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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 kwekushomeka kwayo kwemakemikari.Zvisinei, kuramba kwayo kuMIC hakuna kumboratidzwa.Muchidzidzo ichi, maitiro eMIC e2707 aerobics aerobics 2707 HDSS aeruginosa yakaongororwa.Kuongororwa kweElectrochemical kwakaratidza kuti pamberi pePseudomonas aeruginosa biofilm mu 2216E yepakati, pakanga pane kuchinja kwakanaka mukukwanisa kwekuora uye kuwedzera kwekuora kwezvino. aeruginosa biofilm yakagadzira hurefu hwegomba rakadzika re 0.69 μm mumazuva gumi nemana ekuputira.Kunyange zvazvo izvi zviduku, zvinoratidza kuti 2707 HDSS haina kunyatsodzivirira kuMIC yeP. aeruginosa biofilms.
Duplex Stainless Steels (DSS) inoshandiswa zvakanyanya mumaindasitiri akasiyana-siyana ehukama hwezvakanaka kukwana kuti ishandiswe 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.Naizvozvo, super duplex Stainless steels (HDSS) ine corrosion resistance inodiwa mune mamwe maapplication.Izvi zvakaita kuti pave nekugadzirwa kweHDSS yakanyanya alloyed.
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 uye N11, saka ine yakanakisa kusarura kwekudzivirira uye kukosha kwepamusoro (45-50) Pitting Resistance Equitance (3%) neCr 3% Equistance (3%). (wt.% Mo + 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 yakajairika. 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 ndeye bioelectrochemical corrosion inogona kuonekwa munzvimbo dzakawanda.Mafirimu ehupenyu anoumba panzvimbo dzesimbi anoshandura mamiriro e electrochemical, nokudaro anokanganisa maitiro e-corrosion anotenda kuti MIC inokonzerwa zvakanyanya. biofilms.Electrogenic microorganisms inoparadza simbi kuti iwane simba rinochengetedza kuti rirarame17.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 .Aya mabhakitiriya anokonzera pitting munzvimbo yeDSS pasi pe biofilms22,23.Kusiyana neDSS, MIC yeHDSS24 haina kuzivikanwa.
Pseudomonas aeruginosa is gram-negative motile-shaped rod bacterium iyo inoparadzirwa zvakanyanya muzvisikwa25.Pseudomonas aeruginosa iboka guru rehutachiona mumhoteredzo 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), Electrochemical Resistance (LPR) Dynamic Polarization yakaitwa kuti iongorore maitiro eMIC e2707 HDSS.Energy dispersive spectrometer (EDS) kuongororwa kwakaitwa kuti kuwane zvinhu zvemakemikari panzvimbo yakasvibiswa.Kuwedzera, X-ray photoelectron spectroscopy (XPS) yakashandiswa kuona kugadzikana kweoxide film passivation pasi pesimba remhepo yakayerwa yegungwa ine piefinodonas scanning pasi pePseutlomonas laser. maikorosikopu (CLSM).
Tafura 1 inoronga makemikari e2707 HDSS. Tafura 2 inoratidza kuti 2707 HDSS ine yakanakisa mechanical properties ine simba regoho re650 MPa.Mufananidzo 1 unoratidza optical microstructure yemhinduro inopisa inobatwa 2707 HDSS.Elongated bands of austenite uye ferrite phases pasina secondary phases uye 5000% ine austenite % ine 5 microstructure inogona kuonekwa ferrite phases.
Figure 2a inoratidza yakavhurika redunhu zvingangoitika (Eocp) maringe ne exposure nguva data ye2707 HDSS mu abiotic 2216E svikiro uye P. aeruginosa muto kwemazuva 14 pa 37 °C.Inoratidza kuti yakakura uye yakakosha shanduko muEocp inoitika mukati memaawa 24 ekutanga. The Eocp. 16 h ndokuzodonha zvakanyanya, kusvika -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 ma electrochemical corrosion parameter values ​​​​e2707 HDSS samples dzakafumurwa kune abiotic medium uye Pseudomonas aeruginosa inoculated medium kwemazuva 14. Matangenti eanodic uye cathodic curves akaburitswa kuti asvike pamharadzano achiburitsa corrosion current density (corrosion) uye corrosion inogoneka (corrosion) materu (βα uye 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 rekuonesa nguva.A high Rp value inoreva kushomeka kwecorrosion.Mukati memaawa makumi maviri nemana ekutanga, Rp ye2707 HDSS yakasvika pa5 kbiotic 9 cm29 uye 5 kbiotic 9 cm29. kΩ cm2 yePseudomonas 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 cm biological sampuli kΩ.
