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Microbial corrosion (MIC) bụ nsogbu siri ike n'ọtụtụ ụlọ ọrụ n'ihi na ọ nwere ike ịkpata nnukwu mfu akụ na ụba .2707 super duplex igwe anaghị agba nchara (2707 HDSS) ka ejiri mee ihe na gburugburu mmiri n'ihi nguzogide kemịkalụ ya dị mma. Otú ọ dị, egosiputaghị nguzogide ya na MIC. Nyocha rochemical gosiri na n'ihu Pseudomonas aeruginosa biofilm na 2216E ọkara, enwere mgbanwe dị mma na ikike nke corrosion na mmụba nke corrosion njupụta ugbu a. Nyocha X-ray photoelectron spectroscopy (XPS) gosipụtara mbelata nke ọdịnaya Cr n'elu nke ihe nleba anya n'okpuru pifilm. Imaging nke nyocha nke Pimeru na-emepụta ihe omimi nke biofilm. .69 μm n'ime ụbọchị 14 nke incubation. Ọ bụ ezie na nke a dị ntakịrị, ọ na-egosi na 2707 HDSS adịghị echebe kpamkpam na MIC nke P. aeruginosa biofilms.
Duplex igwe anaghị agba nchara (DSS) na-ọtụtụ ebe na-eji dị iche iche industries n'ihi na ha ezigbo Nchikota magburu onwe n'ibu Njirimara na corrosion resistance1,2.However, localized pitting ka emee na ọ na-emetụta ndị iguzosi ike n'ezi ihe nke a steel3,4.DSS bụ adịghị eguzogide microbial corrosion (MIC) 5,6.N'agbanyeghị na mbara nso nke ngwa nke DSS, na e nwere ndị ọzọ corrosion na-eguzogide n'ihi na gburugburu ebe obibi bụ ogologo oge iji na-eguzogide nke DSS. A na-achọ ihe ndị nwere nguzogide corrosion elu dị elu.Jeon et al7 chọpụtara na ọbụnadị super duplex igwe anaghị agba nchara (SDSS) nwere ụfọdụ njedebe n'ihe gbasara nkwụsị nke corrosion.
Nguzogide corrosion nke DSS na-adabere na nha nke alpha na gamma na mpaghara Cr, Mo na W depleted 8, 9, 10 n'akụkụ akụkụ nke abụọ.HDSS nwere ọdịnaya dị elu nke Cr, Mo na N11, n'ihi ya, ọ nwere nguzogide corrosion magburu onwe ya na uru dị elu (45-50) Pitting Resistance Equivalent kpebisiri ike site na PREN + 3% .wt. %.Njirimara corrosion chloride. Nguzogide corrosion emelitere na-agbasawanye ojiji nke HDSS na gburugburu chloride na-emebi emebi, dị ka gburugburu mmiri.
MIC bụ nnukwu nsogbu n'ọtụtụ ọrụ dị ka mmanụ na gas na mmiri utilities14.MIC na-akpata 20% nke mmebi nke corrosion niile15.MIC bụ bioelectrochemical corrosion nke nwere ike ịhụ na ọtụtụ gburugburu. nweta ume na-adịgide adịgide iji dịrị ndụ17. Nnyocha MIC na nso nso a egosila na EET (nfefe elektrọn ọzọ) bụ ihe na-ebelata ọnụego na MIC nke microorganisms electrogenic na-ebute.Zhang et al.18 gosipụtara na ndị mgbasa ozi elektrọn na-eme ka nnyefe elektrọn dị n'etiti mkpụrụ ndụ Desulfovibrio sessificans na 304 igwe anaghị agba nchara, na-eduga na mwakpo MIC ka njọ.Enning et al.19 na Venzlaff et al.20 gosiri na nje bacteria na-ebelata sulfate na-emebi emebi (SRB) biofilms nwere ike ịmịnye elektrọn ozugbo site na mkpụrụ igwe, na-ebute corrosion siri ike.
