Sustainability

20 pages, 1336 KiB

Open AccessArticle

Does Urban Agglomeration Promote the Development of Cities? Evidence from the Urban Network Externalities

by Wenfang Fu, Chuanjian Luo and Modan Yan

Sustainability 2023, 15(12), 9850; https://doi.org/10.3390/su15129850 - 20 Jun 2023

Cited by 1 | Viewed by 1328

This paper discusses whether urban agglomeration can promote urban growth from the perspective of network externalities. Although agglomeration externalities play an important role in promoting regional development, improved accessibility makes urban network externalities an influential force in reshaping regional economic growth. This paper [...] Read more.

This paper discusses whether urban agglomeration can promote urban growth from the perspective of network externalities. Although agglomeration externalities play an important role in promoting regional development, improved accessibility makes urban network externalities an influential force in reshaping regional economic growth. This paper identifies the urban network based on the data of train frequency and travel time data among 271 cities in China. Then, the spatial Durbin model is used to investigate the effect of urban agglomeration on economic growth from the perspective of urban network externalities. The results demonstrate that there are significant network externalities among cities in China, which play a pivotal role in boosting urban growth. Interactions among cities produce cross-regional spillovers, causing network externalities to no longer be dependent on geographical proximity. This is significantly different from agglomeration externalities that are limited to a certain regional scale. As the scope of the urban network expands, network externalities become more pronounced. Different regional characteristics all lead to heterogeneous results of network externalities. The construction of high-speed railways, as well as the well-developed urban network system, strengthen the positive impact of network externalities. Smaller cities benefit more from higher-level urban networks than regional networks. Full article

(This article belongs to the Section Sustainable Urban and Rural Development)

► Show Figures

Figure 1

18 pages, 10366 KiB

Open AccessArticle

Experimental and Numerical Study on the Mechanical Performance of Ultra-High-Performance Concrete T-Section Beams

by Jianluan Li, Yonggao Yin and Jing Yan

Sustainability 2023, 15(12), 9849; https://doi.org/10.3390/su15129849 - 20 Jun 2023

Cited by 1 | Viewed by 1119

Abstract

Aiming to investigate the mechanical performance of UHPC T-section beams, five specimens are fabricated and tested, considering the variable steel fiber volume fraction (SFVF). The code of the Association Francaise de Génie Civil (AFGC) is evaluated by test data. Additionally, based on Abaqus [...] Read more.

Aiming to investigate the mechanical performance of UHPC T-section beams, five specimens are fabricated and tested, considering the variable steel fiber volume fraction (SFVF). The code of the Association Francaise de Génie Civil (AFGC) is evaluated by test data. Additionally, based on Abaqus (2020), refined finite element analysis (FEA) models of specimens are established and validated by experimental data. Moreover, the parametric sensitivity analysis is carried out, which aims to further investigate the effect of shear span ratio, longitude reinforcement ratio, and stirrup ratio on the bending-shear behavior of T-section beams. The test results indicated that the ultimate load of the specimen improves with the increase of SFVF, and the use of steel fibers can greatly improve the shear capacity instead of the bending capacity. Furthermore, SFVF can change the failure mode; the specimens fail in shear failure when SFVF < 2%, while they fail in bending failure when SFVF ≥ 2%. From the evaluation of codes, the AFGC code is conservative in the prediction of ultimate capacity, which can guide the design of UHPC structures well. Additionally, from the parametric analysis of FEM, the failure mode transformed from shear failure to bending failure as the shear span ratio increased, particularly in specimens with SFVF ≥ 2.5%. Moreover, the stirrup ratio ρ_sv has a significant effect on the shear performance of structures with SFVF ≤ 1%, while it has less effect with SFVF ≥ 2%. Full article

(This article belongs to the Topic New Trends in Advanced Construction Technology, Sustainable Construction Materials and High-Performance Building Structures)

► Show Figures

Figure 1

13 pages, 1825 KiB

Open AccessArticle

Unravelling the Release Kinetics of Exchangeable Magnesium in Acid Soil of Nilgiris

by Munmun Dash, Subramanium Thiyageshwari, Duraisamy Selvi, Rangasamy Anandham, Karuppusamy Rajan, Djanaguiraman Maduraimuthu, Santosh Kumar Singh, Jagadesh Muthumani, Shivvendra Singh and Biswajit Pramanick

Sustainability 2023, 15(12), 9848; https://doi.org/10.3390/su15129848 - 20 Jun 2023

Cited by 1 | Viewed by 1238

Abstract

Magnesium deficiency is a pervasive and recurrent factor that significantly restricts crop production, primarily attributable to the low levels of exchangeable magnesium (ex-Mg) present in acidic soil conditions. This deficiency exerts a pronounced negative influence on the sustainability and progress of agricultural development. [...] Read more.

Magnesium deficiency is a pervasive and recurrent factor that significantly restricts crop production, primarily attributable to the low levels of exchangeable magnesium (ex-Mg) present in acidic soil conditions. This deficiency exerts a pronounced negative influence on the sustainability and progress of agricultural development. Hence the current study aspired at modeling the kinetics of Exchangeable Magnesium release from 3 fertilizer sources i.e., Epsom salt (MgSO₄·7H₂O), Magnesite (MgCO₃) and Dolomite [CaMg(CO₃)₂] in the acidic soil of the Nilgiris district in Tamil Nadu, India. Four mathematical models were verified—Power function, parabolic diffusion, Simple-Elovich, and first-order to explain cumulative Mg²⁺ release. Power function was noticed to be an outstanding empirical equation finely fitted to the experimental data. The intensity, as well as the modality of the release pattern, was predicted by the numerical parameters. The power function as well as Parabolic Diffusion portrayed the Mg²⁺ release kinetics best as verified by the maximum correlation coefficients (r²). The parabolic diffusion model also designated the data as suitable, signifying diffusion-controlled exchange. From the derived dissolution rates, it was conceivable to agree Epsom salt (MgSO₄·7H₂O) from which the release was faster than the other two magnesium sources. In conclusion, these outcomes provided an insight into the temporal dynamics of magnesium availability in acidic soil, highlighting the importance of understanding its release kinetics for sustainable agriculture development. The findings contribute to the broader knowledge of magnesium management strategies, aiding in the development of targeted interventions to alleviate magnesium deficiency and optimize crop productivity in acidic soil environments. Full article

(This article belongs to the Special Issue Soil Fertility and Plant Nutrition for Sustainability)

► Show Figures

Figure 1

53 pages, 8015 KiB

Open AccessReview

A Comprehensive Review on Power-Quality Issues, Optimization Techniques, and Control Strategies of Microgrid Based on Renewable Energy Sources

by Emmanuel Hernández-Mayoral, Manuel Madrigal-Martínez, Jesús D. Mina-Antonio, Reynaldo Iracheta-Cortez, Jesús A. Enríquez-Santiago, Omar Rodríguez-Rivera, Gregorio Martínez-Reyes and Edwin Mendoza-Santos

Sustainability 2023, 15(12), 9847; https://doi.org/10.3390/su15129847 - 20 Jun 2023

Cited by 9 | Viewed by 2803

Abstract

Microgrids (MGs) are systems that cleanly, efficiently, and economically integrate Renewable Energy Sources (RESs) and Energy Storage Systems (ESSs) to the electrical grid. They are capable of reducing transmission losses and improving the use of electricity and heat. However, RESs presents intermittent behavior [...] Read more.

