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Anodic aluminium oxide-copper (AAO-Cu) coatings were prepared on the aluminium (Al) alloy substrates to attain excellent antibacterial performance and mechanical stability. The nanoporous AAO interlayer was ob-tained by anodic oxidation with an outer Cu layer deposited by electroplating. The intermediate zone (similar to 2 mu m thick) of the AAO-Cu coating plays a significant role in the coating properties. The interlocking effect in the AAO-Cu intermediate zone significantly enhances the coating adhesion and curbs the coating defoliation. The anti-bacterial tests show that the AAO-Cu zone provides excellent antibacterial ability even when the outer Cu coating was removed. The sustained antibacterial rate of the AAO-Cu intermediate zone against E. coli exceeded 95%. The Cu ions released from the embedded Cu in the nanoporous AAO structure ensure a long-term antibacterial capability. This coating system can be promoted in a large wide range of antibacterial products in public.
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Contact infection of bacteria and viruses has been a critical threat to human health. The worldwide outbreak of COVID-19 put forward urgent requirements for the research and development of the self-antibacterial materials, especially the antibacterial alloys. Based on the concept of high-entropy alloys, the present work designed and prepared a novel Co0.4FeCr0.9Cu0.3 antibacterial high-entropy alloy with superior antibacterial properties without intricate or rigorous annealing processes, which outperform the antibacterial stainless steels. The antibacterial tests presented a 99.97% antibacterial rate against Escherichia coli and a 99.96% antibacterial rate against Staphylococcus aureus after 24 h. In contrast, the classic antibacterial copper-bearing stainless steel only performed the 71.50% and 80.84% antibacterial rate, respectively. The results of the reactive oxygen species analysis indicated that the copper ion release and the immediate contact with copper-rich phase had a synergistic effect in enhancing antibacterial properties. Moreover, this alloy exhibited excellent corrosion resistance when compared with the classic antibacterial stainless steels, and the compression test indicated the yield strength of the alloy was 1015 MPa. These findings generate fresh insights into guiding the designs of structure-function-integrated antibacterial alloys.
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This article presents the history of zinc, its production and demand. The quantity of zinc production, both primary zinc from ores and concentrates, and secondary zinc from scrap and zinc-rich waste, was discussed. A comprehensive economic analysis covers zinc prices in the years 1960–2021. The basic methods of obtaining zinc from ores, including pyrometallurgical (Imperial Smelting Process ISP, Kivcet, Ausmelt) and hydrometallurgical (roasting–leaching–electrowinning RLE, atmospheric direct leaching ADL, Engitec Zinc Extraction EZINEX, zinc pressure leach) and their short characteristics, are presented. The global zinc market and the main areas of its application were analyzed. Technologies used for the recovery of zinc from scrap are discussed along with their characteristics. Galvanized steel is the main source of secondary zinc, both in the galvanizing process and in the remelting of galvanized steel. It can be easily recycled with other scrap steel in the electric arc furnace (EAF) for steel production. Currently, with high volatility in the price of zinc, as well as its natural resources in the earth's crust, recycling is an important activity, despite the fact that zinc concentrates have a relatively constant chemical composition, while the resulting zinc waste contains zinc in varying amounts.
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40% of the world gas reserves are located in in the Middle East, of which most contain high amounts of corrosive gases H2S and CO2, this with other environmental factors exerts stress on metallic and nonmetallic materials. For Baker Hughes to address these challenges, one answer was to establish local competencies in the Kingdom of Saudi Arabia as a H2S lab and materials science focused team, ultimately targeting the reduction of total expense of corrosion, and to tap into the research capabilities and expertise available in the ecosystem. H2S gas is a major health and safety challenge to deal with, as it is a lethal, flammable, corrosive. The analysis to design the lab was supported by methods of Asset Integrity Risk Management looking on barriers, process, and industry standards. The human factor was considered to ensure competency, mindset & culture. Among others, OSHA standards were followed to develop the Chemical Hygiene Plan (CHP) and respiratory protection program and Emergency Response and Operations Plan (EROP). An unexpected challenge arose during the COVID-19 pandemic where measures were taken to limit infection while maintaining lab operation. The lab started operation with a narrow scope to focus on critical lab operational skill development, successive new competencies and workflows are added following a Management of Change (MOC) process. Current developments leverage the labs growing competence to address arising challenges on ultra-high H2S, CO2 for CCUS, and hydrogen for the energy transaction. Copyright © 2022, International Petroleum Technology Conference.