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 wakaramba wakagadzikana, nepo P. aeruginosa sampuli yakachinja zvikuru mushure memaawa 24 ekutanga. Iko icorr order of samples maeruggino epamusoro maeruggino emhando dzeP. pane zvisiri zvebhayoloji zvinodzora.Maitiro aya anoenderana nemhedzisiro yekupikisa polarization.
EIS ndiyo imwe nzira isingagadzirisike inoshandiswa kuratidza maitiro emagetsi payakaora interfaces.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 kusamira kwemagetsi, Cdl caji yekutamisa magetsi kaviri (Cdl Capatant) Cdl layer Phase Element (CPE) parameters. Aya maparameter akaongororwa zvakare nekukodzera data uchishandisa yakaenzana yedunhu (EEC) modhi.
Mufananidzo 3 unoratidza maNyquist plots (a uye b) 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 3b incubation of the magni. impedance.Ruzivo pamusoro penguva yekuzorora nguva dzose inogona kupiwa nechikamu chechikamu.Mufananidzo 4 unoratidza monolayer (a) uye bilayer (b) zvivako zvemuviri zvakagadzirirwa uye maEEC avo anowirirana.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.Iyo inverse yekudzivirira kutengesa kutengesa (kureva 1 / Rct) inofananidzwa nehuwandu hwekuora.Smaller Rct inoreva kukurumidza kupera kwemazuva 14, Afterbat ye27 mazuva. Pseudomonas aeruginosa samples yakasvika 32 kΩ cm2, idiki kwazvo pane iyo 489 kΩ cm2 yeasiri-biological samples (Table 4).
Mifananidzo yeCLSM nemifananidzo yeSEM ​​muFigure 5 inoratidza zvakajeka kuti kuvharwa kwebiofilm pamusoro pe2707 HDSS muenzaniso mushure memazuva 7 yakaoma.Zvisinei, mushure memazuva gumi nemana, kuvharwa kwebiofilm kwakanga kuri zvishoma uye mamwe masero akafa akaonekwa.Tafura 5 inoratidza huwandu hwebiofilm pa 2707 HDSS specimens mushure memazuva 14. biofilm ukobvu hwakashanduka kubva pa23.4 μm mushure memazuva manomwe kuenda ku18.9 μm mushure memazuva 14. Avhareji yebiofilm ukobvu yakasimbisawo maitiro aya.Yakaderera kubva pa22.2 ± 0.7 μm mushure memazuva manomwe kusvika 17.8 ± 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 akazarurirwa 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 yesimbi uye chiyero cheCromi chepamusoro chinoda chete trace yesimbi uye Feromi. biofilm uye corrosion zvigadzirwa pamusoro pezvienzaniso zvinoratidza kuti simbi matrix yakarasikirwa nezvinhu nekuda kwekuora.
Mushure memazuva gumi nemana, gomba uye pasina P. aeruginosa yakaonekwa mu 2216E yepakati. Pamberi pekunyura, nzvimbo yemuenzaniso yakanga yakatsetseka uye isina kukanganisa (Fig. 7a) .Mushure mekudzivirira uye kubviswa kwezvigadzirwa zvebiofilm uye corrosion, makomba akadzika pamusoro pezvienzaniso zvakaratidzwa pasi pe7 pigure zvakaonekwa pasi pe 7 pigure. pamusoro peasiri-biological control samples (yakanyanya gomba kudzika 0.02 μm) Kudzika kwegomba kwakakonzerwa nePseudomonas aeruginosa kwaive 0.52 μm mushure memazuva manomwe uye 0.69 μm mushure memazuva gumi nemana, zvichibva paavhareji yegomba kudzika kwemasamples matatu (10 yakakura gomba rakasarudzwa 0 ± 2 sampuli dzakasarudzika 0.2) μm uye 0.52 ± 0.15 μm, zvichiteerana (Tafura 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 muzana eFe neCr pamberi peP. aeruginosa (samples A uye B) aive akaderera zvakanyanya pane ayo asiri ebhayoloji control samples (Foreign P, sampuli C uye Druginop sampuli Cr). core-level spectral curve yakaiswa kune ina peak zvikamu zvine simba rinosunga (BE) kukosha kwe574.4, 576.6, 578.3 uye 586.8 eV, iyo inogona kuverengerwa kuCr, Cr2O3, CrO3 uye Cr (OH) 3, zvichiteerana, isiri biological Cr. 2p core-level spectrum ine mapikisi makuru maviri eCr (573.80 eV yeBE) uye Cr2O3 (575.90 eV yeBE) muFig. 9c uye d, zvichienderana.Musiyano unoshamisa pakati peabiotic uye P. aeruginosa samples kwaiva kuvapo kweCr6 + 38 yeC. eV) pasi peiyo biofilm.
