Corrosion Microbial na 2707 Super Duplex Bakin Karfe na Pseudomonas aeruginosa Marine Biofilm

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Lalata ƙananan ƙwayoyin cuta (MIC) babbar matsala ce a masana'antu da yawa, saboda yana iya haifar da asarar tattalin arziki mai yawa.Super duplex bakin karfe 2707 (2707 HDSS) ana amfani dashi a cikin mahalli na ruwa saboda kyakkyawan juriyar sinadarai.Koyaya, juriyarta ga MIC ba a gwada gwaji ba.Wannan binciken yayi nazarin halin MIC 2707 HDSS wanda kwayar cutar aerobic ta teku ta haifar da Pseudomonas aeruginosa.Binciken Electrochemical ya nuna cewa a gaban Pseudomonas aeruginosa biofilm a cikin matsakaicin 2216E, wani canji mai kyau a cikin yuwuwar lalata da haɓakar haɓakar lalata na yanzu yana faruwa.Binciken X-ray photoelectron spectroscopy (XPS) ya nuna raguwar abun ciki na Cr a saman samfurin a ƙarƙashin biofilm.Binciken gani na ramukan ya nuna cewa P. aeruginosa biofilm ya samar da matsakaicin zurfin rami na 0.69 µm a cikin kwanakin 14 na shiryawa.Ko da yake wannan ƙananan 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 saboda cikakken hade da kyau kwarai inji Properties da lalata juriya1,2.Duk da haka, har yanzu rami na cikin gida yana faruwa kuma yana shafar amincin wannan ƙarfe3,4.DSS ba ta da juriya ga lalatawar ƙananan ƙwayoyin cuta (MIC) 5,6.Duk da fa'idar aikace-aikacen DSS, har yanzu akwai wuraren da juriya na lalata DSS bai isa don amfani na dogon lokaci ba.Wannan yana nufin cewa ana buƙatar kayan da suka fi tsada tare da juriya mafi girma.Jeon et al7 ya gano cewa ko da super duplex bakin karfe (SDSS) suna da wasu iyakoki dangane da juriya na lalata.Don haka, a wasu lokuta, ana buƙatar super duplex bakin karfe (HDSS) tare da mafi girman juriya na lalata.Wannan ya haifar da haɓaka HDSS mai ƙarfi sosai.
Juriya na lalata DSS ya dogara da rabon matakan alpha da gamma kuma ya ƙare a yankuna Cr, Mo da W 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 ƙima mai girma (45-50) na daidai lambar juriya (PREN) wanda aka ƙaddara ta wt.% Cr + 3.3 (wt.% Mo + 0.5 wt. % W) + 16% wt.N12.Kyakkyawan juriya na lalata ya dogara da daidaitaccen abun da ke ƙunshe da kusan 50% ferritic (α) da 50% austenitic (γ).HDSS yana da ingantattun kaddarorin inji kuma mafi girman juriya ga lalata chloride.Ingantattun juriya na lalata yana ƙara amfani da HDSS a cikin ƙarin mahalli na chloride mai ƙarfi kamar yanayin ruwa.
MICs babbar matsala ce a masana'antu da yawa kamar masana'antar mai da iskar gas da na ruwa14.MIC yana da kashi 20% na duk lalacewar lalacewa15.MIC lalata ce ta bioelectrochemical wacce za'a iya lura da ita a wurare da yawa.Biofilms da ke tasowa akan saman ƙarfe suna canza yanayin yanayin lantarki, ta haka yana shafar tsarin lalata.An yi imanin cewa lalatawar MIC ta haifar da biofilms.Electrogenic microorganisms suna cinye karafa don samun kuzarin da suke buƙata don rayuwa17.Nazarin MIC na baya-bayan nan sun nuna cewa EET (canja wurin wutar lantarki na waje) shine ƙayyadaddun ƙayyadaddun ƙimar ƙimar a cikin MIC da ƙwayoyin ƙwayoyin cuta ke haifar da su.Zhang et al.18 ya nuna cewa masu shiga tsakani na lantarki suna hanzarta canja wurin electrons tsakanin kwayoyin Desulfovibrio sessificans da 304 bakin karfe, wanda ya haifar da mummunan harin MIC.Anning et al.19 da Wenzlaff et al.20 sun nuna cewa biofilms na ƙwayoyin cuta masu rage sulfate (SRBs) na iya ɗaukar electrons kai tsaye daga abubuwan ƙarfe na ƙarfe, wanda ke haifar da rami mai tsanani.
DSS an san yana da saukin kamuwa da MIC a cikin kafofin watsa labarai da ke dauke da SRBs, ƙwayoyin cuta masu rage baƙin ƙarfe (IRBs), da sauransu 21.Waɗannan ƙwayoyin cuta suna haifar da ramukan gida a saman DSS a ƙarƙashin biofilms22,23.Ba kamar DSS ba, HDSS24 MIC ba a san shi sosai ba.
