PPy–TiO2–phenylalanine composites as anticorrosive coatings electrodeposited over Fe–C steel surface in the marine environment

2020 ◽  
Vol 34 (17) ◽  
pp. 1823-1839
Author(s):  
Priti Pahuja ◽  
Rinki Malik ◽  
Nisha Saini ◽  
Sumit Kumar ◽  
Suman Lata
Keyword(s):  
Marine Environment ◽  
Steel Surface ◽  
Anticorrosive Coatings

EELS characterization of “Smut” layer films on steel surface prepared for chrome plating by anodic etching

1995 ◽  
Vol 53 ◽  
pp. 538-539
Author(s):  
E Y. Wang ◽  
J. T. Cherian ◽  
A. Madsen ◽  
R. M. Fisher
Keyword(s):  
Steel Surface ◽  
Surface Preparation ◽  
Treatment Method ◽  
Chrome Plating ◽  
Transmission Electron ◽  
Alloy Steels ◽  
Pre Treatment ◽  
Hard Chrome ◽  
Electron Energy Loss

Many steel parts are electro-plated with chromium to protect them against corrosion and to improve their wear-resistance. Good adhesion of the chrome plate to the steel surface, which is essential for long term durability of the part, is extremely dependent on surface preparation prior to plating. Recently, McDonnell Douglas developed a new pre-treatment method for chrome plating in which the steel is anodically etched in a sulfuric acid and hydrofluoric acid solution. On carbon steel surfaces, this anodic pre-treatment produces a dark, loosely adhering material that is commonly called the “smut” layer. On stainless steels and nickel alloys, the surface is only darkened by the anodic pre-treatment and little residue is produced. Anodic pre-treatment prior to hard chrome plating results in much better adherence to both carbon and alloy steels.We have characterized the anodic pre-treated steel surface and the resulting “smut” layer using various techniques including electron spectroscopy for chemical analysis (ESCA) on bulk samples and transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) on stripped films.

Spatial assemblage structure of shallow-water reef fish in Southwest Australia

2020 ◽  
Vol 649 ◽  
pp. 125-140
Author(s):  
DS Goldsworthy ◽  
BJ Saunders ◽  
JRC Parker ◽  
ES Harvey
Keyword(s):  
Shallow Water ◽  
Reef Fish ◽  
Marine Environment ◽  
Fish Assemblages ◽  
Canopy Cover ◽  
Reef Fishes ◽  
Reef Fish Assemblage ◽  
Reef Type ◽  
Present Distribution ◽  
Southwest Australia

Bioregional categorisation of the Australian marine environment is essential to conserve and manage entire ecosystems, including the biota and associated habitats. It is important that these regions are optimally positioned to effectively plan for the protection of distinct assemblages. Recent climatic variation and changes to the marine environment in Southwest Australia (SWA) have resulted in shifts in species ranges and changes to the composition of marine assemblages. The goal of this study was to determine if the current bioregionalisation of SWA accurately represents the present distribution of shallow-water reef fishes across 2000 km of its subtropical and temperate coastline. Data was collected in 2015 using diver-operated underwater stereo-video surveys from 7 regions between Port Gregory (north of Geraldton) to the east of Esperance. This study indicated that (1) the shallow-water reef fish of SWA formed 4 distinct assemblages along the coast: one Midwestern, one Central and 2 Southern Assemblages; (2) differences between these fish assemblages were primarily driven by sea surface temperature, Ecklonia radiata cover, non-E. radiata (canopy) cover, understorey algae cover, reef type and reef height; and (3) each of the 4 assemblages were characterised by a high number of short-range Australian and Western Australian endemic species. The findings from this study suggest that 4, rather than the existing 3 bioregions would more effectively capture the shallow-water reef fish assemblage patterns, with boundaries having shifted southwards likely associated with ocean warming.

PERAN DESIGNATED PERSON ASHORE (DPA) DALAM PENGOPERASIAN KAPAL YANG AMAN SESUAI KETENTUAN NASIONAL DAN INTERNASIONAL

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Suganjar Suganjar ◽  
Renny Hermawati
Keyword(s):  
Marine Environment ◽  
Emergency Preparedness ◽  
Safety Management ◽  
Shipping Industry ◽  
Safe Operation ◽  
International Regulation ◽  
Loss Of Life ◽  
Shipping Company ◽  
Environmental Protection Policy ◽  
Human Injury