Microgrids (MGs) are systems that cleanly, efficiently, and economically integrate Renewable Energy Sources (RESs) and Energy Storage Systems (ESSs) to the electrical grid. They are capable of reducing transmission losses and improving the use of electricity and heat. However, RESs presents intermittent behavior derived from the stochastic nature of the renewable resources available on site. This can cause power-quality issues throughout the electrical grid, which can be solved by different optimization techniques and/or control strategies applied to power converters. This paper offers a detailed review of the literature regarding three important aspects: (i) Power-quality issues generated in MGs both in islanded mode and grid-connected mode; (ii) Optimization techniques used in the MGs to achieve the optimal operating conditions of the Energy Management System (EMS); and (iii) Control strategies implemented in the MGs to guarantee stability, mitigation of power-quality issues, power balance, and synchronization with the grid. It is worth mentioning that in this paper, we emphasize hybrid MGs (HMGs) since they combine the benefits of AC–MGs and DC–MGs while increasing system reliability. As the utility grid moves toward an optimal design of MG structures, this paper will serve as a foundation for future research, comparative analysis, and further development of novel techniques regarding HMGs. Full article

(This article belongs to the Section Energy Sustainability)

► Show Figures

Figure 1

14 pages, 4949 KiB

Open AccessArticle

Microstructural Analysis and Compressive Strength of Fly Ash and Petroleum Sludge Ash Geopolymer Mortar under High Temperatures

by Mubarak Usman Kankia, Lavania Baloo, Nasiru Danlami, Noor Amila Zawawi, Abosede Bello and Sadiq Ibrahim Muhammad

Sustainability 2023, 15(12), 9846; https://doi.org/10.3390/su15129846 - 20 Jun 2023

Cited by 1 | Viewed by 1143

Abstract

The development of sustainable building materials and construction to decrease environmental pollution in both production and operational stages of the materials’ life cycle is appealing to great interest in the construction industries worldwide. This study evaluated the negative effect of temperature up to [...] Read more.

The development of sustainable building materials and construction to decrease environmental pollution in both production and operational stages of the materials’ life cycle is appealing to great interest in the construction industries worldwide. This study evaluated the negative effect of temperature up to 1000 °C on the compressive strength and microstructure of fly ash and petroleum sludge ash (PSA) geopolymer mortar. A sodium silicate and sodium hydroxide mixture is used as an activator. The synthesized mortar was investigated using X-ray Diffraction (XRD), Fourier Transformation Infrared Spectroscopy (FTIR), Mercury Intrusion Porosimetry (MIP), and Field Emission Scanning Electron Microscopy (FESEM). As the temperature increased, the compressive strength of the geopolymer mortar decreased. The strength degradation is due to the damage to microstructure because of the temperature-induced dehydroxylation, dehydration thermal incompatibility between geopolymer aggregate and paste of geopolymer mortar at high temperatures. With an increase in temperature, the cumulative pore volume increased. The FESEM image showed the decomposition of the geopolymer matrix started at a temperature of 600 °C. Incorporating PSA in geopolymer mortar could result in an eco-friendly and sustainable environment that may reduce the problems associated with sludge disposal. Full article

(This article belongs to the Special Issue Sludge: A Renewable Source for Energy and Resources Recovery)

► Show Figures

Figure 1

25 pages, 385 KiB

Open AccessArticle

The Driving Factors of Green Technology Innovation Efficiency—A Study Based on the Dynamic QCA Method

by Xiaonan Fan, Sainan Ren and Yang Liu

Sustainability 2023, 15(12), 9845; https://doi.org/10.3390/su15129845 - 20 Jun 2023

Cited by 2 | Viewed by 1435

Abstract

The problems of environmental pollution and resource shortages are becoming increasingly prominent with the advances in technology and the improvements in social productivity levels. How to coordinate the innovating subjects, and strengthen the interaction and cooperation among the subjects to improve the green [...] Read more.

The problems of environmental pollution and resource shortages are becoming increasingly prominent with the advances in technology and the improvements in social productivity levels. How to coordinate the innovating subjects, and strengthen the interaction and cooperation among the subjects to improve the green technology innovation efficiency (GTI efficiency) is an important issue to be solved urgently. This paper constructs a multisubject collaborative analysis framework of “government–market–society” for the GTI efficiency based on the pluralistic co-governance theory. Using 30 provinces (or regions, cities) in China from 2016 to 2020 as research samples, we analyzed the driving factors of GTI efficiency using the dynamic QCA method. Furthermore, the configuration effects of the driving factors were further analyzed in the time and spatial dimensions. The results show that: (1) The single driving factor does not constitute the requisite condition for high GTI efficiency. (2) There are three types of paths to realize high GTI efficiency: “government–market driven”, “market–society driven”, and “government–market–society synergistic promotion”. Among them, the “government–market-driven” path is subdivided into “government—internal-market driven” and “government-supported–external-market driven”. (3) In the time dimension, the “market–society driven” path has prominently enhanced its driving effect on GTI efficiency, while the driving effect of the other three paths is little changed. In the spatial dimension, the coverage of the “government-supported–external-market driven” path appears to have obvious regional differences, and the explanation degree of the central region is higher, while the other three paths do not have obvious regional differences. Based on the perspective of configuration, these research results enrich the related research on the driving factors of GTI efficiency in the time and spatial dimension. It provides enlightenment for boosting the coordinated development of regional GTI efficiency and realizing sustainable economic growth. Full article

► Show Figures

Figure 1

36 pages, 8826 KiB

Open AccessReview

Bio-Based Polymeric Flocculants and Adsorbents for Wastewater Treatment

by Haradhan Kolya and Chun-Won Kang

Sustainability 2023, 15(12), 9844; https://doi.org/10.3390/su15129844 - 20 Jun 2023

Cited by 8 | Viewed by 3609

Abstract

With the growing demand for clean and safe water, there is a pressing need to explore novel materials for water treatment applications. In this regard, bio-based polymeric materials have emerged as a promising solution for water purification. This article highlights the numerous advantages [...] Read more.

With the growing demand for clean and safe water, there is a pressing need to explore novel materials for water treatment applications. In this regard, bio-based polymeric materials have emerged as a promising solution for water purification. This article highlights the numerous advantages offered by bio-based polymeric materials, including their biodegradability, low cost, and renewable nature. Moreover, it discusses in depth the two primary applications of these materials in water treatment, namely flocculation and adsorption, showcasing their effectiveness in removing contaminants. Furthermore, this review addresses the future prospects and challenges associated with the development of bio-based polymeric materials for water treatment applications. This review provides valuable insights for researchers in the field, driving further advancements in the utilization of bio-based polymeric materials to ensure clean and sustainable water resources. Full article

(This article belongs to the Special Issue Wastewater Treatment and Purification)

► Show Figures

Graphical abstract

20 pages, 1040 KiB

Open AccessArticle

A Systemic Material Innovation Study of the Current State and Future Possibilities for Circular Polyester

by Rosie Hornbuckle, Kate Goldsworthy and Laura Knight

Sustainability 2023, 15(12), 9843; https://doi.org/10.3390/su15129843 - 20 Jun 2023

Viewed by 1042

Abstract

This paper focuses on the current state and future potential of the most prevalent synthetic fibre, polyester, as a circular textile. The aim is to reveal areas for intervention in the current system that might lead the transition to circular polyester in the [...] Read more.

