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Recent Progress of Novel Porous Materials in Wastewater Treatment
2024
Deqi Kong, Hua Chen, Zhen Xiang and Bin Wang
Unavoidably, the expansion of industry causes the release of numerous heavy metals, radionuclides, and organic pollutants into the environment. Due to these pollutants, the extremely toxic, highly carcinogenic chemicals provide a serious risk to people and aquatic life. Wastewater pollutants must be removed to safeguard the ecology. A huge specific surface area, multiple binding sites, a plethora of functional groups, variable pore size, and simplicity of surface modification are just a few advantages of porous materials. They are considered viable candidate materials for the efficient and selective removal of contaminants from aqueous solutions in a range of difficult circumstances due to their benefits. This work reviews the characteristics, methods of functionalization, and ways of modification of many novel porous materials in recent years. The use of these porous materials in the treatment of wastewater was examined. The development potential of porous materials is finally summed up.
Afficher plus [+] Moins [-]Impact of Cadmium-Induced Stress on Physiological Traits with Induced Osmolyte and Catalase-Mediated Antioxidative Defense in Rice (Oryza sativa L.)
2024
J. Yomso and A. Siddique
Cadmium is one of the most carcinogenic and hazardous heavy metals on the earth for causes many serious diseases and disorders in the plant body. The presence of Cd in the soil is equally harmful to the production of rice crops and human beings. A pot experiment was conducted to analyze the consequences of cadmium-induced stress on the antioxidative defense system in rice plants. The assessment of antioxidative defense mechanism based on the cadmium-induced stress in the range of 100 to 300 ppm while the parameters, Chlorophyll Content Index (SPAD), nitrogen (%), relative water content (%), membrane stability index (%), proline content (μg.g-1), and catalase activity (nm H2O2 mg-1.min-1) were used. The highest reduction in the Chlorophyll Content Index (CCI), nitrogen (%), RWC (%), and MSI (%) was recorded at the highest concentrations of Cd Cl2 (300 ppm). However, at the same time, an increase in proline content (μg.g-1) and catalase activity (nm H2O2 mg-1.min-1) were also detected at all the intervals of the study. The activity of CCI, amino acid, and enzyme were presented in % increase/decrease over the control of Cd-induced stress in rice plants. The reduction (%) in CCI (SPAD) and RWC (%) was recorded maximum at 75 Days after transplanting (DAT), while nitrogen (%) and MSI (%) were recorded at 50 DAT. However, the increase (%) in proline and Catalase activity was maximum at 75 and 50 DAT.
Afficher plus [+] Moins [-]Impact of Small Anaerobic Digester on Household Economy of Bangladeshi Livestock Farmers
2024
N. Sultana, J. S. Khanam, K. S. Huque, B. K. Roy, N. Huda and M. K. Alam
An extensive survey was performed covering all the regions of the country to find out the overall impacts of bio-digester on the economy of livestock farmers. Five districts were selected; ten farmers with having bio-digester of 3.2 m3 on average and ten farmers who have no bio-digester were selected from each district. Through direct interviewing and farm monitoring, all farm characteristics, i.e., diurnal biogas production, power generation, cooking time, income and expenditures, farmer’s gross earnings, and manure management practices data were collected accordingly. Descriptive statistics and student t-test was made to express the comparison response of the farms by using XL and SPSS software. It was observed that the owners of anaerobic digesters earned significantly (p < 0.001) more than the traditional farmers by selling animals and biogas (1715 & 306; 1146 & 0.00 USD, respectively). Not only that, by selling milk and fresh manure, the owners of bio-digester harvested more (p < 0.05) annual income than non-bio-digester farmers (4162, 3408 & 60.91, 44.63 USD, respectively). Though the expenditure of farmers having digester was high, but in a single fiscal year, they earned more (p < 0.05) profit than the conventional farmers (USD 4329 & 2842, respectively). However, owners of bio-digester used 67.2 % of their produced manure for gas production. Regarding storing manure as biomass and using it for cooking purposes significant difference (p < 0.001) was observed that was also reflected in the total manure management system of a farm. The farmers having no bio-digester stored 71.95% of their total manure in solid form, whereas the farmers who had bio-digester only stored 20.4% of their manure, which made a significant (p < 0.001) difference. From the biogas chamber, in an average one farmer used a gas stove for 4-5 hours and a gas lamp for 6-8 hours, which saved at least the expenditure of 18 USD per month/household. The notable thing was that the bio-digester alone contributed 7% to those farmers’ gross economy by producing gas. It can be recommended that the rural householders could generate power by installing bio-digester and turn a small bio-digester as a beneficial avenue of their household economy.
