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Performance Study of Cellulose Acetate Blended Polyvinylchloride Membranes
2020
Pawan Kumar and Vijay Laxmi Yadav
In this paper, polymeric membranes were prepared by uniformly dispersing the cellulose acetate, polyethylene glycol and polyvinyl pyrrolidone particles in a polyvinyl chloride matrix for resolving the demand for azeotropic mixture separations. The polymeric membranes were characterized using SEM, FTIR and XRD analysis. The results show that the blending of cellulose acetate and plasticizer diethyl phthalate significantly improved the separation performance of the membranes. The selectivity was increased by adding cellulose acetate up to 2% wt and polyethylene glycol 1% wt. Pervaporation setup was used to separate azeotropic mixture using the prepared membrane. The optimum results were obtained for dehydration of alcohol where the composition plasticizer was 0.5% wt. Based on the findings of the research, it was observed that the PVC membrane can be modified with CA and PEG due to their hydrophobic nature. The results show that the synthesized membrane can be used for removal of water from alcohol.
Show more [+] Less [-]Potential of Urban Wetlands for Ecotourism Development- A Case of Deepor Beel, Guwahati
2020
Pratiksha Baruah
Wetlands are amongst the most productive ecosystems of the Earth. The system includes diverse features in terms of components, functions and attributes. Wetland ecosystems are essential to human well-being (Finlayson et al. 2005). A substantial body of evidence demonstrates that wetlands can deliver a great variety of benefits to human society (Ghermandi et al. 2010). Up to 87% of the global wetland resource has been lost since 1700. The planet is losing wetlands three times faster than natural forests. Tourism is one of the significant tools to enhance and support environmental conservation. According to UNWTO, sustainable tourism means putting the principles of sustainable development, set out at the Rio Earth Summit in 1992, into practice in tourism. Deepor Beel is a permanent freshwater lake and the only Ramsar site in Assam which is experiencing adverse human activities; filling of wetlands for habitation purpose, cutting the sides of wetlands, pollution, fishing and killing of migratory birds. Degradation of water quality, sedimentation in the lake surface, deforestation activities in and around the Beel area has increased the importance of conservation and restoration of the Beel. Presently, Deepor Beel is a degrading Beel, facing threats due to urban encroachment and its illegal uses. Therefore, the research questions for this study are- (i) What are the causes and effects of deterioration of the wetland ecosystem? (ii) How to manage the wetland ecosystem through ecotourism development? The study aims to conserve urban wetlands to enhance eco-tourism and have a balanced urban development of Guwahati. To understand the potentiality of eco-tourism in Deepor Beel in Guwahati, the objectives are to understand the importance of urban wetland ecosystem and its present status, to assess the development initiatives in terms of tourism development by government and private sectors in Guwahati, to analyse the socio-economic and governance aspects of the wetland management and tourism in Guwahati and finally to suggest strategies or measures to enhance ecotourism-based wetland development. Primary and secondary data are used in the study through field study and secondary data collection from various organisations. Ecotourism opportunity spectrum is an analysis done to understand the suitability of the wetland for ecotourism development. To understand the anthropogenic impacts of human activity, water quality index, spatial pattern analysis, species diversity index, correlation analysis, carrying capacity analysis, Kuppuswamy’s socio-economic scale, Karl Pearson correlation, vulnerable economic index, WTP-Demand Curve, SWOT analysis and Pralong’s method is used to derive the potentiality of the wetland for ecotourism. Tools like Arc GIS, SPSS, MS Excel, Google Sketch Up and Google Earth have been used for the various analyses of the study. The study would find its application in the field of ecotourism development at the state level which would contribute to the growth of GDP to the nation. The initiatives were taken under ecotourism that incorporates policies and strategies at the organizational level, spatial planning, local community level that would also benefit the local community by generating employment as well as conserving the richness of the biodiversity of the lake. The findings and proposals of the study can be a helpful strategy to develop an appropriate policy for tourism to be beneficial to both the economic benefits of the state and empowerment of the local people.
Show more [+] Less [-]Influence of Expressway Construction on the Ecological Environment and the Corresponding Treatment Measures: A Case Study of Changyu (Changchun-Fuyu Lalin River) Expressway, China
2020
Gao Jiayin, Zhang Mingfei, Hu Zhaoguang and Shan Wei
With astounding advances, China expressway construction has caused inevitable environmental destruction around the construction projects. A series of expressway construction-induced environmental problems is caused by the noise pollution of machinery and equipment in expressway construction, atmospheric pollution caused by fuel consumption, soil contamination caused by abandoned waste materials and gases generated by asphalt mixture during road paving, and increasing traffic volume. In this study, the literature regarding expressway construction-induced environmental pollution was combined by taking Changyu (Changchun-Yulin Lalin River) Expressway as an example. The impacts of expressway construction on the ecological environment were analyzed, and feasible treatment measures were proposed. Results show that the expressway construction in various countries across the globe aggravates the regional ecosystem damage unavoidably to a certain extent; The environmental impacts caused by Changyu Expressway are manifested at five aspects, namely, water environmental pollution, vegetation deterioration, heavy metal pollution, water and soil losses, and induction of geological disasters; The environmental impacts of expressway construction can be mitigated by reasonable route selection, strengthening planning and environmental protection, preventing water and soil losses, reinforcing atmospheric pollution detection, reducing sewage discharge, enhancing vegetation recovery, and relieving the impact on animal habitats. The study results serve as an important reference for identifying the sources of expressway environmental risks and lowering the environmental pollution caused by expressway construction to an acceptable level.