This paper focuses on the current state and future potential of the most prevalent synthetic fibre, polyester, as a circular textile. The aim is to reveal areas for intervention in the current system that might lead the transition to circular polyester in the future. A qualitative Systemic Material Innovation (SMI) study was undertaken to reveal barriers and opportunities to achieving circular polyester from a holistic perspective. Interviews were conducted with 20 industry experts, including co-designing NOW and FUTURE eco-system maps for circular polyester, and a roadmap for transition. Analysis and synthesis of the data revealed that ‘design for reuse and recycling’ is seen as central to realising circular polyester, in particular replacing elastane and ‘fleece’. Inaction by brands, the lack of granular post-use data, appropriate collection practices, and the low-cost of conventional polyester were also highlighted as barriers. Improved understanding of the life cycle impacts and actions amongst all stakeholders was seen as a key opportunity that might be leveraged through dialogue with other stakeholders. Six actions for industry and research are recommended. Data visualisation is used to translate the findings and operationalise the findings for a broad range of stakeholders in the polyester eco-system. Full article

(This article belongs to the Section Sustainable Materials)

► Show Figures

Figure 1

26 pages, 821 KiB

Open AccessArticle

Community Perceptions on the Critical Success Factors of Hotels’ Community-Based Corporate Social Responsibility

by Azilah Kasim, Siti Noormala Jailani, Muhammad Fauzi Mokhtar, Jasmine Zea Raziah Radha Rashid Radha, Bussalin Khuadthong and Maebel Leong Sai Fong

Sustainability 2023, 15(12), 9842; https://doi.org/10.3390/su15129842 - 20 Jun 2023

Viewed by 1176

Abstract

This paper examines community as the consumer of community-related corporate social responsibility (CSR). It empirically investigates the critical success factors of CSR within the context of tourism from the community perspective because, for CSR activities that are targeted towards them, understanding their perspective [...] Read more.

This paper examines community as the consumer of community-related corporate social responsibility (CSR). It empirically investigates the critical success factors of CSR within the context of tourism from the community perspective because, for CSR activities that are targeted towards them, understanding their perspective could not be more necessary. The study narrowed the gap of knowledge by testing twelve critical success factors proposed in the literature on 267 target respondents in Langkawi, Malaysia and analysed the data using PLS. The sample was drawn using a qualifying question from communities known to have participated in previous hotel CSR activities. The findings revealed that, from a community standpoint, just four of the recommended twelve variables were crucial to the performance of community-related CSR in Langkawi’s hotel industry. These variables were general community development, law and social norms, project management committee, and financial preparedness. The findings provide theoretical as well as managerial implications, which are explained in the later sections of the paper. Full article

(This article belongs to the Special Issue Sustainability and Consumer Behavior in the Service Industry)

► Show Figures

Figure 1

26 pages, 15699 KiB

Open AccessArticle

Production of CO₂ Hydrates in Aqueous Mixtures Having (NH₄)₂SO₄ at Different Concentrations; Definition of Consequences on the Process Evolution, Quantification of CO₂ Captured and Validation of Hydrates Production as Technique for Ammonium Removal from Waste Water

by Alberto Maria Gambelli, Xhino Rushani, Daniela Pezzolla, Federico Rossi and Giovanni Gigliotti

Sustainability 2023, 15(12), 9841; https://doi.org/10.3390/su15129841 - 20 Jun 2023

Viewed by 1026

Abstract

Carbon dioxide hydrates were formed in fresh water and in aqueous mixtures containing ammonium sulfate, at concentrations equal to 1.9, 6.3, and 9.5 wt%. The moles of hydrates formed were compared, to define the inhibiting strength of the electrolyte solution and the dependence [...] Read more.

Carbon dioxide hydrates were formed in fresh water and in aqueous mixtures containing ammonium sulfate, at concentrations equal to 1.9, 6.3, and 9.5 wt%. The moles of hydrates formed were compared, to define the inhibiting strength of the electrolyte solution and the dependence of inhibition from concentration. The addition of salt strongly inhibited the process and the number of hydrates produced passed from 0.204–0.256 moles, obtained in fresh water, to 0.108–0.198 moles, obtained at the lowest concentration tested. The further addition of salt still lowered the production of the hydrates; at the highest concentration tested, only 0.092–0.177 moles were obtained. The pressure-temperature evolutions of the hydrates were then discussed and compared with the ideal process and with the experimental results obtained in demineralised water. Finally, further samples of CO₂ hydrates, produced in the presence of 9.5 wt% salt in the aqueous phase (corresponding to 1.5 wt% NH₄⁺), were recovered and dissociated in a separated environment. The liquid phase, resulting from their dissociation, was subjected to spectrophotometric analyses. Its NH₄⁺ content was measured and compared with the initial concentration in water. Therefore, it was possible to quantify the capability of the system to remove the (NH₄)₂SO₄ from the water (involved in hydrate formation) and to concentrate it in the remaining liquid phase. Considering the portion of water involved in hydrates formation, the concentration of ammonium passed from 1.5 wt% to 0.38–0.449 wt%. Full article

(This article belongs to the Special Issue Ecological Aspects and Biotechnology Applications in Wastewater and Pollutants Treatment)

► Show Figures

Figure 1

13 pages, 660 KiB

Open AccessArticle

Cite Space-Based Bibliometric Analysis of Green Marketing

by Li Liu, Hailang Cui and Yuankun Nie

Sustainability 2023, 15(12), 9840; https://doi.org/10.3390/su15129840 - 20 Jun 2023

Cited by 3 | Viewed by 1620

Abstract

“Lucid waters and lush mountains are invaluable assets”. Green marketing and sustainable development have become crucial topics in economic and social development. During 2019–2023, there are nearly 952 publications on green marketing-related topics in the Web of Science core database, and a large [...] Read more.

“Lucid waters and lush mountains are invaluable assets”. Green marketing and sustainable development have become crucial topics in economic and social development. During 2019–2023, there are nearly 952 publications on green marketing-related topics in the Web of Science core database, and a large number of scholars researched green marketing, but there is still a lack of comprehensive and systematic studies on the current status of green marketing research and hot trends. The main purpose of this study is to summarize and sort out the current status of green marketing research by reviewing the literature related to green marketing (enterprises vs. consumers). Meanwhile, using Cite Space 6.2 R2 software, the core literature of green marketing in the past five years was screened, the data were visualized and analyzed, and a knowledge map of the cooperative authors, institutions, countries, and keywords was drawn in an attempt to discover the research hotspots and major development trends of green marketing. The results show that the publications and citation frequency of green marketing-related literature showed an increasing trend from 2019 to 2023, and the highest citation frequency was reached in 2022. Green marketing literature appears more frequently in the USA, China, and England and has a higher influence. Green management, firm performance, green innovation, green strategy, green capability, sustainable development, green business, green market orientation, green supply chain management, green exploitation, green responsibility, ecosystem, green commitment, green perceptions, green competitive advantage, and corporate social responsibility reflect the hot topics and important themes of green marketing research. This study innovatively combines a green marketing literature review and bibliometric analysis, comprehensively and systematically discusses the current status of green marketing research and hot trends based on both textual and data perspectives, and puts forward the “individual-environment-economy-society” virtuous ecological cycle of green marketing from a macro perspective. Full article

