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21.
This paper examines the relationship between community preparedness and response to natural disaster and their level and pattern of community development. This is done by investigating preparation and response to the 1997 Red River Flood by three rural communities in Manitoba, Canada. The communities were selected because of their different ethnic mix and associated level and pattern of community development. The hypothesis was supported that the level and pattern of community development affect community capacity to respond to flooding. Communities characterised by higher levels of physical, human and social capital were better prepared and more effective responders to the flood. However, where the pattern of community development was characterised by high levels of social capital, decision-making processes were complicated.  相似文献   
22.
Bricks produced from sewage sludge in different compositions were investigated. Results of the tests indicated that the sludge proportion is a key factor in determining the brick quality. Increasing the sludge content results in a decrease in brick shrinkage, bulk density, and compressive strength. Brick weight loss on ignition was mainly due to the contribution of the contained organic matter from the sludge being burnt off during the firing process, as well as inorganic substances found in both clay and sludge. The physical, mechanical, and chemical properties of the bricks that were supplemented with various proportions of dried sludge from 10 to 40wt% and generally complied with the General Specification for Brick as per the Malaysian Standard MS 7.6:1972, which dictates the requirements for clay bricks used in walling in general. A standard leaching test method also showed that the leaching of metals from the bricks is very low.  相似文献   
23.
A series of formulations were prepared with different percentages of oligomer, epoxy diacrylate (EA-1020 ), monomer, 1,6 Hexane diol diacrylate,(HDDA) and different percentages of filler (Magnesium tri-silicate, Mg2Si3O8). Irgacure 369 [2-Benzyl-2-dimethyl-amine-1 (4-morpholinophenyl) butanone-1] was used in the formulations as photoinitiator. Ultraviolet (UV) cured thin polymer films were prepared from these formulating solutions on clean glass plates. Pendulum hardness (PH), gel content and macro scratch hardness (MSH) of the UV cured films were studied. One percent Mg2Si3O8 containing formulation showed the premium properties. The substrates (plain board) were coated by these formulating solutions and cured under the same UV lamp at different intensities of radiation. Various properties of the coated surface such as PH, gloss, adhesion, abrasion and MSH were investigated. The base coat containing 1% Mg2Si3O8 and top coat containing 48% HDDA produced the best performance among all the formulations inspected. The degradable properties in different weathering conditions on PH, gloss, adhesion, abrasion and MSH were measured. The surface cured with the optimized formulation (E) again yielded the minimum loss of the properties.  相似文献   
24.
The persistence of pesticides in soils has both economic and environmental significance and is often used as a key parameter in pesticide risk assessment. Persistence of acetochlor [2'-ethyl-6'-methyl-N-(ethoxymethyl)-2-chloroacetylanilide] in two New Zealand field soils was measured over two years and the data were used to identify models that adequately describe acetochlor persistence in the field. Acetochlor was sprayed onto six fallow plots (3 x 9 m each) at each site at the recommended rate (2.5 kg a.i. ha(-1)) and at twice that rate. Acetochlor concentrations were measured in soil cores. Simple first-order kinetics (Model 1) adequately described acetochlor persistence in Hamilton clay loam soil (Humic Hapludull, Illuvial Spadic) at the high application rate, but overestimated it at the low application rate. A quadratic model (Model 2), a first-order double-exponential model (Model 3), a first-order biphasic model (Model 4), or a two-compartment model (Model 5) better described acetochlor persistence at the low application rate. The time for 50% (DT50) and 90% (DT90) of initial acetochlor loss was approximately 9 and 56 d, and 18 and 63 d at low and high application rates, respectively. The more complex Models 2 through 5 also better described the biphasic dissipation of acetochlor in Horotiu sandy loam soil (Typic Orthic Allophanic) than Model 1, with Model 1 significantly underestimating acetochlor concentrations on the day of application at both application rates. The DT50 and DT90 values were 5 and 29 d and 7 and 31 d at low and high application rates, respectively. Overall, application rate significantly affected the DT50 and DT90 values in the Hamilton soil, but not in the Horotiu soil. Faster acetochlor loss in the Horotiu soil possibly resulted from the higher soil organic carbon content that retained more acetochlor near the soil surface where higher temperature and photolysis accelerated the loss.  相似文献   
25.
