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High-quality perovskite thin films are typically produced via solvent engineering, which results in efficient perovskite solar cells (PSCs). Nevertheless, the use of hazardous solvents like precursor solvents (N-Methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), gamma-butyrolactone (GBL)) and antisolvents (chlorobenzene (CB), dibutyl ether (DEE), diethyl ether (Et2O), etc.) is crucial to the preparation of perovskite solutions and the control of perovskite thin film crystallization. The consumption of hazardous solvents poses an imminent threat to both the health of manufacturers and the environment. Consequently, before PSCs are commercialized, the current concerns about the toxicity of solvents must be addressed. In this study, we fabricated highly efficient planar PSCs using a novel, environmentally friendly method. Initially, we employed a greener solvent engineering approach that substituted the hazardous precursor solvents with an environmentally friendly solvent called triethyl phosphate (TEP). In the following stage, we fabricated perovskite thin films without the use of an antisolvent by employing a two-step procedure. Of all the greener techniques used to fabricate PSCs, the FTO/SnO2/MAFAPbI3/spiro-OMeTAD planar device configuration yielded the highest PCE of 20.98%. Therefore, this work addresses the toxicity of the solvents used in the perovskite film fabrication procedure and provides a promising universal method for producing PSCs with high efficiency. The aforementioned environmentally friendly approach might allow for PSC fabrication on an industrial scale in the future under sustainable conditions. [ABSTRACT FROM AUTHOR]

The present study explores the intricate relationship between the geotechnical and mineralogical properties of lithomargic clays in the Uttara Kannada region of south India. Lithomargic clays, characterized by their unique composition of clay minerals and calcareous content, play a crucial role in the geotechnical behavior of soils. The study aims to provide a comprehensive understanding of the interplay between the mineralogical composition and engineering characteristics of lithomargic clays, shedding light on their suitability for various construction and infrastructure projects. The research methodology involves a systematic analysis of lithomargic clay samples collected from different locations in the Uttara Kannada region. Geotechnical investigations, including particle size distribution, Atterberg limits, unconfined compressive strength (UCS), California bearing ratio (CBR) and triaxial tests, are conducted to assess the engineering properties of the clays. Concurrently, mineralogical analyses, such as X-ray diffraction (XRD) and scanning electron microscopy (SEM), are employed to identify and quantify the clay mineral constituents within the samples. The findings of this study reveal correlations between specific mineralogical features and geotechnical behaviors of lithomargic clays. Understanding these relationships is crucial for predicting the response of these clays to different engineering applications, including slope stability, foundation design and embankment construction. The research contributes valuable insights to the scientific and engineering communities, aiding in the informed utilization of lithomargic clays in geotechnical projects in the Uttara Kannada region and beyond. The outcomes of this investigation, such as the correlation of geotechnical properties with the variation in minerals in various sample locations, enhance our understanding of the complex nature of lithomargic clays, providing a foundation for more sustainable and effective engineering practices in the geologically diverse landscapes of south India. [ABSTRACT FROM AUTHOR]

Cement-stabilization of weak and soft soils is an efficient way for ground improvement. Traditional Portland cement remains the most popular cementitious material in practice, and thus, a proper dosage design of cement-stabilized soil is of practical interest to meet the sustainable engineering requirements and to remedy environmental concerns. Based on the unconfined compression test of cement-stabilized Qiantang River silty clay, the effects of cement content, mixing moisture content, mixing-water-to-cement ratio, and curing time on the unconfined compressive strength were investigated. The results show that the mixing-water-to-cement ratio can comprehensively characterize the effects of cement content and water content on the unconfined compressive strength of the cement-stabilized clay. A prediction method for the unconfined compressive strength of cement-stabilized Qiantang River silty clay has been proposed with considerations for mixing-water-to-cement ratio and curing time. By comparing the experimental data of the present study with the existing literature data, it is found that there is a unified relationship between the unconfined compressive strength and the mixing-water-to-cement ratio of cement-stabilized Qiantang River silty clay, kaolin, Singapore marine clay, and Bangkok clay under the same curing time. The prediction method recommended by the standard may overestimate the unconfined compressive strength of cement-stabilized Qiantang River silty clay cured for 90 days. [ABSTRACT FROM AUTHOR]

The Amazon rainforest, spanning multiple countries in South America, is the world's largest equatorial expanse, housing a vast array of relatively unknown plant and animal species. Encompassing the planet's greatest flora, the Amazon offers a tremendous variety of plants from which natural lignocellulosic fibers (NLFs) can be extracted. In this century, NLFs, which have long been utilized by indigenous populations of the Amazon, have garnered interest as potential reinforcements for composites, whether polymer- or cement-based, in various technical applications such as packaging, construction, automotive products, and ballistic armor. A comparison with synthetic materials like glass, carbon, and aramid fibers, as well as other established NLFs, highlights the cost and specific property advantages of Amazon natural fibers (ANFs). Notably, the sustainable cultivation and extraction of ANFs, as alternatives to deforestation and livestock pasture, contribute to the preservation of the Amazon rainforest. This review article provides a comprehensive examination of recent studies directly related to ANF-reinforced polymer matrix composites. The specific advantages, proposed applications, and reported challenges are highlighted, shedding light on the potential of these unique natural fibers. [ABSTRACT FROM AUTHOR]

This paper focuses on the development of thin-walled panels with specific properties for applications such as water-tight structures. The authors propose the use of textile-reinforced concrete (TRC) as a composite material and highlight its advantages, which include high tensile strength, improved crack resistance, and design flexibility. The study presents a novel approach which combines TRC with reactive powder concrete (RPC) as a matrix and a lightweight aggregate. RPC, known for its brittle behaviour, is reinforced with glass fibres and a textile fabric to increase its flexural strength. The research includes a comprehensive analysis of the physical and mechanical properties of both the unreinforced RPC matrix and the TRC composite. In particular, the lightweight aggregate RPC matrix has a porosity of 41%, and its mechanical properties, such as flexural and compressive strength, are discussed. The TRC composites, produced in thicknesses ranging from 1 mm to 4 mm, are subjected to flexural tests to evaluate their behaviour under load. The thicker elements show typical damage phases, while the thinner elements show greater flexibility and elasticity. SEM observations confirm good adhesion between the glass fibres and the RPC matrix. Water permeability tests show that the TRC composite, despite its highly porous structure, achieves a water permeability two orders of magnitude higher than that of a reference material, highlighting the roles of both the porous aggregate and the matrix hydration. The paper concludes with a proof of concept—a canoe called the PKanoe, which is constructed from the developed TRC composite. The design of the canoe is supported by numerical analysis to ensure its optimal shape and structural integrity under load. The research contributes to the exploration of innovative materials for sustainable civil engineering applications and addresses both structural and environmental considerations. [ABSTRACT FROM AUTHOR]

