Different Types Of Pollutants Research Articles

Modeling and analysis of the effects of barrier height on automobiles emission dispersion

In this paper, a mathematical model has been developed that describes the characteristics of fluid flow and dispersion of pollutants in a certain quarter of Almaty city, Kazakhstan. The influence of traffic tidal flow was investigated based on the results of passing vehicles measurements as a source of pollution by the CFD method and on the spatial distribution of pollutants for different types of pollution. To validate the numerical algorithm and mathematical model, a test problem was performed. The RNG k-ε turbulence model was used as a turbulent model. The obtained data were compared with the measured and calculated values. After validation of the mathematical model, the main problem was characterized: the pollutant emissions process between houses using different types of pollution sources and the presence of different heights of barriers. The calculated data were compared with the obtained calculated values. In the course of various studies, it has been found that, despite different types of pollutants, the presence of barriers along the road reduces the concentration of harmful substances in the pedestrian zone air. And also the optimal height of this barrier along the road was chosen for maximum protection of the pedestrian part from harmful pollutants. And it was found that when using a barrier with a height of 3 m, the concentration value drops more than two times, as opposed to without a barrier, and a further increase in height is not economically profitable and does not give the desired results.

Comparison of adsorption behaviors and mechanisms of methylene blue, Cd2+, and phenanthrene by modified biochars derived from pomelo peel.

Although biochar (BC) has been widely used to adsorb pollutants in environment due to its natural and green characteristics, the structural defects of BC limit the ability to remove various environmental pollutants in aqueous solution. In this study, oxidized biochar (OBC) and sulfhydryl biochar (SBC) derived from pomelo peel (PP) were prepared through an oxidation and esterification reaction. BC and modified BC were used for the removal of methylene blue (MB), Cd2+, and phenanthrene (PHE) in aqueous solution. The adsorption behavior and efficiency toward different types of pollutants were studied by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Raman, X-ray photoelectron spectroscopy (XPS), kinetics, and isotherm model fitting. The results showed that the change of pH had great effect on MB and Cd2+ adsorption, but not on PHE. SBC not only possessed the newly formed sp2-hybridized domains with easy access to aromatic pollutants but also had multiple functional groups (-COOH, -OH, -SH, -NH2) that provided adsorption sites for positively charged pollutants. SBC was more flexible and efficient in purifying pollutants compared to BC and OBC, with the saturated adsorption capacities of MB (209.16 mg/g), Cd2+ (786.19 mg/g), and PHE (521.58 mg/g). Moreover, the adsorption kinetic and isotherms fitting showed that the adsorption mechanisms were closely related to the structure of biochar and the properties of pollutants, including π-π interaction, surface charge, electrostatic interaction, surface functional groups, and Van der Waals force. In addition, the analysis of structure-function relationship demonstrated the enhanced hydrophilicity and the easy exposure of the binding sites on OBC and SBC. Hence, it was significantly effective to regulate microstructure and interfacial properties to promote its adsorption behaviors of biochar.

Environmental regulation, local legislation and pollution control in China

Abstract This paper conducts a novel empirical analysis of the effect of environmental regulation on local pollution emissions by taking 84 cases of local legislation among 31 provinces in China during 1990–2009. We combine the matching methodology and difference-in-difference method to estimate the causal effect of provincial environmental legislation. Our estimation uncovers that there is no significant pollution abatement effect, however, environmental legislation helps to decrease local pollution emission only for those provinces that have stricter enforcement. Such results remain robust while considering the time lag effect, different types of pollutants, choice of different comparison groups and using of synthetic control method. Generally, our study shows the importance of the enforcement for environmental legislation in China.

