Environmental Problems Research Articles

Experimental Study on Direct Shear Behavior of New-to-Old Interface for Recycled Aggregate Concrete with Different Replacement Ratios

The large amount of construction waste produced by the construction industry brings severe natural resource consumption and environmental pollution, elevating the awareness of sustainable development. Recycled aggregate concrete, crushed from construction waste, is recognized as an eco-friendly material and the current optimal solution for the environmental problem. The interface shear failure between substrate recycled coarse aggregate concrete (RAC) and overlay natural aggregate concrete becomes vital for structural safety. In order to study the direct shear performance, a total of 19 specimens were designed to carry out the direct shear test with different replacement ratios, interface types and curing ages. The whole process and failure mode were recorded. The relationships between the shear capacity and deformation, ductility, damage evolution, and energy dissipation were evaluated and discussed. The results demonstrate that the RAC component in the interface was the weak line in the shear plane, accelerating the damage evolution. In the early curing stage, the replacement ratio had a slight influence on the shear properties. Increasing the recycled aggregate replacement ratio from 0 to 100% improved the normalized strength ratio by 8.94% and 14.62%, respectively, for curing ages of 3 days and 7 days. A regression equation was proposed to predict the shear strength, accounting for the curing ages. With the increase in the replacement ratio, the ductility and energy dissipation gradually enhanced.

Studying of Mechanical Behavior of Waste Materials Modified Cement Mortar

Large-scale environmental problems have been triggered by ceramic tiles from demolished buildings and animal bone waste. Therefore, optimizing their potential for reuse and recycling is an important goal of sustainable solid waste management. The primary objective of this study is to evaluate the feasibility of partial replacement of the fine aggregates in cement mortar with a combination of natural animal bone powder and industrial waste materials which is wall tiles ceramic powder. This study measures thermal and mechanical characteristics. Recycling construction waste is one of many ways to deny waste material from entering landfills and create new eco-friendly material that reduces energy consumption in buildings. Modified mortar cement specimens with 5% up to 25% mixtures were combined using a 1:3 ratio and a 0.5 W/C ratio to see how the ratios would affect the material’s properties. The addition of a superplasticizer boosted the cement mortar’s workability and compressive strength. The compressive strength, flexural strength, density, and thermal conductivity were evaluated for each mortar mixture ratio. Results showed that compared to regular cement mortar, cement mortar combined with 20% bone and ceramic powder wastes reached the optimal replacement percentage. Compressive strength increased by 54% and flexural strength by about 67%. At the 28-day mark, thermal insulation was lowered by 25%.It is concluded from this study that it is possible to use bone waste as a natural material with ceramic waste as an industrial material to modify the insulation and mechanical properties of cement mortar.

TaWRKY55-TaPLATZ2 module negatively regulate saline-alkali stress tolerance in wheat.

Saline-alkaline soils are a major environmental problem that limit plant growth and crop productivity. Plasma membrane H+-ATPases and the salt overly sensitive (SOS) signaling pathway play important roles in plant responses to saline-alkali stress. However, little is known about the functional genes and mechanisms regulating the transcription of H+-ATPases and SOS pathway genes under saline-alkali stress. In the present study, we identified that the plant AT-rich sequence and zinc-binding (TaPLATZ2) transcription factor are involved in wheat response to saline-alkali stress by directly suppressing the expression of TaHA2/TaSOS3. The knockdown of TaPLATZ2 enhances salt and alkali stress tolerance, while overexpression of TaPLATZ2 leads to salt and alkali stress sensitivity in wheat. In addition, TaWRKY55 directly upregulated the expression of TaPLATZ2 during saline-alkali stress. Through knockdown and overexpression of TaWRKY55 in wheat, TaWRKY55 was shown to negatively modulate salt and alkali stress tolerance. Genetic analyses confirmed that TaPLATZ2 functions downstream of TaWRKY55 in response to salt and alkaline stresses. These findings provide a TaWRKY55-TaPLATZ2-TaHA2/TaSOS3 regulatory module that regulates wheat responses to saline-alkali stress.

