Water Concentration Research Articles

Allelopathic activity of coffee extracts: implications for germination and initial growth in select weeds and polyploidy in Lactuca sativa L

ABSTRACT Coffee beans contain compounds with allelopathic activity, such that some beans that do not meet quality standards might rather be used to obtain a natural herbicide which consequently might be employed to control undesired plants and avoid economic losses. Thus, the objectives of this study were: (1) to investigate the allelopathic effect of different concentrations of green (GC) and roasted (RC) coffee extracts on the inhibition of germination and initial growth of Lactuca sativa L. Bidens pilosa L. and Cyperus rotundus L. and (2) determine the induction of changes in the cell cycle of L. sativa L. and (3) quantify some compounds in the GC and RC extracts with possible allelopathic effects. Seeds and tubers were sown on germination paper, moistened with water or different concentrations of extracts, stored in transparent plastic boxes, and maintained in a germination chamber. Caffeine was found at higher concentrations of 79.768 and 15.532 g/L in GC and RC extracts, respectively. In general, RC extract for L. sativa L. and GC for B. pilosa L. diminished germination parameters. For C. rotundus L. GC extract decreased growth regardless of the concentration. An increased frequency of cell cycle alterations was observed in the root cells of L. sativa L. This study is the first to report that the studied extracts possess allelopathic potential, as they are effective in reducing germination and/or initial growth of weed species and L. sativa L. as well as inducing alterations in the cell cycle of L. sativa L.

Invisible Peril: Assessing microplastic pollution in Ghanaian mangroves

Mangroves are key providers of crucial ecological services. This study's aim is to investigate the levels of microplastic (MP) contamination in mangroves from Ghana's Western and Central regions. A total of 1303 particles were analysed from sediment and water samples, 65 % comprising MPs. West and Central regions had notable differences in MPs abundance. Sediment had the highest number of MPs (703 MPs), with concentrations ranging from 0.01 to 2.23 MPs/g·dw, whilst concentrations in water ranged from 0.2 to 3.75 MPs/l. Fibre shapes were the most abundant MP (67 %) followed by fragments. Ten different groups of polymers were found, with polyester, polyethylene and polypropylene being the most abundant. Synthetic hair, textile and water sachets/small plastic bags were expected to be the source of most MPs collected. High population abundance was shown to be related to high levels of MPs. Our findings suggest reducing single-use plastics, waste management/treatment, and clean drinking water, could reduce the impact of MPs in Ghana.

Experimental Study on the Alternate Oil Displacement Mechanism of CO2 and Modified Water in Low-Permeability Oil Layers

Alternating carbon dioxide and water flooding can not only seal greenhouse gases, but also combine the advantages of water flooding and carbon dioxide flooding, and can well control mobility and stabilize the displacement front, thereby greatly improving the macro-replacing efficiency. In order to further improve the development effect of water–carbon dioxide alternating flooding, this paper, based on sufficient collection of the literature, research, and analysis, pre-uses modified water instead of water, and deeply explores and studies the impact of modified water–carbon dioxide alternating flooding on the improvement of development effect and the mechanism of enhancing oil recovery in low-permeability reservoirs. The main work completed is as follows: (1) A comparative experiment of multiple groups of sand-filled tubes with different displacement media, modified water concentrations, and injection plug sizes was conducted under the conditions of simulating reservoir formation temperature of 70 °C and formation pressure of 18 MPa, and the optimal scheme and injection parameters of alternating modified water and carbon dioxide flooding were rationally selected. The results show that the alternating flooding of modified water and carbon dioxide in low-permeability reservoirs can significantly improve the development effect. The optimal injection parameters are a formulation concentration of 0.3% and an injection method of alternating a 0.1 PV slug injection of carbon dioxide and modified water. (2) Using Berea cores instead of sand-fill tubes, a comparative experiment of alternating oil displacement using carbon dioxide and modified water was carried out under the same experimental conditions. Nuclear magnetic resonance measurements were performed on five of the cores to analyze the microscopic oil displacement mechanisms of different displacement media. The results show the following: nuclear magnetic resonance testing shows that carbon dioxide displacement can greatly improve the oil recovery efficiency in tiny pores (about 47.43%); alternating injection can further improve the oil recovery efficiency in tiny pores (about 70.6%); and modified water can improve the oil recovery efficiency in larger pores (about 56.47%).

