Уточнить поиск
Результаты 31-40 из 3,208
Consumer attitudes and perceptions on electronic waste: An assessment Полный текст
2015
Saritha, Vara | Sunil Kumar, KA | Srikanth Vuppala, NV
The electronics industry is one of fastest growing manufacturing industries in India. However, the increase in the sales of electronic goods and their rapid obsolescence has resulted in the large-scale generation of electronic waste, popularly known as e-waste. E-waste has become a matter of concern due to the presence of toxic and hazardous substances present in electronic goods which, if not properly managed, can have adverse effects on the environment and human health. In India, the e-waste market remains largely unorganized, with companies being neither registered nor authorized and typically operating on an informal basis. In many instances, e-waste is treated as municipal waste, because India does not have dedicated legislation for the management of e-waste. It is therefore necessary to review the public health risks and strategies in a bid to addressthis growing hazard. There is the strong need for adopting sustainability practices in order to tackle the growing threat of e-waste. In the present work, we attempt to identify the various sources and reasons for e-waste generation, in addition to understanding the perception of the public towards e-waste management. This study aims to induce an awareness of sustainability practices and sustainability issues in the management of E-waste, especially waste related to personal computers (PCs) and mobile phones. From the results of the study, we concluded that the majority (90%) of the public is ignorant about e-waste and its issues; hence, there is a strong requirement for spreading awareness about the growing hazard of E-waste.
Показать больше [+] Меньше [-]Sources, demand and problems of domestic water in Nassarawa Eggon Town, Nigeria Полный текст
2015
Ezekiel, Ayiwulu | Dominic, Alexander
This paper examines the relationship between domestic water sources, demand and associated problems in the context of a rapidly increasing household population in Nassarawa Eggon town, Nasarawa State, Nigeria. The data for this research were generated using a questionnaire survey of systematically selected households, and analysed using descriptive statistics in the form of frequencies and percentages, and are presented as tables and graphs. The study revealed that the major sources of water in the area are hand-dug wells and streams, with no pipe-borne water. This has greatly affected the inhabitants of the locality, resulting in cases of water-related diseases. Consequently, due to the recent inter-communal and ethnic crisis in some parts of the local government area and the state, which led to massive immigration of people into Nassarawa Eggon, pressure on the available sources of domestic water has intensified, resulting in insufficiency in meeting domestic water demand. Against this backdrop, the paper seeks to examine in detail the various sources of domestic water and the problems associated with accessing it.
Показать больше [+] Меньше [-]Palm kernel fruit fiber reinforced gypsum-cement based wall panels: It’s physical and mechanical characteristics Полный текст
2015
Abuh, Noah | Umoh, Akaninyene
Agricultural waste fibers have been found to be suitable as reinforcement in cement-based composites, but studies on oil palm fiber as reinforcement in gypsum-cement wall panels are scarce. A mixture of two equal weights of gypsum and cement, with water-binder ratios of 0.45 and 0.55 were prepared. In each mix a varying percentage of fiber contents of 2%, 3% and 4% by weight of the binders were added. The properties of the wall panels were determined from cast specimen sizes of 100x 100 x 40 mm for density, moisture content and water absorption; 160 x 40 x 40mm for compressive strength, and 650 x 100 x 25 mm for bending strength. The specimens were cured in water and tested at ages of 3, 7, 14, 21, and 28 days. The results of density of the wall panels were within the range of 1634–1742 kg/m3, while the moisture content range of 3.30–8.45%, and the water absorption varies from 5 to 12%. The compressive strengths were found within the range of 1.92–5.20N/mm2 and, generally, decreases with the increasing percentage of fiber contents, but increased with curing age. The bending strength falls within the range of 2.04–4.13 N/mm2that increases with curing age and slightly increased with fiber content. It is concluded that oil palm fiber reinforced gypsum-cement wall panels are suitable as wall element.
