Risk Of Environmental Pollution Research Articles

Optimization of household medical waste recycling logistics routes: Considering contamination risks.

The escalating generation of household medical waste, a byproduct of industrialization and global population growth, has rendered its transportation and logistics management a critical societal concern. This study delves into the optimization of routes for vehicles within the household medical waste logistics network, a response to the imperative of managing this waste effectively. The potential for environmental and public health hazards due to improper waste disposal is acknowledged, prompting the incorporation of contamination risk, influenced by transport duration, waste volume, and wind velocity, into the analysis. To enhance the realism of the simulation, traffic congestion is integrated into the vehicle speed function, reflecting the urban roads' variability. Subsequently, a Bi-objective mixed-integer programming model is formulated to concurrently minimize total operational costs and environmental pollution risks. The complexity inherent in the optimization problem has motivated the development of the Adaptive Hybrid Artificial Fish Swarming Algorithm with Non-Dominated Sorting (AH-NSAFSA). This algorithm employs a sophisticated approach, amalgamating congestion distance and individual ranking to discern optimal solutions from the population. It incorporates a decay function to facilitate an adaptive iterative process, enhancing the algorithm's convergence properties. Furthermore, it leverages the concept of crossover-induced elimination to preserve the genetic diversity and overall robustness of the solution set. The empirical evaluation of AH-NSAFSA is conducted using a test set derived from the Solomon dataset, demonstrating the algorithm's capability to generate feasible non-dominated solutions for household medical waste recycling path planning. Comparative analysis with the Non-dominated Sorted Artificial Fish Swarm Algorithm (NSAFSA) and Non-dominated Sorted Genetic Algorithm II (NSGA-II) across metrics such as MID, SM, NOS, and CT reveals that AH-NSAFSA excels in MID, SM, and NOS, and surpasses NSAFSA in CT, albeit slightly underperforming relative to NSGA-II. The study's holistic approach to waste recycling route planning, which integrates cost-effectiveness with pollution risk and traffic congestion considerations, offers substantial support for enterprises in formulating sustainable green development strategies. AH-NSAFSA offers an eco-efficient, holistic approach to medical waste recycling, advancing sustainable management practices.

A Novel Approach to Detecting Blockages in Sewers and Drains: The Reflected Wave Technique

Blockages in sewers and drains often result in overflows and flooding that cause significant environmental pollution and public health risks, particularly in hospitals, where the consequences can be catastrophic. Due to their low “visibility”, sewers and drains are inherently difficult to monitor and maintain, resulting in a reactive management approach whereby maintenance or repair is carried out only after a system failure has occurred. This paper investigates the feasibility of applying the reflected wave technique, a unique sonar-like monitoring approach capable of identifying changes in the geometry of closed-pipe conduits, as a means of proactive system monitoring. The technique uses a 10 Hz sinusoidal air pressure wave which is transmitted into the drainpipe. When the pressure wave encounters a system boundary, a reflection is generated which alters the measured test pressure response. Analysis of the reflections generated by a changed system boundary, such as the formation of a blockage, can provide information related to the location of that boundary within the system. An experimental setup was developed to simulate a horizontal drain using standard pipework of 100 mm diameter and 70 m length. The technique was able to detect applied blockages with cross-sectional coverage of 30% and 75%, and lengths ranging from 30 mm to 3000 mm. Accuracy was improved when the pressure sensor was positioned closer to the blockage. When the sensor was 3.4 m from the blockage, location estimates were very accurate (−2% to 3% error). At a 14 m distance from the blockage, the error increased to between 4% and 33%. The accuracy of blockage detection and location improved with increasing blockage cross-sectional area and length. Overall, the reflected wave technique could provide a potentially continuous monitoring solution for blockage detection in sewers and drains.

