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Analyses of Polycyclic Aromatic Hydrocarbons (PAHs) in the Ganga River Water in Uttar Pradesh, India
2023
Sonwani, Poonam | Bharti, Sandhya
Polycyclic aromatic hydrocarbons (PAHs) were analyzed in the Ganga River water samples collected from three cities. Jajmau (Kanpur), Dala Khera (Fatehpur), and Kara Kachar (Kaushambi) of Uttar Pradesh, India. At Jajmau (Kanpur), out of sixteen PAHs, eight were found in the Ganga river water in concentration (μg.L-1) order: acenaphthylene (3.8356) > pyrene (0.5878) > fluorene (0.5752) > anthracene (0.2806) > benzo(b)fluoranthene (0.1960) > phenanthrene (0.0526) > benzo(a)pyrene (0.0234) > naphthalene (0.006). In contrast, in Dala Khera (Fatehpur), two PAHs: anthracene (0.2806) and fluorene (0.07894), were observed. In Kara Kachar (Kaushambi), only single phenanthrene (0.04507) was detected. It was noticed that the three-ring types of PAHs occur commonly in all three sites. It is concerning because the river water sampled had PAH concentrations, namely Acy, Flu, Phe, and Pyr, that were relatively higher than those recommended (0.05 μg.L-1) by WHO (1998) in surface water. In contrast, the amounts of Nap, Ant, BbF, and Bap were recorded within the safe levels in Kanpur, while in the other two cities (Fatehpur and Kaushambi), Phe and Ant were detected lower than their permissible limit. Flu was measured as higher than its recommended value by WHO (1998). Similarly, the concentration of Acy, Ant, Pyr, BbF and BaP in river water samples at Jajmau, Kanpur were higher than their safe limits suggested by RIVM report 607711007/2012 for inland surface water while Nap, Flu, and Phe were lower than their recommended values. However, at, Dala Khera and Kara Kachar (Fatehpur and Kaushambi respectively), the concentrations of Ant, Flu and Phe were lower than their prescribed limits given by RIVM 607711007/2012.
Afficher plus [+] Moins [-]Effect of Compliance with Environmental Regulations in the Construction of Public Civil Works, Cajamarca, Peru
2023
Quinto, D. | Sanchez, D. | Milla, M. | Torres, M. | Cayatopa, B. | Jara, D. | Morales, E.
Construction activities produce considerable environmental effects and have resulted in a growing demand to implement favorable environmental practices. In this sense, this research aimed to evaluate the effect of the level of compliance with environmental regulations in public civil works in the San Ignacio, Cajamarca, Peru district. Data were obtained through direct observation and structured interviews in 7 selected construction sites. The deductive and analytical method was used. As a result, the level of compliance was obtained. Work 4 had the highest rank, and works 2 and 5 had the lowest. Currently, all the works are in a similar range of compliance. The degree of association between the level of compliance with environmental regulations and the current state of the civil works indicates a probability of 0.0190, which shows that the low level of compliance with environmental regulations in the construction of public civil works in the district of San Ignacio generates a deterioration in the quality of the environment and increases the possibility of administrative sanctions.
Afficher plus [+] Moins [-]Large Scale Cultivation and Pretreatment Optimization of Freshwater Microalgae Biomass for Bioethanol Production by Yeast Fermentation
2023
Karthikeyan, S.
The rapid depletion of the world’s fossil fuel reserves and global warming issues have promoted the search for sustainable alternative energy resources. In the present investigation, large-scale cultivation of naturally isolated freshwater microalgae Asterarcys quadricellulare strain was carried out using tertiary treated municipal wastewater as a growth medium in an open HRP pond for bioethanol production. A total of 12.091 kg of dry biomass was obtained at the end of the study. The lipid extracted carbohydrate rich spent microalgae biomass was converted to bioethanol by ethanolic fermentation. The biomass was first pre-treated with different concentrations of H2SO4 and HCL hydrolysis with different temperatures and reaction times. The biomass treated with a 2.0% concentration of H2SO4, showed maximum yields of glucose 308.38 mg.g-1 at 100°C with 180 min reaction time. The hydrolysates derived from the hydrolysis of microalgae biomass were used as a substrate for fermentation by using S. cerevisiae. The obtained bioethanol was analyzed using HPLC and the purity of ethanol was 90%.