► Show Figures

Figure 1

31 pages, 56329 KiB

Open AccessArticle

A Novel MPPT-Based Lithium-Ion Battery Solar Charger for Operation under Fluctuating Irradiance Conditions

by Khaled Osmani, Ahmad Haddad, Mohammad Alkhedher, Thierry Lemenand, Bruno Castanier and Mohamad Ramadan

Sustainability 2023, 15(12), 9839; https://doi.org/10.3390/su15129839 - 20 Jun 2023

Cited by 4 | Viewed by 1919

Abstract

Fluctuant irradiance conditions constitute a challenge in front of a proper battery charging process, when originated from a PhotoVoltaic Array (PVA). The behavior of the PVA under such conditions (i.e., reflected by a disturbed PV characteristic curve) increases the complexity of the total [...] Read more.

Fluctuant irradiance conditions constitute a challenge in front of a proper battery charging process, when originated from a PhotoVoltaic Array (PVA). The behavior of the PVA under such conditions (i.e., reflected by a disturbed PV characteristic curve) increases the complexity of the total available power’s extraction process. This inconvenient fact yields eventually to a decreased overall efficiency of PV systems, especially with the presence of imprecise power-electronics involved circuits. Accordingly, the purpose of this paper is to design a complete battery solar charger, with Maximum Power Point Tracking ability, emerged from a PVA of 1.918 kWp, arranged in Series-Parallel topology. The targeted battery is of Lithium-Ion (Li-I) type, with 24 VDC operating voltage and 150 Ah rated current. The design began by configuring an interleaved synchronous DC-DC converter to produce a desired voltage level, with low inductor ripple current and low output ripple voltage. The DC-DC converter is in turns condemned by a modified Perturb and Observe (P&O) algorithm, to ensure efficient maximum power tracking. Progressively, the design encountered a layout of the bi-directional DC-DC converter to ensure safe current charging values for the battery. Under the same manner, the role of the bi-directional converter was to plug the battery out of the system, in case when the Depth of Discharge (DoD) is below 25%, thus sustaining the life span of the battery. The entire setup of the proposed sub-systems then leads to the relatively fastest, safest, and most reliable battery charging process. Results show an effectiveness (in terms of PV power tracking) ranging from 87% to 100% under four swiftly changing irradiance conditions. Moreover, this paper suggested the design’s future industrialization process, leading to an effective PV solar charger prototype. Full article

► Show Figures

Figure 1

14 pages, 607 KiB

Open AccessArticle

Research on the Regional Cooperation Innovation Network of Universities in the Guangdong–Hong Kong–Macao Great Bay Area

by Yan Wang and Zhihua Liu

Sustainability 2023, 15(12), 9838; https://doi.org/10.3390/su15129838 - 20 Jun 2023

Viewed by 812

Abstract

As typical innovation organizations, the structure and efficiency of cooperation among universities’ innovation behaviors are important influencing factors for regional innovation sustainable development. In 2019, the Chinese government promulgated the “Outline of the Development Plan of The Guangdong, Hong Kong and Macao Great [...] Read more.

As typical innovation organizations, the structure and efficiency of cooperation among universities’ innovation behaviors are important influencing factors for regional innovation sustainable development. In 2019, the Chinese government promulgated the “Outline of the Development Plan of The Guangdong, Hong Kong and Macao Great Bay Area”, which directly promotes a sustainable cooperation network of universities in the Great Bay Area. This study used UCINET to visualize the cooperation network of universities in Guangdong, Hong Kong, and Macao based on the cooperation data generated by 35 universities in the Guangdong–Hong Kong–Macao Great Bay Area, jointly establishing 37 professional alliances that developed 888 cooperation ties from 2017 to 2022. The results show that the current cooperative network density of universities in the Great Bay Area is high (density = 0.746), but the cohesion trend is not significant (network centralization = 26.92%); a clear circle structure has been formed. The network exhibits a narrow shape at both ends and widens in the middle; the higher the hierarchical position of universities in the region, the more likely they are to enter the core cooperation network and establish more cooperation relationships. Universities in the marginal circles find it especially difficult to initiate cooperative relationships due to their disadvantageous position in terms of limited resources and a lack of administrative intervention. The current cooperation situation still has room for expansion. Full article

(This article belongs to the Special Issue Educational Research in the Era of 2030 Agenda for Sustainable Development)

► Show Figures

Figure 1

16 pages, 483 KiB

Open AccessArticle

Preventing Oil Shock Inflation: Sustainable Development Mechanisms vs. Islamic Mechanisms

by Adel Benhamed and Mohamed Sadok Gassouma

Sustainability 2023, 15(12), 9837; https://doi.org/10.3390/su15129837 - 20 Jun 2023

Viewed by 1164

Abstract

This paper discusses the effects of both sustainable development and an Islamic system on the transmission of oil shocks into inflation. Sustainable development in this context includes wealth distribution equity, public governance effectiveness and alternative energy creation for the promotion of economic growth. [...] Read more.

This paper discusses the effects of both sustainable development and an Islamic system on the transmission of oil shocks into inflation. Sustainable development in this context includes wealth distribution equity, public governance effectiveness and alternative energy creation for the promotion of economic growth. These factors have been revised by Askari and Mirakhor under an Islamic approach using a set of Islamic indices to reflect a social, economic, political and ecological system that is in compliance with the Sharia principles. Using the ARDL model, we tested whether these Islamic mechanisms could have played the role of sustainable development in the fight against the transmission of oil shocks into inflation in MENA countries during the period 2000–2018. The results show that the Islamic system can play the role of sustainable development better than the traditional one, through fostering social equity, fighting against corruption, promoting humanity in employability and facilitating growth of the real economy. These Islamic values slow down the inflationary phenomenon caused by oil shocks. Full article

► Show Figures

Figure 1

14 pages, 2268 KiB

Open AccessArticle

Microplastic Contamination in Different Marine Species of Bintaro Fish Market, Indonesia

by Sri Widyastuti, Angga Susmana Abidin, Hikmaturrohmi Hikmaturrohmi, Bq Tri Khairina Ilhami, Nanda Sofian Hadi Kurniawan, Ahmad Jupri, Dining Aidil Candri, Andri Frediansyah and Eka Sunarwidhi Prasedya

Sustainability 2023, 15(12), 9836; https://doi.org/10.3390/su15129836 - 20 Jun 2023

Cited by 1 | Viewed by 1805

Abstract

Indonesia is among the largest fish-producing countries. The West Nusa Tenggara (WNT) region is one of the highest producers of fish in Indonesia. Hence, the levels of MP contamination in commercial fish should be assessed to ensure food safety, food security, and socio-economic [...] Read more.

