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Analysis of Water Quality of Hatirjheel Lake, Dhaka, Bangladesh
2023
Pasha, A. B. M. Kamal | Mustafa, Syed Omayer | Rahman, S. M. Mahmudur | Abdullah, Muhammad | Chowdhury, Md. Azharul Haque | Parveen, Mahfuza
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.
Показать больше [+] Меньше [-]Sustainable Campus Policy Strategy in Estimating CO2 Emissions at the Universitas Negeri Semarang, Indonesia
2023
Sunardiyo, Said | Purwanto, P. | Hermawan, H.
In the fight against global warming, various options for reducing CO2 emissions are being implemented on campus. Furthermore, the management of campus sustainability at the Universitas Negeri Semarang (UNNES), Central Java, Indonesia, should be supported by accurate forecasts of electrical energy consumption. Therefore, this research aims to develop a predictive model to forecast the consumption of electrical energy in reducing CO2 emissions and to determine the factors triggering the increase. The prediction model is developed using Back Propagation Neural Network Artificial (BP-ANN) architecture. Furthermore, the data on the occupancy of lecturers and education staff as well as on students was obtained from the University's staffing and student affairs bureau. Climatic data such as temperature, humidity, wind speed, the duration of irradiation, and the average intensity of solar radiation were obtained per month from the Meteorology, Climatology, and Geophysics Agency of Semarang, Central Java for the 2013-2019 period as input data. The results of the empirical analysis showed an increase in electrical energy consumption from 2020 to 2025. In March, the consumption decreased but increased from April to June and decreased in July. It then increased until November and December, and it decreased every year. The results of CO2 emissions calculated by considering the emission factors from Indonesia's RUPTL-PLN in 2020-2025 showed an increase in electrical energy consumption and the ecological consequences affecting the campus area. Furthermore, the main factors causing the high consumption of electrical energy are the occupancy rate, lecturers, students, and campus employees, as well as local climate influences such as temperature, humidity, wind speed, duration of solar radiation, and intensity of solar radiation. Therefore, developing guidelines to reduce power consumption on campus should be a priority
Показать больше [+] Меньше [-]Pathogen Treatment in Single and Two-Stage Vertical Flow Wetland as a Potential Sanitation Technology for Rural India
2023
Patil, Prajakta Pratap | Yadav, Anant | Baragi, Lalita Vithal | Mutnuri, Srikanth
Vertical flow-constructed wetlands (VFCW) are well-established, cost-effective, and sustainable options for wastewater treatment. Along with organic matter removal, wetlands are helpful in the removal of microbial pathogens. This study focuses on understanding the bacterial pathogen removal efficacy of three different design types of VFCWs and understands the best designs for the efficient removal of pathogens in a tropical climate. The three wetlands studied for removal efficiency were (a) two-stage vertical flow constructed wetland (TSVFCW), (b) Single-stage vertical flow constructed wetland (SSVFCW), and (c) single-stage saturated vertical flow constructed wetland (SSSVFCW). Results revealed that all three types of wetlands were effective in removing pathogenic bacteria. Still, TSVFCW was found to be more efficient in pathogen removal (Total Coliforms, Shigella spp., Salmonella spp., Pseudomonas spp., Vibrio spp., Enterococcus faecalis) 7.04 ± 0.17, 6.53 ± 0.08, 4.0 ± 0.42, 7.67 ± 0.08, 5.73 ± 0.70 and10 5.23 ± 0.96 Log10 reductions respectively compared to SSVFCW (5.28 ± 0.18, 5.18 ± 0.09, 3.74 ± 0.74, 6.98 ± 0.01, 3.97 ±0.32, 4.74 ± 1.08 Log10 reductions respectively) and SSSVFCW (4.48 ± 0.46, 4.83 ± 0.15, 2.74 ± 0.44, 6.71 ± 0.03, 4.31 ± 0.49, 5.03 ± 1.20 Log10 decreases respectively). For abiotic factors (Chemical oxygen demand, total Kjeldahl nitrogen, and phosphorus) also TSVFW shows better efficiency (45 ± 8.7, 24.7±4.5 and 3.1, ± 0.2 g.m-2, respectively) than SSVFCW (12 ± 1.3, 7.6 ± 0.4 and 1.8 ± 0.2 g.m-2 respectively) and SSVFCW (6.3 ± 1.1, 7.7 ± 0.1 and 1.2 ± 0.1 g.m-2 respectively). However, the removal efficiency of both single-stage wetlands was comparable.
