Mahalo iā ʻoe no ka kipa ʻana iā Nature.com. ʻO ka polokalamu kele pūnaewele āu e hoʻohana nei he kākoʻo liʻiliʻi no CSS. No ka ʻike maikaʻi loa, paipai mākou e hoʻohana ʻoe i kahi polokalamu kele hou (a i ʻole e hoʻopau i ke ʻano hoʻohālikelike i Internet Explorer).
He pilikia koʻikoʻi ka microbial corrosion (MIC) i nā ʻoihana he nui no ka mea hiki ke hoʻolilo i nā poho waiwai nui. Ua hoʻohana ʻia ka 2707 super duplex stainless steel (2707 HDSS) i nā kaiaola moana ma muli o kona kūʻē ʻana i nā kemika maikaʻi loa. Ua hōʻike ʻia ka nānā ʻana i ka electrochemical ma ke alo o Pseudomonas aeruginosa biofilm ma 2216E medium, aia kahi hoʻololi maikaʻi i ka hiki ke corrosion a me ka piʻi ʻana o ka nui o ka corrosion o kēia manawa. m i nā lā 14 o ka incubation. ʻOiai he liʻiliʻi kēia, e hōʻike ana ʻo 2707 HDSS ʻaʻole paʻa loa i ka MIC o nā biofilms P. aeruginosa.
Hoʻohana nui ʻia nā Duplex stainless steels (DSS) i nā ʻoihana like ʻole no kā lākou hui maikaʻi ʻana o nā waiwai mechanical maikaʻi loa a me ke kūpaʻa corrosion1,2. Akā naʻe, ke kū mau nei ka pitting localized a pili ia i ka pono o kēia steel3,4.DSS ʻaʻole kū i ka microbial corrosion (MIC) 5,6. ʻOi aku ka nui o ka pale ʻana i ka corrosion. ʻIke ʻia ʻo Jeon et al7 ʻoiai ʻo ka super duplex stainless steels (SDSS) kekahi mau palena ma ke ʻano o ka corrosion resistance.
ʻO ka pale ʻana o ka corrosion o DSS e pili ana i ka ratio o ka alpha a me ka gamma phases a me ka Cr, Mo a me W i hoʻopau i nā ʻāpana 8, 9, 10 e pili ana i ka lua o ka māhele.HDSS i loaʻa i nā mea kiʻekiʻe o Cr, Mo a me N11, no laila he kūpaʻa maikaʻi maikaʻi loa a me ka waiwai kiʻekiʻe (45-50) Pitting Resistance Equivalent Number (PREN) ( + wt. wt% W) + 16 wt% N12. ʻO kona kūpaʻa corrosion maikaʻi loa e hilinaʻi ʻia ma kahi ʻano kaulike i loaʻa ma kahi o 50% ferrite (α) a me 50% austenite (γ), ʻoi aku ka maikaʻi o ka HDSS a me ke kūpaʻa kiʻekiʻe ma mua o ka DSS13 maʻamau.ʻO nā waiwai corrosion Chloride. ʻO ka hoʻomaikaʻi ʻana i ka corrosion resistance e hoʻonui i ka hoʻohana ʻana i ka HDSS i nā kaiapuni chloride corrosive, e like me nā kaiapuni moana.
He pilikia nui ka MIC i nā ʻoihana he nui e like me ka aila a me ke kinoea a me nā pono wai14. ʻO MIC ka 20% o nā pōʻino corrosion a pau15. ʻO MIC ka microelectrochemical corrosion hiki ke ʻike ʻia ma nā wahi he nui. hoʻomau i ka ikehu e ola ai 17. Ua hōʻike ʻia nā haʻawina MIC hou i ka EET (extracellular electron transfer) ʻo ia ka helu-limiting factor ma MIC i hoʻokomo ʻia e nā microorganisms electrogenic.Zhang et al.18 hōʻike i ka electron mediators accelerate electron hoʻoili ma waena o Desulfovibrio sessificans cell a me 304 stainless steel, e alakaʻi ana i ka hoʻouka kaua MIC koʻikoʻi. Enning et al.19 a me Venzlaff et al.20 ua hōʻike ʻia e hiki i nā biofilms corrosive sulfate-reducing bacteria (SRB) ke hoʻopaʻa pololei i nā electrons mai nā substrate metala, e hopena i ka ʻinoʻino pitting koʻikoʻi.