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Wound closing is one of the widely performed and prominent clinical practices in the surgical intervention process. A physician or surgeon has several options ranging from surgical sutures and adhesive strips to fibrin glue for effective wound closure to close the commonly occurring surgical cuts and deep skin tissue injuries. However, all the commercially available wound closure devices have some limitations in each and another perspective. From the beginning of the late 90s, surgical staples got tremendous attention as efficient wound closure devices for their time-effective and sufficient mechanical strength, performance feasibility, fewer chances of surgical site infection and require minimal expertise characteristics in consideration of remote location. Even in the context of the recent COVID19 pandemic, the clinical acceptance and patient compliance for the staples have increased due to minimizing the chances of prolonged interaction between the patient and physicians. The surgical staples application is extensive and diversified, ranging from common external cuts to highly complex surgery procedures like laparoscopic appendectomy, intestinal anastomosis, etc. Thus, in this literature review, we try to give a comprehensive glimpse of the development and current state-of-the-art surgical staples in consideration with research from a commercial point of view. On a special note, this review also describes a very brief outline of the regulatory aspects and some common internationally acceptable 'de jure standards for the development of commercially viable surgical staples. Copyright © 2022 The Author(s)
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Due to increasing pollution that can be attributed primarily to fossil fuel consumption the world has been facing unprecedented challenges. This has caused global warming and aggravated the current pandemic (COVID-19) problem, as well. Owing to the increasing demand for fossil fuels and excessive consumption of petroleum-based resources, it has become vital to adopt alternative renewable sources. In recent times, biomass waste is being used efficiently as an ideal green corrosion inhibitor because of its availability, ecological acceptability, biodegradability, renewability, phytoconstituent-rich nature, and, most significantly, nontoxic nature. Their valorizations expand potential application in the industry rather than "waste to energy" in the circular economy perception. There is a strong interest globally in developing suitable technology that can use biomass wastes for different applications, including corrosion inhibitors. In this regard, this chapter presents a collection of articles designed to inform metallurgists, designers, and engineers of the nature of corrosion and means of its prevention. Beginning with the analysis of fundamental scientific principles involved in corrosion science, it covers the basics as well as other topics such as causes of corrosion, methods of mitigating corrosion, the use and characteristics of inhibitors, classes of corrosion inhibitors, factors to consider in selecting corrosion inhibitor, and classification of corrosion inhibitors. Attention is given to biomass waste inhibitors through literature review and the biomass wastes extract used as corrosion inhibitors and their acting mechanisms are presented. Sections include an introduction, corrosion inhibitors, and biomass waste extract as corrosion inhibitors. © 2022 Walter de Gruyter GmbH, Berlin/Boston. All rights reserved.
