Environmental Problems Research Articles

Structural forming of soil composites using as a pavement subgrade strengthening

The article substantiates the possibility of obtaining composite materials with improved functional properties to strengthen the subgrade, containing technogenic soil stabilized by an additive based on a gelling polymer. The introduction of technogenic soils into composites will not only reduce the consumption of expensive materials, but also solve a complex of acute environmental problems. Composite materials can be used in the construction of structural layers of road pavements, foundations of buildings and structures, sites for various purposes, for the prevention and elimination of defects in the foundations of engineering structures during their construction, reconstruction and repair, including in permafrost areas. Stabilized technogenic soils are more durable, frost-resistant and waterproof, which makes them applicable for creating impervious curtains in hydraulic structures and sealing storage facilities for hazardous substances. The cryogenic effect on a composite material allows one to vary its properties within a wide range and modify its macroporous structure. Studying the process of structure formation of the resulting organic-inorganic materials, consisting of macromolecules of high-molecular substances and inorganic inclusions that have undergone cryogenic treatment, will make it possible to specifically regulate their performance characteristics. The best values of strength characteristics were obtained for samples with a stabilizing additive concentration of 100g/l. The resulting composite materials are hydrophobic, frost-resistant, characterized by a compressive strength of 2.3-6.5MPa and a thermal conductivity of 0.19-0.20W/(m·K). Data from differential scanning calorimetry and thermogravimetry and IR spectroscopy revealed that the binding of mineral particles by a stabilizing additive occurs due to the formation of organomineral complexes with the participation of clay minerals and the restructuring of hydration shells. SEM data indicate that crystallinity zones formed due to hydrogen bonds of hydroxyl groups of neighboring polymer chains can participate in the formation of the composite structure. An increase in the number of cryogenic treatment cycles promotes additional structuring and strengthening of the polymer phase due to the formation of additional nodes of the supramolecular network, ordering of crystallinity zones and the appearance of compacted areas in the structure. Computed X-ray tomography revealed an increase in the density of the composite upon drying, which helps to increase its strength characteristics. The structure of the sample is characterized by heterogeneity of the pore space, which is characterized by the presence of both fine-porous and large-porous regions, which determines its thermophysical properties.

In Ukrainian

An important environmental problem is the removal of contaminants and the purification of domestic and industrial water from pollutants of various nature. There is a separate issue of cleaning the effluents of pharmaceutical enterprises. Various chemical and physical methods are used to solve these problems, such as settling, coagulation, filtration, and sorption techniques. Adsorption with using efficient and reusable adsorbents is the most effective and cheap. In recent years special attention has been paid to the use of sorption materials based on hydrolysis lignin, which has a high sorption activity in relation to ions of some heavy metals, dyes, organic compounds and pharmaceuticals. The use of lignin as an adsorbent simultaneously solves two problems: the disposal of paper production waste and the purification of sewage from various types of pollutants. The aim of this work was to study the sorption properties of hydroylysis lignin in aqueous solution in relation to some medical substances of different chemical nature, existing in solution in cationic, anionic or neutral forms. The point of zero charge of hydrolysis lignin was determined, which is equal to рНPZC = 4.95. The adsorption of rivanol, proflavin, doxorubicin, levofloxacin, furacilin, and salicylic acid by hydrolysis lignin was studied as dependence on the pH of the solutions and the concentration of adsorbates. It was found that adsorption largely depends on the structure of the pharmaceuticals and the pH values of the solutions. It is shown that the studied medical compounds, which exist in the solution in the form of cations, are adsorbed the best (rivanol, proflavin, doxorubicin). Adsorption of these substances occurs mainly due to electrostatic interaction with negatively charged surface groups. Adsorption of anionic form (salicylic acid) is the smallest and is observed only at quite low pH values. Levofloxacin is adsorbed mainly in the form of zwitter ions, and furacilin is in neutral form. The adsorption of these both compounds occupies an intermediate value of adsorption amount. The obtained adsorption isotherms are well lined up in Langmuir coordinates. Quantitative parameters of adsorption values - of maximum adsorption and equilibrium constants were calculated. Quite high values of these parameters indicate that hydrolysis lignin can be used as an adsorbent for the removal of these pharmaceuticals.