Ua ʻike ʻia ʻo DSS hiki ke maʻalahi i ka MIC ma nā wahi i loaʻa iā SRB, iron-reducing bacteria (IRB), etc.
ʻO Pseudomonas aeruginosa kahi huaʻona gram-negative motile rod-shaped bacterium i hoʻolaha nui ʻia ma ke ʻano25. ʻO Pseudomonas aeruginosa kekahi pūʻulu microbial nui i loko o ke kai moana, e hana ana i ka MIC i ke kila. Ua pili pono ʻo Pseudomonas i nā hana corrosion a ua ʻike ʻia ʻo ia he colonizer paionia i ka wā o ka hoʻokumu ʻana o biofilm.28 a ʻo Yuan et al.29 ua hōʻike ʻo Pseudomonas aeruginosa i ka hoʻonui ʻana i ka nui o ka corrosion o ke kila māmā a me nā mea hoʻohui i nā wahi wai.
ʻO ka pahuhopu nui o kēia hana ʻo ia ka noiʻi ʻana i nā waiwai MIC o 2707 HDSS i hoʻokumu ʻia e ka marine aerobic bacterium Pseudomonas aeruginosa me ka hoʻohana ʻana i nā ʻano electrochemical, nā ʻenehana analytical surface a me ka nānā ʻana i nā huahana corrosion. o 2707 HDSS.Energy dispersive spectrometer (EDS) ana i hana 'ia no ka huli 'ana i nā mea kemika ma ka corroded surface. Eia kekahi, ua ho'ohana 'ia ka X-ray photoelectron spectroscopy (XPS) anamana'o no ka ho'oholo 'ana i ka pa'a o ka oxide film passivation ma lalo o ka mana o ka moana e loa'a ana Pseudomonas aeruginosa.The pit scanning CLSM ana i lalo o ka microscope scanning CLSM.
Hōʻike ka papa inoa o ka papaʻaina i ka huiʻana o kaʻenehana 2707 HDSS.TAble 2,07 HDRSS
Kiʻi 2a hōʻike hamama kaapuni hiki (Eocp) versus hōʻike manawa ikepili no 2707 HDSS i abiotic 2216E medium a me P. aeruginosa broth no 14 lā ma 37 ° C. It hoike ana i ka nui loa a me ka nui hoololi i loko o Eocp i loko o ka mua 24 hola. The Eocp waiwai ma na hihia elua peaked ma -145 p. 477 mV (vs. SCE) a me -236 mV (vs. SCE) no ka la'ana abiotic a me P.Pseudomonas aeruginosa coupons. Ma hope o 24 hola, ua paʻa ka waiwai Eocp o 2707 HDSS no P. aeruginosa ma -228 mV (vs. SCE), aʻo ka waiwai e pili ana i nā laʻana non-biological ma kahi o -442 mV (vs. SCE).
ʻO ka hoʻāʻo electrochemical o 2707 HDSS specimens i loko o ke ʻano abiotic a me ka broth Pseudomonas aeruginosa ma 37 °C:
(a) Eocp ma ke ano he hana o ka manawa hoolaha, (b) ka polarization curves i ka la 14, (c) Rp ma ke ano he hana o ka manawa hoike a (d) icorr ma ke ano he hana o ka manawa hoike.
