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This paper investigates the impacts of weather shocks on athlete performance, focusing on soccer players in the Chinese Soccer Super League over three consecutive seasons from 2014 to 2016. Utilizing daily meteorological data, we construct the temperature and precipitation bin variables to explore the marginal effects on the physical and cognitive performance of soccer players. The empirical findings document a sizeable impact of high temperatures and heavy precipitation on players' performance indicators, including physical performance and cognitive performance. Specifically, relative to conditions with temperatures below 15 °C, the total running distances, the number of passes, and the number of fouls for soccer players significantly decrease by 7.6%, 6.0%, and 23.1%, respectively, when temperatures exceed 30 °C. The results for precipitation bins show that relative to conditions with precipitation below 0.1 mm, the total running distances, the number of passes, and the number of fouls for soccer players significantly decrease by 1.2%, 8.2%, and 4.7%, respectively, when precipitation exceeds 50 mm. Moreover, the heterogeneity analysis reveals that the negative effects of high temperatures and heavy precipitation are more pronounced and significant for older players, for matches performed away from home, and for matches performed in areas with higher temperatures or more precipitation. Evidence of player adaptations suggests that players from regions with higher temperatures or more precipitation perform better in terms of physical and cognitive abilities when playing in areas with lower temperatures or less precipitation compared to players from regions with lower temperatures or less precipitation when they compete in areas with higher temperatures or more precipitation. Finally, policy suggestions are proposed to mitigate the impact of weather shocks on soccer players and to promote the sustainability of the soccer industry. [ABSTRACT FROM AUTHOR]

The concrete industry has been responsible for significant depletion of natural resources and at end-of-life significantly contributes to global waste production. To date experimental studies have typically explored the use of single generation recycled aggregates (RA) in concrete production, however, to move towards a circular economy the concrete industry needs to embrace the use of multi-generation recycled aggregate concrete (MGRAC). In this paper the physical and mechanical performance of 45 concrete mix designs over 4 generations of concrete production is explored. At each generation a series of mixes are conducted at various water to cement ratios (w/c) and with a range of blends of virgin and recycled aggregates from differing generations to capture the impact on material properties. The physical and mechanical properties are quantified for both the aggregates and the concretes at each generation. The results show that the physical properties and some mechanical properties of the concrete and RA decrease with respect to virgin aggregate concrete and virgin aggregate but, implementing a 50% replacement of VA can slow down intergenerational degradation. Furthermore, the blending RA from a range of generations can also slow intergenerational degradation but to a lesser extent. Effective aggregate properties are determined, and direct relationships confirmed indicating potential for informed mix design based on an understanding of a few simple aggregate properties. [ABSTRACT FROM AUTHOR]

To dispose of the construction spoil (CS) sustainably, using alkali-activated slag (AAS) to solidify CS and prepare solidified construction spoil (SCS) as building materials has great potential. The effects of alkali concentration (Na 2 O%), modulus, binder-soil ratio (B/S), liquid-solid ratio, and sand content on the fluidity, compressive strength, water resistance, and carbon emission factor of SCS were studied via orthogonal experimental methods. It was found that the increasing fluidity was mainly affected by the increasing sand content and liquid-solid ratio, and the increasing compressive strength, water resistance, and carbon emission factor were mainly affected by the increasing Na 2 O% and B/S. Compared with cement, using AAS can reach higher fluidity, compressive strength, and water resistance, and lower carbon emissions of SCS. Finally, considering the influence of sand content on the properties of SCS, the sand washing decisions during the disposal process were reevaluated via life cycle assessment (LCA). Compared to transportation and landfill, preparing SCS with or without washing sand can significantly reduce equivalent carbon emissions, and the latter can result in lower equivalent carbon emissions and better working and physical performance of SCS than the former. From practical engineering considerations, it was suggested that the CS with low sand content doesn't need to wash sand. [ABSTRACT FROM AUTHOR]