Due to a growing number of environmental issues, including global warming, water scarcity, and fossil fuel depletion, the topic of modern materials in energy is becoming crucial for our civilization. The technological advancements that have been observed bring many innovations that significantly impact how energy can be generated, stored, and distributed. Moreover, new opportunities have emerged in energy and materials engineering due to the increasing computational capability of current data processing systems. Methods that are highly demanding, time-consuming, and difficult to apply may now be considered when developing complete and sophisticated models in many areas of science and technology. Combining computational methods and AI algorithms allows for multi-threaded analyses solving advanced and interdisciplinary problems. Therefore, knowledge and experience in this subject, as well as the investigation of new, more efficient, and environmentally friendly solutions, currently represent one of the main directions of scientific research. The Special Issue "Advances in Materials: Modelling Challenges and Technological Progress for Green Engineering and Sustainable Development" aims to bring together research on material advances, focusing on modelling challenges and technological progress (mainly for green engineering and sustainable development). Original research studies, review articles, and short communications are welcome, especially those focusing on (but not limited to) artificial intelligence, other computational methods, and state-of-the-art technological concepts related to the listed keywords within energy and materials engineering. [ABSTRACT FROM AUTHOR]

In the pursuance of engineering excellence and sustainable practices, the optimization of material selection processes plays a crucial role. Using Fermatean fuzzy aggregation Operators (AOs), this study introduces an innovative method for improving material selection procedures. Combining the advantages of Fermatean fuzzy set (FrFS) and AOs, the proposed method enables a comprehensive evaluation of materials based on multiple criteria. The authors propose two operators: the "Fermatean fuzzy hybrid weighted arithmetic geometric aggregation (FrFHWAGA) operator" and the "Fermatean fuzzy hybrid ordered weighted arithmetic geometric aggregation (FrFHOWAGA) operator". This method facilitates informed decision making in a number of industries by taking into account factors such as cost, durability, environmental impact, and availability. This research enables engineers, designers, and decision makers to optimize material selection, resulting in more efficient, cost-effective, and sustainable solutions across multiple domains. [ABSTRACT FROM AUTHOR]

Alkali-activated engineered composites (AAECs) are cement-free composites developed using alkali activation technology, which exhibit strain hardening and multiple micro-cracking like conventional engineered cementitious composites (ECCs). Such AAECs are developed in this study by incorporating 2% v/v polyvinyl alcohol (PVA) fibers into alkali-activated mortars (AAMs) produced using binary/ternary combinations of fly ash class C (FA-C), fly ash class F (FA-F), and ground-granulated blast furnace slag (GGBFS) with powder-form alkaline reagents and silica sand through a one-part mixing method under ambient curing conditions. The mechanical and microstructural characteristics of eight AAECs are investigated to characterize their strain-hardening performance based on existing (stress and energy indices) and newly developed tensile/flexural ductility indices. The binary (FA-C + GGBFS) AAECs obtained higher compressive strengths (between 48 MPa and 52 MPa) and ultrasonic pulse velocities (between 3358 m/s and 3947 m/s) than their ternary (FA-C + FA-F + GGBFS) counterparts. The ternary AAECs obtained a higher fracture energy than their binary counterparts. The AAECs incorporating reagent 2 (Ca(OH)2: Na2SO4 = 2.5:1) obtained a greater fracture energy and compressive strengths than their counterparts with reagent 1 (Ca(OH)2: Na2SiO3.5H2O = 1:2.5), due to additional C-S-H gel formation, which increased their energy absorption for crack propagation through superior multiple-cracking behavior. A lower fracture and crack-tip toughness facilitated the development of enhanced flexural strength characteristics with higher flexural strengths (ranging from 5.3 MPa to 11.3 MPa) and a higher energy ductility of the binary AAMs compared to their ternary counterparts. The tensile stress relaxation process was relatively gradual in the binary AAECs, owing to the formation of a more uniform combination of reaction products (C-S-H/C-A-S-H) rather than a blend of amorphous (N-C-A-S-H/N-A-S-H) and crystalline (C-A-S-H/C-S-H) binding phases in the case of the ternary AAECs. All the AAECs demonstrated tensile strain-hardening characteristics at 28 days, with significant improvements from 28% to 100% in the maximum bridging stresses for mixes incorporating 40% to 45% GGBFS at 365 days. This study confirmed the viability of producing green cement-free strain-hardening alkali-activated composites with powder-form reagents, with satisfactory mechanical characteristics under ambient conditions. [ABSTRACT FROM AUTHOR]

The green model microalga Chlamydomonas reinhardtii recently emerged as a sustainable production chassis for the efficient biosynthesis of recombinant proteins and high-value metabolites. Its capacity for scalable, rapid and light-driven growth in minimal salt solutions, its simplicity for genetic manipulation and its "Generally Recognized As Safe" (GRAS) status are key features for its application in industrial biotechnology. Although nuclear transformation has typically resulted in limited transgene expression levels, recent developments now allow the design of powerful and innovative bioproduction concepts. In this review, we summarize the main obstacles to genetic engineering in C. reinhardtii and describe all essential aspects in sequence adaption and vector design to enable sufficient transgene expression from the nuclear genome. Several biotechnological examples of successful engineering serve as blueprints for the future establishment of C. reinhardtii as a green cell factory. [ABSTRACT FROM AUTHOR]

Green chemistry and engineering encourage the usage of renewable sources, in replacement fossil fuels. The sector of bio-based products is one of the most predominant examples of such replacements in different fields. However, the impact of biomasses usage is far from being negligible or net zero. A life cycle perspective is required in order to assess all the different environmental impacts related to biomass exploitation and usage, in particular when dedicated sources are used. This study points out the importance of including the results of a Life Cycle Assessment (LCA) early in the design of new bio-based products, to identify the stage of the value chain with the greatest hotspots and set proper eco-design strategies. At the same time, the use of the LCA results may support purchasing activities through comparing products with different burdens. In this manuscript, a focus on land compartment is carried out, given its relevance to the cultivation phase. Five analysis methods are selected for further description. Three are classified as multi-impact approach methodologies (ReCiPe 2016, IMPACT World + and EF 3.0) since they are able to translate mass and energy balances into several impact categories at the same time, not only those on land comparts which are also included. In addition, the LANCA® model and the True pricing method for agri-food products are discussed, underlining the importance of their usage when a detailed review of the impact on soil is necessary (e.g., during an environmental impact assessment). They are compared in this paper, underlining the main differences and potential fields of application. [ABSTRACT FROM AUTHOR]

Multi-criteria decision-making (MCDM) methods have gained increased attention in sustainable engineering, where complex decision-making problems require consideration of multiple criteria and stakeholder perspectives. This review paper provides a comprehensive overview of the different MCDM methods, their applications in sustainable engineering, and their strengths and weaknesses. The paper discusses the concept of sustainable engineering, its principles, and the different areas where MCDM methods have been applied, including energy, manufacturing, transportation, and environmental engineering. Case studies of real-world applications are presented and analyzed, highlighting the main findings and implications for engineering practice. Finally, the challenges and limitations of MCDM methods in sustainable engineering are discussed, and future research directions are proposed. This review contributes to the understanding of the role of MCDM methods in sustainable engineering and provides guidance for researchers and practitioners. [ABSTRACT FROM AUTHOR]

The additive manufacturing of natural fibre-reinforced polymers is a pivotal method in developing sustainable engineering solutions. Using the fused filament fabrication method, the current study investigates the additive manufacturing of hemp-reinforced polybutylene succinate (PBS) alongside its mechanical characterization. Two types of hemp reinforcement are considered: short fibres (max. length smaller than 2 mm) and long fibres (max. length smaller than 10 mm), which are compared against non-reinforced (pure) PBS. A detailed analysis is performed regarding the determination of suitable 3D printing parameters (overlap, temperature, nozzle diameter). In a comprehensive experimental study, additionally to general analyses regarding the influence of hemp reinforcement on the mechanical behaviour, the effect of printing parameters is determined and discussed. Introducing an overlap in the additive manufacturing of the specimens results in improved mechanical performance. The study highlights that the Young's modulus of PBS can be improved by 63% by introducing hemp fibres in conjunction with overlap. In contrast, hemp fibre reinforcement reduces the tensile strength of PBS, while this effect is less pronounced considering overlap in the additive manufacturing process. [ABSTRACT FROM AUTHOR]