Indonesia is among the largest fish-producing countries. The West Nusa Tenggara (WNT) region is one of the highest producers of fish in Indonesia. Hence, the levels of MP contamination in commercial fish should be assessed to ensure food safety, food security, and socio-economic sustainability. This study investigates MP contamination in commercial fish in one of the largest fish markets in the WNT region, the Bintaro fish market. Three commercial fish species were evaluated for MP contamination in this study, Nasso thynnoides, Auxis rochei, and Caesio teres. The highest number of MPs was detected in A. rochei (21.60 ± 8.70 MPs/100 g). The other pelagic fish species, N. thynnoides, also shown considerably high MP contamination (18.17 ± 7.93 MPs/100 g). On the other hand, the midwater fish Caesio teres showed the least MP contamination (7.07 MPs/100 g). In addition, most of the MPs detected in all three fish species were fiber MPs of small sizes (100–500 µm). Based on FTIR analyses, the MP samples from all three fish species mainly consisted of polyamide (PA), which is the polymer used to form fiber for textiles. These results potentially reveal the degree of microplastic pollution in not only coastal areas of WNT, but also Sulawesi and also East Nusa Tenggara (ENT) since the fish distributed at the Bintaro fish market came from these regions. Better solid waste management in Indonesia is needed to reduce plastic waste management, particularly household waste, which is the potential major source of fiber MPs. Full article

► Show Figures

Graphical abstract

13 pages, 3299 KiB

Open AccessArticle

Application of Improved Particle Swarm Optimization SVM in Water Quality Evaluation of Ming Cui Lake

by Zunyang Zhang, Cheng Yang, Qiao Qiao, Xuesheng Li, Fuping Wang and Chengcheng Li

Sustainability 2023, 15(12), 9835; https://doi.org/10.3390/su15129835 - 20 Jun 2023

Viewed by 932

Abstract

Water quality directly determines our living environment. In order to establish a more scientific and reasonable water quality evaluation model, it needs a lot of data support, but it will lead to a large increase in the calculation time of the evaluation model. [...] Read more.

Water quality directly determines our living environment. In order to establish a more scientific and reasonable water quality evaluation model, it needs a lot of data support, but it will lead to a large increase in the calculation time of the evaluation model. This paper proposes an improved particle swarm optimization SVM model (CPOS-SVM) to solve this problem. In this paper, the Pareto optimal solution concept is used to sparsely process the training set, which can ensure that the number of training sets is reduced without loss of data characteristics, thus reducing the training time. In order to solve the problem of the kernel parameter g and penalty factor c on the SVM algorithm, which affects the accuracy of the SVM model but it is difficult to select why, a particle swarm optimization algorithm is used in this paper to optimize the kernel parameter and penalty factor and improve the accuracy of the model. In this paper, 480 sets of data from Ming Cui Lake from 2014 to 2022 are taken as the research object, and examples are analyzed in MATLAB 2020a. The results show that the training time of the CPOS-SVM model can be completed within 2 s and does not increase with the increase of data volume. Meanwhile, by comparing the SVM model, POS-SVM model, and POS-BP model, training time increases dramatically with the amount of data. The accuracy of the POS-SVM model is the highest, and the accuracy of the CPOS-SVM model is basically consistent with that of the POS-SVM, reaching 94%, while the accuracy of the SVM model and the POS-BP model are slightly worse. This indicates that the CPOS-SVM model has good application value in water quality evaluation. Full article

(This article belongs to the Special Issue Sustainability in Water Treatment)

► Show Figures

Figure 1

38 pages, 1714 KiB

Open AccessArticle

Sustainability in Project Management and Project Success with Virtual Teams: A Quantitative Analysis Considering Stakeholder Engagement and Knowledge Management

by Gisele Blak Bernat, Eduardo Linhares Qualharini, Marcela Souto Castro, André Baptista Barcaui and Raquel Reis Soares

Sustainability 2023, 15(12), 9834; https://doi.org/10.3390/su15129834 - 20 Jun 2023

Cited by 4 | Viewed by 8396

Abstract

Project success is crucial for businesses, but the impact of virtual teams on it is still not fully understood. The global outbreak of the COVID-19 pandemic in 2020 has led to the widespread adoption of virtual environment solutions to support geographically dispersed project [...] Read more.

Project success is crucial for businesses, but the impact of virtual teams on it is still not fully understood. The global outbreak of the COVID-19 pandemic in 2020 has led to the widespread adoption of virtual environment solutions to support geographically dispersed project teams. The growth in the use of virtual or hybrid teams in projects is expected to continue, as it presents an irreversible trend. Furthermore, there has been a significant increase in interest in sustainability in project management in recent years, emphasizing the long-term perspective for project success. To address this gap and contribute to the project success theory, a quantitative study was conducted to examine the impact of stakeholder engagement, knowledge management, and sustainable practices in project management on project success in virtual work environments using structural equation modeling. Experienced Portuguese-speaking project management professionals were surveyed. No evidence was found to support the moderating role of virtual teams, concluding that the virtual nature of a team does not diminish stakeholder engagement, knowledge-sharing, or sustainability in project management and its influence on project success. This study provides valuable insights for enhancing project success in virtual work environments, as it is the first of its kind to quantitatively address the sustainable long-term approach of project success in virtual environments. Full article

(This article belongs to the Special Issue Sustainability Challenges across Industries, Services and Markets)

► Show Figures

Figure 1

19 pages, 2379 KiB

Open AccessArticle

Sustainable Development Goals and Education: A Bibliometric Review—The Case of Latin America

by Liliana Pedraja-Rejas, Emilio Rodríguez-Ponce, Camila Muñoz-Fritis and David Laroze

Sustainability 2023, 15(12), 9833; https://doi.org/10.3390/su15129833 - 20 Jun 2023

Cited by 2 | Viewed by 1459

Abstract

The aim of this article is to review Latin American scientific production on the Sustainable Development Goals (SDGs) in the field of education. For this purpose, a bibliometric analysis is performed on WoS articles, and a content analysis is carried out on empirical [...] Read more.

The aim of this article is to review Latin American scientific production on the Sustainable Development Goals (SDGs) in the field of education. For this purpose, a bibliometric analysis is performed on WoS articles, and a content analysis is carried out on empirical articles from 2015–2022. The main findings indicate that (1) since 2016, a considerable increase in scientific production is evidenced, reaching a peak of 30 articles in 2020; (2) Brazil is the most productive and influential nation in the region; (3) in general, good levels of international cooperation are evidenced, although only Brazil and Mexico show outstanding levels of scientific cooperation with countries in the Global North; (4) most of the analyzed papers were published in education journals, with a smaller percentage in specialized higher education journals; and (5) there are two main lines of research within the empirical papers: “Curriculum, extracurricular activities, projects, and pedagogical initiatives” and “Students’ behaviors, perceptions, beliefs, concerns, and level of knowledge around issues related to the SDGs”. We conclude that although Latin American production has increased in the last period, contributions continue to be marginal at global levels. Full article

(This article belongs to the Special Issue The Implications of Higher Education for Sustainable Development)

► Show Figures

Figure 1

19 pages, 360 KiB

Open AccessArticle

Corporate Social Responsibility and the Willingness to Eco-Innovate among Chilean Firms

by Luis E. Villegas, Andrés A. Acuña-Duarte and César A. Salazar

Sustainability 2023, 15(12), 9832; https://doi.org/10.3390/su15129832 - 20 Jun 2023

Cited by 2 | Viewed by 1112

Abstract

Adopting social responsibility can be a key strategy for firms to mitigate the impact of production on the environment, contributing to a more sustainable business model. Based on the triple bottom line perspective, we analyze the effect of Corporate Social Responsibility (CSR) on [...] Read more.