Chrome tanning system has been faced with great challenges from potential environmental and human health risks and environmental pressures in the leather industry. The development of chrome-free tanning system towards eco-friendly leather manufacture is the main strategy to solve them from the source. However, appropriate assessments of the physical and environmental properties of a new tanning process remain challenging. In this work, we compared the physical performances and environmental impacts of two nanosilicates-based chrome-free combination tanning systems with conventional chrome tanning system in practical fur leather processing. The objective of this study was to obtain comprehensive insights into the nanosilicates-based chrome-free combination tanning systems from both technical and environmental perspectives. All fur leathers possessed similar and integrated fleece structures, ensuring high glossy and flexibility of final fur leather articles. Tara tannin-Zeolite (TA-ZE) combination tanning system was chosen as the most promising one for manufacturing garment leather articles. The resultant leathers were endowed with favorable physical properties (e.g., tear strength of 15.9 N, elongation at break of 42.3%, shrinkage temperature of 98.6 °C) and no restricted Cr(VI) and free formaldehyde. Life cycle assessment (LCA) results revealed that the TA-ZE combination tanning system exhibited better environmental impacts than other options. The main novelties included the contribution to avoiding the use of high-risk tanning chemicals by presenting a better technical and environmental alternative in the leather processing and the application of LCA to environmentally evaluate the leather processing. We envision these findings can offer comprehensive insights into emergent chrome-free combination tanning systems for designing and rationalizing feasible fur leather processing towards eco-friendly leather manufacture. [Display omitted] • Physical performances and environmental impacts of fur leather manufacture were compared. • TA-ZE tanning system produced the fur leathers with more favorable technical properties. • TA-ZE combination tanning system exhibited better environmental results. • LCA was needed to assure that chrome free tanning alternatives were environmentally better. [ABSTRACT FROM AUTHOR]

Conceptual design evaluation is a vital stage of new product development, which determines the sustainability, safety, quality of the final design, as well as its impact on the production cycle cost and manufacturability. Notwithstanding, pertinent evaluation methods advocate quantifying the subjective assessments of conceptual schemes (CSs) by decision makers (DMs) based on qualitative evaluation objectives, but the lack of physical performance verification of CSs with respect to quantitative objectives, leading to inconsistency between the optimal CS and the actual design requirements. To fill the issue, a quantitative simulation-based CS evaluation approach integrating bond graph and rough VIKOR is proposed. First, the bond elements that satisfy the physical effects corresponding to the realization of the function is obtained by function-effect mapping, and the functional structure is transformed into a bond graph model. Second, the AMESim components that satisfy the mathematical model of the above bond graph model are sought, the simulation model without detailed structural parameters is constructed to realize the simulation analysis of the scheme performance. Third, the rough VIKOR model is used to integrate the simulation data and the subjective assessments for the optimal ranking of CSs under uncertainty. Besides, rough number is introduced to aggregate the evaluation information of multi-DMs to improve the objectivity of decision process. Eventually, a cutting variable-speed device case study is further employed to verify the proposed simulation approach, and comparison results show that the proposed model can provide design decision support for value product development and reduce the waste of design resources through early design verification. • Function-effects mapping is used to transform functional model into a bond graph. • Construct a simulation model of the scheme bond graph based on AMESim components. • Rough set technology is used to aggregate simulation data and subjective evaluation. • Case verification of cutting speed change device scheme of the shearer. [ABSTRACT FROM AUTHOR]

Conceptual design evaluation is a vital stage of new product development, which determines the sustainability, safety, quality of the final design, as well as its impact on the production cycle cost and manufacturability. Notwithstanding, pertinent evaluation methods advocate quantifying the subjective assessments of conceptual schemes (CSs) by decision makers (DMs) based on qualitative evaluation objectives, but the lack of physical performance verification of CSs with respect to quantitative objectives, leading to inconsistency between the optimal CS and the actual design requirements. To fill the issue, a quantitative simulation-based CS evaluation approach integrating bond graph and rough VIKOR is proposed. First, the bond elements that satisfy the physical effects corresponding to the realization of the function is obtained by function-effect mapping, and the functional structure is transformed into a bond graph model. Second, the AMESim components that satisfy the mathematical model of the above bond graph model are sought, the simulation model without detailed structural parameters is constructed to realize the simulation analysis of the scheme performance. Third, the rough VIKOR model is used to integrate the simulation data and the subjective assessments for the optimal ranking of CSs under uncertainty. Besides, rough number is introduced to aggregate the evaluation information of multi-DMs to improve the objectivity of decision process. Eventually, a cutting variable-speed device case study is further employed to verify the proposed simulation approach, and comparison results show that the proposed model can provide design decision support for value product development and reduce the waste of design resources through early design verification. • Function-effects mapping is used to transform functional model into a bond graph. • Construct a simulation model of the scheme bond graph based on AMESim components. • Rough set technology is used to aggregate simulation data and subjective evaluation. • Case verification of cutting speed change device scheme of the shearer. [ABSTRACT FROM AUTHOR]

