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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]

Nuclear power plays a significant role in fulfilling the energy needs of Pakistan and its share in the total energy mix has increased from 4.7% to 8.8% in the past seven years. As per the Pakistan energy outlook report (2021–2030), this share is hypothesized to increase to 10.82% by the year 2030, which will alleviate the energy shortage problem and, at same time, reduce carbon emissions. Like all thermal power plants, it is also necessary for nuclear plants to operate at optimum efficiency. This study is based on the thermodynamic analysis of the conventional side of an advanced HPR-1000 (PWR) nuclear power plant. In this paper, a comparison of indigenously developed model results is made, with vendor-provided sea water temperatures and power curves for year-long sea water temperature variation. Firstly, a computational model is developed using Engineering Equation Solver (EES) software to evaluate the performance of the secondary side of the plant and is validated based on the designer-provided heat balance analysis for full power mode. Then, the condenser heat balance is performed for different cooling medium inlet temperatures and terminal temperature differences to study the relationship of condenser performance, thermal efficiency, and output power. Initial results reveal that sea water temperature varies at the condenser inlet from 5 to 35 °C, the power output of the unit decreases by 54 MW, and the thermodynamic efficiency drops by 1.79%. Thus, this paper highlights the impact of sea water temperature on plant performance and the need to devise more effective techniques to approach the plant's optimum efficiency. [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]

The Hapke model has been widely used in the field of soil remote sensing. However, the latest development of the Hapke model (i.e., Hapke-HSR model) adopted a simple hypothesis to consider the influence of the soil moisture content (SMC), which brought great difficulties to SMC parameter inversion. This paper presents a method to improve the Hapke model using the improved multilayer radiative transfer model of soil reflectance (MARMIT-2), which can effectively improve the ability of the Hapke-HSR model to characterize the variation in the SMC. Finally, we used the soil database to comprehensively verify the ability of the improved Hapke model. The results show that the improved Hapke can effectively characterize the spectral characteristics of soil and show a higher fitting accuracy (RMSE = 0.009) compared with the Hapke-HSR model (RMSE = 0.031), especially at a high SMC (≥30%). Therefore, the improved Hapke model can better understand soil physical properties and improve the inversion accuracy of soil–vegetation physical parameters, which can be used to enhance agricultural water use efficiency. [ABSTRACT FROM AUTHOR]

This paper presents a meticulous exploration of advanced machine learning techniques for precise forest type classification using multi-temporal remote sensing data within a woodland environment. The study comprehensively evaluates a diverse range of models, ranging from advanced (ensemble) machine learning (ML) methods to several finely tuned support vector machine (SVM) variants, with a specific focus on Bayesian-optimized SVM with a radial basis function (RBF) kernel. Our findings highlight the robust performance of the Bayesian-optimized SVM, achieving a high accuracy of up to 94.27% and average precision and recall of 94.46% and 94.27%, respectively. Notably, this accuracy aligns with the levels attained by acclaimed ensemble techniques such as random forest and CatBoost while also surpassing those of XGBoost and LightGBM. These results highlight the potential of these methodologies to significantly enhance forest type mapping accuracy compared to traditional (linear) SVM and black-box neural networks. This, in turn, can enable the reliable identification and quantification of key services, including carbon storage and erosion protection, intrinsic to the forest ecosystem. The findings of our comparative study emphasize the profound impact of employing and fine-tuning ML approaches in the realm of remote sensing-based environmental analysis. [ABSTRACT FROM AUTHOR]

Lignin, a paper and pulp industry waste product, has attracted significant attention in recent years as a promising sustainable material for high-end energy applications. Herein, we examine lignin as a potential material for ionic thermoelectric hydrogels and carbon-based materials. Optimized lignin-derived hydrogels demonstrate a remarkable Seebeck coefficient of 3.63 mV/K when subjected to an axial temperature gradient. Furthermore, synthesized lignin-based porous carbon materials exhibit exceptional performance as supercapacitor electrodes, with a superior specific capacitance of 56.3 F/g at 0.5 A/g. Lignin-based hydrogels and porous carbon electrodes offer a promising path towards the development of lignin-derived ionic thermoelectric supercapacitors. [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]