Ecological Footprint Research Articles

Artisanal gold mining in guinea and security concerns

One of the continents richest in gold reserves is Africa. According to the World Bank, about 20 % of gold in African countries is still mined using artisanal methods. There is no officially recognized, generally accepted definition of artisanal small-scale gold mining. In essence, artisanal or small-scale gold mining is a labor-intensive, financially and technologically underdeveloped gold mining activity. Artisanal gold mining can be either informal, illegal, without state permission, or formal (legalized, streamlined). In the modern world, artisanal mining in African countries is experiencing rapid growth after their liberation from colonial oppression. The paper examines the environmental costs or ecological footprint of artisanal gold mining, such as: mercury intoxication of ecosystems, gold miners and local populations; deforestation, destruction of ecosystems; pollution of watercourses; industrial injuries and occupational diseases of gold miners; crime and social instability. Practical recommendations for improving safety are given.

Nano Fertilizers: New Vistas towards Sustainable Agriculture and Climate Change Mitigation: A Review

To ensure the food and nutritional security of the burgeoning global population, food production needs to be doubled in developing countries by 2050. Currently, 30-40% of agriculture production predominantly relies on chemical fertilizers. Precise crop nutrition, low nutrient efficiency, maintaining soil fertility, less damage to soil flora and minimal environmental footprint are the major challenges in modern agriculture. Recent developments in the application of nanotechnology to produce agriculture inputs emerged as a sustainable solution for addressing the challenges in modern intensive agriculture by replacing synthetic bulk fertilizers with their nanoparticle size ( less than 100 nm), superior properties and smart delivery system. Nano fertilizers had the potential to fulfill the requirements of plant nutrition along with imparting sustainability in crop production without compromising the yield of the crops. Some of the current research studies have been reviewed in this paper with citation and these results showed that nano fertilizers have a substantial effect on plant growth, development and physiological parameters including chlorophyll content and photosynthetic activity, it depends on their composition, method and time of application. Their enhanced nutrient use efficiency, correlated with mitigating greenhouse gas emissions. Hence evolving as a cutting-edge approach for sustainable agriculture in climate change is enlightened in this review.

Influence of the recycled sand on the cement mortars

In construction, a recent direction is to examine and integrate alternative sources of building materials with the goal of substituting the use of natural materials. This transition is encouraged by growing concern among policymakers and researchers regarding the environmental footprint of the construction industry. The incorporation of recycled aggregates into cementitious materials, such as concrete or mortar, results in a deterioration of their mechanical performance and their durability. Scientific studies devoted to recycled concrete have demonstrated that it is affected by the introduction of these recycled aggregates, in particular by the use of recycled sand. The latter is characterized by the presence of significant proportions of hardened cement, particularly that coming from a recycling plant. In this work, we aim to study experimentally the influence of the nature of recycled sand on the properties of cement mortars, substituting natural sand, with different percentages by volume: 0, 15, 30, 40, 50 and 75 %, by two types of recycled sand, one from the crushing of structural concrete and the other from a recycling plant. The mortar mixtures were made from CEM I 52.5 and Sand/Cement ratio = 3. The plasticity of these mortars was kept constant and the recycled sands have been pre-wetted. The comparative study between the different compositions of recycled mortars has shown that the physical and mechanical properties are influenced by the incorporation rate of the recycled sand. Of which, increases in the compressive strengths of recycled mortars were recorded, particularly those based on sand from the crushing of structural concrete, compared to the control mortar based on natural river sand. However, the flexural strengths of the recycled mortars suffered a slight reduction compared to the reference mortar.