The stress–strain constitutive model under uniaxial compression is a basic element and important characterization method for determining physical and mechanical properties in cement-based materials research. In this study, a stress–strain constitutive model under uniaxial compression was established, which was based on a new nano-stabilized soil (NSS) through typical mechanical tests and constitutive relationship research. The results indicate that the unconfined compressive strength (UCS) of the nano-stabilized soil was enhanced with the increase in curing period and nano-stabilizer dosage, and that the strength growth rate reaches the maximum at a 12% dosage in the tested samples. The UCS of NSS under a 12% dosage is about 10~15% higher than that of ordinary stabilized soil (SS) without nano doping, and 25~40% higher compared with grade 42.5 cement-soil. The established constitutive model could accurately describe the linear-elastic and elastic-plastic deformation characteristics of NSS under uniaxial compression, which will be conducive to revealing the curve variation law of the stress–strain process. The research results could provide scientific support for the theoretical innovation and engineering application of green environmental protection materials. [ABSTRACT FROM AUTHOR]

One of the key challenges in using fossil fuels is the environmental impacts of these energy sources, and to reduce these destructive effects, the use of renewable energy sources (biofuels) is necessary. One of the important biofuels is biodiesel, which can be produced from cottonseed. To properly manage the chain dealing with biodiesel production from the cottonseed chain (from farm to manufactory), environmental hotspots must be pinpointed. In the present study, it was attempted to examine the environmental impacts of the biodiesel production cycle from cottonseed (agronomic stages, ginning, oiling, and biodiesel production). The data obtained in all three stages were analyzed by the Impact 2002+ method in the SimaPro software. The highest contribution to creating environmental indicators at the agricultural stage was related to the use of nitrogen fertilizers, direct emission from the farm and fossil fuels, the ginning and oiling stage involving the use of diesel fuel and sulfuric acid, and the production of biodiesel in the manufactory involving the use of methanol and electricity. The potential environmental impacts of a functional unit of 1 kg of biodiesel include: human health, 9.05–10−6 (DAYLY); ecosystem quality, 1.369 (PDF*m2*year); climate changes, (kg CO2 eq.) 17.247; and resources (MJ primary), 89.116. Results showed that agriculture has more significant participation in the environmental impact than other sections (ginning and oiling and biodiesel production), especially due to the application of fertilizers and fuel. Surveying the environmental indicators of the results showed that at the agricultural stage, the human health indicator is 10.43, 1.21, and 5.32 times higher than the ecosystem quality, climate change, and resource indicators, respectively; at the ginning and oiling stages, it is 2.35, 31.68, and 2.09 times higher, respectively; and at the stage of biodiesel production in the manufactory, it is 16.41, 1.96, and 0.99 times higher, respectively, in terms of the destructive effects. The overall results showed that the hotspot points in the present study can be largely modified by reducing the consumption of nitrogen fertilizers, using new equipment and machinery, ginning and oiling, and using fewer methanol ratios than oil. [ABSTRACT FROM AUTHOR]

Highlights: The article reviewed plasma research on natural fiber functionalization and sustainable polymeric derivatives in the last two decades. The article highlighted various plasma processes: functionalization, ablation, ion implantation, grafting, and polymerization, with special emphasis on natural fiber materials. The review article focused on plasma-modified sustainable materials' application in heavy metal remediation, water purification, biomedical applications, packaging materials, and sensor applications. Plasma processing employed fortuitously to alter the natural fibers and sustainable polymeric derivatives for potential applications reducing the environmentally hazardous chemicals. The revamped surface properties such as hydrophilicity, adhesion, and surface energy of the materials by dint of plasma processing ensures wide applicability of the sustainable polymeric materials. Recently, natural as well as synthetic polymers have been receiving significant attention as candidates to replace non-renewable materials. With the exponential developments in the world each day, the collateral damage to the environment is incessant. Increased demands for reducing pollution and energy consumption are the driving force behind the research related to surface-modified natural fibers (NFs), polymers, and various derivatives of them such as natural-fiber-reinforced polymer composites. Natural fibers have received special attention for industrial applications due to their favorable characteristics, such as low cost, abundance, light weight, and biodegradable nature. Even though NFs offer many potential applications, they still face some challenges in terms of durability, strength, and processing. Many of these have been addressed by various surface modification methodologies and compositing with polymers. Among different surface treatment strategies, low-temperature plasma (LTP) surface treatment has recently received special attention for tailoring surface properties of different materials, including NFs and synthetic polymers, without affecting any of the bulk properties of these materials. Hence, it is very important to get an overview of the latest developments in this field. The present article attempts to give an overview of different materials such as NFs, synthetic polymers, and composites. Special attention was placed on the low-temperature plasma-based surface engineering of these materials for diverse applications, which include but are not limited to environmental remediation, packaging, biomedical devices, and sensor development. [ABSTRACT FROM AUTHOR]

One of the most effective cost reduction and green engineering projects is to introduce organic compounds to electrode materials instead of expensive inorganic-based materials. In this work, derivatives of perylene diimide substituted with amino acids (PDI_AAs) showed the characteristics of redox-active organic compounds and were, therefore, used as cathode materials of lithium-ion batteries (LIBs). Among the as-synthesized PDI_AAs, the L-alanine-substituted PDI (PDI_A) showed the most improved cycling performances of 86 mAhg−1 over 150 cycles with retention of 95% at 50 mAg−1. Furthermore, at a high current density of 500 mAg−1, PDI_A exhibited a long-term cycling performance of 47 mAhg−1 (retention to 98%) over 5000 cycles. In addition, ex situ attenuated total reflection Fourier-transform infrared spectroscopy (ATR FT-IR) analysis of electrodes at various charging states showed the mechanism of the charge-discharge process of PDI_A. [ABSTRACT FROM AUTHOR]

With the active development of offshore wind power worldwide, the development of a green and ecofriendly grouting material (GEGM) has garnered global attention. Such a material must also be developed in Taiwan. Therefore, in this study, a series of environmentally friendly recycled materials were mixed in different proportions to develop a GEGM which can be implemented in the future construction of offshore wind turbines. To evaluate the mechanical properties of the GEGM, low water-to-binder (W/B) ratios (i.e., 0.21, 0.27, and 0.35) were used; cement was replaced with fixed amounts (20%) of ground granulated blast-furnace slag and fly ash; 2%, 2.5%, and 3% superplasticizers (SPs) were added; and two levels of sand content (60% and 70%) were used. The setting time of the GEGM was used to evaluate its workability; its compressive strength and flexural strength were used to evaluate its mechanical properties; and its sulfate resistance, length changes, and four-terminal resistance were used to evaluate its durability. The relationship between the durability and drying shrinkage of the GEGM was subsequently evaluated, and the ratio of final to initial setting times (F/I value) was calculated to determine the effects of the amount of SP added on workability. The highest F/I value (7.7) was achieved when 2 wt.% modified lignin sulfonate (MLS) was added because of the high viscosity of MLS, which compromised the workability of the concrete. The optimal compressive strength (83.62 MPa) was achieved when a W/B ratio of 0.21 was used, when the sand content was 70%, and when a 2% polycarboxylate superplasticizer (PCE) was added, whereas the optimal flexural strength (20.86 MPa) was achieved when 2.5% PCE was added. According to the nondestructive test results and the R2 value (>0.7) obtained from regression analyses of mechanical properties, the study results are reliable and may serve as a reference for future construction projects. [ABSTRACT FROM AUTHOR]

