Search Results (15)

Deep eutectic solvents (DESs) are environmentally friendly solvents formed by combining hydrogen bond donors and acceptors, resulting in a eutectic mixture with a lower melting point than the individual components. While there is extensive research on the electrochemical synthesis of platinum nanoparticles in DESs, to the best of our knowledge, there are no studies on the chemical reactivity of platinum(II) complexes in these systems. This study investigates the simple model reaction between K₂PtCl₄ and ethylenediamine (en), exploring the behaviour in DES environment, to optimize the synthesis of simple cisplatin-like platinum compounds with the potential objective of improving the traditional methods, decreasing the number of steps required for obtaining target compounds and reducing chemical waste. The reactions were performed in two hydrophilic DESs: choline chloride:glycerol 1:2 (glyceline, GL) and choline chloride:ethylene glycol 1:2 (ethaline, EG). The experiments, conducted in a 70% (v/v) DES and 30% 1:1 H₂O/D₂O mixture to allow for direct NMR analysis, revealed that en quickly formed [PtCl₂(en)], which further reacted to produce [Pt(en)₂]Cl₂. Reaction products were characterised by 1D (¹H and ¹⁹⁵Pt{¹H}) and 2D ([¹H,¹³C]-HSQC and [¹H,¹⁵N]-HSQC) NMR experiments. The discolouration of solutions, due to the consumption of K₂PtCl₄, and the precipitation of the purple Magnus salt [Pt(en)₂][PtCl₄] occurred over time. The main observed difference between the two solvent mixtures was the slower reactivity in glyceline, due to the much higher viscosity of the solution. Diffusion-ordered spectroscopy (DOSY) indicated lower water mobility in DES mixtures than pure water, with the reaction products closely associated with DES molecules. Full article

Sulfamethazine (SM2), a prevalent sulfonamide antibiotic, is commonly detected as an environmental pollutant. Microbial degradation serves as an important approach to treating SM2 contamination. In this study, an SM2-degrading strain, identified as Bacillus cereus J2, was isolated from the activated sludge that had been cultured using SM2 as the exclusive carbon source, which demonstrated exceptional degradation capabilities. Under optimized conditions (30 °C, initial OD600 = 0.1, pH = 8), strain J2 completely degraded 50 mg/L SM2 within 36 h. The strain also showed high degradation efficiency for other sulfonamides, such as sulfamethoxazole and sulfadiazine, and could grow normally in a mixed system containing these compounds. The growth kinetics with SM2 as the exclusive carbon source conformed well to the Haldane model (R² = 0.925), revealing that the strain’s maximum specific growth rate was determined to be 0.066 h⁻¹ (µ_max) at an initial SM2 concentration of 51.35 mg/L. Seven intermediate degradation products were identified using TQ-LCMS analysis, suggesting three potential degradation pathways for SM2. These findings suggest that Bacillus cereus J2 holds significant promise for the bioremediation of SM2-contaminated environments. Full article

Atmospheric volatile organic compounds (VOCs), such as olefins and aromatics, released from synthetic chemical pesticide sprays can increase regional air pollution, public health risks, and food security risks. However, significant uncertainties remain regarding the measurement methods and chemical profiles of VOC emissions. Using an agricultural city, Changchun City in Northeast China, as a case study, we quantified real-time concentration and composition data based on online monitoring instruments for the year 2023. This study optimized data collection methods for emission factors and activity levels and developed a high-precision emission inventory of VOCs in pesticides at the city scale. The emission factors for VOCs from the seven categories of pesticides were estimated as follows: 78 g/kg (nicosulfuron and atrazine, oil-dispersible [OD] and suspension emulsion [SE], respectively), 4 g/kg (chlorpyrifos and indoxair conditioningarb, suspension concentrate [SC]), 5 g/kg (fluopicolide and propamocarb hydrochloride, SC), 217 g/kg (MCPA-dimethylammonium, aqueous solution [AS]), 34 g/kg (glyphosate, AS), 575 g/kg (beta-cypermethrin and malathion, emulsifiable concentrate [EC]), and 122 g/kg (copper abietate, emulsion in water [EW]), depending on the pesticide formulation components and formulation types. The orchard insecticide exhibited the highest emission factors among all pesticides owing to its emulsifiable concentrate formulation and 80% content of inactive ingredients (both factors contribute to the high content of organic solvents in the pesticide). The major components of VOC emissions from pesticide spraying were halocarbons (27–44%), oxygenated VOCs (OVOCs) (25–38%), and aromatic hydrocarbons (15–28%). The total VOC emissions from pesticide spraying in the Changchun region accounted for 10.6 t, with Yushu City contributing 28% of the VOC emissions and Gongzhuling City and Dehui City contributing 18.7% and 16.0%, respectively. Herbicides were the main contributors to VOC emissions because of their high emission factors and extensive use in fields (used for spraying maize and rice, the main crops in Changchun City). May and June exhibited the highest VOC emissions from pesticide application, with May accounting for 57.0% of annual pesticide emissions, predominantly from herbicides (95.1%), followed by insecticides (4.9%). June accounted for 30.1% of the annual pesticide emissions, with herbicides being the largest contributor of VOC emissions. An emission inventory of VOC with a monthly scale and spatial grid resolutions of 0.083° and 0.5° in 2023 was developed. These emission factors and inventories of pesticide applications provide valuable information for air quality modeling. This study also provides an important scientific basis for enhancing regional air quality and mitigating the environmental impact of pesticide use in major grain-producing areas. Full article