Chemiresistive triethylamine detection based on the novel Ti3C2Tx/Co-BDC gas sensor

Triethylamine (TEA), a representative volatile organic environmental pollutant, poses significant environmental pollution risks and can adversely affect the liver and nervous system, potentially leading to fatal outcomes. However, existing gas sensors for TEA detection have pressing drawbacks, such as safety hazards associated with high-temperature operation and poor timeliness due to time-consuming testing. Herein, the Ti3C2Tx/Co-BDC sensor demonstrates ultra-sensitive detection of TEA at a low temperature of 100 °C. This temperature is below the threshold for explosion-proof operation, ensuring safe application in flammable and explosive environments. Meanwhile, the introduction of the metal-like MXene with ultra-high conductivity accelerates the response and recovery process (11s/20s), facilitating highly efficient TEA detection within a sub-minute timeframe. The Ti-O-Co interfacial bonds between Ti3C2Tx and Co-BDC, confirmed by both XPS analysis and theoretical calculations, enhance carrier mobility across the two materials, significantly boosting gas-sensing performance. The rapid detection of TEA at low temperatures makes the Ti3C2Tx/Co-BDC sensor more suitable for practical environmental monitoring in flammable and explosive areas, further contributing to human health and production safety.

Performance Evaluation of Green Supply Chain Management in Canned Fish (Sardines) Production Unit: A Case of Indonesia

Indonesia's fishing industry, especially in East Java Province, shows great potential but also harms the environment. CV. Pasific Harvest Surabaya (CV. PHB) is a fish canning industry in Banyuwangi Regency, which is currently facing problems such as the supply of raw materials, which continues to decline; the company has not measured and planned the total consumption of energy, fuel, water and the problem of workers who have not received environmental training. Although a waste processing system is in place, the production process still carries the risk of environmental pollution. The researchers collected data through observation, interviews, literature studies, and paired comparison questionnaires. The results of the research reveal that CV. PHB manages three supply chain flows with four supply chain actors. The final performance score is 81.77, with 24 verified KPIs. The KPIs that need performance improvement are packaging time until the product is picked up by the delivery service (D4), time for handling customer complaints (R3), and environmental training for workers (E1).

Effects of liquid urea rates on nitrogen dynamics, growth, and yield of corn (Zea mays L.)

Arbitrary use of urea fertilizer reduces nitrogen use efficiency (NUE) and increases the risk of environmental pollution. An experiment was conducted at the Universiti Putra Malaysia from November 2019 to March 2020 to evaluate the application methods and rates of liquid urea (LU) on the yield performance of corn. The treatments were, U0 = control, GU100 = Granular urea (GU) 100%, LU100 = LU 100%, LU50 = LU 50% and LU33 = LU 33%, in two equal splits at 10th and 28th days after sowing (DAS) in randomized completely block design, replicates four. Results showed that plant height (206.99 cm, 216.92 cm, 214.61 cm), ear height (88.13 cm, 88.63 cm, 86.00 cm), days of maturity (88.75, 89.00, 86.75 days), number of grains per kernel row (32.25, 34.50, 33.75), fresh cob weight (10,886.60 kg ha−1, 10,946.60 kg ha−1, 10,927.93 kg ha−1) and 100-grain weight (20.51 g, 22.50 g, 21.39 g) of corn were not different significantly (p ≤ 0.05) in GU100, LU100 and LU50 treatments, respectively. The highest yield of corn was found with LU100 (6249.03 kg ha−1) treatment whereas the yield in LU50 (5666.50 kg ha−1) and GU100 (5746.64 kg ha−1) were not different significantly. Nitrogen (%) in plants was the highest in LU100 followed by LU50 treatment which was significantly higher than GU100 treatment. The total N content was also the highest in LU100 (102.83 kg ha−1) though the total N content was not different significantly in LU50 (77.62 kg ha−1) and GU100 (83.84 kg ha−1) treatments. The NUE was the highest in LU50 (66.92%) treatment followed by LU100 (51.47%) treatment. The results of the study suggested that LU was superior to GU and the LU100 was the best application rate while LU50 treatment was comparable to GU100 in corn cultivation.

Multidimensional Approach for the Assessment of Environmental Pollution and Health Risk Associated With V, Ni, Cr, Cu, and Zn in the Recent Sediments of Kabini Interstate River, Southeastern Western Ghats, India