Nowadays, heterogeneous photocatalysis for water treatment and hydrogen production are topics gaining interest for scientists and developers from different areas, such as environmental technology and material science. Most of the efforts and resources are devoted to the development of new photocatalyst materials, while the modeling and development of reaction systems allowing for upscaling the process to pilot or industrial scale are scarce. In this work, we present what is known on the upscaling of heterogeneous photocatalysis to purify water and to produce green H2. The types of reactors successfully used in water treatment plants are presented as study cases. The challenges of upscaling the photocatalysis process to produce green H2 are explored from the perspectives of (a) the adaptation of photoreactors, (b) the competitiveness of the process, and (c) safety. Throughout the text, Green Chemistry and Engineering Principles are described and discussed on how they are currently being applied to the heterogeneous photocatalysis process along with the challenges that are ahead. Lastly, the role of automation and high-throughput methods in the upscaling following the Green Principles is discussed. [ABSTRACT FROM AUTHOR]

Insulating polymeric foams have an important role to play in increasing energy efficiency and therefore contributing to combating climate change. Their development in recent years has been driven towards the reduction of thermal conductivity and achievement of the required mechanical properties as main targets towards sustainability. This perception of sustainability has overseen the choice of raw materials, which are often toxic, or has placed research efforts on optimizing one constituent while the other necessary reactants remain hazardous. The transition to the circular economy requires a holistic understanding of sustainability and a shift in design methodology and the resulting research focus. This paper identifies research needs and possible strategies for polymeric foam development compatible with Circular Product Design and Green Engineering, based on an extensive literature review. Identified research needs include material characterization of a broader spectrum of polymer melt–gas solutions, ageing behavior, tailoring of the polymer chains, detailed understanding and modeling of the effects of shear on cell nucleation, and the upscaling of processing tools allowing for high and defined pressure drop rates. [ABSTRACT FROM AUTHOR]

Applications of ultra-low-pressure filtration systems are increasing as they offer enhanced sustainability due to lower energy input, almost no use of chemicals, and minimum operational expenditure. In many cases, they operate as a decentralized system using a gravity-driven membrane (GDM) filtration process. These applications are relatively new; hence, the fundamental knowledge of the process is still limited. In this study, we investigated the phenomenon of polymeric membrane compaction under an ultra-low-pressure system. The compaction phenomenon is well-recognized in the traditional pressure-driven system operating at high transmembrane pressures (ΔPs > 200 kPa), but it is less documented in ultra-low-pressure systems (ΔP < 10 kPa). A simple GDM filtration setup operated under a constant-pressure system was employed to investigate the compaction phenomena in a polymeric hollow fiber membrane for clean water filtration. Firstly, a short-term pressure stepping test was performed to investigate the occurrence of instantaneous compaction in the ΔP range of 1–10 kPa. The slow compaction was later investigated. Finally, the compaction dynamic was assessed under alternating high and low ΔP and relaxation in between the filtrations. The findings demonstrated the prominence of membrane compaction, as shown by the decreasing trend in clean water permeability at higher ΔPs (i.e., 3240 and 2401 L m−2 h−1 bar−1 at ΔPs of 1 and 10 kPa, respectively). We also found that the intrinsic permeability of the applied polymeric membrane was significantly higher than the apparent one (4351 vs. 2401 L m−2 h−1 bar−1), demonstrating >50% loss due to compaction. The compaction was mainly instantaneous, which occurred when the ΔP was changed, whereas only minor changes in permeability occurred over time when operating at a constant ΔP. The compaction was highly reversible and could be restored (i.e., decompaction) through relaxation by temporarily stopping the filtration. A small fraction of irreversible compaction could be detected by operating alternating filtrations under ΔPs of 1 and 10 kPa. The overall findings are essential to support emerging GDM filtration applications, in which membrane compaction has been ignored and confounded with membrane fouling. The role of compaction is more prominent for high-flux GDM filtration systems treating less-fouling-prone feed (i.e., rainwater, river water) and involving membrane cleaning (i.e., relaxation) in which both reversible and irreversible compaction occurred simultaneously. [ABSTRACT FROM AUTHOR]

The exponential increase of plastic production produces 100 million tonnes of waste plastics annually which could be converted into hydrocarbon fuels in a thermal cracking process called pyrolysis. In this research work, a direct current (DC) thermal plasma circuit is designed and used for conversion of low density polyethylene (LDPE) into diesel oil in a laboratory scale pyrolysis reactor. The experimental setup uses a 270 W DC thermal plasma at operating temperatures in the range of 625 °C to 860 °C for a low density polyethylene (LDPE) pyrolysis reaction at pressure = 􀀀0.95, temperature = 550 °C with τ = 30 min at a constant heating rate of 7.8 °C/min. The experimental setup consists of a vacuum pump, closed system vessel, direct current (DC) plasma circuit, and a k-type thermocouple placed a few millimeters from the reactant sample. The hydrocarbon products are condensed to diesel oil and analyzed using flame ionization detector (FID) gas chromatography. The analysis shows 87.5% diesel oil, 1,4-dichlorobenzene (Surr), benzene, ethylbenzene and traces of toluene and xylene. The direct current (DC) thermal plasma achieves 56.9 wt. % of diesel range oil (DRO), 37.8 wt. % gaseous products and minimal tar production. The direct current (DC) thermal plasma shows reliability, better temperature control, and high thermal performance as well as the ability to work for long operation periods. [ABSTRACT FROM AUTHOR]

Italy, like every country member of the European Union (EU), will have to achieve the objectives required by the Energy Roadmap 2050. The purpose of the study was to evaluate the environmental impacts of residue recovery arising from the management of public and private green feedstocks, activity of the cooperative "Green City" in the Bologna district, and usage in a centralized heating system to produce thermal energy for public buildings. Results, obtained using the ReCipe impact assessment method, are compared with scores achieved by a traditional methane boiler. The study shows some advantages of the biomass-based system in terms of greenhouse gases (GHGs) emissions and consumption of non-renewable fuels, which affect climate change (-41%) and fossil resources depletion (-40%), compared to the use of natural gas (NG). Moreover, scores from network analysis denote the great contribution of feedstock transportation (98% of the cumulative impact). The main reason is attributable to all requirements to cover distances, in particular due to stages involved in the fuel supply chains. Therefore, it is clear that greater environmental benefits could be achieved by reducing supply transport distances or using more sustainable engines. [ABSTRACT FROM AUTHOR]

New product development review article aims to consolidate the principles and current literature on design for sustainability to seek the field's future direction. In this point of view, the design for sustainability methods can be established under the idea of sustainability in dimensions of ecology, economy and social pillars. Design for sustainability concept is implemented in concurrent engineering, including concept, embodiment and detail design processes. Integrating sustainability in engineering designs is crucial to producing greener products, system innovation, and services aligned with current market demand. Currently, many concurrent engineering studies related to natural fibre-reinforced polymer composites associated with sustainability enhance the application of design for sustainability techniques by professional designers. However, the current literature is scarce in bridging the design for sustainability concept with concurrent engineering during the design development stage, and these areas should be further developed. Several other future research directions, such as the need for aligning with principles and applications, along with exploring the relationships between the design for sustainability techniques and views of sustainability, are presented in this review paper. [ABSTRACT FROM AUTHOR]

