Search Results (1,522)

The utilization of knowledge management (KM) assists construction companies in planning for waste management. This study applies KM in the material recovery of a public sector building renovation, focusing on aluminum composite panels (ACPs). The cost/benefit analysis (CBA) method examines suitable scenarios, where costs and benefits cover economic, environmental, and social perspectives. The cost/benefit (C/B) ratios reveal that the repurposing scenario, where ACP waste is repurposed as signboards, is the most suitable scenario, with a C/B of 0.96. The refurbishing scenario, in which ACP waste is refurbished as new facades, may be considered if the labor cost could be reduced through training. The repurposing scenario is further examined with a sensitivity analysis and the Leadership in Energy and Environmental Design certification, and it is found that implementing this scenario serves as a beginning step toward green certification and aligns with Thailand’s national strategies for green building promotion and the long-term Net Zero 2065 target. The study results serve as a guideline for Thailand’s transition toward a low-carbon and resource-efficient construction sector. Future studies are recommended to examine the complex relationships between costs and benefits and to track dynamic changes in the C/B ratio over time. Full article

Catalysis plays a pivotal role in green chemistry practices, particularly in reducing waste generated during chemical synthesis. Decatungstate (DT) emerges as a potent photocatalyst for Type I oxidations, exhibiting remarkable resilience to oxygen quenching, a characteristic that sets it apart from other excited triplet state photocatalysts. While homogeneous DT catalysis demonstrates effectiveness, its solubility poses challenges for its separation and recycling. To address these limitations, we focus on the development and comparison of heterogeneous DT photocatalysts, aiming to optimize their yield, recovery, and reusability. We synthesized tetrabutylammonium decatungstate (TBADT)-supported catalysts using silica, alumina, titanium dioxide, and glass wool and characterized them using diffuse reflectance measurements. Subsequently, we evaluated their photocatalytic performance by monitoring the oxidation of 1-phenylethanol and cyclohexanol under UVA irradiation. Our findings reveal that TBADT@silica emerges as the most effective catalyst, achieving approximately 20% conversion of cyclohexanol and 50% conversion of 1-phenylethanol with good reusability. Interestingly, we observed that 3-aminopropyl-triethoxysilane (APTES) treatment, intended to enhance DT anchoring, unexpectedly quenches the ³DT* triplet state, reducing catalytic activity. This unexpected finding underscores the importance of careful consideration in designing robust and recyclable heterogeneous decatungstate catalysts. Our research contributes significantly to the advancement of heterogeneous photocatalysis, paving the way for future applications in flow photochemistry. Further, we share a Python code (Google 3.12.11) to correct spectra obtained in Cary spectrometers. Full article

The growing demand for sustainable biorefinery approaches calls for efficient, environmentally benign strategies to valorize agricultural residues and ensure their complete utilization. This study explores the combination of deep eutectic solvents (DESs) and microwave heating technology as a greener process for the selective fractionation of agri-food waste residues in a zero-waste perspective. Within this framework, five representative biomasses were thoroughly investigated, namely brewer’s spent grain, raw and parboiled rice husks, rapeseed cakes, and hemp hurds. DES formulation was selected for its ability to solubilize and separate lignocellulosic components, enabling the recovery of a polysaccharide-rich fraction, lignin, and bioactive compounds. DES extraction was performed using both microwave heating and conventional batch heating, enabling a direct comparison of the two methods, the optimization of a more sustainable fractionation process, and the maximization of yields while preserving the functional integrity of the recovered fractions. A comprehensive characterization of the separated fractions was carried out, revealing that the two fractionation methods do not yield significant differences in the composition of the primary components. Moreover, a ¹³C CP-MAS NMR analysis of the recovered lignins demonstrates how this analytical technique is a real fingerprint for the biomass source. The results demonstrate the great potential of microwave DES-mediated fractionation as a mild, tunable, and sustainable alternative to conventional methods, aligning with green chemistry principles and opening new approaches for the full valorization of waste byproducts Full article