ABSTRACTThe present work intends to study the variation of heavy metals (HMs) to scrutinize the scenario of pollution index and associated environmental risk, as well as source weathering conditions along the Kabini River. The decreasing order of concentration of HMs along the basin is Cr > V > Ni > Zn > Cu. The paper spotlights the pollution grade in sediments, assessed by the geo‐accumulation index (Igeo), contamination factor (Cf), pollution load index (PLI), and enrichment factor (Ef). The assessment of ecological risk is studied as potential ecological risk index (RI), toxic risk index (TRI), and modified hazard quotients (mHQs). As per the Igeo and Cf, V and Cr concentrations are higher in the region. Further, PLI confirmed that 35% of samples exceeded the limits of sediment quality guidelines. The RI and TRI values show that a higher ecological risk is associated with Ni, V, and Cr and with Cu and Cr, respectively. Additionally, the 23% Ni and 20% Cu samples from mHQ indicate the severity of pollution in the aquatic environment. The inputs from anthropogenic and natural sources change the concentration of these HMs along the region. Moreover, the study of CIA and plagioclase index of alteration plots confirmed the low to intense weathering conditions. The statistical approach shows the linkage between Cr–V, Cu–Zn, and principal component analysis–derived prominent sources: industrial and agricultural runoff, as well as higher silicate weathering, contribute to the HMs concentration in the region. The Kabini River passes through different climatic and land‐use domains of Kerala and Karnataka, which eventually regulate the HM concentration and geo‐environmental processes in the region and affect the health risk to humans in one or the other way. The reference data generated from the present work are absolutely new and would be significant in the future for deriving sustainable development plans for the well‐being of human beings and precious natural resources.

Substituting partial chemical nitrogen fertilizers with organic fertilizers maintains grain yield and increases nitrogen use efficiency in maize

IntroductionLong-term application of excessive nitrogen (N) not only leads to low N use efficiency (NUE) but also exacerbates the risk of environmental pollution due to N losses. Substituting partial chemical N with organic fertilizer (SP) is an environmentally friendly and sustainable fertilization practice. However, the appropriate rate of SP in rainfed maize cropping systems in semi-arid regions of China is unknown.MethodsTherefore, we conducted a field experiment between 2021 and 2022 in a semi-arid region of Northern China to investigate the effects of SP on maize growth, carbon and N metabolism (C/NM), and NUE. The following treatments were used in the experiment: no N application (CK), 100% chemical N (SP0, 210 kg N ha–1), and SP substituting 15% (SP1), 30% (SP2), 45% (SP3), and 60% (SP4) of the chemical N. The relationship between these indicators and grain yield (GY) was explored using the Mantel test and structural equation modeling (SEM).Results and discussionThe results found that the SP1 and SP2 treatments improved the assimilates production capacity of the canopy by increasing the leaf area index, total chlorophyll content, and net photosynthetic rate, improving dry matter accumulation (DMA) by 6.2%–10.6%, compared to the SP0 treatment. SP1 and SP2 treatments increased total soluble sugars, starch, free amino acids, and soluble protein contents in ear leaves via increasing the enzymatic reactions related to C/NM in ear leaves during the reproductive growth stage compared with SP0 treatment. The highest plant nitrogen uptake (PNU) and nitrogen recovery efficiency were obtained under the SP2 treatment, and the GY and nitrogen agronomic efficiency were higher than the SP0 treatment by 9.2% and 27.8%. However, SP3 and SP4 treatments reduced DMA and GY by inhibiting C/NM in ear leaves compared to SP0 treatment. Mantel test and SEM results revealed that SP treatments indirectly increased GY and PNU by directly positively regulating C/NM in maize ear leaves. Therefore, in the semi-arid regions, substituting 30% of the chemical N with SP could be considered. This fertilizer regime may avoid GY reduction and improve NUE. This study provides new insights into sustainable cultivation pathways for maize in semi-arid regions.

Achieving ultrasensitive detection of glyphosate in fruits and vegetables using a triple-mode strategy based on carbon dots nanozymes derived from expired drugs

Rapid and sensitive detection of glyphosate (GLP) holds significant importance in the monitoring of environmental pollution and potential risks to human health. In this study, carbon dots nanozymes (CDszymes) with peroxidase-like activity were synthesized rapidly using a microwave-assisted method, employing expired drugs as raw materials. In the presence of H2O2, CDszymes catalyze the oxidation of TMB to generate blue oxTMB, which exhibits a photothermal effect under near-infrared light irradiation; an inner filter effect (IFE) may occur between oxTMB and CDszymes. By coupling the cascade catalysis of AChE and ChOx to generate H2O2, GLP effectively inhibits the activity of AChE, constructing a colorimetric/fluorescent/photothermal response platform for GLP. In colorimetry, the detection limit of GLP was 0.33 ng/mL. The detection limits of GLP by fluorescence method and photothermal method were 0.02 ng/mL and 0.41 ng/mL, respectively. The efficacy of this methodology has been successfully demonstrated in fruit and vegetable, it also provides a strategy for the high-value conversion of expired drugs.