Large amounts of coal gangue and municipal sludge are generated from coal mining and municipal sewage. Some scholars have studied their use in ceramics, concrete, land reclamation and so on. However, in current study, heavy metals in coal gangue and municipal sludge in utilization have not been safely controlled, and there are potential risks to the ecological environment and human health. Therefore, this study systematically investigated the basic physical and chemical properties of coal gangue and municipal sludge samples, the ecological environment safety risk of heavy metals and other harmful substances (soluble phosphorus and fluorine). The results showed that the main compositions of coal gangue and municipal sludge samples were cristobalite, hematite and anorthite, which can be used as raw material for ceramsite preparation. The characteristic heavy metals in coal gangue and municipal sludge were As, Cd, Cu, Ni and Zn, which had certain environmental risks. When the optimum proportion of coal gangue: sludge = 70: 30, adding clay and blowing agent as auxiliary materials to make ceramsite, its properties, including bulk density, cylinder pressure strength and other physical properties, meet the Chinese standard "light aggregate and its test method" (GB/T 17431). The heavy metal environment and human health assessment model of the product was constructed, in which the risk assessment results are, that the content of characteristic heavy metals in ceramsite was significantly reduced, and this content conformed to the requirements of heavy metals in the Chinese standard "technical specification of cement kiln cooperative disposal of solid waste" (GB/T 30760), riskless to the human body and external environment. The compressive strength of the two kinds of ceramsite concrete can reach LC35, and the density grade was 1400–1650 N/m3, which meets the requirements of Chinese standard "technical specification for lightweight aggregate concrete" (JGJ 51). All the properties of this product meet the corresponding standards and there was no risk to the external environment, to provide theoretical guidance for the harmless and resource utilization of urban sludge and coal gangue. [ABSTRACT FROM AUTHOR]

In this study, an eco-cement was synthesized primarily from municipal solid waste incineration (MSWI) residues and appraised as a stand-alone binder in concrete. In addition to thorough laboratory testing, appraisal was extended to a pilot trial involving full-scale masonry unit production. The raw feed of the contrived eco-cement was supplemented by fractional additions of calcium hydroxide (6 wt %) and sintered at a clinkering temperature of 1100 °C. The resulting clinker (eco-cement) demonstrated latent hydraulicity when reacted with water and strong carbonation reactivity when reacted with carbon dioxide. Carbonation curing was found to both increase and accelerate strength-yield – achieving almost 1.5 times the ultimate 90-day hydraulic strength in just one day – without compromising additional latent strength gains from subsequent hydration. The binder performance was benched against control specimens prepared from ordinary Portland cement (OPC). The study's final "eco-concrete" was activated by carbonation for early strength and further hydrated for latent strength. Eco-concrete demonstrated improved durability over conventional concrete according to surface resistivity, freeze-thaw, and drying-shrinkage evaluations. Moreover, leaching results for commonly regulated heavy metals and chlorine confirmed the environmental stability of eco-concrete according to the adopted standard testing protocol. Finally, the field pilot demonstrably validated eco-concrete's suitability as a commercial product, where manufactured full-size concrete masonry units (CMUs) met all physical and performance requirements of CSA-A165 and ASTM-C90 standards. The synthesis of eco-cement, and its use as a carbon-sequestering alternative binder in eco-concrete, holds reasonable merit for consideration as an adaptable cleaner production to improve current-day MSW incineration practice. [ABSTRACT FROM AUTHOR]