Adopting social responsibility can be a key strategy for firms to mitigate the impact of production on the environment, contributing to a more sustainable business model. Based on the triple bottom line perspective, we analyze the effect of Corporate Social Responsibility (CSR) on the willingness to allocate resources to eco-innovation among companies in a developing country. Firm-level data from the Fifth Longitudinal Survey of Chilean Firms are used to estimate a binary probit model for the willingness to eco-innovate and a Heckman sample-selection model for total expenditures and investment in eco-innovation. Results confirm that legal regulations and R&D efforts are drivers of eco-innovation among Chilean firms. Larger-sized and export-oriented firms also exhibit a higher willingness to eco-innovate. The main findings show a positive influence of CSR policy on the willingness to eco-innovate and on the resulting resource allocation decision. Interestingly, the evidence reveals that while financial and environmental CSR dimensions only affect the probability of adopting eco-innovation, the social CSR dimension also increases the amount firms spend on eco-innovation. This result suggests that social CSR may act as a complement to other CSR dimensions. These results are robust when controlling for firm-level specific effects under sample-selection models. Full article

(This article belongs to the Section Economic and Business Aspects of Sustainability)

17 pages, 6529 KiB

Open AccessArticle

Experimental and Theoretical Study for a Displacement-Controlled Design Method of Embedded Cantilever Retaining Walls (Piles)

by Xiaozhen Fan, Changjie Xu and Luju Liang

Sustainability 2023, 15(12), 9831; https://doi.org/10.3390/su15129831 - 20 Jun 2023

Cited by 1 | Viewed by 1106

Abstract

Displacement control is critical to the design of retaining walls, especially in urban areas, to avoid any potential damage to adjacent structures during excavations. In this study, model tests are first conducted to investigate the stress and deformation mechanisms of an embedded cantilevered [...] Read more.

Displacement control is critical to the design of retaining walls, especially in urban areas, to avoid any potential damage to adjacent structures during excavations. In this study, model tests are first conducted to investigate the stress and deformation mechanisms of an embedded cantilevered retaining (ECR) wall during excavations. The development of the wall top displacement and the active and passive earth pressures acting on the ECR walls during excavations are studied. Upon the experimental observations, a displacement-dependent earth pressure coefficient is proposed to derive an analytical solution to predict both the active and passive earth pressure acting on the ECR wall (pile), where the displacement value and displacement mode of the ECR wall (pile) are taken into account. Comparisons between the model predictions and test results are carried out. A good agreement is observed, which shows the validity of the proposed solution. Based on the proposed solution, a displacement-controlled method for the design of ECR walls (piles) that takes into account the location of the rotation point is proposed. Parametric studies are conducted to demonstrate the impact of deformation control and excavation depth on the design parameters of ECR walls (piles). Full article

► Show Figures

Figure 1

13 pages, 250 KiB

Open AccessArticle

Construction of the Pilot Free Trade Zone and Chinese Green Total Factor Energy Efficiency

by Haikuo Zhang and Chaobo Zhou

Sustainability 2023, 15(12), 9830; https://doi.org/10.3390/su15129830 - 20 Jun 2023

Cited by 1 | Viewed by 969

Abstract

In the context of China’s “double carbon” target, paying attention to regional green total factor energy efficiency (GTFEE) is crucial for ensuring a fundamental guarantee for China’s free trade zones for the promotion of sustainable development in China’s free trade zones. However, the [...] Read more.

In the context of China’s “double carbon” target, paying attention to regional green total factor energy efficiency (GTFEE) is crucial for ensuring a fundamental guarantee for China’s free trade zones for the promotion of sustainable development in China’s free trade zones. However, the existing literature lacks focus on the environmental effects of these zones. This study takes advantage of the pilot free trade zone (PFTZ) implemented in 2013 as a natural experiment, utilizing panel data from 2009 to 2020 for Chinese prefecture-level cities. It adopted a progressive difference-in-difference model to assess the effect of the PFTZ on GTFEE. The findings demonstrate a remarkable improvement in GTFEE due to the PFTZ, which remains robust even after conducting robustness checks, including the parallel trend test. The PFTZ achieves this improvement by facilitating industrial structure upgrading and promoting green technology innovation. The positive influence of the PFTZ on GTFEE is particularly prominent in coastal cities and non-resource-based cities. This study contributes to the understanding of the environmental effects of free trade zones, providing a direct response to the key question of whether the free trade zone policy can effectively support high-quality economic development in the new era. Moreover, it offers useful policy implications for advancing further openness, winning the battle against pollution, and boosting high-quality economic development. Full article

(This article belongs to the Special Issue Energy Transitions and Green Finance towards Sustainability)

23 pages, 610 KiB

Open AccessArticle

Too Much of a Good Thing? The Impact of Serial M&A on Innovation Performance

by Xiaoxu Zhang, Yu Song and Hongyu Liu

Sustainability 2023, 15(12), 9829; https://doi.org/10.3390/su15129829 - 20 Jun 2023

Viewed by 1035

Abstract

Based on the sample of serial M&A of Chinese listed companies from 2010–2019, this paper intends to investigate the impact of serial M&A on innovation performance and the impact of financing constraints and digital inclusive finance (DIF). The empirical results show that an [...] Read more.

Based on the sample of serial M&A of Chinese listed companies from 2010–2019, this paper intends to investigate the impact of serial M&A on innovation performance and the impact of financing constraints and digital inclusive finance (DIF). The empirical results show that an inverted U-shaped relationship exists between serial M&A and innovation performance that first goes up and then goes down. The results of mechanism analysis show that financing constraints play a mediating role in the inverted U-shaped relationship between serial M&A and innovation performance, while DIF plays a moderating role in the mediating effect of serial M&A on innovation performance through the financing constraint. The heterogeneity analysis finds that the inverted U-shaped relationship between serial M&A and innovation performance is more significant in firms with non-state ownership property, a higher business environment index, and medium and large-scale firm size. The research results not only help to promote the in-depth analysis of the impact of serial M&A on innovation performance, but also help to provide targeted theoretical reference and practical guidance for corporate management decision making. Full article

(This article belongs to the Section Economic and Business Aspects of Sustainability)

► Show Figures

Figure 1

18 pages, 2306 KiB

Open AccessReview

Green Supply Chains and Digital Supply Chains: Identifying Overlapping Areas

by Viviana D’Angelo and Valeria Belvedere

Sustainability 2023, 15(12), 9828; https://doi.org/10.3390/su15129828 - 20 Jun 2023

Cited by 3 | Viewed by 1522

Abstract

This article explores the overlapping between green supply chains and digital supply chains through a bibliometric analysis of the two scientific domains. Using articles’ bibliographic data, we conducted a bibliometric analysis of the literature on green supply chains and digital supply chains to [...] Read more.