Papa 3 papa inoa i ka electrochemical corrosion parameter waiwai o 2707 HDSS laana i hōʻike ʻia i ka abiotic medium a me Pseudomonas aeruginosa inoculated medium no nā lā 14. Ua extrapolated nā tangents o ka anodic a me ka cathodic curves e hōʻea i nā intersections yield corrosion current density (icorr), corrosion β a me nā ʻano maʻamau (Ecorr β) a me nā ʻano o ka corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano o ka corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β) a me nā ʻano hana corrosion (Ecorr β3) a me nā ala e hiki ai i nā kuʻuna. ,31.
E like me ka mea i hōʻike ʻia ma ka Figure 2b, ʻo ka neʻe ʻana i luna o ka P. aeruginosa curve i hoʻonui ʻia i ka Ecorr i hoʻohālikelike ʻia me ka curve abiotic. ʻO ka waiwai icorr, i kūlike me ka corrosion rate, ua hoʻonui ʻia i ka 0.328 μA cm-2 i ka hāpana Pseudomonas aeruginosa, ʻehā mau manawa o ka hāpana non-biological 7 (0μA8 cm).
LPR mea he maʻamau non-destructive electrochemical hana no ka wikiwiki corrosion kālailai.It ua hoʻohana 'ia e aʻo MIC32.Figure 2c hōʻike i ka polarization kū'ē (Rp) e like me ka hana o ka hoolaha manawa. A kiekie Rp waiwai 'o ia hoʻi emi corrosion.I loko o ka mua 24 hola, i ka Rp o 2707 HDSS i hiki i ka nui o ka waiwai o 1955 kΩ kΩ cm2 abiotics a me Psedoma 2 kΩ 9 kΩ. aeruginosa.
Hoʻohālikelike ka waiwai icorr i ka helu corrosion like ʻole. Hiki ke helu ʻia kona waiwai mai ka hoʻohālikelike Stern-Geary,
Ma hope o Zou et al.33, he typical waiwai o ka Tafel slope B ma keia hana i manaoia he 26 mV/dec. Figure 2d hoike mai i ka icorr o ka non-biological 2707 hāpana i noho 'ano paʻa, oiai ka P. aeruginosa hāpana fluctuated nui ma hope o ka mua 24 hola. The icorr aesrugins ​​o ka mahuahua o ka P. Kūlike kēia ʻano me nā hopena kū'ē polarization.
ʻO EIS kekahi ʻano hana nondestructive i hoʻohana ʻia e hōʻike i nā hopena electrochemical i nā interface corroded. Impedance spectra a me ka helu capacitance waiwai o nā specimens i hōʻike ʻia i ka media abiotic a me ka Pseudomonas aeruginosa solution, Rb kū'ē o ka passive film/biofilm i hoʻokumu ʻia ma ka ʻili o ka specimen, Rct charge transfer resistance, Cdl (Constantant electric capacitance parameter) Ph. s ua kālailai hou ʻia ma ka hoʻokomo ʻana i ka ʻikepili me ka hoʻohana ʻana i ke kumu hoʻohālike like (EEC).
Figure 3 hōʻike typical Nyquist paʻa (a a me ka b) a me ka Bode 'āpana (a 'a me b') o 2707 HDSS laana i loko o abiotic medium a me P. aeruginosa broth no okoa incubation times.The anawaena o ka Nyquist apo emi i ke alo o Pseudomonas aeruginosa.The Bode paʻa hōʻike 'ana i ka hoʻomaha manawa i ka magnitation i ka huina ') hiki ke hāʻawi ʻia e ka pae maxima. Hōʻike ka Figure 4 i ka monolayer (a) a me ka bilayer (b) i hoʻokumu ʻia i ke kino kino a me kā lākou EECs pili.
ʻElua mau hiʻohiʻona kino a me nā kaapuni like like no ka hoʻopili ʻana i ka spectrum impedance o ka specimen 2707 HDSS:
kahi Y0 ka nui o ka CPE, j ka helu noonoo a i ole (-1)1/2, ω ka alapine angular, a o n ka CPE mana kuhikuhi malalo iho o ka unity35. ʻO ka hoʻohuli ʻana o ka hoʻoili hoʻoili kūʻai (ie 1/Rct) pili i ka corrosion rate. Smaller Rct 'o ia hoʻi ka wikiwiki corrosion rate27. Ua hiki aku nā laʻana i ka 32 kΩ cm2, ʻoi aku ka liʻiliʻi ma mua o ka 489 kΩ cm2 o nā laʻana non-biological (Pakaukau 4).