Recent Progress on Organic Electron Donors (OEDs) Enabled Radical Reactions

Over the past few decades, organic transformations facilitated by small organic molecules have witnessed considerable advancements. Small organic molecules have been widely applied to the construction of various skeletons. However, reduction as one of the fundamental reactions is generally initiated by metal‐containing reducing agents, although the initial progress of organic electron donors (OEDs) enabled reductive cleavage of some chemical bonds had been achieved in 1990s. Due to their structural diversity and tunability, OEDs can overcome the limitations of metal‐based reducing agents, such as low selectivity and poor functional group tolerance as well as the environmental problems caused by substantial inorganic waste after reactions. Building on a brief historical overview of OED research, this review focuses on the rencent advancements of the OEDs promoted radical reactions. It covers the reduction of C‐X (X =C, O, N etc.) single bonds, radical cyclization, intermolecular radical addition to unsaturated bonds, radical coupling, functionalization of aromatics, and C‐H bond activation. Additionally, the mechanistic insights of the typical reactions are highlighted for well understanding of the reaction mode involving OEDs.

A Study on the Charring Properties of Glued Laminated Korean Larch Timber Columns

As the carbon storage capacity of timber is recognized, there is growing interest in timber and wooden structures as a solution to various environmental problems. The use of Korean timber with substantial carbon storage capacity is required to reduce Korean carbon emissions and circulate timber resources. In this study, fire tests were conducted to investigate the charring properties of glued laminated timber columns made of Korean larch. The fire tests were conducted under both load-bearing and non-load-bearing conditions. The fire test results showed that the charring depth was affected by the corners of the section and that the load ratio had an insignificant influence on the charring depth when the load ratio was 0.9 or less. This study provides data that can be used to compare the charring properties of laminated wood produced using South Korean larch with the charring properties of foreign standards. This research provides reference data for developing fire-resistant design standards for timber structures made from South Korean timber.

Theoretical predictions of CO2, H2 and H2O adsorption mechanisms on M2C-MXene: Selectivity and potential application insights

M2C-MXenes, owing to their abundant adsorption sites, exhibit significant potential in CO2 capture, utilization, and storage (CCUS) and hydrogen energy applications, contributing to hydrogen utilization and global carbon reduction, and thus solving intractable energy and environmental problems. However, the extensive variety of M2C compounds poses challenges to the systematic evaluation of their applications in these fields. The exploration of the adsorption properties of M2Cs is a key fundamental aspect of these studies, and therefore, this study employs calculations across 456 adsorption systems to elucidate the adsorption mechanisms of 19 M2C compounds for small molecules (CO2, H2 and H2O). The results indicate that these M2C materials possess structural stability and metallic characteristics, with periodic variations in the d-band center aligning with trends in CO2 adsorption energy. Notably, molecular orientation impacts adsorption energy more significantly than adsorption sites, particularly for CO2, while M2C compounds primarily exhibit physical adsorption towards H2. Specifically, Sc2C preferentially adsorbs CO2 in atmospheric conditions, and shows chemical adsorption towards H2O, but exhibits negligible adsorption for H2; conversely, Cr2C demonstrates higher adsorption potential for H2. Both materials exhibit favorable thermodynamic stability, suggesting Sc2C is suitable for CCUS applications, while Cr2C holds promising prospects for hydrogen storage.

Resonating Between Past and Present: Long-Term History for the Island of New Guinea

The archaeology of the island of New Guinea is ancient and surprising, yet it is highly fragmentary in space and time. Consequently, archaeology provides only local and fleeting glimpses of social life in the distant past. In this review, we consider several key themes, such as initial colonization at least 55,000 years ago, the emergence of agriculture by at least 7,000–6,400 years ago, and social diversification in the last few thousand years. We build our discussions around robust archaeological records that convey a coherent impression of what people were doing in the past. We also highlight the ways in which archaeology can be repurposed to address contemporary issues, including social and environmental problems, and flag how a distinctive New Guinean archaeology could be rooted in a vegecultural conception of social life and time.