Show more [+] Less [-]Imperious Approach Towards Justifiable Strategic Lake Sediment Regulation
2020
Shekhar Salunke and Balbhim Chavan
Lakes are extremely appreciated for the ecological, aesthetic and recreational values supporting rich biodiversity. As such, their preservation is of supreme importance. A global common problem of sedimentation that eventually seems to be responsible for eutrophication should be immediately attended to, before the degradation begins, since the restoration measures are expensive and may go beyond control. Erosion causes detachment, transportation, and deposition of sediments and is the prime source of contamination where it accumulates in lakes and interrupts the ecological processes and functioning in the lake ecosystem, hence it is important to determine the risk to design management strategies for control. For the present investigation, thematic layers slope identification, NDVI, LULC, lineament density and RUSLE were employed to compute spatially distributed erosion and contaminant sources for the lake Ekrukh of Solapur district of Maharashtra State, India. The research identifies five hazardous erosion zones as; low, moderate, high, very high and severe, through the applied model and dictates formulation and implementation of innovative control strategies preventing soil and water (surface) pollution. The Soil Erosion in Maharashtra, Technical Bulletin, 2001 (Challa et al. 2001) was also referred to for the studies.
Show more [+] Less [-]Operating Performance of China’s Environmental Governance Industry Under the Impact of COVID-19
2020
Zhaohua Leng
With the continuous emergence of environmental problems in recent years, governments of various countries attach great importance to the application of key core technologies such as energy conservation and efficiency, low carbon environmental protection, resource recovery and recycling. The implementation of environmental management concepts is emphasized such as clean production and energy efficiency. As a result, the environmental governance industry has achieved rapid development. However, under the impact of COVID-19, the operation and development of environmental governance industry may be restricted. To explore COVID-19 influence on the operating performance of China’s environmental governance industry, Dongzhu Ecological Environment was selected as the research object, and the operation performance of Dongzhu Ecological Environment was analyzed by using the factor analysis method. The results show that the operating performance of Dongzhu Ecological Environment gets up a lot, with the rise of the whole industry due to the epidemic. Additionally, some management implications were put forward that adopted by the environmental governance industry to better promote the coordinated development of economy, society and environment.
Show more [+] Less [-]Analysis of Soil Characteristics Near the Solid Waste Landfill Site
2020
P. Vijayalakshmi, P. K. Raji, P. Eshanthini, R. Rahul Vijay Bennet and Rajesh Ravi,
In this project, the study of soil characteristics due to the municipal solid waste was carried out in a selected location around the recently closed Municipal Solid Waste (MSW) dumpsite located opposite to Periya Eri in Chromepet, Chennai. Soil samples were collected from the selected location, i.e. 2 sites within 1500m from the dumpsite and another 2 sites beyond 1500m from the dump yard. Total 12 soil samples from 4 sites were collected from a ground depth of 0-30cm, 30-60cm and 60-90cm below the surface. The collected soil samples have been analyzed for pH, moisture, total organic matter, ash content, total organic carbon, specific gravity, conductivity and bulk density and the result were compared with the standards. The study suggested, providing Permeable Reactive Barriers (PRBs) around the solid waste dump site/landfill for reducing the leachate concentration before entering to the soil and thus soil contamination can be minimized to some extent and this technology is cost-effective and eco-friendly since the materials used in the barriers are locally available and low-cost which is sustainable and protect human health, nature and the environment. This study indicated that soil properties did not reach high pollution levels, and therefore posed a low eco-risk potential in surface soil near the landfill.
Show more [+] Less [-]CH4 Emission Flux Model in Rice Growing Season in Cold Region Under Water Saving Irrigation Mode
2020
Lihong Yu , Mengxue Wang
Rice paddies have been identified as major methane (CH4) source induced by human activities. Water management is an important factor affecting CH4 emission during the rice growing season, and the water depth in a rice field directly affects the production, oxidation, and transfer. Field experiments on irrigation management are generally conducted under three modes: control irrigation, intermittent irrigation, and long-term flood irrigation. Static opaque chamber gas chromatographic method was adopted in this work for in situ observations of CH4 emission flux in a field in the rice growing season in a cold region of China. Test data from 2016 was adopted to establish the single factor and interaction types of the CH4 emission flux estimation model for the rice growing season under different water management methods, and the data from 2017 was used for model inspection. The estimation models were based on NO3-N in soil and soil temperature, 10 cm under the soil surface. All models passed the significance test for significance levels of P<0.01. The average forecast error of the model is 13.53-24.78%, and the coefficient of determination Radj2 is between 0.399-0.675. The calculated values of the model are consistent with the measured values. The model established in this research can be used for estimation of CH4 emission in the rice growing season in cold regions of China for different water-saving irrigation modes.