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Oil and Gas industry is seeking new ways to improve efficiencies, reducing operating costs and increasing revenues in the current volatile market conditions. Data Science and all the new emerging technologies enable the discovery of new opportunities and digitalization is a vital element for making business more effective and efficient. While COVID19 has disrupted the world, ADNOC Onshore has recognized the importance of reskilling and empowering the future workforce through strategic enterprise data science and analytics program to achieve 2030 smart growth strategy. This paper talks about successful approach and enablers for development of in-house capability for transformation that lead to generating significant business value The digital transition can pose both challenges and opportunities in this transformation. ADNOC ONSHORE has developed an integrated framework to encourage and accelerate data science capabilities. This framework promotes a vision with collaborative, sustainable mechanisms to develop talent. It is not just the formal learning and additional professional qualification that make it possible to build this in house capability. There are five major areas are enabled this framework such as data science & analytics skills competency model, sustainable on-line collaborative learning program, organizational culture change, democratizing AI through open platform & a digital business model for performing real business problems/use case PoCs. Each area has a detailed program and execution strategy with a collaborative effort from technical and non-technical stakeholders. ADNOC ONSHORE has successfully implemented this framework and able to certify 20 employees as part of this program. The Data Science Competency Model identified and defined the skills required to be successful within the enterprise with a clear learning path and mentorship. The leadership played a pivotal role to encourage data driven decision making and predictive capabilities in addition to executive awareness to lead the change with clear performance indicators. By democratizing AI platform across upstream user community, six real business cases have been successfully developed with clear business value in subsurface and production workflows according to the defined digital business model. The successful business cases have improved efficiency by 75% in performing cement & corrosion log interpretation & well portfolio optimization. Data driven analytics have been evaluated in subsurface workflows such as infill location optimization, gas-lift candidate identification and they have complemented the existing techniques. The framework has been successfully extended to other group companies in ADNOC. The rapid growth of AI in business in the last five years presents an opportunity for oil and gas professionals for enhancing the skills and transformation. This paper talks about an integrated framework, learning path, democratizing AI, engagement of leadership, digital business model for business case evaluation by applying agile way of working and sustainable value creation. Copyright © 2022, Society of Petroleum Engineers.
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In this work, we report synthesis, characterization and computational studies of the symmetric thiophene-based compound thiophene-2,5-diylbis((3-mesityl-3-methylcyclobutyl)methanone) (1) obtained from 2,2'-thiobis(1-(3-mesityl-3-methylcyclobutyl)ethan-1-one) and glyoxal using the Hinsberg thiophene ring synthesis approach. The Density Functional Theory (DFT) calculations were performed to probe the structure of 1, as well as its electronic and optical properties. The global reactivity descriptors, as well as molecular electrostatic potential (MEP), were revealed to probe the reactivity and to determine the reactive centers of 1. The DFT calculations were also applied to probe 1 as a potential corrosion inhibitor for some important metals used in implants. Electron charge transfer from the molecule of 1 to the surface of Ni, Au, Co, Cu, Mo, W, Fe and Cr was revealed. Bioavailability, druggability as well as absorption, distribution, metabolism, excretion and toxicity properties of 1 were predicted. Molecular docking was applied to examine the influence of this compound on a series of the SARS-CoV-2 proteins. Compound 1 exhibited the best binding affinity with the Nsp14 (N7-MTase), Papain-like protease (PLpro) and Nsp16 (MGP site) proteins as well as demonstrated a similar efficiency toward both the native and mutated Spike proteins, RDB. [ FROM AUTHOR] Copyright of Polycyclic Aromatic Compounds is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)
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Li–air batteries have received significant attention for their ultrahigh theoretical energy density. However, the byproducts induced by attacking air hinder the conversion of Li–O2 batteries to Li–air batteries. Humidity is one of the main obstacles, not only causing side reactions with the discharge products but also leading to rapid corrosion of the lithium anode. Here, we fabricated a novel composite hydrophobic catalyst by loading RuO2 and graphene on N-doped porous carbon. The catalyst was endowed with hydrophobicity and showed superior catalytic performance and low affinity to water in the air. A Li–air battery equipped with this novel composite catalyst exhibited eminent cycling performance in pure oxygen (over 470 h), humid oxygen [∼40% relative humidity (RH), over 310 h], and ambient air (∼42% RH, over 330 h) at a current density of 500 mA g−1, and the discharge specific capacity increased from 13122.1 to 19358.6 mAh g−1. © 2022
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Over the past couple of decades, newer formulations on the market have trended toward less dependence on nonrenewable resources like petroleum products and fewer ingredients like biocides that pose worker health concerns. Oil-free formulations check these boxes, and they also help with reducing foam, increasing fluid life and eliminating the need to clean oil films from the finished workpieces. However, they don't work for all applications, they can be expensive and they can present waste disposal problems. Here, McGuire talks about oil-free metalworking fluids.
