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Selection of White-Rot Fungi for Decolorization of Palm Oil Mill Effluent and Evaluation of Biodegradation and Biosorption Processes
2024
Sanhathai Ridtibud, Nuttika Suwannasai, Apichaya Sawasdee, Verawat Champreda, Cherdchai Phosri, Sarper Sarp, Nipon Pisutpaisal and Siriorn Boonyawanich
Ten species of white-rot fungi were evaluated for their ability to decolorization of palm oil mill effluent. The highest decolorization efficiency was found with Trametes elegans (PP17-06), followed by Ganoderma sp.2 (PW17-06) and Ganoderma sp.2 (PW17-177), respectively. T. elegans was further evaluated for the long-term performance of decolorization for 24 d. The optimal retention time for the decolorization was 8 d, with a color removal efficiency of 47.7%. Beyond 18 d of incubation, decolorization efficiency was reduced due to the autolysis of enzymes. During the biodegradation process, manganese peroxidase enzyme activities reached a maximum of 36.03 U.L−1. However, no significant laccase and lignin peroxidase activities were observed. T. elegans was also assessed for decolorization performance through biosorption on mycelial biomass. The synthesis of the enzyme was prevented by exposing the mycelium to HgCl2. Within an optimal contact time of 2 d, decolorization efficiency reached 12.5% with ADMI reduction from 4259.0 (±20.1) ADMI to 3727 (±104.04) ADMI. Results indicate that the adsorption capacity was reached at this time, and no significant color removal can be achieved by biomass. Results obtained in this study showed the potential of T. elegans in decolorizing palm oil mill effluent.
显示更多 [+] 显示较少 [-]Urban Indian Environment in the Context of a Pandemic
2024
Abhijith. S., Akshara S. N. and P. P. Nikhil Raj
The spread of the Coronavirus disease 2019 (COVID-19) has impacted human life severely since November 2019. The urban centers in the world, especially, were highly affected by the diseases. Several socioeconomic and environmental factors probably enhanced the spread of the pandemic and consequent mortality. Many studies examining environmental factors, such as air quality, in urban centers indicate the roles of those factors in the spread of diseases and consequent mortality. However, other socioeconomic factors that directly or indirectly elevate the mass death of people are seldom studied. The present study explores the socioeconomic factors and air quality influencing COVID-19 deaths in urban India. We randomly selected 19 Indian cities and collected each city’s socioeconomic and air quality data from reliable and open sources. The data were analyzed using multivariate data analysis techniques using R statistics. The results showed significant positive relationships, population, and total area of the urban centers.
显示更多 [+] 显示较少 [-]Effective Utilization of Bio and Industry Wastes to Produce Thermal Insulation Concrete: A Novel Solution for Energy-Saving Buildings
2024
Jerlin Regin, Maria Rajesh Antony, Raya Said Mohammed Al-Zaabiya, May Darwish Ali Al Balushi, Hamdah Ali Ahmed Al Shehhi, Nooralsnaa Abdallah Mohammed Al-Farsi and Athari Khalifa Handi Al-Saadi
The research addressed the effective and sustainable ways to enhance the thermal insulation properties of concrete without compromising its structural integrity. Traditional methods of enhancing thermal insulation in buildings, such as using thick layers of insulation materials, can be costly and may not always be practical in certain settings. Additionally, the disposal of waste materials such as date palm fiber, shopping plastic bags, and thermocol beads presents an environmental challenge. Therefore, this study aims to investigate the potential use of these waste materials as additives in concrete to improve its thermal insulation properties while also providing a sustainable solution for waste disposal. Date palm fiber is a natural material that is widely available in the Gulf region. Plastic bags are a huge waste from the shops every day, and from the packing materials, this thermocol is a huge waste product. We have to recycle it very efficiently to protect the environment. Three types of special materials, such as thermocol beads (30%), date palm fiber (3%) & shopping plastic bag fiber (3%), were tested in this research. Thermocol beads, when used, reduce their strength and increase the thermal resistance of concrete, while date palm fiber and shopping bag waste fiber, when used, increase the strength of concrete and also increase the thermal resistance of concrete, so it is an excellent reinforcing material and thermal barrier for shopping plastic bags fiber and date palm fiber. Based on this research result, when thermocol beads are used, they prevent heat by 42 percent, while when added with date palm fiber and plastic fiber, they also block heat by an average of 30% percent; thus, all three ingredients are considered excellent thermal insulation material. The reduction in thermal conductivity was attributed to the formation of air voids and the low thermal conductivity of the waste materials. The density of the concrete decreased with the addition of the waste materials. The study suggests that the incorporation of date palm fiber, shopping bag waste fiber, and thermocol beads can be an effective way to enhance the thermal insulation properties of concrete while also providing an environmentally sustainable solution for waste disposal. It will boost green energy technology in the construction industry.
