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Analysis of Watershed Characteristics of Nalagarh Watershed, Himachal Pradesh for Optimization of Recharge Structures and Management of Groundwater
2020
Reena Ahuja and Naval Kishore
The study involves the study of Nalagarh watershed in Himachal as a topographically delineated hydro-geological entity which is allowing the entire surface runoff of its sub-watersheds to channelize through defined streams and drainage network to certain points in the watershed. Geomorphic analysis of Nalagarh watershed has enabled the study of qualitative and quantitative parameters of the watershed for efficient utilization and optimizing the management of its surface and groundwater resources. As Nalagarh valley has recently witnessed the highest industrial growth in the district and State of Himachal Pradesh, the study becomes all the more impertinent. The watershed has been delineated into 13 micro watersheds, based on the geomorphic analysis. To use the surplus monsoon runoff, a detailed study has been carried out for the computation of utilizable runoff and the number of structures that can be planned for its utilization. To effectively plan the rainwater harvesting structures, the morphometric analysis has been done.
اظهر المزيد [+] اقل [-]Study on the Efficiency of the Synchronous Alkali-ultrasonic Pretreatment of the Low Organic Matter Sludge and its Influence on the Microbial Population in the Anaerobic Digestion System
2020
Shihu Liu, Lei He, Pengcheng Zhao, Xuejie He, Xingxing Zhuo and Jian Zhou
To solve the problem of the low anaerobic digestion efficiency of the minimal organic matter sludge, the study proposes the synchronous alkali-ultrasonic pretreatment technology of the low organic sludge. The research results show that the collaboration between alkali and ultrasonic has significant effects on pretreatment efficiency. The pretreatment efficiency of the sorts is as follows: synchronous alkaliultrasonic treatment > alkali-ultrasonic stepwise treatment > ultrasonic-alkali stepwise treatment > ultrasonic treatment > alkali treatment. The synchronous alkali-ultrasonic treatment system has strong processing effectiveness. Compared with the control group (the raw sludge), the concentrations of the supernatant SCOD and VFAs of the low organic matter sludge after the pretreatment increases by 15.4 times and 59.64 times respectively, and the supernatant that is easily biodegradable organic matter increases by 19.1%. The gas production after alkali-ultrasonic synchronous pretreatment of the anaerobic digestion system of the sludge increases 58% higher than the control group (without pretreatment ). The results of the high-throughput sequencing of 16S rRNA in the anaerobic digestion system of the sludge, at the genus level, show that the dominant functional bacteria in the system mainly includes vadinHA17, Peptoclostridium, Peptostreptococcaceae, Tissierella, Syntrophomonas, Synergistaceae and Aminobacterium. The dominant functional bacteria genera in the systematic archaea group mainly include Methanosaeta (70.33%), Unclassified (2.74%), Methanosarcina (15.49%), Methanobacterium (5.31%), Methanospirillum (2.18%), ARC26 (1.04%), Methanobrevibacter (1.62%). The abundance of functional bacteria at the genus level was higher than that in the control group.
اظهر المزيد [+] اقل [-]Causes of Air Pollution in Bangladesh’s Capital City and Its Impacts on Public Health
2020
Kudrat-E-Khuda (Babu)
Air is one of the precious natural resources which is essential for living beings. Pollution in the urban areas like Cairo, Delhi, Mexico and Dhaka far surpasses the acceptable limits set by the World Health Organization (WHO). Urban air pollution in the South Asian region is approximated to cause more than 300,000 deaths and billions of cases of respiratory disease per year. In Bangladesh, about 200,000 people die each year due to air pollution as the WHO estimates in 2018. The air in Dhaka city, the capital of Bangladesh, has worsened to a level that the city has been identified as one of the most polluted cities in the world. Taking the problem with utmost importance into consideration as it is related to public health, air pollution is being treated as one of the priority issues. The level of pollution in the roadside environment is deeply connected with the density of motor vehicles plying on the roads. This situation is expected to worsen further in the upcoming days due to the increasing number of motor vehicles resulted from rapid economic growth and industrialization. This paper aims to provide the present status of air pollution in Dhaka city and some specific recommendations for making the city a better living place by reducing its air pollution.
اظهر المزيد [+] اقل [-]An Evaluation of the Green Performance of Chinese New Energy Enterprises From the Perspective of Social Responsibility
2020
Le Yang and Yue Zhang
To evaluate the green performance of Chinese new energy enterprises, a performance evaluation system entailing four dimensions of social responsibility, management of liabilities, market-related responsibility, safety, and environmental responsibility was constructed. This system was subsequently applied to analyze and assess the green performances of 18 energy enterprises in China with their social responsibility. Results show that the green performances of most of the energy enterprises with social responsibility are hierarchically based. Specific countermeasures were proposed for promoting the health of energy enterprises and their sustainable development. These measures to be implemented by energy enterprises include establishing and perfecting systems for managing liabilities, sustaining the market, strengthening responsibility for security, and making diligent efforts to fulfil their environmental responsibilities.