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Two drugs have been authorized by the Algerian health Ministry to be used in Algeria to treat coronavirus disease 2019 (COVID-19) patients, once is Hydroxychloroquine (HCQ) and the other is Chloroquine (CQ). These drugs have been theoretically studied in order to know their active sites, and vibrational and electronic properties using Density Functional Theory (DFT) at the B3LYP/6-31G (d.p) level. The optimized molecular structures, the vibrational spectra, the HOMO and LUMO properties, dipole moments, Molecular Electrostatic Potentials (MEP), and atomic charges are calculated. In addition, the reactivity of drug molecules has been discussed by calculating some descriptors such as energy gap, hardness, local softness, electronegativity, and electrophilicity.
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Reinforced concrete (RC) elements suffer continuous deterioration across their lifetime from in-situ aggressive environmental factors. Spiral reinforcing corrodes preferentially to longitudinal reinforcing, due to the smaller amount of protective cover concrete. Therefore, identifying the true shear resistance of a RC member in its deteriorated state is a critical component that must be addressed when assessing the seismic reliability of a structure. This research addresses the issue of chloride-induced corrosion damage in RC circular bridge piers, specifically focusing on the degradation rate of the seismic shear capacity. Twenty-two columns in total are to be tested in this experimental program. Three distinct damage levels are obtained through artificial corrosion simulation using two variations of the im-pressed-current technique. Effects of spiral spacing, diameter and volumetric ratio are also considered in this experimental work. Two current densities are induced: 200 μA/cm2 and 300 μA/cm2. Due to continual delays with Covid-19 restrictions, no results are yet available to discuss. © 2021, fib. The International Federation for Structural Concrete. All rights reserved.
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The Covid sickness (COVID19) pandemic is quickly expanding across the world. There is no legitimate therapy for this illness except for by supporting our resistance we can battle with this infection so to battle Coronavirus contamination the famous dietary enhancement bovine colostrums having bunches of utilization to battle against viral disease. It go about an immunomodulatory, anti-inflammatory, Antibacterial effect. The most significant part found in colostrum is lactoferrin which is a 80 KDA glycoprotein containing around 703 amino corrosive and having its capacity to tie with iron by restricting with iron, lactoferrin retain iron from the climate and forestalls viral heap of pathogens. The Covid didn't get authoritative therapy because of viral transformation;this review is accommodating for helping the invulnerable framework in coronavirus patient.
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The article considers the features of aircraft maintenance in accordance with the requirements of the corrosion protection and prevention program. Differences in aircraft maintenance procedures under COVID-19 restrictions are presented. Statistical data on the occurrence of corrosion damage under typical operation and during long-Term storage are analyzed. © 2022 The Authors. Published by ELSEVIER B.V.
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The rise of carbon dioxide (CO2) levels in the atmosphere emphasises the need for improving the current carbon capture and storage (CCS) technology. A conventional absorption method that utilises amine-based solvent is known to cause corrosion to process equipment. The solvent is easily degraded and has high energy requirement for regeneration. Amino acids are suitable candidates to replace traditional alkanolamines attributed to their identical amino functional group. In addition, amino acid salt is a green material due to its extremely low toxicity, low volatility, less corrosive, and high efficiency to capture CO2. Previous studies have shown promising results in CO2 capture using amino acids salts solutions and amino acid ionic liquids. Currently, amino acid solvents are also utilised to enhance the adsorption capacity of solid sorbents. This systematic review is the first to summarise the currently available amino acid-based adsorbents for CO2 capture using PRISMA method. Physical and chemical properties of the adsorbents that contribute to effective CO2 capture are thoroughly discussed. A total of four categories of amino acid-based adsorbents are evaluated for their CO2 adsorption capacities. The regeneration studies are briefly discussed and several limitations associated with amino acid-based adsorbents for CO2 capture are presented before the conclusion.
