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Microbial corrosion (MIC) matsala ce mai tsanani a masana'antu da yawa saboda yana iya haifar da asarar tattalin arziki mai yawa.2707 super duplex bakin karfe (2707 HDSS) an yi amfani dashi a cikin yanayin ruwa saboda kyakkyawan juriya na sinadarai. Duk da haka, juriya ga MIC ba a gwada shi ba. Binciken rochemical ya nuna cewa a gaban Pseudomonas aeruginosa biofilm a cikin matsakaici na 2216E, akwai canji mai kyau a cikin yiwuwar lalata da kuma karuwa a cikin lalata halin yanzu. .69 μm a cikin kwanaki 14 na incubation. Ko da yake wannan karami ne, yana nuna cewa 2707 HDSS ba ta da cikakkiyar kariya ga MIC na P. aeruginosa biofilms.
Duplex bakin karfe (DSS) ana amfani da ko'ina a cikin daban-daban masana'antu domin su manufa hade da kyau kwarai inji Properties da lalata resistance1,2.Amma, gida pitting har yanzu faruwa da kuma rinjayar da mutuncin wannan steel3,4.DSS ba resistant zuwa microbial lalata (MIC) 5,6.Duk da fadi da kewayon aikace-aikace na DSS, akwai har yanzu da tsada juriya na DSS. Ana buƙatar kayan da ke da juriya mafi girma.Jeon et al7 gano cewa ko da super duplex bakin karfe (SDSS) suna da wasu gazawa cikin sharuddan lalata juriya.Saboda haka, super duplex bakin karfe (HDSS) tare da mafi girma lalata juriya ake bukata a wasu aikace-aikace.Wannan ya haifar da ci gaban HDSS sosai alloyed.
Rashin juriya na DSS ya dogara ne akan rabo na alpha da gamma da kuma Cr, Mo da W yankunan da suka lalace 8, 9, 10 kusa da kashi na biyu.HDSS ya ƙunshi babban abun ciki na Cr, Mo da N11, don haka yana da kyakkyawan juriya na lalata da kuma babban darajar (45-50) Pitting Resistance Equivalent Number (PREN + 3%) .wt. % W) + 16 wt% N12. Kyakkyawan juriya na lalata yana dogara ne akan daidaitaccen abun da ke dauke da kusan 50% ferrite (α) da 50% austenite (γ), HDSS yana da mafi kyawun kayan aikin injiniya da juriya mafi girma fiye da na al'ada DSS13.Abubuwan lalata chloride.Ingantaccen juriya na lalata yana faɗaɗa amfani da HDSS a cikin ƙarin yanayin lalata chloride, kamar yanayin ruwa.
MICs babbar matsala ce a masana'antu da yawa kamar man fetur da gas da kayan aikin ruwa14.MIC yana da kashi 20% na duk lalacewar lalacewa15.MIC shine lalatawar bioelectrochemical wanda za'a iya lura da shi a yawancin yanayi.Biofilms wanda ke samuwa a kan sassan karfe yana canza yanayin yanayin electrochemical, ta haka yana rinjayar tsarin lalata. samun kuzari mai dorewa don tsira17. Binciken MIC na baya-bayan nan ya nuna cewa EET (canja wurin wutar lantarki na waje) shine ƙayyadaddun ƙayyadaddun ƙima a cikin MIC da ƙwayoyin cuta na lantarki ke haifar da su.Zhang et al.18 ya nuna cewa masu shiga tsakani na lantarki suna hanzarta canja wurin lantarki tsakanin sel Desulfovibrio sessificans da 304 bakin karfe, wanda ke haifar da mummunan harin MIC.Enning et al.19 da Venzlaff et al.20 ya nuna cewa ƙwayoyin cuta masu rage sulfate (SRB) biofilms na iya ɗaukar electrons kai tsaye daga abubuwan ƙarfe na ƙarfe, yana haifar da lalatawar rami mai tsanani.