The Role of Certain Knowledge Management Processes in Improving Environmental Sustainability: An Exploratory Study of the Opinions of a Sample of Employees in the Iron and Steel Company in Mosul

The research aims to determine the relationship between some knowledge management processes, how to apply and invest them properly, and what is their active role in improving environmental sustainability. The needs of the individual and society The goal of sustainable development is to develop business by meeting the needs of the present without compromising the ability of future generations, as the world faces the danger of environmental degradation, so development needs must not be abandoned and operations aimed at achieving sustainability must be conducted Environmental in business and its development, for example, how to recycle and others while preserving the environment because it is part of a multidimensional perspective related to economic, cultural and health aspects. This type of sustainability creates a safe and beautiful environment that seeks to reduce environmental impacts that have a role in the movement towards sustainable development by finding solutions to environmental problems. Organizations should consider a set of procedures and policies related to regular management and continuous improvement of environmental performance, and the analytical descriptive approach was relied upon In the completion of the research, a questionnaire was designed on a sample of (60) individuals working in the iron and steel company, and the data was analyzed through statistical programs using the program (spss) and access to the results. In light of it, the research presented a set of proposals for the field under study.

The Effects of Schooling Rates and Income Levels on Energy Consumption in Households: A Panel Data Analysis on OECD Countries

AbstractWhile energy consumption affects many different areas, it is also affected by many different factors. Therefore, policies aiming to reduce energy consumption gain a multidimensional feature. Income level and education play an important role in the success of these policies. Because as the income and education levels of individuals increase, the success rate of policies aiming to reduce energy consumption is higher. In this way, while energy consumption is reduced or used more efficiently, environmental problems are prevented. In this study, the effects of average schooling rate and income level on energy consumption in residences were investigated. For this purpose, the panel data analysis was used within the scope of the annual data of 19 OECD member countries for the 1990–2019 period. As a result of the analysis, a cointegration relationship was detected between the variables and long-term coefficients and error correction coefficient and short-term coefficients were obtained with the Augmented Mean Group (AMG) estimator. The findings show that the long-term average schooling rate has a negative effect on energy consumption in households, but income level has a positive effect on a panel basis. On the other hand, it was also found that the error correction mechanism works and that the income level has a positive effect on the energy consumption in the households in the short term, but the average schooling rate does not have a significant effect on the energy consumption in the households in the short term.

Commercial Small-Scale Horizontal and Vertical Wind Turbines: A Comprehensive Review of Geometry, Materials, Costs and Performance

The effective exploitation of renewable energy sources is one of the most effective solutions to counter the energy, environmental and economic problems associated with the use of fossil fuels. Small-scale wind turbines (converting wind energy into electric energy with a power output lower than 50 kW) have received tremendous attention over the past few decades thanks to their reduced environmental impact, high efficiency, low maintenance cost, high reliability, wide wind operation range, self-starting capability at low wind speed, limited installation space, reduced dependence on grid-connected power and long transmission lines, low capital costs, as well as the possibility to be installed in some urban settings. However, there are significant challenges and drawbacks associated with this technology from many different perspectives, including the significant discrepancy between theoretical performance data provided by the manufacturers and real field operation, that need to be investigated in greater depth in order to enable a more widespread deployment of small-scale wind turbines. In this review, a complete and updated list of more than 200 commercially available small-scale horizontal and vertical wind turbine models is provided and analysed, detailing the corresponding characteristics in terms of the number and material of blades, start-up wind speed, cut-in wind speed, cut-out wind speed, survival wind speed, maximum power, noise level, rotor diameter, turbine length, tower height, and specific capital cost. In addition, several scientific papers focusing on the experimental assessment of field performance of commercially available small-scale horizontal and vertical wind turbines have been reviewed and the corresponding measured data have been compared with the rated performance derived from the manufacturers’ datasheets in order to underline the discrepancies. This review represents an opportunity for the scientific community to have a clear and up-to-date picture of small-scale horizontal as well as vertical wind turbines on the market today, with a precise summary of their geometric, performance, and economic characteristics, which can enable a more accurate and informed choice of the wind turbine to be used depending on the application. It also describes the differences between theoretical and in-situ performance, emphasizing the need for further experimental research and highlighting the direction in which future studies should be directed for more efficient design and use of building-integrated small-scale wind turbines.