The exponential increase in global solid waste generation poses significant environmental, economic, and social challenges, particularly in rapidly urbanizing regions. Traditional waste management methods that focus on handling and disposal have proven unsustainable because of their negative impacts on air, soil, and water quality, and their contribution to greenhouse gas emissions. In response, the concept of zero-waste cities, rooted in circular economy principles, has gained increasing attention in recent years. This study proposes a comprehensive and integrated waste management system designed to optimize resource recovery across four distinct waste streams: household, healthcare, green/organic, and inert. The system integrates four specialized facilities: a Secondary Sorting Facility, Energy Recovery Facility, Composting Facility, and Inert Processing Facility, coordinated through a central Primary Sorting Hub. By enabling interconnectivity between these processing units, the system facilitates material cascading, maximizes the reuse and recycling of secondary raw materials, and supports energy recovery and circular nutrient flow. The anticipated benefits include enhanced operational efficiency, reduced environmental degradation, and generation of multiple revenue streams. However, the implementation of such a system faces challenges related to high capital investment, technological complexity, regulatory fragmentation, and low public acceptance. Overcoming these limitations will require strategic planning, stakeholder engagement, and adaptive governance. Full article

Sand disasters significantly restrict ecological restoration and the development of sustainable transport infrastructure in desert areas, and the impact of varying subgrade width and roughness caused by different types and uses of routes on the wind-sand environment is still unclear. To address this, four typical subgrade widths were studied, and wind tunnel experiments were carried out using models. Near the ground surface (at heights < 8.3 cm), a 3.5 cm wide subgrade had a greater effect on the windward wind speed compared with three other widths. The distance required for wind speed recovery on the leeward of the 3.5 cm wide subgrade was greater than that for the three other widths. The 3.5 cm wide subgrade had a larger effect range and extent on the leeward wind flow field compared with the three other widths. The distance needed for the leeward wind flow field to recover at the 3.5 cm wide subgrade was also greater than that for the three other widths. The sand transport rates for the 14, 26, and 41 cm wide subgrades were similar and showed a consistent trend. However, the sand transport rate for the 3.5 cm wide subgrade was more variable and was lower than that for the three other widths at near-ground surface heights but higher at intermediate heights. Width has a minor effect on the wind-sand environment around the subgrades compared to roughness. The research findings provide insights into the relationship between the subgrade width, roughness, and wind–sand environment, offering guidance for mitigating sand disasters along transportation routes. It provides theoretical support for optimizing transportation infrastructure design, promoting green and low-carbon construction, and promoting ecological restoration around the routes. Full article

Quantitative determination of calcium content in milk and dairy products is an important analytical task due to the great importance of this element in the human diet. Calcium determination in milk and dairy products was performed using semi-automatic complexometric titration with a webcam as a color change detector. The color changes were registered directly in turbid dairy dispersions, creating a white background. The analytical signals tested were the color component (R, G, B) read from the titration beaker images and the calculated Hue parameter. For the calcein indicator, the optimal signals are Green and Hue. For the HNB indicator, the optimal signals are Red and Hue. The developed method of titration using an RGB camera detector is characterized by excellent linearity (R² = 0.9999) and accuracy. RSD values range from 0.3 to 2.9%. Recovery values range from 105 to 113%. Examples of calcium determination in commercial products include milk, fermented products, cream, and cottage cheese. Full article

