTebhenekeri 6, maatomu ezvikamu zveFe neCr pamberi peP. aeruginosa (samples A uye B) akanga akaderera zvikuru pane ayo asiri e-biological control samples (samples sampuli yeC-core P. spectral curve yakaiswa kune ina peak zvikamu zvine simba rinosunga (BE) kukosha kwe574.4, 576.6, 578.3 uye 586.8 eV, iyo inogona kunzi ndeye Cr, Cr2O3, CrO3 uye Cr (OH) 3, zvichiteerana (Fig. mapikisi makuru maviri eCr (573.80 eV yeBE) uye Cr2O3 (575.90 eV yeBE) muFig. 9c uye d, maererano.Musiyano unoshamisa pakati peabiotic uye P. aeruginosa samples kwaiva kuvapo kweCr6 + uye chikamu chepamusoro cheCr (OH) 5)68 ye biofilm66 (BE) 6 (BE)
Iyo yakafara XPS spectra pamusoro peiyo 2707 HDSS specimen mune maviri midhiya mazuva manomwe nemazuva gumi nemana, zvichiteerana.
(a) 7 mazuva ekusangana neP. aeruginosa, (b) mazuva gumi nemana ekusangana neP. aeruginosa, (c) mazuva manomwe muabiotic medium uye (d) mazuva gumi nemana mune abiotic medium.
HDSS inoratidzira mazinga akakwira ekuramba kwecorrosion munzvimbo zhinji.Kim et al.2 yakashuma kuti UNS S32707 HDSS yakatsanangurwa seDSS yakanyanya kusanganiswa ine PREN inopfuura 45. The PREN kukosha kwe2707 HDSS specimen mubasa iri yaiva 49.Izvi zvinokonzerwa nehuwandu hwechromium uye high molybdenum neNi mazinga, ayo anobatsira mumamiriro ezvinhu ane acidic uye zvakanaka chloride-yakasununguka-yakagadziriswa microdefect. kugadzikana kwemaitiro uye kusagadzikana kwekuora.Zvisinei, pasinei nekupikisa kwakanakisisa kwemakemikari, ruzivo rwekuedza mubasa iri rinoratidza kuti 2707 HDSS haina kudzivirirwa zvachose kuMIC yeP. aeruginosa biofilms.
Electrochemical results yakaratidza kuti corrosion rate ye2707 HDSS muP. aeruginosa muto yakawedzera zvakanyanya mushure memazuva gumi nemana kana ichienzaniswa neasiri-biological medium.Mumufananidzo 2a, kuderedzwa kweEocp kwakaonekwa mune zvose abiotic medium uye P. aeruginosa muto munguva yekutanga kwemaawa 24. Mushure mokunge yapera, iyo yakavhara iyo biocmen inova yakavharidzirwa pamusoro pepamusoro, iyo yakavharidzirwa inova yakavharidzirwa pamusoro peEocp. 6.Zvisinei, chiyero cheEocp yehupenyu chaive chakakwirira kudarika cheEocp isiri yehupenyu.Pane chikonzero chekutenda kuti kusiyana uku kunokonzerwa neP. aeruginosa biofilm formation.Mumufananidzo 2d, pamberi peP. aeruginosa, iyo icorr kukosha kwe2707 HDSS yakasvika 0.627 yakakwira yekuraira kweiyo magniA μ. 63 μA cm-2), iyo yaienderana neRct value yakayerwa neEIS.Pamazuva mashomanana okutanga, impedance values ​​muP. aeruginosa broth yakawedzera nekuda kwekubatanidzwa kweP. Nokudaro, kupikisa kwekuora kwakaderera nekufamba kwenguva, uye kusungirirwa kweP. aeruginosa kwakakonzera kuparara kwenzvimbo.Maitirwo ezvinyorwa zveabiotic akanga akasiyana.Kurwisana kwekuora kweasiri-biological control kwakakwira zvakanyanya kudarika kukosha kwaienderana kwemasamples akafumurwa kuP. yakanga iri 15 nguva yeRct value (32 kΩ cm2) pamberi peP. aeruginosa. Nokudaro, 2707 HDSS ine hutano hwakanaka hwekuora munzvimbo isina utachiona, asi haigoni kupikisa MIC kurwisa neP. aeruginosa biofilms.