The species of the adaptive male–female sex ratio has different effects on the bio-community. This paper is aimed at figuring out these effects through mechanism analysis and Ordinary Differential Equation (ODE). Hence, the ODE environmental model is created by combining the Lotka–Volterra model, the interspecific model, and other external factors. The stability is used to characterize these effects. According to this model, effects on bio-community stability under different male–female sex ratios are roughly observed. By innovatively considering different living environments during the species’ lifecycle, the ODE environmental model is optimized, and the effects of different male–female sex ratios on the bio-community are further analyzed by phase-track maps and relative standard deviation. It is found that there are different findings and features in resource-rich and resource-scarce living environments during the lifecycle. Meanwhile, bio-communities in these two types of environments are in a stable state based on different male–female sex ratios. Based on these findings, directive opinions can be used to manage and help relevant bio-communities. Full article

This article explores the cutting-edge advancement of gypsum or cement building boards infused with shape-stabilized n-octadecane, an organic phase change material (PCM). The primary focus is on improving energy efficiency and providing electromagnetic interference (EMI) shielding capabilities for contemporary buildings. This research investigates the integration of these materials into construction materials, using red-mud carbon foam (CCF) as a stabilizer for n-octadecane (OD@CCF). Various analyses, including microstructural examination, porosity, and additive dispersion assessment, were conducted using X-ray microtomography and density measurements. Thermal conductivity measurements demonstrated the enhancement of composite boards as the OD@CCF content increased, while mechanical tests indicated an optimal additive content of up to 20%. The thermally regulated capabilities of these advanced panels were evaluated in a custom-designed room model, equipped with a homemade environmental chamber, ensuring a consistent temperature environment during heating and cooling cycles. The incorporation of OD@CCF into cement boards exhibited improved thermal energy storage properties. Moreover, the examined composite boards displayed efficient electromagnetic shielding performance within the frequency range of 3.2–7.0 GHz, achieving EMI values of approximately 18 and 19.5 dB for gypsum and cement boards, respectively, meeting the minimum value necessary for industrial applications. Full article

Due to the increasing demand for green processes in renewable energy production, the extracellular Bacillus subtilis B-1-4 lipase was used as a biocatalyst for producing biodiesel from waste cooking oil. Response surface methodology was employed for the optimization of enzyme production. Lipase activity was modeled with a quadratic function of four factors that primarily influence the culture medium. Thanks to this model, an optimal lipase activity of 1.7 ± 0.082 U/mL was achieved with the best culture medium composition: 16 g/L of tryptone, 15 g/L of yeast extract, 15 g/L of NaCl, and a 0.15 initial optical density at 600 nm (OD600 nm). The maximal lipase activity was measured at 45 °C and pH 8, using para-nitrophenyl palmitate as a substrate. The enzyme maintained above 94% and 99% of its initial activity at temperatures ranging from 40 to 50 °C and at pH 8, respectively. Moreover, it exhibited a higher residual activity than other Bacillus lipases in the presence of organic solvents. Residual activities of 86.7% and 90.2% were measured in the presence of isopropanol and ethanol, respectively. The lipase was immobilized by adsorption onto CaCO₃ powder. FT-IR and SEM were used to characterize the surface-modified support. After immobilization, a lipase activity of 7.1 U/mg of CaCO₃ was obtained. Under the optimized conditions, the highest biodiesel yield of 71% was obtained through the transesterification of waste cooking oil using the CaCO₃-immobilized Bacillus subtilis lipase. This research reveals a method for the utilization of waste cooking oil for biodiesel production using an efficient immobilized thermostable lipase, providing environmental and economic security. Full article