This research aims to study how feasible it is to apply water-based drilling cuttings (WDC), Phosphogypsum (PG) and fly-ash in a coordinated way in aerated concrete, while also adopting non-autoclaved technology which can greatly save energy consumption. So the physiochemical properties, analysis of the microstructure and the environment performance of the WDC were analyzed. In the meantime, the process of hydration of all products of non-autoclaved aerated concrete including WDC were studied by using XRD, FT-IR and SEM. The findings revealed that the benzene series of WDC is all non-detected, and the heavy metals' results of single factor index method and potential ecological environment risk were all meet the standard. The contents of heavy metals in WDC are under the level of national standard. As well as, the WDC are rich in calcium, silicon and aluminium, and the particle size is concentrated in 30 μm. This chemical and particle characteristic makes them have the basic conditions as mineral admixtures. So, the optimum mixture ratio of aerated concrete is 2.7-13.6% for WDC, 13.6-27.3% for fly-ash, 20% for cement, 11.8% for quicklime and 1.8% for phosphogypsum, and premise condition is W/S is 0.62, curing temperature and time are 80 °C and 12 h, respectively. The unit weight together with the mechanical properties of the aerated concrete that has 40% WDC (instead of 40% fly-ash) all satisfy the B06, A3.5 GB/T11968-2006 standards. Other tests were carried out to determine its environmental performance. It established that the production of aerated concrete with 40% WDC does not result in any secondary contamination. Also, based on these properties of WDC aerated concrete we propose main technology and process route of the industrial practice. [ABSTRACT FROM AUTHOR]

Wet-white tanning system for chrome-free leather processing has been deemed as a feasible alternative from the source to effectively eliminate potential environmental and human health risks of conventional chrome tanning. This work presents a novel sustainable chrome-free leather processing based on lightfast wet-white tanning system of hydrolysable Tara tannins synergized with synthetic clay nanoplatelets (Laponite) and active aluminium salts (Lutan@ BN). The results show that the introduction of BN can significantly enhance the hydrothermal stability of wet-white leathers. The novel wet-white tanning system selected as 10% Tara–1% Laponite–3% BN for 2 h can endow the wet-white leathers with a shrinkage temperature (T s) above 95 °C. Moreover, Tara–Laponite–BN complexes can be in-situ formed on the surface of the collagen fibers or between collagen fibrils within the collagen fiber strands, stabilizing primary and conformational structures of the collagens. Notably, the incorporation of BN within the collagens can increase the isoelectric point (IEP) of the leather matrix and facilitate exhaustions of anionic post-tanning chemicals in chrome-free leather processing. The resultant leather exhibits pleasant pastel color, favorable light-fastness, and reasonable physical performances without containing restricted hazardous Cr(VI) and free formaldehyde in accordance with current Chinese standard requirements for furniture leather and European Union Eco-label criteria. These results will provide more perspectives for designing and rationalizing sustainable chrome-free leather processing towards eco-leather manufacture. Image 1 • A novel sustainable chrome-free leather processing has been developed. • The introduction of aluminium salts enhances exhaustions of anionic chemicals. • The resulting chrome-free leather exhibits improved physical properties. [ABSTRACT FROM AUTHOR]

Waste tires aggravates the two major international problems of energy supply and environmental pollution in the world. Pyrolysis can convert wasted tire to valuable fuel resources, has become attractive technology. Pyrolysis carbon black (CBp) is the main secondary product of the pyrolysis of waste tires, accounting for about 35%. The high value application of CBp is one of the bottlenecks in the waste tire pyrolysis industry. Generally, the properties of CBp/rubber composites cannot meet the requirements of tires because of its poor reinforcement and dispersion. Aim to solve this problem, a novel approach which is atomization dispersion and high temperature sputtering drying (ADSD method) is applied. To evaluate the ADSD method, the performances of CBp/rubber composites prepared by different processing methods were investigated. Experimental results revealed that the performance of CBp/rubber composites prepared by ADSD method is better than that by the traditional method in terms of vulcanization performance, physical and mechanical performance, dynamic performance, etc. The feasibility of preparing rubber composites by using CBp is also verified. Image 1 • A approach for reapplication of carbon black recovered from waste tires pyrolysis (CBp) to composites. • A combination of atomization dispersion and high sputtering temperature drying synergistic treatment. • The feasibility of preparing composites by using CBp is verified. [ABSTRACT FROM AUTHOR]