Effects of Salinity of Magnetized Water on Water–Salt Transport and Infiltration Characteristics of Soil Under Drip Irrigation

The shortage of fresh water resources and soil salinization restrict the sustainable development of oasis agriculture in Xinjiang, China. Magnetically treated brackish water can physically improve the quality of water used for irrigation, and this technology is being gradually applied in agricultural production. However, the infiltration characteristics of magnetized brackish water and its response to the distribution of soil water and salt are still unknown. We conducted infiltration tests using a one-dimensional soil column system, employing magnetized water at concentrations of 0.2, 1, 3, and 5 g·L⁻1, with a magnetization strength of 3000 gauss (GS), and explored the effects of salinity of magnetized water on water–salt transport and infiltration characteristics of soil under drip irrigation. The migration rate of the wetting front of magnetized water infiltration slowed, and the cumulative infiltration content increased. Specifically, compared to the unmagnetized control, the infiltration time at a depth of 40 cm for magnetized water concentrations of 0.2, 1, 3, and 5 g·L−1 increased by 17.42%, 42.16%, 47.02%, and 39.19%, respectively. Correspondingly, the cumulative infiltration volume increased by 7.88%, 8.09%, 10.60%, and 5.38%. Further, the infiltration of magnetized brackish water increased the water retention capacity of soil, effectively reduced the salt content of soil layers, and had a remarkable desalting effect. Salinity of the soil profile showed an L-shaped trend of salt accumulation in the lower layer and desalting in the upper layer. For water salinity of 3 g·L−1, soil desalting intensity was greatest. In addition, KShf, suction rate, empirical coefficient a, initial infiltration rate, and stable infiltration rate all decreased under magnetization treatment with the same salinity. Thus, this study provides a new way to alleviate the shortage of fresh water resources in arid areas, a guideline for safely using brackish water and also increasing productivity of saline–alkali land.

Factors influencing the dissolution rate of radon gas in water

Measurements of radon (222Rn) in water are widely utilized across various disciplines, including technology, medicine, exploration, and ecological preservation. For accurate radon measurements in water, the availability of a standardized radon solution is essential. Researchers have predominantly concentrated on the radon concentration in water (RCW) once radon distribution equilibrium is achieved, rather than the rate of radon dissolution prior to equilibrium, in the development of standard radon solutions. This makes the preparation speed of the calibration standards radon solution slow, which seriously restricts the research and development of the standard device. The purpose of this paper is to investigate the correlation between the rate of radon dissolution and both the concentration of gaseous radon and the stirring speed. Four conclusions have been derived through univariate analysis. ➀ The radon concentration in water (RCW) increases with the duration of radon dissolution, eventually reaching a state of equilibrium. ➁ The increase in gas radon concentration correlates with a simultaneous rise in the rate of radon dissolution, while the time required for radon distribution equilibrium remains constant. ➂ The augmentation of the stirring speed enhances the rate of radon dissolution, Concurrently reducing the time needed for RCW to reach equilibrium.➃ When the stirring speed is excessively high, it results in substantial fluctuations in both RCW and the rate of radon dissolution. Consequently, when employing this method for the preparation of radon solutions, it is advisable to regulate the duration of radon dissolution to 30 min at a rate of 380 rad/min and 10 min at a rate of 480 rad/min. This regulation ensures the attainment of precise concentrations. Under conditions of environmental stability, manipulation of gas radon concentration alone proves sufficient for adjusting RCW . These empirical findings furnish a robust foundation for the efficient preparation of standardized radon solutions and the requisite apparatus, essential for the calibration and accuracy of radon measurement instruments.