Afficher plus [+] Moins [-]Investigation of Adsorption of Nd(III) on Boron Nitride Nanosheets in Water
2023
Fu, C. | He, Y. | Yang, C. | He, J. | Sun, L. | Du, K. | Zhang, X. | Sheng, G. | Li, L. | Wang, L. | Linghu, W.
In this paper, boron nitride materials were prepared by a two-step synthesis method, and this material’s adsorption property for neodymium ions was explored. The experimental results show that the adsorption capacity of boron nitride is closely related to pH. When the pH is 6.0, the adsorption performance of the material is the best; the kinetic data show that the adsorption equilibrium can be reached in about 150 min, and the adsorption capacity at equilibrium is 207.3 mg.g-1. In addition, the Freundlich and Langmuir models were used to fitting the thermodynamic results. It was found that the adsorption process of boron nitride on Nd(III) involved both monolayer adsorption and multi-layer adsorption. These data indicate that boron nitride has a good adsorption effect on Nd(III) in water and is a promising material for environmental remediation.
Afficher plus [+] Moins [-]Flood Mitigation and Pollution Abatement in Kaduna Metropolis Through Engineering Assessment and Analytical Hierarchy Process Design
2023
Oyebode, O. J. | Paul, F.
Pollution abatement and flood control activities require effective water resource planning, engineering assessment, sophisticated technology, and appropriate hydraulic structure designs. This paper x-rays flood mitigation and pollution abatement strategies that can be adopted in the Kaduna metropolis in Nigeria. Analytical hierarchy process of design, questionnaires, engineering assessment approach, and standard method for estimation of the runoff discharge was adopted for this research. Estimating water balance components and QSWAT Hydrological Model can be used with the QGIS interface for a greener environment. Suitable hydraulic systems were designed for long-term flood control in the River Kaduna catchment area through an analytic hierarchy Process. Statistical analysis, manning equations, and rational methods were utilized for adequate assessment and planning. The hydraulic discharge capacity of culverts, open channels, and other hydraulic structures was carefully checked. Flooding greatly impacts infrastructural development, and inadequate drainage systems contribute to it. Mitigation strategies, adequate water resource planning, and management will greatly benefit from addressing flood-related issues in the study area. This research provides information on the flood vulnerability of infrastructures and mitigation strategies that can be adopted in the study area. Viable policies and management strategies can be utilized to avert losses traceable to floods in developing and developed countries.
Afficher plus [+] Moins [-]Types and Distribution of Macroinvertebrates Stressed by Heavy Metals in Mangrove Forests
2023
Budijastuti, W. | Ambarwati, R. | Ducha, N. | Rachmadiarti, F. | Lisdiana, L. | Sahani, K.
Heavy metals can decrease the number of species in nature. This research aims to determine the relationship between the type of macroinvertebrates stressed by heavy metals in the Wonorejo Mangrove Area, Surabaya, East Java. This type of research is observational. The determination of stations was done using the purposive random sampling method. Tests for Pb and Cd content were carried out using the AAS method. Nutrient content testing was carried out using the AAS and Kjeldahl methods. Data analysis was presented descriptively, and multivariate analysis was done using Principal Component Analysis (PCA). Based on the present research, it can be concluded that there are variations in the type and distribution of macroinvertebrates stressed by heavy metals in the mangrove area of Surabaya. Station 1 is dominated by Ocypode ryderi, Station 2 by Assiminea sp., Station 3 by Scylla paramamosain, and Station 4 by Cerithidea sp. with the high presence of metals (Cd, Pb), and soil and water nutrients (Org-C, N) at Stations 1, 3, and 4. The Station 2 has only Pb. Assiminea sp. (Phylum Mollusca) can be the best candidate for metal bioindicators because it appears in all locations where soil and water have been contaminated with Pb and Cd metals without affecting their life.
Afficher plus [+] Moins [-]Review of Outdoor Air Pollution in Sri Lanka Compared to the South Asian Region
2023
Rathnayake, L.R.S.D. | Sakura, G.B. | Weerasekara, N.A.