Pseudomonas aeruginosa wata kwayar cuta ce ta Gram-korau, mai motsi, kwaya mai siffa ta sanda wacce ta yadu a cikin yanayi25.Pseudomonas aeruginosa kuma babban rukuni ne na ƙananan ƙwayoyin cuta a cikin yanayin ruwa, yana haifar da haɓakar matakan MIC.Pseudomonas yana da hannu sosai a cikin tsarin lalata kuma an gane shi a matsayin majagaba mai mulkin mallaka yayin ƙirƙirar biofilm.Mahat et al.28 da Yuan et al.29 ya nuna cewa Pseudomonas aeruginosa yana kula da haɓaka ƙimar ƙarancin ƙarfe da gami a cikin yanayin ruwa.
Babban makasudin wannan aikin shine don bincika kaddarorin MIC 2707 HDSS da ke haifar da kwayar cutar aerobic na ruwa Pseudomonas aeruginosa ta amfani da hanyoyin electrochemical, hanyoyin bincike na sama da kuma nazarin samfuran lalata.Nazarin electrochemical, gami da yuwuwar kewayawa (OCP), juriya na polarization na layi (LPR), ƙirar ƙirar lantarki (EIS), da yuwuwar polarization mai ƙarfi, an yi don nazarin halayen MIC 2707 HDSS.An gudanar da bincike na tarwatsa makamashi (EDS) don gano abubuwan sinadarai a kan wani gurɓataccen wuri.Bugu da ƙari, an yi amfani da X-ray photoelectron spectroscopy (XPS) don ƙayyade kwanciyar hankali na fim din oxide a ƙarƙashin rinjayar yanayin ruwa mai dauke da Pseudomonas aeruginosa.An auna zurfin ramukan a ƙarƙashin na'urar sikelin Laser mai ɗaukar hoto (CLSM).
Shafin 1 yana nuna nau'in sinadarai na 2707 HDSS.Tebur na 2 ya nuna cewa 2707 HDSS yana da kyawawan kaddarorin inji tare da ƙarfin yawan amfanin ƙasa na 650 MPa.A kan fig.1 yana nuna microstructure na gani na maganin zafi da aka bi da 2707 HDSS.A cikin microstructure dauke da kusan 50% austenite da 50% ferrite matakai, elongated makada na austenite da ferrite matakai ba tare da sakandare matakai suna bayyane.
A kan fig.2a yana nuna yuwuwar buɗaɗɗen kewayawa (Eocp) tare da lokacin bayyanawa don 2707 HDSS a cikin 2216E abiotic matsakaici da P. aeruginosa broth na kwanaki 14 a 37°C.Ya nuna cewa mafi girma kuma mafi girman canji a cikin Eocp yana faruwa a cikin sa'o'i 24 na farko.Ma'auni na Eocp a cikin duka biyun sun haura a -145 mV (idan aka kwatanta da SCE) a kusa da 16 h sannan kuma sun ragu sosai, sun kai -477 mV (idan aka kwatanta da SCE) da -236 mV (idan aka kwatanta da SCE) don samfurin abiotic.da Pseudomonas aeruginosa takardun shaida, bi da bi).Bayan sa'o'i 24, ƙimar Eocp 2707 HDSS na P. aeruginosa ya kasance mai inganci a -228 mV (idan aka kwatanta da SCE), yayin da ƙimar da ba ta dace da samfurorin halittu ba ta kasance kusan -442 mV (idan aka kwatanta da SCE).Eocp a gaban P. aeruginosa ya yi ƙasa sosai.
Nazarin 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.
Tebu na 3 yana nuna ma'aunin lalata electrochemical na samfuran 2707 HDSS da aka fallasa ga abiotic da Pseudomonas aeruginosa inoculated kafofin watsa labarai a cikin tsawon kwanaki 14.An fitar da tangents na anode da cathode masu lankwasa don samun intersections bada lalata halin yanzu yawa (icorr), lalata m (Ecorr) da Tafel gangara (βα da βc) bisa ga daidaitattun hanyoyin30,31.
Kamar yadda aka nuna a cikin fig.2b, haɓakar haɓakawa a cikin madaidaicin P. aeruginosa ya haifar da karuwa a cikin Ecorr idan aka kwatanta da yanayin abiotic.Ƙimar icorr, wanda ya dace da ƙimar lalacewa, ya karu zuwa 0.328 µA cm-2 a cikin samfurin Pseudomonas aeruginosa, wanda ya ninka sau hudu fiye da samfurin da ba na halitta ba (0.087 µA cm-2).