Effect of different types of anthropogenic pollution on the bacterial community of urban rivers

The health of urban rivers is threatened by multiple anthropogenic stressors. Bacterial communities in rivers can quickly respond to different types of polluted environments, making them useful for water quality assessments and predictive insights. However, research on river bacterial communities has largely ignored interactions between these communities. Here, 16S rRNA amplicon sequencing analysis is used to comprehensively analyze the bacterial communities in the water and sediments in different types of anthropogenically impacted urban river. The results show that distinct differences occur in the bacterial communities in the river sediment and water with different pollution types. The changes in the bacterial communities in sediments were more pronounced than those in the water. A modular analysis further showed that the microbial co-occurrence network under different types of pollution had a nonrandom modular structure, and this structure was mainly driven by classification correlation and bacterial function. Genes identified for nitrogen cycling in all the river water and sediment samples included major functional genes for nitrogen fixation, assimilatory nitrogen reduction, nitrification, denitrification, and ammonification. Carbon degradation genes were mainly observed in the carbon cycle. Taken together, the above findings provide further insights into microbial communities in urban river ecosystems under anthropogenic contamination. PRACTITIONER POINTS: The physical and chemical indicators of the four types of pollution drive bacterial community structure. Bacterial community has C, N, P metabolic genes indicating its ecological effect. River bacteria were connected more frequently in the same or similar type of pollution in the co-occurrence network. Microbe-environment correlations and microbe-microbe interactions were combined to determine crucial indicators.

Research on water quality and pollution characteristics of a typical coastal plain river network

Pinghu City is a typical coastal city in Zhejiang Province. It has confronted many problems such as low velocity of the river network and poor quality of the water ecological environment. Water pollution has seriously affected the local social and economic development as well as the residential environment. In this study, the plain river network of Pinghu City is selected as an example to analyze the amount of various pollutants. Different types of pollutants are calculated based on the statistic data. The pollution characteristics of the coastal plain river network in Pinghu City is then collected and analyzed. This study will provide further treatment solutions for water pollution in cities with typical coastal plain river network in Zhejiang Province.

Identification and Quantification of Polycyclic Aromatic Hydrocarbons in Polyhydroxyalkanoates Produced from Mixed Microbial Cultures and Municipal Organic Wastes at Pilot Scale.

Polyhydroxyalkanoates (PHAs) are well-known biodegradable plastics produced by various bacterial strains, whose major drawback is constituted by the high cost of their synthesis. Producing PHAs from mixed microbial cultures and employing organic wastes as a carbon source allows us to both reduce cost and valorize available renewable resources, such as food waste and sewage sludge. However, different types of pollutants, originally contained in organic matrices, could persist into the final product, thus compromising their safety. In this work, the exploitation of municipal wastes for PHA production is evaluated from the environmental and health safety aspect by determining the presence of polycyclic aromatic hydrocarbons (PAHs) in both commercial and waste-based PHA samples. Quantification of PAHs by gas chromatography-mass spectrometry on 24 PHA samples obtained in different conditions showed very low contamination levels, in the range of ppb to a few ppm. Moreover, the contaminant content seems to be dependent on the type of PHA stabilization and extraction, but independent from the type of feedstock. Commercial PHA derived from crops, selected for comparison, showed PAH content comparable to that detected in PHAs derived from organic fraction of municipal solid waste. Although there is no specific regulation on PAH maximum levels in PHAs, detected concentrations were consistently lower than threshold limit values set by regulation and guidelines for similar materials and/or applications. This suggests that the use of organic waste as substrate for PHA production is safe for both the human health and the environment.

Экологический ракурс пандемии COVID-19: новый шанс для “зеленой” экономики

The article investigates the changes in environment that occurred in response to economic processes during the COVID‑19 pandemic (2019–2021), and related transformation of socio-political attitudes towards Green Policy and Green Economy. From the environmentalistic point of view, the pandemic played a twofold role. On the one part, it allowed the nature to “take a break” from an excessive anthropogenic pressure on the atmosphere and hydrosphere, and once again mobilized the humanity to reconsider the principles of interaction with the environment. On the other part, different types of pollution (daily and medical waste, plastic) increased dramatically; funding of international and national environmental programs was cut due to the economic recession worldwide. Nevertheless, the multidimensional crisis caused by the pandemic gave a new chance to the Green Economy. The most influential states of the world (the EU countries, USA, China and Russia) actively implement the Green Economy instruments at the state level. This process incorporates all economy sectors: finances, energy, industry, transport, agriculture and other. The European Union which had taken this path before the pandemic started is in an advanced position. At the same time, the foundations of the future environment-oriented economic policy are already enshrined in official documents (strategies, action plans, legislative acts, etc.) adopted by the leading nations thus far. Noteworthy is that the COVID‑19 crisis has updated the green political and economic agenda globally, regardless of differences between the states, which verifies the importance and necessity of agreeing a conceptually new approach to interaction with the environment in the short and long term.

