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Graphene oxide (GO) has attracted significant attention due to its unique optical properties and tunable surface chemistry, making it an excellent platform for optical sensing applications. Combining GO with metallic nanoparticles allows for the fabrication of highly sensitive surface-enhanced Raman scattering (SERS) substrates for analytical purposes. Here, we report our research on chemical strategies to decorate GO paper with Au nanostars (AuNSs) for the SERS detection of methylene blue, a water pollutant model. Several preparative approaches were employed to evaluate their sensitivity to detect MB molecules, including polyelectrolytes, distinct graphene-based materials, and the deposition method of the AuNSs. [ABSTRACT FROM AUTHOR]

This paper describes all the characteristics of the Guatemalan earthquake catalog and how it has evolved. Over 64,483 earthquakes are included in this paper distributed in some areas of El Salvador, Mexico, Honduras, and Belize, but mainly in Guatemala. Regularly, the earthquake catalogs improve their characteristics over time, however, this is not the case for the catalog of Guatemala. Although earthquake detection improved with the establishment of the national seismic network operated by the National Institute of Seismology, Vulcanology, Meteorology and Hydrology (INSIVUMEH) in 1977, the catalog has not kept a favorable evolution over time. This has led to problems with earthquake detection, large location errors, increasing magnitude of completeness, and others that are going to be discussed later in this paper. [ABSTRACT FROM AUTHOR]

In this work, we focused on Electrospray (ES) and Ultrasonic Spray Coating (USC) as two promising and innovative fabrication techniques for the optimisation of carbon electrode surfaces to be employed in Bio-Electrochemical Systems. We performed, on commercial carbon paper electrodes, controlled depositions of a nanostructured layer containing PEO and PEDOT:PSS. We then employed electron microscopy and Raman spectroscopy to characterise the morphology and superficial uniformity of the so-obtained electrodes. Together with electrochemical characterisations and experiments in bio-electrochemical devices, we demonstrated how ES and USC represent promising techniques for the optimisation of carbon electrodes' surfaces, obtained with the deposition of a conductive nanostructured layer. [ABSTRACT FROM AUTHOR]

Return periods (Ts) are used to estimate the interval of time between natural hazard occurrences of a certain size and assess the risks associated with hydrological occurrences, climate extremes, structural failures and seismicity. Despite Ts being widely used, they are characterized by strong misconceptions and ambiguities. Moreover, although they have been successfully used when discussing storm surges, high tides and extreme precipitation, concerns arise from their use in assessing probabilities of future global mean sea level rise (SLR). Most papers discuss SLR return periods considering storm surges or high tides and not SLR itself, as a separate and unique hazard. Sea level rise due to storm surges or tides is regional and temporary and differs from the global SLR, which is a long lasting and slow phenomenon. This paper discusses these misconceptions and misuses of return periods in assessing flood risk and the probability of sea level rise at the global level and suggests a method for assessing likelihoods of climate change risks that can be widely accepted and commonly used by all stakeholders and decision makers for all types of climate hazards. [ABSTRACT FROM AUTHOR]

By combining blockchain with physical tracking technologies, raw materials can potentially be traced throughout their global supply chains. Physical tracking technologies enable observing how raw materials move within the physical world, whereas blockchain translates these events into the digital world with an immutable record. This paper presents a taxonomy of different physical tracking technologies and examines if and how the combination of these technologies render raw material supply chains more transparent. Although academic literature highlights the theoretical benefits of combining these transformative technologies, large scale projects are still in their early stages. Following a brief literature review, this paper leverages an empirical approach to classify different tracking technologies, their fields of application and limitations, as well as how these technologies can enable supply chain transparency. Obviously, there is no single technology that can fulfil all requirements along complex supply chains. However, the relevant combination of respective technologies can help bridge gaps by increasing transparency within supply chains. [ABSTRACT FROM AUTHOR]

This paper surveys the historical indigenous water-harvesting and water-supply systems in the Levant, focusing on Syrian lands, where they are numerous and well-preserved. It also deals with the important hydraulic works recently carried out to exploit the area in terms of agriculture to preserve, supply and collect water. Furthermore, the paper's scope is to evaluate the feasibility of rehabilitating ancient hydraulic structures, either by maintaining the old systems or by implementing new projects. [ABSTRACT FROM AUTHOR]

