This study deals with generation, composition, collection, transportation, and disposal, as well as the present cost of the waste management on the basis of 60% collection of the total waste and the cost of proposed improved system of management on the basis of 100% waste collection using the IWM-2 LCI model. A GIS map of Data Ganj Bakhsh Town (DGBT) of Lahore City District showing communal storage facilities is also provided. DGBT has a population of 1,624,169 living in 232,024 dwellings. The total waste generated per year is 500,000 tons, or 0.84/kg/cap/day. Presently 60% of the MSW is collected and disposed in open dumps, while 40% is not collected and lies along roadsides, streets railway lines, depressions, vacant plots, drains, storm drains and open sewers. In DGBT, 129 containers of 5-m3 capacity, 120 containers of 10-m3 capacity and 380 skips of 2.5-m3 capacity are placed for waste collection. The overall collection and disposal cost of the MSW of DGBT is $3,177,900/yr, which is $10.29/ton. Modeling was conducted using the IWM-2 model for improved collection and disposal on the basis of 100% service, compared to the current 60% service. The modelled cost is $8.3/per ton, which is 20% less than the present cost, but the overall cost of 100% collection and disposal increases to $4,155,737/yr. 相似文献
In this study, a biodegradable composite consisting of a degradable continuous cellulosic fiber and a degradable polymer matrix—poly(3-hydroxybutyrate)-co-poly(3-hydroxyvalerate
(PHB/V with 19% HV)—was developed. The composite was processed by impregnating the cellulosic fibers on-line withPHB/V powder in a fluidization chamber. The impregnated roving was then filament wound on a plate and hot-pressed. The resulting
unidirectional composite plates were mechanically tested and optically characterized by SEM. The fiber content was 9.9 ±0.9
vol% by volumetric determination. The fiber content predicted by the rule of mixture for unidirectional composites was 13.8
±1.4 vol%. Optical characterization showed that the fiber distribution was homogeneous and a satisfactory wetting of the fibers
by the matrix was achieved. Using a blower to remove excess matrix powder during processing increased the fiber content to
26.5 ±3.3 vol % (volumetric) or 30.0 ±0.4 vol% (rule of mixture). The tensile strength of the composite parallel to the fiber
direction was 128 ±12 MPa (10 vol% fiber) up to 278 ±48 MPa (26.5 vol% fiber), compared to 20 MPa for the PHB/V matrix. The
Young’s modulus was 5.8 ±0.5 GPa (10 vol% fiber) and reached 11.4 ±0.14 GPa (26.5 vol% fiber), versus 1 GPa for the matrix. 相似文献
Vehicular traffic is one of the main sources of antimony in highly populated urban areas like Buenos Aires where an overall traffic density of 1 500 000 vehicles per day (corresponding to 7500 vehicles km(-2)) is estimated. In this context, a study was undertaken to ascertain the levels of Sb and other traffic-related elements (TRE) in the atmosphere of this city. To this end, sixty-seven samples of PM-10 particulate matter were collected during eight days in nine representative sampling sites located downtown Buenos Aires and spread over an area of about 30 km2. The collection of particulate matter was performed on ash-free glass-fibre filters using high volume samplers with PM-10 sampling heads. A combination of aqua regia and perchloric acid was used for leaching metals from filters. The resulting solutions were evaporated and then diluted with 0.1 mol l(-1) HCl. Antimony was determined by inductively coupled plasma-quadrupole mass spectrometry (ICP-QMS) at ng g(-1) levels. Concentrations of Sb varied from 12.9 +/- 0.9 to 375 +/- 23 microg g(-1)(equivalent to 0.87 +/- 0.06 to 15.3 +/- 0.8 ng m(-3)). Statistical analysis was performed on the data set including the measured PM-10 mass and Sb concentrations for the monitored period. Correlations of Sb with other TRE namely, Cu and Mo were also assessed. The highest concentrations of Sb were detected at two sites (Hospital Alemán and Casa Rapallini) located in streets with traffic consisting mostly of passenger cars and showing a "stop-and-go" pattern in peak hours. Antimony levels in the Buenos Aires PM-10 are by far below the level of 0.5 mg m(-3)(for an 8 hour workday, 40 hour work week) set by the US Occupational Safety and Health Administration (OSHA) for occupational exposure. However, monitoring of Sb and other TRE should be carried out in a systematic fashion to detect the possibility of increases in from the present levels. 相似文献
Two test methods are presented to assess the cytotoxicity of chemicals. On one hand the protozoonTetrahymena pyriformis and on the other the bacteriumPseudomonas aeruginosa is cultured in defined media containing the test chemicals. Test parameter is the quantity of living cells surviving exposure. The conversion of the tetrazolium salt MTT into formazan is equivalent to cell viability. A mixture of detergent and isopropanol is used to dissolve the blue formazan which is not soluble in water, prior to photometric measurement. For cetyltrimethylammonium bromide, benzyldimethyldodecylammonium chloride, dodecylbenzenesulfonic acid sodium salt, potassium dichromate, 4-toluenesulfonic acid sodium salt, and 4-nitrophenol the EC50-values (mol/l) in theTetrahymena pyriformis- (Pseudomonas aeruginosa) test system were: 10?5,81 (10?5,08); 10?4,68) (10?3,80; 10?4,50 (10?4,14); 10?3,97 (10?5,11); 10?2,71 (10?2,50) and 10?4,00 (10?3,64). — With the assays described here it is possible to measure a large number of samples by quick and simple means. 相似文献
