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Susceptibility Evaluation of Debris Flow Disaster in Plateau Hydropower Cascade Development Reservoir Area
2023
Feng Yang, Xudong Hu, Zhenyao Xia, Lei Cui and Qi Yang
The Rumei Hydropower Station is a typical cascade hydropower development project in a plateau area. The dam site is located in an area with complex topography, lithology, and geological structure. Geological disasters are developed in the area, mainly debris flow. Thus, taking the dam site and the surrounding areas as key evaluation objects, the engineering geological characteristics, geological environment characteristics, and the susceptibility and risk of geological disasters that may be caused are predicted and evaluated. The main methods used in this assessment are the binary logistic regression model and expert evaluation. The results show that the susceptibility to geological disasters is small and medium. The results of this study could provide a scientific basis for the rationality of the general layout and site selection of the project construction in the plateau water elevator level development reservoir area.
Afficher plus [+] Moins [-]A Novel Green Approach for Lead Adsorption and Isotherm Evaluation
2023
M. Dharsana and J. Prakash Arul Jose
Environmental damage due to the discharge of organic pollutants and heavy metal toxins has become a major topic of concern for the past couple of years. Using just a natural adsorbent to solve wastewater concerns has lately gained popularity as an ecologically acceptable solution that encourages long-term growth. A range of approaches, including adsorption to the surface of agricultural leftovers, have been used to minimize heavy metals in an aqueous medium. Lead is amongst the most hazardous and widely discovered toxic substances in industrial waste. Citrus limetta peel powder, Banana peel powder, and Betel leaf powder were chosen as adsorbents in this study to absorb synthetic lead from an aqueous solution since they are low-cost materials. Our research aims to find natural bio-sorbents that can remove highly hazardous Pb2+ ions from aqueous solutions. The importance of contact time, concentrations, adsorbent-based dose, and pH in the adsorption process is investigated. The adsorption rate for betel leaves, Citrus limetta peel, and banana peel was 5, 10, 15, 20, and 25 g.L-1. Citrus limetta peel (10 g.L-1), banana peel (5 g.L-1), and betel leaf (5 g.L-1) provide the highest lead adsorption. Material characterization is used to determine the lead nitrate process in lead adsorption. The capacity of the lead-adsorbing substances to achieve adsorption equilibrium was assessed and estimated using linear Freundlich and Langmuir isotherms, with the experimental data fitting the Freundlich isotherm models.
Afficher plus [+] Moins [-]Effect of Geographic Altitude on Carbon Stock in two Physiographic Units of the Reserved Forest of the Universidad Nacional Agraria de la Selva
2023
M. Reategui, D. Reategui, E. Morales, R. Reategui and C. Aguirre
The objective of the research was to evaluate the effect of geographic altitude on the carbon stock in two physiographic units of the Reserved Forest of the Universidad Nacional Agraria de la Selva, Tingo Maria-Huanuco. The methodology used was the field manual for the remeasurement and establishment of plots of the Amazon Forest Inventory Network (RAINFOR), for which 2 hectares were permanently established (one hectare in low and high hills) in which the diameter (greater than or equal to 10 cm) and the height of the trees were measured. Finally, the density of the wood was obtained from previous studies. The pantropical model formula was used to estimate the carbon stock. The results show that geographic altitude significantly affects carbon stock (p < 0.05) in low and high-hill forests, concluding that this may be due to differences in meteorological variables such as precipitation, temperature, and humidity.
Afficher plus [+] Moins [-]Self-Healing and Thermomechanical Properties of Activated Carbon Pyrochar Derived from Municipal Mixed Plastic Waste Pyrolysis with Self-Healing Epoxy Vitrimer Composites
2023
Krishna Moorthy Rajendran, Bhawna Yadav Lamba and Deepak Kumar
An ecological vitrimer is being developed using activated carbon pyrochar from municipal mixed plastic waste pyrolysis into an epoxy composite. Durable vitrimeric materials may be created by adding pyrochar to polymeric composites. Due to their ductility, reusability, and recyclability, vitrimeric materials have become popular and reliable materials. As a result, the self-healing temperature of composite vitrimers is lower via disulfide exchanges than that of virgin epoxy vitrimers. Additionally, compressive studies have been used to study self-healing capacities, and modulus variations have been used to highlight changes in the healing efficiency of the materials.