Air pollution is a significant issue that affects almost all the countries in the world while predominating in South Asian Regional countries due to poverty, less attention, and less awareness towards the implementation and obeying of air quality guidelines in public. As a developing country, Sri Lanka stands at an optimum state of national air quality compared to other SARC because it is an island with a minor population compared to India, Pakistan, Bangladesh, etc. Maldives and Bhutan lie straightforwardly in owing mild air quality in SARC. However, SARC is far behind the world in maintaining optimistic air quality nationwide. Ambient air pollution-attributable deaths have become interim in past decades, a severe burden to the sustainable existence of SARC. A well-established systematic epidemiological, empirical studies and revisions regarding air pollution, strategic planning for mitigating air pollution, and frequent Spatio-temporal pollution monitoring nodes are necessary for Sri Lanka to achieve the sustainable goal. Other South Asian countries: India, Bangladesh, Pakistan, Afghanistan, Nepal, Bhutan, and Maldives, also should pay attention to minimizing outdoor air pollution nationwide for the betterment of future existence.
Afficher plus [+] Moins [-]Comparative Study on the Indoor Air Quality in Critical Areas of Hospitals in Malaysia
2023
Seng, Kerk Teck | Shen, Lee Chia | Ling, Ngo Sin | Chin, Sim Pei | Xin, Tan Jia | En, Tan Kai | Jama, Adnaan Ahmed | Hariri, Azian | Nasir, Nurul Fitriah
Indoor Air Quality (IAQ) is the air quality within and around buildings and structures, particularly regarding building occupants’ health and comfort. IAQ assessments were performed using an objective measurement of molecular gaseous pollutants to determine the IAQ profile in the hospital’s critical areas. It also analyses the effects on patients in different environments and the sources that result in deviations from approved criteria. This comparative study is aimed to investigate the concentration of different compounds in different critical departments in the hospital and propose solutions to the related problem as an improvement in indoor air quality. The data was compared with the standards and regulations. It was found that the TVOC level in the CCU department, specifically in the fluoroscopy room, has exceeded the allowable limit. A few suggestions have been raised to lower the exceeded value. The risks and symptoms held by the occupants in the hospital buildings if they face poor indoor air quality were discussed. Further study can be conducted to relate the short and long-term health issues among medical staff to poor indoor air quality.
Afficher plus [+] Moins [-]Identification and Characterization of Microplastics on the Surface Water in Laguna de Bay, Philippines
2023
Deocaris, C. C. | Fernandez, M. C. | Lee, A. R. | Miao, S. L. A. | Padolina, J. B. P.
Laguna de Bay is the largest lake in the Philippines. It is surrounded by developing cities that pollute the lake with plastics from different industrial and domestic activities. In the study, microplastics were collected from the lake’s surface water through three (3) collection points within the lake. The collection of microplastics was conducted from August 2018 to October 2018. About eight-hundred ninety (890) microplastics were collected and cataloged. Among the collection sites, ‘Brgy. Sampiruhan’ has the most microplastics, with a median of 15 ranging from 11-24 microplastics per 1000 L of lake water. On the other hand, ‘Brgy. Napindan’ has a median of 4 which ranges from 2-6 microplastics per 1000 L, and ‘Brgy. San Isidro’ has a median of 6 which ranges from 4-24 microplastics per 1000 L. Image analysis revealed that microplastics from this site were larger and angular. The color analysis shows signs of whitening and yellowing of the plastic materials, which suggests that the microplastics undergo photodegradation. Fourier-transform infrared spectroscopy (FTIR) found that most of the microplastics in the lake are made of polyethylene and its derivatives. Microplastics in Laguna de Bay show the continuous plastic pollution in the Philippines’ largest lake.
Afficher plus [+] Moins [-]The Potential of Phytoremediation to Treat Different Types of Wastewater - A Review
2023
Panday, Vijayant | K., Ananda Babu
Globally, with an increase in population, water demand is also increasing, but on the other hand, water availability is continuously decreasing due to various factors. Contamination of existing water bodies is the main factor for the freshwater shortage. Conventional methods are there to treat polluted water, but their construction and operational cost are very high. Phytoremediation is an economical, solar-driven, green plants (macrophytes) based, environment-friendly technology being researched worldwide. Many researchers contributed to identifying the potential of phytoremediation to treat different types of wastewater. Along the same line, an attempt has been made with this literature survey to contribute to technological advancement. The study results showed that water hyacinth plants could potentially treat almost all types of wastewater. Still, their use with other plants like Phragmites australis, Azolla filiculoides, Lemna minor, Typha latifolia, etc., as polyculture (mixed culture) could perform way better than the individual. It not only improves the efficiency of phytoremediation but also helps some plants to grow and perform for a long duration when used in mixed culture.
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