The potential for the generation of pico- and micro-hydropower through hydraulic energy recovery has been demonstrated across many sectors of the water-energy-food nexus, often termed hidden hydropower. The potential to recover energy from hidden hydropower in water supply, crop production, food processing, and energy production has been demonstrated via numerous in-depth case studies, regional assessments, and physical experiments. This paper presents a holistic overview of the potential role and impacts of micro-hydropower energy recovery on the water-energy-food nexus in the context of climate change. The paper comprises a review and synthesis of the available literature. The paper outlines the potential impacts of hidden hydropower on cost of water supply, energy and food production, considering also the potential impacts on crop yield and food supply. Policy and technological barriers to the exploitation of hidden hydropower resources within the nexus are outlined and recommendations to overcome these are provided. The results of this investigation highlight the potential of micro-hydropower energy recovery in water systems to reduce energy consumption by 0.005–3.7% across various sectors and regions, with consequent impacts in the operating and consumer costs of food, water and energy, as well as on the CO2 emissions of these activities. This hidden hydropower has the potential to ease the pressures of the water-energy-food nexus and is an important element of the route towards sustainability within the nexus. [ABSTRACT FROM AUTHOR]

Nowadays, most industrial solid waste, agriculture waste, and natural minerals are piled up, which not only occupies land resources, but also has a dangerous impact on the environment. The responsible management and recycling of these materials can have significant environmental benefits, while also providing a means of accessing raw materials for the creation of geopolymers. Geopolymers are new, environment-friendly, cementless materials and alternative construction materials to ordinary Portland cement. They not only have excellent mechanical properties, but also have valuable properties, e.g., high-temperature resistance. This paper summarizes the feasibility studies in terms of base materials and properties of today's developing geopolymers. This paper also highlights the significance of developing sustainable materials for civil engineering. [ABSTRACT FROM AUTHOR]

The application of curved Insulating Glass Units (IGUs) in facades has emerged as a novel solution to meet aesthetic and energy performance objectives. Due to improved stiffness, curved IGUs cannot equalise internal and atmospheric pressure changes by pillowing, as flat IGUs do. Thus, the climatic loads in curved IGUs may be several times higher than those in flat units. This paper deals with experiments and numerical simulations of cylindrically curved IGUs. It presents the results of an experimental campaign designed to collect data that validate the numerical model of a curved IGU developed within this study. The model is sequentially used to analyse a case study that compares the resulting internal pressure, displacement, and stress in glass in a flat and curved IGU subjected to the characteristic climatic actions given by DIN18008-1. [ABSTRACT FROM AUTHOR]

The feedback from international practice has shown that the installation of photovoltaic (PV) parks on abandoned dumps is one of the best environmental and economical solutions. This paper discusses the site selection criteria for the installation of PV systems on dumps. When installing the PV systems, different environmental, technical, and economic criteria should be respected. The ground movement and combustion hazards in the dumps appear to be the main constraints and limitations for the installation of photovoltaic panels. This paper presents several examples of the installation of photovoltaic panels on coal-lignite dumps in France. However, the number of projects is still very limited compared to the identified potential. [ABSTRACT FROM AUTHOR]

This paper presents a discussion on Quebec's pegmatite lithium resources and potential markets. It also evaluates the opportunities of lithium battery production for electric vehicles (EV) in the province while reducing greenhouse gas emissions. The paper shows that mining Quebec's lithium ore deposits would be sufficient to satisfy the province's lithium demand and also for exporting abroad lithium-ion batteries. By considering only the projects whose final product is LMH or LCE, Quebec would be able to produce between 10 and 21 million lithium-ion batteries for electric vehicles with a greenhouse gas emissions footprint of only 43% of the international average value due to Quebec's hydro power. Finally, considering Quebec's lithium mining project economics, the increased future demand for lithium would render Quebec's lithium pegmatite projects competitive compared with those reported for brine projects. [ABSTRACT FROM AUTHOR]