Assessing Reliability, Resilience and Vulnerability of Water Supply from SuDS

In recent decades, the impacts of urbanization on the hydrological cycle have led to an increase in the frequency and magnitude of urban flooding events, and this is also amplified by the effects of climate change. Sustainable Drainage Systems (SuDS) provide a revolutionary change in this field, improving the sustainability and resilience of cities. This research explores the integration of different SuDS with the aim of significantly reducing both the flow volume and celerity of floods in a residual urban catchment area of the metropolitan city of Querétaro (Mèxico), where extreme rainfall frequently occurs. This catchment is a representative suburb of urban pressure and environmental degradation problems. Currently, managing storm water under climate uncertainty through a multi-disciplinary approach is a major concern in this urban area. A 1D–2D coupling model of shallow water equations, the finite volume method, an unstructured meshing method, and a hybrid parallel computing application defined the optimal configuration of SuDS at catchment scale to reduce the flood vulnerability in Querétaro. Specifically, in this paper, we explore the management issues of the proposed SuDS configuration that acts as a water resource system with multiple purposes. A generic simulation model called MODSIM was applied to simulate the designed urban drainage system under a balanced IPCC future climate scenario in terms of reliability, resilience and vulnerability against water scarcity. The proposed hierarchical Reliability–Resilience–Vulnerability approach appears to be effective in evaluating the system performance, showing that the complete satisfaction of non-essential water uses in Querétaro can be assured at a 65% rate of reliability for a large range of reservoir storage conditions.

Poprawa zdolności sorpcyjnej i zastosowania biosorbentu poprzez immobilizację

The water contamination by toxic metal ions is a worldwide environmental problem. High concentrations are hazardous for all living organisms, causing many disorders and diseases and ecological damages to the surroundings. Biosorption is an innovative technology that employs inactive and dead biomass (bacteria, fungi, algae, biowaste) for the recovery of metals from aqueous solutions. Sulphate-reducing bacteria utilization is one of the options how to prepare applicable sorbent which removes metal ions from water. This material is created as a consequence of bacteria metabolism in anaerobic environment. The use of freely suspended biomass is often impractical and has some disadvantages. In contrast to this, application of immobilized biomass shows more benefits including increased mechanical strength, resistance to chemical environment, easy separation of cells and effluents, high biomass performance and repeated use in many adsorption/desorption cycles. Cell entrapment is the most widely used method for immobilization. In this technique, the cells are enclosed in a polymeric matrix which is porous enough to allow diffusion of substrate to the cells. The aim of this work was to examine and compare the sorption ability of biogenic iron sulphides created by sulphate-reducing bacteria in “free” and “entrapped” form. Precipitates were synthesized in reagent bottles with bacteria culture and growth media Postgate C, at 30 °C during 60 days, subsequently dried and analysed. Prepared samples were immobilized using sodium alginate. Sorption of cadmium from model solutions was realized in 100 ml Erlenmeyer flasks, with sorbent dose 1 g/l, during 24 hours. During experiments, the samples showed a satisfying stability and maximum adsorption capacity achieved 38 mg/g. The results refer to good sorption properties of immobilized samples and their potential for further practical use.