A maara DSS na ọ nwere ike ịnweta MIC na gburugburu ebe nwere SRB, nje bacteria na-ebelata ígwè (IRB), wdg.
Pseudomonas aeruginosa bụ gram-adịghị mma motile mkpanaka nke nje bacteria na-ekesa n'ọtụtụ ebe na ọdịdị25.28 na Yuan et al.29 gosipụtara na Pseudomonas aeruginosa nwere ọchịchọ ịbawanye ọnụego corrosion nke ígwè dị nro na alloys na gburugburu mmiri.
Ebumnuche bụ isi nke ọrụ a bụ iji nyochaa njirimara MIC nke 2707 HDSS kpatara site na mmiri aerobic bacterium Pseudomonas aeruginosa site na iji usoro electrochemical, usoro nyocha nke elu na nyocha ngwaahịa corrosion.Electrochemical Studies gụnyere Open Circuit Potential (OCP), Linear Polarization Resistance (LPR), Electroscopy Impedance, Pseudomonas aeruginosa, Pseudomonas Aeruginosa, Pseudomonas Aeruginosa, na Pseudomonas Aeruginosa, na-eme nchọpụta nke Polarization. nke 2707 HDSS.Energy dispersive spectrometer (EDS) analysis e mere iji chọta chemical ọcha n'elu corroded. Tụkwasị na nke a, X-ray photoelectron spectroscopy (XPS) analysis na-eji chọpụta nkwụsi ike nke oxide film passivation n'okpuru mmetụta nke mmiri gburugburu nke nwere Pseudomonas aeruginosa. The olulu mmiri na-enyocha ihe omimi nke laser (CL) na-enyocha ihe omimi nke laser.
Isiokwu 1 depụtara chemical mejupụtara nke 2707 HDSS. Isiokwu 2 na-egosi na 2707 HDSS nwere magburu onwe n'ibu Njirimara na a mkpụrụ ike nke 650 MPa.Figure 1 na-egosi na ngwa anya microstructure nke ngwọta okpomọkụ mesoo 2707 HDSS.Elongated bands nke austenite na ferrite n'ụzọ na-enweghị nke abụọ n'ụzọ nwere ike hụrụ na a na-eme ihe na-adọ% microstrurite 5% microstrurite.
Ọnụ ọgụgụ 2a na-egosi ike imeghe oghere (Eocp) na oge ikpughe data maka 2707 HDSS na abiotic 2216E medium na P. aeruginosa broth maka 14 ụbọchị na 37 Celsius C. Ọ na-egosi na mgbanwe kasị ukwuu na nke dị ịrịba ama na Eocp na-eme n'ime awa 24 mbụ. Ọnụ ahịa Eocp na abụọ ahụ ruru na -145.6 m. 77 mV (vs. SCE) na -236 mV (vs. SCE) maka ihe atụ abiotic na P, n'otu n'otu).Pseudomonas aeruginosa Kupọns, karị. Mgbe awa 24 gasịrị, uru Eocp nke 2707 HDSS maka P. aeruginosa dị ntakịrị na -228 mV (vs. SCE), ebe ọnụ ahịa kwekọrọ na ihe ndị na-abụghị nke ndu bụ ihe dịka -442 mV (vs. SCE) .Eocp na ọnụnọ Po.
Nnwale electrochemical nke ụdị 2707 HDSS n'ime abiotic media na Pseudomonas aeruginosa broth na 37 Celsius C:
(a) Eocp dị ka ọrụ nke oge ikpughe, (b) ntụgharị polarization na ụbọchị 14, (c) Rp dị ka ọrụ nke oge ikpughe na (d) icorr dị ka ọrụ nke oge ikpughe.
Tebụl 3 depụtara ụkpụrụ parameter corrosion electrochemical nke 2707 HDSS sample ekpughere na abiotic medium na Pseudomonas aeruginosa inoculated ọkara maka ụbọchị 14. The tangents nke anodic na cathodic curves e extrapolated na-abata na intersections na-enye corrosion ugbu njupụta ugbu a (icorr), corrosion β na corrosion (corrosion) usoro dị ka corrosion β na usoro. 0,31.