显示更多 [+] 显示较少 [-]A Facile Method for Synthesis of α-Fe2O3 Nanoparticles and Assessment of Their Characterization
2024
Paramjeet Dhull, Rajesh Kumar Lohchab, Mikhlesh Kumari, Kulbir Singh, Anil Kumar Bhankhar and Shaloo
Recently, magnetic nanomaterials have gained much attention from researchers because of their various unique physical and chemical properties and usage in a wide range of technological aspects. In this study, the synthesis of α-Fe2O3 nanoparticles was performed by a simple co-precipitation method. The synthesis of α-Fe2O3 nanoparticles was carried out by mixing ferric nitrate and oxalic acid in an aqueous solution followed by evaporation, resulting in the solution’s dried form. The synthesized nanoparticles were analyzed by XRD, FTIR, Raman spectra, SEM-EDX, DSC, BET, and Zeta potential for detailed examination of the morphology, structure, and other physicochemical characteristics. The XRD results confirmed that the nanoparticles formed were Hematite (α-Fe2O3) after the evaluation of obtained spectra compared to the Joint Committee on Powder Diffraction Standards Database (JCPDS). The FTIR spectra showed various bonds among functional groups, O-H bending, Fe-O group, and within-vibration bonds. The phase study of the α-Fe2O3 nanoparticles was performed by using Raman spectroscopy. SEM depicted a sphere-like or rhombohedral (hexagonal) structure, and the EDX spectrum confirmed the peaks of iron and oxygen.
显示更多 [+] 显示较少 [-]Feasibility Analysis of Municipal Wastewater Reinjection Technology
2024
Haijie Hu, Huan Zhang, Lei Han, Le Zhang, Tao Yu and Chengtun Qu
To study the feasibility of using municipal sewage as a reserve water source for oilfield reinjection, the water sample treated by the municipal sewage treatment plant and the produced water of the Chang 2 reservoir were taken as the research objects. Through the analysis of water quality and compatibility, the optimal ratio of reinjection water samples was determined. At the same time, the clay swelling experiment and reservoir damage experiment were carried out. The experimental results show that the salinity of municipal sewage is low, and the content of scale ions is low. When the ratio of produced water to municipal sewage is 7:3, the scale formation amount can reach 42.5 mg.L-1, and when the scale inhibitor is added, the scale formation amount can be reduced to 10.4 mg.L-1. The mixed water sample will not cause clay expansion. Meanwhile, Chang 2 reservoir is moderately weak water sensitive and weak acid sensitive. The oil content, suspended solids content, and median particle size of the mixed water sample during reinjection should be controlled at 5 mg.L-1, 5 mg.L-1, and 5 μm to ensure that the reinjected water sample does not cause damage to the reservoir.
显示更多 [+] 显示较少 [-]Determinants Influencing the Environmental Impact Assessment Compliance Rate by Industries in Aba City, Southeast, Nigeria
2024
C. Sam-Amobi, O. J. Ubani, K. Efobi and Nathan Ajukwara
A United Nations (UN) report on the severity of pollution in cities around the world in 2020 rated Aba City, Nigeria, as the most polluted city in the world. This has become a source of worry and embarrassment for environmental policymakers in the country. The matter of whether industries are efficiently managing their wastes came to the fore, and policymakers questioned the compliance of these industries with environmental laws and Environmental Impact Assessment (EIA) guidelines and the reasons behind the seemingly non-compliance of the industries with these guidelines. The study aimed to investigate the determinants that influence compliance with EIA guidelines by industries in Aba. A survey research method was employed in the study. Questionnaires and interviews were also used to elicit data from industrialists and environmentalists in the study area. 384 industries were sampled in the study. Principal Component Analysis was used to test the hypothesis. The study revealed seven factors that influenced the compliance rate of EIA guidelines by industries, and they include weak public participation (65.5%), ignorance (54.5%), an effective legal system and legislation (42.4%), the cost of compliance (40.5%), weak coordination along the line of departments (town planning officers and consultants) (35.5%), delay in approval (30.5%), and limited scope (28.9%). It was recommended that the government strengthen the legal system as it relates to the implementation of EIA; then, there is a need to involve affected stakeholders in the preparation of EIA documents.
