Biocompatibility Study of CoCrMoSi k Original Alloy Variants

The study follow the improvement of properties of cobalt base alloys, used in medical applications. This scope targeted the obtaining of alloys with friendly biological interactions to human body. If the original variants of CoCrMoSi k (k = 4, 5, 6, 7) alloys don't subjected to the criteria of biological acceptance from animal body, these don't be placed in live body, indifferent the adequacy of the biomaterials properties. Realization of the original alloy variants must consider and the possibility to appear the base pathophysiological phenomena, with determine or not their safety on long time (generate of thrombosis, inflammation, infection and / or inducing and causing neoplasms)

Introduction to Metallic Biomaterials

The paper presents a bibliographic study about the metallic biomaterials, synthesizing the aspects related to properties, applicability, obtaining methods. Biomaterials can be used as medical devices, implants and prostheses. The metallic biomaterials are classified, by chemical composition and structure, in: pure technical metals, metallic alloys and composites with metallic matrix. The material quality of an implant must respect the following criteria: biochemical criteria and biomechanical ones. According to the biochemical criterion, the applicability of a material is determined by its biocompatibility, and from the biochemical criteria, it is determined by the fatigue resistance, the most important parameter, but not the only one

Kinked silicon nanowires-enabled interweaving electrode configuration for lithium-ion batteries

A tri-dimensional interweaving kinked silicon nanowires (k-SiNWs) assembly, with a Ni current collector co-integrated, is evaluated as electrode configuration for lithium ion batteries. The large-scale fabrication of k-SiNWs is based on a procedure for continuous metal assisted chemical etching of Si, supported by a chemical peeling step that enables the reuse of the Si substrate. The kinks are triggered by a simple, repetitive etch-quench sequence in a HF and H2O2-based etchant. We find that the inter-locking frameworks of k-SiNWs and multi-walled carbon nanotubes exhibit beneficial mechanical properties with a foam-like behavior amplified by the kinks and a suitable porosity for a minimal electrode deformation upon Li insertion. In addition, ionic liquid electrolyte systems associated with the integrated Ni current collector repress the detrimental effects related to the Si-Li alloying reaction, enabling high cycling stability with 80% capacity retention (1695 mAh/gSi) after 100 cycles. Areal capacities of 2.42 mAh/cm2 (1276 mAh/gelectrode) can be achieved at the maximum evaluated thickness (corresponding to 1.3 mgSi/cm2). This work emphasizes the versatility of the metal assisted chemical etching for the synthesis of advanced Si nanostructures for high performance lithium ion battery electrodes

The importance of traceability in the beer brewing process within the brewing microproduction workshop

Transparency in identifying the origin of food is a necessity. After a number of recalls and incidents related to food insecurity around the world, consumer awareness of food security issues has increased. In this scenario, food traceability appears as an important tool. The importance of the present paper derives from the approach to a highly current research area, namely the guarantee of food safety, food quality and the continuous concern of alcoholic beverage producers to obtain safe and healthy products. The main objectives and activities consist of: (1) making an exhaustive documentation of the national and international legislation (especially that of the EU) related to the topic addressed; (2) establishing the manufacturing recipe, the raw and auxiliary materials and the optimal technological parameters for beer manufacturing, the development of manufacturing technological norms for the companies in the field (internal quality standards); (3) planning and tracking the production process; (4) physico-chemical characterization of the raw and auxiliary materials that enter the manufacturing process of the analyzed products. This analysis can be useful for the creation and development of new guidelines to improve the production process of beer, aiming at a higher degree of satisfaction of breweries and increasing the degree of safety of foods in the brewery chain

Kinked silicon nanowires: Superstructures by metal assisted chemical etching

We report on metal assisted chemical etching of Si for the synthesis of mechanically-stable, hybrid crystallographic orientation Si superstructures with high aspect ratio, above 200. This one-pot-type method sustains high etching rates and facilitates reproducible results. The protocol enables the control of the number, angle and location of kinks via successive etch-quench sequences. We analysed relevant Au mask catalyst features to systematically assess their impact on a wide spectrum of etched morphologies that can be easily attained and customized by fine tuning of the critical etching parameters. For instance, the designed kinked Si nanowires can be internalized in biological cells, without affecting their viability. An accessible numerical model is provided to explain the etch profiles and the physico-chemical events at the Si-Au-electrolyte interface and offers guidelines for the development of finite-element modeling of metal assisted Si chemical etching