Biosynthetic gold nanoparticles (bAuNPs) present a promising avenue for enhancing bio-compatibility and offering an economically and environmentally responsible alternative to traditional production methods, achieved through a reduction in the use of hazardous chemicals. While the potential of bAuNPs as anticancer agents has been explored, there is a limited body of research focusing on the crucial physicochemical conditions influencing bAuNP production. In this study, we aim to identify the optimal growth phase of Pseudomonas aeruginosa cultures that maximizes the redox potential and coordinates the formation of bAuNPs with increased efficiency. The investigation employs 2,6-dichlorophenolindophenol (DCIP) as a redox indicator. Simultaneously, we explore the impact of temperature, pH, and incubation duration on the biosynthesis of bAuNPs, with a specific emphasis on their potential application as antitumor agents. Characterization of the resulting bAuNPs is conducted using ATR-FT-IR, TEM, and UV-Vis spectroscopy. To gain insights into the anticancer potential of bAuNPs, an experimental model is employed, utilizing both non-neoplastic (HPEpiC) and neoplastic (PC3) epithelial cell lines. Notably, P. aeruginosa cultures at 9 h/OD600 = 1, combined with biosynthesis at pH 9.0 for 24 h at 58 °C, produce bAuNPs that exhibit smaller, more spherical, and less aggregated characteristics. Crucially, these nanoparticles demonstrate negligible effects on HPEpiC cells while significantly impacting PC3 cells, resulting in reduced viability, migration, and lower IL-6 levels. This research lays the groundwork for the development of more specialized, economical, and ecologically friendly treatment modalities. Full article

Lead (Pb) is well known for the containment of soil surfaces. In the last few decades, phytoremediation has been the most ideal technology to extract Pb from soil, involving numerous chemical reactions and cost analysis. The aim of this study is to model and to optimize Pb extraction from the contaminated soil via Pelargonium hortorum by comparing two modeling approaches: response surface methodology (RSM) and artificial neural networks (ANNs) with the genetic algorithm (GA). To determine the significance of the proposed solution, in vitro essays were performed to check the Pb tolerance of bacterial strains (NCCP 1844, 1848, 1857, and 1862), followed by the co-application of bacteria and citric acid on a Pb hyperaccumulator (Pelargonium hortorum L.) on Murashige and Skoog (MS) agar medium. Afterwards, a pot culture experiment was performed to optimize Pb extraction competency from Pb-spiked (0 mg kg⁻¹, 500 mg kg⁻¹, 1000 mg kg⁻¹, and 1500 mg kg⁻¹) soil by Pelargonium hortorum L., to which citric acid (5 and 10 mmol L⁻¹) and Microbacterium paraoxydance (1 and 1.5 OD) were applied. Plants were harvested at 30, 60, and 90 day intervals, and they were analyzed for dry biomass and Pb uptake characteristics. The maximum Pb extraction efficiency of 86.0% was achieved with 500 mg kg⁻¹ soil Pb for 60 days. Furthermore, RSM, based on the Box–Behnken design (BBD) and the ANN-based Levenberg–Marquardt Algorithm (LMA), were applied to model Pb extraction from the soil. The significance of the predicted values from RSM and LMA were close to 36.0% and 86.05%, respectively, compared to the laboratory values. The comprehensive evaluation of these findings encouraged the accuracy, reliability, and efficiency of the ANN for the optimization process. Therefore, experimental results showed that ANN is an accurate technique to optimize an integrated phytoremediation system for sustainable Pb removal, besides being environmentally friendly and potentially cost-effective. Full article

In recent years, liner-shipping companies have faced a traditional trade-off between cost and emission (CO₂ and SO_X) reduction. This study considers this element to construct a liner-shipping network design model which includes a package-cargo transport plan, route allocation, and route design. The objective is to maximize profit by selecting the ports to be visited, the sequence of port visits, the cargo flows between ports, and the number/operating speeds of vessels. In addition, emission control areas (ECAs) exist in the liner network. With reference to the idea of the column generation algorithm, this study proposed a heuristic algorithm based on empirical data through a real case calculation and selected the optimal scheme, which is in-line with both economic and environmental benefits. The results show that the model and optimization method are feasible and provide an effective solution for the liner network design of shipping companies, while also considering environmental factors. In addition, the effects of the number of ECAs, inter-port origin-destination (OD) demand, freight rate, fuel price, and carbon prices on the design of transport networks are discussed to provide a reference for the operation of shipping companies and government decision-making. Full article