The Use of Lightweight Aggregates in Geopolymeric Mortars: The Effect of Liquid Absorption on the Physical/Mechanical Properties of the Mortar

Geopolymers have been proposed as a green alternative to Portland cement with lowered carbon footprints. In this work, a geopolymeric mortar obtained using waste materials is studied. Fly ash, a waste generated by coal combustion, is used as one of the precursors, and waste glass as lightweight aggregates (LWAs) to improve the thermal performance of the mortar. The experimental study investigates the effect of varying the alkali activating solution (AAS) amount on the workability, compressive strength, and thermal conductivity of the mortar. Indeed, AAS represents the most expensive component in geopolymer production and is the highest contributor to the environmental footprint of these materials. This research starts by observing that LWA absorbs part of the activating solution during mixing, suggesting that only a portion of the solution effectively causes the geopolymerization reactions, the remaining part wetting the aggregates. Three mixes were investigated to clarify these aspects: a reference mix with a solution content calibrated to have a plastic consistency and two others with the activating solution reduced by the amount absorbed by aggregates. In these cases, the reduced workability was solved by adding the aggregates in a saturated surface dry state in one mix and free water in the other. The experimental results evidenced that free water addiction in place of a certain amount of the solution may be an efficient way to improve thermal performance without compromising the resistance of the mortar. The maximum compressive strength reached by the mortars was about 10 MPa at 48 days, a value in line with those of repair mortars. Another finding of the experimental research is that UPV was used to follow the curing stages of materials. Indeed, the instrument was sensitive to microstructural changes in the mortars with time. The field of reference of the research is the rehabilitation of existing buildings, as the geopolymeric mortars were designed for thermal and structural retrofitting.

High-order simulation of geological domains and effects on stochastic long-erm planning of mining complexes

Stochastic long-term mine planning has evolved to account for different sources of uncertainty. Typically, the uncertainty and local variability of boundaries in geological domains have been overlooked by experts through their deterministic interpretation of available data. Categorical attributes are used to model geological domains, and their stochastic simulation accounts for the mentioned issues. The ability of two-points simulation methods to reproduce complex patterns or the requirement of a training image in multiple-points simulation methods has limited their implementation in mining environments. The high-order simulation of categorical attributes presents a mathematically consistent framework that overcomes these limitations by using high-order spatial statistics from sample data. The case study at a gold mining complex shows two stochastic mine plans based on two sets of geological realisations: geological domains in the first set are modelled using conventional wireframes, while, in the second, they are simulated through the high-order method. The resulting mine plans are substantially different; while both plans present a similar quantity of metal recovered and lifespan, risk profiles are up to 40% wider, and the expected NPV is 20% higher for the case of simulated geological domains, given the decrease of waste handling costs and the corresponding reduction in environmental footprint.

Global assessment of effective population sizes: Consistent taxonomic differences in meeting the 50/500 rule.

Effective population size (Ne) is a particularly useful metric for conservation as it affects genetic drift, inbreeding and adaptive potential within populations. Current guidelines recommend a minimum Ne of 50 and 500 to avoid short-term inbreeding and to preserve long-term adaptive potential respectively. However, the extent to which wild populations reach these thresholds globally has not been investigated, nor has the relationship between Ne and human activities. Through a quantitative review, we generated a dataset with 4610 georeferenced Ne estimates from 3829 populations, extracted from 723 articles. These data show that certain taxonomic groups are less likely to meet 50/500 thresholds and are disproportionately impacted by human activities; plant, mammal and amphibian populations had a <54% probability of reaching = 50 and a <9% probability of reaching = 500. Populations listed as being of conservation concern according to the IUCN Red List had a smaller median than unlisted populations, and this was consistent across all taxonomic groups. was reduced in areas with a greater Global Human Footprint, especially for amphibians, birds and mammals, however relationships varied between taxa. We also highlight several considerations for future works, including the role that gene flow and subpopulation structure plays in the estimation of in wild populations, and the need for finer-scale taxonomic analyses. Our findings provide guidance for more specific thresholds based on Ne and help prioritise assessment of populations from taxa most at risk of failing to meet conservation thresholds.