显示更多 [+] 显示较少 [-]Sustainability Analysis of Landfill Cover System Constructed Using Recycled Waste Materials by Life Cycle Assessment
2024
G. Sanoop, Sobha Cyrus and G. Madhu
The sustainability of using industrial by-products for the construction of landfill cover was determined using Life Cycle Assessment (LCA). LCA was carried out on four materials: sand- bentonite mix, red earth- bentonite mix (amended soil), Waste Foundry Sand (WFS)- Bentonite mix, and WFS- marine clay mix. The former two are commonly used cover soils and the latter two are alternative materials proposed. Environmental impacts based on the extraction of resources, processing, transportation to the site, and site preparation were considered using the ‘cradle to site’ approach. Analysis was carried out in OpenLCA software using the ReCiPe (H) Midpoint method of impact assessment. Required data for analysis was taken from the Ecoinvent database supplemented with inputs from a field survey. The use of WFS in landfill cover systems was found to be sustainable using LCA studies when compared to conventional materials.
显示更多 [+] 显示较少 [-]Passivation Effect of Corn Vinasse Biochar on Heavy Metal Lead in Paddy Soil of Pb-Zn Mining Area
2024
M. Xiong, G. Q. Dai, R. G. Sun and Z. Zhao
The in-lab incubation experiments were conducted to identify the passivation effect of corn vinasse biochar, which was prepared at different temperatures, on heavy metal Pb in paddy soil of the Pb-Zn mining area. The results showed that after 30 days of biochar amended to the soil, the soil pH and organic carbon content increased by 2.72%-8.47% and 27.79%-65.26%, respectively. The CO32- and OH- contained in corn vinasse biochar could react with Pb and generate carbonate and hydroxide of Pb. In comparison with the treatment control, the bioavailable fractions of Pb were reduced by 26.6%, 23.30%, 26.95%, and 35.33%, respectively, in biochar-amended treatments. Exchangeable fractions of Pb decreased by 21.50%, 21.33%, 22.58%, and 22.58% for the treatment 3% (300°C), 6% (300°C), 3% (600°C), and 6% (300°C) corn vinasse biochar, respectively, compared with the treatment control. As a whole, corn vinasse biochar could effectively promote the transformation of Pb in soil from the exchangeable fractions into the Fe-Mn oxide-bound fractions and residue fractions, with a significant passivation effect for Pb in soil and more effective passivation by high-temperature preparation and increased dosage of biochar.
显示更多 [+] 显示较少 [-]Enhancing Enzymatic Hydrolysis and Delignification of Sugarcane Bagasse Using Different Concentrations of Sodium Alkaline Pretreatment
2024
Arti Yadav, Pushpa Rani, Deepak Kumar Yadav, Nisha Bhardwaj, Asha Gupta and Narsi Ram Bishnoi
Lignin, being highly resistant, needs to be eliminated in the process of extraction of soluble reducing sugar and bioethanol production from lignocellulosic biomass. In the present work, pretreatment of sugarcane bagasse (SCB) was performed using NaOH of various concentrations (1-5%) to facilitate delignification. The hydrolysis efficiency of pretreated SCB was evaluated at different reaction times by the production of reducing sugar using the Cellic CTec2 enzyme. The maximum cellulose content of 57.6% and lignin removal of 62.04% were observed with 2% sodium hydroxide at 121°C autoclaved for 60 min. The hemicellulose content decreased with increasing NaOH concentration with the maximum decrease of 13.6% from native bagasse having 26.5% xylan content. The microstructure, morphology, and chemical composition of SCB were analyzed using Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform InfraRed (FTIR), and XRD. The hydrolysis with 10 FPU.g-1 of enzyme at 48 h of reaction time shows a maximum yield of 12.34 g.L-1 corresponding to 55.53 ± 0.45% at 2% NaOH pretreated SCB. This study claims that lignin components exhibited the highest susceptibility to NaOH pretreatment, which directly affects enzymatic hydrolysis.
显示更多 [+] 显示较少 [-]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.
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