The type of single-slope solar greenhouse is mainly used for vegetable production in China. The coupling of heat storage and release courses and the dynamic change in the outdoor weather parameters momentarily affect the indoor environment. Due to the high cost of small weather stations, the environmental parameters monitored by the nearest meteorological stations are usually used as outdoor environmental parameters in China. In order to accurately predict the solar greenhouse and crop water demand, this paper proposes three deep learning models, including neural network regression (DNNR), long short-term memory (LSTM), and convolutional neural network-long- short-term memory (CNN-LSTM), and the hyperparameters of three models were determined by orthogonal experimental design (OD). The temperature and relative humidity monitored by the indoor sensors and outdoor weather station were taken as the inputs of models, the temperature and relative humidity 3, 6, 12 and 24 h in advance were taken as the output, 16 combinations of input and output data of two typical solar greenhouses were trained separately by three deep learning models, those models were trained 144, 144 and 288 times, respectively. The best model of three type models at four prediction time points were selected, respectively. For the forecast time point of 12 h in advance, the errors of the best LSTM and CNN-LSTM models in two greenhouses were all smaller than the DNNR models. For the three other time points, the results show that the DNNR models have excellent prediction accuracy among the three models. The maximum and minimum temperature, relative humidity, and ET_o were also accurately predicted using the corresponding optimized models. In sum, this study provided an optimized deep learning prediction model for environmental parameters of greenhouse and provides technical support for irrigation decision-making and water allocation. Full article

Microplastics (MP) are a global environmental problem because they persist in the environment for long periods of time and negatively impact aquatic organisms. Possible solutions for removing MP from the environment include biological processes such as bioremediation, which uses microorganisms to remove contaminants. This study investigated the biodegradation of polystyrene (PS) by two bacteria, Bacillus cereus and Pseudomonas alcaligenes, isolated from environmental samples in which MPs particles were present. First, determining significant factors affecting the biodegradation of MP-PS was conducted using the Taguchi design. Then, according to preliminary experiments, the optimal conditions for biodegradation were determined by a full factorial design (main experiments). The RSM methodology was applied, and statistical analysis of the obtained models was performed to analyze the influence of the studied factors. The most important factors for MP-PS biodegradation by Bacillus cereus were agitation speed, concentration, and size of PS, while agitation speed, size of PS, and optical density influenced the process by Pseudomonas alcaligenes. However, the optimal conditions for biodegradation of MP-PS by Bacillus cereus were achieved at γ_MP = 66.20, MP size = 413.29, and agitation speed = 100.45. The best conditions for MP-PS biodegradation by Pseudomonas alcaligenes were 161.08, 334.73, and 0.35, as agitation speed, MP size, and OD, respectively. In order to get a better insight into the process, the following analyzes were carried out. Changes in CFU, TOC, and TIC concentrations were observed during the biodegradation process. The increase in TOC values was explained by the detection of released additives from PS particles by LC-MS analysis. At the end of the process, the toxicity of the filtrate was determined, and the surface area of the particles was characterized by FTIR-ATR spectroscopy. Ecotoxicity results showed that the filtrate was toxic, indicating the presence of decomposition by-products. In both FTIR spectra, a characteristic weak peak at 1715 cm⁻¹ was detected, indicating the formation of carbonyl groups (−C=O), confirming that a biodegradation process had taken place. Full article

Commonly used as biological chemosensors in toxicity assays, Vibrio fischeri bacteria were systematically characterized using complementary physicochemical and biological techniques to elucidate the evolution of their properties under varying environmental conditions. Changing the pH above or below the optimal pH 7 was used to model the long-term stress that would be experienced by V. fischeri in environmental toxicology assays. The spectral shape of bioluminescence and cell-surface charge during the exponential growth phase were largely unaffected by pH changes. The pH-induced modulation of V. fischeri growth, monitored via the optical density (OD), was moderate. In contrast, the concomitant changes in the time-profiles of their bioluminescence, which is used as the readout in assays, were more significant. Imaging at discrete timepoints by scanning electron microscopy (SEM) and helium-ion microscopy (HIM) revealed that mature V. fischeri cells maintained a rod-shaped morphology with the average length of 2.2 ± 1 µm and diameter of 0.6 ± 0.1 µm. Detailed morphological analysis revealed subpopulations of rods having aspect ratios significantly larger than those of average individuals, suggesting the use of such elongated rods as an indicator of the multigenerational environmental stress. The observed modulation of bioluminescence and morphology supports the suitability of V. fischeri as biological chemosensors for both rapid and long-term assays, including under environmental conditions that can modify the physicochemical properties of novel anthropogenic pollutants, such as nanomaterials and especially stimulus-responsive nanomaterials. Full article