DSS an san yana da saurin kamuwa da MIC a cikin mahallin da ke ɗauke da SRB, ƙwayoyin cuta masu rage baƙin ƙarfe (IRB), da sauransu.
Pseudomonas aeruginosa ne mai gram-korau motile sanda-dimbin kwayoyin cuta da aka rarraba a cikin yanayi25.28 da Yuan et al.29 ya nuna cewa Pseudomonas aeruginosa yana da hali don ƙara yawan lalata na ƙarfe mai laushi da gami a cikin mahalli mai ruwa.
Babban makasudin wannan aikin shine don bincika abubuwan MIC na 2707 HDSS da ke haifar da kwayar cutar aerobic na ruwa ta Pseudomonas aeruginosa ta amfani da hanyoyin electrochemical, fasahar nazarin sararin samaniya da kuma nazarin samfuran lalata. Nazarin ilimin kimiyyar da suka haɗa da Buɗe Mai yiwuwa (OCP), Resistance Linear Polarization Resistance (LPR), Electroscopy Impedance, Pseudomonas aeruginosa, Pseudomonas aeruginosa, da Pseudomonas aeruginosa, an yi nazari akan halayen haɓakawa. na 2707 HDSS.Energy dispersive spectrometer (EDS) bincike da aka yi don gano sinadaran abubuwa a kan lalata surface. Bugu da kari, X-ray photoelectron spectroscopy (XPS) bincike da aka yi amfani da domin sanin da kwanciyar hankali na oxide film passivation a karkashin rinjayar wani marine yanayi dauke da Pseudomonas aeruginosa.The rami confocus laser auna a karkashin microscope.
Table 1 ya bada jerin sunayen sinadaran sinadaran 2707 HDSS.Table 2 ya nuna cewa 2707 HDSS yana da kyau kwarai inji Properties tare da yawan amfanin ƙasa ƙarfi na 650 MPa.Hoto 1 ya nuna Tantancewar microstructure na bayani zafi bi 2707 HDSS.Elongated makada na austenite da ferrite bulan ba tare da sakandare bulan za a iya gani a cikin wani kashi% 5 microstrurite.
Hoto 2a yana nuna yiwuwar yiwuwar budewa (Eocp) tare da bayanan lokaci na bayanai don 2707 HDSS a cikin abiotic 2216E matsakaici da P. aeruginosa broth na 14 kwanaki a 37 ° C. Yana nuna cewa mafi girma da gagarumin canji a cikin Eocp yana faruwa a cikin sa'o'i 24 na farko. Ƙimar Eocp a cikin duka lokuta biyu ya kai a -145.6 m a kusa da -145.6. 77 mV (vs. SCE) da -236 mV (vs. SCE) don samfurin abiotic da P, bi da bi).Pseudomonas aeruginosa takardun shaida, bi da bi.Bayan 24 hours, da Eocp darajar 2707 HDSS ga P. aeruginosa ya kasance ingantacciyar barga a -228 mV (vs. SCE), yayin da daidai darajar ga wadanda ba nazarin halittu samfurori ya kasance kamar -442 mV (vs. SCE) .Eocp a wajen wani low gaban Posagino.
Gwajin Electrochemical na samfuran 2707 HDSS a cikin matsakaicin abiotic da Pseudomonas aeruginosa broth a 37 ° C:
(a) Eocp a matsayin aikin lokacin fallasa, (b) magudanar polarization a rana ta 14, (c) Rp a matsayin aikin lokacin fallasa da (d) icorr a matsayin aikin lokacin fallasa.
Table 3 ya bada jerin sunayen ma'auni na ma'auni na electrochemical na samfurori na 2707 HDSS da aka fallasa zuwa matsakaicin abiotic da Pseudomonas aeruginosa inoculated matsakaici don kwanaki 14. The tangents na anodic da cathodic masu lankwasa da aka extrapolated su isa a intersections samar da lalata halin yanzu yawa (icorr), lalata β3 hanyoyin da za a lalata (lalata) da kuma lalata hanyoyin (icorr). 0,31.