Influence of the Depth of Nitrogen-Phosphorus Fertilizer Placement in Soil on Maize Yielding and Carbon Footprint in the Loess Plateau of China

Deep fertilization is a beneficial approach for reducing nitrogen losses. However, the effects of various fertilization depths on maize (Zea mays L.) productivity and environmental footprints have not been thoroughly understood. Therefore, a field experiment was conducted to investigate the effects of different fertilization depths of 5 cm (D5), 15 cm (D15), 25 cm (D25), and 35 cm (D35) on maize productivity and environmental footprints. Reactive nitrogen (Nr) losses and greenhouse gas (GHG) emissions were assessed using life cycle analysis. We hypothesized that deep fertilization can obtain lower carbon and nitrogen footprint. The results indicated that deep fertilization decreased the N2O and NH3 emissions while increasing the CH4 uptake. Compared with D5, D15 resulted in an increase in total GHG emissions and carbon footprint (CF), whereas D25 decreased by 13.0% and 23.6%, respectively. Compared with D5, the Nr losses under D15, D25, and D35 conditions was reduced by 11.3%, 17.3%, and 21.0%, respectively, and the nitrogen footprint (NF) was reduced by 16.0%, 27.4%, and 19.0%, respectively. The maize yield under D15 and D25 increased by 5.7% and 13.8%, respectively, compared with the D5 treatment, and the net economic benefits of the ecosystem increased by 7.1% and 17.1%, respectively. In summary, applying fertilizer at a depth of 25 cm can significantly reduce the environmental footprints and increase maize productivity, making it an effective fertilization strategy in the Loess Plateau region of China.

The carbon footprint of as-needed budesonide-formoterol in mild asthma: a post hoc analysis.

The use of pressurised metered-dose inhalers (pMDIs) and asthma exacerbations necessitating healthcare reviews contribute substantially to the global carbon footprint of healthcare. It is possible that a reduction in carbon footprint could be achieved by switching patients with mild asthma from salbutamol pMDI reliever therapy to inhaled corticosteroid-formoterol dry powder inhaler (DPI) reliever therapy, as recommended by the Global Initiative for Asthma (GINA). This post hoc analysis included all 668 adult participants in the Novel START trial, who were randomised 1:1:1 to treatment with: as-needed budesonide-formoterol DPI, as-needed salbutamol pMDI, or maintenance budesonide DPI plus as-needed salbutamol pMDI. The primary outcome was carbon footprint of asthma management, expressed as kilograms of carbon dioxide equivalent emissions (kgCO2e), per person year. Secondary outcomes explored the effect of baseline symptom control and adherence (maintenance budesonide DPI arm only) on carbon footprint. As-needed budesonide-formoterol DPI was associated with 95.8% and 93.6% lower carbon footprint compared with as-needed salbutamol pMDI (least squares mean 1.1 versus 26.2 kgCO2e; difference -25.0, 95% CI -29.7 to -20.4; p<0.001) and maintenance budesonide DPI plus as-needed salbutamol pMDI (least squares mean 1.1 versus 17.3 kgCO2e; difference -16.2, 95% CI -20.9 to -11.6; p<0.001), respectively. There was no statistically significant evidence that treatment differences in carbon footprint depended on baseline symptom control or adherence in the maintenance budesonide DPI arm. The as-needed budesonide-formoterol DPI treatment option was associated with a markedly lower carbon footprint than as-needed salbutamol pMDI and maintenance budesonide DPI plus as-needed salbutamol pMDI.

Efficiency of CONTRAfluran™ in reducing sevoflurane pollution from maintenance anaesthesia in minimal flow end-tidal control mode for laparoscopic surgery.