Recent progress on electrochemical sensing strategies as comprehensive point-care method

The most important part of all kinds of life on Earth is water. The demand for drinking water is increasing due to water pollution and other natural causes. Different types of pollutants in water (metal ions, organic compounds, inorganic salts, pathogens, insecticides, pharmaceuticals) infect the human body and cause many diseases, and some pollutants can be carcinogenic and even fatal. Therefore, there is the need of the day to detect and monitor pollutants. However, many conventional methods are being used, but not all of them effective for sensing multiple harmful components in water. Recently, electrochemical sensing has evolved as potential tools to recognize heavy metal ions, organic chemicals, pesticides, and pathogens into water. The current review covers recent progress in electrochemical sensing of water pollutants, which is helpful for human health protection.

Iron sulfide nanoparticles prepared using date seed extract: Green synthesis, characterization and potential application for removal of ciprofloxacin and chromium

Iron sulfide (FeS) nanoparticles have emerged as promising materials for a wide range of applications. Despite the growing interest, only conventional wet chemical synthesis approaches for FeS are prevalent, while alternate nontoxic green synthesis methods have not yet been explored. In this study, we demonstrate a novel green approach for the reduction of iron sulfate salt to iron sulfide nanoparticles using aqueous extracts from date tree (Phoenix dactylifera) seeds (ds-FeS nanoparticles). Detailed characterization techniques revealed the formation of spherical FeS nanoparticles with a mean nominal size of 68 nm, while spectroscopy studies confirmed the role of date seed phytochemicals in the synthesis and capping of ds-FeS. We also demonstrate the potential of using ds-FeS for water treatment by efficiently removing two different types of pollutants- ciprofloxacin (pharmaceutical) and hexavalent chromium (heavy metal). Results from this study maybe useful towards further exploration and optimization of eco-friendly synthesis routes for nanoscale iron sulfides.

Carrier lifetime regulation strategy to improve the sewage purification capacity of superhydrophobic silver phosphate fabric

Sewage contains a variety of components including oil slick and water-soluble pollutants. How to remove different types of pollutants at the same time is a challenge. In this paper, superhydrophobic fabric (SH fabric) was prepared by the combination of silver phosphate photocatalyst with fabric substrate. Surface oil slick and rhodamine B contaminants can be removed simultaneously by SH fabric. The degradation efficiency after three cycles is still maintained above 90% under outdoor light source conditions. In order to improve the degradation efficiency of silver phosphate photocatalyst, ethanol/water mixed solvent was used. And the reasons for the improvement of catalyst performance were studied systematically. It is found that the charge transfer resistance of the silver phosphate catalyst prepared by addition of ethanol (S-3) decreases, while the carrier concentration and lifetime increase. The VB and CB of silver phosphate with the best degradation performance (S-3) are 2.425 eV and 0.135 eV, respectively. It is hoped that this SH fabric could provide a new solution to the improvement of catalyst performance and comprehensive treatment of sewage.

The prospective utilization of Luffa fibres as a lignocellulosic bio-material for environmental remediation of aqueous media: A review

Luffa is an excellent biomaterial that has gained much attention since it is low-cost, available, environmentally-friendly, non-toxic, porous and efficient for the removal of environmental pollutants, including dyes, pharmaceuticals, and heavy metals. This review provides an insight into the key factors, including contact time, pH, pollutant concentration, adsorbent dosage, and temperature that may affect the Luffa performance in removing contaminants. Thereafter, Luffa and its composites were characterized by SEM, FTIR, BET, XRD, EDAX, and TGA. This paper reviews the current state of research on the use of raw Luffa and modified Luffa, and compare the results with other investigations. It was found that Luffa – based composites might be great potential candidates for water decontamination. Adsorption equilibrium and kinetics were also studied and it was found that Langmuir/Freundlich and Pseudo-second order models were in great agreement for many studies. Results confirmed that Luffa and its composites possess good applicability in removing different types of pollutants from aqueous solutions.

Evaluation of Dust Deposition on Parabolic Trough Collectors in the Visible and Infrared Spectrum.