ʻO nā kiʻi CLSM a me nā kiʻi SEM ma ke kiʻi 5 e hōʻike maopopo ana i ka uhi ʻana o ka biofilm ma ka ʻili o ka 2707 HDSS specimen ma hope o nā lā 7 he paʻa. μm ma hope o nā lā 7 i 18.9 μm ma hope o nā lā 14. Ua hōʻoia pū ka mānoanoa biofilm maʻamau i kēia ʻano.
(a) 3-D CLSM kiʻi ma hope o 7 lā, (b) 3-D CLSM kiʻi ma hope o 14 lā, (c) SEM kiʻi ma hope o 7 lā a (d) SEM kiʻi ma hope o 14 lā.
Ua hōʻike ʻo EDS i nā mea kemika i loko o nā biofilms a me nā huahana corrosion ma nā laʻana i hōʻike ʻia i ka P. aeruginosa no nā lā 14. Hōʻike ka Figure 6 i ka ʻike o C, N, O, a me P i loko o nā biofilms a me nā huahana corrosion ʻoi aku ka kiʻekiʻe ma mua o nā metala ʻole, no ka mea pili kēia mau mea me nā biofilms a me kā lākou metabolites. ma ka ʻili o nā mea hoʻohālike e hōʻike ana ua nalowale ka matrix metala ma muli o ka ʻino.
Ma hope o nā lā 14, ua ʻike ʻia ka lua me ka ʻole o P. aeruginosa i ka 2216E medium. Ma mua o ka hoʻoulu ʻana, ua maʻalahi ka ʻili o ka specimen a me ke kīnā ʻole (Fig. 7a). -biological control samples (maximum pit depth 0.02 μm). ʻO ka hohonu o ka lua nui i hana ʻia e Pseudomonas aeruginosa he 0.52 μm ma hope o 7 lā a me 0.69 μm ma hope o 14 mau lā, e pili ana i ka awelika o ka hohonu lua o 3 samples (10 kiʻekiʻe lua μ0 i koho ʻia no kēlā me kēia helu ± 2μm. 0.52 ± 0.15 μm, i kēlā me kēia (Paukū 5).
(a) Ma mua o ka hoʻolaha ʻana, (b) 14 mau lā i loko o ke ʻano abiotic a (c) 14 mau lā i ka broth Pseudomonas aeruginosa.
Hōʻike ka Figure 8 i ka XPS spectra o nā hāpana like ʻole, a ua hōʻuluʻulu ʻia nā haku mele i kālailai ʻia no kēlā me kēia ʻili ma ka Papa 6. Ma ka Papa 6, ʻo nā pākēneka atomika o Fe a me Cr i ke alo o P. aeruginosa (nā laʻana A a me B) ʻoi aku ka haʻahaʻa ma mua o nā mea hoʻokele non-biological control samples (nā laʻana C a me Drugsapp. k mau mea me ka ikehu paʻa (BE) waiwai o 574.4, 576.6, 578.3 a me 586.8 eV, hiki ke pili ia Cr, Cr2O3, CrO3 a me Cr(OH)3, pakahi (Fig. 9a a me b). a me Cr2O3 (575.90 eV no BE) ma ka Fig. 9c a me d. ʻO ka ʻokoʻa ʻoi loa ma waena o nā laʻana abiotic a me P. aeruginosa ʻo ia ka hiki ʻana o Cr6+ a me kahi hakina pili kiʻekiʻe o Cr(OH)3 (BE o 586.8 eV) ma lalo o ka biofilm.
ʻO ka laulā XPS spectra o ka ʻili o ka 2707 HDSS specimen i loko o nā media ʻelua he 7 mau lā a me 14 mau lā.