<p><em>Safety management in the shipping industry is based on an international regulation. It is International Safety Management Code (ISM-Code) which is a translation of SOLAS ‘74 Chapter IX. It stated that t</em><em>he objectives of the Code are to ensure safety at sea, prevention of human injury or loss of life, and avoidance of damage to the environment, in particular, to the marine environment, and to property.it is also</em><em> requires commitment from top management to implementation on both company and on board. The implementation of the ISM-Code is expected to make the ship’s safety is more secure. The ISM-Code fulfillment refers to 16 elements, there are; General; Safety and Environmental Protection Policy; Company Responsibility and Authority; Designated Person(s); Master Responsibility and Authority; Resources and Personnel; Shipboard Operation; Emergency Preparedness; Report and Analysis of Non-conformities, Accidents and Hazardous Occurrences; Maintenance of the Ship and Equipment; Documentation; Company Verification, Review, and Evaluation;  Certification and Periodical Verification; Interim Certification; Verification; Forms of Certificate. The responsibility and authority of Designated Person Ashore / DPA in a shipping company is regulated in the ISM-Code. So, it is expected that DPA can carry out its role well, than can minimize the level of accidents in each vessels owned/operated by each shipping company.</em></p><p><em></em><strong><em>Keywords :</em></strong><em> ISM Code,</em><em> </em><em>Safety management, </em><em>Designated Person Ashore</em></p><p> </p><p> </p><p>Manajemen keselamatan di bidang pelayaran saat ini diimplementasikan dalam suatu peraturan internasional yaitu <em>International Safety Management Code</em> (<em>ISM-Code</em>) yang merupakan penjabaran dari <em>SOLAS 74 Chapter IX</em>-<em>Management for the safe operation of ships</em>. Tujuan dari <em>ISM-Code</em> <em>“The objectives of the Code are to ensure safety at sea, prevention of human injury or loss of life, and avoidance of damage to the environment, in particular, to the marine environment, and to property”</em> dan  <em>ISM-Code</em> menghendaki adanya komitmen dari manajemen tingkat puncak sampai pelaksanaan, baik di darat maupun di kapal.  Pemberlakuan <em>ISM-Code</em> tersebut diharapkan akan membuat keselamatan kapal menjadi lebih terjamin. Pemenuhan <em>ISM-Code</em> mengacu kepada 16 elemen yang terdiri dari ; umum; kebijakan keselamatan  dan perlindungan lingkungan; tanggung jawab dan wewenang perusahaan; petugas yang ditunjuk didarat; tanggung jawab dan wewenang nahkoda; sumber daya dan personil; pengopersian kapal; kesiapan menghadapi keadaan darurat; pelaporan dan analisis ketidaksesuaian, kecelakaan dan kejadian berbahaya; pemeliharaan kapal dan perlengkapan;  Dokumentasi; verifikasi, tinjauan ulang, dan evaluasi oleh perusahaan; sertifikasi dan verifikasi berkala; sertifikasi sementara; verifikasi; bentuk sertifikat. Tugas dan tanggungjawab <em>Designated Person Ashore/DPA </em>didalam suatu perusahaan pelayaran<em>, </em>telah diatur di dalam <em>ISM-Code.</em>  Sehingga diharapkan agar DPA dapat melaksanakan peranannya dengan baik, sehingga dapat menekan tingkat kecelakaan di setiap armada kapal yang dimiliki oleh setiap perusahaan pelayaran.</p><p class="Style1"><strong>Kata kunci</strong> : <em>ISM Code</em>, Manajemen keselamatan, <em>Designated Person Ashore</em></p>

Specificity of Lectins Labeled with Colloidal Gold to the Exopolymeric Matrix Carbohydrates of the Sulfate-Reducing Bacteria Biofilm Formed on Steel

2020 ◽  
Vol 82 (5) ◽  
pp. 11-20
Author(s):  
D.R. Abdulina ◽  
◽  
L.M. Purish ◽  
G.O. Iutynska ◽  
◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Colloidal Gold ◽  
Steel Surface ◽  
Lectin Binding ◽  
Sulfate Reducing Bacteria ◽  
Gold Particles ◽  
Sulfate Reducing ◽  
Transmission Electron ◽  
Reducing Bacteria

The studies of the carbohydrate composition of the sulfate-reducing bacteria (SRB) biofilms formed on the steel surface, which are a factor of microbial corrosion, are significant. Since exopolymers synthesized by bacteria could activate corrosive processes. The aim of the study was to investigate the specificity of commercial lectins, labeled with colloidal gold to carbohydrates in the biofilm exopolymeric matrix produced by the corrosive-relevant SRB strains from man-caused ecotopes. Methods. Microbiological methods (obtaining of the SRB biofilms during cultivation in liquid Postgate B media under microaerophilic conditions), biochemical methods (lectin-binding analysis of 10 commercial lectins, labeled with colloidal gold), transmission electron microscopy using JEM-1400 JEOL. Results. It was shown using transmission electron microscopy that the binding of lectins with carbohydrates in the biofilm of the studied SRB strains occurred directly in the exopolymerіс matrix, as well as on the surfaces of bacterial cells, as seen by the presence of colloidal gold particles. For detection of the neutral carbohydrates (D-glucose and D-mannose) in the biofilm of almost all studied bacterial strains PSA lectin was the most specific. This lectin binding in biofilms of Desulfotomaculum sp. К1/3 and Desulfovibrio sp. 10 strains was higher in 90.8% and 94.4%, respectively, then for ConA lectin. The presence of fucose in the SRB biofilms was detected using LABA lectin, that showed specificity to the biofilm EPS of all the studied strains. LBA lectin was the most specific to N-аcetyl-D-galactosamine for determination of amino sugars in the biofilm. The amount of this lectin binding in D. vulgaris DSM644 biofilm was 30.3, 10.1 and 9.3 times higher than SBA, SNA and PNA lectins, respectively. STA, LVA and WGA lectins were used to detect the N-acetyl-Dglucosamine and sialic acid in the biofilm. WGA lectin showed specificity to N-acetyl-D-glucosamine in the biofilm of all the studied SRB; maximum number of bounded colloidal gold particles (175 particles/μm2) was found in the Desulfotomaculum sp. TC3 biofilm. STA lectin was interacted most actively with N-acetyl-D-glucosamine in Desulfotomaculum sp. TC3 and Desulfomicrobium sp. TC4 biofilms. The number of bounded colloidal gold particles was in 9.2 and 7.4 times higher, respectively, than using LVA lectin. The lowest binding of colloidal gold particles was observed for LVA lectin. Conclusions. It was identified the individual specificity of the 10 commercial lectins to the carbohydrates of biofilm matrix on the steel surface, produced by SRB. It was estimated that lectins with identical carbohydrates specificity had variation in binding to the biofilm carbohydrates of different SRB strains. Establishing of the lectin range selected for each culture lead to the reduction of the scope of studies and labor time in the researching of the peculiarities of exopolymeric matrix composition of biofilms formed by corrosiverelevant SRB.

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