Drug delivery systems (DDS) often comprise biopharmaceuticals in aqueous form, making them susceptible to physical and chemical degradation, and therefore requiring low temperature storage in cold supply and distribution chains. Freeze-drying, spray-drying, and spray-freeze-drying are some of the techniques used to convert biopharmaceuticals-loaded DDS from aqueous to solid dosage forms. However, the risk exists that shear and heat stress during processing may provoke DDS damage and efficacy loss. Supercritical fluids (SCF), specifically, supercritical carbon dioxide (scCO2), is a sustainable alternative to common techniques. Due to its moderately critical and tunable properties and thermodynamic behavior, scCO2 has aroused scientific and industrial interest. Therefore, this article reviews scCO2-based techniques used over the year in the production of solid biopharmaceutical dosage forms. Looking particularly at the use of scCO2 in each of its potential roles—as a solvent, co-solvent, anti-solvent, or co-solute. It ends with a comparison between the compound's stability using supercritical CO2-assisted atomization/spray-drying and conventional drying. [ABSTRACT FROM AUTHOR]

Cellulose materials and products are frequently affected by environmental factors such as light, temperature, and humidity. Simulated UV irradiation, heat, and moisture exposure were comprehensively used to characterize changes in cellulose nanopaper (NP) tensile properties. For the preparation of NP, high-purity cellulose from old, unused filter paper waste was used. Lignin and xylan were used as sustainable green interface engineering modifiers for NP due to their structural compatibility, low price, nontoxic nature, and abundance as a by-product of biomass processing, as well as their ability to protect cellulose fibers from UV irradiation. Nanofibrillated cellulose (NFC) suspension was obtained by microfluidizing cellulose suspension, and NP was produced by casting films from water suspensions. The use of filler from 1 to 30 wt% significantly altered NP properties. All nanopapers were tested for their sensitivity to water humidity, which reduced mechanical properties from 10 to 40% depending on the saturation level. Xylan addition showed a significant increase in the specific elastic modulus and specific strength by 1.4- and 2.8-fold, respectively. Xylan-containing NPs had remarkable resistance to UV irradiation, retaining 50 to 90% of their initial properties. Lignin-modified NPs resulted in a decreased mechanical performance due to the particle structure of the filler and the agglomeration process, but it was compensated by good property retention and enhanced elongation. The UV oxidation process of the NP interface was studied with UV-Vis and FTIR spectroscopy, which showed that the degradation of lignin and xylan preserves a cellulose fiber structure. Scanning electron microscopy images revealed the structural formation of the interface and supplemented understanding of UV aging impact on the surface and penetration depth in the cross-section. The ability to overcome premature aging in environmental factors can significantly benefit the wide adaption of NP in food packaging and functional applications. [ABSTRACT FROM AUTHOR]

The push for environmental sustainability in the civil engineering industry has resulted in an increased interest in the use of recycled construction materials, with one example being the use of waste plastic for the modification of bituminous binder in asphalt mixtures. Existing research has associated waste plastics with various binder and asphalt mixture performance enhancing properties. However, there is a lack of research on the age-related durability of waste plastic-modified roads. This research compared the effect of commercially available waste plastic binder modifiers on the ageing phenomenon of bituminous binders and asphalt mixtures, to the effect of conventional polymers SBS and EVA, through artificial bituminous binder and asphalt mixture ageing performed in a laboratory. The addition of polymers (both waste and virgin) resulted in an increase in binder stiffness after short-term ageing as the polymer content increased. The effect of the waste plastic on ageing was comparable to the effects associated with the conventional polymers, and it was concluded that the waste plastic binder modified products should be considered sustainable alternatives to standard polymers for bituminous binder and asphalt mixture modification. [ABSTRACT FROM AUTHOR]

Ecological engineering is a widely used strategy to address environmental degradation and enhance human well-being. A quantitative assessment of the impacts of ecological engineering on ecosystem services (ESs) is a prerequisite for designing inclusive and sustainable engineering programs. In order to strengthen national ecological security, the Chinese government has implemented the world's largest ecological project since 1999, the Grain for Green Program (GFGP). We used a professional model to evaluate the key ESs in Lvliang City. Scenario analysis was used to quantify the contribution of the GFGP to changes in ESs and the impacts of trade-offs/synergy. We used spatial regression to identify the main drivers of ES trade-offs. We found that: (1) From 2000 to 2018, the contribution rates of the GFGP to changes in carbon storage (CS), habitat quality (HQ), water yield (WY), and soil conservation (SC) were 140.92%, 155.59%, −454.48%, and 92.96%, respectively. GFGP compensated for the negative impacts of external environmental pressure on CS and HQ, and significantly improved CS, HQ, and SC, but at the expense of WY. (2) The GFGP promotes the synergistic development of CS, HQ, and SC, and also intensifies the trade-off relationships between WY and CS, WY and HQ, and WY and SC. (3) Land use change and urbanization are significantly positively correlated with the WY–CS, WY–HQ, and WY–SC trade-offs, while increases in NDVI helped alleviate these trade-offs. (4) Geographically weighted regression explained 90.8%, 94.2%, and 88.2% of the WY–CS, WY–HQ, and WY–SC trade-offs, respectively. We suggest that the ESs' benefits from the GFGP can be maximized by controlling the intensity of land use change, optimizing the development of urbanization, and improving the effectiveness of afforestation. This general method of quantifying the impact of ecological engineering on ESs can act as a reference for future ecological restoration plans and decision-making in China and across the world. [ABSTRACT FROM AUTHOR]

Polymers are considered to be good hosting matrices for composite materials because they can easily be tailored to yield a variety of bulk physical properties. Moreover, organic polymers generally have long-term stability and good processability. Inorganic nanoparticles possess outstanding optical, catalytic, electronic and magnetic properties, which are significantly different their bulk states. By combining the attractive functionalities of both components, nanocomposites derived from organic polymers and inorganic nanoparticles are expected to display synergistically improved properties. The potential applications of the resultant nanocomposites are various, e.g. automotive, aerospace, opto-electronics, etc. Here, we review recent progress in polymer-based inorganic nanoparticle composites. [ABSTRACT FROM AUTHOR]

During biogas combustion, siloxanes form deposits of SiO2 on engine components, thus shortening the lifespan of the installation. Therefore, the development of new methods for the purification of biogas is receiving increasing attention. One of the most effective methods is physical absorption with the use of appropriate solvents. According to the principles of green engineering, solvents should be biodegradable, non-toxic, and have a high absorption capacity. Deep eutectic solvents (DES) possess such characteristics. In the literature, due to the very large number of DES combinations, conductor-like screening models for real solvents (COSMO-RS), based on the comparison of siloxane activity coefficient of 90 DESs of various types, were studied. DESs, which have the highest affinity to siloxanes, were synthesized. The most important physicochemical properties of DESs were carefully studied. In order to explain of the mechanism of DES formation, and the interaction between DES and siloxanes, the theoretical studies based on σ-profiles, and experimental studies including the 1H NMR, 13C NMR, and FT-IR spectra, were applied. The obtained results indicated that the new DESs, which were composed of carvone and carboxylic acids, were characterized by the highest affinity to siloxanes. It was shown that the hydrogen bonds between the active ketone group (=O) and the carboxyl group (-COOH) determined the formation of stable DESs with a melting point much lower than those of the individual components. On the other hand, non-bonded interactions mainly determined the effective capture of siloxanes with DES. [ABSTRACT FROM AUTHOR]