Recommendations exist that aim to mitigate the substantial ecological impact of anaesthesia. One option is to use anaesthetic gas capturing technology at anaesthesia workstation exhausts to harvest and recycle volatile agents. However, the efficiency of such technology is mainly unverified in vivo. The efficiency of CONTRAfluran™ in capturing sevoflurane from an anaesthesia workstation exhaust (when set to minimal flow and end-tidal control mode) was evaluated in 70 adult patients scheduled for general or bariatric laparoscopic surgery. The weight of the sevoflurane vaporiser and CONTRAfluran canister was measured before and after each case, to calculate total sevoflurane consumption and retention. Retention was measured after the minimal flow maintenance phase and after the high flow washout phase. The total retention efficiency was the fraction of all consumed sevoflurane captured by the CONTRAfluran canister. The primary objective was to examine the retention efficiency of CONTRAfluran in a clinical surgical setting, where all feasible strategies to minimise sevoflurane consumption and optimise the efficacy of CONTRAfluran were utilised. The secondary objective was to analyse the correlation between mass transfer and the duration of the case. Mean (SD) volume of sevoflurane captured using CONTRAfluran was 4.82 (1.41) ml, representing 45% (95%CI 42-48%) of all sevoflurane administered. The highest amount of retention was found during the washout phase. Retention efficiency did not correlate with the duration of the case. Over half of the sevoflurane administered was not captured by the CONTRAfluran canister when minimal flow techniques were used, likely due to residual accumulation of sevoflurane in the patient after tracheal extubation or, to a lesser extent, due to ventilation system leakage. However, as every prevented emission is commendable, CONTRAfluran may be a potentially valuable tool for reducing the environmental footprint of sevoflurane-based anaesthesia.

Toward sustainable climate action in advanced economies: Linking information communication technology, technological innovation, economic complexity, and ecological footprint

AbstractInformation and communication technology (ICT), technological innovation, and renewable energy (REN) consumption have been proffered as solutions to the recent environmental tragedies in developed countries. In recent times, ICT diffusion and technological innovation have improved in G7 countries, but the same cannot be said of REN consumption. As such, this study examines the link between ICT, economic complexity, technological innovation, REN, and ecological footprint (EF) for G7 countries over the period 1990–2020. We use three variables (fixed telephone subscriptions [FTS], mobile cellular subscriptions [MCS], and individuals using the internet [IUI]) to represent ICT. The presence of cross‐sectional dependence guides the use of second‐generation econometric methods for slope heterogeneity, unit root, cointegration, and parameter estimation. The augment mean group (AMG) estimator and panel OLS techniques are applied to complement the method of moment quantile regression (MM‐QR) approach. The MM‐QR results suggest that REN consumption and technological innovation impede the EF across all quantile levels (0.1–0.9), whereas economic growth and economic complexity augment the EF in G7 countries. The ICT variables have heterogeneous effects on the EF, suggesting that the impact of ICT on the EF depends on the estimation techniques and proxy for the variable. In line with these outcomes, public policies directed toward funding technological innovation projects are recommended. The funding should specifically focus on environmentally friendly technologies that can guarantee complementarity between reduced environmental damage and increased economic growth.

Design for the environment: SHJ module with ultra‐low carbon footprint

AbstractThe photovoltaic (PV) industry is reaching an inflection point to become a major source of energy. Last decades brought important technical progression in modules' yield and durability. Already available technical solutions might reach the highest power output and the lowest environmental impact in a module. Nevertheless, cost remains the major driver for innovation; top PV panels must combine cost/delay/yield to reach reasonable market share. Our paper presents the development of silicon heterojunction (SHJ) modules with exemplary power and reliability with significantly reduced environmental impact and components sourced from Europe. In order to guide the technology choice in the design phase, we performed a Life Cycle Assessment (LCA) sensitivity study. For a standard PV module, we identify the main steps to improve in order to reduce its environmental footprint. This guided us to tackle the components with the highest impact on the carbon footprint, namely the wafer, glass front sheet and aluminium frame. The proposed improvements will be tested from technical and economic point of view and assembled within one PV module. At the cell scale, we achieved the reduction of the carbon footprint by reducing the thickness of the wafers issued from the European value chain. Optimisation of metallisation and cell interconnection has limited the consumption of silver (Ag), a critical raw metal. At the module level, we implemented the reduction of glass thickness and the replacement of the aluminium frame with a natural fibre‐based frame in a glass‐backsheet module configuration. In addition, we applied a ‘design for recycling’ approach for the choice of encapsulant and backsheet. The combination of these innovations led us to the realisation of a 566‐Wp recyclable module using a tiling interconnection, cells with an average efficiency of 22.57% with a carbon footprint of 313 kgCO2eq/kWp.