Occurrence and characteristics of microplastics across the watershed of the world’s third-largest river

While rivers as primary conduits for land-based plastic particles transferring to their "ultimate" destination, the ocean, have garnered increasing attention, research on microplastic pollution at the scale of whole large river basins remains limited. Here we conducted a large-scale investigation of microplastic contamination in water and sediment of the world’s third-largest river, the Yangtze River. We found concentrations of microplastics in water and sediment to be 5.13 items/L and 113.9 items/kg (dry weight), respectively. Moreover, microplastic pollution levels exhibited a clear decreasing trend from upstream to downstream. The detected microplastics were predominantly transparent in color, with fibrous shapes predominating, sizes mainly concentrated below 1mm and composed primarily of PP and PE polymers. Our analysis results indicated that compared to geographical and water quality parameters, anthropogenic factors primarily determined the spatial distribution pattern of microplastics. Moreover, the microplastic abundance in sediment upstream of the dam was significantly higher than that in the downstream sediment, while the trend of microplastic concentrations in water was opposite. Therefore, more effort is needed to monitor microplastic contamination and their ecological environmental effects of sediment before dams in future research.

A novel hybrid deep learning model for real-time monitoring of water pollution using sensor data

This study developed a hybrid model for predicting dissolved oxygen (DO) using real-time sensor data for thirteen parameters. This novel hybrid model integrated one-dimensional convolutional neural networks (CNN) and long short-term memory (LSTM) to improve the accuracy of prediction for DO in water. The hybrid CNN-LSTM model predicted DO concentration in water using soft sensor data. The primary input parameters to the model were temperature, pH, specific conductivity, salinity, density, chlorophyll, and blue-green algae. The model used 38,681 water quality data for training and testing the hybrid deep learning network. The training procedure for the model was successful. The training and test losses were both nearly zero and within a similar range. With a coefficient of determination (R2) of 0.94 and a mean squared error (MSE) of 0.12, the hybrid model indicated higher performance compared to the classical models. The normal distribution of residual errors confirmed the reliability of the DO predictions by the hybrid CNN-LSTM model. Feature importance analysis indicated pH as the most significant predictor and temperature as the second important predictor. The feature importance scores based on extreme gradient boosting (XGBoost) for the pH and temperature were 0.76 and 0.12, respectively. This study indicated that the hybrid model can outperform the classical machine learning models in the real-time prediction of DO concentration.

The influence of water conservancy project on microplastics distribution in river ecosystem: A case study of Lhasa River Basin in Qinghai-Tibet Plateau

Water conservancy projects affect the migration, suspension, and deposition of microplastic (MP). However, its impact on MP pollution of river ecosystem remains elusive. Herein, we investigated the MP characteristics and the influence of water conservancy projects on MPs in the Lhasa River Basin of the Qinghai-Tibet Plateau, China. The results demonstrated that the MPs concentration in surface water decreased from upstream to downstream, as more MPs in surface water were settling down and stored in reservoir sediments in the midstream. It is postulated that reservoir sedimentation of MPs occurs at a greater rate due to the barrier effect of reservoirs, steady hydrodynamics, and weak salinity-induced buoyancy. To evaluate the ecological risk of the Lhasa River Basin, the pollution load index, the polymer hazard index, and the potential ecological risk index were analyzed. The upstream exhibits elevated polymer hazard index values (>100), and the potential ecological risk index values in the Lhasa River Basin showed ecological risk similar to those of pollution load index values. This research represents the initial exploration of MP distribution within the entire Lhasa River basin, providing a foundational framework for investigating the impact of water conservancy projects on MP migration.