Machine learning is constantly gaining ground in the mining industry. Machine learning-based systems take advantage of the computing power of personal, embedded and cloud systems of today to rapidly build models of real processes, something that would have been impossible or extremely time-consuming a couple of decades ago. The widespread access to the internet and the availability of cheap and powerful cloud computing systems led to the development and acceptance of tools to automate resource modelling processes or optimise mine scheduling, using machine learning methodologies. The domain modelling system discussed in this paper, called DomainMCF, has been developed by Maptek, using artificial neural network technology. In the application presented in this paper, DomainMCF is used to model the spatial distribution of marble quality categorical parameters, and the results are combined to produce a final marble quality classification using drillhole and quarry face samples from an operational marble quarry in NE Greece. DomainMCF was made available for this study as a cloud processing service through an early access program for individuals or companies interested in testing its capabilities and suitability in various modelling scenarios and geological settings. The resulting marble product classifications are compared with those produced by the already established classification system that is based on a more conventional estimation method. The produced results show that DomainMCF can be effectively applied to the modelling of marble quality spatial distribution and similar domaining problems. [ABSTRACT FROM AUTHOR]

Greece is gifted with geologic features that promote geothermal heat flow. Geothermal energy exploration began in the late 60s, culminating in the first geothermal energy law in 1984 and the introduction of geothermal energy as a mineral resource under the amendment of the Greek Mining Code. Since then, low- and high-temperature geothermal activities followed their separate ways, with a modest utilization of the energy product in the primary sector (agriculture, aquaculture) and attempts for electricity production stalled since the mid-1990s. The adoption of green policies by both the EU and Greece, the acceptance of global warming as an existing threat, the adhesion to CO2 reduction goals, energy efficiency and the application on renewable energy solutions as means to combat the increase in global temperature have led to an increasing interest in the utilization of the geothermal energy applications. This paper presents the new legal framework for geothermal energy established by Law 4602/2019, as introduced by the Greek Ministry of Environment and Energy, Directorate-General for Mineral Raw Materials and discusses its scope and goals set by the implementation of its provisions. The paper offers a roadmap to successfully test those new policies and regulatory provisions and, finally, it maps the interfaces of stakeholders and geothermal industry in an attempt to highlight the steps of the necessary administrative procedures towards the facilitation of viable geothermal projects. [ABSTRACT FROM AUTHOR]

Recycling plant-based materials for various applications not only reduces the harm to the environment but also presents an excellent green source for nanomaterial synthesis. Being chiral and biodegradable makes cellulose, which is an organic polymer, an economic and easy-to-access plant-derived green material. Cellulose can be synthesized into nanostructures for a vast array of high-demand applications, such as drug delivery; biomedicines, which includes "biosensors and diagnostics"; medical implants; skin tissue healing; wastewater treatment; touch screen technology; electronic skin; human–machine interfaces; flexible devices; energy storage devices; clothes; packaging; and cosmetics. The daily newspapers that are delivered to our homes can be one of the best sources of cellulose for us. Our work in this study concentrated on removing nanocrystalline cellulose from newspapers. To begin, we deinked the newspapers and then the deinked pulp was transformed into its nanostructures, or nanocrystalline cellulose, to achieve a high aspect ratio, on the one hand, using chemicals like NaOH, thiourea, etc., and on the other side, via a mechanical process. We used a variety of characterization techniques, including scanning electron microscopy to study morphological properties, X-ray diffraction, and dynamic light scattering for dimensional analysis, Fourier transforms infrared spectroscopy for thermogravimetric analysis, and others, to confirm that the synthesized materials had achieved the intended outcomes. A high aspect ratio enables us to create surfaces with a huge surface area with very little synthetic material. The final product, which was created by synthesis, has been discovered to have features that are identical to those of nanocrystalline cellulose, which is available for purchase in the market for use in laboratory purposes. To make nanocomposites, this nanocrystalline cellulose can be combined with various organic and inorganic polymers, which can be further used as a base material for energy storage devices. In this paper, we compared our materials at different time durations used in synthesis. [ABSTRACT FROM AUTHOR]