Kamar yadda aka nuna a cikin Hoto 2b, hawan hawan P. aeruginosa zuwa sama ya haifar da karuwa a cikin Ecorr idan aka kwatanta da nau'in abiotic. Ƙimar icorr, wanda ya dace da ƙimar lalata, ya karu zuwa 0.328 μA cm-2 a cikin samfurin Pseudomonas aeruginosa, sau hudu na samfurin da ba na halitta ba (μ 082) .
LPR ne a classic non-destructive electrochemical Hanyar domin m lalata analysis.It kuma an yi amfani da su yi nazarin MIC32.Hoto 2c nuna polarization juriya (Rp) a matsayin aiki na daukan hotuna lokaci.A mafi girma Rp darajar yana nufin kasa lalata. A cikin na farko 24 hours, da Rp na 2707 HDSS ya kai wani matsakaicin darajar 1925 cm Ω Ω Ω2 cm pΩ2 kΩ2 cm pΩ2 kΩ2 p. samfurori na aeruginosa. Hoto 2c kuma ya nuna cewa ƙimar Rp ta ragu da sauri bayan kwana ɗaya sannan kuma ya kasance ba tare da canzawa ba don kwanaki 13 masu zuwa. Ƙimar Rp na samfurin Pseudomonas aeruginosa yana da kusan 40 kΩ cm2, wanda ya fi ƙasa da 450 kΩ cm2 darajar samfurin da ba na halitta ba.
Ƙimar icorr ta yi daidai da daidaitaccen adadin lalata. Ana iya ƙididdige ƙimarsa daga ma'aunin Stern-Geary mai zuwa,
Bayan Zou et al.33, a hankula darajar Tafel gangara B a cikin wannan aikin da aka zaci ya zama 26 mV / Dec. Hoto 2d ya nuna cewa icorr na wadanda ba nazarin halittu samfurin 2707 zauna in mun gwada da barga, yayin da P. aeruginosa samfurin fluctuated ƙwarai bayan na farko 24 hours. The icorr dabi'u na oda na oda magnsa samples anerude mafi girma daga cikin P. yayi daidai da sakamakon juriya na polarization.
EIS wata fasaha ce da ba ta lalacewa da ake amfani da ita don nuna halayen halayen electrochemical a cikin ɓarnawar ɓarna. Impedance spectra da ƙididdige ƙimar ƙima na samfuran da aka fallasa su zuwa kafofin watsa labarai na abiotic da Pseudomonas aeruginosa bayani, Rb juriya na fim / biofilm da aka kafa akan farfajiyar samfurin, Rct cajin wutar lantarki sau biyu, CdC Canja wurin wutar lantarki, CdC Canja wurin wutar lantarki, CdC Canja wutar lantarki, Cd Cd da Canja wurin wutar lantarki. CPE) sigogi. An kara nazarin waɗannan sigogi ta hanyar dacewa da bayanai ta hanyar amfani da samfurin daidai (EEC).
Hoto na 3 yana nuna makircin Nyquist na al'ada (a da b) da Bode makirci (a' da b') na samfuran HDSS 2707 a cikin matsakaici na abiotic da P. aeruginosa broth don lokutan shiryawa daban-daban. Diamita na zobe na Nyquist yana raguwa a gaban Pseudomonas aeruginosa. The Bode mãkirci (Fig. 3. Yana nuna karuwa a cikin jimlar lokaci). Za a iya ba da shi ta hanyar maxima. Hoto na 4 yana nuna tsarin tsarin jiki na monolayer (a) da bilayer (b) da kuma daidaitattun EECs.CPE an gabatar da su a cikin tsarin EEC. An bayyana shigar da shi da kuma impedance kamar haka:
Samfuran jiki guda biyu da madaidaitan da'irori masu dacewa don dacewa da bakan impedance na samfurin 2707 HDSS:
inda Y0 shine girman CPE, j shine lambar hasashe ko (-1) 1/2, ω shine mitar angular, kuma n shine ma'aunin wutar lantarki na CPE kasa da haɗin kai35. The inverse na cajin canja wurin juriya (watau 1 / Rct) yayi daidai da ƙimar lalata. Ƙananan Rct yana nufin sauri lalata rate27. s ya kai 32 kΩ cm2, ya fi ƙanƙanta da 489 kΩ cm2 na samfuran da ba na halitta ba (Table 4).