Migumisiro iyi inogonawo kuonekwa kubva kune polarization curves muFig. 2b.Anodic branching inonzi inonzi Pseudomonas aeruginosa biofilm formation uye metal oxidation reactions.Panguva imwe chete iyo cathodic reaction ndiyo kuderedzwa kweokisijeni.Kuvapo kweP. aeruginosa kwakawedzera zvakanyanya kurongeka kwepamusoro kurongeka kwepamusoro pehuwandu hwemagnitu. ruginosa biofilm inowedzera kuparara kwenzvimbo ye2707 HDSS.Yuan et al29 vakawana kuti corrosion current density ye70/30 Cu-Ni alloy yakawedzera pasi pedambudziko reP. c biofilms inogonawo kuva neokisijeni shoma pasi payo.Saka, kukundikana kudzorerazve simbi yesimbi neoksijeni inogona kuva chinhu chinokonzera kuMIC mubasa iri.
Dickinson et al.38 yakaratidza kuti zviyero zvemakemikari uye electrochemical reactions zvinogona kuchinjwa zvakananga nebasa remagetsi ehutachiona hwesessile pamusoro pemuenzaniso uye chimiro chezvigadzirwa zvekuora.Sezvinoratidzwa mumufananidzo 5 uye Tafura 5, zvose sero nhamba uye biofilm yakakura yakaderera mushure memazuva 14. Izvi zvinogona kutsanangurwa zvinonzwisisika kuti mushure memazuva gumi nemana ekupedzisira kwe270SS yakafa pamusana pemasero e270 akaparara muHD70. iyo 2216E yepakati kana kubudiswa kweiyoni yesimbi ine chepfu kubva ku2707 HDSS matrix. Uku ndiko kudzikisira kwebhechi kuedza.
Mune basa iri, iyo P. aeruginosa biofilm yakakurudzira kuderedzwa kwenzvimbo yeCr uye Fe pasi peiyo biofilm pa2707 HDSS pamusoro (Fig. 6) .MuTebhenekeri 6, kuderedzwa kweFe uye Cr mumuenzaniso D yakaenzaniswa nemuenzaniso C, zvichiratidza kuti yakanyungudutswa Fe neCr yakakonzerwa neP. .Iyo ine 17700 ppm Cl-, iyo inofananidzwa neyo inowanikwa mumvura yegungwa yakasikwa.Kuvapo kwe17700 ppm Cl- ndiyo yaiva chikonzero chikuru chekuderedzwa kweCr mu7- uye 14-day abiotic samples yakaongororwa neXPS. Inofananidzwa neP. 2707 HDSS munzvimbo dzeabiotic.Mufananidzo 9 unoratidza kuvapo kweCr6 + mufirimu yepasisiti.Inogona kunge yakabatanidzwa mukubviswa kweCr kubva panzvimbo dzesimbi neP. aeruginosa biofilms, sezvakataurwa naChen naClayton.
Nekuda kwekukura kwebhakitiriya, iyo pH yakakosha yepakati isati yarimwa uye mushure mekurima yaive 7.4 uye 8.2, zvichiteerana. Naizvozvo, pasi peP. aeruginosa biofilm, organic acid corrosion haigone kuve chinhu chinokonzera basa iri nekuda kweiyo pH yakakwira mukati mehuwandu. Iyo pH yeasiri-biology haina kuchinja zvakanyanya panguva yekutanga 7. 4-zuva rekuedza nguva.Kuwedzera kwepH mumhepo inoculation mushure mekugadzirisa kwakakonzerwa nekushanda kwemasabolism eP. aeruginosa uye yakawanikwa iine maitiro akafanana papH mukushayikwa kwekuedzwa kwemavara.