In situ growth of HKUST-1 on electrospun polyacrylonitrile nanofibers/regenerated cellulose aerogel for efficient methylene blue adsorption

Dyes, as organic pollutants, are causing increasingly severe environmental problems. Metal-organic frameworks (MOFs) are considered promising dye adsorbents; however, their application is limited due to their powder or solid particle forms and limited reusability. Therefore, this study proposes an innovative approach to develop a novel MOF-based composite aerogel, specifically a HKUST-1/polyacrylonitrile nanofibers/regenerated cellulose (HKUST-1/PANNs/RC) composite aerogel adsorbent, for the adsorption of pollutants in water. This adsorbent was successfully prepared using a simple method combining covalent crosslinking, quick freezing, freeze-drying, in-situ growth synthesis, and solvothermal techniques. The HKUST-1/PANNs/RC composite aerogel exhibits a significantly large specific surface area, which is approximately 64 times greater than that of PANNs/RC (10.45 m2·g−1), with a specific surface area of 669.9 m2·g−1. The PANNs serve as a support framework, imparting excellent mechanical properties to the composite aerogel, enhancing its overall stability and recoverability. Additionally, the composite aerogel contains numerous -COOH and -OH groups on its surface, providing strong acid resistance and facilitating interactions with pollutant molecules through electrostatic interactions, π-π conjugation, n-π* interactions, and hydrogen bonding, thereby promoting the adsorption process. Using methylene blue (MB) as a probe molecule, the study results demonstrate that the HKUST-1/PANNs/RC composite aerogel has an adsorption capacity of 522.01 mg·g−1 for MB (25 h), exhibiting excellent adsorption performance. This composite aerogel shows great potential for application in water pollution control.

A Feasibility Study of Bio-Briquettes Production from the Skin and Epidermis Layer of Cassava (Manihot esculenta) as An Alternative Energy

Unprocessed leftover cassava wastes from the home industries in Pomahan Village in Bojonegoro, East Java, has become a serious problem as a pollutant to the environment. This study examined the quality of bio-briquettes made from cassava skin waste with its epidermis starch as an adhesive agent, or binder. The aim is to assess the quality of the bio-briquettes for alternative energy sources and their suitability from an economic point of view. The utilized research method was a descriptive quantitative approach by measuring water and ash content, calorific value test, and economic feasibility calculation. The results indicated that the highest calorific value of 5337.83 cal/g was obtained from a bio-briquette mix of 50 g cassava skin with 5% epidermis starch binder. This bio-briquette also possesses the lowest water and ash contents of 2.75 and 8%, respectively, compared to other mixtures. The economic feasibility calculation showed a BEP value of 423 kg/ month, B/C Ratio of 6.14-fold, ROI of 30%, and PBI of 0.2 years. In conclusion, cassava-based bio-briquettes are economically promising and environmentally friendly due to their biomass property and help to tackle the environmental problem due to the cassava waste.

Effect of Corn Stover Ash Reinforced with Cabuya Fiber on the Mechanical Properties of Concrete

Currently, organic wastes are an environmental problem generating pollution, bad odors and accumulation of residues in northern Peru, among these products are corn stover and cabuya, predominant materials in the area. Therefore, this research focuses on determining the effect of optimum temperature and optimum percentage of corn stover ash (CSA) reinforced with different proportions of cabuya fiber (CF) on the mechanical properties of concrete. Two conventional designs of standard concrete called A and B (21 and 28 MPa) were made, to these designs were added percentages of CSA in 7%, 10%, 12% and 15% by substitution of the weight of cement to determine the optimum percentage, which was reinforced with percentages of cabuya fiber in 0.5%, 1%, 1.5% and 2% in volume of the concrete. The results showed that the optimum mix was A/B+7CSA, evidencing an improvement in compressive strength of 2.7% as opposed to the optimum CSA +CF hybrid mix, where it was observed that its mechanical properties of compressive strength, tensile strength, flexural strength and static modulus of elasticity decreased to 15.8%, 11.30%, 5.14% and 10.5%, respectively. It is concluded that corn stover ash reinforced with cabuya fiber does not positively influence the mechanical properties of concrete; however, it is an environmentally sustainable alternative to be used in non-structural concrete.