(a) 7 lā o ka ʻike ʻana i ka P. aeruginosa, (b) 14 mau lā o ka ʻike ʻana iā P. aeruginosa, (c) 7 mau lā ma ke ʻano abiotic a (d) 14 mau lā i ka ʻano abiotic.
Hōʻike ʻo HDSS i nā pae kiʻekiʻe o ka pale ʻana i ka corrosion ma ka hapa nui o nā kaiapuni. Kim et al.Ua hōʻike ʻo 2 ua wehewehe ʻia ʻo UNS S32707 HDSS ma ke ʻano he DSS i hoʻohui nui ʻia me kahi PREN ʻoi aku ka nui ma mua o 45. ʻO ka waiwai PREN o ka 2707 HDSS specimen i kēia hana he 49. ʻO kēia ma muli o kona kiʻekiʻe chromium a me ka molybdenum kiʻekiʻe a me nā pae Ni, he mea pono i ka acidic a me ka kiʻekiʻe chloride ka hoʻohui ʻana a me ka hoʻohui maikaʻi ʻole no ka micro chloride. ka pale ʻana i ka corrosion. Akā naʻe, ʻoiai ke kūpaʻa maikaʻi ʻana o ke kemika, ʻo ka ʻikepili hoʻokolohua ma kēia hana ke hōʻike nei ʻaʻole pale loa ʻo 2707 HDSS i ka MIC o nā biofilm P. aeruginosa.
Ua hōʻike ʻia nā hopena electrochemical i ka nui o ka corrosion o 2707 HDSS i ka broth P. aeruginosa i hoʻonui nui ʻia ma hope o 14 mau lā i hoʻohālikelike ʻia me ka mea ola ʻole. , Ua oi aku ka ki'eki'e o ka Eocp biological ma mua o ka Eocp non-biological. Aia ke kumu e mana'o'i'o ai i keia 'oko'a ma muli o ka P. aeruginosa biofilm ho'okumu 'ana. Ma ka Fig. 2d, ma ke alo o P. aeruginosa, ka waiwai icorr o 2707 HDSS i hiki i ka 0.627 μA cm-2, he mea ia o ka mana o ka magnit-2, ka mea i oi aku ka mana o ka magnit 6 o ka magnitude 6. kūlike me ka Rct waiwai ana e EIS. I loko o nā lā mua, impedance waiwai i loko o P. aeruginosa broth ma muli o ka pili ana o P. aeruginosa pūnaewele a me ka hookumu ana o biofilms. Eia naʻe, i ka biofilm uhi piha i ka ili o ka specimen, i ka impedance emi iho ka impedance. Ua hoouka muaʻia ka pale pale i ka mua ma muli o ke kukulu ana o ka biofilm a me ka biofilm. ʻO ka hoʻopili ʻana o P. aeruginosa i kumu i ka corrosion localized. Ua ʻokoʻa nā ʻano o ka media abiotic. Ua ʻoi aku ka kiʻekiʻe o ka corrosion kū'ē o ka non-biological control ma mua o ka waiwai kūpono o nā laʻana i hōʻike ʻia i ka broth P. aeruginosa. o P. aeruginosa. No laila, he 2707 HDSS ke kū'ē i ka corrosion maikaʻi loa i loko o kahi wahi sterile, akā,ʻaʻole kū'ē i ka MIC hoʻoukaʻia e P. aeruginosa biofilms.
Hiki ke ʻike ʻia kēia mau hopena mai nā ʻōkuhi polarization ma Fig. 2b. Ua pili ka lālā anodic i ka Pseudomonas aeruginosa biofilm hoʻokumu a me nā mea hoʻoheheʻe metala. sion o 2707 HDSS.Yuan et al29 i ike i ka corrosion o keia manawa density o 70/30 Cu-Ni alloy ua mahuahua ma lalo o ka ho'āʻo o P. aeruginosa biofilm.This paha ma muli o ka biocatalysis o oxygen hoemi e Pseudomonas aeruginosa biofilms. This observation may also explain the MIC of 2707 HDSS have also less oxygen work. -passivate i ka ʻili metala e ka oxygen hiki ke lilo i mea kōkua i ka MIC ma kēia hana.