LPR hanya ce ta gargajiya wacce ba ta lalata wutar lantarki don saurin bincike na lalata.An kuma yi amfani da shi don nazarin MIC32.A kan fig.2c yana nuna juriya na polarization (Rp) azaman aikin lokacin fallasa.Ƙimar Rp mafi girma yana nufin ƙarancin lalata.A cikin sa'o'i 24 na farko, Rp 2707 HDSS ya kai kololuwa a 1955 kΩ cm2 don samfuran abiotic da 1429 kΩ cm2 don samfuran Pseudomonas aeruginosa.Hoto na 2c kuma ya nuna cewa ƙimar Rp ta ragu da sauri bayan kwana ɗaya sannan ta kasance ba ta canzawa cikin kwanaki 13 masu zuwa.Ƙimar Rp na samfurin Pseudomonas aeruginosa yana kusan 40 kΩ cm2, wanda ya fi ƙasa da ƙimar 450 kΩ cm2 na samfurin da ba na halitta ba.
Darajar icorr yayi daidai da daidaitaccen adadin lalata.Ana iya ƙididdige ƙimarta daga ma'aunin Stern-Giri mai zuwa:
A cewar Zoe et al.33, ƙimar ƙimar Tafel gangaren B a cikin wannan aikin an ɗauke shi zuwa 26 mV/dec.Hoto na 2d ya nuna cewa icorr na samfurin 2707 ba na halitta ba ya kasance da kwanciyar hankali, yayin da samfurin P. aeruginosa ya canza sosai bayan sa'o'i 24 na farko.Ƙimar icorr na samfuran P. aeruginosa sun kasance tsari mai girma fiye da waɗanda ba na ilimin halitta ba.Wannan yanayin ya yi daidai da sakamakon juriya na polarization.
EIS wata hanya ce wacce ba ta lalacewa da ake amfani da ita don siffanta halayen halayen lantarki akan ruɓatattun saman.Impedance spectra da ƙididdige ƙimar ƙarfin samfuran samfuran da aka fallasa zuwa yanayin abiotic da Pseudomonas aeruginosa bayani, fim ɗin m / biofilm juriya Rb da aka kafa akan saman samfurin, juriya juriya Rct, wutar lantarki biyu Layer capacitance Cdl (EDL) da madaidaicin sigogin kashi na QCPE. (CPE).An kara nazarin waɗannan sigogi ta hanyar dacewa da bayanai ta amfani da samfurin da'ira (EEC).
A kan fig.3 yana nuna makircin Nyquist na al'ada (a da b) da makircin Bode (a' da b') don samfuran HDSS 2707 a cikin kafofin watsa labarai na abiotic da P. aeruginosa broth don lokuta daban-daban.Diamita na zoben Nyquist yana raguwa a gaban Pseudomonas aeruginosa.Makircin Bode (Hoto 3b') yana nuna haɓakar jimlar rashin ƙarfi.Za'a iya samun bayanai game da kullun lokacin hutu daga lokaci maxima.A kan fig.4 yana nuna tsarin jiki wanda ya danganci monolayer (a) da bilayer (b) da EECs masu dacewa.An gabatar da CPE a cikin samfurin EEC.An bayyana shigar da ita da kuma impedance kamar haka:
Samfuran jiki guda biyu da daidaitattun da'irori masu dacewa don dacewa da bakan impedance na samfurin 2707 HDSS:
inda Y0 shine ƙimar KPI, j shine lambar hasashe ko (-1)1/2, ω shine mitar angular, n shine ma'aunin ƙarfin KPI ƙasa da ɗaya35.Juriya juriya na caji (watau 1/Rct) yayi daidai da ƙimar lalata.Karamin Rct, mafi girman ƙimar lalata27.Bayan kwanaki 14 na shiryawa, samfuran Rct na Pseudomonas aeruginosa sun kai 32 kΩ cm2, wanda ya fi ƙasa da 489 kΩ cm2 na samfuran marasa ilimin halitta (Table 4).
Hotunan CLSM da hotunan SEM a cikin Hoto 5 sun nuna a sarari cewa rufin biofilm a saman samfurin HDSS 2707 bayan kwanaki 7 yana da yawa.Koyaya, bayan kwanaki 14, ɗaukar hoto na biofilm ba shi da kyau kuma wasu matattu sun bayyana.Shafin 5 yana nuna kauri na biofilm akan samfuran 2707 HDSS bayan bayyanar P. aeruginosa na kwanaki 7 da 14.Matsakaicin kauri na biofilm ya canza daga 23.4 µm bayan kwanaki 7 zuwa 18.9 µm bayan kwanaki 14.Matsakaicin kauri na biofilm shima ya tabbatar da wannan yanayin.Ya ragu daga 22.2 ± 0.7 μm bayan kwanaki 7 zuwa 17.8 ± 1.0 μm bayan kwanaki 14.
(a) Hoton 3-D CLSM a kwanaki 7, (b) Hoton 3-D CLSM a kwanaki 14, (c) Hoton SEM a kwanaki 7, da (d) Hoton SEM a kwanaki 14.