In this work, soil-to-plant transfer factors of radiocaesium are predicted based on soil properties such as pH, organic matter content, exchangeable K+ and clay content valid for the tropical environments in Bangladesh, China and Japan, and using a previously published model. Due to insufficient data of soil properties in the selected regions, the average values of pH, organic matter content, exchangeable K+ and clay content were taken as the input model parameters within the ranges given for Asia. Nevertheless, a complete set of soil properties of Japanese soils was used to compare the measured and calculated TF values of radiocaesium for radish. The calculated TF values for radiocaesium are comparable with the measured values especially for leafy parts of a plant. However, calculated values for rice, an important crop in Asia are found to overestimate the measured values due to an overestimate of calculated CECs in soils in the selected regions. The empirical parameters used in the model need to be re-evaluated for the specific part of a plant and/or for a variety of different plants. Alternatively, a general conversion factor for each part of a plant and/or for a variety of different plants for a specific region is suggested for tropical environments.  相似文献   
26.
Farmers' perception of the environmental impacts of modern agricultural technology diffusion and factors determining such awareness were examined using survey data from 21 villages in three agro-ecological regions of Bangladesh. Results reveal that farmers are well aware of the adverse environmental impacts of modern agricultural technology, although their awareness remains confined within visible impacts such as soil fertility, fish catches, and health effects. Their perception of intangible impacts such as, toxicity in water and soils is weak. Level and duration of modern agricultural technology adoption directly influence awareness of its adverse effects. Education and extension contacts also play an important role in raising awareness. Awareness is higher among farmers in developed regions, fertile locations and those with access to off-farm income sources. Promotion of education and strengthening extension services will boost farmers' environmental awareness. Infrastructure development and measures to replenish depleting soil fertility will also play a positive role in raising awareness.  相似文献   
27.
This paper presents a forecasting study of municipal solid waste generation (MSWG) rate and potential of its recyclable components in Kuala Lumpur (KL), the capital city of Malaysia. The generation rates and composition of solid wastes of various classes such as street cleansing, landscape and garden, industrial and constructional, institutional, residential and commercial are analyzed. The past and present trends are studied and extrapolated for the coming years using Microsoft office 2003 Excel spreadsheet assuming a linear behavior. The study shows that increased solid waste generation of KL is alarming. For instance, the amount of daily residential SWG is found to be about 1.62 kg/capita; with the national average at 0.8–0.9 kg/capita and is expected to be increasing linearly, reaching to 2.23 kg/capita by 2024. This figure seems reasonable for an urban developing area like KL city. It is also found that, food (organic) waste is the major recyclable component followed by mix paper and mix plastics. Along with estimated population growth and their business activities, it has been observed that the city is still lacking in terms of efficient waste treatment technology, sufficient fund, public awareness, maintaining the established norms of industrial waste treatment etc. Hence it is recommended that the concerned authority (DBKL) shall view this issue seriously.  相似文献   
28.
DDT—1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane—is a pesticide that has been widely used to control insects in agriculture. TCP—2,4,6-trichlorophenol—has been used in pesticide formulations as a preservative, disinfectant and antiseptic. Detoxification of DDT and TCP is very difficult due to their stable chemical structure. Here, a mixture of NaBH4 and Devarda alloy was applied for the first time to detoxify DDT and TCP. Results show 94 % dechlorination of DDT at 100 °C and 97 % dechlorination of TCP at 80 °C. The presence of diphenyl ethane suggests the complete dechlorination of DDT. The formation of benzene suggests a strong reduction. The method is efficient, cost-effective and may be applied at the industrial-level.  相似文献   
29.
Abstract

Bangladesh is on target for achieving the Millennium Development Goal 4 relating to infant and under-five mortality because of very rapid reduction in mortality in recent years. But this rate of reduction may be difficult to sustain and may hamper the achievement of Millennium Development Goal 4. Therefore, the main objective of this paper is to discuss and compare the different covariates of infant and under-five mortality in the context of overall country, urban and rural levels of Bangladesh using discriminant analysis. For this, the data are taken from Bangladesh Demographic and Health Survey, 2004. In discriminant analysis, the stepwise procedure has been picked up and only the significant variables are ranked according to the rank of Wilk’s Lambda values. The canonical discriminant function coefficients (unstandardized and standardized) for the predictor variables have also been calculated. Both the results show that breastfeeding is the most important variable in discriminating the two groups of mothers, i.e., mothers experiencing to infant mortality or not and mothers experiencing to under-five mortality or not. The related results of discriminant function also indicate that the discriminant function is statistically significant and discriminates well. Therefore, improvements in the health system are essential for promoting the breastfeeding practices (both inclusive and exclusive), which may be the effective strategies to reach families and communities with targeted messages and information.  相似文献   
30.
Radon exhalation from building materials for decorative use   总被引:2,自引:0,他引:2  
Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m−2 d−1. Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m−2 d−1 for slate tiles and 42 Bq m−2 d−1 for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m−2 d−1, it would contribute only 18 Bq m−3 to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.  相似文献   
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