Nanostructured silicon for advanced Li-ion storage systems

The interest in batteries beyond the present intercalation-type chemistry has been clearly catalyzed by the current environmental issues. On the one hand, transport electrification can considerably reduce the well-to-wheel emission through the use of renewable and low carbon electricity stored in efficient batteries. On the other hand, successful exploitation of intermittent energy sources, such as solar or wind, requires energy storage capability, particularly in managing peak electricity production and demand. Several Li-ion battery (LIB) chemistries are well established; however, they can not satisfy the energy demands nor the environmental policies associated with their production and disposal. High-performance, lighter and safer batteries are possible if Si-based electrodes are adopted. Herein, we explored several routes to solve the key failure modes in Si cycling via optimized material and electrode design. First, we present an accessible, room temperature, silicon nanowires (SiNWs) and kinked SiNWs synthesis based on a metal-assisted chemical etching scheme that allows for the reuse of the Si substrate via a sacrificial porous segment. Secondly, we explored an electrode design that is more realistic and suitable for alloying-type electrodes suffering from the volume variations such as Si. In this sense, we report on the mechanical and electrochemical properties of a self-standing Si-carbon-based electrode with optimized porosity to sustain the volume variations during Li-Si alloying reaction. Also, Si surface passivation is discussed as a possible route for extending the cycling life of Si-based electrodes. We particularly study the lithiation fundamentals in Ni coated Si nanostructures and apply our findings towards achieving high-performance Si-based electrodes. We further show that an aqueous conducting polymer, converted mechanochemically to a hydrogel, meets all the requirements as a binder for Si anodes. Not only it enhances the cycling life of Si anodes but also can deflect the current electrode manufacturing process towards a cleaner, safer path. Finally, this work evaluates possible routes to redirect LIB technology towards an environmentally friendlier, safer, and cost-effective direction by developing accessible material synthesis protocols, within low cost and recycling strategies, as well as aqueous processing of battery electrodes.(FSA - Sciences de l'ingénieur) -- UCL, 201

Proceedings of the 2021 IEEE PES Innovative Smart Grid Technologies - Asia (ISGT Asia)

The low-carbon energy transition depends on adopting renewable energy technologies and requires affected industries to adopt best practices for optimized performance, reliable and sustainable operations. Consequently, the legacy energy distribution system faces many challenges in supporting grid stability, reliability, efficiency, and security under this transition setting. Herein, we adopt a quantitative text analysis of 310 articles complemented by a qualitative review to identify how and to what extent the fourth industrial revolution reflects in the energy distribution system. To this end, we map the literature for the technological innovations that support condition-based maintenance of electricity distribution grid under the Industry 4.0 principles. We emphasize how physical asset management enabled by the Industry 4.0 principles, i.e., interconnection, information transparency, automation, decentralized decisions and sustainability, can become a source of competitive advantage for utilities. This study helps place the physical assets portfolio at the core of strategic decisions aimed at attaining a more sustainable state, operational excellence, and economic prosperity

Fluvius drives towards sustainability: A case on rare earth elements (Ree) supply integrity

As Supply Chain Manager at Fluvius, the Belgian distribution system operator, Gunther wants to formulate a plan that can generate incentives to move towards greater energy supply chain sustainability and resilience. The low-carbon energy transition relies on rare earth elements (REEs)-enabled technologies tainted by their harsh mining ecosystem effects and their Chinese policies dependence. Gunther, adopting a holistic approach, analyses the complexity of the global, green energy supply chain. What does a sustainable energy supply chain actually mean? How to create a cascade of sustainable practices that reaches first-tier suppliers? How to couple resilience and sustainability and contribute to sustainable development? This case is designed to be exposed in Business Administration, Energy Management, Supply Chain Management, Operations Management or Technology Management courses. The goal is to develop and practice skills in identifying trends and weaknesses in a dynamic supply chain and to formulate an action plan that can integrate sustainability and resilience across an organization's supply chain

Managing physical assets: A systematic review and a sustainable perspective

Contemporary organisations recognise the need for Anthropocene disruptions and transform their business models, restructure their operations, and re-engineer their supply chains to attain greater sustainable objectives and a strong ESG (environmental-social-governance) proposition. Indeed, physical asset management shifted from the negative image associated with asset failure, expensive maintenance, and decommissioning to an enabler of sustainability that allows us to create and capture value from extended lifetime, renewed functions, and increased awareness. In this direction, this study follows a systematic reviewing process enabled by text analytics methods to identify the means and approaches to build a sustainable perspective for physical asset management. Our key contributions and insights are supported by statistics and key features extracted from over 2800 journal articles. We particularly emphasise the research footprint, the evolution, and research trends of the two most asset-intensive sectors (i.e. construction and energy) represented as barri ers and enablers of sustainable development. Lacking a unified perspective of the field, this study proposes a conceptual framework that adopts an asset-within-a-system perspective, recognises the links between the stakeholders and holistically integrates the extracted research trends. The knowledge provided here positions physical asset management as a key resource in achieving competitive the advantage in the framework of sustainable developmen