Afficher plus [+] Moins [-]Analysis of Water Quality of Hatirjheel Lake, Dhaka, Bangladesh
2023
A. B. M. Kamal Pasha, Syed Omayer Mustafa, S. M. Mahmudur Rahman, Muhammad Abdullah, Md. Azharul Haque Chowdhury and Mahfuza Parveen
The study assessed the status of water quality parameters for an urban water body (Hatirjheel Lake) in Dhaka, the Capital city of Bangladesh. Nine different water samples were collected from nine points of the lake during the dry season in January 2021. Water quality parameters such as pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), total alkalinity, total acidity, total hardness, Ca2+ hardness, free CO2, and dissolved oxygen (DO) were determined for the samples. The status of the parameters is pH (6.51-7.05), EC (510-600 μS.cm-1), TDS (450-590 ppm), TSS (0.0-0.034 mg.L-1), total alkalinity (80-392 mg.L-1), total acidity (224-500 mg.L-1), total hardness (348-452 mg.L-1), Ca2+ hardness (74-162 mg.L-1), free CO2 (730-1170 mg.L-1), DO (2.7-5.5 mg.L-1). However, the DO value at some points of the lake is too less (2.7 mg.L-1 and 3.7 mg.L-1) than the standard value (> 5-6 mg.L-1) of ECR, DoE, which might not be healthy for any water body and aquatic ecosystem. Other water quality parameters are within the permissible limit of WHO and ECR, DoE.
Afficher plus [+] Moins [-]Efficiency of Paecilomyces variotii in Bioremoval of Reactive Black Dye from Tannery Effluent
2023
Priya Chokkalingam, Mahi Anamalagundam, Chaithanya Lahari, Shreya Singh, G. Mohan Kumar and Rajeswary Hari
The present work investigates the efficiency of Paecilomyces variotii upon degrading Reactive Black dye which has been termed a recalcitrant variety of synthetic dye. In this research, initially a predominant fungal species, Paecilomyces variotii was isolated from the tannery effluent sample. The study was carried out by assessing the ability of fungi to decolorize the dye under various parameters like pH (5,7 and 9), Temperature (7°C, 30°C, and 45°C), Dye concentration (200, 300, and 400 mg/L) for different incubation or exposure time interval (3, 5 and 7 days). From the experimental study, it was found that Paecilomyces variotii showed a maximum percentage of dye decolorization at 7°C at pH 9 with 75%, at 30°C at pH 7 with 85%, at 45°C at pH 5 with 82% and a maximum period of incubation with 7 days in 200 mg.L-1 concentration. This result conveys that the strength of Paecilomyces variotii in decolorizing the synthetic dye is effective at a moderate temperature with neutral pH for maximum exposure time. So Paecilomyces variotii could be a good candidate of choice for the biodegradation of various synthetic dyes when manipulated wisely. Also, the result sparks a positive attribute toward decreasing industrial wastewater pollution.
Afficher plus [+] Moins [-]Utilization of Waste Glass for Enhancement of Chemical Properties of Concrete
2023
Jagriti Gupta, A. S. Jethoo and Nandeshwar Lata
The world is facing a huge problem of waste generation; among these, solid waste in the form of glass has become a prime concern for the environment. The composition of the glass is silica-based, and its utilization in the preparation of concrete can be an efficient step in the direction of sustainable development by reducing the cement content. The formation of secondary calcium silicate hydrates (C-S-H) could take place due to the pozzolanic reaction of the fine ground glass with the cement. TGA techniques were used in this research to investigate the chemical properties of the waste glass, and later, these were compared with the properties of the cement. By keeping a constant w/b ratio for all the replacement levels from 0% to 35%, the evaluation of the workability and compressive strength were done. The evaluation showed that workability increased with an increase in the content of the waste glass. With 7 and 28 days cured samples, the strength and chemical investigation were conducted on the samples prepared with the same mix design. Constant Dose of superplasticizer used by weight of cement for mixes as 0.8%. Compared with the control sample, The level of replacement of waste glass to cement as 30% has depicted the augmentation in the compressive strength. Thus, the use of waste glass was found to be cost-effective and an environment-friendly solution for the sustainable development of concrete.