اظهر المزيد [+] اقل [-]Bioremediation of Diesel Oil Contaminated Soil by a Novel Isolated Potential Oil Degrading Staphylococcus argenteus MG2 Bacteria Using Bio Stimulation Method
2020
Mahima Golani and Krishnan Hajela
The potential oil-degrading isolate Staphylococcus argenteus MG2 was used for bioremediation of oil-contaminated soil. Hydrocarbon degradation by the soil microorganisms was evaluated in a soil experimentally contaminated with diesel oil. The effects of six different biological treatments on hydrocarbon degradation were determined during a 50 days incubation period to evaluate biostimulation via inorganic fertilizers (NPK) or manure (compost) with and without inoculum of Staphylococcus argenteus MG2. Eight soil samples were used: (S) uncontaminated control soil; (CS) contaminated soil; (CSF) contaminated soil + N-P-K fertilizer; (CSC) contaminated soil + compost; (CSI) contaminated soil + Inoculum; (CSFI) contaminated soil + N-P-K fertilizer + Inoculum; (CSCI) contaminated soil + compost + Inoculum; (SCSCI) sterile (oil) contaminated soil + compost + Inoculum. Percentage of oil degradation during bioremediation treatment of 50 days was found to be (CS) - 32%, (CSF) - 70.80%, (CSC) - 75%, (CSI) - 84.40%, (CSFI) - 91%, (CSCI) - 93%, (SCSCI) - 94% respectively. Results showed that not only inorganic nutrients NPK and compost stimulated hydrocarbon biodegradation but inoculation of Staphylococcus argenteus MG2 also enhanced hydrocarbon degradation. The microbial count was found to be higher in SCSCI soil sample. The germination percentage and growth of leguminous plant (Vigna radiata) in the treated soil was also notably greater. It may be concluded that the Staphylococcus argenteus MG2 bacteria possess remarkable oil-degrading properties and can be effectively employed in the bioremediation of oil-contaminated soils and can be used for agriculture purpose.
اظهر المزيد [+] اقل [-]Haematological and Serum Biomarker Responses in Heteropneustes fossilis Exposed to Bisphenol A
2020
Bhawna Srivastava and P.B. Reddy
The present investigation was carried out for 21 days to explore the sub-lethal toxicity of bisphenol A (BPA) of concentration 0.714, 1.428 and 2.142 mg/L (1/10, 1/20 and 1/30 % of 96 h LC50) on haematological and serum biochemical parameters of Heteropneustes fossilis. Routine haematological parameters like total erythrocyte count (TEC), total leukocyte count (TLC), haemoglobin content (Hb), haematocrit (Hct), erythrocyte indices, total serum protein, alanine aminotransferase (ALT), and aspartate aminotransferase (AST), albumin, globulin, uric acid, and creatinine were examined as toxicological endpoints. The findings of this study revealed that BPA had a negative effect on both the haematological and serum biochemical parameters of Heteropneustes fossilis. The study revealed a significant decrease in red blood cell count, haemoglobin concentration and haematocrit percentage (anaemia) while white blood cell count showed a significant increase in all treatment groups (p < 0> 0.05). The results of serum biochemistry in BPA exposed fish showed enhanced serum AST, ALT, urea, uric acid and creatinine but decreased serum total protein and albumin. This might be due to the possible disruption of haemopoietic tissue or impairment of liver and kidney function. Based on the results, we conclude that BPA is toxic to Heteropneustes fossilis and its occurrence in the environment may threaten the health of aquatic species. Accordingly, it suggests that haematological and serum biochemical parameters could be effectively used as reflective bioindicators in ecotoxicological studies.
اظهر المزيد [+] اقل [-]Water Environment Quality Analysis Based on Information Diffusion Theory and Fuzzy Neural Network
2020
Hai-tao Chen, Ke-ke Xie and Wen-chuan Wang
Reservoirs play a key role in many infrastructure functions for people like flood control, irrigation, and water supply. In this work, we focused on the water quality evaluation model for Shimen Reservoir. Based on the monthly changes of factors such as pH, nitrate, ammonia nitrogen (NH3-N) and total nitrogen (TN) in 2013 and 2014, the information diffusion theory and fuzzy neural network technology were utilized to evaluate the water quality comprehensively. The probability distribution of these four factors in the reservoir was analysed and the water quality of the reservoir evaluated. The results show its reliability and these two methods can provide a basis for water quality control of Shimen Reservoir. Furthermore, the methods can be universally applied to the analysis and research of water quality in other regions.