This article explores the overlapping between green supply chains and digital supply chains through a bibliometric analysis of the two scientific domains. Using articles’ bibliographic data, we conducted a bibliometric analysis of the literature on green supply chains and digital supply chains to examine the intellectual structure of these research domains. By analyzing 131 studies belonging to five different clusters where digital supply chains and green supply chains overlap, our results reveal different overlapping intensity in the different clusters identified. These results reveal also grey areas in the academic research on green and digital supply chains and they may inspire further research explorations, such as addressing whether and how this approach could produce benefits for companies in terms of environmental and operational performance. Full article

(This article belongs to the Special Issue Analysis and Optimisation of Operations and Supply Chain Management: An Industry 5.0 Perspective)

► Show Figures

Figure 1

18 pages, 3767 KiB

Open AccessArticle

A Study on the Effect of Innovation-Driven Policies on Industrial Pollution Reduction: Evidence from 276 Cities in China

by Qingwei Shi, Yupeng Hu and Tiecheng Yan

Sustainability 2023, 15(12), 9827; https://doi.org/10.3390/su15129827 - 20 Jun 2023

Cited by 2 | Viewed by 1159

Abstract

The societal effects of industrial pollution have spurred heated debates, but more research into the influence and internal mechanism of innovative pilot city policies (IPCPs) on industrial emissions is needed. Using panel data from 276 Chinese cities between 2004 and 2018, the study [...] Read more.

The societal effects of industrial pollution have spurred heated debates, but more research into the influence and internal mechanism of innovative pilot city policies (IPCPs) on industrial emissions is needed. Using panel data from 276 Chinese cities between 2004 and 2018, the study employs a multi-period difference-in-differences model to explore the effects and mechanisms of pilot policies on industrial SO₂ emissions, with a specific focus on how they can be mitigated by innovative techniques. The results indicate that (1) the Chinese innovative pilot city policies (CIPCPs) significantly reduced emissions in urban areas; (2) the concentration of talent, innovation policy, venture capital, and technology plays a pivotal role; and (3) the SO₂ reduction effects are more pronounced in larger cities, such as super-large, mega-, and first-tier cities in the southeast, and in cities with a high market potential. This study provides empirical evidence to support the promotion of sustainable economic and social development, the resolution of environmental pollution problems, and the enhancement of public health. Full article

► Show Figures

Figure 1

18 pages, 3716 KiB

Open AccessArticle

Evaluation the Performance of Three Types of Two-Source Evapotranspiration Models in Urban Woodland Areas

by Han Chen, Ziqi Zhou, Han Li, Yizhao Wei, Jinhui (Jeanne) Huang, Hong Liang and Weimin Wang

Sustainability 2023, 15(12), 9826; https://doi.org/10.3390/su15129826 - 20 Jun 2023

Viewed by 1010

Abstract

The determination of the evapotranspiration (ET) and its components in urban woodlands is crucial to mitigate the urban heat island effect and improve sustainable urban development. However, accurately estimating ET in urban areas is more difficult and challenging due to the heterogeneity of [...] Read more.

The determination of the evapotranspiration (ET) and its components in urban woodlands is crucial to mitigate the urban heat island effect and improve sustainable urban development. However, accurately estimating ET in urban areas is more difficult and challenging due to the heterogeneity of the underlying surface and the impact of human activities. In this study, we compared the performance of three types of classic two-source ET models on urban woodlands in Shenzhen, China. The three ET models include a pure physical and process-based ET model (Shuttleworth–Wallace model), a semi-empirical and physical process-based ET model (FAO dual-K_c model), and a purely statistical and process-based ET model (deep neural network). The performance of the three models was validated using an eddy correlation and stable hydrogen and oxygen isotope observations. The verification results suggested that the Shuttleworth–Wallace model achieved the best performance in the ET simulation at main urban area site (coefficient of determination (R²) of 0.75). The FAO-56 dual K_c model performed best in the ET simulation at the suburb area site (R² of 0.77). The deep neural network could better capture the nonlinear relationship between ET and various environmental variables and achieved the best simulation performance in both of the main urban and suburb sites (R² of 0.73 for the main urban and suburb sites, respectively). A correlation analysis showed that the simulation of urban ET is most sensitive to temperature and least sensitive to wind speed. This study further analyzed the causes for the varying performance of the three classic ET models from the model mechanism. The results of the study are of great significance for urban temperature cooling and sustainable urban development. Full article

(This article belongs to the Special Issue Hydrological Management Adopted to Climate Change)

► Show Figures

Figure 1

20 pages, 4271 KiB

Open AccessArticle

Early Warning Evaluation and Warning Trend Analysis of the Resource and Environment Carrying Capacity in Altay Prefecture, Xinjiang

by Shengxin Lan, Xiaona Wang, Meifang Li, Xiaohua Fu, Mei Xu, Jian Zhu, Ping Wang, Yu Mao, Zuoji Dong, Jiahui Li, Lanfang Cao and Zhiming Liu

Sustainability 2023, 15(12), 9825; https://doi.org/10.3390/su15129825 - 20 Jun 2023

Viewed by 898

Abstract

Ecologically fragile areas in China account for more than half of its land area. Performing early warning assessments and trend analyses of resource and environment carrying capacity in ecologically fragile areas can lay a scientific foundation for ecological conservation in the areas. Based [...] Read more.

Ecologically fragile areas in China account for more than half of its land area. Performing early warning assessments and trend analyses of resource and environment carrying capacity in ecologically fragile areas can lay a scientific foundation for ecological conservation in the areas. Based on the connotation of resource and environment carrying capacity, an early warning index system of resource and environment carrying capacity in Altay prefecture was constructed from the three aspects natural resource carrying capacity, eco-environment carrying capacity, and economic and social support capacity. The grey relational projection method model was used to analyze the current alarm situation of the resource and environment carrying capacity in Altay prefecture from 2011 to 2020, and then the back propagation (BP) neural network and a mathematical statistics software were used to predict the evolution of the alarm situation of the resource and environment carrying capacity in Altay prefecture from 2021 to 2025. The results demonstrated that (1) the natural resource carrying capacity subsystem was the main system of the development of the resource and environment carrying capacity in Altay prefecture, and its impact on the resource and environment carrying capacity in Altay prefecture was greater than the eco-environment carrying capacity and economic and social support capacity; (2) the resource and environmental carrying capacity of Altay prefecture showed a slight upward trend from 2011 to 2020, although the range was constrained and the level of warning remained “moderate warning”. A spatial pattern of “weak in the middle, strong in the two poles” was exhibited by the warning scenario about the carrying capacity of each county and city. Except for the warning of Habahe County and Qinghe County, where the warning was slightly worse than that in 2020, the warning of resource and environment carrying capacity in Altay prefecture and other counties and cities would show a trend of fluctuation and decline from 2021 to 2025. However, the degree of alarm did not change substantially and remained at the level of “moderate warning”; (3) the main factors restricting the mitigation of the warning of resource and environment carrying capacity in Altay prefecture included a low soil fertility index, a small total reservoir capacity, low per capita mineral resource reserves, a low water resource development and utilization rate, a low comprehensive utilization rate of industrial solid waste, and a low land output rate. Full article

(This article belongs to the Topic Novel Advanced Oxidation Processes for Wastewater Treatment)

► Show Figures

Figure 1

15 pages, 4460 KiB

Open AccessArticle

Effects of Metal Waste Strips on Strength Characteristics of Road Base Material

by Osama Ragab Ibrahim, Mazoun Al Sinani, Israa Al Sinani, Bayan Al Shibli, Amjaad Al Badi and Salma Al Maghawry

Sustainability 2023, 15(12), 9824; https://doi.org/10.3390/su15129824 - 20 Jun 2023

Viewed by 1024

Abstract

Metal manufacturing produces various types of byproducts and metal waste that have been growing exponentially. The increasing amounts of metal waste are usually disposed of in landfills, which causes soil and water pollution and increases the amount of gas emissions. On the other [...] Read more.