A comparative study on the combination of life cycle assessment and ecological footprints: solar photovoltaic power generation vs. coal power generation in Ningxia

In China, where energy activities, predominantly driven by fossil fuel combustion, account for nearly 90% of the country’s greenhouse gas (GHG) emissions and coal power alone contributes over 40%, the shift towards carbon neutrality is a critical national ambition. This study conducts a comprehensive comparison of the environmental impacts of solar photovoltaic power generation (SPPG) and coal power, employing both life cycle assessment and ecological footprint analysis. We meticulously analyze the complete lifecycle of SPPG, pinpointing key stages of GHG emissions, and offer nuanced, localized policy recommendations. Our findings indicate that a 1 kWp SPPG module emits 1,601.18 kg of GHGs over its lifespan, equating to 1.35 kg/kW·h per unit of electricity produced—substantially lower than the 4.81 kg/kW·h emitted by coal power, thus highlighting the latter’s heightened environmental detriment. Additionally, this study assesses the ecological footprint of both energy sources in Ningxia. SPPG emerges with an ecological surplus, showcasing a per capita footprint of 0.0342 hm2, compatible with Ningxia’s ecological capacity. In stark contrast, coal power exhibits a sustained ecological deficit over the past 5 years, with a growing per capita footprint of 0.6529 hm2, underscoring its unsustainability. This research provides a detailed comparative analysis of the environmental impacts of SPPG and coal power in Ningxia, offering valuable insights for energy policymakers and industry stakeholders. It underscores the urgent need for industrial restructuring towards more sustainable and renewable energy sources, aligning with China’s broader objectives of environmental preservation and achieving carbon neutrality.

Embracing Sustainable Living : Modern Trend in Architecture

Our planet is currently confronted with a mounting number of environmental challenges, which necessitate a shift towards sustainable living practices. As a significant contributor to our ecological footprint, architecture is transforming in response to this. This paper examines how modern architectural trends are embracing sustainability. It delves into the core principles of sustainable design and analyses specific trends, such as passive design, renewable energy integration, and biophilic design, and their impact on the environment, human health, and resource conservation. Additionally, the paper addresses various challenges, such as initial costs and public awareness. Finally, the paper explores the future of sustainable architecture, including advances in materials and technologies, net-zero energy buildings, and sustainable urban planning. The research highlights the potential of modern architecture to create a more sustainable built environment for the future.

UAV-based solution for extending the lifetime of IoT devices: efficiency, design and sustainability

Internet of Things technology is named as a key ingredient in the evolution towards digitization of many applications and services. A deployment based on battery-powered remote Internet of Things (IoT) devices enables easy installation and operation, yet the autonomy of these devices poses a crucial challenge. A too short lifespan is undesirable from a functional, economical, and ecological point of view. This paper presents a unmanned aerial vehicle (UAV)-based approach to recharge remote Internet of Things (IoT) nodes. An in-depth study of the charging efficiency and optimization of key parameters, and measurements-based verification, is reported on. An actual corresponding design and implementation of the full UAV-based charging system and its proof-of-concept validation are presented. Finally, the sustainability of the proposed solution is discussed. The results presented in this paper hence confirm that the proposed UAV-based approach and design are functionally successful and efficient charging can be achieved, provided the constraints and challenges coming with the approach are adequately dealt with. Moreover, it comes with an overall reduction in ecological footprint for IoT applications relying on battery-powered nodes in need of medium energy and/or considerable lifetime expectation (5 years or more).