Dense planting and nitrogen fertilizer management improve drip-irrigated spring maize yield and nitrogen use efficiency in Northeast China

Farmers in China often use nitrogen (N) fertilizers to ensure adequate crop growth. However, injudicious applications have increased the risk of environmental pollution, lower maize yields, and reduced profits for farmers. Appropriate N fertilizer management is crucial for improving yield and nitrogen use efficiency (NUE). This study conducted a three-year experiment involving nine N treatments (0, 45, 90, 135, 180, 225, 270, 315, and 360 kg ha-1) on a field under nitrogen fertilizer precision management (NFPM) in Northeast China. These results were compared with studies published within the past decade that analyzed yield and dry matter (DM) content under two management practices in Northeast China: conventional nitrogen fertilization management (CNFM) and water-saving fertilization management (WSFM). The findings reveal that maize yield increases with rising N application rates up to 270 kg ha-1, after which yield decreases. The kernel number (KN) and kernel weights (KW) of maize grown under NFPM were 13.7 and 14.7% higher than those grown under WSFM, respectively. Furthermore, they surpassed crops grown under CNFM by 38.4 and 21.2%, respectively. The maximum total yield of the NFPM treatment was 41.8 and 78.8% higher than WSFM and CNFM, respectively. Additionally, compared with CNFM and WSFM, NFPM significantly increased nitrogen use efficiency (NUE) across various N-level treatments. Optimizing nitrogen management could help farmers achieve higher yields and promote sustainable agricultural development.

Synthesis of rGO/CuBi2O4 nanocomposite as an effective photocatalyst in the reduction of nitroaromatic compounds to corresponding amines under visible light

AbstractBACKGROUNDChemical pollutants, such as nitroaromatic compounds, have been a significant challenge in recent decades of human societies as they contribute to environmental pollution and pose serious health risks due to their high toxicity. One promising and green method to address this issue is the photocatalytic reduction of nitroaromatic compounds to their corresponding amino aromatic compounds. In this study, an rGO/CuBi2O4 nanocomposite was synthesized using the hydrothermal method, involving the simultaneous reduction of graphene oxide and the coupling of CuBi2O4 nanoparticles in its layers. The resulting heterogeneous structure was characterized using various techniques including FTIR, Raman, XPS, XRD, FESEM, TEM, EDAX, UV–Vis DRS, BET, PL spectroscopy, and EIS. Subsequently, the photocatalytic efficiency of the nanocomposite in reducing nitroaromatic compounds to the corresponding aromatic amines under visible light was evaluated.RESULTSThe results indicated that graphene oxide was effectively reduced and coupled with CuBi2O4 nanoparticles in the reduced graphene oxide sheets. The rGO/CuBi2O4 heterogeneous nanocomposite successfully reduced nitroaromatic compounds to the corresponding aromatic amines under visible light. Hydrazine monohydrate was used to supply the necessary hydrogen for the reaction.CONCLUSIONThis study confirmed the high photocatalytic activity of the rGO/CuBi2O4 heterogeneous nanocomposite. Our nanocomposite was more effective than others, reported in similar studies, at reducing nitroaromatic compounds to the corresponding amino aromatic compounds. Additionally, it demonstrated high recycling and reuse properties, as there was no significant change in reaction conversion percentage and nanocomposite amount after 16 reuses. © 2024 Society of Chemical Industry (SCI).

RESEARCH ON COOKING OIL ABSORBENT PADS USING WATER HYACINTH MATERIALS

Cooking oil is an indispensable ingredient in everyday family cooking. The oil after use is often discharged directly into wastewater systems, leading to risks of environmental pollution, water pollution, clogging of drainage systems... In recent years, water hyacinth plants have been considered weeds, floating on rivers, canals, ponds and lakes, obstructing the circulation of boats and preventing water flow. Water hyacinth plants are often found in large rivers and almost no one cares about their uses, making them truly wasteful. Realizing the flexibility of water hyacinth when dried, it can be woven into pieces with good absorbent properties, our team has researched using water hyacinth as a material to absorb used cooking oil that is discarded into the environment. school. The research uses the main methods of experimental method and sample analysis method in its research. The result is that a product that absorbs discarded cooking oil scum is formed and is tested for cooking oil contaminated water with results consistent with QCVN 14:2008/BTNMT. The purpose of the research is to find effective products to absorb discarded cooking oil to save costs and contribute to environmental protection. The problem of using naturally available materials to create products that absorb cooking oil scum at the same time solves two current environmental problems. The research is a preliminary result, so there are still many shortcomings. We hope that in the future there will be further research to make the product more and more perfect