Several agro-waste materials have been utilized for sustainable engineering and environmental application over the past decades, showing different degrees of effectiveness. However, information concerning the wider use of palm oil clinker (POC) and its performance is still lacking. Therefore, as a solid waste byproduct produced in one of the oil palm processing stages, generating a huge quantity of waste mostly dumped into the landfill, the waste-to-resource potential of POC should be thoroughly discussed in a review. Thus, this paper provides a systematic review of the current research articles on the several advances made from 2005 to 2021 regarding palm oil clinker physical properties and performances, with a particular emphasis on their commitments to cost savings during environmental and engineering applications. The review begins by identifying the potential of POC application in conventional and geopolymer structural elements such as beams, slabs, and columns made of concrete, mortar, or paste for coarse aggregates, sand, and cement replacement. Aspects such as performance of POC in wastewater treatment processes, fine aggregate and cement replacement in asphaltic and bituminous mixtures during highway construction, a bio-filler in coatings for steel manufacturing processes, and a catalyst during energy generation are also discussed. This review further describes the effectiveness of POC in soil stabilization and the effect of POC pretreatment for performance enhancement. The present review can inspire researchers to find research gaps that will aid the sustainable use of agroindustry wastes. The fundamental knowledge contained in this review can also serve as a wake-up call for researchers that will motivate them to explore the high potential of utilizing POC for greater environmental benefits associated with less cost when compared with conventional materials. [ABSTRACT FROM AUTHOR]

The development of polymers photopolymerized from renewable resources are extensively growing as fulfills green chemistry and green engineering principles. With the rapid growth of consumerism, research on innovative starting materials for the preparation of polymers may help to reduce the negative impact of petroleum-based plastic materials on the global ecosystem and on animal and human health. Therefore, bio-based crosslinked polymers have been synthesized from functionalized soybean oil and squalene by thiol–ene ultra-violet (UV) curing. First, thiol–ene UV curing of squalene was performed to introduce thiol functional groups. Then, hexathiolated squalene was used as a crosslinker in click UV curing of acrylated epoxidized soybean oil. Two photoinitiators, 2-hydroxy-2-methylpropiophenone and ethylphenyl (2,4,6-trimethylbenzoyl) phosphinate, were tested in different quantities. Rheological properties of the resins were monitored by real-time photorheometry. The characterization of obtained polymers was performed by differential scanning calorimetry, thermogravimetry, and Shore A hardness measurements. Polymers possessed higher storage modulus, thermal characteristics, Shore A hardness, and lower swelling value when ethylphenyl (2,4,6-trimethylbenzoyl) phosphinate was used as photoinitiator. [ABSTRACT FROM AUTHOR]

Surveys of managed honey bee colony losses worldwide have become fundamental for engineering a sustainable and systematic approach to protect honey bees. Though China is a member of the world's apiculture superpowers, the investigation of honey bee colony losses from Chinese government was not formally launched until recently. In this study, we investigated the colony winter losses of the western honey bee (Apis mellifera) of four consecutive years in 2013–2017 from 19 provinces in China, with a total of 2387 responding Chinese beekeepers (195 hobby beekeepers, 1789 side-line beekeepers, 403 commercial beekeepers) providing the records of overwintering mortality of honey bee colonies. The calculated colony losses were 8.7%, a relatively low mortality below the world average. There still exist considerable variations in total losses among provinces (ranging from 0.9% to 22.0%), years (ranging from 8.1% to 10.6%) and scales of apiaries (ranging from 7.5% to 10.0%). Furthermore, we deeply analyzed and estimated the effects of potential risk factors on the colonies' winter losses, and speculated that the queen problems, the operation sizes and proportion of new queens are leading causes of the high honey bee colony mortality in China. More research and advanced technical methods are still required for correlation analysis and verification in future surveys of managed honey bee colony winter losses. [ABSTRACT FROM AUTHOR]

This study addresses the thermal and energy performance assessment of a Building Integrated Photovoltaic Thermal (BIPVT) system installed on the façade of a test room in Solar XXI, a Net Zero Energy Building (NZEB) located in Lisbon, Portugal. A numerical analysis using the dynamic simulation tool EnergyPlus was carried out for assessing the performance of the test room with the BIPVT integrated on its façade through a parametric analysis of 14 scenarios in two conditions: a) receiving direct solar gains on the glazing surface and b) avoiding direct solar gains on the glazing surface. Additionally, a computational fluid dynamics (CFD) analysis of the BIPVT system was performed using ANSYS Fluent. The findings of this work demonstrate that the BIPVT has a good potential to improve the sustainability of the building by reducing the nominal energy needs to achieve thermal comfort, reducing up to 48% the total energy needs for heating and cooling compared to the base case. The operation mode must be adjusted to the other strategies already implemented in the room (e.g., the presence of windows and blinds to control direct solar gains), and the automatic operation mode has proven to have a better performance in the scope of this work. [ABSTRACT FROM AUTHOR]

The success of any activity and process depends fundamentally on the possibility of balancing (symmetry) needs and their satisfaction. That is, the ability to properly define a set of success indicators. The application of the developed new multi-criteria decision-making (MCDM) methods can be eliminated or decreased by decision-makers' subjectivity, which leads to consistency or symmetry in the weight values of the criteria. In this Special Issue, 40 research papers and one review study co-authored by 137 researchers from 23 different countries explore aspects of multi-criteria modeling and optimization in crisp or uncertain environments. The papers proposing new approaches and elaborate case studies in the following areas of applications: MCDM optimization in sustainable engineering, environmental sustainability in engineering processes, sustainable multi-criteria production and logistics processes planning, integrated approach for modeling processes in engineering, new trends in the multi-criteria evaluation of sustainable processes, multi-criteria decision-making in strategic management based on sustainable criteria. [ABSTRACT FROM AUTHOR]

Sensor networks are essential for the development of the Internet of Things and the smart city. A general sensor, especially a mobile sensor, has to be driven by a power unit. When considering the high mobility, wide distribution and wireless operation of the sensors, their sustainable operation remains a critical challenge owing to the limited lifetime of an energy storage unit. In 2006, Wang proposed the concept of self-powered sensors/system, which harvests ambient energy to continuously drive a sensor without the use of an external power source. Based on the piezoelectric nanogenerator (PENG) and triboelectric nanogenerator (TENG), extensive studies have focused on self-powered sensors. TENG and PENG, as effective mechanical-to-electricity energy conversion technologies, have been used not only as power sources but also as active sensing devices in many application fields, including physical sensors, wearable devices, biomedical and health care, human–machine interface, chemical and environmental monitoring, smart traffic, smart cities, robotics, and fiber and fabric sensors. In this review, we systematically summarize the progress made by TENG and PENG in those application fields. A perspective will be given about the future of self-powered sensors. [ABSTRACT FROM AUTHOR]