Dị ka e gosiri na foto 2b, ngbanwe nke elu nke P. aeruginosa na-eme ka mmụba na Ecorr jiri ya tụnyere abiotic curve. Ọnụ ahịa icorr, nke kwekọrọ na ọnụ ọgụgụ corrosion, mụbara na 0.328 μA cm-2 na Pseudomonas aeruginosa sample, ugboro anọ karịa ihe atụ nke na-abụghị nke 082 cm. μ.
LPR bụ a classic na-adịghị ebibi electrochemical usoro maka ngwa ngwa corrosion analysis.It na-eji na-amụ MIC32.Figure 2c na-egosi na polarization resistance (Rp) dị ka a ọrụ nke ikpughe time.A elu Rp uru pụtara obere corrosion.N'ime mbụ 24 awa, na Rp nke 2707 HDSS ruru a kacha uru nke 1955 a kΩ Ω Ω Ω Ω 24 sm. aeruginosa samples.Figure 2c na-egosikwa na ọnụ ahịa Rp na-ebelata ngwa ngwa mgbe otu ụbọchị gasịrị wee nọgide na-agbanwe agbanwe maka ụbọchị 13 na-esote. Ọnụ ego Rp nke ihe atụ nke Pseudomonas aeruginosa dị ihe dịka 40 kΩ cm2, nke dị ala karịa 450 kΩ cm2 uru nke ihe nlele na-abụghị nke ndu.
Ọnụ ahịa icorr dabara na ọnụego corrosion otu. Enwere ike gbakọọ ọnụ ahịa ya site na ngụkọ Stern-Geary na-esonụ.
Na-esote Zou et al.33, a ahụkarị uru nke Tafel mkpọda B na ọrụ a chere na-26 mV / dec. Figure 2d na-egosi na icorr nke na-abụghị ndu 2707 sample nọgidere dịtụ kwụsiri ike, mgbe P. aeruginosa sample fluctuated ukwuu mgbe mbụ 24 hours. The icorr ụkpụrụ nke iji iwu magntuni na-emekarị nke P. dabara na nsonaazụ nguzogide polarization.
EIS bụ usoro ọzọ na-adịghị emebi emebi nke a na-eji akọwa mmeghachi omume electrochemical na interfaces corroded. Impedance spectra and gbakọọ capacitance ụkpụrụ nke ihe atụ ekpughere abiotic media na Pseudomonas aeruginosa ngwọta, Rb resistance nke passive film / biofilm kpụrụ n'elu nke ihe atụ, Rct ụgwọ eletriki na-eguzogide okpukpu abụọ, Cd Cd. CPE). A na-enyochakwa ihe ndị a site n'itinye data ahụ site na iji ụdị sekit (EEC).
Ọgụgụ 3 na-egosi ahụkarị Nyquist plots (a na b) na Bode plots (a' na b') nke 2707 HDSS samples na abiotic medium na P. aeruginosa broth maka dị iche iche incubation times.The dayameta nke Nyquist mgbanaka mbelata na ọnụnọ nke Pseudomonas aeruginosa. The Bode ibé (Fig. 3. Mmụba na oge izu ike na ngụkọta oge) nwere ike inye site na-adọ maxima.Figure 4 na-egosi monolayer (a) na bilayer (b) dabeere anụ ahụ owuwu na ha kwekọrọ ekwekọ EECs.CPE ewebata n'ime EEC model.Ya nnabata na impedance na-egosipụta dị ka ndị a:
Modelsdị anụ ahụ abụọ na sekit dabara adaba maka ịkwado ụdịdị impedance nke ụdị 2707 HDSS:
ebe Y0 bụ ịdị ukwuu nke CPE, j bụ nọmba echiche ma ọ bụ (-1) 1/2, ω bụ ugboro ugboro, na n bụ CPE ike index na-erughị ịdị n'otu35. The inverse nke ụgwọ nnyefe eguzogide (ie 1 / Rct) kwekọrọ na corrosion rate. Smaller Rct pụtara ngwa ngwa corrosion rate27, the Rmon the sample in the sample incuudo 27. s ruru 32 kΩ cm2, dị obere karịa 489 kΩ cm2 nke ihe nlele na-abụghị nke ndu (Table 4).