ʻO Dickinson et al.Ua manaʻo ʻo 38 e hiki ke hoʻopili pololei ʻia nā pākēneka o nā kemika a me ka electrochemical e ka metabolic activity o sessile bacteria ma ka ʻili o ka specimen a me ke ʻano o nā huahana corrosion. ka 2216E medium a i ʻole ka hoʻokuʻu ʻana i nā ion metala ʻawaʻawa mai ka matrix 2707 HDSS. He palena kēia o nā hoʻokolohua batch.
Ma keia hana, ka P. aeruginosa biofilm paipai i ka local depletion o Cr a me Fe ma lalo o ka biofilm ma ka 2707 HDSS ili (Fig. 6). Ma ka Papa 6, ka hoemi ana o Fe a me Cr i ka laana D i hoohalikeia me ka laana C, e hoike ana i ka Fe a me Cr i hooheheeia i hanaia e P. aeruginosa biofilm hoomau aku ma waho o ka 227 biofilm. ʻO 7700 ppm Cl-, ka mea i hoʻohālikelike ʻia me ka mea i loaʻa i loko o ka wai kai maoli. ʻO ka hele ʻana o 17700 ppm Cl- ke kumu nui o ka emi ʻana o Cr i nā lā 7- a me 14 mau lā abiotic i kālailai ʻia e XPS. . Hōʻike ka Figure 9 i ka hele ʻana o Cr6 + i ka kiʻiʻoniʻoni passivation. Hiki ke komo i ka wehe ʻana o Cr mai nā mea kila e nā biofilms P. aeruginosa, e like me ka manaʻo o Chen a me Clayton.
Ma muli o ka ulu ʻana o ka bacteria, ʻo 7.4 a me 8.2 ka pH o ka waena ma mua a ma hope o ka mahiʻai ʻana. No laila, ma lalo o ka biofilm P. aeruginosa, ʻaʻole paha e lilo ka corrosion acid i mea kumu i kēia hana ma muli o ke kiʻekiʻe o ka pH i loko o ka nui. .ʻO ka piʻi ʻana o ka pH i loko o ka inoculation medium ma hope o ka incubation ma muli o ka hana metabolic o P. aeruginosa a ua ʻike ʻia he hopena like i ka pH me ka loaʻa ʻole o nā ʻāpana hoʻāʻo.
E like me ka mea i hōʻike ʻia ma ka Figure 7, ʻo ka hohonu hohonu o ka lua i hana ʻia e P. aeruginosa biofilm he 0.69 μm, ʻoi aku ka nui ma mua o ke ʻano o ka medium abiotic (0.02 μm). Ua kūlike kēia me ka ʻikepili electrochemical i hōʻike ʻia ma luna. Hōʻike ʻo 07 HDSS i ka pale MIC maikaʻi aʻe i ka hoʻohālikelike ʻia me 2205 DSS. ʻAʻole kēia he mea kupanaha, no ka mea, ʻoi aku ka nui o ka chromium ma 2707 HDSS, e hāʻawi ana i ka passivation lōʻihi, ma muli o ke ʻano o ka pae kaulike me ka ʻole o nā precipitates lua pōʻino, e ʻoi aku ka paʻakikī o ka P. aeruginosa e depassivate a hoʻomaka i ka eclipse.
I ka hopena, ua loaʻa ka MIC pitting ma ka ʻili o 2707 HDSS i ka P. aeruginosa broth i hoʻohālikelike ʻia me ka negligible pitting i loko o ka media abiotic. Hōʻike kēia hana i ka 2707 HDSS i ʻoi aku ka maikaʻi o ka MIC kūʻē ma mua o 2205 DSS, akā ʻaʻole ia e pale ʻia i ka MIC ma muli o ka biofilm P. aeruginosa. ʻO kēia mau ʻike i koho ʻia i ke ola kino kūpono a me ke koho ʻana i ke ola kino kūpono i ke koho ʻana i ke ola kino ma ke koho.