EMF ya bayyana abubuwan sinadarai a cikin biofilms da samfuran lalata akan samfuran da aka fallasa zuwa P. aeruginosa na kwanaki 14.A kan fig.Hoto na 6 ya nuna cewa abubuwan da ke cikin C, N, O, da P a cikin biofilms da samfuran lalata sun fi girma fiye da tsaftataccen ƙarfe, tunda waɗannan abubuwan suna da alaƙa da biofilms da metabolites.Kwayoyin cuta suna buƙatar kawai gano adadin chromium da baƙin ƙarfe.Babban matakan Cr da Fe a cikin biofilm da samfuran lalata a saman samfuran suna nuna cewa matrix na ƙarfe ya rasa abubuwa saboda lalata.
Bayan kwanaki 14, an lura da ramuka tare da kuma ba tare da P. aeruginosa a cikin matsakaici 2216E.Kafin incubation, saman samfuran ya kasance santsi kuma mara lahani (Fig. 7a).Bayan ƙaddamarwa da kuma cire samfuran biofilm da lalata, an bincika ramuka mafi zurfi a saman samfuran ta amfani da CLSM, kamar yadda aka nuna a cikin siffa 7b da c.Ba a sami fayyace rami a saman abubuwan da ba na halitta ba (mafi girman zurfin rami 0.02 µm).Matsakaicin zurfin rami da P. aeruginosa ya haifar shine 0.52 µm a kwanakin 7 da 0.69 µm a kwanakin 14, dangane da matsakaicin matsakaicin zurfin rami daga samfuran 3 (an zaɓi mafi girman zurfin rami na 10 don kowane samfurin).Nasarar 0.42 ± 0.12 µm da 0.52 ± 0.15 µm, bi da bi (Table 5).Waɗannan ƙimar zurfin rami ƙanana ne amma mahimmanci.
(a) kafin fallasa, (b) kwanaki 14 a cikin yanayin abiotic, da (c) kwanaki 14 a cikin Pseudomonas aeruginosa broth.
A kan fig.Shafin 8 yana nuna nau'in XPS na nau'i-nau'i daban-daban na samfurori, kuma an taƙaita abubuwan sinadaran da aka bincikar don kowane wuri a cikin Table 6. A cikin Table 6, adadin atomic na Fe da Cr a gaban P. aeruginosa (samfurori A da B) sun kasance. ya yi ƙasa da na waɗanda ba na ilimin halitta ba.(misali C da D).Don samfurin P. aeruginosa, madaidaicin tsinkaya a matakin Cr 2p nucleus an haɗa shi zuwa sassa hudu mafi girma tare da makamashi mai ɗaure (BE) na 574.4, 576.6, 578.3 da 586.8 eV, wanda za'a iya dangana ga Cr, Cr2O3, CrO .da Cr (OH) 3, bi da bi (Fig. 9a da b).Don samfuran da ba na halitta ba, bakan babban matakin Cr 2p ya ƙunshi manyan kololuwa biyu don Cr (573.80 eV don BE) da Cr2O3 (575.90 eV don BE) a cikin Figs.9c da d, bi da bi.Bambanci mafi ban mamaki tsakanin samfurori na abiotic da samfurori na P. aeruginosa shine kasancewar Cr6 + da mafi girman dangi na Cr (OH) 3 (BE 586.8 eV) a ƙarƙashin biofilm.
Faɗin XPS na saman samfurin 2707 HDSS a cikin kafofin watsa labarai guda biyu sune kwanaki 7 da 14, bi da bi.
(a) Kwanaki 7 bayyanar P. aeruginosa, (b) kwana 14 bayyanar P. aeruginosa, (c) kwanaki 7 a cikin yanayin abiotic, da (d) kwanaki 14 a cikin yanayin abiotic.
HDSS yana nuna babban matakin juriya na lalata a yawancin mahalli.Kim et al.2 ya ruwaito cewa an gano HDSS UNS S32707 a matsayin DSS mai haɗaka sosai tare da PREN fiye da 45. Ƙimar PREN samfurin 2707 HDSS a cikin wannan aikin shine 49. Wannan shi ne saboda babban abun ciki na chromium da babban abun ciki na molybdenum da nickel, waɗanda suke da amfani a cikin yanayin acidic.da mahalli mai babban abun ciki na chloride.Bugu da ƙari, ƙayyadaddun ma'auni mai kyau da ƙananan ƙwayoyin cuta marasa lahani suna da amfani ga kwanciyar hankali na tsari 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 P. aeruginosa biofilm MICs.