Hotunan CLSM da hotuna na SEM a cikin Hoto 5 sun nuna a fili cewa ɗaukar hoto na biofilm a saman samfurin 2707 HDSS bayan kwanakin 7 yana da yawa. Duk da haka, bayan kwanaki 14, ɗaukar hoto na biofilm ya kasance mai banƙyama kuma wasu matattun kwayoyin halitta sun bayyana.Table 5 yana nuna kauri na biofilm a kan 2707 HDSS samfurori a kan 2707 HDSS samfurori a kan 7. Canje-canje zuwa girman girman P7. 23.4 μm bayan kwanaki 7 zuwa 18.9 μm bayan kwanaki 14. Matsakaicin kauri na biofilm kuma ya tabbatar da wannan yanayin. Ya rage daga 22.2 ± 0.7 μm bayan kwanaki 7 zuwa 17.8 ± 1.0 μm bayan kwanaki 14.
(a) Hoton 3-D CLSM bayan kwanaki 7, (b) Hoton 3-D CLSM bayan kwanaki 14, (c) Hoton SEM bayan kwanaki 7 da (d) Hoton SEM bayan kwanaki 14.
EDS ya bayyana abubuwan sinadarai a cikin biofilms da samfuran lalata akan samfuran da aka fallasa zuwa P. aeruginosa na kwanaki 14. Hoto na 6 ya nuna cewa abun ciki na C, N, O, da P a cikin biofilms da samfuran lalata sun fi girma fiye da abin da ke cikin ƙananan ƙarfe, saboda waɗannan abubuwan suna hade da biofilms da metabolites. daga cikin samfuran suna nuna cewa matrix ɗin ƙarfe ya rasa abubuwa saboda lalata.
Bayan kwanaki 14, an lura da pitting tare da ba tare da P. aeruginosa a cikin matsakaici na 2216E. Kafin ƙaddamarwa, samfurin samfurin ya kasance mai santsi kuma ba tare da lahani ba (Fig. 7a) . samfurori masu sarrafa halittu (matsakaicin zurfin rami 0.02 μm) .Matsakaicin zurfin rami da Pseudomonas aeruginosa ya haifar shine 0.52 μm bayan kwanaki 7 da 0.69 μm bayan kwanaki 14, dangane da matsakaicin matsakaicin zurfin rami na samfuran 3 (10 matsakaicin zurfin zurfin rami na 10.0.0 ± 2 μm don kowane samfurin). 15 μm, bi da bi (Table 5) .Waɗannan ƙimar zurfin rami ƙananan ƙananan ne amma mahimmanci.
(a) Kafin bayyanar, (b) kwanaki 14 a cikin matsakaici na abiotic da (c) kwanaki 14 a cikin Pseudomonas aeruginosa broth.
Hoto 8 yana nuna nau'in XPS na nau'i daban-daban na samfurori daban-daban, kuma abubuwan sinadaran da aka bincikar su ga kowane farfajiya an taƙaita su a cikin Table 6. A cikin Table 6, adadin atomic na Fe da Cr a gaban P. aeruginosa (samfurori A da B) sun kasance da yawa fiye da waɗanda ba na nazarin halittu ba (samfurori C da D) . tted zuwa hudu ganiya aka gyara tare da dauri makamashi (BE) dabi'u na 574.4, 576.6, 578.3 da kuma 586.8 eV, wanda za a iya dangana ga Cr, Cr2O3, CrO3 da Cr (OH) 3, bi da bi (Fig. 9a da b) .Ga wadanda ba na nazarin halittu sperum perum spectr Cr. (573.80 eV don BE) da Cr2O3 (575.90 eV don BE) a cikin siffa 9c da d, bi da bi.Bambanci mafi ban sha'awa tsakanin samfurin abiotic da P. aeruginosa shine kasancewar Cr6 + da ƙananan dangi na Cr (OH) 3 (BE na 586.8 a kusa da biofil).