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-defect-free chloride. microstructure inobatsira pakugadzikana kwemaitiro uye kusagadzikana kwekuora.Zvisinei, pasinei nekupikisa kwayo 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 broth 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 yekuvhara iyo inovhara biofilm inova nzvimbo yepamusoro yeEocp. yakanyatsogadzikana36.Zvisinei, chiyero cheEocp yehupenyu chaive chakakwirira kudarika cheEocp isiri yehupenyu.Pane chikonzero chekutenda kuti mutsauko uyu unokonzerwa neP. aeruginosa biofilm formation.Mumufananidzo 2d, pamberi peP. aeruginosa, icorr value ye2707 HDSS yakasvika pa μA yakakwira 2707 HDSS yakasvika 0. iyo yeabiotic control (0.063 μA cm-2), iyo yaienderana neRct value yakayerwa neEIS.Pamazuva mashoma ekutanga, impedance values ​​​​muP. aeruginosa broth yakawedzera nekuda kwekubatanidzwa kweP. kuumbwa kwebiofilms uye biofilm metabolites.Naizvozvo, kurwisana kwehutu kwakaderera nekufamba kwenguva, uye kusungirirwa kweP. aeruginosa kwakakonzera kuparara kwenzvimbo.Maitirwo ezvinyorwa zveabiotic akanga akasiyana.Kurwisana kwehutachiona hwehutachiona husina hutano hwakanyanya kudarika kukosha kwakaenzana kwemasampuli akaiswa kuP. 2707 HDSS yakasvika 489 kΩ cm2 pazuva 14, iyo yaiva 15 nguva yeRct value (32 kΩ cm2) pamberi peP. aeruginosa. Naizvozvo, 2707 HDSS ine hukuru hwekudzivisa kuparara munzvimbo isina utachiona, asi haigoni kupikisa MIC kurwisa neP. aeruginosa biomsfilm
Migumisiro iyi inogonawo kuonekwa kubva kune polarization curves muFig. 2b.Anodic branching inonzi inonzi Pseudomonas aeruginosa biofilm formation uye metal oxidation reactions.Panguva imwechete iyo cathodic reaction ndiyo kuderedzwa kweokisijeni.Kuvapo kweP. aeruginosa kwakawedzera zvakanyanya kurora kwepamusoro kurongeka kwepamusoro pehuwandu hwemagnitu. kuti P. aeruginosa biofilm inowedzera kuparara kwenzvimbo ye2707 HDSS.Yuan et al29 vakawana kuti corrosion current density ye 70/30 Cu-Ni alloy yakawedzera pasi pedambudziko reP. 2707 HDSS mubasa iri.Aerobic biofilms inogonawo kuva neokisijeni shoma pasi payo.Saka, kukundikana kudzoreredza pasi pesimbi neokisijeni kunogona 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 eSSsile yakafa, yakawanda ye7 masero e270 HD yakafa pa7 kupera kwechikafu mu2216E svikiro kana kuburitswa kweiyoni yesimbi ine chepfu kubva ku2707 HDSS matrix. Uku ndiko kudzikisira kwebatch experiments.
Mune basa iri, P. aeruginosa biofilm yakakurudzira kuderedzwa kwenzvimbo yeCr uye Fe pasi peiyo biofilm pamusoro pe2707 HDSS pamusoro (Fig. 6) .MuTebhenekeri 6, kuderedzwa kweFe neCr mumuenzaniso D inofananidzwa nemuenzaniso C, zvichiratidza kuti yakanyungudutswa Fe neCr yakakonzerwa neP. simulate nzvimbo dzegungwa.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.Kuenzaniswa neP. kune yakasimba Cl-kupikisa kwe2707 HDSS munzvimbo dzeabiotic.Mufananidzo 9 unoratidza kuvapo kweCr6 + mufirimu yepasisiti.Inogona kunge yakabatanidzwa mukubviswa kweCr kubva panzvimbo dzesimbi neP. aeruginosa biofilms, sezvakakurudzirwa 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 meiyo yakawanda. Iyo pH yeiyo isiri yebhayoloji haina kuchinja zvakanyanya. 7.5) panguva yekuedzwa kwemazuva gumi nemana. Kuwedzera kwepH mumhepo inoculation mushure mekugadzirisa kwakakonzerwa nebasa remagetsi reP.
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 yakataurwa pasi peDSS ye9. data inoratidza kuti 2707 HDSS inoratidzira nani MIC kuramba kana ichienzaniswa ne2205 DSS. Izvi hazvifanirwe kushamisa, sezvo 2707 HDSS ine chromium yakakwira, ichipa passivation inogara kwenguva refu, nekuda kweiyo yakaenzana chikamu chimiro pasina inokuvadza yechipiri precipitates, zvichiita kuti zviomere P. aeruginosa kudzika uye kutanga mapoinzi eclipse.