Urologic oncological surgery increasingly makes use of robotic systems to realize precise and minimally invasive resections, convent to shorter hospital stays and faster recovery times. The dexterity gains enabled through procedures such as robot-assisted (RA) prostatectomy have helped realize significant advancements in recent years. Complementing these effects via the used of hybrid tracers that illuminate surgical targets, i.e., cancerous tissue, has helped advance the surgical decision making via enhanced visualization. A well-known example is Indocyanine green (ICG)-Technetium-99m (^99mTc)-nanocolloid, a hybrid extension of the radiopharmaceutical ^99mTc-nanocolloid. These hybrid tracers provide a direct link between preoperative imaging roadmaps and intraoperative target identification, and improve efficiency, accuracy, and confidence of the urologist in procedures such as sentinel lymph node biopsy (SLNB). Receptor-targeted hybrid tracer analogues, for e.g., prostate specific membrane antigen (PSMA), are also being explored as an extension of the ongoing efforts that use radiotracers such as ^99mTc-PSMA-I&S. Together, these efforts jointly pave the way for novel techniques in intraoperative lesion localization in other urological malignancies. This narrative review discusses the potential use of hybrid tracers in robotic oncological urology, including different imaging techniques and their applications for tumor localization for prostate, bladder, and kidney cancer. Full article

The current research aims to develop a simple, sensitive, and green analytical method for the group extraction/monitoring of 19 organochlorine and organophosphorus pesticides from fruit juices using microwave radiation to assist a cloud point extraction (MW-CPE) in combination with re-extraction in hexane and GC-MS/MS detection. The main experimental factors affecting the CPE and re-extraction have been optimized. The matrix-matched calibration was performed, and the limit of quantification (LOQ) for all studied pesticides at optimized conditions ranged between 5 and 47 ng L⁻¹. When applying only 0.25 mL of hexane for re-extraction, the proposed method shows good accuracy and precision. The “greenness” of the developed MW-CPE-GC-MS/MS method was assessed using the AGREE prep software. The method has been successfully implemented in pesticide analysis in commercially available fruit juices (lemon concentrate and red apple juice). The recovery values obtained for most analytes were within the range of 71% and 114% and RSD below 20% (exept Heptahlor, Aldrin, o,p-DDD, p,p-DDD and o,p-DDT, p,p-DDT). The developed method combines a preconcentration with a sample clean-up step due to the extraction of the pigments into the non-polar micelles during the extraction step, and deposition in the intermediate layer of MgSO₄ during the re-extraction step. Full article

Tomato aerial parts and axillary shoots represent underutilized agricultural residues with promising phytochemical potential. Despite the recognized antioxidant capacity of rutin, current literature lacks optimized, comparative studies on its extraction from distinct tomato vegetative components. This study aimed to maximize the recovery of rutin and other bioactive compounds from tomato plant biomass using green extraction techniques—microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE)—optimized through Box–Behnken design (BBD) and Response Surface Methodology (RSM). The extraction process was optimized for three key variables: temperature, solvent concentration, and plant-to-solvent ratio. Four main responses were evaluated: total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH), and rutin concentration. The highest rutin content (8614.23 mg/kg) was obtained in extracts from axillary shoots using MAE. Overall, MAE proved more efficient in recovering both primary and secondary metabolites from axillary shoots, while UAE favored the extraction of certain micronutrients and specific amino acids. Cascade extraction further improved the recovery of key compounds such as vitamin E and quinic acid. The comparative profiling of extracts revealed significant phytochemical differences between tomato aerial parts and axillary shoots, addressing a gap in the literature and underscoring the importance of optimized extraction strategies. These findings highlight tomato plant waste as a valuable source of antioxidant compounds and set the stage for future investigations into their biological activities. Full article

In this study, a green and efficient extraction methodology was developed by leveraging the unique properties of chitosan—namely its non-toxicity, biocompatibility, and adhesive nature—to enhance the recovery of bioactive ingredients from Forsythia suspensa leaves. The core mechanism involves the formation of complexes between chitosan and the target bioactive ingredients, which significantly boosts their extraction efficiency. To substantiate this mechanism, comprehensive characterization was performed using Powder X-ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), and molecular docking analyses. The results provided robust evidence of a strong interaction between chitosan and the bioactive ingredients, leading to a marked enhancement in both the stability and aqueous solubility of the target compounds. For process optimization, a multi-objective approach was implemented using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) to simultaneously maximize the extraction yields of phillyrin and forsythoside A. The algorithm identified the optimal parameters as a leaf-to-chitosan mass ratio of 10:11.75, a solid-to-liquid ratio of 1:52 g/mL, a temperature of 80 °C, and a duration of 120 min. Under these optimized conditions, the corresponding extraction yields for phillyrin and forsythoside A were 1.68 ± 0.16% and 3.23 ± 0.27%, respectively. These findings collectively indicate that chitosan-assisted extraction represents a highly promising and advanced technology for the sustainable and effective extraction of bioactive ingredients from botanical sources. Full article