Faɗin XPS na saman samfurin 2707 HDSS a cikin kafofin watsa labarai guda biyu sune kwanaki 7 da kwanaki 14, bi da bi.
(a) Kwanaki 7 na fallasa zuwa P. aeruginosa, (b) kwanaki 14 na fallasa zuwa P. aeruginosa, (c) kwanaki 7 a matsakaicin abiotic da (d) kwanaki 14 a matsakaicin abiotic.
HDSS yana nuna babban matakan juriya na lalata a yawancin mahalli.Kim et al.2 ya ruwaito cewa an bayyana UNS S32707 HDSS a matsayin DSS mai alloed sosai tare da PREN fiye da 45. Ƙimar PREN na samfurin 2707 HDSS a cikin wannan aikin shine 49. Wannan shi ne saboda babban abun ciki na chromium da high molybdenum da Ni, wanda ke da amfani a cikin acidic da high chloride mahadi, da kuma microcomponent acidic da kuma high chloride yanayi. kwanciyar hankali na ural da juriya na lalata.Duk da haka, duk da kyakkyawan juriya na sinadarai, bayanan gwaji a cikin wannan aikin sun nuna cewa 2707 HDSS ba ta da cikakkiyar kariya ga MIC na P. aeruginosa biofilms.
Sakamakon Electrochemical ya nuna cewa yawan lalata na 2707 HDSS a cikin P. aeruginosa broth ya karu sosai bayan kwanaki 14 idan aka kwatanta da matsakaicin da ba na halitta ba. ological Eocp ya kasance mafi girma fiye da na Eocp ba na halitta ba. Akwai dalilin da za a yi imani da cewa wannan bambancin shine saboda P. aeruginosa biofilm samuwar. A cikin Fig. 2d, a gaban P. aeruginosa, icorr darajar 2707 HDSS ya kai 0.627 μA cm-2, wanda shine tsari mafi girma fiye da girman girman girman girman girman girman girman girman girman girman girman 2707 μA cm-2, wanda shine tsari mafi girma fiye da 3 μC. Tare da ƙimar Rct da aka auna ta hanyar EIS. A cikin 'yan kwanakin farko, ƙimar impedance a cikin P. aeruginosa broth ya karu saboda haɗuwa da kwayoyin halitta na P. aeruginosa da kuma samar da biofilms. Duk da haka, lokacin da biofilm gaba daya ya rufe saman samfurin, impedance yana ragewa.An kai hari na farko na kariya daga biofils a kan ƙananan ƙwayoyin cuta da kuma samar da kwayoyin halitta. , da kuma abin da aka makala na P. aeruginosa ya haifar da lalata a cikin gida. Hanyoyin da ke cikin kafofin watsa labaru na abiotic sun bambanta. Ƙwararrun juriya na tsarin kula da kwayoyin halitta ya kasance mafi girma fiye da daidaitattun samfurori da aka fallasa zuwa P. aeruginosa broth. Bugu da ƙari, don samfurori na abiotic, ƙimar Rct na 2707 HDSS ya kai 429 Rct Rct na 2707 HDSS a ranar 489 kΩ 1 cm Ω Ω 1 cm. ) a gaban P. aeruginosa.Saboda haka, 2707 HDSS yana da kyakkyawan juriya na lalata a cikin yanayi maras kyau, amma ba shi da tsayayya ga harin MIC ta hanyar P. aeruginosa biofilms.