Afficher plus [+] Moins [-]A Coupled Study on Carbon Emission Assessment and Emission Reduction Coupling of Tourism Activities in Beautiful Countryside Taking Zhahan Village, Qiongzhong County, Hainan as an Example
2023
Liping Zhu, Yadong Zhou and Qing Li
Taking Zhahan village in Qiongzhong County, Hainan, as an example, and based on its 160,000 tourist arrivals in 2019 and taking into account the real circumstances of Hainan, this research composes the emission models of carbon emissions from tourism transportation, tourism accommodation, tourism catering, other tourism activities and pollutants in this village. The outcomes indicate that Zhahan village's tourism catering consumes the most energy and emits the most carbon, accounting for 53.95% of all carbon emissions. Furthermore, the emission of tourism accommodation is the second, occupying 24.13%. Then, its tourism waste emission is the third, constituting 13.61%. In addition, its annual sewage discharge from tourism activities amounts to 15,144 t. This article promoted 1MW photovoltaic and 10 square solar hot water in the entire village, scientifically developing the evaluation system of rural tourism carbon emission, and making a low carbon brand of emission reduction coupling. The research and operation can be replicated and extended to enable the harmonious development of tourism development and organic unity of energy resource utilization.
Afficher plus [+] Moins [-]Improved Large-Scale Ocean Wave Dynamics Remote Monitoring Based on Big Data Analytics and Reanalyzed Remote Sensing
2023
Subhrangshu Adhikary and Saikat Banerjee
Oceans and large water bodies have the potential to generate a large amount of green and renewable energy by harvesting the ocean surface properties like wind waves and tidal waves using Wave Energy Converter (WEC) devices. Although the oceans have this potential, very little ocean energy is harvested because of improper planning and implementation challenges. Besides this, monitoring ocean waves is of immense importance as several ocean-related calamities could be prevented. Also, the ocean serves as the maritime transportation route. Therefore, a need exists for remote and continuous monitoring of ocean waves and preparing strategies for different situations. Remote sensing technology could be utilized for a large scale low-cost opportunity for monitoring entire ocean bodies and extracting several important ocean surface features like wave height, wave time period, and drift velocities that can be used to estimate the ideal locations for power generation and find locations for turbulent waters so that maritime transportation hazards could be prevented. To process this large volume of data, Big Data Analytics techniques have been used to distribute the workload to worker nodes, facilitating a fast calculation of the reanalyzed remote sensing data. The experiment was conducted on Indian Coastline. The findings from the experiment show that a total of 1.86 GWh energy can be harvested from the ocean waves of the Indian Coastline, and locations of turbulent waters can be predicted in real-time to optimize maritime transportation routes.
Afficher plus [+] Moins [-]Research on the Law of Stress of Polychlorinated Naphthalenes (PCNs) on the Physiological Ecology of Bluegrass (Poa annua L.)
2023
Chen Laiyi, Song Yundi, Li Yue, Jiang Lei, Wang Yi, Wang Song and Hou Wei
This paper takes Poa annua L. as the research object and studies the law of physiological and ecological stress of 1-Chloronaphthalene (CN-1) and Octachloronaphthalene (CN-75) by using various physiological and biochemical indexes of Poa annua L. cultivated with soil under the stress of CN-1 and CN-75 of different concentrations. According to the research, the chlorophyll a and b first increase and then decrease with the increase of the concentration of CN-1, and continue to decrease with the increase of CN-75; Soluble sugar and soluble protein in plants decrease first and then increase with the increase of CN-1, and continue to decrease with the increase of CN-75; MDA in plants increases first and then decreases with the increase of the concentration of CN-1 and CN-75. The proline content in plants also increases first and then decreases with the increase of concentration of CN-1 and CN-75. Based on the research, it can be seen that the tolerance of the plant to CN-75 is not good as to CN-1.
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