Response Surface Optimization of Rice and Guinea Corn Husk Ash Blended Concrete

Concrete, a fundamental construction material, consists of aggregates, water, cement, and additives. Unfortunately, the large-scale production of cement is a major contributor to carbon dioxide (CO2) emissions, primarily from the manufacturing process and the consumption of fossil fuels. This not only incurs environmental costs associated with global warming but also depletes vital limestone deposits. To mitigate these issues, this study aims to explore the optimal utilization of Guinea Corn Husk Ash (GCHA) and Rice Husk Ash (RHA) in concrete. This research investigated the chemical properties of GCHA and RHA, and their impact on the compressive and split-tensile strengths of concrete when integrated in various proportions. The study reveals that both GCHA and RHA meet the minimum oxide content requirement of 70% set by ASTM C618, with silicon dioxide (SiO2) as the predominant oxide. Increasing the content of RHA and GCHA from 5% to 10% improves the concrete's compressive and split-tensile strengths after curing for 56 days. Optimization results indicate that the ideal mix consists of 10% GCHA, 8.5% RHA, and 82.5% cement, yielding a compressive and split tensile strength of 31.34 N/mm² and 3.07 N/mm² respectively. This study thus offers a promising solution for sustainable concrete production by reducing the environmental footprint of cement while enhancing material properties and promoting an eco-friendlier approach to construction. Keywords: Concrete, Guinea Corn Husk Ash, Rice Husk Ash, Compressive Strength, Split-Tensile Strength

Algae as an alternative source of protein in poultry diets for sustainable production and disease resistance: present status and future considerations

Integrating algae into poultry diets offers a promising avenue for enhancing nutrition, boosting sustainability efforts, and potentially stimulating disease resistance. This comprehensive review delves into the essence, diversity, chemical composition, and nutritional merits of algae, spotlighting their emergence as innovative nutrient sources and health supplements for poultry. The growing interest in algae within poultry nutrition stems from their diverse nutritional profile, boasting a rich array of proteins, lipids, amino acids, vitamins, minerals, and antioxidants, thus positioning them as valuable feed constituents. A key highlight of incorporating both macroalgae and microalgae lies in their elevated protein content, with microalgae varieties like Spirulina and Chlorella exhibiting protein levels of up to 50–70%, outperforming traditional sources like soybean meal. This premium protein source not only furnishes vital amino acids crucial for muscular development and overall health in poultry but also serves as an exceptional reservoir of omega-3 fatty acids, notably eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), presenting multiple health benefits for both poultry and consumers alike. Moreover, algae boast antioxidant properties attributed to bioactive compounds like phycocyanin and astaxanthin, mitigating oxidative stress and boosting the bird’s immune response, thereby fostering robust health and disease resilience. Incorporating macroalgae and microalgae into poultry diets yields positive impacts on performance metrics. Research evidence underscores the enhancement of growth rates, feed conversion ratios, carcass quality, and meat attributes in broilers, while in layers, supplementation promotes increased egg production, superior egg quality, and increased concentrations of beneficial nutrients such as omega-3 fatty acids. Furthermore, algae hold promise for mitigating the environmental footprint of poultry production, though significant outcomes from trials remain sporadic, necessitating further research to elucidate optimal dosages and blends for different algae species in poultry diets. Standardizing the composition of algae utilized in research is imperative, paving the way for potential applications in poultry nutrition as growth stimulants and substitutes for antibiotics. Nonetheless, a deeper understanding of dosage, combination, and mechanism of action through rigorous scientific investigation is key to unlocking algae’s full potential within poultry nutrition.