Ihe oyiyi CLSM na ihe oyiyi SEM dị na foto 5 na-egosi n'ụzọ doro anya na mkpuchi biofilm n'elu 2707 HDSS ihe atụ mgbe ụbọchị 7 gasịrị. Otú ọ dị, mgbe ụbọchị 14 gasịrị, ihe mkpuchi biofilm dị ntakịrị na ụfọdụ mkpụrụ ndụ nwụrụ anwụ pụtara. Tebụl 5 na-egosi nha nke biofilm na 2707 HDSS specimens a 7. Mgbanwe nke ukwuu site na nhụsianya nke PIP1. 23.4 μm mgbe ụbọchị 7 gachara ruo 18.9 μm mgbe ụbọchị 14 gasịrị. Nkezi biofilm ọkpụrụkpụ kwenyekwara na nke a na-emekarị.
(a) onyonyo 3-D CLSM mgbe ụbọchị asaa gachara, (b) onyonyo 3-D CLSM ka ụbọchị iri na anọ gachara, (c) onyonyo SEM ka ụbọchị asaa gachara yana (d) onyonyo SEM ka ụbọchị iri na anọ gachara.
EDS kpughere chemical ọcha na biofilms na corrosion ngwaahịa na samples kpughere P. aeruginosa maka ụbọchị 14. Figure 6 na-egosi na ọdịnaya nke C, N, O, P na biofilms na corrosion ngwaahịa bụ nnọọ elu karịa nke ahụ na iferi ọla, n'ihi na ihe ndị a na-ejikọta ya na biofilms na ha metabolites.Microbes naanị mkpa trace ichekwa ngwaahịa na ígwè biofil na elu nke chrome. nke ihe nlere anya na-egosi na matriks metal ahụ furu efu ihe n'ihi corrosion.
Mgbe ụbọchị 14 gasịrị, a na-ahụ pitting na na-enweghị P. aeruginosa na 2216E medium. Tupu ịmalite, ihe atụ ahụ dị n'elu dị nro na enweghị ntụpọ (Fig 7a) . Mgbe mmechi na mwepụ nke biofilm na corrosion ngwaahịa, olulu miri emi dị n'elu nke ihe atụ ahụ, a na-enyocha ya n'okpuru CL. ihe nleba anya nke ndu (oke omimi nke olulu 0.02 μm) . Oke omimi nke Pseudomonas aeruginosa kpatara bụ 0.52 μm mgbe ụbọchị 7 gasịrị na 0.69 μm mgbe ụbọchị 14 gasịrị, dabere na nkezi olulu omimi nke 3 sample (10 kacha elu olulu omimi ụkpụrụ ahọpụtara maka onye ọ bụla. ± 0 ± 2 μm). 15 μm, n'otu n'otu (Table 5) .Ndị a olulu omimi ụkpụrụ dị obere ma dị mkpa.
(a) Tupu ikpughe, (b) ụbọchị iri na anọ n'ime usoro abiotic na (c) ụbọchị iri na anọ na broth Pseudomonas aeruginosa.