Using δ65Cu and δ34S to determine the fate of copper in stream waters draining porphyry mineralization: Implications for exploration targeting

The fate of metals, such as Cu, in stream waters draining porphyry mineralization is commonly controlled by several natural processes such as sorption, microbial processes, and ligand availability. Isotopes of Cu offer a novel approach to understanding these processes and determining metal sources within complicated mineralogical systems. Drainages at the Casino Cu-Au-Mo porphyry deposit, Yukon, Canada exhibit circumneutral (pH > 5) in Casino Creek and natural acid rock drainage (pH < 3.5) in Proctor Gulch with the precipitation of schwertmannite (Fe3+). Isotopic systems δ65Cu and δ34Ssulfate indicate different metal sources, with signatures of both hypogene and supergene mineralization. Waters from Proctor Gulch contain δ65Cu values (< −0.5 ‰) consistent with supergene Cu sources from the leached or oxide portion of the mineralization. Comparatively, drainage in the upper part of Casino Creek contains a δ65Cu composition (> 0.5 ‰) characteristic of Cu sourced from hypogene sulfide mineral oxidation. Variation in metal sources is similarly supported by aqueous δ34Ssulfate values in the stream waters, which suggest mixing of S derived from a sulfide mineral phase and a much heavier sulfate mineral (e.g., gypsum or anhydrite). Isotopic fractionation of Cu in the dissolved (<0.45 μm) phase presents two predominant controls on Cu dispersion. The natural acid conditions in Proctor Gulch favor the preferential co-precipitation of 63Cu with schwertmannite but could be influenced by intracellular assimilation or adsorption by microbes, which also has been shown to preferentially favor 63Cu. Copper isotopic fractionation results in a gradient of increasing δ65Cu values in waters downstream. In Casino Creek, higher pH conditions favor the precipitation of Fe(OH)3 and the preferential adsorption of 65Cu, resulting in decreasing δ65Cu values downstream. Copper concentrations in stream waters remain elevated (up to 4.1 μg/L) above ambient background (1.9 μg/L) levels up to 11 km downstream of the deposit. Given the abundance of surface water in many parts of northern Canada, hydrogeochemical prospecting using broad scale stream water catchment analysis is clearly a viable greenfield exploration methodology.

BioRT-HBV 1.0: A Biogeochemical Reactive Transport Model at the Watershed Scale.

Reactive Transport Models (RTMs) are essential tools for understanding and predicting intertwined ecohydrological and biogeochemical processes on land and in rivers. While traditional RTMs have focused primarily on subsurface processes, recent watershed-scale RTMs have integrated ecohydrological and biogeochemical interactions between surface and subsurface. These emergent, watershed-scale RTMs are often spatially explicit and require extensive data, computational power, and computational expertise. There is however a pressing need to create parsimonious models that require minimal data and are accessible to scientists with limited computational background. To that end, we have developed BioRT-HBV 1.0, a watershed-scale, hydro-biogeochemical RTM that builds upon the widely used, bucket-type HBV model known for its simplicity and minimal data requirements. BioRT-HBV uses the conceptual structure and hydrology output of HBV to simulate processes including advective solute transport and biogeochemical reactions that depend on reaction thermodynamics and kinetics. These reactions include, for example, chemical weathering, soil respiration, and nutrient transformation. The model uses time series of weather (air temperature, precipitation, and potential evapotranspiration) and initial biogeochemical conditions of subsurface water, soils, and rocks as input, and output times series of reaction rates and solute concentrations in subsurface waters and rivers. This paper presents the model structure and governing equations and demonstrates its utility with examples simulating carbon and nitrogen processes in a headwater catchment. As shown in the examples, BioRT-HBV can be used to illuminate the dynamics of biogeochemical reactions in the invisible, arduous-to-measure subsurface, and their influence on the observed stream or river chemistry and solute export. With its parsimonious structure and easy-to-use graphical user interface, BioRT-HBV can be a useful research tool for users without in-depth computational training. It can additionally serve as an educational tool that promotes pollination of ideas across disciplines and foster a diverse, equal, and inclusive user community.