Innovative and efficient integrations of desalination plants coupled absorption, adsorption, and humidification-dehumidification desalination units employing external heat recovery techniques

Thermal desalination technologies have been developed recently to solve some pressing problems, such as high energy expenditure, increasing fuel costs, and environmental problems related to conventional plants. However, these technologies still need to be enhanced in terms of water production and gain output ratio (GOR). This paper presents innovative and efficient combined thermal desalination plants consisting of absorption (ABDS), adsorption (ADDS), and humidification-dehumidification (HDH) desalination units to enhance energy utilization, water production, and overall system performance. Four innovative combined desalination plants employing different external heat recovery scenarios are presented and compared. The result from each scenario is evaluated and compared with those of the standalone ABDS and with other studies found in the literature at the same heat source temperatures. The heat source is mainly utilized to drive the ABDS plant. The ADDS and HDH are driven by the heat rejection from the ABDS components with different external heat recovery scenarios. Results illustrated that the maximum freshwater production generated from the proposed scenarios ranges between 1.57 and 2.94 m3.day−1 with a GOR of between 1.38 and 1.75 at 120 °C. Raising heat source temperatures from 55 to 120 °C decreased the improvement in the water productivity from 618.5 to 224 % and decreased the enhancement in the GOR from 222.8 to 99 %. In scenarios where the ADDS and HDH are driven by the heat rejection from the absorption and condensation process of the ABDS, the maximum freshwater production results from the ABDS unit. On the other hand, in scenarios where the ADDS and HDH are driven by the outlet hot water from the ABDS-generator, the maximum freshwater production is obtained from the HDH unit. The finding provided that the proposed innovative scenarios have an effective improvement in overall system performance indicators.

Effects of water replenishment on lake water quality and trophic status: An 11-year study in cold and arid regions

Water replenishment is an important measure for maintaining and improving the aquatic environmental quality of lakes. The problems of water quality deterioration and water shortage can be alleviated by introducing water of higher quality. However, the mechanism of water replenishment in the improvement of the water quality and trophic status of lakes remains unclear. This study investigated water replenishment in Wuliangsuhai Lake (WLSHL) from 2011 to 2021 by collecting seasonal water samples and conducting laboratory analyses. Water replenishment was found to be capable of significantly improving lake water quality and alleviating eutrophication. It is worth noting that single long-term water replenishment measures have limitations in improving the water quality and trophic status. The whole process was divided into three stages according to the water quality and trophic status, namely the buffer period, decline period, and stable period. During the buffer period, the water quality and trophic status showed only slight improvement because of the small amount of water replenishment and the low proportion of higher-quality water from the Yellow River. In the decline period, with increasing water replenishment, the proportion of higher-quality water from the Yellow River gradually increased, leading to the most significant and stable degree of improvement. In the stable period, increases in the amount of water replenishment had little effect on improving the water quality and trophic status, which is attributable to the balance between internal pollutants (lake water–sediment), and the balance between internal-external pollutants (lake water–irrigation return flow + Yellow River water). On the premise of stable water quality, with eutrophication control as the management goal, the optimal water replenishment would be approximately 10.58 ×108 m3. Further necessary measures for solving aquatic environmental problems include the combination of sediment dredging, optimization of the water replenishment route, and implementation of quality management in water replenishment.