Daur Ulang Minyak Jelantah: Pengelolaan Limbah Domestik Rumah Tangga melalui Pembuatan Lilin Aromaterapi di Desa Sarirogo, Sidoarjo, Jawa Timur

The community service activity program that we carried out entitled MIGUNANI (Processing Used Cooking Oil Waste into Valuable Goods) involving the women of Sarirogo Village, Sidoarjo Regency, East Java was held on August 15, 2024. The purpose of this activity is to reduce the risk of environmental pollution due to used cooking oil waste by processing it into aromatherapy candles. Thus, used cooking oil waste, which can initially pollute the environment, can be turned into valuable goods and can become a business idea for additional income for mothers. The output targets produced are aromatherapy candles and devotion journals. In realizing the output targets, the methods used include socialization, training and direct practice to increase the creativity of participants. The hope of the activity program that we have carried out is that the participants will have knowledge and insight in processing used cooking oil waste into valuable goods and creative business ideas.

On-site monitoring and numerical simulation on groundwater flow and pollution plume evolution in a hexavalent-chromium contaminated site

Accurately ascertaining spatiotemporal distribution of pollution plume is critical for evaluating the effectiveness of remediation technologies and environmental risks associated with contaminated sites. This study concentrated on a typical Cr(VI) contaminated smelter being currently remediated using pump-and-treat (PAT) technology. Long-term on-site monitoring data revealed that two highly polluted regions with Cr(VI) concentrations of 162.9 mg/L and 234.5 mg/L existed within the contaminated site, corresponding to previous chromium slag yard and sewage treatment plant, respectively. The PAT technology showed significant removal performance in these highly polluted areas (>160 mg/L) after six months of pumping, ultimately achieving complete removal of the pollutants in these high-pollution areas. Numerical simulation results showed that although the current remediation scheme significantly reduced the Cr(VI) pollution degree, it did not effectively prevent the incursion of the pollution plume into the downstream residential area after 20 years. Additionally, an improved measure involving supplementary pumping wells was proposed, and its remediation effects were quantitatively evaluated. Results indicated that the environmental pollution risk of groundwater downstream could be effectively mitigated by adding pumping wells, resulting in a reduction of the pollution area by 20 % in the case of adding an internal well and 41 % with the addition of external wells after 20 years. The findings obtained in this study will provide an important reference and theoretical guidance for the reliability analysis and design improvement of the PAT remediation project.

High-output solid[sbnd]liquid triboelectric nanogenerator enhanced by the regulation of interfacial wettability

Triboelectric nanogenerators (TENGs), as a new strategy for harvesting energy from nature, have attracted widespread attention in the field of water droplet energy capture. As a friction layer material, the solidliquid electrification phenomenon of coatings has been studied. However, little attention is paid to the influence of the surface wettability of the coating itself on the electrical signal of the droplet generator. In this study, alkyl/phenyl pure silicone resin was utilized as a substitute for fluorine-containing polymer materials. This substitution not only mitigated the risk of environmental pollution from TENG friction materials but also resulted in varying wettability of the silicone resin coating through plasma and surface structure treatment. The droplet-based Double-electrode (D-TENG) and Single-electrode (S-TENG) coating-based triboelectric nanogenerators were fabricated. Through the integration of a high-speed camera and ammeter, the motion state of water droplets on surfaces with different wettability closely correlates with their charged behavior. This correlation is utilized to observe the motion state of water droplets on hydrophilic-hydrophobic surfaces in four stages: contact, spreading, contraction, and sliding. Under the double-electrode structure, as the water contact angle of the coating increased from 6.84° to 139.77°, the short-circuit current initially increased and then decreased, peaking at 466 µA when the contact angle was 98.48°, representing a 677-fold increase from the initial 0.689 µA. In the single electrode structure, the short-circuit current increased from 2.66 nA to 700 nA, indicating a 263-fold increase. Studying the varied wettability of the surface of silicone resin coating aids in comprehending the application of the coating material in solid-liquid friction electrification for energy collection. Furthermore, it offers insight into selecting appropriate coating materials for friction coatings in future applications.