Sezvinoratidzwa muMufananidzo 7, iyo yakadzika gomba yakadzika yakakonzerwa neP. aeruginosa biofilm yaiva 0.69 μm, iyo yakanga yakakura kudarika iyo yeabiotic medium (0.02 μm) .Izvi zvinopindirana nemashoko e electrochemical anotsanangurwa pamusoro apa.Iyo 0.69 μm gomba rakadzika rinopfuura kagumi duku kudarika μm 205 kukosha kweDSS yakashuma pasi peDSS 925. 707 HDSS inoratidzira nani MIC kuramba kana ichienzaniswa ne2205 DSS. Izvi hazvifanirwe kushamisa, sezvo 2707 HDSS ine yakakwirira chromium content, ichipa kwenguva yakareba passivation, nokuda kwakaringana chikamu chimiro pasina inokuvadza yechipiri precipitates, zvichiita kuti zviomere P. aeruginosa kuti depassivate uye kutanga pfungwa eclipse.
Mukupedzisa, MIC pitting yakawanikwa pamusoro pe2707 HDSS muP. aeruginosa muto kana ichienzaniswa negomba risingakoshi mune abiotic media.Iri basa rinoratidza kuti 2707 HDSS ine nani MIC kushorwa kupfuura 2205 DSS, asi haina kunyatsodzivirira kuMIC nekuda kweP.
Ikoponi ye2707 HDSS inopiwa neSchool of Metallurgy yeNortheastern University (NEU) muShenyang, China.The elemental composition of 2707 HDSS inoratidzwa muTebhurari 1, iyo yakaongororwa neNEU Materials Analysis uye Testing Department.All samples were solution yakabatwa pa1180 °C kune 2707 HDSS pamusoro peawa 1 corped yakazarurwa pamusoro peawa 1 corped SS. nzvimbo ye1 cm2 yakakwenenzverwa kusvika 2000 grit nesilicon carbide bepa uye zvakare kukwenenzverwa ne 0.05 μm Al2O3 poda suspension. Mativi nepasi anodzivirirwa nependi inert. Mushure mekuoma, zvienzaniso zvakasukwa nemvura isina tsvina yakasvibiswa uye yakasvibiswa ne75 ultraviolet . V) chiedza kwemaawa 0.5 isati yashandiswa.
Marine Pseudomson Agagunosa MCCC 1A000 Litting kubva Xiamen Marine Tsika Center (McCC) O, China) 0 mbiriso inobvisa uye 0.1 ferric citrate.auto citrate
Electrochemical tests yakaitwa mu classic three-electrode glass cell ine medium volume ye 500 ml. A platinum sheet uye saturated calomel electrode (SCE) yakabatanidzwa kune reactor kuburikidza neLuggin capillaries yakazadzwa nemabhiriji emunyu, achishanda se-counter uye mareferensi emagetsi, zvichiteerana.Kuita maelectrodes anoshanda, rabha-yakavharidzirwa yakavharwa, yakavharwa nerabha-yakavharwa, yakavharwa ne-1 cm yakavharwa nemhangura imwe neimwe yemhangura. -sided surface area for the working electrode.Pakati pezviyero zve electrochemical, sampuli dzakaiswa mu 2216E svikiro uye dzakachengetwa panguva yekushisa kwekudzivirira nguva dzose (37 ° C) mumvura yekugezera mvura.OCP, LPR, EIS uye data inogona kushanduka yepolarization yakayerwa uchishandisa Autolab potentiostat (Reference 600TM, Gamry.R.Inc chiyero cheU.VRR scaned, Instruments, Inc., Instruments, USA). s-1 pamusoro pehuwandu hwe -5 uye 5 mV neEocp uye sampling frequency ye1 Hz.EIS yakaitwa ne sine wave muhuwandu hwehuwandu hwe 0.01 kusvika ku10,000 Hz uchishandisa 5 mV inoshandiswa magetsi panzvimbo yakadzikama Eocp. Pamberi pekutsvaira kunogona kuitika, ma electrodes akanga ari muvhuro-inotenderera kukosha kweporization yakasvika pa 0cor . 2 kusvika 1.5 V vs. Eocp pachiyero che 0.166 mV / s. Muedzo wega wega wakadzokororwa 3 nguva uye pasina P. aeruginosa.