Show more [+] Less [-]A Study on Pullout Test of Root Subjected to Axial Load
2020
Lun Zhang, Zhenyao Xia, Wennian Xu, Xiao Hai, Daxiang Liu,Liming Liu , Bingqin Zhao
Vegetation can enhance the stability of slopes by increasing the shear resistance of the soil. Shear stress applied to the soil matrix is resisted by the pullout strength of the roots via the friction at contact points between the soil and the roots. The effectiveness of root reinforcement depends on interface friction between soil and roots. In this study, tests were carried out on Indigofera amblyantha Craib roots, by measuring resistance as they are pulled out of the soil where the soil has varying dry densities. The results reveal three phases in the relationship between the pullout force and the slippage of the roots, i.e. (1) steep rise, (2) steep fall, and (3) gradual decline. In the first phase, the pullout force is increasing sharply and linearly up to a maximum when the slippage is about 10mm. With continued slippage, the required pullout force decreases significantly and nonlinearly in up and down fluctuations. Eventually, the pullout force reaches zero. For soil with a given dry density, the maximum pullout force increases linearly with increasing root diameter, and the correlation coefficient is greater than 0.9. Further, for a root with a given diameter, the maximum pullout force increases with increasing soil dry density. When the root breaks on pulling, it is called tensile failure; when the root is fully pulled out, it is called friction failure. The mode of failure for all roots is friction failure, for soil with dry densities of 1.35 g/cm3, 1.45 g/cm3, and 1.55 g/cm3. For soil with a dry density of 1.65 g/cm3, and root diameter under 0.716 mm, the observed failure mode is generally tensile; for diameters over 0.716 mm, the failure mode changes to friction; that is, thin roots break, thick roots get pulled out
Show more [+] Less [-]Comparison of Lead Tolerance and Accumulation Characteristics of Fourteen Herbaceous Plants
2020
Xiongfei Cai, Xinjie Yu, Li Lei, Bin Xuan, Ji Wang, Lingyun Zhang and Shijie Zhao
To compare lead (Pb) tolerance and accumulation characteristics, 14 herbaceous plants were treated with different concentrations of lead (0 mg?kg-1, 500 mg?kg-1, 1000 mg?kg-1, 1500 mg?kg-1, 2000 mg?kg-1) through an indoor pot experiment. Results indicated that the shoot dry weights (DWs), tolerance index (TI) and root tolerance index (RTI) of 14 herbaceous plants decreased with the increase of lead concentration. After comprehensive evaluation, Campsis grandiflora, Polygonum lapathifolium, Lolium perenne, and Poa annua were confirmed as tolerant plants to be cultivated in lead-zinc mining area. Moreover, shoots of the Rudbeckia hirta could effectively absorb the lead (I I) with the bioconcentration factor (BCF) of 2.29. The translocation factor (TF) of 6 herbaceous plants were larger than 1.0. They are: Polygonum lapathifolium (3.04) > Medicago sativa (2.49) > Rudbeckia hirta (1.72) > Talinum paniculatum (1.44) > Capsicum annuum cv. 276 (1.36) > Trifolium repens (1.21. Finally, after integration the BCF, TF and repair potential indices, we found that Rudbeckia hirta had a good restoration potential and its lead cumulation in the shoot was the highest (2.576 mg per plant) when the concentration was up to 1000 mg?kg-1. Therefore, Rudbeckia hirta could be identified as a pioneer species of Pbhyperaccumulator.
Show more [+] Less [-]The Effect of Ejectors on Reduction of Indoor Air Pollution in the Welding Room
2020
Sattar Yunus, Makmur Saini, Rizal Sultan, Rusdi Nur and Ibrahim
In this study, the ejector installation has been designed and processed according to the plan and further investigated the effect of the ejector’s performance on reducing air pollutants in a welding chamber. This is done after gas and dust particles appear during the welding process. The measurement of air pollutants was carried out in two conditions. The first condition during the welding process was without using the ejector and the second condition is when the welding process continues and the ejector runs simultaneously. The measurements were made for carbon monoxide (CO) gas, nitrogen monoxide (NO) gas and total suspended particles. The ambient gas sampler was used in measuring CO and NO gases, while the Staflex air sampler measures dust particles. The results show that when the ejector is run or in the second condition, carbon monoxide and nitrogen monoxide and total dust particles are lower in concentration compared to the situation when the ejector is not running.
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