A data-driven Ship Risk Profile model for Turkish Straits (TS-SRP) using Machine Learning

Marine accidents exhibit a higher frequency within ports, internal waters, and narrow waterways as compared to open seas, emphasizing the paramount concern of maritime authorities regarding the safe navigation of ships in congested waters. In response to this issue, coastal states, in addition to flag state and port state measures, institute preventive measures by conducting risk analyses in narrow waterways with geographical restrictions and high traffic density. To meet this need, this study aims to develop a Ship Risk Profile (SRP) model to monitor ships by evaluating the potential risks of the ships passing through narrow waterways and taking the necessary precautions proactively by Vessel Traffic Service (VTS) for mitigating the potential accident and environmental pollution risk. The Turkish Straits is determined as the application area for this paper. The proposed model employs Machine Learning (ML) methods and analyzes targeting factors from Port State Control (PSC), ship particulars obtained from Sailing Plan (SP)-1 reports specific to the Turkish Straits, as well as relevant environmental factors. The results demonstrate that the developed model holds promise for improving safety in Turkish Straits and can be adapted by VTSs in other sea regions by customizing it to suit their specific characteristics and conditions.

Pemanfaatan Limbah Ikan Menjadi Pakan Bernutrisi Tinggi Solusi Inovatif Dalam Sektor Perikanan Di Kabupaten Kepulauan Selayar

Fishery waste consists of liquid and solid waste, accounting for 30-40% of the total weight of fish, mollusks, and crustaceans. Unfortunately, fish waste has not been well-managed due to its low economic value. However, with the advancement of technology, the opportunity to process fish waste into high-value products is increasingly open. Modern technology enables fish waste to be converted into high-quality fish feed, reducing the cost of commercial feed. The utilization of fish waste not only generates positive economic impacts but also significant environmental benefits. Processing fish waste into feed can reduce the risk of environmental pollution, decrease greenhouse gas emissions, and reduce pressure on wild fish resources. The use of feed from fish waste helps to promote more sustainable and environmentally friendly aquaculture practices. Research results show that using fish waste as an alternative feed in shrimp farming provides dual benefits for the environment and economy. Therefore, standard quality regulations are needed to ensure effective and safe management of fish waste for the environment and human health.

Resilience quantification and recovery strategy simulation for urban underground logistics systems under node and link attacks: A case study of Nanjing city

Urban Underground Logistics Systems (UULS) have become an emerging solution to mitigate urban surface traffic congestion, environmental pollution, and surface transport safety risks. However, during the operation of UULS, the use of advanced technologies such as the Internet of Things (IoT) introduces cybersecurity risks to the system. Moreover, severe natural disasters can also cause damage to underground transportation network links. Existing research and planning primarily concentrate on the system design and benefits of UULS, neglecting the system's service level under attack scenarios. This study outlines three representative UULS network prototypes and proposes a resilience quantification method centered on logistics efficiency. It also focuses on comparing the effectiveness of three recovery strategies. These strategies give priority to maximum flow, betweenness centrality, and regional importance, as well as the priority of node and link repairs. The resilience quantification method and recovery strategies are applied in a case study set in Nanjing City. The case study results reveal that the Two-echelon network shows exceptional resilience. Regarding the effectiveness of recovery strategies, the strategy based on maximum flow proves to be the most effective, and focusing on node repair can lead to higher system resilience. Based on these findings, this study offers recommendations to transportation and logistics management decision-makers, focusing on UULS resilience and recovery strategy selection. These recommendations are intended to provide valuable guidance for the planning and design of future UULS, ensuring their resilience and reliability.

Study of nitrogen and phosphorus nutrient dynamics in concentrated marine fish farming water environment in Long Son - Vung Tau