Ọgụgụ 8 na-egosi ụdị XPS dị iche iche nke ihe atụ dị iche iche, na ihe mejupụtara kemịkalụ nyochara maka elu ọ bụla na-achikota na tebụl 6. Na tebụl 6, ọnụọgụ atomic nke Fe na Cr n'ihu P. aeruginosa (ihe atụ A na B) dị nnọọ ala karịa nke ndị na-adịghị na-achịkwa ihe ndị na-adịghị ndụ (ihe atụ C na D) .N'ihi na P. tted na anọ ọnụ ọgụgụ kasị elu mmiri na-ekekọta ike (BE) ụkpụrụ nke 574.4, 576.6, 578.3 na 586.8 eV, nke nwere ike ekewet Cr, Cr2O3, CrO3 na Cr (OH) 3, karị (Fig. 9a na b) .N'ihi na ndị na-abụghị ndị ndu, na Cr2O3, Cr. (573.80 eV maka BE) na Cr2O3 (575.90 eV maka BE) na Fig. 9c na d, n'otu n'otu. Ihe dị iche iche dị ịrịba ama n'etiti abiotic na P. aeruginosa samples bụ ọnụnọ nke Cr6 + na ọnụ ọgụgụ dị elu nke Cr (OH) 3 (BE nke 586.8 na biofilm nọ n'okpuru).
Ihe ngosi XPS sara mbara nke elu nke ụdị 2707 HDSS na mgbasa ozi abụọ ahụ bụ ụbọchị 7 na ụbọchị iri na anọ, n'otu n'otu.
(a) Ụbọchị 7 nke ikpughe P. aeruginosa, (b) ụbọchị 14 nke ikpughe P. aeruginosa, (c) ụbọchị 7 n'ime usoro abiotic na (d) ụbọchị 14 n'ime usoro abiotic.
HDSS na-egosipụta ọkwa dị elu nke nguzogide corrosion n'ọtụtụ gburugburu.Kim et al.2 kọrọ na UNS S32707 HDSS kọwara dị ka a ukwuu alloyed DSS na a PREN nke ihe karịrị 45. The PREN uru nke 2707 HDSS specimen na ọrụ a bụ 49. Nke a bụ n'ihi na ya elu chromium ọdịnaya na elu molybdenum na Ni ọkwa, nke bara uru na acidic na elu chloride larịị, bara uru na gburugburu ebe obibi chloride-adịghị arụ ọrụ. Nkwụsi ike nke ural na nguzogide corrosion. Otú ọ dị, n'agbanyeghị ezigbo nguzogide kemịkal ya, data nyocha na ọrụ a na-egosi na 2707 HDSS adịghị egbochi kpamkpam na MIC nke P. aeruginosa biofilms.
Nsonaazụ Electrochemical gosiri na ọnụ ọgụgụ corrosion nke 2707 HDSS na broth P. aeruginosa na-abawanye nke ukwuu mgbe ụbọchị 14 gasịrị ma e jiri ya tụnyere ndị na-abụghị ihe ndị dị ndụ. Na ọnụ ọgụgụ 2a, a na-ahụ mbelata nke Eocp na ma abiotic medium na P. aeruginosa broth n'oge mbụ 24 awa. Mgbe e mesịrị, biofilm emechala ekpuchi elu nke Eocpecip. ological Eocp dị elu karịa nke Eocp na-abụghị nke ndu. E nwere ihe mere ị ga-eji kwere na ọdịiche a bụ n'ihi P. aeruginosa biofilm formation.Na Fig. 2d, n'ihu P. aeruginosa, icorr uru nke 2707 HDSS ruru 0.627 μA cm-2, nke bụ usoro nke na-agbanwe agbanwe nke Magni-0 cm-2, nke bụ usoro nke na-agbanwe agbanwe nke μA cm-2. N'ime ụbọchị ole na ole mbụ, ụkpụrụ impedance na P. aeruginosa broth mụbara n'ihi ntinye nke sel P. aeruginosa na nhazi nke biofilms. Otú ọ dị, mgbe biofilm na-ekpuchi elu nke ihe atụ ahụ kpamkpam, ihe mgbochi ahụ na-ebelata. A na-awakpo oyi akwa mkpuchi nke mbụ n'ihi nkwụsị nke oge na-emepụta ihe na-emepụta biofilm. , na mgbakwunye nke P. aeruginosa mere ka corrosion mpaghara dị iche iche. Ihe na-emekarị na mgbasa ozi abiotic dị iche iche. Nguzogide corrosion nke nchịkwa na-abụghị nke ndu dị elu karịa uru kwekọrọ ekwekọ nke ihe nlele ahụ gosipụtara na broth P. ) n'ihu P. aeruginosa. Ya mere, 2707 HDSS nwere ezigbo nguzogide corrosion na gburugburu ebe obibi na-adịghị mma, ma ọ dịghị eguzogide MIC ọgụ site na P. aeruginosa biofilms.