Solar energy is mostly harnessed in arid areas where a high concentration of atmospheric dust represents a major environmental degradation factor. Gravitationally settled particles and other solid particles on the surface of the photovoltaic panels or thermal collectors greatly reduce the absorbed solar energy. Therefore, frequent cleaning schedules are required, consuming high quantities of water in regions where water precipitation is rare. The efficiency of this cleaning maintenance is greatly improved when methods to estimate the degree of cleanness are introduced. This work focuses on the need for better detecting the degradation created by dust deposition, considering experimental data based on different air pollutants, and analyzing the resulting thermal and visible signatures under different operating environments. Experiments are performed using six different types of pollutants applied to the surface of parabolic trough collectors while varying the pollutant density. The resulting reflectivity in the visible and infrared spectrum is calculated and compared. Results indicate that the pollutants can be distinguished, although the reflectivity greatly depends on the combination of the particle size of the pollutant and the applied amount, with greater impact from pollutants with small particles.

Applications of Green Synthesized Nanomaterials in Water Remediation.

Water is the most important component on the earth for living organisms. With industrial development, population increase and climate change, water pollution becomes a critical issue around the world. Its contamination with different types of pollutants created naturally or due to anthropogenic activities has become the most concerned global environmental issue. These contaminations destroy the quality of water and become harmful to living organisms. A number of physical, chemical and biological techniques have been used for the purification of water, but they suffer in one or the other respect. The development of nanomaterials and nanotechnology has provided a better path for the purification of water. Compared to conventional methods using activated carbon, nanomaterials offer a better and economical approach for water remediation. Different types of nanomaterials acting as nanocatalysts, nanosorbents, nanostructured catalytic membranes, bioactive nanoparticles, nanomembranes and nanoparticles provide an alternative and efficient methodology in solving water pollution problems. However, the major issue with nanomaterials synthesized in a conventional way is their toxicity. In recent days, a considerable amount of research is being carried out on the synthesis of nanomaterials using green routes. Nanomaterials synthesized by using the green method are now being used in different technologies, including water remediation. The remediation of water by using nanomaterials synthesized by the green method has been reviewed and discussed in this paper.

Photodegradation of Cationic and Anioic Dyes by pH-Dependent Dispersion of Amphoteric g-C₃N₄ Nanosheets.

g-C₃N₄ nanosheets (NSs) were prepared via H₂SO₄ exfoliation from the bulky g-C₃N₄ and the photocatalytic (PC) activities were investigated comprehensively using Rodamine B (RhB) and Chromotrope 2R (Ch2R) as candidate pollutants. The results showed that the pH value have important functions in the improvement of photodegradation performance of C₃N₄ NSs. RhB as cationic dye could be photodegraded more efficiently under acidic conditions while Ch2R as anionic dye was degraded easily in pH ≥ 11 solution. In particular, the Ch2R could be degraded completely within only 30 min in pH = 11 solution. It might be because the amphoteric C₃N₄ NSs surface with carboxyl and amino groups possessed negative and positive charges in alkaline and acidic conditions, respectively. These results presumably provided a new idea to enhance the pH-dependent photodegradation activity and degrade different types of pollutants selectively by adjusting the pH of amphoteric nanocatalyts.

Reduced output of photovoltaic modules due to different types of dust particles

Dust accumulation is one of the main contributing factors for the power loss of photovoltaic (PV) modules. Dust consists of small particles that float throughout the atmosphere. Types of dust are often overlooked. This study aimed to investigate the effect of different types of dust particles on PV performance. The dust particles investigated include carbon (C), iron oxide, manganese dioxide, calcium oxide and natural dust. The first part of this study focused on the effects of the different types of pollutants on the external load. The second part examined the PV performance at variable load. The results show that the carbon to have appears the worst reduction impact on PV performance with about 99.76% in the range of density of mass from 0 to 20.27 g/m2 and 99.9% in the range of density of mass from 0 to 41 g/m2 in the case of fixed load and variable load respectively. The lower results reported by natural dust about with 98.92% in the range of density of mass from 0 to 164.38 g/m2, 80% in the range of density of mass 0–123.28 g/m2 for fixed and variable load respectively.