Biomass Energy from Agricultural Waste: Evaluating Groundnut Vines and Pumpkin Straws for Combustion Performance

Energy demand has risen significantly in developing countries due to rapid population growth and increase in economic activities such as industrialization, automation manufacturing and digitalization. Dependency on conventional sources of energy in both rural and peri-urban is high. Traditional energy resources lead to environmental degradation due to carbon oxide release leading global warming and deforestation which results to hydrological decline; therefore, need to come up with renewable resources from other sources such as agricultural wastes to meet the demand and solve environmental pollution problems. This study carried out an investigation on combustion and performance analysis of pumpkin straws and groundnut vines to establish their energy potential. ASTM standards were used to determine the proximate and ultimate properties. This analysis revealed moisture content (8.7-12.4%), volatile matter (63-69%), fixed carbon (11.5-18.5%), ash content (6.3-8.2%), Sulphur (0.09-0.13%), nitrogen (1.02-1.03%), oxygen (5.01-55.88%), carbon (41.8-43%) and hydrogen (5.96-6.3%). Calorific values for the briquettes were above 4389 kCal, which is above most biomass. The density and compressive strength were above 0.63 g/cm3 and 17N/mm2 respectively from compaction pressure of 150, 250 and 350 kg/cm2. The burning time was between 4 and 5.3 min, showing an increase with compaction pressure, burning rate ranged between 4.3 and 2.9 g/min, a decrease with compaction pressure increase. The specific fuel consumption portrayed an inverse relationship with calorific value and a direct relationship with compaction pressure, ranging between 166 to 176 grams per litre. Temperature-weight analysis revealed thermo stability of this feedstock, portraying resemblance to proximate analysis. Having exhibited close relationship to other agricultural wastes used for fuel, groundnut vines and pumpkin straws are a solution to environmental degradation by reducing deforestation and emissions. It is recommended that further research on mixing this feedstock with other agricultural wastes as well as making and testing of pellets be carried out to maximize energy output.

Bio-sourced tartaric acid-derived tartarimides as diol counterparts towards renewable polyurethanes

The depletion of petroleum-based fossil resources and ever-increasing environmental problems are serious issues in the production of polymeric materials. An increasingly important approach is to obtain the building blocks used in the production of these materials from renewable sources of natural origin. In the present study, bio-sourced tartaric acid-based tartarimides were evaluated as monomeric diol compounds to synthesize polyurethane polymers. Structurally diverse tartarimides were conveniently obtained from the condensation reactions of tartaric acid with various primary amine compounds. The diol structure of the generated tartarimides allowed to access polyurethanes along with the polymerizations of diisocyanate monomers. Copolymers in the range of 22.9 kDa to 29.3 kDa molecular weights were obtained with moderately high total monomer conversions (up to 96%). Depending on the tartarimide and diisocyanate monomers employed during polymerization, copolymers with different physical and thermal properties were generated. By utilizing tartarimides carrying furan and alkene functionalities, side chain reactive polyurethanes were synthesized. These reactive polymers were evaluated in post-polymerization modification and crosslinking processes by using radical thiol-ene and Diels-Alder based click reactions. The results obtained in this study demonstrated that the bio-sourced tartarimides could provide a convenient access to structurally tailorable polyurethane polymers that are important materials in various applications.

Enhancing Algal Bloom Level Monitoring with CYGNSS and Sentinel-3 Data

Algal blooms, resulting from the overgrowth of algal plankton in water bodies, pose significant environmental problems and necessitate effective remote sensing methods for monitoring. In recent years, Global Navigation Satellite System–Reflectometry (GNSS-R) has rapidly advanced and made notable contributions to many surface observation fields, providing new means for identifying algal blooms. Additionally, meteorological parameters such as temperature and wind speed, key factors in the occurrence of algal blooms, can aid in their identification. This paper utilized Cyclone GNSS (CYGNSS) data, Sentinel-3 OLCI data, and ECMWF Re-Analysis-5 meteorological data to retrieve Chlorophyll-a values. Machine learning algorithms were then employed to classify algal blooms for early warning based on Chlorophyll-a concentration. Experiments and validations were conducted from May 2023 to September 2023 in the Hongze Lake region of China. The results indicate that classification and early warning of algal blooms based on CYGNSS data produced reliable results. The ability of CYGNSS data to accurately reflect the severity of algal blooms opens new avenues for environmental monitoring and management.