The recycling of nickel–cadmium batteries poses a significant environmental challenge due to cadmium’s high biotoxicity. This study proposes a green method for recovering cadmium from cadmium oxide (CdO) using carbon (coal) in the presence of a molten binary flux (KCl:NaCl = 0.507:0.493, melting point 667 °C). The flux’s relatively low density and conductivity enable cadmium reduction beneath and through the flux layer. Brown coal (5–25 mm) served as the reductant. The reduction of cadmium from cadmium oxide with carbon (brown coal) took place in the temperature range from 667 °C to 700 °C. To enhance the process, electrovortex flows (EVF) were employed—generated by the interaction between non-uniform AC electric currents and their self-induced magnetic fields resembling conditions in a fluidised bed reactor. The graphite crucible acted as both one of the electrodes, with a graphite rod as the second electrode. As Cd and CdO are denser than both the flux and coal, the reduction proceeded below the flux layer. The flux facilitated CdO transport to the reductant, speeding up the reaction. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed the formation of metallic cadmium beneath and within the flux layer. This method demonstrates the feasibility of flux-assisted cadmium recovery without prior mixing and offers a foundation for further optimisation of sustainable battery recycling. Full article

Driven by both natural and anthropogenic factors, farmland abandonment and recultivation constitute complex and widespread global phenomena that impact the ecological environment and society. In the Inner Mongolia Yellow River Basin (IMYRB), a critical tension lies between agricultural production and ecological conservation, characterized by dynamic bidirectional transitions that hold significant implications for the harmony of human–nature relations and the advancement of ecological civilization. With the development of remote sensing, it has become possible to rapidly and accurately extract farmland changes and monitor its vegetation restoration status. However, mapping abandoned farmland presents significant challenges due to its scattered and heterogeneous distribution across diverse landscapes. Furthermore, subjectivity in questionnaire-based data collection compromises the precision of farmland abandonment monitoring. This study aims to extract crop phenological metrics, map farmland abandonment, and recultivation dynamics in the IMYRB and assess post-transition vegetation changes. We used Landsat time-series data to detect the land-use changes and vegetation responses in the IMYRB. The Farmland Abandonment and Recultivation Extraction Index (FAREI) was developed using crop phenology spectral features. Key crop-specific phenological indicators, including sprout, peak, and wilting stages, were extracted from annual MODIS NDVI data for 2020. Based on these key nodes, the Landsat data from 1999 to 2022 was employed to map farmland abandonment and recultivation. Vegetation recovery trajectories were further analyzed by the Mann–Kendall test and the Theil–Sen estimator. The results showed rewarding accuracy for farmland conversion mapping, with overall precision exceeding 79%. Driven by ecological restoration programs, rural labor migration, and soil salinization, two distinct phases of farmland abandonment were identified, 87.9 kha during 2002–2004 and 105.14 kha during 2016–2019, representing an approximate 19.6% increase. Additionally, the post-2016 surge in farmland recultivation was primarily linked to national food security policies and localized soil amelioration initiatives. Vegetation restoration trends indicate significant greening over the past two decades, with particularly significant increases observed between 2011 and 2022. In the future, more attention should be paid to the trade-off between ecological protection and food security. Overall, this study developed a novel method for monitoring farmland dynamics, offering critical insights to inform adaptive ecosystem management and advance ecological conservation and sustainable development in ecologically fragile semi-arid regions. Full article