Effects of the insecticide chlorpyrifos on Amazonian freshwater invertebrates: A mesocosm experiment

Chlorpyrifos is one of the most widely used insecticides globally, yet its toxicity for tropical aquatic ecosystems in Latin America has not been thoroughly evaluated. In this study, we conducted a 70-day mesocosm experiment to assess the effects of chlorpyrifos on zooplankton and macroinvertebrate communities representative of the Ecuadorian Amazon. Mesocosms were exposed to a single application of chlorpyrifos at four nominal concentrations (0.01, 0.1, 1, and 10 μg/L). Results showed rapid chlorpyrifos dissipation, with a half-life of 1.2 days. For some Rotifera species, including Polyarthra luminosa and Anuraeopsis sp., a consistent No Observable Effect Concentration (NOEC) of 0.01 μg/L was identified. Cyclopoida (e.g., Macrocyclops sp.) also displayed treatment-related declines, with a NOEC of 0.1 μg/L. Among macroinvertebrates, the most sensitive taxon was the Ephemeropteran Caenis sp. (NOEC: 0.1 μg/L), while other insect taxa (Odonata, Diptera) also showed significant treatment-related declines. Based on the response of some Rotifera species and the zooplankton community, we determined a mesocosm NOEC of 0.01 μg/L. The response of Rotifera taxa was explained by indirect effects resulting from a decline in copepod populations within the experimental systems, which led to an increase in Cladocera (e.g., Moina sp.), effective grazers on small rotifers. Our findings suggest a mesocosm NOEC slightly lower than those reported in other tropical and temperate studies (0.1 μg/L), potentially due to differences in species composition and interactions. Finally, our study highlights that measured chlorpyrifos concentrations in Latin American surface waters exceed levels at which both direct and indirect effects have been observed. Additional monitoring and regulatory measures are needed to control chlorpyrifos use and environmental release in tropical regions with intensive agriculture and high rainfall.

Preventive potential of arginine incorporated in fancy waters for erosive tooth wear

Objective(s): The aim of the study was to examine the potential of arginine (Arg)-enriched fancy waters in preventing erosive tooth wear. MethodsL-arginine (2% w/v.) was added to five commercial fancy waters: Oasis-Lemon, Oasis-Lemon Mint, Perrier-Lemon, Perrier-Grapefruit, Pellegrino-Lemon; and deionized water served as a negative control. The pH, buffer capacity of added Arg, and F− concentrations were measured. Tooth specimens were prepared and baseline volumetric assessment (T0) was conducted using micro-CT. Subsequently, the specimens were immersed in fancy waters for 72 h, kept in an incubator (37 ℃) and solutions were changed every 24 h. After the experimental cycle (T1), 3D volumetric analysis was performed, and 3D structural images were reconstructed for qualitative assessment. Results: The pH and F− concentrations of fancy waters with Arg were significantly higher than the control (p<0.001). The buffer capacity of added Arg with Perrier-Grapefruit was significantly higher than Oasis-Lemon, Oasis-Lemon Mint & Pellegrino-Lemon (p<0.05), except for Perrier-Lemon (p>0.05). At T1, the specimen volume in Oasis-Lemon Mint (+/- Arg) and Pellegrino-Lemon (control) was significantly lower than T0 (p<0.05). At T1, the specimen volume of Oasis-Lemon Mint and Pellegrino-Lemon (control) was significantly lower than Arg-containing fancy waters (p<0.05). Surface contrast indicating wear was evident from T0 to T1 in specimens from the Oasis-Lemon Mint (+/- Arg) and Pellegrino-Lemon (- Arg). Conclusion: Incorporating Arg in fancy waters reduces the potential of erosive tooth wear associated with these beverages. Clinical significance(44 words): Consuming fancy water beverages (flavoured sparkling/carbonated) can lead to erosive tooth wear in young people. Incorporating Arg in fancy water beverages can prevent the erosive wear potential of these beverages while alleviating the burden of oral care on individuals at risk to erosive wear.