Sustainability requires the integration of farmer knowledge, scientific advancements, and comprehensive innovation.

This viewpoint paper emphasises the need to diversify food production methods to simultaneously combat hunger and reduce environmental problems. The recommendations of the UN Food System Summit 2021 relate primarily to (i) the conservation of natural ecosystems, (ii) the sustainable management of existing agricultural land while increasing productivity and (iii) the restoration of already degraded land. Europe in particular faces unique challenges, such as reducing pollution and promoting organic farming up to 25 percent of the agricultural land area while maintaining food production. Ongoing efforts aim to create a transparent, fair and multi-level regulatory framework to support the Green Deal. The implementation of the Corporate Sustainability Reporting Directive (CSRD), which will sooner or later affect a larger proportion of European farmers, should support the transition. Science and innovation play a central role in this, as they are the cornerstones on which sustainable food systems are built. It is imperative that farmers actively participate in the co-design processes and utilise their wealth of experience and creativity to drive these innovations forward. A crucial aspect of the transition to sustainability is changing consumption patterns to limit food waste and reduce meat consumption. While this transition is essential, it is not without its formidable challenges. Diversification of agriculture, encompassing a spectrum of established techniques, is touted as a promising approach to achieving sustainability without sacrificing productivity. Furthermore, integrating truly sustainable agricultural practices with cutting-edge innovations, including new genomic techniques, has the potential to be a transformative solution.

Interannual moisture variability on the Qinghai Plateau: Trends, patterns, and implications

Investigating surface dry-wet patterns on the Qinghai Plateau (QP) is crucial for water allocation, ecological sustainability, and climate variability adaptation strategies. Existing discrepancies in the QP dry-wet trends and distribution characteristics underscored the need for a more refined analysis. This study utilized the Thornthwaite Moisture Index (IM) to quantify changes in surface dryness and wetness under prevailing climatic conditions. Linear trend regression and ensemble empirical mode decomposition (EEMD) were applied to study the dynamic and periodic characteristics of the QP from 1980 to 2018.Our findings revealed a decrease from southeast to northwest in IM, with the semi-arid and sub-humid transition line aligning closely with the 400 mm isohyet. The dry-wet transition line exhibited a northwestward trend over the past four decades. Possibly influenced by monsoon circulation and El Niño-Southern Oscillation (ENSO), the annual IM displayed a quasi-cycle of 3 to 5 years, manifested by a dry period (1990–2004) and a wet period (2005–2012). However, spatial differences existed, challenging the universality of the “Dry gets Drier and Wet gets Wetter (DDWW)” pattern. Precipitation (PRCP) changes could predict over 90 % of IM spatiotemporal variations. Additionally, the IM response to Average Temperature (TAVG) exhibited an inverted U-shaped curve, with a boundary (−3.8 °C) below which cooler regions became wetter and above which they became drier. The observed warming and precipitation shifts suggested that continued warming could lead to warmer and wetter climates, potentially causing ecological and environmental problems. Therefore, examining the surface moisture budget is of critical scientific and practical significance, in order to provide a decision-making basis for mitigating and adapting to climate change.

Biotechnology in Food Packaging Using Bacterial Cellulose.

Food packaging, which is typically made of paper/cardboard, glass, metal, and plastic, is essential for protecting and preserving food. However, the impact of conventional food packaging and especially the predominant use of plastics, due to their versatility and low cost, bring serious environmental and health problems such as pollution by micro and nanoplastics. In response to these challenges, biotechnology emerges as a new way for improving packaging by providing biopolymers as sustainable alternatives. In this context, bacterial cellulose (BC), a biodegradable and biocompatible material produced by bacteria, stands out for its mechanical resistance, food preservation capacity, and rapid degradation and is a promising solution for replacing plastics. However, despite its advantages, large-scale application still encounters technical and economic challenges. These include high costs compared to when conventional materials are used, difficulties in standardizing membrane production through microbial methods, and challenges in optimizing cultivation and production processes, so further studies are necessary to ensure food safety and industrial viability. Thus, this review provides an overview of the impacts of conventional packaging. It discusses the development of biodegradable packaging, highlighting BC as a promising biopolymer. Additionally, it explores biotechnological techniques for the development of innovative packaging through structural modifications of BC, as well as ways to optimize its production process. The study also emphasizes the importance of these solutions in promoting a circular economy within the food industry and reducing its environmental impact.