Hāʻawi ʻia ka coupon no 2707 HDSS e ke Kula ʻo Metallurgy o Northeastern University (NEU) ma Shenyang, Kina. Ua hōʻike ʻia ka ʻāpana elemental o 2707 HDSS ma ka Papa 1, i hoʻopaʻa ʻia e ka NEU Materials Analysis and Testing Department. 1 knm2 i hoʻomaʻamaʻa ʻia i 2000 grit me ka pepa silicon carbide a hoʻomaʻamaʻa hou ʻia me ka 0.05 μm Al2O3 pauka hoʻokuʻu ʻia. Ua pale ʻia nā ʻaoʻao a me lalo e ka pena ʻole. hola ma mua o ka hoʻohana ʻana.
Ua kūʻai ʻia ʻo Marine Pseudomonas aeruginosa MCCC 1A00099 strain mai Xiamen Marine Culture Collection Center (MCCC), Kina. Ua ulu ʻia ʻo Pseudomonas aeruginosa i ka aerobically ma 37 ° C i 250 ml flasks a me 500 ml electrochemical glass cell me ka hoʻohana ʻana i ka Marine 2216E Liquid medium (Qindao. : 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 SrBr2, 0.08 SrBr2, 0.03, Na NH 0016 NH3, 0016 NaH2PO4 , 5.0 peptone, 1.0 hua hū a me 0.1 ferric citrate.Autoclave ma 121 ° C no 20 mau minuke ma mua o ka inoculation. E helu i nā sessile a me nā pūnaewele planktonic me ka hoʻohanaʻana i ka hemocytometer ma lalo o ka microscope māmā ma 4000nicX ka hoʻolālā pūnaewele mua ma hope koke o ka P. aia ma kahi o 106 mau keneta/ml.
Ua ho'āʻo Electrochemical i loko o ka Classic ekolu-electrode aniani keena me ka medium volume o 500 ml.A platinum pepa a me ka saturated calomel electrode (SCE) ua pili i ka reactor ma Luggin capillaries piha me ka paakai alahaka, lawelawe e like me ka counter a me ka kuhikuhi electrodes, pakahi. -ʻaoʻao ili ili no ka hana electrode. I ka wā electrochemical ana, ua hoʻokomo 'ia nā laʻana ma 2216E medium a mālama 'ia ma ka incubation wela mau (37 °C) i loko o ka wai auau.OCP, LPR, EIS a me ka hiki dynamic polarization ikepili ua ana ia me ka Autolab potentiostat (Reference 600TM, Gamry Instruments ma VPR ho'āʻo 2 helu o ka helu o ka 5VPR scans o USA). ma luna o ka laula o -5 a me 5 mV me Eocp a me ka la'ana la'ana o 1 Hz.EIS ua hana 'ia me ka hawewe sine ma ke alapine o ka 0.01 a hiki i 10,000 Hz me ka 5 mV i hoohana ia ka uila ma steady state Eocp. Ma mua o ka hiki ke kahili, na electrodes i ka hamama-kaapuni mode a hiki i ka corrosion hiki i ka stable. 5 V vs. Eocp ma ka helu scan o 0.166 mV / s. Ua hana hou kēlā me kēia ho'āʻo 3 manawa me ka P. aeruginosa a me ka ʻole.
ʻO nā hiʻohiʻona no ka nānā ʻana i ka metallographic i kālai ʻia me ka 2000 grit wet SiC pepa a laila hoʻomaʻamaʻa hou ʻia me ka 0.05 μm Al2O3 pauka hoʻokuʻu no ka nānā ʻana. Ua hana ʻia ka loiloi metallographic me ka microscope optical.