Effective pervaporation dehydration of acrylic acid using alginate/BaTiO3 and alginate/TiO2 mixed matrix membranes

To develop an efficient pervaporation technique for acrylic acid dehydration, four types of BaTiO3 and TiO2 particles with various shapes and structures (commercial solid TiO2-S, synthesized sea urchin-like TiO2-U, commercial solid BaTiO3-S, and synthesized porous BaTiO3-P) were incorporated into sodium alginate (NaAlg) to fabricate mixed matrix membranes (MMMs) for comparison. 18 h crosslinking with CaCl2 was conducted to improve the acid-resistant property of Alg-based membrane. The filler particles and MMMs were systematically characterized via SEM, FTIR, BET, XRD, AFM, EDX, and TGA. The hydrophilicities of MMMs were enhanced with increasing filler contents, evidenced by the decreased water contact angles and raised water swelling degrees. When applied to pervaporate 5 wt% water/acrylic acid solution at 25 ℃, the MMMs significantly improved total permeation fluxes and separation factors compared to the pristine Alg membrane. When TiO2 particles were incorporated, the Alg/TiO2-U MMMs obtained lower separation factors than the Alg/TiO2-S MMMs due to the increased acrylic acid transport through big nanorod gaps and interfacial voids formed by the sea urchin-like TiO2-U shapes. On the other hand, the Alg/BaTiO3-P MMMs were superior to the Alg/BaTiO3-S MMMs in the dehydration performance, which was attributed to their porous structures. The optimal separation efficiency occurred at Alg/2 % BaTiO3-P MMM (water purity of 99.8 wt% and separation factor of 8700) with a stable performance over 168 h. When the optimal filler content was exceeded, the separation factor would decrease owing to the extra voids resulted from particle agglomeration. Moreover, the pervaporation performance could be enhanced with increasing feed temperature. In contrast, the separation selectivity was reduced, but the total permeation flux was improved, with increasing feed water concentration. It was further confirmed that the Alg/2 % BaTiO3-P MMM could successfully pervaporate a three-component mixture (10.3 wt% water/acetic acid/acrylic acid) at 65 ℃ to produce high-purity water (98.3 wt%). In conclusion, the design of Alg/BaTiO3 and Alg/TiO2 MMMs provides a potential approach for effective acrylic acid dehydration.

Optimization and greenness assessments of the supramolecular solvent-assisted cloud point extraction method for copper spectrophotometric determination in water and food samples

For the first time, the green supramolecular solvents (SUPRASs)-based cloud point extraction (CPE) approach was created for copper spectrophotometric determination in food and water samples. SUPRASs were synthesized in six different forms and used as synergistic reagents. SUPRAS (water, salicylic acid, and THF) mixed with TritonX-114 (TX-114) to be the most efficient extraction solvent. The validation investigation found that the linearity range, limit of detection (LOD), limit of quantification (LOQ), enhancement factor (EF), and preconcentration factor (PF) are 0.2-700.0 μg L-1, 0.1 μg L-1, 0.33 μg L-1, 85.0, and 50.0, respectively. The technique's accuracy was calculated using standard reference materials (SRMs) (GBW07605 Tea Leaves and GBW10019 Apple) and ranged between 96.0 and 98.9%. Lastly, a novel SUPRAS-CPE approach was utilized to determine copper concentrations in real water, food tests, and SRMs. Furthermore, the SUPRAS-CPE conforms to green chemistry principles by using less both time and energy than previous studies. Also, the greenness values were determined by three recent tools. The Analytical Greenness Metric for Sample Preparation (AGREEprep), Complex Modified GAPI (ComplexMoGAPI), and Sample Preparation Metric of Sustainability (SPMS) programs produced results of 0.79, 86.0, and 8.42, respectively. These results are strongly aligned with both green ideals and environmentally friendly practices. The finding increases the possibilities for using SUPRAS-CPE to extract additional mineral ions.

Heavy metal concentration in marine water: An assessment of ONGC’s blocks in Mumbai High Region, Arabian Sea