Mienzaniso yekuongorora metallographic yakakwenenzverwa ne 2000 grit wet SiC bepa uyezve yakakwenenzverwa ne 0.05 μm Al2O3 powder suspension for optical observation.Metallographic analysis yakaitwa pachishandiswa optical microscope.Zvienzaniso zvakaiswa 10 wt.% potassium 43 hydroxide solution.
Mushure mekuiswa, sampuli dzakashambidzwa katatu ne phosphate-buffered saline (PBS) solution (pH 7.4 ± 0.2) uye yakazogadziriswa ne 2.5% (v/v) glutaraldehyde kwemaawa gumi kugadzirisa biofilms. Yakazopera mvura ine graded series (50%, 5%, 9%, 7% , 50%, 9%, 70% , 50%, 9%, 7% , 6% , 50%, 9%, 70% , 6% , 50%, 9%, 6% , 6% , 00% v / v) ye ethanol isati yaoma mhepo.Pakupedzisira, nzvimbo yemuenzaniso inoputirwa nefirimu yegoridhe kuti ipe conductivity yekuona kweSEM.Mifananidzo yeSEM ​​yakanga yakatarisa pane mavara ane sessile P. aeruginosa masero pamusoro pemuenzaniso wega wega.Ita EDS kuongorora kuti uwane zvinhu zvemakemikari.ALSMMS SMFoickan Zescope, Germany Zescopic Zeiss SMZ1 Germany yakashandiswa kuyera kudzika kwegomba.Kuitira kutarisa makomba ekuora pasi pebiofilm, chidimbu chekuedza chakatanga kucheneswa maererano neChinese National Standard (CNS) GB/T4334.4-2000 kubvisa zvigadzirwa zvekuora uye biofilm pamusoro pechikamu chekuyedza.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 surface analysis system, Thermo VG, USA) ongororo yakaitwa pachishandiswa monochromatic X-ray source (aluminium Kα line pa1500 eV simba uye 150 W simba) pamusoro pesimba rakafara rinosunga 0 pasi pemamiriro akajairwa -1350 eV.High-resolution yakarekodhwa 0 nhanho yeV eV uye saizi ye50.
Mienzaniso yakavharidzirwa yakabviswa uye yakashambidzwa zvinyoro-nyoro nePBS (pH 7.4 ± 0.2) ye15 s45. Kuti uone kushanda kwebhakitiriya yebiofilms pazvienzaniso, iyo biofilms yakasvibiswa uchishandisa LIVE / DEAD BacLight Bacterial Viability Kit (Invitrogen, Eugene fluorescent, Eugene fluorescent, USA fluorescent). SYTO-9 dhayi uye dzvuku fluorescent propidium iodide (PI) dhayi.Pasi peCLSM, madotsi ane fluorescent girini uye tsvuku anomiririra mhenyu uye akafa maseru, zvichiteerana.Kusvibisa, 1 ml musanganiswa une 3 μl SYTO-9 uye 3 μl PI mhinduro yakavharirwa kwemaminetsi makumi maviri eC20 yakavharwa pamhepo ye23 yakasviba tembiricha mu23 yakasviba tembiricha. (488 nm yemasero mhenyu uye 559 nm yemasero akafa) uchishandisa Nikon CLSM muchina (C2 Plus, Nikon, Japan) .Biofilm ukobvu hwakayerwa mu 3-D scanning mode.
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