Hakanan ana iya lura da waɗannan sakamakon daga maƙallan polarization a cikin siffa 2b. An danganta rassan anodic zuwa haɓakar biofilm na Pseudomonas aeruginosa da halayen oxidation na ƙarfe. A lokaci guda halayen cathodic shine raguwar oxygen. Kasancewar P. aeruginosa yana ƙaruwa da haɓakar lalata halin yanzu, kusan tsari na Pseudomonas. Lalacewar gida na 2707 HDSS.Yuan et al29 sun gano cewa lalata halin yanzu density na 70/30 Cu-Ni alloy ya karu a ƙarƙashin ƙalubalen P. aeruginosa biofilm. Wannan na iya zama saboda biocatalysis na rage oxygen ta hanyar Pseudomonas aeruginosa biofilms. Wannan kallo na iya zama ƙasa da aikin MIC na HDA. .Saboda haka, rashin nasarar sake yin amfani da karfe ta hanyar iskar oxygen na iya zama abin taimakawa ga MIC a cikin wannan aikin.
Dickinson et al.38 ya ba da shawarar cewa ƙimar sinadarai da halayen electrochemical za a iya shafa su kai tsaye ta hanyar aiki na rayuwa na ƙwayoyin cuta na sessile a saman samfurin da kuma yanayin samfuran lalata. Kamar yadda aka nuna a cikin Hoto 5 da Table 5, duka lambar tantanin halitta da kauri na biofilm sun ragu bayan kwanaki 14. Wannan za a iya bayyana a hankali cewa bayan kwanaki 14, yawancin 7 na sel na HDSS2 sun mutu a cikin sel na HDSS 2 a cikin sel na 7. 16E matsakaici ko sakin ions karfe masu guba daga matrix HDSS 2707. Wannan iyakance ne na gwaje-gwajen batch.
A cikin wannan aikin, P. aeruginosa biofilm ya inganta ƙaddamarwar gida na Cr da Fe a ƙarƙashin biofilm a kan 2707 HDSS surface (Fig. 6) .A cikin Table 6, ragewar Fe da Cr a cikin samfurin D idan aka kwatanta da samfurin C, yana nuna cewa narkar da Fe da Cr da P. aeruginosa biofilm ya haifar ta hanyar P. aeruginosa biofilm 2 ya ci gaba da ci gaba da yin amfani da shi a cikin kwanaki 6. ya ƙunshi 17700 ppm Cl-, wanda yake daidai da wanda aka samo a cikin ruwa na halitta. Kasancewar 17700 ppm Cl- shine babban dalilin da ya rage a cikin Cr a cikin 7- da 14-day abiotic samfurori da aka bincika ta XPS. Idan aka kwatanta da P. aeruginosa samfurori, rushewar Cr a cikin ƙananan ƙwayoyin cuta na Cr a cikin ƙananan ƙwayoyin cuta na 7. Hoto 9 yana nuna kasancewar Cr6 + a cikin fim ɗin wucewa. Yana iya kasancewa cikin cirewar Cr daga saman karfe ta hanyar P. aeruginosa biofilms, kamar yadda Chen da Clayton suka nuna.
Saboda girma na kwayan cuta, da pH dabi'u na matsakaici kafin da kuma bayan namo sun kasance 7.4 da kuma 8.2, bi da bi.Saboda haka, a kasa da P. aeruginosa biofilm, Organic acid lalata ba shi yiwuwa ya zama wani taimako factor ga wannan aiki saboda da in mun gwada da high pH a cikin girma matsakaici.The pH na wadanda ba na nazarin halittu canji a lokacin da 7.4. Lokacin gwaji na kwanaki 14. Ƙarar da pH a cikin matsakaici na inoculation bayan ƙaddamarwa ya kasance saboda aikin motsa jiki na P. aeruginosa kuma an gano cewa yana da tasiri iri ɗaya akan pH idan babu gwajin gwaji.