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 yanayin da ba na halitta ba.A cikin Hoto 2a, an sami raguwar Eocp duka a cikin matsakaicin abiotic da a cikin P. aeruginosa broth a cikin sa'o'i 24 na farko.Bayan haka, biofilm ya rufe saman samfurin gaba ɗaya, kuma Eocp ya zama ɗan kwanciyar hankali36.Koyaya, matakin Eocp na halitta ya fi girma fiye da matakin Eocp mara ilimin halitta.Akwai dalilai da za a yi imani da cewa wannan bambanci yana hade da samuwar P. aeruginosa biofilms.A kan fig.2d a gaban P. aeruginosa, icorr 2707 HDSS darajar ya kai 0.627 μA cm-2, wanda shine tsari na girma fiye da na sarrafa abiotic (0.063 μA cm-2), wanda ya dace da ƙimar Rct da aka auna. ta EIS.A cikin 'yan kwanaki na farko, ƙimar impedance a cikin broth P. aeruginosa ya karu saboda haɗewar ƙwayoyin P. aeruginosa da samuwar biofilms.Duk da haka, lokacin da biofilm gaba ɗaya ya rufe samfurin samfurin, raguwa yana raguwa.An kai hari kan Layer na kariya da farko saboda samuwar biofilms da biofilm metabolites.Sakamakon haka, juriya na lalata ya ragu a tsawon lokaci kuma abin da aka makala na P. aeruginosa ya haifar da lalatawar gida.Halin yanayin abiotic ya bambanta.Rashin juriya na lalacewa na kulawar da ba na halitta ba ya fi girma fiye da daidaitattun samfurori da aka fallasa zuwa P. aeruginosa broth.Bugu da ƙari, don haɓakar abiotic, ƙimar Rct 2707 HDSS ta kai 489 kΩ cm2 a ranar 14, wanda shine sau 15 mafi girma fiye da ƙimar Rct (32 kΩ cm2) a gaban P. aeruginosa.Don haka, 2707 HDSS yana da kyakkyawan juriya na lalata a cikin yanayi mara kyau, amma baya jure wa MICs daga P. aeruginosa biofilms.
Hakanan za'a iya lura da waɗannan sakamakon daga maƙallan polarization a cikin figs.2b.An haɗa reshen Anodic tare da Pseudomonas aeruginosa biofilm samuwar da kuma halayen oxidation na ƙarfe.A wannan yanayin, halayen cathodic shine raguwar oxygen.Kasancewar P. aeruginosa yana haɓaka haɓakar lalata na yanzu, game da tsari na girma sama da na sarrafa abiotic.Wannan yana nuna cewa P. aeruginosa biofilm yana haɓaka lalata na gida na 2707 HDSS.Yuan et al.29 sun gano cewa yawan lalata na yanzu na Cu-Ni 70/30 gami ya karu a ƙarƙashin aikin P. aeruginosa biofilm.Wannan na iya zama saboda biocatalysis na rage oxygen ta hanyar Pseudomonas aeruginosa biofilms.Wannan abin lura yana iya yin bayanin MIC 2707 HDSS a cikin wannan aikin.Hakanan ana iya samun ƙarancin iskar oxygen a ƙarƙashin biofilms na aerobic.Saboda haka, ƙin sake ƙetare saman ƙarfe tare da iskar oxygen na iya zama abin da ke ba da gudummawa ga MIC a cikin wannan aikin.
Dickinson et al.38 ya ba da shawarar cewa ƙimar sinadarai da halayen halayen lantarki na iya shafar kai tsaye ta hanyar aikin rayuwa na ƙwayoyin cuta na sessile akan saman samfurin da yanayin samfuran lalata.Kamar yadda aka nuna a cikin Hoto na 5 da Table 5, adadin kwayoyin halitta da kauri na biofilm sun ragu bayan kwanaki 14.Ana iya bayyana wannan da kyau ta gaskiyar cewa bayan kwanaki 14, yawancin ƙwayoyin sessile a saman 2707 HDSS sun mutu saboda ƙarancin abinci mai gina jiki a cikin matsakaicin 2216E ko sakin ions ƙarfe masu guba daga matrix HDSS 2707.Wannan iyakance ne na gwaje-gwajen tsari.
A cikin wannan aikin, P. aeruginosa biofilm ya ba da gudummawa ga raguwar gida na Cr da Fe a ƙarƙashin biofilm a kan 2707 HDSS (Fig. 6).Shafin 6 yana nuna raguwa a cikin 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 ci gaba da kasancewa na farko na kwanaki 7.Ana amfani da yanayin 2216E don daidaita yanayin ruwa.Ya ƙunshi 17700 ppm Cl-, wanda yayi daidai da abin da ke cikin ruwa na teku.Kasancewar 17700 ppm Cl- shine babban dalilin raguwar Cr a cikin samfuran abiotic na kwanaki 7 da 14 da XPS suka bincika.Idan aka kwatanta da samfuran P. aeruginosa, narkar da Cr a cikin samfuran abiotic ya ragu sosai saboda ƙarfin juriya na 2707 HDSS zuwa chlorine a ƙarƙashin yanayin abiotic.A kan fig.9 yana nuna kasancewar Cr6+ a cikin fim ɗin wucewa.Yana iya shiga cikin cire chromium daga saman karfe ta hanyar P. aeruginosa biofilms, kamar yadda Chen da Clayton suka ba da shawara.