Afficher plus [+] Moins [-]An Investigation in Temperature Data Analysis of Middle Atmospheric Variation from SABER Satellite
2024
E. Raghavendrakumar, V. Kamalakar and K. Sunil Kumar
This paper focuses on significant data analysis for middle atmospheric variations of height of 0 km 100 km. This data was downloaded from the SABER satellite NASA and analyzed with the help of MATLAB. The analysis includes the determination of propagation of wavelengths and oscillations for the semi-annual oscillation (SAO), Annual oscillations (AO), quasi-annual oscillations (QBO), EINIO southern oscillation (ENSO) from the period of Jan 2002 to Dec 2022 past twenty years data. The monthly mean Temperatures, monthly ozone deviations, and overall mean temperatures with standard deviations are estimated for the following altitude regions concerning troposphere (0-20km), stratospheric (21-50 km), mesospheric (51-90 km), and thermospheric regions (91-105 km). However, the results proved that the maximum temperature variations would affect the ozone depletion for the areas concerning the altitude height of 15-40 km region between troposphere and stratospheric in the temperature range of 260K, and average deviations are found in the order of 0.000010 μm for the troposphere region. The presence of harmful gases such as CO, CO2, NOx, H, and CH4 released from the automobile and powerplant industry may deplete the ozone layer and cause adverse effects.
Afficher plus [+] Moins [-]Hunting Resource Management by Population Size Control by Remote Sensing Using an Unmanned Aerial Vehicle
2024
S. Ivanova and A. Prosekov
The study was carried out on the territory of the Kemerovo region-Kuzbass (Western Siberia, Russia). The purpose of the study was to obtain information on the species diversity and population of big-game animals. The monitoring was carried out on the forest territories of the region’s administrative districts. In the course of remote sensing using an unmanned aerial vehicle, the presence of all types of animals under consideration, except for the bear, was recorded. The deviation of the population number determined using the traditional method of digital technologies varied up to 50%. It was established that environmental measures organized and carried out by the regional administration and hunting farms improved the situation and stabilized the population of the main group of game animals. It was found that when using a sufficiently high sensitivity of the thermal imager (the used thermal imager had a very high sensitivity class ≤ 60 mK at 300 K), long-haired animals, which are characterized by a lower intensity of thermal radiation (for example, wolves) are identified and recognized in the images. The larger the animal and the worse the thermal insulation layer (wool or feathers), the easier it is to identify it in infrared images and the lower the sensitivity requirements of thermal imagers. The ability to recognize and record smaller animals and birds requires additional research on existing technologies. Our research has confirmed the validity of digital remote monitoring methods for managing the wildlife of hunting farms and nature conservation areas of the Siberian Taiga territories.
Afficher plus [+] Moins [-]The Suitability of Fe3O4/Graphene Oxide Nanocomposite for Adsorptive Removal of Methylene Blue and Congo Red
2024
Viet Cao, Phuong Anh Cao, Duy Linh Han, Minh Tuan Ngo, Truong Xuan Vuong and Hung Nguyen Manh
In this study, Fe3O4/GO nanocomposite was synthesized by hydrothermal method and tested for its efficiency in removing methylene blue (MB) and congo red (CR) from water. The synthesized nanocomposite was characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The optimal values for MB and CR removal were determined to be pH 6.0, an adsorbent weight of 50.0 mg, and a contact time of 10 min. The adsorption isotherms of the contaminants on the nanocomposite were analyzed using the Freundlich model, indicating a heterogeneous distribution of active sites on the adsorbent surface. The highest adsorption capacity of MB and CR is 135.1 and 285.7 mg.g-1, respectively. Moreover, Fe3O4/GO nanocomposite recycled five cycles with proper adsorption capacity. Overall, the Fe3O4/GO nanocomposite holds great promise for efficient and sustainable water treatment, providing safe and clean water globally.
Afficher plus [+] Moins [-]Effect of Humic Acid Fertilizer on Mercury Release from Greenhouse Soils
2024
Z. Zhao, L. Y. Long, H. Gu and R. G. Sun
The elemental mercury (Hg0) release characteristics from the Hg-contaminated soil applied with Humic acid fertilizer (HAF) in the greenhouse were identified. The adsorption features of mercuric ion (Hg2+) on HAF under different reaction times and pH were investigated to elucidate the influencing mechanism of HAF on soil Hg0 release. Besides, the microstructure of HAF loading with Hg2+ was characterized by using Fourier transform infrared spectroscopy (FTIR) and scanning electron micrograph-energy dispersive spectrometry–EDS). The results showed that with the increasing HAF dosage, soil oxidation-reduction potential (Eh), and organic matter (SOM) content, as well as the decreasing soil pH, the soil Hg0 release fluxes showed a decreasing tendency. The soil pH, Eh, SOM, and total Hg content are the key factors that can affect the soil Hg0 release fluxes. The interior air temperature, light intensity, soil moisture, and soil temperature have little impact on soil Hg0 release fluxes when the greenhouse soil is applied with HAF. The HAF can immobilize Hg2+ and reduce its activity by surface precipitation and specific adsorption, then affecting the soil Hg0 release fluxes. The results of this study provide a basis for the application of HAF to reduce soil Hg0 release fluxes in the greenhouse of Hg-contaminated areas.