Показать больше [+] Меньше [-]Laser land levelling as a strategy for environmental management: the case of Iran Полный текст
2015
Tohidyan Far, Somayeh | Rezaei-Moghaddam, Kurosh
The impact assessment method seeks to bring about a more ecologically, socio-culturally and economically sustainable and equitable environment. Determining the main factors affecting the attitudes of stakeholders is crucial for understanding the impacts of development plans. This approach helps planners and decision makers to identify the values and traits of stakeholders and accelerate the diffusion of innovations through designing proper incentives and removing available obstacles. The purpose of this study is to examine factors affecting laser land levelling project impacts in Fars Province, Iran. The sample included 285 farmers who were selected using multi-stage random sampling. The validity and reliability of the questionnaire were measured and revisions were made to improve measurement scales. The results of structural equation modelling indicated that reduction in water consumption was the most important variable which affected the recognition of impacts among laser land levelling adopters. Furthermore, laser land levelling impacts as dependent variables were influenced by the direct effect of the duration of adoption, attitude towards water and soil conservation, need perception and attitude toward prior projects. Based on the results, practical recommendations have been presented.
Показать больше [+] Меньше [-]Assessing environmental contamination of River Ganga using correlation and multivariate analysis Полный текст
2015
Bhutiani, Rakesh | Khanna, D.R. | Tyagi, Bharti | Tyagi, Prashant | Kulkarni, Dipali
The aim of this study was to assess the environmental impact of socio-cultural practices on the water quality of River Ganga at the foothills of the Garhwal Himalayas in Uttarakhand State, India. The physico-chemical parameters that contributed to the temporal variation and pollution in the river were identified in this study. Principal component analysis (PCA) and Cluster analysis (CA) were used in the identification of anthropogenic factors (industrial, urban sewage, agricultural, land use and mining activities) and natural factors (soil erosion, weathering). The results of this study show that total coliform, fecal coliform, nitrate, sodium, phosphate, sulphate, TDS (Total dissolved solids), temperature, BOD (Biochemical oxygen demand), calcium and chloride are parameters significantly contributing to pollution load.
Показать больше [+] Меньше [-]Vulnerability assessment of surface water quality with an innovative integrated multi-parameter water quality index (IMWQI) Полный текст
2015
Sikder, Md. | Tanaka, Shunitz | Saito, Takeshi | Hosokawa, Toshiyuki | Gumiri, Sulmin | Ardianor, Ardianor | Uddin, Md. | Tareq, Shafi | Shammi, Mashura | Kamal, AK | Kurasaki, Masaaki
The development of a surface water evaluation index is a critical factor in the assessment, restoration and protection of stream water quality. Quantifying water pollution in specific grade using dominant parameters is important, as this can explain the current state of water pollution with accuracy. As a result, an integrated multi-parameter water quality index has been developed. It is based on the 10 most prevailing parameters (pH, conductivity, nitrate ions, phosphate ions, Escherichia coli number, cadmium, chromium, lead, copper and manganese) with a scale of 1 to 4, wherein the grades are classified into 1: good; 1.1-1.5: slightly polluted; 1.6-2.0: moderately polluted; 2.1-2.9: heavily polluted and 3.0-4.0: gravely polluted. The measuring stick used was according to the 2011 background values of the World Health Organization (WHO) in which a value of 0.1 was attributed for each, so that the final grade can be calculated. Water quality data were successfully fitted in an integrated multi-parameter water quality index to measure the river water level of pollution, and effectively represented every water bodies. This innovative index is able to quantify pollution with respect to seasons, geography and geomorphology of the respective rivers. Although operative, this index still lacks scientific integrity and as such, more synoptic experiments in the rivers of developing countries are recommended to attain a pragmatic feature.
Показать больше [+] Меньше [-]Potential of Lemna minor in Ni and Cr removal from aqueous solution Полный текст
2015
Goswami, Chandrima | Majumder, Arunabha
Duckweeds are of special interest, as they are naturally growing weeds that have the capacity to tolerate and remove toxic pollutants, including heavy metals from the environment. Studies have revealed that duckweed (Lemna minor) can tolerate and remove heavy metals from aqueous solutions. In the present study, the efficiency of L. minor in the removal of Ni and Cr individually from aqueous solutions was investigated at concentrations of 3.05, 3.98 and 4.9 mg/L for Ni and 1.91, 2.98, and 4.2 mg/L for Cr. Experiments were run for 22 days, after which the metal content in the plant was estimated by atomic absorption spectrophotometer (AAS). The duckweed showed higher percentage of Ni removal than Cr. Specific Growth Rate (SGR) was found to be reduced at high concentrations of both Ni and Cr. Statistical analysis suggested that the growth of the plant was affected by the toxic effect of both Ni and Cr. Bioaccumulation of Ni was higher than Cr in L. minor. The mechanism of removal of both Ni and Cr followed second order kinetics. It is suggested that these duckweeds can remove Ni and Cr from aqueous solution and can also accumulate the same in considerable concentrations, at low initial metal concentrations.