The transition to the use of supercritical carbon dioxide as a working fluid for power generation units will significantly reduce the equipment′s overall dimensions while increasing fuel efficiency and environmental safety. Structural and parametric optimization of S–CO₂ nuclear power plants was carried out to ensure the maximum efficiency of electricity production. Based on the results of mathematical modeling, it was found that the transition to a carbon dioxide working fluid for the nuclear power plant with the BREST–OD–300 reactor leads to an increase of efficiency from 39.8 to 43.1%. Nuclear power plant transition from the Rankine water cycle to the carbon dioxide Brayton cycle with recompression is reasonable at a working fluid temperature above 455 °C due to the carbon dioxide cycle′s more effective regeneration system. Full article

In this study, oxidative desulfurization (ODS) of modeled and real oil samples was investigated using manganese-dioxide-supported, magnetic-reduced graphene oxide nanocomposite (MnO₂/MrGO) as a catalyst in the presence of an H₂O₂/HCOOH oxidation system. MnO₂/MrGO composite was synthesized and characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analyses. The optimal conditions for maximum removal of dibenzothiophene (DBT) from modeled oil samples were found to be efficient at 40 °C temperature, 60 min reaction time, 0.08 g catalyst dose/10 mL, and 2 mL of H₂O₂/formic acid, under which MnO₂/MrGO exhibited intense desulfurization activity of up to 80%. Under the same set of conditions, the removal of only 41% DBT was observed in the presence of graphene oxide (GO) as the catalyst, which clearly indicated the advantage of MrGO in the composite catalyst. Under optimized conditions, sulfur removal in real oil samples, including diesel oil, gasoline, and kerosene, was found to be 67.8%, 59.5%, and 51.9%, respectively. The present approach is credited to cost-effectiveness, environmental benignity, and ease of preparation, envisioning great prospects for desulfurization of fuel oils on a commercial level. Full article

The expansion of urban space makes citizens more dependent on cars, resulting in various urban environmental and traffic problems. Advocating low-carbon travel and building a sustainable low-carbon city are the major trends of urban development. Many scholars have pointed out that the urban spatial environment will lead residents to change their travel modes, but the residents’ travel patterns will also have an impact on the urban spatial layout. Based on the interaction between the two, most of the studies have been evaluated and studied from the level of rail transit and normal bus transit. The traffic volume level of trams lies between the rail transit and the normal public transit. However, the research and discussion on the relationship between the surrounding land use and residents’ travel behaviors are not yet perfect domestically. This paper takes Nanjing Chilin Tram Line 1 in China as the research object, combines the research of the the social attributes of the passengers who live along the tram line and the psychological accessing threshold of different travel purposes, provides analysis and evaluations of the coupling degree between the present situation of land use around its various stations and the residents’ actual travel demand with the measure of accessibility. The traffic volume level of trams lies between the rail transit and the normal public transit. However, the research and discussion on the relationship between the surrounding land use and residents’ travel behaviors are not yet perfect domestically. Taking Nanjing Chilin Tram Line 1 in China as the research object, this paper combines the research of the the social attributes of the passengers who live along the tram line and the psychological accessing threshold of different travel purposes. Furthermore, based on the measure of accessibility, it provides the analysis and evaluations of the coupling degree between the present situation of land use around its various stations and the residents’ actual travel demand. The research method of this paper is divided into three parts. Firstly, based on the questionnaire and OD survey, the coupling degree between the type of the station along the tram line and the distribution of passenger flow and the purpose of passenger travel is analyzed. Secondly, the KLP model is used to calculate and determine the effective influence range of the tram through the critical accessing distance for pedestrians psychologically. Based on different psychological thresholds for different purposes, the land use index within the influence range of the station is evaluated and analyzed, and the controlled circle of land use around each type of station is defined. Finally, the coupling degree between the actual land use status in each circle and residents’ psychological threshold with different purposes is analyzed, and the optimization strategy is proposed from the coupling degree between the overall station type & passenger flow along the line and the land use layout around the station & the residents’ psychological threshold. Full article