Saboda girma na kwayan cuta, pH dabi'u na matsakaici kafin da kuma bayan namo sun kasance 7.4 da 8.2, bi da bi.Saboda haka, a ƙasa da P. aeruginosa biofilm, kwayoyin acid lalata ba shi yiwuwa ya ba da gudummawa ga wannan aikin saboda ƙananan pH a cikin matsakaicin matsakaici.pH na matsakaicin kulawar da ba ilimin halitta bai canza sosai ba (daga farkon 7.4 zuwa 7.5 na ƙarshe) yayin lokacin gwajin kwanaki 14.Haɓakawa a cikin pH a cikin tsaka-tsakin inoculation bayan ƙaddamarwa an haɗa shi da aikin rayuwa 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 yi daidai da bayanan lantarki da aka kwatanta a sama.Zurfin rami na 0.69 µm ya fi sau goma ƙasa da ƙimar 9.5 µm da aka ruwaito na 2205 DSS a ƙarƙashin yanayi iri ɗaya.Waɗannan bayanan sun nuna cewa 2707 HDSS yana nuna mafi kyawun juriya ga MIC fiye da 2205 DSS.Wannan bai kamata ya zo da mamaki ba tun da 2707 HDSS yana da matakan Cr mafi girma waɗanda ke ba da tsayin daka, mafi wahala ga lalata P. aeruginosa, kuma saboda daidaitaccen tsarin sa ba tare da hazo na biyu mai cutarwa ba yana haifar da rami.
A ƙarshe, an samo ramukan MIC a saman 2707 HDSS a cikin P. aeruginosa broth idan aka kwatanta da ramuka marasa mahimmanci a cikin yanayin abiotic.Wannan aikin ya nuna cewa 2707 HDSS yana da mafi kyawun juriya ga MIC fiye da 2205 DSS, amma ba shi da cikakkiyar kariya ga MIC saboda P. aeruginosa biofilm.Waɗannan sakamakon suna taimakawa wajen zaɓin bakin karfe masu dacewa da tsawon rayuwa don yanayin ruwa.
Coupon na 2707 HDSS wanda Jami'ar Arewa maso Gabas (NEU) Makarantar Metallurgy ta Shenyang, China ta bayar.An nuna ainihin abun da ke ciki na 2707 HDSS a cikin Tebur 1, wanda Sashen Gwaji da Nazarin Kayayyakin NEU suka bincika.Dukkan samfuran an bi da su don ingantaccen bayani a 1180 ° C na awa 1.Kafin gwajin lalata, an goge wani nau'in tsabar kuɗi 2707 HDSS tare da saman buɗaɗɗen fili na 1 cm2 zuwa 2000 grit tare da yashi na silicon carbide sannan kuma an goge shi da 0.05 µm Al2O3 foda slurry.Ana kiyaye tarnaƙi da ƙasa tare da fenti marar amfani.Bayan bushewa, an wanke samfurori tare da ruwa mai tsabta mai tsabta da kuma haifuwa tare da 75% (v / v) ethanol don 0.5 h.Sannan an bushe su da iska a ƙarƙashin hasken ultraviolet (UV) na sa'o'i 0.5 kafin amfani.
Marine Pseudomonas aeruginosa iri MCCC 1A00099 an siyi shi ne daga cibiyar tattara al'adun ruwa ta Xiamen (MCCC), China.Pseudomonas aeruginosa an girma a ƙarƙashin yanayin aerobic a 37 ° C. a cikin 250 ml flasks da 500 ml gilashin electrochemical Kwayoyin amfani Marine 2216E ruwa matsakaici (Qingdao Hope Biotechnology Co., Ltd., Qingdao, China).Matsakaici ya ƙunshi: 19.45 Nacl, 5.98 MGCl2, 1.05 SRCB2, 0.08 SRCB2, 0.08 SRCB2, 0.08 cire yisti da 0.1 baƙin ƙarfe citrate.Autoclave a 121 ° C na minti 20 kafin inoculation.Ƙirƙiri sessile da sel planktonic tare da hemocytometer ƙarƙashin ma'aunin haske a girman girman 400x.Matsakaicin farko na Pseudomonas aeruginosa na planktonic nan da nan bayan allurar ya kai kusan sel 106/ml.
