Sulfate-dependant microbially induced corrosion of mild steel in the deep sea: a 10-year microbiome study

Background Metal corrosion in seawater has been extensively studied in surface and shallow waters. However, infrastructure is increasingly being installed in deep-sea environments, where extremes of temperature, salinity, and high hydrostatic pressure increase the costs and logistical challenges associated with monitoring corrosion. Moreover, there is currently only a rudimentary understanding of the role of microbially induced corrosion, which has rarely been studied in the deep-sea. We report here an integrative study of the biofilms growing on the surface of corroding mooring chain links that had been deployed for 10 years at ~2 km depth and developed a model of microbially induced corrosion based on flux-balance analysis. Methods We used optical emission spectrometry to analyze the chemical composition of the mooring chain and energy-dispersive X-ray spectrometry coupled with scanning electron microscopy to identify corrosion products and ultrastructural features. The taxonomic structure of the microbiome was determined using shotgun metagenomics and was confirmed by 16S amplicon analysis and quantitative PCR of the dsrB gene. The functional capacity was further analyzed by generating binned, genomic assemblies and performing flux-balance analysis on the metabolism of the dominant taxa. Results The surface of the chain links showed intensive and localized corrosion with structural features typical of microbially induced corrosion. The microbiome on the links differed considerably from that of the surrounding sediment, suggesting selection for specific metal-corroding biofilms dominated by sulfur-cycling bacteria. The core metabolism of the microbiome was reconstructed to generate a mechanistic model that combines biotic and abiotic corrosion. Based on this metabolic model, we propose that sulfate reduction and sulfur disproportionation might play key roles in deep-sea corrosion. Conclusions The corrosion rate observed was higher than what could be expected from abiotic corrosion mechanisms under these environmental conditions. High corrosion rate and the form of corrosion (deep pitting) suggest that the corrosion of the chain links was driven by both abiotic and biotic processes. We posit that the corrosion is driven by deep-sea sulfur-cycling microorganisms which may gain energy by accelerating the reaction between metallic iron and elemental sulfur. The results of this field study provide important new insights on the ecophysiology of the corrosion process in the deep sea.

Artificial Intelligence as an Emerging Technology in Global Trade

With Industry 4.0 and now 5.0 technologies, the entire globe is embracing these changes. Artificial intelligence-powered systems have immense potential to eliminate international geographical barriers and prove to influence global trade worldwide. The present study highlights how AI increases productivity, economic development, and provides international trade with new horizons. The global value chains, prediction of future trends like changes in consumer demand, risk management, supply chain links are some of the key applications of AI in the sector. AI empowers international trade negotiations to analyze economic trajectories of negotiating partners, adjustments of trade barriers at different rates and scenarios. The chapter will cover the support of AI to access global trade data, its response to diverse challenges, international expansions through digital platforms, support in translations, mechanism of demand prediction, automation of administration with increased efficiency and utility, smart manufacturing, barriers, and influences.

Credit Shock Propagation Along Supply Chains: Evidence from the CDS Market

Using a panel of credit default swap (CDS) spreads and supply chain links, we observe that both favorable and unfavorable credit shocks propagate through supply chains in the CDS market. Particularly, the three-day cumulative abnormal CDS spread change (CASC) is 63 basis points for firms whose customers experienced a CDS up-jump event (an adverse credit shock). The value is 74 basis points if their suppliers experienced a CDS up-jump event. The corresponding three-day CASC values are –36 and –38 basis points, respectively, for firms whose customers and suppliers, respectively, experienced an extreme CDS down-jump event (a favorable credit shock). These effects are approximately twice as large for adverse credit shocks originating from natural disasters. Credit shock propagation is absent in inactive supply chains and is amplified if supply chain partners are followed by the same analysts. Industry competition and financial linkages between supply chain partners, such as trade credit and large sales exposure, amplify the shock propagation along supply chains. Strong shock propagation persists through second and third supply chain tiers for adverse shocks but attenuates for favorable shocks. This paper was accepted by Kay Giesecke, finance.