Ma hope o ka incubation, holoi ʻia nā laʻana i 3 mau manawa me ka phosphate-buffered saline (PBS) solution (pH 7.4 ± 0.2) a laila hoʻopaʻa ʻia me 2.5% (v/v) glutaraldehyde no 10 mau hola e hoʻoponopono ai i nā biofilms. 0% v/v) o ka ethanol ma mua o ka maloʻo ʻana o ka ea. ʻO ka hope, ua sputtered ka ʻili o ka hāpana me kahi kiʻi gula no ka hāʻawi ʻana i ka conductivity no ka nānā ʻana SEM. Ua kālele ʻia nā kiʻi SEM i nā kiko me nā puʻupuʻu P. aeruginosa sessile loa ma ka ʻili o kēlā me kēia specimen. hohonu. No ka nānā ʻana i nā lua ʻino ma lalo o ka biofilm, ua hoʻomaʻemaʻe mua ʻia ka ʻāpana hoʻāʻo e like me ka Chinese National Standard (CNS) GB / T4334.4-2000 e wehe i nā huahana corrosion a me biofilm ma ka ʻili o ka ʻāpana hoʻāʻo.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 surface analysis system, Thermo VG, USA) ua hana 'ia me ka monochromatic X-ray source (aluminium Kα laina ma 1500 eV ikehu a me 150 W mana) ma luna o ka laulā ikehu 0 ma lalo o nā kūlana ma'amau -1350 eV.
Ua wehe ʻia nā mea hoʻoheheʻe incubated a holoi ʻia me ka PBS (pH 7.4 ± 0.2) no 15 s45. No ka nānā ʻana i ka hiki ʻana o ka maʻi bacteria o nā biofilms ma nā mea hoʻohālike, ua hoʻopaʻa ʻia nā biofilms me ka hoʻohana ʻana i ka LIVE / DEAD BacLight Bacterial Viability Kit (Invitrogen, Eugene, OR, ʻO ka ʻōmaʻomaʻo kitordy SY, ʻelua flue, USA). a me ka ʻulaʻula fluorescent propidium iodide (PI) dye.Ma lalo o CLSM, nā kiko me ka fluorescent omaomao a me ka ulaula e hoike mai ana i ke ola a me ka make cell, pakahi. nā pūnaewele a me 559 nm no nā pūnaewele make) me ka mīkini Nikon CLSM (C2 Plus, Nikon, Iapana).
Pehea e helu ai i kēia ʻatikala: Li, H. et al.Microbial corrosion of 2707 super duplex stainless steel by marine Pseudomonas aeruginosa biofilm.science.Rep.6, 20190;doi: 10.1038/srep20190 (2016).
Zanotto, F., Grassi, V., Balbo, A., Monticeli, C. & Zucchi, F. Stress corrosion māwae o LDX 2101 duplex kuhiliʻole kila i loko o chloride solution ma ke alo o thiosulfate.coros.science.80, 205–212 (2014).
Kim, ST, Jang, SH, Lee, IS & Park, YS Ka hopena o ka hoʻoponopono wela a me ka naikokene i loko o ka pale kinoea ma ka pitting corrosion kū'ē o super duplex stainless steel welds.coros.science.53, 1939–1947 (2011).
Shi, X., Avci, R., Geiser, M. & Lewandowski, Z. He Haʻawina Kemimi Hoʻohālikelike o Microbial a me Electrochemically Induced Pitting Corrosion ma 316L Stainless Steel.coros.science.45, 2577–2595 (2003).
Luo, H., Dong, CF, Li, XG & Xiao, K. Electrochemical hana o 2205 duplex kuhiliʻole kila i loko o ka alkaline solutions o ka pH likeʻole i ke alo o chloride.Electrochim.Journal.64, 211-220 (2012).
Little, BJ, Lee, JS & Ray, RI ʻO ka hopena o nā biofilms moana ma ka corrosion: kahi loiloi pōkole.Electrochim.Journal.54, 2-7 (2008).