Показать больше [+] Меньше [-]Cost Appraisal of Municipal Solid Waste Transfer to Disposal Site Using Visual Basic Program Полный текст
2015
Olukanni, David | Iroko, Samuel | Aremu, Adeniyi
Collection of Municipal Solid Waste (MSW) accounts for a significant proportion of most municipal budgets, and has drawn some degree of researchers‟ interest. This study was conducted in Ota, Southwest Nigeria, to explore the use of Visual basic program as an innovative tool to select the most economic haulage system among three systems found in literature (conventional-, modified- and Stationary- hauled system) for collection and transfer of MSW to disposal sites. Factors that affect the costs of collection and transportation of waste such as: vehicle cost, total time spent on waste collection, and gross travel cost, were considered in the analysis. The result of the study shows that the stationary hauled method of waste collection is the optimal and economical method of collection. This method recorded a 56% and 43% reduction in total cost of daily travel per waste collection, as compared to the conventional and the modified systems, respectively. The application of visual basic program proffers implementable solutions to reduce the cost of MSW transportation to disposal sites. This would reduce travel time and costs of vehicle fueling, and increase the prompt collection of waste which would in turn facilitate the development of an aesthetically balanced and environmentally friendly municipality that would perhaps boost economic development.
Показать больше [+] Меньше [-]Positive effects of Vitamin C in arsenic trioxide and sodium fluoride induced genotoxicity and oxidative stress in mice in vivo Полный текст
2015
Roy, Prasenjit | Mukherjee, Anita | Giri, Sarbani
The aim of the present study was to evaluate Vitamin C (VC) as a potent natural antioxidant to mitigate the genotoxic effects of Arsenic trioxide and sodium fluoride in Swiss albino mice in vivo. The study was divided into eight groups consisting of control treated with normal saline (Group I), Group II, III, IV, V, VI, VII and the VC group with only Vitamin C (500 mg/kgbw). Arsenic trioxide (4 mg/kgbw) and Sodium fluoride (8 mg/kgbw) were administered singly, as well as in combination to swiss albino mice, with and without VC. In this study, the genotoxic effect of arsenic (As) and fluoride (F) in mice using comet, chromosomal aberration and lipid peroxidation assay was investigated. The results revealed that VC efficiently ameliorates the genotoxic effect of As and F by increasing the frequency of chromosomal aberrations and primary DNA damage along with increased malondialdehyde (MDA) level. In conclusion, VC mitigates the genotoxic effects of the two well-known water contaminants (As and F) effectively and efficiently at the given concentration in vivo.
Показать больше [+] Меньше [-]Micro and Small Enterprises in Solid Waste Management: Experience of Selected Cities and Towns in Ethiopia: A Review Полный текст
2015
Damtew, Yohannes Tefera | Desta, Biniyam Negussie
Municipalities in developing countries spend the highest proportion of their annual budget on unsatisfactory solid waste management service. Until recently, solid waste management services in Ethiopia were mainly the responsibilities of municipalities, which culminated in inadequate service provision. Thus, the integration of Micro and Small Enterprises (MSEs) by the government has recently being considered as an option. Participation of MSEs in SWM started in 2003/04 in Addis Ababa, the capital city of Ethiopia and expanded to other cities following the proclamation of a National Solid Waste program in 2007. This review is aimed at identifying the role of MSEs in solid waste management in selected cities, including the opportunities and challenges for future directions. Limited resources and lack of support, perception and awareness of the community, inadequate training, unorganized fee collection strategy and limited revenue were among the challenges identified. The benefits and potential opportunities include organized and quality service delivery, environmental protection and safety, job opportunity, willingness to pay and social equity. In conclusion, the findings in this review show the importance of MSEs in solving solid waste management problems. However, the challenges need due considerations and appropriate interventions such as legalization of the informal sector, clear working guidelines and regulations, close support and monitoring, and transparent system in general.
Показать больше [+] Меньше [-]