This article reports a study of the economic viability of a separate household waste collection project, and considers its social and environmental benefits. The study was developed from the database obtained through the pilot project on separate collections in João Pessoa, the capital of Paraíba, in the northeast region of Brazil. The pilot project had been supported by the local municipal council since September 2000. The methodology applied to this study of economic viability is based on the economic quantification of the benefits and costs involved in the process of a separate collection of household waste. The benefits to the environment, owing to the reduction of the final disposal of household waste, were also evaluated. The results of this research are encouraging for the benefit cost relation (B/C) of both the quantified economic components and the environmental aspects. The values found for the relation B/C ranged from 1.27 to 1.77 depending on the economic quantification of the direct and indirect benefits to the components involved in the project, i.e., the waste collectors, the municipal council, the sellers of recycled material, and the recycling industry. 相似文献
This paper investigates the dimensions of sustainable behavior, with a particular focus on the aspects of self-care, caring for others, and caring for the environment. Its aim was to test the assumption that sustainable behavior not only encompasses pro-social and pro-environmental actions, as the current research acknowledges, but also behaviors that are directed toward self-preservation and care. A subscale of self-care specifically developed for this research was added to a series of previously validated instruments assessing altruistic, equitable, pro-ecological, and frugal behaviors to examine the personal, social, and physical environmental aspects of sustainable behavior. Responses from a sample of 290 participants confirmed the three-dimensional structure of sustainable behavior. Results suggest sustainability, understood as a chain of interdependences between the individual, society, and nature, begins with self-care and continues with caring for others, and with caring for the biosphere, which, in turn, affords for a more sustainable environment for the individual.
The Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) onboard the European Envisat spacecraft performs continuous spectral observations of reflected, scattered and transmitted sunlight in various observation geometries. A unique feature of SCIAMACHY is the capability of probing the atmosphere in three different observation geometries:The nadir, limb, and occultation measurement modes. In nadir mode, column densities of trace gases are retrieved with a spatial resolution of typically 30× 60 km using the Differential Optical Absorption Spectroscopy (DOAS) technique (Platt and Perner, 1983). Alternating with the nadir measurement, vertical profiles of absorber concentration in the stratosphere are derived in limb and occultation. In this paper we present an overview over some applications of SCIAMACHY data in space-based monitoring of atmospheric pollution. The DOAS algorithms for the retrieval of total column amounts from nadir spectra are briefly described and case studies of pollution events are presented. We also illustrate the technique used to derive stratospheric concentration profiles from limb observations and show comparisons with other remote sensing systems. Special emphasis will be given to techniques, which take advantage of SCIAMACHY's different viewing geometries. In particular, we will discuss the potential and limits of strategies to infer tropospheric abundances of O3and NO2. 相似文献
The Arctic is nutrient limited, particularly by nitrogen, and is impacted by anthropogenic global warming which occurs approximately twice as fast compared to the global average. Arctic warming intensifies thawing of permafrost-affected soils releasing their large organic nitrogen reservoir. This organic nitrogen reaches hydrological systems, is remineralized to reactive inorganic nitrogen, and is transported to the Arctic Ocean via large rivers. We estimate the load of nitrogen supplied from terrestrial sources into the Arctic Ocean by sampling in the Lena River and its Delta. We took water samples along one of the major deltaic channels in winter and summer in 2019 and sampling station in the central delta over a one-year cycle. Additionally, we investigate the potential release of reactive nitrogen, including nitrous oxide from soils in the Delta. We found that the Lena transported nitrogen as dissolved organic nitrogen to the coastal Arctic Ocean and that eroded soils are sources of reactive inorganic nitrogen such as ammonium and nitrate. The Lena and the Deltaic region apparently are considerable sources of nitrogen to nearshore coastal zone. The potential higher availability of inorganic nitrogen might be a source to enhance nitrous oxide emissions from terrestrial and aquatic sources to the atmosphere.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01665-0. 相似文献