Possibilities of Using Environmental Knowledge in the Process of Environmental Protection

Abstract In the globalising world, scientific and technical progress, increase in production areas, industrial and economic development have positively affected society and human life, but have caused serious deterioration of the ecological balance. Every person working in any field should have ecological culture and ecological knowledge. Since chemistry is mostly related to ecology among the subjects taught, the role of chemical production and anthropogenic effects in disrupting the ecological balance is great. In chemistry teaching, importance should be given to providing students with the necessary knowledge and skills about the source of environmental problems, environmental concepts, causes of problems and ways to eliminate them.

Exogenous 5-aminolevulinic acid enhanced saline-alkali tolerance in pepper seedlings by regulating photosynthesis, oxidative damage, and glutathione metabolism.

A plant growth regulator, 5-aminolevulinic acid, enhanced the saline-alkali tolerance via photosynthetic, oxidative-reduction, and glutathione metabolism pathways in pepper seedlings. Saline-alkali stress is a prominent environmental problem, hindering growth and development of pepper. 5-Aminolevulinic acid (ALA) application effectively improves plant growth status under various abiotic stresses. Here, we evaluated morphological, physiological, and transcriptomic differences in saline-alkali-stressed pepper seedlings after ALA application to explore the impact of ALA on saline-alkali stress. The results indicated that saline-alkali stress inhibited plant growth, decreased biomass and photosynthesis, altered the osmolyte content and antioxidant system, and increased reactive oxygen species (ROS) accumulation and proline content in pepper seedlings. Conversely, the application of exogenous ALA alleviated this damage by increasing the photosynthetic rate, osmolyte content, antioxidant enzyme activity, and antioxidants, including superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase, and reducing glutathione to reduce ROS accumulation and malonaldehyde content. Moreover, the transcriptomic analysis revealed the differentially expressed genes were mainly associated with photosynthesis, oxidation-reduction process, and glutathione metabolism in saline-alkali stress + ALA treatment compared to saline-alkali treatment. Among them, the change in expression level in CaGST, CaGR, and CaGPX was close to the variation of corresponding enzyme activity. Collectively, our findings revealed the alleviating effect of ALA on saline-alkali stress in pepper seedlings, broadening the application of ALA and providing a feasible strategy for utilize saline-alkali soil.

"Eat up. Save Earth." Alternative proteins and the myth of inevitable sustainability

The emerging agri-food tech sector promises to solve myriad environmental problems. This article considers the sociotechnical imaginaries that animate these claims. We focus on plant-based meat and dairy substitutes, or 'alternative proteins' (APs). To examine how APs are constructed as environmental solutions, we analyzed marketing materials, sustainability reports, and interviews. Our study illustrates how environmental metrics (Life Cycle Assessments) and corporate marketing make environmental issues legible to agri-industrial logics by reducing them to a narrow, technical issue: inefficient livestock. To critique this problem closure, we develop the concept of inevitable sustainability–where the increased adoption of a technology is equated with the assured reduction of environmental harm. We caution that APs support a neoliberal model of environmental governance that propagates apolitical and deterritorialized solutions. To reflect on the limits of agri food tech environmental fixes, we discuss three myths surrounding inevitable sustainability. We outline this concept's applicability to similar instances of environmental solutionism in agri-food tech and beyond.

Sustainable Waste Management in Urban Area - A Case Study of the Waste Management of the Cities in China

As urbanisation continues to accelerate, the integration of regional waste treatment capacity is becoming increasingly important and challenging nowadays, as economic development imbalances and environmental problems are becoming more prominent. An important component of urban development is the generation and management of municipal solid waste , and due to differences in socio-economic status, China's world-class metropolises such as Shanghai and medium-sized cities such as Xiamen are facing the same problem. This study attempts to explore the possibilities and prospects for sustainable waste management in China's future by comparing Xiamen with Shanghai, using relevant structural models and relevant research data within the city and the region. The introduction of the concept of waste-free cities also provides a greater diversity of options for future programmes. Finding effective strategies based on China's socio-economic and cultural conditions has implications for developing countries such as China in promoting the shift from waste management to a circular economy.