Classification of Objects of Supply Chain Management to Ensure Their Sustainability

Classifications of objects of supply chain management create the basis for managing their sustainability. The author proposes a hierarchy of priorities regarding managed objects − systems, processes and relations, which implies creation of adequate anticrisis measures for operational management of resource flows.The objectives of the study are to clarify and supplement classifications of supply chain management objects based on their qualitative characteristics. The tasks of the study are to identify the problems of classification of objects of supply chain management, to determine the prerequisites and to determine ways to solve these problems.The methodological basis of the research is formed by the provisions of logistics as a science of resource flow management and supply chain management as a science of managing systems and processes of creating value for end users of products and/or services.Logical-structural methods and tools of binary matrices have allowed to develop classifications of flows of the first (A) and second (B) levels, creating basis for adoption of codes of those flows indicating types of systems and processes and ensuring thus their sustainability. The proposed hierarchy of prioritisation of managed objects reveals the dependences that govern the anti-crisis measures of operation management of resource flows. The research results make it possible to eliminate the contradictions between the goals of the supply chain links (suppliers) and requirement chains (consumers) and, on this basis, to organise their effective interaction.

Sulfate-dependant microbially induced corrosion of mild steel in the deep-sea: a 10-year microbiome study

Background Metal corrosion in seawater has been extensively studied in surface and shallow waters. However, infrastructure is increasingly being installed in deep-sea environments, where extremes of temperature, salinity and high hydrostatic pressure increase the costs and logistical challenges associated with monitoring corrosion. Moreover, there is currently only a rudimentary understanding of the role of microbially induced corrosion, which has rarely been studied in the deep-sea. We report here an integrative study of the biofilms growing on the surface of corroding mooring chain links that had been deployed for 10 years at ~2 km depth and developed a model of microbially induced corrosion based on flux-balance analysis. Methods We used optical emission spectrometry to analyse the chemical composition of the mooring chain and energy-dispersive X-ray spectrometry coupled with scanning electron microscopy to identify corrosion products and ultrastructural features. The taxonomic structure of the microbiome was determined using shotgun metagenomics and was confirmed by 16S amplicon analysis and quantitative PCR of the dsrB gene. The functional capacity was further analysed by generating binned, genomic assemblies and performing flux-balance analysis on the metabolism of the dominant taxa. Results The surface of the chain links showed intensive and localised corrosion with structural features typical of microbially induced corrosion. The microbiome on the links differed considerably from that of the surrounding sediment, suggesting selection for specific metal-corroding biofilms dominated by sulfur-cycling bacteria. The core metabolism of the microbiome was reconstructed to generate a mechanistic model that combines biotic and abiotic corrosion. Based on this metabolic model, we propose that sulfate reduction and sulfur disproportionation might play key roles in deep-sea corrosion. Conclusions The corrosion rate observed was higher than what could be expected from abiotic corrosion mechanisms under these environmental conditions. High corrosion rate and the form of corrosion (deep pitting) suggest that the corrosion of the chain links was driven by both abiotic and biotic processes. We posit that the corrosion is driven by deep-sea sulfur-cycling microorganisms which may gain energy by accelerating the reaction between metallic iron and elemental sulfur. The results of this field study provide important new insights on the ecophysiology of the corrosion process in the deep sea.

Electro-Optical Probing for Capturing Fast-to-Rise Scan Chain Failures

The paper discusses an imaging sensor exhibiting a fast-to-rise sanity check failure from a scan chain test. The DUT was prepared for backside analysis in a portable daughter-card [1] that enabled the analyst to easily shift between testing platforms such as a standard imaging tester bench and compact scan diagnosis system [2], while being inspected under the Electro-Optical Probing (EOP) machine. To find a failing flip-flop in several-thousands long chain, broken scan chain analysis was performed to narrow down the search to a few chain links was implemented. EOP methods of fault isolation were employed to verify the location of the broken scan cell in those selected flip-flops. Finally, parallel lapping was done to confirm the location of the failing flip-flop under a SEM.

Research on the Problems and Countermeasures of Enterprise Financial Management under the Current Internet Economy

The application of Internet technology in the development of enterprises can effectively reflect the business situation of enterprises. Through the Internet platform, enterprises can display their own advantages and specialties, realize the supply chain links all over the world, strengthen the development trend of business digitization, use the digital mode to enable their own management mode, give full play to the advantages of e-commerce, and put forward higher requirements for the internal financial management of enterprises.Therefore, we should make full use of the Internet and understand the Internet with the help of the Internet, To improve the efficiency of financial management.