Heavy metal pollution, in the aquatic ecosystem, has become an area of concern garnering increasing attention since the past few decades. Some metals like manganese (Mn), copper (Cu), iron (Fe) and zinc (Zn) are biologically important for marine life. Other non-essential metals like lead (Pb), cadmium (Cd), and Arsenic (As) become toxic at higher concentrations. These metals are introduced into the marine ecosystem mainly due to anthropogenic activities. Hence, monitoring the heavy metal concentrations in these marine water over a period of time is of great help in checking the pollution level and identifying the trend, which in turn will be instrumental in formulating sustainable practices. The paper mainly focuses on the study of the concentration of lead (Pb), cadmium (Cd), and Arsenic (As) in sea water around the operational areas of ONGC in Waestern offshore. The distribution of heavy metals in the seawater of ONGC’s exploratory blocks in Mumbai High Region, Arabian Sea was studied. Fifty four sea water samples were collected as per OSPAR Commission guidelines from each blocks (Block A, Block B, Block C, Block D and Block E) of Mumbai High Region, Arabian Sea and processed samples were analyzed by ICP-MS for Pb, As, and Cd. Comparison of average results in studied 5 blocks with various seawater quality guidelines is discussed to assess the present level of contamination. The study reveals that seawater in study area is not contaminated with respect to perceived heavy metals. Generated data will assist in future for proactive measures to minimize the impact of anthropogenic sources.

The Growth of Oyster Mushroom on Ramie Chip Waste-Derived Media was Accelerated by Rice-washed Water

Rice-washed water is wastewater resulted from the rice cleaning process that is rich in nutrients. The use of ramie chip waste can be considered a potential substrate due to its lignocellulosic nature, similar to other wastes studied. This study aimed to examine the effect of rice-washed water on the mycelium and pinhead growth of white oyster mushrooms grown in the ramie chip waste as the growing medium. The experiment was conducted for three months using a completely randomized design with four rice-washed water treatments and six replications. The rice-washed water concentration treatments were 0% (K0), 25% (K1), 50% (K2), and 100% (K3), which were added to the ramie chip waste as the growing medium for white oyster mushroom. The time of mycelium propagation velocity, the time the first pinhead appearance, the number of mushroom bodies, and the largest cap diameter were observed. The results showed that ramie chip waste-derived media was suitable to cultivate white oyster mushrooms. Adding 100% rice-washed water to the media significantly affected the speed of mycelium propagation (16.51 days) compared to control (30 days) and the appearance of the first pinhead (31.5 days) compared to control (38.5 days) as well as the number of fruiting bodies of mushroom (8.8) compared to control (6.2). However, the rice-washed water application did not significantly affect the diameter of the largest mushroom cap.

Greenhouse gas concentrations in tropical wetlands of the Cross River estuary, Nigeria

The Cross River estuary is a coastal wetland in the south-eastern part of the Niger Delta region of Nigeria with its hydrological cycle largely dependent on precipitation. The purpose of this study was to determine the greenhouse gas (GHG) concentrations in water from selected wetlands in the Cross River estuary. Water samples were collected from the Ikang, Anantigha and Adiabo wetlands and the major GHGs were analysed using a gas chromatography coupled to a mass spectrometer. The mean concentration levels of carbon dioxide (CO2), nitrous oxide (N2O) and sulphur oxide (SO2) were measured in the water samples for both seasons. There was a significant difference in concentrations of all the greenhouse gases in the water samples for both seasons. The exceptions were: SO2 in Adiabo, CO2 in Anantigha and N2O in Ikang, which showed insignificant differences for both seasons. The water CO2 concentrations from the Adiabo wetland recorded the largest contribution of greenhouse gas levels, ranging between 6.88 ± 2.22 ppm and 11.02 ± 2.52 ppm. These levels were in the range of those reported in the Congo basin. The variation in concentrations could be due to location, hydrological characteristics, nutrient load injection or the nitrification and denitrification processes of wetlands.