A pụkwara ịhụ nsonaazụ ndị a site na ọkpụkpụ polarization na Fig 2b. A na-akpọ alaka anodic na Pseudomonas aeruginosa biofilm formation na metal oxidation reactions. N'otu oge ahụ, mmeghachi omume cathodic bụ mbelata oxygen. Ọnụnọ nke P. aeruginosa mụbara corrosion ugbu a njupụta, dị ka ihe dị elu nke na-eme ka a na-eme ka a na-eme ka a na-eme ka a na-eme ka a na-emepụta ihe na-emepụta ihe. Mpaghara corrosion nke 2707 HDSS.Yuan et al29 chọpụtara na njupụta corrosion ugbu a nke 70/30 Cu-Ni alloy mụbara n'okpuru ihe ịma aka nke P. aeruginosa biofilm. Nke a nwere ike ịbụ n'ihi biocatalysis nke oxygen Mbelata site Pseudomonas aeruginosa biofilms. Nke a na-ekiri nwekwara ike na-akọwa na nke a na-arụ ọrụ nke HDA. .Ya mere, ọdịda ịghaghachi n'elu igwe site na ikuku oxygen nwere ike ịbụ ihe na-enye aka na MIC na ọrụ a.
Dickinson et al.38 tụrụ aro na ọnụego nke mmeghachi omume nke kemịkalụ na electrochemical nwere ike imetụta kpọmkwem site na ọrụ metabolic nke sessile bacteria n'elu ihe atụ ahụ na ọdịdị nke ngwaahịa corrosion. Dị ka e gosiri na Figure 5 na Tebụl 5, ma nọmba cell na biofilm ọkpụrụkpụ belatara mgbe 14 days. Nke a nwere ike ezi uche kọwara na mgbe 14 ụbọchị, ọtụtụ n'ime 7 sesent 2 cell nwụrụ na 7 n'elu HD2 sel n'ihi na 7 n'elu sel dessple 2 n'ihi n'ihi na 7 n'elu sel nke HDSSple. 16E ọkara ma ọ bụ ntọhapụ nke ion metal na-egbu egbu site na 2707 HDSS matrix. Nke a bụ njedebe nke nnwale batch.
N'ime ọrụ a, P. aeruginosa biofilm kwalitere mmebi mpaghara nke Cr na Fe n'okpuru biofilm na 2707 HDSS elu (Fig 6) .Na Tebụl 6, Mbelata Fe na Cr na sample D tụnyere C, na-egosi na agbaze Fe na Cr kpatara site na P. nwere 17700 ppm Cl-, nke yiri nke a na-ahụ na mmiri mmiri eke. Ọnụnọ nke 17700 ppm Cl- bụ isi ihe kpatara mbelata Cr na 7- na 14 ụbọchị abiotic samples nke XPS nyochara. Ọnụ ọgụgụ 9 na-egosi ọnụnọ nke Cr6 + na ihe nkiri passivation. Ọ nwere ike itinye aka na mwepụ nke Cr site na nchara ígwè site na P. aeruginosa biofilms, dị ka Chen na Clayton tụrụ aro.
N'ihi na nje ibu, na pH ụkpụrụ nke na-ajụ tupu na mgbe cultivation bụ 7.4 na 8.2, karị.Ya mere, n'okpuru P. aeruginosa biofilm, organic acid corrosion bụ eleghi anya na-eme ka ihe na-enye aka na-arụ ọrụ a n'ihi na dịtụ elu pH na nnukwu medium.The pH nke na-abụghị usoro mgbanwe mgbanwe n'oge 7.4. Oge nyocha nke ụbọchị 14. Mmụba nke pH na usoro inoculation mgbe a na-emepụta ya bụ n'ihi ọrụ metabolic nke P. aeruginosa ma chọpụta na ọ nwere mmetụta dị otú ahụ na pH na-enweghị mpempe ule.