Becoming a science teacher in the Anthropocene: scientific knowledge as ‘matters of concern’

ABSTRACT In the Anthropocene, there is a significant need for new ways to educate about science and environmental problems, including climate issues. This article explores Swedish teacher students’ discussions as they envision their future roles as science teachers in the light of the Anthropocene. At the beginning of their science teacher education, the teacher students are not fully immersed in the established discourses of the educational system as in-service teachers. In this study, we consider how these teacher students’ ‘fresh eyes’ bring views of how knowledge (especially chemistry-related knowledge) matters in education and teaching. Through a lecture that centred planetary boundaries and the Great Acceleration as representations of some main scientific models in the field, the teacher students were introduced to the concept of Anthropocene. Five focus group discussions followed this introduction. Thematic analysis reveals how the acquired knowledge of the introductory lesson challenges the students to express ‘matters of concern’ differently: partly considering a personal, everyday level and partly reformulating their role as future science teachers. The interrelation of these positions is also a concern for the concluding discussion. Furthermore, the article discusses these results as both concerns and possibilities for science education, including science teacher education.

Bismuth Film along with dsDNA-Modified Electrode Surfaces as Promising (bio)Sensors in the Analysis of Heavy Metals in Soils.

Heavy metals constitute pollutants that are particularly common in air, water, and soil. They are present in both urban and rural environments, on land, and in marine ecosystems, where they cause serious environmental problems since they do not degrade easily, remain almost unchanged for long periods, and bioaccumulate. The detection and especially the quantification of metals require a systematic process. Regular monitoring is necessary because of seasonal variations in metal levels. Consequently, there is a significant need for rapid and low-cost metal determination methods. In this study, we compare and analytically validate absorption spectrometry with a sensitive voltammetric method, which uses a bismuth film-plated electrode surface and applies stripping voltammetry. Atomic absorption spectroscopy (AAS) represents a well-established analytical technique, while the applicability of anodic stripping voltammetry (ASV) in complicated sample matrices such as soil samples is currently unknown. This sample-handling challenge is investigated in the present study. The results show that the AAS and ASV methods were satisfactorily correlated and showed that the metal concentration in soils was lower than the limit values but with an increasing trend. Therefore, continuous monitoring of metal levels in the urban complex of a city is necessary and a matter of great importance. The limits of detection of cadmium (Cd) were lower when using the stripping voltammetry (SWASV) graphite furnace technique compared with those obtained with AAS when using the graphite furnace. However, when using flame atomic absorption spectroscopy (flame-AAS), the measurements tended to overestimate the concentration of Cd compared with the values found using SWASV. This highlights the differences in sensitivity and accuracy between these analytical methods for detecting Cd. The SWASV method has the advantage of being cheaper and faster, enabling the simultaneous determination of heavy elements across the range of concentrations that these elements can occur in Mediterranean soils. Additionally, a dsDNA biosensor is suggested for the discrimination of Cu(I) along with Cu(II) based on the oxidation peak of guanine, and adenine residues can be applied in the redox speciation analysis of copper in soil, which represents an issue of great importance.

Properties of Binderless Insulating Boards Made from Canary Island Date Palm and Cork Particles

Agglomerated cork is a natural cork that has gone through a process of crushing and pressing using heat and binders. One of its applications is thermal insulator in construction. The design of these materials is becoming an essential part of building. The raw materials currently used to make insulators consume a large amount of energy, which has created the need to increase the use of renewable and ecological resources such as plant fibers to reduce the environmental problems generated. The objective of this study was to determine the different properties of experimental particleboard panels made from cork and Canary Island date palms without using any binder at minimum energy consumption. The produced cork–palm boards (density of 850 kg/m3, reached a MOR 8.83 N/mm2, MOE 794.5 N/mm2, and IB 0.38 N/mm2) are higher values than the traditional cork particleboards with UF made from cork. The thermal conductivity values obtained 0.069 to 0.096 W/m·K are higher than cork boards with UF. Ecological boards that can be used as rigid thermal insulators in the construction industry have been achieved to improve the mechanical properties of the traditional agglomerated cork.