اظهر المزيد [+] اقل [-]Physicochemical Properties of Jatropha podagrica Biodiesel Blends and Their Effects on Tractor Engine Performance and Emission
2020
S. Nuanual, P. Maneechot, P. Thanarak, A. Phuruangrat and S. Artkla
Jatropha biodiesel produced from Jatropha podagrica oil by alkaline-catalysed transesterification was blended with diesel in the ratios of 88:12 wt% (B88) and 12:88 wt% (B12). The fuel properties, consumption rate and exhaust gas emission characteristics of J. podagrica biodiesel, diesel and their blends were assessed. The results showed that J. podagrica seed oil have similar fatty acid profile with those of Jatropha curcas cultivated in Thailand and other South-East Asian countries. Blending of J. podagrica biodiesel and diesel enhanced the fuel properties of the blends, similar to those of the diesel. However, the B88 blend emitted lesser pollutants when compared to B12 and petrol diesel, making it very ideal for use as a promising alternative to the petrol diesel used in the mini tractor for farming activities. The results from the current study form a basis for further research on the use of B88 as a fuel source.
اظهر المزيد [+] اقل [-]Comparison of Structural Stability and Erodibility of the Purple and Loess Soils Based on Le Bissonnais Method
2020
Y. Wang, Z. Wu, F.T. Li, Y. Deng, X.L. Liang and G. Wang
This paper aims to study structural differences and anti-erodibility properties of purple and loess soils in hilly terrains of southern and northern China. Yoder’s method and Le Bissonnais method were used to determine the distribution of soil particle sizes, mean weight diameter (MWD), and geometric mean diameter (GMD). The sequences of water-stable aggregates in different sizes were as follows: On one hand, the sequence of purple soil aggregates was W2-5mm>W0.25-0.5mm>W0.5-1mm>W0-0.053mm>W0.053- 0.25mm>W1-2mm>W>5mm. On the other hand, the sequence of the loess soil was W0-0.053mm>W0.053- 0.5mm>W0.25-0.5mm>W0.5-1mm>W2-5mm>W1-2mm>W>5mm. Three LB treatments were carried out and the results were as follows: MWD and GMD of soil aggregates in the loess soil presented the trend of slow wetting (SW)>wetting stirring (WS)>fast wetting (FW), while those in the purple soil were WS>SW>FW. Under SW treatment, purple soil had higher erodibility factor (K) than loess soil, close to the result of Yoder’s method. Yet under WS and FW treatments, K values of purple soil were much lower than that of loess soil (P<0.05). A significant difference in K, MWD, GMD, and soil organic matter (SOM) values was found between purple soil and loess soil (P<0.05). Slope positions greatly influence MWD, GMD, SOM content for the two soils (P<0.01), and the interaction between soil type and slope position showed an extremely significant positive correlation to MWD and GMD (P<0.01). Our study indicates that, under different breakdown mechanisms, purple soil has a more stable structure and higher anti-erodibility than loess soil. The results of this study will provide a theoretical basis for further understanding of the erosion mechanism of the main soils in China.
اظهر المزيد [+] اقل [-]Biosorption of Manganese by Amended Aspergillus versicolor from Polluted Water Sources
2020
A.H. El Maghrabi, M.A. Marzouk, M.A. Elbably and M.E.M. Hassouna
This study deals with the adsorption capacity of the powder of Aspergillus versicolor (Ascomycota) as a bioadsorbent for the removal of manganese ion from polluted water samples. The effect of various experimental parameters such as the effect of pH, quantity of the fungus powder, contact time with the manganese (II) ion solution and its concentration on the biosorption capacity was conducted to optimize them. Potato Dextrose Agar (PDA) plates amended with 100 ppm of Mn(II) ions were used for growing the fungus isolates and standard spread plate method was applied. The plates were incubated at 27°C for 4 to 7 days, then the grown fungi were killed by adding 0.5 N NaOH, washed with doubly distilled water, dried out in hot air oven and finally ground into a very fine powder. The results verify that the optimum pH value for manganese biosorption was 6. The rate of adsorption of manganese by Aspergillus versicolor was very fast reaching a maximum within 15 min at 31°C. Maximum removal efficiency occurred on the use of 0.3 g A. versicolor powder. The maximum metal uptake was relatively observed at 90 ppm manganese concentration. Manganese removal process decreased with increasing metal concentration. The desorption study showed that manganese was recovered up to 81.53% using 0.1 N HCl rendering the possibility of the adsorbent regeneration. Experimental results have been analysed using a Langmuir and Freundlich adsorption isotherm models. Surface morphology study of A. versicolor powder using SEM analysis, assured its irregular surface nature.
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