Valuation entrepreneurship through product‐design and blame‐avoidance strategies: How Tesla managed to change the public perception of sustainable innovations

AbstractDeveloping innovative, eco‐friendlier products that gain traction in the mass market remains a persistent challenge for many firms. To bring consumers to choose “greener” alternatives over conventional products, firms need to overcome prevailing product evaluations that favor traditional solutions. Research on valuation entrepreneurship examines the strategies that actors apply to induce changes in established evaluations. Adding to the emerging literature on valuation entrepreneurship, our study analyzes how the car maker Tesla, Inc. used product design—material artifacts' properties of form and function—to advance the public perception of battery electric vehicles (BEVs). When Tesla entered the market, several firms had tried to promote BEVs as a way of making private mobility more environmentally friendly, but with limited success. In contrast, Tesla produced well‐received BEVs that generated enormous consumer interest and led to a more favorable assessment of BEVs as a whole. Drawing on 54 interviews and nearly 2000 pages of archival data, our abductive study identifies three product design strategies that increased the appeal of Tesla's initial models: (1) incorporating discontinuous technological solutions; (2) optimizing the products on traditional evaluation criteria (e.g., driving performance, comfort, space, status); and (3) creating an ecosystem of complementary products. Since some design choices came at the expense of a minimal environmental footprint, they risked attracting blame for compromising on the environmental performance of potentially eco‐friendly cars and for committing “greenwashing.” To minimize this risk, Tesla complemented its design strategies by employing three strategies of reputational politics to avoid such blame. After Tesla's initial, lavish models had improved the public perception of electric cars, Tesla and other car makers were able to sell less excessive and more sustainable BEVs in much greater quantities than ever before. Our findings contribute to three literature streams and generate valuable insights for management practice.

Forecasting the ecological footprint of G20 countries in the next 30 years

The Ecological Footprint evaluates the difference between the availability of renewable resources and the extent of human consumption of these resources. Over the past few decades, historical records have shown an accelerated decline in the availability of resources. Based on national footprint and biocapacity accounts, this analysis aims to advance the forecasting of the G20 countries' ecological footprints over a 30-year time frame. We employed a time series forecasting approach implemented in Python, which included-modular regression (Prophet) and Autoregressive Integrated Moving Average (ARIMA & Auto-ARIMA) methods. We evaluated and combined the performance of these three methods. The results indicated that among the largest economies of the G20, only four countries are projected to have a positive ecological footprint balance by 2050. These countries share the common denominator of large land areas and a moderate population growth projection. However, the overall trend of the indicator suggests that it will continue to decline.

Vapor-induced phase-separation-enabled versatile direct ink writing

Versatile printing of polymers, metals, and composites always calls for simple, economic approaches. Here we present an approach to three-dimensional (3D) printing of polymeric, metallic, and composite materials at room conditions, based on the polymeric vapor-induced phase separation (VIPS) process. During VIPS 3D printing (VIPS-3DP), a dissolved polymer-based ink is deposited in an environment where nebulized non-solvent is present, inducing the low-volatility solvent to be extracted from the filament in a controllable manner due to its higher chemical affinity with the non-solvent used. The polymeric phase is hardened in situ as a result of the induced phase separation process. The low volatility of the solvent enables its reclamation after the printing process, significantly reducing its environmental footprint. We first demonstrate the use of VIPS-3DP for polymer printing, showcasing its potential in printing intricate structures. We further extend VIPS-3DP to the deposition of polymer-based metallic inks or composite powder-laden polymeric inks, which become metallic parts or composites after a thermal cycle is applied. Furthermore, spatially tunable porous structures and functionally graded parts are printed by using the printing path to set the inter-filament porosity as well as an inorganic space-holder as an intra-filament porogen.

Tackling the Beast – How to Assess Scope 3 Emissions

The transparent and valid measurement of Scope 3 emissions (indirectly caused emissions upstream and downstream) represents one of the greatest challenges for companies during their sustainable transformation. In order to assess the current performance of a company and to derive the necessary action steps, it is essential to have the best possible knowledge of the current emissions. However, especially in the area of Scope 3, companies are dependent on external information and are not in a position to independently determine the ecological footprints of upstream purchased materials, products and services and the downstream emissions caused by products and services sold. This publication provides an overview of current main challenges and complexities deriving from the assessment of Scope 3 emissions and highlights the most suitable approaches to achieve best possible results.