Показать больше [+] Меньше [-]Design and Development of Smart Irrigation System Using Internet of Things (IoT) - A Case Study
2023
Kumar, G. Sasi | Nagaraju, G. | Rohith, D. | Vasudevarao, A.
With India’s population growing at a rapid pace, traditional agriculture will have a tough time meeting future food demands. Water availability and conservation are major concerns for farmers. This paper aims to discuss the aspects related to designing and fabricating an automatic irrigation system using the Internet of Things (IoT) which will save the farmer’s time and money significantly. Human intervention in fields will be reduced. Changes in soil moisture are detected by soil moisture sensors and irrigation is automated using IoT. The proposed system is most economical for underdeveloped places because it is very cost-effective. Based on the soil moisture content, the sensor detects and sends signals to the node MCU, which activates the motor. When the plants receive enough water, the motor automatically shuts off. The user will be alerted about the soil’s moisture content through his mobile phone. The proposed smart irrigation system is implemented at our campus which conserves energy and water.
Показать больше [+] Меньше [-]Feasibility of Waste-to-Energy Plants for STT-PLN Campus Canteen
2023
., Pawenary | Larasati, Amelia Dwita | ., Suhdi | Wardhani, Rulyanti Susi
The pellets of waste produced by Society Electric [Listrik Kerakyatan (LK) 2] at the STT-PLN have not been efficiently utilized in terms of energy. The STT-PLN canteen consists of 14 stalls with an installed electricity capacity of 1300 VA, each with 12h of use/day. This study aimed to convert LK 2 waste pellets into electrical energy to supply electricity to the STT-PLN canteen. This research method uses quantitative methods, i.e., by calculating the amount of energy produced adjusted to the needs of the canteen. Gasification technology was chosen due to its high efficiency and lower emission impacts in the waste combustion technique. Based on the analysis, the gasifier engine that complies with this requirement was TG30-1 with a maximum capacity of 25 kVA and requires a flow rate of 10 kg.h-1 of waste pellets. The amount of waste pellets used for this plan was 120 kg.day-1. The assessment results of this plan indicated a net present value of IDR 302,218,609.33, an internal rate of return of 25.7983%, and a PBP of 5.66 years. Based on the economic analysis, the establishment of plants for the conversion of waste to power was declared feasible to operate.
Показать больше [+] Меньше [-]Corrosion Behavior of Petroleum Pipeline Steel in the Sulfur Ion Enriched Solution with Quinoline
2023
Li, Shanjian | Cui, Guotao | Wu, Panfeng | Feng, Yang
Localized corrosion is a serious, hazardous destroyer of steel petroleum pipelines meant for long-time use. However, previous studies on localized corrosion primarily focused on local corrosion morphology and corrosion rate of bulk metals because detecting the corrosion state of occlusive metals is difficult. Herein, we employ a simulating occluded battery unit to disclose the local corrosion behavior of the steel petroleum pipeline (N80 steel) in an occlusive S2–-enriched solution. After simulating localized corrosion in the S2–- containing corrosion solution using the occluded battery unit, the occlusive solution was acidified and the migration amount of S2– to the occluded area increased. Despite the increase of S2– concentration, the addition of quinoline corrosion inhibitor (0.8 wt%) still effectively impedes the corrosion of the occluded metal. Moderately raising the environmental temperature can stimulate the activity of the inhibitor and promote the inhibition effect. The quinoline corrosion inhibitor displays the maximum inhibition rate at an elevated temperature of 50°C. Meanwhile, a maximum over the temperature of 60°C-70°C will likely accelerate the failure of the inhibitor.
Показать больше [+] Меньше [-]Heavy Metal Removal from Contaminated Soil Using Soil Washing Techniques
2023
Resmi, G. | G. Thampi, Santosh | Chandrakaran, S.
Heavy metals are discharged into the soil around us from various anthropogenic sources and also by the use of fertilizers, pesticides, pharmaceuticals, etc. In most cases, industrialization can be pointed to as the reason behind soil pollution. Contamination of soil leads to large-scale environmental degradation and health impacts. Many investigators have studied techniques for removing heavy metals from soil. Soil washing is an emerging area that can be implemented for this purpose. Studies were carried out in the controlled conditions of a laboratory environment to determine the suitability of soil-washing techniques for removing lead from polluted land. The results showing the influence of various parameters in soil washing, such as duration of washing, molar strength of the solution used, the weight ratio of soil to wash solution, etc., are presented in this paper. Batch studies were conducted to investigate the performance of chelating agents such as Na2EDTA, HCl, HNO3 and CaCl2 with regard to the removal of lead from artificially contaminated locally available soil. Based on the batch studies, it is observed that the strength of the washing solution, the proportion of soil and solution, the period of agitation, etc. influence the removal of contaminants. Based on the studies, it is concluded that, while recommending soil washing using chelating agents for remediating lead-contaminated soils, it is essential to identify the influencing parameters and determine the optimum conditions so that higher removal can be achieved without any adverse effect.