Optimizing multi-surface modelling of available cadmium as measured in soil pore water and salt extracts of soils amended with compost and lime: The role of organic matter and reactive metal

The effectiveness of strategies to reduce cadmium (Cd) availability for crop uptake can be assessed using various measures of Cd availability, such as Cd concentration in pore water and Cd extracted with salt solutions. This study evaluated the performance of multi-surface modelling (MSM) to predict dissolved Cd in two Irish tillage soils treated with lime, zinc (Zn) and spent mushroom compost (SMC). Predictions were assessed against Cd measured in three solution media, i.e., 1 mM Ca(NO3)2 and 0.1 M CaCl2 extractions, as well as in soil pore water. Results indicate that reactive soil organic matter (SOM) may be underestimated using a single 0.1 M NaOH extraction in the investigated soils, leading to substantial overestimation of dissolved Cd by MSM, particularly at higher pH. Repeating the 0.1 M NaOH extraction three times substantially improved model predictions. Additionally, using reactive Cd determined by isotopic dilution instead of 0.43 M HNO3 improved model predictions for one of the soils that was rich in manganese (Mn) oxides, revealing a possible role of Mn oxides in determining the reactive Cd fraction. After optimizing reactive SOM and reactive Cd, residuals between predicted and measured Cd showed an increasing trend along with increasing solution pH and decreasing dissolved Cd. This is likely related to Cd binding to high affinity sites due to uncertainties in the binding parameters for these sites and/or to slow desorption kinetics for Cd bound to these sites. Despite significant variations in solution properties, including higher dissolved Ca and reactive dissolved organic matter (DOM), 1 mM Ca(NO3)2 extracts exhibited similar extractable Cd levels, model performance, and Cd speciation compared to soil pore water especially at higher pH. Thus, 1 mM Ca(NO3)2 can be a reliable proxy for soil pore water in assessing Cd availability for crop uptake in soils with circumneutral to alkaline pH.

Synergy effect of Ag nanoparticles and deep eutectic solvents in the CO2 capture process: A computational approach

The worsening of global warming has caused several problems for the planet, especially due to the high CO2 emissions in the atmosphere. Then, it is necessary to find new ways or improve the ways already used to capture the CO2 gas. This work reported through Molecular Dynamics (MD) simulations, the use of silver nanoparticles (AgNP) to improve the CO2 capture in the ethaline (1ChCl:2E), reline (1ChCl:2U), and glyceline (1ChCl:2G) solvents. Furthermore, the effect of water addition also was simulated in the 2.5 and 5 % concentrations. The MD simulations indicated that the AgNP presence in the three solvents occasioned increased hydrogen bonds (HB) between the CO2 gas and species acting as hydrogen bond donors (HBD), resulting in a reduction of interaction potential values for this group, resulting in improvement of CO2 process capture, especially for the AgNP-reline-CO2 system. Furthermore, the structural analysis from MD simulations suggested that ethylene glycol and urea are the key species in the CO2 capture process for the AgNP-ethaline-CO2 and AgNP-reline-CO2 systems, respectively. For the AgNP-glyceline-CO2 system, the structural analysis indicates that the AgNP is the key species in the CO2 process capture. Analyzing the increase in the water effect, it was observed that the CO2 capture process worsened, especially with the highest water concentration.

Directed design of amorphous metal-organic frameworks for efficient and selective removal of Cu(II) from wastewater

Cu(II) is an essential trace element for the human body, but excessive concentrations in water or the human body can cause irreparable harm to ecosystems and human health. In this study, an amorphous metal-organic frameworks adsorbent (DKTA-MOF) was designed and synthesized using a hydrothermal method for the efficient and selective removal of Cu(II) from water. Various factors affecting the adsorption performance of DKTA-MOF were investigated, including solution pH, reaction time, initial concentration of Cu(II), temperature, coexisting ions, and the number of adsorption-desorption cycles. The experimental results indicate that the maximum adsorption capacity of DKTA-MOF is 160.5 mg/g at 318 K, and the optimal adsorption pH is 5. The adsorption process of Cu(II) by DKTA-MOF follows the pseudo-second-order (PSO) kinetic and the Langmuir isotherm models, indicating that the process mainly involves single-layer chemisorption. The adsorption process is spontaneous, driven by both electrostatic attraction and the sharing of lone pair electrons. DKTA-MOF demonstrates highly efficient and selective removal of Cu(II) in the presence of coexisting ions and maintains a high adsorption capacity after six cycles. Furthermore, the strategies and methods adopted in this design provide new perspectives for the removal of metal ions in wastewater.