Analysis of Urban Thermal Environment Improved by Blue-Green Spaces on the Landsat Data: A Case Study on Tianjin

China’s urbanization is characterized by rapid speed, large scale and high energy consumption, which causes a series of ecological problems. Among these problems, urban thermal environment is particularly prominent, and the most intuitive reflection is the heat island effect. It is of great significance to optimize the urban layout to give full play to the cooling effect of blue-green spaces for improving urban thermal environment. Compared with other methods, it is more extensive and feasible. However, the current research on urban thermal environment mostly focuses on revealing the driving effects of different land use, and lacks of in-depth discussions on blue-green spaces. Tianjin is located in the northeast of the North China Plain, and has a typical warm temperate sub-humid monsoon climate. This paper takes the six districts of Tianjin City as the research area, covering Heping District, Nankai District, Hongqiao District, Hebei District, Hexi District and Hedong District, with a total area of about 181.18 square kilometers. The typical climate and urbanization characteristics of Tianjin can provide reference for cities with the same characteristics. Firstly, this paper had adopted the Landsat changing scenario of the city gained during the periods of 2004, 2011 and 2017 to formulate the land surface temperature by Mono-window Algorithm, and divided the results into seven temperature zones by standard deviation classification method. In regard to blue-green spaces, this paper had identified Landsat satellite data by Maximum Likelihood Classifier, and classified land use into three categories: blue spaces, green spaces, and non-blue and green spaces. And, next, this paper had studied the correlation between the landscape pattern of blue-green spaces and urban thermal environment by Landscape Pattern Analysis, and used Moving-window Analysis to compare the relationship between thermal environment and blue-green spaces at different spatial scales. And so the research results prove that, the high-temperature regions of Tianjin has been expanding along with the expansion and agglomeration of the urban areas and across the river space restrictions, while the low-temperature regions of the city are mainly concentrated in the blue-green spaces, during the periods of 2004, 2011 and 2017. Furthermore, in the landscape pattern level, there is a significant negative correlation between patch perimeter index of blue-green spaces and land surface temperature, and a significant positive correlation between patch perimeter area ratio index of blue-green spaces and land surface temperature. In the multi-scale spatial pattern, the correlation between the Percent of Landscape of blue spaces patches and land surface temperature is the highest in the 1500 meters × 1500 meters sample, and the Percent of Landscape of green spaces patches and land surface temperature is the highest in the 300 meters × 300 meters sample. In addition, the improvement efficiency of thermal environment in blue spaces is higher. In the end, the optimization suggestions of adjusting the layout of blue-green spaces to effectively improve the urban thermal environment problem are proposed. By optimizing the blue-green space landscape patterns at the optimal scale, increasing the blue spaces in the northern high temperature range, widening and transforming the existing waterways, constructing riverside greenways and other strategies to effectively deal with the thermal environmental problems, improving the ecology and livability of the city. It is hoped to provide new ideas and references for the construction of ecological and livable city under the background of rapid urbanization. In the research process, due to the limitation of data sources, calculation methods and other factors, the relevant conclusion is still limited at the spatial scale. In the future research, the thermal environment and the pattern of blue-green spatial landscape at the fine scale will be studied.

Enterprise green entrepreneurship orientation: research review and outlook

With the rapid development of economy, excessive resource consumption, environmental pollution, ecological civilization construction has become a global common theme, green development concept become the topic of attaches great importance to today's society, enterprises also realized that the enterprise development not at the expense of the environment, from the traditional economy to green economy is imperative. The academic and practical circles began to pay attention to the potential of green entrepreneurship in environmental protection, and green entrepreneurship, as the premise of green entrepreneurship, is the active strategic tendency of enterprises to deal with environmental problems, emphasizing the identification and grasp of eco-friendly opportunities, which reflects the active attitude of enterprises towards environmental issues. Although existing research has made some progress, but few systematic summary to clarify the development of green entrepreneurial orientation, based on this, this study from the connotation, dimension, driving factors and influencing factors combed the green entrepreneurship oriented research progress, and put forward the future outlook, in order to provide support for subsequent green entrepreneurship research.

Isolation of biocrust cyanobacteria and evaluation of Cu, Pb, and Zn immobilisation potential for soil restoration and sustainable agriculture

Soil contamination by heavy metals represents an important environmental and public health problem of global concern. Biocrust-forming cyanobacteria offer promise for heavy metal immobilisation in contaminated soils due to their unique characteristics, including their ability to grow in contaminated soils and produce exopolysaccharides (EPS). However, limited research has analysed the representativeness of cyanobacteria in metal-contaminated soils. Additionally, there is a lack of studies examining how cyanobacteria adaptation to specific environments can impact their metal-binding capacity. To address this research gap, we conducted a study analysing the bacterial communities of cyanobacteria-dominated biocrusts in a contaminated area from South Sardinia (Italy). Additionally, by using two distinct approaches, we isolated three Nostoc commune strains from cyanobacteria-dominated biocrust and we also evaluated their potential to immobilise heavy metals. The first isolation method involved acclimatizing biocrust samples in liquid medium while, in the second method, biocrust samples were directly seeded onto agar plates. The microbial community analysis revealed Cyanobacteria, Bacteroidota, Proteobacteria, and Actinobacteria as the predominant groups, with cyanobacteria representing between 13.3 % and 26.0 % of the total community. Despite belonging to the same species, these strains exhibited different growth rates (1.1–2.2 g L−1 of biomass) and capacities for EPS production (400–1786 mg L−1). The three strains demonstrated a notable ability for metal immobilisation, removing up to 88.9 % of Cu, 86.2 % of Pb, and 45.3 % of Zn from liquid medium. Cyanobacteria EPS production showed a strong correlation with the removal of Cu, indicating its role in facilitating metal immobilisation. Furthermore, differences in Pb immobilisation (40–86.2 %) suggest possible environmental adaptation mechanisms of the strains. This study highlights the promising application of N. commune strains for metal immobilisation in soils, offering a potential bioremediation tool to combat the adverse effects of soil contamination and promote environmental sustainability.

Heavy metal tolerance and detoxification mechanism mediated by heavy metal resistance genes in compost habitat.

Heavy metal pollution from compost is one of the most concerned environmental problems, which poses a threat to the ecosystem and human health. This study aims to reveal the heavy metal tolerance and detoxification mechanism mediated by heavy metal resistance genes (HMRGs) in compost habitat through metagenomics combined with chemical speciation analysis of heavy metals. The results showed that there were 37 HMRGs corresponding to 7 common heavy metal(loid)s in composting, and they had the ability to transform heavy metals into stable or low-toxic speciation by regulating enzyme transport, redox, methylation, etc. This study summarized the heavy metal metabolism pathway mediated by HMRGs, providing a new perspective for understanding the transformation of heavy metals in the composting process.

MXenes as Electrocatalysts for Energy Conversion Applications: Advances and Prospects

Hydrogen as a potential future energy source provides a number of benefits in terms of sustainability, high energy density, and zero emissions. The production of hydrogen via water splitting is regarded as the cleanest and sustainable process. In contrast, fossil fuel combustion causes significant environmental problems through the production and release of secondary gases such as NOx, SO2, and CO2. It is vital to focus on reducing these harmful gases. CO2, a major pollutant produced by the combustion of fossil fuels and various human activities, plays a central role in the greenhouse effect and contributes to global warming. It is therefore imperative to actively eliminate and mitigate CO2 levels to preserve the global environment. MXenes and MXene‐based catalysts exhibit both outstanding hydrogen evolution reaction (HER) performance and CO2 reduction. In this review, recent progress is systematically examined and discussed in the preparation and utilization of MXenes as catalysts for HER and carbon dioxide reduction reaction (CO2RR). The discussion begins with a concise overview of the fabrication and characteristics of MXenes, followed by a comprehensive exploration of their efficacy as catalysts for HER and CO2RR.