Показать больше [+] Меньше [-]Evaluation of Biomass Solid Waste as Raw Material for Preparation of Asphalt Mixture
2023
Tao, He | Liu, Hongming | Yang, Jie | Sun, Tao
At present, the resource utilization of solid waste in China is facing prominent problems such as high production intensity, insufficient utilization, and low added value of products. The preparation of biomass composites from biomass solid waste and plastic solid waste reduces not only environmental pollution and energy consumption but also promotes the high-value utilization of solid waste. So, the characterization and preparation experiments of samples with two different biomass are carried out. The wheat straw fiber and corn straw fiber were added into the bio-asphalt mixture with the content of 0.1%, 0.2%, 0.3%, and 0.4%, respectively, with the content of 9% and 12% bio-heavy oil. The physical properties and rheological properties of asphalt were analyzed and evaluated by three indexes and a dynamic shear rheological test. Through the rutting test and immersion Marshall test, high-temperature performance and biological asphalt mixture’s water stability were evaluated. The results show that straw fiber can improve bio-asphalt mixture’s road performance, especially the performance of high-temperature rutting. When the fiber content of bio-asphalt with 9% bio-heavy oil content is 0.3%, the physical properties and rheological properties of bio-asphalt are the best. Corn straw fiber’s influence on bio-asphalt mixture was better than that of wheat straw fiber.
Показать больше [+] Меньше [-]The Influence of Geographical Factors on Polyploidy in Angiosperms with Cartographic Evidence from the Northwestern Himalayas: A Review
2023
Tiwana, Anupreet Singh | Thummalakunta, Siva Prathap | Gupta, Saurabh | Singh, Vijay | Kataria, Ramesh Chand
The review paper comprised the impact of geographical and environmental factors on polyploidy and vice versa. The review covers different effects of geographical factors, like spatial isolation, altitude, and local climate on polyploidy, and the behavior of polyploid(s) in abiotic factors, such as temperature and light with a few examples of northwest Himalayas. The paper concludes that polyploid plants behave differently in environmental conditions, as polyploids are more prominent in higher altitudes, colder environments, and nutrient-rich soil than diploid progenitors, but have a mixed distribution in different geographical conditions. Further, polyploidy is more common among perennials than annuals, while niche differentiation depends more on the local environment. The virtual case study results from North and North Western India have been shown with the help of ArcGIS online software. The scrutiny of spatial distribution on maps highlights the fact that polyploidy is still a complex research puzzle with interesting perspectives.
Показать больше [+] Меньше [-]Pattern Characterization of Meteorological Drought Using Multivariate Drought Index Over Mirzapur in Middle Gangetic Plains of India
2023
Gond, Shivani | Gupta, Nitesh | Dikshit, P. K. S. | Bihari Dwivedi, Shyam
Droughts and floods have been occurring at a higher frequency in recent decades. The rapid transition between them magnifies the socio-economic consequences of these catastrophes relative to the effects of the individual occurrences of the extreme event. This study examines the temporal variability of meteorological drought and wet event characteristics occurring over Mirzapur (Uttar Pradesh), India. The Standardized Precipitation Evapotranspiration Index (SPEI) is applied to monthly water balance at scales 3, 6, 9, and 12 months to estimate the meteorological drought and wet events from 1971 to 2018. Drought and wet event characteristics such as the number of drought/wet events, severity, duration, and intensity are estimated using run theory over SPEI output. While characterizing the pattern of trends over the historical time period, variable-sized cluster analysis (VSCA) allows the detection of multiple change points as opposed to the Mann-Kendall (MK) test, which produces a monotonic trend for the entire time period. The VSCA technique accounts for drought variability and depicts the pattern’s evolution across the period under consideration. Station-scale drought data from Mirzapur, Uttar Pradesh (UP), India, were used in the procedure. VSCA allows for the detection of many change points while describing the pattern of drought trend throughout a historical period, as opposed to the usual Mann-Kendall (MK) test, which provides a monotonic trend for the whole time. As a result, VSCA demonstrated the MK test compatibility.
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