Does Environmental Innovation Improve Environmental Productivity?—An Empirical Study Based on the Spatial Panel Data Model of Chinese Urban Agglomerations

Environmental productivity comprehensively measures economic growth and environmental quality. Environmental innovation is considered to be the key to solving economic and environmental problems. Therefore, discussing the impact of environmental innovation on environmental productivity will reveal its economic and environmental effects. This paper measures environmental productivity by value added per unit of pollution emissions (four types of emissions are used) using panel data of 10 Chinese urban agglomerations from 2003 to 2016 to analyze the spatial correlation of environmental productivity, and constructs a spatial panel data model to empirically test the impact of environmental innovation on environmental productivity. It was found that environmental productivity measured by value added per unit of carbon dioxide emissions (gross domestic product (GDP)/CO2) had a significant positive spatial spillover effect, and measured by value added per unit of sulfur dioxide emissions (GDP/SO2), smoke (dust) emissions (GDP/SDE), and industrial sewage emissions (GDP/IS) had a significant negative spatial spillover effect. Environmental innovation has a significant negative inhibitory effect on environmental productivity measured by GDP/SDE and GDP/IS, but no obvious effect measured by GDP/CO2 and GDP/SO2. Control variables such as economic development level, industrial agglomeration, foreign direct investment, and endowment structure factor also show significant differences in environmental productivity measured by value added per unit of pollution emissions. In addition, there are significant differences in direct effects of explanatory variables on environmental productivity of local regions and indirect effects on neighboring regions. These differences are also related to the types of pollution emissions. Therefore, policymakers should set different policies for different types of pollution and encourage different types of environmental innovation, so as to achieve reduced pollution emissions and improved environmental productivity.

Waste Water Treatment by Using Moving Bed Bio Film Reactors

Waste water treatment is essential to re use of used water. In this paper we discuss about the waste water treatment , process and various techniques used for the treatment process. Waste water treatment is also important factor for safety of the environment conditions. To make the environment free from hazardous conditions and to make the sustainable environment. It is also controls different types of pollutions in the water. It is eco friendly in nature. Waste water engineering is the branch of Environmental engineering. which deals with occurance, distribution and treatment of waste water and recycle use of waste water. It also used for study of design construction of structures related to supply of potable water towards public. To prevent water borne diseases from the water. It is also used for disposal of waste water by selecting suitable locations . the study of waste water is also important to understand the various types of pollutions in the soil. This knowledge helps to better usage of water and disposal of the water

Progress of using zeolite materials in soil remediationengineering

<p indent="0mm">Soil contamination has become a global environmental crisis due to the development of the industry. Exploring cost-effective and long-term active soil remediation materials is the key to tackle the soil contamination problem. Based on excellent absorption and cation exchange capacity (CEC), zeolite molecular sieve materials have been widely used in soil remediation. Herein, we summarize the available works in the literature on conventional zeolite materials which have been applied in soil remediation. Especially, focusing on composition and structure features of zeolite materials, we elaborate on their structure-activity relationship down to details. Besides, the microscopic interaction between zeolites and soil contaminants have elucidated. The research process of zeolite used in soil remediation has been reviewed. As discussed in this review, for the conventional zeolite materials used for soil remediation can be classified into pure zeolite materials and zeolite-based composite materials. Pure zeolite materials can be divided into natural zeolites and synthetic zeolites. Natural zeolites are cheap but with multiple elements inside the structure and composition, which is of low purity, and small pore volumes. Ion exchange, acid/alkali washing, and heat treatment are standard methods that have been used to improve the sorption capacity of natural zeolites. Compared to natural zeolites, synthetic zeolites are with tunable compositions and frameworks with high purity. But the cost for synthetic zeolites is higher, which hinders their large-scale application. In recent years, zeolite-based composite materials have been frequently employed as a composite material mixed with other kinds of materials, including nanoscale zero-valent iron or biochar, or humic acid, etc., for soil remediation. The obtained composite materials can be nanoscale zero-valent iron/zeolite composite materials (Z-nZVI), humic acids/zeolite composite materials (HZ), and biochar/zeolite composite materials (BZ). Usually, the soil remediation effect of zeolite-based composite materials is better than pure zeolite materials due to the synergy between the components. Targeting different types of pollutants in the soil requires the dedicated zeolite materials for the treatment, and the microscopic interaction mechanism between zeolite materials and pollutants are also various. For cationic contaminants, such as heavy metal ions, zeolite with low Si/Al ratio and large pore size are effective amendments, because the soil remediation effect directly correlated to the CEC in the used materials. As most of the zeolites have a net negative structural charge, which typically results in little or no affinity for anionic species. Therefore, pure zeolite materials are rarely used for anionic pollutants remediation. While combining zeolite with other materials, such as nZVI, both the cationic and anionic pollutants in the soil can be effectively removed. Moreover, organic pollutants can also be removed by zeolite as the organic pollutants can be physically adsorbed within the zeolite channels through Van der Waals forces or hydrogen bonding. The adsorption capacity of zeolite materials on the organic matter is heavily dependent on the zeolites’ pore sizes and hydrophobic properties. Usually, zeolites with a high Si/Al ratio and large pore size can be used to immobilize organic pollutants more effectively. We concluded this review with some perspectives. We think that elucidating the remediation mechanism down to the atomic-scale and optimizing the green chemistry synthesis process for zeolites are two urgent approaches that need to be considered seriously soon.