Dị ka e gosiri na foto 7, ihe omimi olulu kachasị nke P. aeruginosa biofilm kpatara bụ 0.69 μm, nke dị nnọọ ukwuu karịa nke abiotic media (0.02 μm) .Nke a kwekọrọ na data electrochemical nke akọwara n'elu. Ihe omimi olulu 0.69 μm karịrị okpukpu iri dị ntakịrị karịa 9.5 μm20 na-egosi data DSS nke dị n'okpuru ọnọdụ 9.5 μm20 na-egosi na DSS. na-egbochi nguzogide MIC ka mma ma e jiri ya tụnyere 2205 DSS. Nke a ekwesịghị ịbụ ihe ijuanya, dị ka 2707 HDSS nwere ọdịnaya chromium dị elu, na-enye ohere na-adịgide adịgide, n'ihi usoro nhazi nke ọma na-enweghị ihe mgbochi nke abụọ na-emerụ ahụ, na-eme ka ọ sie ike maka P. aeruginosa ka ọ ghara ịda mbà ma malite isi n'ehihie.
N'ikpeazụ, a chọtara MIC pitting n'elu 2707 HDSS na P. aeruginosa broth tụnyere negligible pitting na abiotic media.Nke a na-arụ ọrụ na-egosi na 2707 HDSS nwere mma MIC mgbochi karịa 2205 DSS, ma ọ bụghị zuru ezu dịghịzi MIC n'ihi P. aeruginosa biofilm. Ndị a nchoputa nke kwesịrị ekwesị na-arụ ọrụ na igwe anaghị agba nchara.
The coupon maka 2707 HDSS na-nyere Ụlọ Akwụkwọ Metallurgy nke Northeast University (NEU) na Shenyang, China. The elemental mejupụtara nke 2707 HDSS na-egosi na Table 1, nke e nyochara site NEU Materials Analysis and Testing Department. All samples were ngwọta na-emeso na 1180 °C maka 1 hour.Prior ka a na-eme ihe ngwọta na 1180 Celsius C maka 1 hour.Prior na-ekpuchi elu nke 1 hour. cm2 na-egbu maramara na 2000 grit na silicon carbide paper na n'ihu polished na 0.05 μm Al2O3 ntụ ntụ suspension. A na-echebe akụkụ na ala site na inert paint. Mgbe ihichachara, a na-asacha ihe ndị ahụ na mmiri na-adịghị mma na mmiri na-ekpo ọkụ na 75% (v / 00) .5.5. ìhè maka 0,5 awa tupu eji.
A zụrụ mmiri Pseudomonas aeruginosa MCCC 1A00099 strain si 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, 0.01 NHB, H0.01, 0.08 SrBr2, 0.01H. 3, 0016 NH3, 0016 NaH2PO4, 5.0 peptone, 1.0 yist wepụ na 0.1 ferric citrate.Autoclave na 121°C maka 20 nkeji tupu inoculation.Gụọ sessile na planktonic cell na-eji a hemocytometer n'okpuru a ìhè microscope nke 4.0. inoculation bụ ihe dịka 106 sel / ml.