Mukupedzisa, MIC pitting yakawanikwa pamusoro pe2707 HDSS muP. aeruginosa muto kana ichienzaniswa negomba risingakoshi mu abiotic media.Iri basa rinoratidza kuti 2707 HDSS ine nani MIC inopikisa 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 ye 1-SSor ye 1 corped HDS kana 1 corped ye 1. ine nzvimbo yepamusoro yakashama ye1 cm2 yakakwenenzverwa kusvika 2000 grit nesilicon carbide bepa uye yakawedzera kukwenenzverwa ne 0.05 μm Al2O3 poda suspension.Mativi nepasi zvinodzivirirwa nependi inert.Mushure mekuoma, zvienzaniso zvakasukwa nemvura isina tsvina yakasvibiswa uye yakasvibiswa ne5vl / vl5. ipapo mhepo-yakaomeswa pasi pe ultraviolet (UV) chiedza kwemaawa 0.5 isati yashandiswa.
Marine Pseudomonas aeruginosa MCCC 1A00099 strain yakatengwa kubva ku Xiamen Marine Culture Collection Center (MCCC), China. Qingdao, China).Medium (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 SrCl8 30, 0.2, 0.2 SrCl2, 0.2 0.004 NaSiO3, 0016 NH3, 0016 NH3, 0016 NaH2PO4 , 5.0 peptone, 1.0 yeast extract uye 0.1 ferric citrate.Autoclave pa 121 ° C kwemaminitsi makumi maviri isati yasvika. Verenga sessile pasi uye planktonic masero 4 hemocytomic pa 4 hemocytomic cell magnification.The first cell concentration ye planktonic Pseudomonas aeruginosa pakarepo mushure mekudzivirira yaiva inenge 106 masero / ml.
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, kushanda se-counter uye mareferensi emagetsi, zvichiteerana.Kuita ma electrode anoshanda, rabha-yakavharidzirwa yakavharwa, yakavharwa nerabha yakavharwa nemhangura yakavharwa ne1 copper imwe neimwe. cm2 yenzvimbo yakazaruka ye-single-sided surface ye electrode inoshanda.Pakati pezviyero zve electrochemical, sampuli dzakaiswa mu 2216E svikiro uye dzakachengetwa pamhepo inopisa yekudzivirira (37 ° C) mumvura yekugezera mvura.OCP, LPR, EIS uye data inogona kusimba polarization yakayerwa uchishandisa Autolab potentiostat (Reference 600s Instrumentation, USA, Inc. chiyero che 0.125 mV s-1 pamusoro pe -5 uye 5 mV neEocp uye sampling frequency ye 1 Hz.EIS yakaitwa neine sine wave muhuwandu hwehuwandu hwe0.01 kusvika ku10,000 Hz uchishandisa 5 mV yakashandiswa voltage panzvimbo yakadzikama Eocp. Pamberi pekukwanisa kutsvaira kwe electrodes yakasununguka, iyo electrodes yakasununguka yakatsvaira, iyo inogona kutsvaira yakasununguka. yakasvika.Polarization curves yakabva yamhanya kubva -0.2 kusvika 1.5 V vs. Eocp pa scan rate ye 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 ne 10 wt.% potassium hydroxide solution.
Mushure mekuiswa, samples dzakashambidzwa katatu nephosphate-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%, 8 0, 6% % , 50% 0, 7% , 50%, 8%, 7% . 95% uye 100% 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 zvikuru P. aeruginosa masero pamusoro pemuenzaniso wega wega.Ita EDSAic analysis kuti uwane kemikari yeMCLSM Confoics scanning. (LSM 710, Zeiss, Germany) yakashandiswa kuyera gomba rakadzika.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 chekuedza.
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 5ra resolution. saizi.
Mienzaniso yakavharidzirwa yakabviswa uye yakashambidzwa zvinyoro-nyoro nePBS (pH 7.4 ± 0.2) ye15 s45. Kuti uone kushanda kwebhakitiriya yebiofilms pamienzaniso, iyo biofilms yakasvibiswa uchishandisa LIVE / DEAD BacLight Bacterial Viability Kit (Invitrogen, Eugene, Eugene, Eugene, Eugene, T. Fluorescent SYTO-9 dhayi uye dzvuku fluorescent propidium iodide (PI) dhayi.Pasi peCLSM, madotsi ane fluorescent girini uye tsvuku anomiririra masero mupenyu uye akafa, zvichiteerana.Pakusvibisa, musanganiswa we 1 ml une 3 μl SYTO-9 uye 3 μl PI mhinduro yakavharirwa mukati meiyo 20 maminetsi aC tembiricha mukati me20. masampuli akaonekwa pawavelengths maviri (488 nm yemasero mhenyu uye 559 nm yemasero akafa) uchishandisa Nikon CLSM muchina (C2 Plus, Nikon, Japan) .Biofilm ukobvu hwakayerwa mu3-D scanning mode.
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