Management and Performance Analysis of Textile Effluent Treatment Plants in Laundries of The Local Productive Arrangement of Pernambuco

Objective: The present study aimed to assess 10 laundries for compliance with Brazilian legislation Theoretical Framework: The Local Productive Arrangement (APL) of Pernambuco plays a crucial role in job creation and economic growth in the state. However, the jeans beneficiation process consumes a significant amount of water and involves the use of various chemicals, which generate effluents with high organic loads, color, and toxicity. This has caused serious environmental problems. The issue is exacerbated during prolonged drought periods and by intermittent river flows, which reduce the natural self-purification capacity of the rivers. Method: A total of 334 influent and effluent samples were collected. All the laundries studied employed physicochemical treatment processes (flocculation followed by sedimentation). Results and Discussion: The WWTPs proved to be efficient in the removal of settleable solids, demonstrating that the coagulation and flocculation processes are effective for this purpose, even in scenarios with management deficiencies. On the other hand, poor operation of the treatment plants has resulted in other parameters, such as pH, oils, and greases, being out of compliance with current legislation. The efficiency in reducing BOD was highly inconsistent, with fluctuations ranging from over 90% efficiency to negative values, indicating significant operational issues. High concentrations of organic matter can compromise oxygen levels in the receiving bodies. It is essential to intensify monitoring and improve treatment processes to mitigate negative environmental impacts.

Twirl Store: pioneering sustainable textile practices by closing the loop

Learning outcomes After completion of the case study, the students will be able to make strategic decisions for social entrepreneurship and carry out a sustainability and social impact analysis, assess the benefits of a circular economy-based retail model and investigate ways to preserve these benefits and recognize the ethical and sustainable issues facing the fast fashion sector and how social enterprises are addressing them. Case overview/synopsis The culture of fast fashion had proven to be dangerous for the environment as it had promoted a culture of consumerism and materialism. It had also increased the landfills in different countries. The need of the hour was to upcycle used and unwanted clothes into new innovative items. This idea had been practically implemented by Mrs Sujata Chatterjee of the Twirl Store, the protagonist of this case study. Chatterjee was a social entrepreneur who recognized the environmental and social problems caused by rapid fashion and abandoned apparel in landfills. She launched the Twirl Store, a social enterprise with the mission of advancing circular economy and sustainability practices in the textile sector. Rural women were economically and culturally empowered by the enterprise’s upcycling of used clothing using their abilities, and a sustainable source of income was created. Finding abandoned clothing, sorting and processing it effectively and locating clients who share her commitment to sustainability were difficult tasks for Chatterjee. Despite the difficulties, the Twirl Store served as an example of how circular economy concepts, cultural sustainability and women’s empowerment might be combined, highlighting the importance of social entrepreneurship in addressing global concerns and fostering positive social effects and economic impact. Complexity academic level This case study is applicable for undergraduate as well as post graduate students of management studies. Supplementary materials Teaching notes are available for educators only. Subject code CSS 3: Entrepreneurship.

The Implementation and Implications of Sustainable Development Goals at City Scale and Sustainable Urban Development Path

Cities were products of human social development, but the environmental pollution problems brought by high-density buildings and high-density populations in cities had become increasingly serious. The 17 Sustainable Development Goals proposed by the United Nations in 2015 were closely related to urban sustainable development issues. Based on it, this article analyzed the impact of SDGs and related theories on urban sustainable development and possible development directions. Starting from the impact of SDGs on urban sustainable development, elaborated on their impact on already implemented urban sustainable projects and relevant theories. It concluded that the future development of sustainable cities should be based on existing cities, with different focuses on developed and developing countries, but both require the protection of historical value landscapes and the greening of existing facilities. By explaining the theories and practical cases related to SDGs and sustainable cities, hoping to provide a reference and guidance for the path of urban sustainable development.