The Special Issue of the Manufacturing Engineering Society 2019 (SIMES-2019) has been launched as a joint issue of the journals "Materials" and "Applied Sciences". The 29 contributions published in this Special Issue of Materials present cutting-edge advances in the field of manufacturing engineering focusing on additive manufacturing and 3D printing, advances and innovations in manufacturing processes, sustainable and green manufacturing, manufacturing of new materials, metrology and quality in manufacturing, industry 4.0, design, modeling, and simulation in manufacturing engineering and manufacturing engineering and society. Among them, these contributions highlight that the topic "additive manufacturing and 3D printing" has collected a large number of contributions in this journal because its huge potential has attracted the attention of numerous researchers over the last years. [ABSTRACT FROM AUTHOR]

This paper describes the results of recent research carried out with the UK energy sector to assess low-carbon related skills gaps and training requirements at the masters-level. Via iterative engagement across the industry, the characteristics of the market for new 'needs-driven' industry-focussed masters-level training offerings were defined. The results, taken together with the outcomes of a gap analysis of existing masters-level training, support the creation of a new framework for masters-level energy education that will more effectively meet the growing unmet need for such skills in the UK and beyond. The outcomes of the research indicate that flexibility in both delivery mode and curriculum content across both technical and non-technical disciplines is essential, along with improved supplier agility to rapidly develop new courses in evolving engineering specialisations. Without responding effectively to such demands from industry, we conclude that the advanced skills needed across the highly dynamic UK and global energy engineering sector will be in increasingly short supply. [ABSTRACT FROM AUTHOR]

Free-formed frameworks are architecturally appealing constructions. They allow for maximum creative freedom as well as for a structural optimization of the support structure. The design and construction of these kind of structures is complex however, and therefore challenging, with each frame member having an individual length, each cladding plate an individual dimension and especially each knot having an individual geometry. The result is that geometry optimization and production technology become the most important processes when striving for an economic and ecological construction. The goals of the authors are the automation of the design process by applying a parametric model and the collection of the complete complexity in the knots as well as the production of these knots without material wastage by additive manufacturing. The development process was split into three different phases: (1) Preliminary experiments determining the tension, compression and bending load-bearing behavior of the knots produced by additive manufacturing, using different polymer-based materials: ABS, ASA, PA-CF, PA6CT, PCX, PETG and a mixture of PLA and ABS. (2) Development of an automated digital workflow for the design and production of these structures by the use of a parametric approach. (3) Design, production and assembly of a full-scale prototype in the form of a free-formed shell structure spanning an area of 20 m2. The prototype was made from fumed oak wood members in combination with white stained plywood panels connected by knots produced by Fused Filament Fabrication (FFF) additive manufacturing, using polymer-based materials and screws. At the end of the contribution, a summary and an outlook on further research is given. [ABSTRACT FROM AUTHOR]

Surface engineering promotes possibilities to develop sustainable solutions to icing challenges. Durable icephobic solutions are under high interest because the functionality of many surfaces can be limited both over time and in icing conditions. To solve this, one potential approach is to use thermally sprayed polymer or composite coatings with multifunctional properties as a novel surface design method. In thermal spraying, coating materials and structures can be tailored in order to achieve different surface properties, e.g., wetting performance, roughness and protection against several weathering and wearing conditions. These, in turn, are beneficial for excellent icephobic performance and surface durability. The icephobicity of several different surfaces are tested in our icing wind tunnel (IWiT). Here, mixed-glaze ice is accreted from supercooled water droplets and the ice adhesion is measured using a centrifugal adhesion tester (CAT). The present study focuses on the icephobicity of thermally sprayed coatings. In addition, surface-related properties are evaluated in order to illustrate the correlation between the icephobic performance and the surface properties of differently tailored thermally sprayed coatings as well as compared those to other coatings and surfaces. [ABSTRACT FROM AUTHOR]

This paper presents a conceptual framework for the optimization of environmental sustainability in engineering projects, both for products and industrial facilities or processes. The main objective of this work is to propose a conceptual framework to help researchers to approach optimization under the criteria of sustainability of engineering projects, making use of current Machine Learning techniques. For the development of this conceptual framework, a bibliographic search has been carried out on the Web of Science. From the selected documents and through a hermeneutic procedure the texts have been analyzed and the conceptual framework has been carried out. A graphic representation pyramid shape is shown to clearly define the variables of the proposed conceptual framework and their relationships. The conceptual framework consists of 5 dimensions; its acronym is ADAPTS. In the base are: (1) the Application to which it is intended, (2) the available DAta, (3) the APproach under which it is operated, and (4) the machine learning Tool used. At the top of the pyramid, (5) the necessary Sensing. A study case is proposed to show its applicability. This work is part of a broader line of research, in terms of optimization under sustainability criteria. [ABSTRACT FROM AUTHOR]

This paper examines the actual knowledge regarding Building Performance Simulation Tools (BPSTs) of recent graduate architects in Spain. BPSTs quantify aspects of building performance that are relevant to design, construction, and operation. Recent graduate architects are those who have been awarded a first degree from a university or college and face their first professional experience. This article aims to identify the deficiencies within the current curricula of Spanish universities relating to BPSTs. The authors have surveyed 171 recent graduate architects, and the analysis of the data reveals the deficiencies in university education. Regarding the collected results, the Spanish university syllabi must undergo necessary modifications to encourage the use of simulation as a part of university training courses. The incorporation of energy simulation in such training courses can provide recent graduate architects with tools that would assist them during the design stage. The use of these tools is key in the development of innovative pedagogy-based teaching materials for the courses. In this sense, the present work aims to delve into the usage deficiencies associated with BPSTs and propose ways in which to bridge the gap between higher education and first professional experiences. [ABSTRACT FROM AUTHOR]

Although security is an integral aspect of any web application's growth, sustainability is also a pivotal factor in maintaining the web application. It is clear that the software industry aims to develop different methods and initiatives for achieving high security while maintaining high sustainability. Unfortunately, web application protection is useless if the sustainability is low. Thus, the present day need calls for innovation in developing web applications that afford sustainable-security to the users. By improving sustainability along with web application protection, underlying security and sustainability attributes play a vital role in determining the symmetrical effect of the sustainability and security attribute to achieve the best outcome. Sustainability evaluation, therefore, uses security and sustainability qualities to achieve the desired sustainability security solutions. In this study, ten consecutive versions of two web applications were used to determine symmetrical sustainability. The authors used the Fuzzy Analytic Hierarchy Process (Fuzzy-AHP) mechanism to determine sustainability goals and long-term impact. Furthermore, the effect of security on sustainability is assessed, and vice versa. The findings in the paper will prove to be valuable for improving sustainability of the web application. [ABSTRACT FROM AUTHOR]

There is an urgent need for educational institutions to produce graduates with appropriate skills to meet the growing global demand for professionals in the sustainable energy industry. For universities to stay at the forefront of meeting this global demand from industry, universities need to ensure their curricula and pedagogies stay relevant. The use of benchmarking is a key means of achieving this and ensuring any gap between university curricula and the practical needs of industry is minimized. The aim of this paper is to present an approach to benchmarking a sustainable energy engineering undergraduate degree with respect to curriculum frameworks recommended by industry and pedagogy standards required and recommended by academia and education research. The method uses the Murdoch University renewable energy engineering degree major as a case study. The results show that the learning outcomes of the renewable energy engineering units, in general, align well with the recommended learning outcomes for a complete sustainable energy degree, as prescribed by the Australian Government Office for Learning and Teaching. In addition, assessment task and marking criteria for the capstone unit of the major were at Australian Universities' standard. A similar approach to benchmarking can be adopted by developers of new or existing sustainable energy engineering degrees in order to align with curriculum frameworks and pedagogy standards required by industry and academic peers. [ABSTRACT FROM AUTHOR]