Afficher plus [+] Moins [-]A Short-Term Autoregressive Model for the Prediction of Daily Average NO2 Concentration in Nagercoil, Tamil Nadu, India
2024
P. Muthukrishnan and R. Krishna Sharma
Nitrogen dioxide (NO2) is one of the pollutants that can cause potential damage to the ecosystem. NO2 emitted from vehicles forms the primary precursor for ground-level ozone. In this study, an analysis of the daily average of NO2 concentration with meteorology measured for two years 2021 and 2022 is being carried out. It is evident from the analysis that NO2 concentration followed an apparent diurnal pattern with a maximum value in the morning hours and a minimum during the afternoon hours. Summer months recorded the highest, and North East Monsoon (NEM) recorded the lowest values of NO2. A statistically significant positive correlation was found between NO2 and Temperature. An autoregressive model was formulated to forecast the daily average values of NO2 concentration. Unit root test was performed to check the stationarity of the data points, which is important in determining trends and seasonal changes. From the model procedure, the order that best fits the data was identified as AR (4), in which the process has the current value based on the previous three values. The Akaike Information Criterion (AIC) and Schwartz Criterion (SC), which are estimators of prediction error for AR (4), are low. The Jarque confirmed the normal distribution-Bera test, which again approves the satisfactoriness of the model.
Afficher plus [+] Moins [-]Energy Requirement of Wastewater Treatment Plants: Unleashing the Potential of Microalgae, Biogas and Solar Power for Sustainable Development
2024
Urvashi Gupta, Abhishek Chauhan, Hardeep Singh Tuli, Seema Ramniwas, Moyad Shahwan and Tanu Jindal
Sustainable energy legislation in the modern world is the primary strategy that has raised the benchmark for energy and environmental security globally. The rapid growth in the human population has led to rising energy needs, which are predicted to increase by at least 50% by 2030. Waste management and environmental pollution present the biggest challenge to developing countries. The improvement of energy efficiency while ensuring higher nutritional evacuation wastewater treatment plants (WWTPs) is a significant problem for many wastewater treatment plants. Some treatment techniques require high energy input, which makes them expensive to remediate water use. Pollutants like chemical pesticides, hydrocarbons, colorants (dyes), surfactants, and aromatic compounds are present in wastewater and are contributing to other problems. Israel consumes 10% of the global energy supply, significantly more than other countries. The lagoon and trickling filters are the most widely used technologies in South African WWTPs, where the electricity intensity ranges from 0.079 to 0.41 kWh.m-3 (Wang et al. 2016). Korea and India use almost the same energy (0.24 kWh.m-3). An estimated one-fifth of the energy used in a municipality’s WWTPs is used for overall public utilities, and this percentage is anticipated to rise by 20% over the next 15 years owing to expanding consumption of water and higher standards. In this review paper, we examined the potential for creating energy-self-sufficient WWTPs and discussed how much energy is currently consumed by WWTPs. The desirable qualities of microalgae, their production on a global level, technologies for treating wastewater with biogas and solar power, its developments, and issues for sustainable development are highlighted. The scientific elaboration of the mechanisms used for pollutant degradation using solar energy, as well as their viability, are the key issues that have been addressed.
Afficher plus [+] Moins [-]Analysis and Characterization of Municipal Solid Wastes Generated in Ifugao State University Potia Campus: A Basis For Planning of Waste Management
2024
P. Latugan, J. J. Carabacan, G. Bonicillo, J. Cayog, M. Q. Eyawa, M. T. Cairel and J. M. Ngohayon
The end of the COVID-19 pandemic resulted in the total return of students and employees in Ifugao State University Potia Campus, a higher education institution located in Potia, Alfonso Lista, Ifugao, Philippines. However, the return of the pre-pandemic operations on campus caused problems in managing the generated municipal solid wastes. Hence, an analysis and characterization of the generated municipal solid wastes was conducted to determine important data that can be used for future waste management planning. The generated municipal solid wastes were gathered from the various waste generators within the campus for five consecutive days. The total generated municipal solid waste on the campus was about 140.10 kg.day-1, most of which was contributed by the canteens (20.86%). The generated municipal solid wastes were dominated by biodegradable waste (48.65%) and recyclable waste (37.26%). In addition, most of the generated municipal solid wastes were related to people’s food and beverage consumption behavior. The total volume of the MSW generated daily was about 5.647 m3. It is recommended that the campus create and enforce its waste management plan to specifically address the aforementioned characteristics of the generated municipal solid wastes.
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