Kamar yadda aka nuna a cikin Hoto 7, matsakaicin zurfin rami wanda P. aeruginosa biofilm ya haifar shine 0.69 μm, wanda ya fi girma fiye da na matsakaicin abiotic (0.02 μm) .Wannan ya dace da bayanan electrochemical da aka kwatanta a sama. 0.69 μm zurfin rami ya fi sau goma karami fiye da 9.5 μm20 mafi girma fiye da yanayin 9.5 μm20 da aka ruwaito a karkashin yanayin DSS20 da aka ruwaito don SS20 da aka ruwaito don SS20. yana hana mafi kyawun juriya na MIC idan aka kwatanta da 2205 DSS. Wannan bai kamata ya zama abin mamaki ba, kamar yadda 2707 HDSS yana da abun ciki na chromium mafi girma, yana samar da dogon lokaci mai tsawo, saboda tsarin ma'auni na ma'auni ba tare da haɗari na sakandare ba, yana sa ya fi wuya ga P. aeruginosa don ragewa kuma ya fara maki husufi.
A ƙarshe, an samo MIC pitting a saman 2707 HDSS a cikin P. aeruginosa broth idan aka kwatanta da rashin kuskure a cikin kafofin watsa labaru na abiotic.Wannan aikin ya nuna cewa 2707 HDSS yana da mafi kyawun juriya na MIC fiye da 2205 DSS, amma ba shi da cikakken kariya ga MIC saboda P. aeruginosa biofilm. Wadannan binciken da aka kiyasta na ma'auni na ma'auni na ma'auni na ma'auni na ma'auni na ma'auni.
The coupon for 2707 HDSS aka bayar da School of Metallurgy na Northeast University (NEU) a Shenyang, China.The elemental abun da ke ciki na 2707 HDSS da aka nuna a cikin Table 1, wanda aka bincikar da NEU Materials Analysis da Testing Department.All samfurori da aka warware bi da a 1180 °C for 1 hour.Prior zuwa wani yanki na 1180 ° C da aka fallasa da SSPrior zuwa wani yanki na 1. cm2 an goge shi zuwa 2000 grit tare da takarda na silicon carbide kuma ya kara gogewa tare da dakatarwar foda na 0.05 μm Al2O3. An kiyaye bangarorin da kasa ta hanyar inert Paint. Bayan bushewa, an wanke samfurori tare da ruwa mai tsabta da bakararre tare da 75% (v / v0) . haske don 0.5 hours kafin amfani.
Marine Pseudomonas aeruginosa MCCC 1A00099 iri da aka saya daga Xiamen Marine Culture Collection Center (MCCC), China. /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 SrBr2, 0.08 SrBr2, 0.06 N, 0.0H, 0.0HBr2, H0.0. 3, 0016 NH3, 0016 NaH2PO4 , 5.0 pepton, 1.0 yeast tsantsa da 0.1 ferric citrate.Autoclave a 121 ° C na 20 minutes kafin inoculation.Count sessile da planktonic Kwayoyin ta amfani da hemocytometer a karkashin wani haske microscope na farko microscope a 4.0. inoculation ya kasance kusan 106 sel / ml.
Electrochemical gwaje-gwaje da aka yi a cikin wani classic uku-electrode gilashin cell tare da matsakaici girma na 500 ml. A platinum takardar da cikakken calomel electrode (SCE) da aka haɗa zuwa reactor via Luggin capillaries cika da gishiri gadoji, bauta a matsayin counter da kuma tunani electrodes, bi da bi.To sa da aiki electrodes, wani roba-rufi da aka rufe da jan karfe 1 cm da aka haɗe da epacide da wayoyi da aka haɗe da kowane nau'i na igiya da aka haɗe tare da igiya 1. d surface area for the work electrode.A lokacin electrochemical ma'auni, samfurori da aka sanya a cikin 2216E matsakaici da kuma kiyaye a akai shiryawa zafin jiki (37 ° C) a cikin wani ruwa wanka.OCP, LPR, EIS da m tsauri polarization data aka auna ta amfani da wani Autolab potentiostat (Reference 600TM, Gamry Instruments, Gamry Instruments, Inc. 1 da aka rubuta a Amurka). da kewayon -5 da 5 mV tare da Eocp da mitar samfurin na 1 Hz.EIS an yi tare da sine wave a cikin mita mita 0.01 zuwa 10,000 Hz ta amfani da 5 mV amfani da ƙarfin lantarki a tsayayye jihar Eocp.Kafin yuwuwar sharewa, da electrodes kasance a cikin bude-circuit yanayin sa'an nan da darajar da aka kai tsaye a cikin yanayin da'irar. 5 V vs. Eocp a ƙimar sikanin 0.166 mV / s. Kowane gwaji an maimaita sau 3 tare da kuma ba tare da P. aeruginosa ba.