Among the available solutions for building heating and cooling, district heating (DH) and district cooling (DC) systems are considered some of the best options since they can ensure a better control of pollutant emissions and greater efficiency than individual systems. Nevertheless, improvements are needed to increase their sustainability and reliability. The so-called "low temperature district heating" (LTDH) concept has been introduced in recent years in an attempt (i) to reduce the distribution heat losses through a temperature decrease in the DH network, (ii) to favor the integration with renewable energy sources, and (iii) to create the conditions required for the development of future smart energy systems. However, many concerns have been raised about its implementation in both existing and new systems. For this reason, this paper aims to identify the stakeholders' ranking of the barriers against LTDH system development and implementation over the next few years. Aiming to this, a questionnaire was designed, including an analysis of current gaps and strengths, and then submitted to more than 50 Italian and international experts in the field of DH. An in-depth analysis of the received answers was performed, focusing in particular on the Italian experts' answers. Comments and suggestions on how to promote the transition to the new LTDH approach are reported. [ABSTRACT FROM AUTHOR]

The catalytic activity of both ZIF-8 and Zr/ZIF-8 has been investigated for the synthesis of chloromethyl ethylene carbonate (CMEC) using carbon dioxide (CO2) and epichlorohydrin (ECH) under solvent-free conditions. Published results from literature have highlighted the weak thermal, chemical, and mechanical stability of ZIF-8 catalyst, which has limited its large-scale industrial applications. The synthesis of novel Zr/ZIF-8 catalyst for cycloaddition reaction of ECH and CO2 to produce CMEC has provided a remarkable reinforcement to this weak functionality, which is a significant contribution to knowledge in the field of green and sustainable engineering. The enhancement in the catalytic activity of Zr in Zr/ZIF-8 can be attributed to the acidity/basicity characteristics of the catalyst. The comparison of the catalytic performance of the two catalysts has been drawn based on the effect of different reaction conditions such as temperature, CO2 pressure, catalyst loading, reaction time, stirring speed, and catalyst reusability studies. Zr/ZIF-8 has been assessed as a suitable heterogeneous catalyst outperforming the catalytic activities of ZIF-8 catalyst with respect to conversion of ECH, selectivity and yield of CMEC. At optimum conditions, the experimental results for direct synthesis of CMEC agree well with similar literature on Zr/MOF catalytic performance, where the conversion of ECH, selectivity and the yield of CMEC are 93%, 86%, and 76%, respectively. [ABSTRACT FROM AUTHOR]

The safe disposal of high-level radioactive waste (HLW) is a major issue to ensure environmental protection and the sustainable development of the nuclear energy industry; it is also an equally important issue regarding nuclear safety. Deep-buried geological disposal is recognized worldwide as the safest and most feasible way to protect human beings and the environment. To satisfy the research functions, most underground research laboratories (URLs) for geological repositories are buried deeply, and their layout is quite complex. To research nonlinear deformation characteristics and failure mechanism of deep underground caverns in the process of construction, we developed an intelligent true triaxial non-uniform loading/unloading model test system. The system has the advantages of a large rated output, starting from zero pressure, cyclic loading and unloading, high loading accuracy and displacement test accuracy, and arbitrary adjustment of device size. We carried out a true three-dimensional physical model test, taking the URL for the deep-buried geological disposal of HLW in Beishan area, Gansu Province as the prototype. The nonlinear deformation characteristics and the law of displacement change of the underground laboratory caverns are reproduced. We observed the whole process, from the appearance of micro cracks to the expansion of the cracks and the collapse of the cavern group. This provides an important experimental basis for optimizing the design and construction of URL for the deep-buried geological disposal of HLW. The value and slope of displacement calculated by the numerical simulation are mainly the same as the experimental results of the geological model test, which validates the accuracy and reliability of the model test system in this study. [ABSTRACT FROM AUTHOR]

This study proposes a method to estimate the appropriability of renewable energy resources at the global scale, when Earth system boundaries/needs and the human demand for chemical energy are respected. The method is based on an engineering approach, i.e., uncertainties of parameters and models are considered and potentials calculated with 99 % confidence. We used literature data to test our method and provide initial results for global appropriable technical potentials (ATP) that sum up to 71 TW , which is significantly larger than the current global energy demand. Consequently, there is sufficient renewable energy potentially available to increase energy access for a growing world population as well as for a development towards increasingly closed material cycles within the technosphere. Solar energy collected on the built environment ( 29 % ) and in desert areas ( 69 % ) represent the dominant part of this potential, followed in great distance by hydro ( 0.6 % ), terrestrial heat ( 0.4 % ), wind ( 0.35 % ), and biomass ( 0.2 % ). Furthermore, we propose indicators to evaluate an energy mix on different levels, from an energy mix in single products to the mix used by the global economy, against the estimated RE potentials, which allow an evaluation and consideration in the design of sustainable–circular products and systems. [ABSTRACT FROM AUTHOR]

This paper is built upon the deformation-assisted joining of sheets to tubes, away from the tube ends, by means of a new process developed by the authors. The process is based on mechanical joining by means of form-fit joints that are obtained by annular squeezing (compression) of the sheet surfaces adjacent to the tubes. The concept is different from the fixing of sheets to tubes by applying direct loading on the tubes, as is currently done in existing deformation-assisted joining solutions. The process is carried out at room temperature and its development is a contribution towards ecological and sustainable manufacturing practices due to savings in material and energy consumption and to easier end-of-life disassembly and recycling when compared to alternative processes based on fastening, riveting, welding and adhesive bonding. The paper is focused on the main process parameters and special emphasis is put on sheet thickness, squeezing depth, and cross-section recess length of the punches. The presentation is supported by experimentation and finite element modelling, and results show that appropriate process parameters should ensure a compromise between the geometry of the mechanical interlocking and the pull-out strength of the new sheet–tube connections. [ABSTRACT FROM AUTHOR]

Buildings currently consume 36% of the world's energy and contribute nearly 40% of CO2 emissions. Many countries desire to generate virtual models of their nation's buildings in order to coordinate research activities and inform market opportunities for a more sustainable built environment. The United States Department of Energy uses a suite of Commercial Prototype Building Models, which currently includes 16 building types and covers 80% of US commercial floorspace. Efforts are underway to expand this suite by developing prototype models for additional building types. In this paper, we outline a systematic approach to defining the building, collecting relevant information and creating a flexible model while doing so in the pragmatic context of a courthouse building. Informed by building design guides, databases, documented projects and inputs from courthouse design experts, we define a small, 69,324 ft2 (6440 m2), four-courtroom, low-rise courthouse as the prototype to represent an average-size courthouse in the US. We present building characteristics relevant for energy model development and provide the rationale for their selection. These details combined with climate- and construction-vintage-specific requirements for the building envelope and systems from building standards will be used for developing the courthouse model for the Commercial Prototype Building Models suite. The comprehensive information presented will also guide model modification to capture the dynamics of smaller or larger courthouses more accurately for building or system size-specific research. [ABSTRACT FROM AUTHOR]