Metal manufacturing produces various types of byproducts and metal waste that have been growing exponentially. The increasing amounts of metal waste are usually disposed of in landfills, which causes soil and water pollution and increases the amount of gas emissions. On the other hand, in the field of pavement construction, the demand for natural materials is increasing rather rapidly. Many studies have suggested utilizing aggregate-like waste material in pavement construction, but there is little to no literature documenting the use of metal strips of different types. The aim of this study is to investigate utilizing the metal waste produced by the Intag Sohar company in layers of flexible pavement. Selected types of metal waste were utilized in the construction of the material used for base and subbase road layers. Three main parameters were studied: the number of layers, the distance between strips, and the direction of the strips. The effect of the metal waste on the pavement material is evaluated using the standard California Bearing Ratio test (CBR), which is the most important indication of the strength of the pavement material. Results show that the highest-quality mix consisted of four layers of metal waste with 1 cm spacing in one direction with CBR% values equal to 118.807%. Full article

(This article belongs to the Section Environmental Sustainability and Applications)

► Show Figures

Figure 1

13 pages, 1058 KiB

Open AccessArticle

Research on Government Regulations, Cognition and Farmers’ Willingness of Straw-to-Field

by Hong Chen, Haoyan Wang and Yanqiu Li

Sustainability 2023, 15(12), 9823; https://doi.org/10.3390/su15129823 - 20 Jun 2023

Cited by 2 | Viewed by 1008

Abstract

Contemporarily, the promotion and application of straw-to-field technology plays an important role in developing high-quality green agriculture, alleviating agricultural non-point source pollution and realizing the double carbon target. As the main subject of straw-to-field, a farmers’ willingness directly determines their straw-to-field behavior. To [...] Read more.

Contemporarily, the promotion and application of straw-to-field technology plays an important role in developing high-quality green agriculture, alleviating agricultural non-point source pollution and realizing the double carbon target. As the main subject of straw-to-field, a farmers’ willingness directly determines their straw-to-field behavior. To explore the influencing factors of farmers’ straw-to-field willingness and to improve the comprehensive utilization level of straw, this paper researches the relationship between government regulation, farmers’ subject cognition and straw-to-field willingness based on the survey data of 733 farmers in Heilongjiang province, and it examines the mediating role of farmers’ cognition in the process of government regulation affecting farmers’ willingness of straw-to-field. The results evidence that policy incentives and administrative constraints affect farmers’ willingness of straw-to-field by influencing ecological and technical cognition. However, farmers’ cognition of the cost and benefit of straw-to-field is biased; thus, this factor cannot effectively transform the willingness of straw-to-field into action. Full article

► Show Figures

Figure 1

17 pages, 5152 KiB

Open AccessArticle

Bituminous Coal Sorption Characteristics and Its Modeling of the Main Coal Seam Gas Component in the Huaibei Coalfield, China

by Gang Wu, Zhiwei Ye, Lei Zhang and Jun Tang

Sustainability 2023, 15(12), 9822; https://doi.org/10.3390/su15129822 - 20 Jun 2023

Cited by 1 | Viewed by 817

Abstract

Knowledge of the gas sorption and permeability characteristics of a coal provides an essential basis for the evaluation of coalbed methane reserves and their recoverability. Thus, the gas excess sorption capacities of the main gas component of coal seam gas (CSG) in bituminous [...] Read more.

Knowledge of the gas sorption and permeability characteristics of a coal provides an essential basis for the evaluation of coalbed methane reserves and their recoverability. Thus, the gas excess sorption capacities of the main gas component of coal seam gas (CSG) in bituminous coal samples derived from the Xutuan Coal Mine in the Huaibei Coalfield, in the Anhui Province of China, were measured using a volumetric method. The results showed that under the same equilibrium pressure, the order of excess sorption capacity was CO₂ > CH₄ > N₂. Furthermore, the sorption capacity ratios of coal from the Xutuan Mine for CO₂, CH₄, and N₂ were approximately 6.0:2.3:1. It was also demonstrated that the sorption capacity during depressurization was always larger than that of the adsorption process, which is indicative of desorption hysteresis. The behaviors of three adsorption models, Langmuir, BET, and D-R, all of which include two parameters, are considered in this paper. The different gas sorption measurement data were fitted by the three models. For the bituminous coal samples, the fits of the D-R equation of all three different gases are higher than 0.99, the fits of the Langmuir equation are higher than 0.985, while the fits of the BET equation for CH₄ and N₂ absorption are higher than 0.95. However, the fits of the BET equation for CO₂ absorption are only about 0.5. Coal sorption has an apparent influence on coal permeability; the permeability of the same coal sample to N2, CH₄, and CO₂ gases was tested and analyzed. The result shows that the permeability of CO₂ was found to be lower than that of other coal seam gas constituents, CH₄ and N₂, due to their different adsorption abilities. Full article

(This article belongs to the Collection Sustainable Development of Coal Based Energy: Technology, Environment, Humanities, Economy, and Education)

► Show Figures

Figure 1

20 pages, 2549 KiB

Open AccessArticle

Research on Sustainable High-Quality Forestry Development in China—From Measurements, Dynamic Evolution, and Regional Differences

by Yu Jiang and Shihao Zhang

Sustainability 2023, 15(12), 9821; https://doi.org/10.3390/su15129821 - 20 Jun 2023

Viewed by 936

Abstract

Following the new development philosophy, this research elaborates the connotation of sustainable high-quality forestry development and constructs an evaluation index system based on the connotation. The entropy-based TOPSIS method was used to measure the forestry development level from 2005 to 2021 in China. [...] Read more.

Following the new development philosophy, this research elaborates the connotation of sustainable high-quality forestry development and constructs an evaluation index system based on the connotation. The entropy-based TOPSIS method was used to measure the forestry development level from 2005 to 2021 in China. On this basis, the kernel density estimation, spatial association analysis, Markov chain, and Gini index were used to analyze the evolution characteristics in time and space and regional differences in China’s forestry development from multiple angles and levels. The results show that, first, although the overall sustainable high-quality development level of China’s forestry tends to rise, and the level ranking of each province is relatively stable, the development level varies greatly from province to province; second, the development level in the central, eastern, and western regions shows an upward trend, and in the northeast region, it rose first and then fell, presenting a decreasing step distribution of from the eastern, central, northeast, to western regions; third, the regional differences are the main reasons for the development difference in China’s forestry, with the largest difference in the east, followed by the west, central, and northeast regions; fourth, sustainable high-quality forestry development in various provinces has a great effect in terms of spatial agglomeration, and the spatial lag has a significant impact on the transfer of sustainable high-quality forestry development; however, there are still some difficulties in achieving progress in its development. Full article

► Show Figures

Figure 1

Journal Menu

Journal Browser

Sustainability, Volume 15, Issue 12 (June-2 2023) – 711 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI