Environmental pollution is currently one of the major problems that are threatening biodiversity, ecosystems, and human health around the world. Natural rubber, which is one of the most significant polymers due to its variety of uses, has now become a serious environmental concern. Rubber waste management poses one of the greatest problems because it is extremely resilient and persists in the environment despite several mitigation efforts. Biodegradation is an eco-friendly alternative to conventional disposal methods and has gained tremendous interest in recent years. Several studies on rubber biodegradation utilizing fungi and bacteria have been reported. However, except for a few studies on technical applications, the majority of research on these microbes has focused on the fundamentals of rubber biodegradation. The challenge with biodegradation as a potential solution for rubber waste management is that we have limited mechanistic insight into rubber biodegradation, and the complicated composition of rubber products inhibits cell growth and activity of microbes. Thus it becomes important to fully comprehend the mechanism of rubber biodegradation and continue the search for new microbial strains so that the acquired knowledge can be utilized to develop a biodegradation process suitable for scale-up. In this short review, rubber degradation using fungi and bacteria is highlighted.

Fiber-reinforced technology is an important method to improve the stability and durability of growing basis material. To evaluate the factors affecting the interfacial strength properties of polypropylene fiber reinforced vegetation concrete, single polypropylene fiber drawing tests were conducted by using a modified apparatus. The mechanical interaction behavior between vegetation concrete and polypropylene fiber was discussed by using a polarizing microscope. The results indicate that the drawing curves between polypropylene fiber and vegetation concrete show a typical multi-peak characteristic. And the interfacial shear strength is the minimum at the optimum water content (20%) in the 1d sample. It should be noted that both interfacial peak strength (IPS) and interfacial residual strength (IRS) increase with the increase of dry density and curing time for vegetation concrete. Then through multiple linear regression analysis, the empirical formula of critical fiber length in reinforced vegetation concrete is obtained, which can improve the engineering durability of vegetation concrete in harsh conditions.

In recent years, the water environment management of the Wenyu River has yielded positive outcomes. In comparison to earlier, the general water quality has substantially improved. However, some areas’ water quality has not improved as a result of the overall trend of improvement, which has implications for the surrounding areas and the entire water environment. To further explore the water environmental quality of specific river sections, this paper adopts the five monitoring sections of Shahe Gate, Mafang, Lutuan Gate, Xinbao Gate, and the additional sewage outlet in 2019, and the three main water quality indicators of COD, DO, and NH3-N. The water quality of the Wenyu River was evaluated using the comprehensive water quality identification index method, and the characteristics of its temporal and spatial changes were studied using correlation analysis and spatial clustering. The results have shown that the Wenyu River is generally Grade V water during the flood season, and is inferior to Grade V water during the non-flood season. All indicators have a regular time and space distribution and are highly influenced by environmental and human factors. Overall, the water quality of the Wenyu River may essentially reach the water environment function zoning target value. Improvements to the river portions below the Xinbao sluice, as well as the use of rainwater resources, must be prioritized.

This study focused on the ion release and microstructure of slag during its degradation following erosion by different pH solutions. It focused on controlling factors such as slag particle size range, pH value of the solution, and soaking time. The surface microstructure and particle size distribution of slag with the particle size of 0.075–5.0 mm, the mineral composition of suspended pollutants larger than 0.45 μm, and the phenomenon of nano-scale ion release were examined. When slag was soaked in solutions with different pH values for 30 days, the pH value of leachate tended to be neutral, the release amount of Ca, Mg, Fe, and Cd ions increased and the release rate gradually decreased. The dissolution process of slag in the alkaline solution was slower than that in acid, but suspension and gels formed more easily in an alkaline environment. Nitric acid accelerated the chemical reaction of akermanite, gehlenite, and hawleyite, and released Ca, Mg, and Cd ions. There were clear damage cracks and various irregular pores on the slag surface. Under the attack of alkali solution, the weight of akermanite in slag increased, the Mg ion content in solution decreased, and the suspended solids of calcite and portlandite increased. At pH 12, unlike at pH 3, there were no large surface cracks in the slag and the interface damage was small. Compared with pH 7, there were more irregular substances, such as flakes and spheres. The particle size of slag was mainly 0.1–0.5 mm, the content before and after leaching was 52.80%–55.87% and 55.00%–58.27%, and the slag was in a poor grading state. The findings of this study act as an important reference for understanding the influence of slag leaching on water and soil pollution.

Heavy metals, especially Pb (lead), are generally toxic to living things. Pb can contaminate organisms in the water through the food chain. The purpose of this study is to enhance water quality by using Salvinia molesta to phytoremediate Pb-polluted water. This study aims to evaluate the ability of S. molesta as a Pb phytoremediator. We evaluated total protein, free amino acids produced by the plant, and plant growth (dry biomass). S. molesta was grown in a hydroponic system exposed to Pb at dosages of 0, 5, 10, and 15 ppm for 7 and 14 days. Pb level was analyzed using Atomic Absorption Spectrophotometer and amino acids were analyzed using High-Pressure Liquid Chromatography. Data were statistically analyzed using analysis of variance (ANOVA) followed by Tukey’s test (α < 0.05). Results showed a significant change in Pb content in the roots and leaves of Pb-exposed S. molesta Mitch compared to control. In Pb-exposed plants, total protein and amino acids, especially cysteine, were lowered. S. molesta could be used as a Pb phytoremediator due to its high potential to survive Pb exposure and its ability to absorb Pb.

In today’s context, there is a tremendous potential for the design of smart nanomaterials of carbon origin for multi-dimensional applications. The role-play of precursor is significant in the design of nanometric carbon materials apart from other experimental parameters. Correlation of the synthetic methodology, the microstructure of the product helps to tune and widen the applications aspect. The present study aimed to tune the simple ketose (reducing monosaccharide) of fructose to functionalize (with O, N, and S atoms) carbon layers, microspheres of carbon, to optimize the experimental conditions, and to establish the mechanism involved in the process. The study further explored the catalytic ability of the carbon samples in the degradation of thiazine and xanthene-based textile dyes and the sensing of heavy metal ions of chromium and copper. A simple hydrothermal process, fructose as a precursor, alkaline pH, and appropriate calcination temperature provided micro and nanostructures of carbon viz. carbon microspheres (CMs), graphene oxide (GO), sulfur doped graphene oxide (S-GO), and nitrogen-doped reduced graphene oxide (N-rGO). In this study a simple mechanism for the conversion process is suggested. Further, the results of the preliminary screening study on the catalytic ability of the sulfur and nitrogen-doped graphene samples in the presence of UV and Visible light upon the degradation of methylene blue (MB), methyl orange (MO), Rhodamine-B (Rh-B) dyes were satisfactory. The adsorbent and the ion exchange capacity of the carbon microspheres were found to be excellent. The results of the study will contribute positively to the treatment and management of industrial wastewater.

This research aims to evaluate the concentration of radon gas and the risks involved as a result of exposure to it. The nuclear track detector CR-39 was used to measure radon gas in the buildings of Al-Qadisiyah University’s College of Education. For a month, 11 buildings in the college of Education at Al-Qadisiyah University were chosen to measure the radon concentration, with CR-39 reagent placed inside the sponge by two detectors for each building. The highest value of radon concentration was recorded in the CH1 model (270.5±32.9 Bq.m-3), at the building of the Department of Chemistry, and the lowest value was recorded in the Li1 model (96.9±27.7 Bq.m-3), which is the college library building with a concentration rate equal to (168). It is below the acceptable and recommended limit by the International Committee for Radiation Protection (200-300 Bq.m-3).

The current rapid urbanization, industrialization, and expansion of urban construction patterns have resulted in a large number of residual plaques in the urban area, including both the original plaques that are extremely fragmented and the new plaques that are metabolized by urban production, especially natural habitat patches are more pronounced. Ecological restoration of residual plaques plays an important role in maintaining biodiversity, protecting native species, providing ecological services, revitalizing land resources, inheriting regional characteristics, shaping urban image, and improving the ecological environment. Therefore, research on the subject is necessary and urgent. The topic is based on the ecological survey of urban residual patches and the study of the characteristic attributes of current urbanization, defining the connotation, extension, type, characteristics, and influencing factors of urban residual patches, and analyzing the process of fragmentation of residual plaques in cities and their artificial interference relationship. From the macro, meso, and micro scales, from the top level of ecological planning, the whole process of life cycle management, and the moderately disturbed bottom layer of ecological engineering nodes, three levels are restored, theoretical integration guidance and technical restoration. Based on the three dimensions of the continuous symbiosis of nature, cost control of the economy, and public participation of the society, repair and activate the remaining plaques of the city to provide technical support for the construction and sustainable development of urban ecological civilization.

The wind velocity reduces by encountering vegetation; thus, a shelter zone is generated at downstream of vegetation. Hence, planting vegetation, mainly shrubs, has widely been used to control sand transportation. However, plant shrubs in a large area of the desert are practically unsustainable and uneconomical. In this study, Computational Fluid Dynamic (CFD) and wind tunnel experiments were carried out to optimize the planting method of shrubs that could decrease the number of shrubs and increase wind erosion controlling efficiency in desert regions. The effects of shrub height, porosity, the number of shrub rows, and space between shrub rows on wind erosion control were studied. Based on the present study results, the downstream of shrubs was divided into three different zones: first erosion zone, sedimentation zone, and second erosion zone. Moreover, with the increase of shrub porosity, the first erosion zone’s length increased. In contrast, the sedimentation zone’s length decreased, whereas the length of the first erosion and sedimentation zones increased with shrub height. Hence, to make a better shelter zone, it is recommended to plant denser shrubs rows at the upstream and sparsely shrub rows at the far downstream.

Electronic waste or E-waste refers to the discarded electrical or electronic devices which have neared their useful life. Because of the toxicity and carcinogenicity of some compounds, the proper management and safe disposal of these electronic wastes have become serious challenges in recent years. Printed Circuit Boards (PCBs) are found almost in every other electronics these days, hence the present study focuses on bioleaching of metals from Printed Circuit Boards (PCBs) using bacterial and yeast strains (Stenotrophomonas maltophilia, Bacillus sp. and Candida tropicalis) isolated from heavily contaminated soil samples. A two-step bioleaching procedure was followed for maximum mobilization of metals. The isolated strains were able to mobilize metals from PCBs with different efficiencies depending on their ability to utilize the E-waste a carbon source when cultivated in minimal media. Bioleaching potential of isolated microbes on eight heavy metals (Cu, Ni, Mn, Pb, Fe, Cr, Zn & Co) in the sample were studied using AAS and SEM analysis before and after the two-step bioleaching process and found to be efficient. The study concludes that isolated bacterial and fungal species from the study can be further standardized with regard to the growth parameters and used on large scale to carry out the efficient recovery of metals that can help in recycling E-waste in the digital world.