Does air pollution aggravate income inequality in China? An empirical analysis based on the view of health

Given the rapid development of the Chinese economy, especially its accelerated urbanization, air pollution and income inequality, as two of the most important global issues, have also become hot topics in China. However, limited attention has been devoted to understanding their joint evolution in the literature. In this study, we thus investigate the relationship between them using a multi-level nested data model, which enables us to estimate the long-run distribution effect of air pollution on individuals of different socioeconomic statuses, based on China’s city-level PM2.5 emissions and individual-level income. We further examine the mechanisms behind the evolution using a 3SLS model. The estimation results reveal that the increase in air pollution concentration has short-term positive production effects and long-term negative impacts on individual income, and will exacerbate the income inequality across socioeconomic statuses. Individuals of lower socioeconomic status have disadvantages in achieving efficient avoiding knowledge and measures. The results of 3SLS model confirm the existence of the health channel through which air pollution exerts influence on income inequality. These results provide a roadmap for policymakers. First, a comprehensive assessment of the health burden distribution from air pollution on individuals of different socioeconomic statuses should be considered for environmental policymaking. Second, the regional disparities and differences among income groups should also be considered during this process. Third, equal access to basic public services should be the primary target of environmental regulations. Moreover, compensation and assistance for the health issues caused by environmental pollution could be an important supplement to these regulations. Future study could do further analysis of the specific level of health burden due to different types of pollutants and their relationship with income inequality.

Effect of co-application of wastewater and freshwater on the physiological properties and trace element content in Raphanus sativus: soil contamination and human health.

Nowadays, the use of wastewater for crop irrigation is increasing at global scale mainly due to freshwater scarcity and economic benefits. However, the presence of different types of pollutants including the trace elements (TEs) poses a serious threat to environmental and human health. This pot study evaluated the effect of alone and mixed irrigation water [wastewater (WW) with canal water (CW) and tube-well water (TW)] on TEs build-up in the soil, their soil-plant transfer and allied health hazards in District Vehari. The WW samples were mainly contaminated with Cd (0.03mg/L), Cr (1.45mg/L), Cu (0.35mg/L) and Ni (0.40mg/L). The CW contained high levels of Cr and Fe, while TW was contaminated with Pb and Cr. In soil, the concentrations of Cd, Fe and Mn exceeded their respective limit values for all the treatments. Among all the treatments, TEs concentration was found highest in WW-3 irrigated soil. Application of all the treatments resulted in TEs (Cu, 60.1mg/kg; Cd, 8.2mg/kg; Ni, 39.9mg/kg; Fe, 4411mg/kg; Zn, 111.3mg/kg and Pb, 44.5mg/kg) accumulation mainly in the edible parts of Raphanus sativus. Compared to other treatments, TW and TW + CW irrigated plants accumulated higher levels of TEs. Results showed linear trends among TEs accumulation and alterations in physiological attributes of R. sativus. High TEs accumulation in TW irrigated treatments (TW + WW-1 and TW + CW) caused maximum H2O2 production, lipid peroxidation and decline in plant pigments. Risk assessment parameters showed both carcinogenic and non-carcinogenic risks for all the irrigation treatments due to high TEs contents in edible tissues. It is concluded that alone or combined application of WW, TW and CW is not fit for vegetable irrigation, in the studied area, due to high TEs contents.