An gudanar da gwaje-gwajen lantarki a cikin tantanin halitta na gilashin lantarki na yau da kullun tare da matsakaicin girma na 500 ml.Takardun platinum da cikakken calomel electrode (SAE) an haɗa su da reactor ta hanyar Luggin capillaries cike da gadoji na gishiri, waɗanda ke aiki azaman na'urorin lantarki da na'urori, bi da bi.Don kera na'urorin lantarki masu aiki, an haɗa wayar tagulla mai rubberized zuwa kowane samfurin kuma an rufe shi da resin epoxy, yana barin kusan 1 cm2 na yanki mara kariya don lantarki mai aiki a gefe ɗaya.A lokacin ma'auni na electrochemical, an sanya samfurori a cikin matsakaici na 2216E kuma an ajiye su a cikin zafin jiki na yau da kullum (37 ° C) a cikin wanka na ruwa.An auna OCP, LPR, EIS da yuwuwar bayanan polarization mai ƙarfi ta amfani da Autolab potentiostat (Reference 600TM, Gamry Instruments, Inc., Amurka).An yi rikodin gwaje-gwajen LPR a ƙimar sikanin 0.125 mV s-1 a cikin kewayon -5 zuwa 5 mV tare da Eocp da ƙimar samfurin 1 Hz.An yi EIS tare da igiyar ruwa ta sine akan kewayon mitar 0.01 zuwa 10,000 Hz ta amfani da ƙarfin lantarki da aka yi amfani da shi na 5 mV a tsayayyen Eocp.Kafin yuwuwar sharewa, wayoyin lantarki suna cikin yanayin zaman banza har sai an kai ga daidaiton ƙimar yuwuwar lalatawa.Daga nan an auna magudanar ruwa daga -0.2 zuwa 1.5 V a matsayin aikin Eocp a ƙimar sikanin 0.166 mV/s.Kowane gwaji an maimaita sau 3 tare da kuma ba tare da P. aeruginosa ba.
Samfurori don nazarin metallographic an goge su da injina tare da rigar 2000 grit SiC takarda sannan kuma a kara gogewa tare da dakatarwar foda na 0.05 µm Al2O3 don kallon gani.An gudanar da bincike na metallographic ta amfani da na'urar gani da ido.Samfurori an kwafe su da 10 wt% bayani na potassium hydroxide 43.
Bayan shiryawa, an wanke samfurori sau 3 tare da phosphate buffered saline (PBS) (pH 7.4 ± 0.2) sannan kuma an gyara shi tare da 2.5% (v / v) glutaraldehyde na 10 hours don gyara biofilms.Daga nan sai a shayar da shi da sinadarin ethanol (50%, 60%, 70%, 80%, 90%, 95% and 100% by volume) kafin iska ta bushe.A ƙarshe, an ajiye fim ɗin zinari a saman samfurin don samar da ƙaddamarwa don kallon SEM.Hotunan SEM sun mayar da hankali kan tabo tare da mafi yawan kwayoyin halitta P. aeruginosa a saman kowane samfurin.Yi nazarin EDS don nemo abubuwan sinadarai.An yi amfani da microscope na Laser confocal confocal (CLSM) (LSM 710, Zeiss, Jamus) don auna zurfin rami.Don lura da ramukan lalata a ƙarƙashin biofilm, samfurin gwajin an fara tsaftace shi bisa ga ka'idar kasa ta Sin (CNS) GB/T4334.4-2000 don cire samfuran lalata da biofilm daga saman samfurin gwajin.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 tsarin nazarin sararin samaniya, Thermo VG, Amurka) an gudanar da bincike ta amfani da tushen X-ray na monochromatic (layin Aluminum Kα tare da makamashi na 1500 eV da ikon 150 W) a cikin kewayon da yawa. dauri makamashi 0 a karkashin daidaitattun yanayi na -1350 eV.An yi rikodin bakan ƙuduri mai girma ta amfani da ƙarfin watsawa na 50 eV da mataki na 0.2 eV.
An cire samfuran da aka haɗa kuma an wanke su a hankali tare da PBS (pH 7.4 ± 0.2) don 15 s45.Don lura da yuwuwar ƙwayoyin cuta na biofilms akan samfuran, samfuran biofilms an lalata su ta amfani da LIVE/DEAD BacLight BacLight Viability Kit (Invitrogen, Eugene, OR, Amurka).Kit ɗin ya ƙunshi rini mai kyalli guda biyu: SYTO-9 kore mai kyalli da kuma propidium iodide (PI) rini mai kyalli.A cikin CLSM, dige-dige kore da jajayen ɗigo suna wakiltar sel masu rai da matattu, bi da bi.Don tabo, 1 ml na cakuda mai dauke da 3 µl na SYTO-9 da 3 µl na maganin PI an shirya shi na mintuna 20 a zazzabi na ɗaki (23°C) a cikin duhu.Bayan haka, an gwada samfuran tabo a tsayi biyu (488 nm don sel masu rai da 559 nm don matattun ƙwayoyin cuta) ta amfani da na'urar Nikon CLSM (C2 Plus, Nikon, Japan).An auna kauri na biofilm a yanayin sikanin 3D.
Yadda za a buga wannan labarin: Li, H. et al.Lalacewar Microbial na 2707 super duplex bakin karfe ta Pseudomonas aeruginosa marine biofilm.ilimin kimiyya.6, 20190. doi: 10.1038/srep20190 (2016).
Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Stress lalata fatattaka na LDX 2101 duplex bakin karfe a cikin chloride mafita a gaban thiosulphate. Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Stress lalata fatattaka na LDX 2101 duplex bakin karfe a cikin chloride mafita a gaban thiosulphate. Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Коррозионное растрескивание под напряжением дуплексной нержавеющей стали LDX 2101 в растворах хлоридов в присутствии тиосульфата. Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Stress lalata fatattaka duplex bakin karfe LDX 2101 a chloride mafita a gaban thiosulfate. Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. LDX 2101 Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. LDX 2101 双相 bakin karfe在福代 sulfate Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Коррозионное растрескивание под напряжением дуплексной нержавеющей стали LDX 2101 в растворе хлорида в присутствии тиосульфата. Zanotto, F., Grassi, V., Balbo, A., Monticelli, C. & Zucchi, F. Stress lalata fatattaka duplex bakin karfe LDX 2101 a chloride bayani a gaban thiosulfate.coros science 80, 205-212 (2014).
Kim, ST, Jang, SH, Lee, IS & Park, YS Tasirin maganin zafi-jiyya da nitrogen a cikin garkuwar iskar gas akan juriya ga gurɓacewar iska na hyper duplex bakin ƙarfe welds. Kim, ST, Jang, SH, Lee, IS & Park, YS Tasirin maganin zafi-jiyya da nitrogen a cikin garkuwar iskar gas akan juriya ga gurɓacewar iska na hyper duplex bakin ƙarfe welds.Kim, ST, Jang, SH, Lee, IS da Park, YS Tasirin ingantaccen maganin zafi mai ƙarfi da nitrogen a cikin garkuwar iskar gas akan juriyar lalatawar hyperduplex bakin ƙarfe welds. Kim, ST, Jang, SH, Lee, IS & Park, Ys Kim, ST, Jang, SH, Lee, IS & Park, YSKim, ST, Jang, SH, Lee, IS da Park, YS Tasirin maganin zafi na maganin zafi da nitrogen a cikin garkuwar iskar gas akan juriyar lalatawar super duplex bakin karfe welds.koros.ilimin kimiyya.53, 1939-1947 (2011).
Shi, X., Avci, R., Geiser, M. & Lewandowski, Z. Nazarin kwatankwacin sinadarai na microbially da electrochemically induced pitting na 316L bakin karfe. Shi, X., Avci, R., Geiser, M. & Lewandowski, Z. Nazarin kwatankwacin sinadarai na microbially da electrochemically induced pitting na 316L bakin karfe.Shi, X., Avchi, R., Geyser, M. da Lewandowski, Z. Kwatanta nazarin sinadarai na microbiological da electrochemical pitting na 316L bakin karfe. Shi, X., Avci, R., Geiser, M. & Lewandowski, Z. 微生物和电化学诱导的316L Shi, X., Avci, R., Geiser, M. & Lewandowski, Z.Shi, X., Avchi, R., Geyser, M. da Lewandowski, Z. Kwatanta nazarin sinadarai na microbiological da electrochemically induced pitting a 316L bakin karfe.koros.ilimin kimiyya.45, 2577-2595 (2003).
Luo, H., Dong, CF, Li, XG & Xiao, K. Halin electrochemical na 2205 duplex bakin karfe a cikin maganin alkaline tare da pH daban-daban a gaban chloride. Luo, H., Dong, CF, Li, XG & Xiao, K. Halin electrochemical na 2205 duplex bakin karfe a cikin maganin alkaline tare da pH daban-daban a gaban chloride.Luo H., Dong KF, Lee HG da Xiao K. Electrochemical hali na duplex bakin karfe 2205 a alkaline mafita tare da daban-daban pH a gaban chloride. Luo, H., Dong, CF, Li, XG & Xiao, K. 2205 Luo, H., Dong, CF, Li, XG & Xiao, K. 2205 Electrochemical hali na 双相 bakin karfe a gaban chloride a daban-daban pH a alkaline bayani.Luo H., Dong KF, Lee HG da Xiao K. Electrochemical hali na duplex bakin karfe 2205 a alkaline mafita tare da daban-daban pH a gaban chloride.Electrochem.Mujallar.64, 211-220 (2012).
Little, BJ, Lee, JS & Ray, RI Tasirin biofilms na ruwa akan lalata: taƙaitaccen bita. Little, BJ, Lee, JS & Ray, RI Tasirin biofilms na ruwa akan lalata: taƙaitaccen bita.Ƙananan, BJ, Lee, JS da Ray, Tasirin RI na Marine Biofilms akan Lalacewa: Takaitaccen Bita. Little, BJ, Lee, JS & Ray, RI 海洋生物膜对腐蚀的影响:简明综述。 Little, BJ, Lee, JS & Ray, RIƘananan, BJ, Lee, JS da Ray, Tasirin RI na Marine Biofilms akan Lalacewa: Takaitaccen Bita.Electrochem.Mujallar.54, 2-7 (2008).


Lokacin aikawa: Oktoba-28-2022