The nutritional content of N and P in concentrated marine fish farming water in the Cha Va - Long Son - Vung Tau estuary area increased sharply during 2013–2016; notably, the N-NH4+ content increased in 2017–2019. The N-NO2- and N-NO3- content in the dry season (0.051 mg/L and 0.190 mg/L) was higher than in the rainy season (0.044 mg/L and 0.133 mg/L). In contrast, the N-NH4+ and P-PO43- contents in the rainy season (0.321 mg/L and 0.1 mg/L) are higher than in the dry season (0.154 mg/L and 0.093 mg/L). The N and P nutrient dynamics in water fluctuate according to the semi-diurnal tide regime; the nutrient content decreases during high water - daytime, increases during low water in the evening, and is high during high water at night and in the morning, early the next day. In dry and rainy seasons, the N-NH4+ content is always the highest (0.024–0.761 mg/L) among the nitrogen-based nutritional parameters. N and P nutrients in water are correlated: N-NH4+ parameter pairs with Total P, N-NO2- with Total P, Total N with Total P, N-NO2- and N-NO3-, P-PO43- with Total P, and the parameter pair N-NO2- with P-PO43- have low positive correlation coefficients (r), from 0.1–0.21. Conversely, the parameter pairs N-NO3- and Total N, N-NO3- and N-NH4+, and N-NO2- and N-NH4+ have low negative correlation coefficients (r), from -0.12 to -0.26. From 2010–2021, the number of cages increased beyond planning, causing environmental pollution in the water in the farming area. The nutritional RQ value of the water is high at level 4 every year (very high risk of environmental pollution).

Analysis of Solid Waste Treatment and Management in Typical Chinese Industrial Parks with the Goal of Sustainable Development and Future Suggestions

Solid waste disposal and management have become a global problem, which is particularly tricky in China with its large population and rapid urbanization. This study focused on the disposal status of multi-source solid waste as well as the park management of some typical cities of China. Firstly, the main technical methods for solid waste disposal were summarized as follows: landfill, incineration, anaerobic digestion and aerobic compost. Secondly, the network analysis method was applied to seek an optimized method for solid waste disposal and management. Thirdly, typical demonstration parks for solid waste disposal and management were analyzed to study their respective operating modes and strategies for synergistic development in terms of resources, environment and economy and to explore the sustainable development potential of the Guangdong–Hong Kong–Macao operating mode. The results showed that the collaborative disposal and recycling of solid waste are important for cities (especially megacities) to achieve resource conservation and environmental protection. The NIMBY effect and environmental pollution risks caused by decentralized construction could be reduced through the construction of circular industrial parks. Advanced technologies and the national policy for solid waste disposal and recycling in industrial parks of small–medium cities, large–medium cities and megacities were systematically analyzed so as to explore a self-operating management mode of industrial parks. Finally, reasonable suggestions, such as sharing, saving and cycling and propaganda education, as well as green and low-carbon solutions were put forward for solid waste disposal and management in typical industrial parks, effectively resolving the contradiction between economic development and environmental protection so as to help urban sustainable development.

Supercritical CO2 Fluid Extraction and Microencapsulation of Oil from Anchovy (Engraulis mordax) By-Products

Research background. Fish by-products are discarded as waste, which has a significant impact on the environment. They have no economic value, but there are many opportunities to turn them into high value products. Due to significant quantities generated internationally and the continuous expansion of the market for ω-3 and ω-6 fatty acids as nutraceuticals, innovative technological approaches are needed to transform this waste into marketable products with added value, while limiting the risk of environmental pollution. Experimental approach. In this study, two temperatures (40 and 60 °C) at a constant pressure during the extraction of anchovy by-products with supercritical CO2 fluid were used to determine extraction yield, fatty acid, tocopherol and phytosterol composition, followed by microencapsulation with two matrices based on the transglutaminase-mediated crosslinking reaction between whey protein isolates and casein. Before microencapsulation, the binding parameters were estimated using quenching studies. Results and conclusions. The results showed a higher content of total fatty acids when extracted at 40 °C, resulting in two fractions on a dry mass basis of (712±12) mg/g in the fraction obtained in the separator with code S40 and (732±10) mg/g in the fraction obtained in the separator with code S45, respectively. The monounsaturated (MUFAs) and polyunsaturated fatty acids (PUFAs) accounted for 40–44 %. The extracts showed a higher mass fraction of eicosapentaenoic acid ((28.7±1.0) mg/g) in fraction S45 when extracted at 60 °C. A minimum inhibitory and bactericidal concentration of 0.66 μg/mL against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 was found for all fractions. Higher binding constants were found for palmitoleic and oleic acids than for palmitic acid. The control variant, without crosslinking, enabled the microencapsulation of a higher amount of fatty acids, while in both powders the sum of MUFAs and PUFAs was 40 %. Novelty and scientific contribution. The approaches used in our study open up new opportunities for adding value to the fish by-products through extraction and microencapsulation, extending their potential use to food, cosmetics and nutraceuticals.