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The oil and gas industry worldwide is experiencing problems of vandalism and mechanical deterioration due to corrosion in its various pipeline transport systems, a drop in the price of hydrocarbons due to the COVID-19, limitation of maintenance processes. This article provides a contribution original to the knowledge and management of a pipeline transportation system (PTS), without an immediate high impact that would help reduce property loss due to corrosion, through the development of intelligent evaluation models that combine field data, laboratory, and cognitive knowledge in a case study in Mexico. The research is divided into Part 1: modeling, a Fuzzy expert system (FES) unified the knowledge of corrosion specialists and mechanical integrity studies (MIS) and identified evolutionary corrosion patterns with reliability of 0.9029. An artificial neural network (ANN) supported by statistics and metallography establishes test reliability of 0.9556 and determines the corrosion inhibition capacity (C) of Mexican hydrocarbon mixtures based on their properties compared to carbon steel. Part 2: analysis of the operational and economic risk of the PTS under corrosive effects, using Monte Carlo simulation (MCS) estimates various financial scenarios considering corrosive profiles of soils, supply, demand, and inflation.
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Aluminium and its alloys are considered as most favorable material in aerospace, automobile and marine industries due to its light weight and high strength to weight ratio. Outer body of the airplanes, ships, automobile etc. are usually made of aluminium and its alloys. The tensile and fatigue failure of a component is highly affected by the corrosion behavior of the material in different environments. Surface roughness of the specimens plays an important role in determining the corrosion behavior of material. In the situations like Covid-19 or while waiting for repairing, airplanes, cars, ships etc. stand idle for months in the rainy environments. As rain is acidic in nature, metal starts corroding when get in contact with it. In the present work, corrosion due to acid rain on the polished surface of as-cast Al6061 alloy is analyzed through simulated acid rain environment (pH = 4). The effect of surface roughness on the corrosion rate was also investigated. It was observed that corrosion rate decreases as the surface finish of the specimen increases.
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[...]it is clear by the policies and scenarios which are already laid out, that we need to investigate in detail and improve the existing technologies in an effective manner. [13] present a frequency splitting based energy management strategy in a microgrid consisting of a diesel generator, supercapacitors, wind turbine, solar photovoltaic generator, and lithium batteries. A dedicated building has been recommended for the electrode station for the sake of limiting energy consumption, preventing electrochemical corrosion, protecting from environmental constraints, and reducing the risk of fire hazards by increasing the fire resistance by installing a firefighting system. [...]a design process for the electrode station building has been proposed in detail.
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The current work explores the potential for recycling unused or expired Midazolam (MID) drug, a benzodiazepine derivative, as an efficient corrosion inhibitor for copper in nitric acid solution. The technical advantage of recycling expired MID drug relates to the avoidance of organic inhibitor production costs and the reduction of disposal costs of the expired medication. A combination of electrochemical methods (potentiodynamic polarization and electrochemical impedance spectroscopy), weight loss, and quantum chemical calculation were used to assess the inhibition mechanism and efficiency of MID. It was found that inhibition efficiency increases with inhibitor concentration, reaching a highest value of 92.9% for a concentration of 10-4 M MID. MID was classified as a mixed-type inhibitor, showing a preferential cathodic suppression mechanism. The obtained values of -45.89 kJ mol-1 for the standard free energy of adsorption indicate that the inhibition mechanism is based on chemisorption of MID molecules on the copper surface, which obeys the Langmuir isotherm. Surface analysis using scanning electronic microscopy revealed that MID offers high protection against corrosion during both immersion and polarization tests. Molecular modelling and quantum chemical calculations indicated chemical interactions between MID molecules and the copper surface, as well as electrostatic interactions. The results obtained using the different techniques were in good agreement and highlight the effectiveness of MID in the corrosion inhibition of copper.