Electrochemical ule e rụrụ na a kpochapụwo atọ-electrode iko cell na a ọkara olu nke 500 ml. A platinum mpempe akwụkwọ na a jujuru calomel electrode (SCE) e jikọọ na chernobyl via Luggin capillaries jupụtara nnu àkwà mmiri, na-eje ozi dị ka counter na akwụkwọ electrodes, karị. Iji mee ka ndị na-arụ ọrụ electrodes, a roba-ntekwasa na-ekpuchi na onye ọ bụla n'ime ọla kọpa ekpuchi-epocimen nke ọ bụla cm ekpuchi-epocimen na-ekpuchi 1 cm 1. d n'elu ebe maka electrode na-arụ ọrụ. N'oge electrochemical nha, samples e debere na 2216E ọkara na nọgidere na-enwe na a mgbe nile incubation okpomọkụ (37 Celsius C) na a mmiri bath.OCP, LPR, EIS na ike dynamic polarization data e tụrụ site na iji ihe Autolab potentiostat (Reference 600TM, Gamry Instruments, Inc.5) . nso nso nke -5 na 5 mV na Eocp na a sample ugboro nke 1 Hz.EIS rụrụ na a sine ife na ugboro nso 0.01 ka 10,000 Hz na-eji a 5 mV etinye voltaji na otu ebe Eocp.Tupu nwere ike ihichapụ, na electrodes nọ na-emeghe-circuit mode mgbe ahụ, a na-enweta corization n'efu. 5 V vs. Eocp na nyocha nyocha nke 0.166 mV / s. A na-emegharị ule ọ bụla ugboro atọ na na-enweghị P. aeruginosa.
A na-eji mpempe akwụkwọ 2000 grit wet SiC na-ehicha ihe atụ maka nyocha nke metallographic wee mee ka ọ dịkwuo mma na 0.05 μm Al2O3 ntụ ntụ maka nlele anya.
Mgbe incubation gasịrị, a na-asacha ihe nlele 3 ugboro 3 na ngwọta phosphate-buffered saline (PBS) (pH 7.4 ± 0.2) wee dozie ya na 2.5% (v / v) glutaraldehyde maka awa 10 iji dozie biofilms. E mesịa dehydrated ya na usoro graded (50%, 0% 0,0% 0,9% 90,05,90,05,095,50% na 2.5% glutaraldehyde. % v / v) nke ethanol tupu ikpochapu ikuku. N'ikpeazụ, a na-efesa elu nke ihe nlele ahụ na ihe nkiri ọla edo iji nye conductivity maka nlele SEM. Ihe oyiyi SEM na-elekwasị anya na ntụpọ ndị nwere mkpụrụ ndụ P. aeruginosa kacha sessile n'elu nke ọ bụla. Mee nyocha EDS iji chọta ihe ndị na-emepụta ihe. A Zeisscanning Germany (Microscope), Zeisscanning Germany (Microscope) na-eji microscope. iji tụọ omimi nke olulu ahụ. Iji hụ olulu ndị na-emebi emebi n'okpuru biofilm, a na-ebu ụzọ kpochapụ ihe nlele ahụ dị ka Chinese National Standard (CNS) GB / T4334.4-2000 iji wepụ ngwaahịa corrosion na biofilm n'elu mpempe ule.
X-ray photoelectron spectroscopy (XPS, ESCALAB250 surface analysis system, Thermo VG, USA) analysis mere site na iji a monochromatic X-ray iyi (aluminom Kα akara na 1500 eV ume na 150 W ike) n'elu a wide adịgide adịgide ike nso 0 n'okpuru ọkọlọtọ ọnọdụ -1350 eV. High-mkpebi e dere spectra eV.
A na-ewepụ ihe ndị a na-emepụta ma kpochaa ya nke ọma na PBS (pH 7.4 ± 0.2) maka 15 s45. Iji hụ na nje bacteria nke biofilms dị na ihe atụ, a na-eji ihe ndị na-emepụta ihe na-emepụta ihe na-eji LIVE / DEAD BacLight Bacterial Viability Kit (Invitrogen, Euescent abụọ, USA, S Fluescent). -9 dye na red fluorescent propidium iodide (PI) dye.N'okpuru CLSM, ntụpọ na fluorescent green na red na-anọchi anya mkpụrụ ndụ ndụ na ndị nwụrụ anwụ. nm maka mkpụrụ ndụ ndụ na 559 nm maka mkpụrụ ndụ nwụrụ anwụ) na-eji igwe Nikon CLSM (C2 Plus, Nikon, Japan) .A tụrụ ọkpụrụkpụ nke biofilm na ọnọdụ nyocha 3-D.
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