This study investigates the hydrothermal liquefaction (HTL) of sewage sludge across a temperature range of 250–375 °C, combined with selective solvent extraction and catalytic hydrotreatment to produce high-quality biocrude. Four solvents including dichloromethane (DCM), hexane, ethyl butyrate (EB), and ethyl acetate (EA), were used to evaluate temperature-dependent extraction performance and product quality. Biocrude yields increased from 250 °C to a maximum at 350 °C for all solvents: hexane (9.3–18.1%), DCM (16.3–49.7%), EB (17.6–50.1%), and EA (9.6–23.5%). A yield decline was observed at 375 °C due to secondary cracking and gasification. Elemental analysis revealed that hexane and EB extracts had higher carbon (up to 61.6 wt%) and hydrogen contents, while DCM retained the most nitrogen (up to 3.96 wt%) due to its polarity. Sulfur remained below 0.5 wt% in all biocrudes. GC–MS analysis of 350 °C biocrudes showed fatty acids as dominant components (43–53%), especially palmitic acid, along with ketones, amides, and heterocyclic compounds. Hydrotreatment using Ni/SiO₂–Al₂O₃ significantly enhanced biocrude quality by increasing alkane content by 40–60% and reducing nitrogen levels by up to 75%, with higher heating values reaching 38–44 MJ/kg. These findings demonstrate the integrated potential of HTL process tuning, green solvent extraction, and catalytic upgrading for converting sewage sludge into cleaner, energy-dense biofuels. Full article

Aquaculture is the fastest-growing food production sector and plays a pivotal role in global food security. However, the reliance on conventional fishmeal and fish oil in aquafeeds raises sustainability concerns due to overfishing, high costs, and ecological burden. This review explores the valorisation of microalgae as a sustainable and functional alternative for aquafeed development. Microalgae are rich in proteins, polyunsaturated fatty acids, bioactive compounds, and pigments that support aquatic animal growth, immunity, and product quality. We critically examine the integration of green technologies, including cultivation systems, biomass harvesting, and eco-friendly extraction methods for optimising microalgal biomass and bioactive recovery. The review also discusses recent innovations in bioremediation and circular aquaculture systems, highlighting the role of microalgae in reducing nutrient discharge, carbon footprint, and operational cost. Challenges such as scalability, digestibility, and economic feasibility are also addressed, providing insight into pathways toward industrial adoption. This review aims to provide an updated and holistic perspective on microalgae-based aquafeeds in advancing sustainable aquaculture practices. Full article

In confronting escalating economic uncertainty, achieving a win–win situation for low-carbon transition and improved employment structure will contribute to economic recovery and sustainable growth but also contribute to building a community with a shared future for mankind. A critical issue for China’s economy and societal welfare, as well as a core component of sustainable development, concerns whether low-carbon economic transition influences employment skill structure. This study utilizes data from 30 provinces (municipalities and autonomous regions) in China from 2006 to 2021. Employing the entropy method, a low-carbon economic development level indicator system was constructed from four aspects: low-carbon output, low-carbon consumption, low-carbon resources, and low-carbon environment to measure the low-carbon economy and explore its direct and indirect effects on employment skill structure and spatial effects. The research findings indicate that low-carbon economies not only directly and significantly promote employment skill structure optimization but also indirectly generate promotional effects through pathways such as industrial structure adjustment, green innovation’s innovative effects, and factor substitution effects of increased pollution control investment. Among these, the indirect impact of industrial structure adjustment contributes most substantially. Low-carbon economies’ influence on employment skill structures exhibits spatial spillover effects, with neighboring regions’ low-carbon economies exerting positive spillover effects on local skill structures. Additionally, significant negative interdependence exists among regional employment skill structures. Based on the aforementioned research conclusions, the following recommendations are proposed: accelerate low-carbon economy development and employment skill structure enhancement in central and western regions to diminish regional disparities; encourage green innovation and promote traditional industry upgrading and transformation; formulate regional coordinated development plans, thereby strengthening the low-carbon economy’s optimizing role upon employment skills structure; and increase educational investment and strengthen labor skill training. Full article