An goge samfurori don nazarin metallographic da inji tare da 2000 grit rigar SiC takarda sannan kuma a kara gogewa tare da 0.05 μm Al2O3 foda dakatarwa don kallon gani.
Bayan shiryawa, an wanke samfurori sau 3 tare da phosphate-buffered saline (PBS) bayani (pH 7.4 ± 0.2) sa'an nan kuma gyarawa tare da 2.5% (v / v) glutaraldehyde don 10 hours don gyara biofilms. An daga baya dehydrated tare da wani graded jerin (50%, 7% 0, 0,0 9% 90% 90% 90 90% glutaraldehyde). %. don auna zurfin ramin.Domin lura da ramukan lalata da ke ƙarƙashin biofilm, an fara tsabtace yanki na gwaji bisa ga ka'idar kasa ta Sin (CNS) GB/T4334.4-2000 don cire samfuran lalata da biofilm a saman ɓangaren gwajin.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 surface analysis tsarin, Thermo VG, USA) bincike da aka yi amfani da monochromatic X-ray Madogararsa (aluminum Kα line a 1500 eV makamashi da 150 W ikon) a kan wani m dauri makamashi kewayon 0 a karkashin misali yanayi -1350 eV.High-ƙududduka eV spectra da aka rubuta ta amfani da e-masu girma da girma spectra.
An cire samfuran da aka haɗa da su kuma an wanke su a hankali tare da PBS (pH 7.4 ± 0.2) don 15 s45. Don lura da yiwuwar ƙwayoyin cuta na biofilms a kan samfurori, an yi amfani da kwayoyin halitta ta hanyar amfani da LIVE / DEAD BacLight BacLight Viability Kit (Invitrogen, ORes USA, koren Fluescent biyu). -9 dye da jan fluorescent propidium iodide (PI) dye.A ƙarƙashin CLSM, ɗigo tare da kore mai haske da ja suna wakiltar raye-raye masu rai da matattu, bi da bi.Domin lalatawa, cakuda 1 ml wanda ke dauke da 3 μl SYTO-9 da 3 μl PI bayani an sanya shi don minti 20 a cikin dakin da zafin jiki (23. oC) a cikin duhu 8 da aka lura a cikin yanayin zafi (23. oC). nm don sel masu rai da 559 nm don matattun ƙwayoyin cuta) ta amfani da injin Nikon CLSM (C2 Plus, Nikon, Japan) .Biofilm kauri an auna shi a cikin yanayin sikanin 3-D.
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Shi, X., Avci, R., Geiser, M. & Lewandowski, Z. Nazarin Sinadarai na Kwatancen na Microbial da Electrochemically Induced Pitting Corrosion a cikin 316L Bakin Karfe.coros.science.45, 2577-2595 (2003).
Luo, H., Dong, CF, Li, XG & Xiao, K. Electrochemical hali na 2205 duplex bakin karfe a alkaline mafita na daban-daban pH a gaban chloride.Electrochim.Journal.64, 211-220 (2012).
Little, BJ, Lee, JS & Ray, RI Tasirin biofilms na ruwa akan lalata: taƙaitaccen bita.Electrochim.Journal.54, 2-7 (2008).