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81.
Long-term measurements (2004–2011) of PM10 (particulate matter with an aerodynamic diameter <10 μm) and trace gases (carbon monoxide [CO], ozone [O3], nitrogen oxide [NO], oxides of nitrogen [NOx], nitrogen dioxide [NO2], sulfur dioxide [SO2], methane [CH4], nonmethane hydrocarbon [NMHC]) have been conducted to study the effect of physicochemical factors on the PM10 concentration. In addition, this study includes source apportionment of PM10 in Kuala Lumpur urban environment. An advanced principal component analysis (PCA) technique coupled with absolute principal component scores (APCS) and multiple linear regression (MLR) has been applied. The average annual concentration of PM10 for 8 yr is 51.3 ± 25.8 μg m?3, which exceeds the Recommended Malaysian Air Quality Guideline (RMAQG) and international guideline values. Detail analysis shows the dependency of PM10 on the linear changes of the motor vehicles in use and the amount of biomass burning, particularly from Sumatra, Indonesia, during southwesterly monsoon. The main sources of PM10 identified by PCA-APCS-MLR are traffic combustion (28%), ozone coupled with meteorological factors (20%), and windblown particles (1%). However, the apportionment procedure left 28.0 μg m?3, that is, 51% of PM10 undetermined.

Implications: Air quality is always a top concern around the globe. Especially in the South Asian regions, measures are not yet sufficient; as revealed in our studies, the concentrations of particulate matters exceed the tolerable limits. Long-term data analysis and characterization of particular matters and their sources will aid the policy makers and the concerned authority to adapt measures and policies according to the circumstances. Additionally, similar intensive studies will give insight about future implications of air quality management.  相似文献   
82.
Usage of plastics has been ever increasing and now poses a tremendous threat to the environment. Millions of tons of plastics are produced annually worldwide, and the waste products have become a common feature at overflowing bins and landfills. The process of converting waste plastic into value-added fuels finds a feasible solution for recycling of plastics. Thus, two universal problems such as problems of waste plastic management and problems of fuel shortage are being tackled simultaneously. Converting waste plastics into fuel holds great promise for both the environmental and economic scenarios. In order to carry out the study on plastic wastes, the pyrolysis process was used. Pyrolysis runs without oxygen and in high temperature of about 250–300 °C. The fuel obtained from plastics is blended with B20 algae oil, which is a biodiesel obtained from microalgae. For conducting the various experiments, a 10-HP single-cylinder four-stroke direct-injection water-cooled diesel engine is employed. The engine is made to run at 1500 rpm and the load is varied gradually from 0 to 100 %. The performance, emission and combustion characteristics are observed. The BTE was observed to be higher with respect to diesel for plastic-biodiesel blend and biodiesel blend by 15.7 and 12.9 %, respectively, at full load. For plastic-biodiesel blend, the emission of UBHC and CO decreases with a slight increase in NO x as compared to diesel. It reveals that fuel properties are comparable with petroleum products. Also, the process of converting plastic waste to fuel has now turned the problems into an opportunity to make wealth from waste.  相似文献   
83.
The benthic macrofauna and physical features of 10 sandy beaches along the coast of Oman were surveyed quantitatively. This is a mesotidal regime mostly subject to low to moderate wave energy but more exposed in the south. Five northern beaches are tide-dominated, with low wave energy, and their profiles consist of a berm, a steep, swash-dominated upper shore and a broad tide-dominated terrace from mid-shore downwards. They are composed of moderately sorted fine to medium sands. Southern beaches experience greater wave energy, particularly during the summer southwest monsoon, and exhibit smoother, concave profiles with fine, fairly well sorted carbonate sand. 58 species and species groups were recorded, with crustanceans, polychaetes and molluscs dominant. In general species richness was high, at least 19–25 species per beach, but dry biomass moderate to low at 26–90g/m shoreline, with one high value of 450g/m. Total abundance was moderate at 3–73×103 organisms/m of beach. Some zonation was evident with ocypodid crabs andTylos in the supralittoral, cirolanid isopods on the upper shore and a variety of species on the lower shore. The coast of Oman appears to constitute a single zoogeographic region, but with some regional differentiation between north and south due to varying physical conditions. Thus, OmanÕs beaches are characterized by tide-dominated morphodynamics and exceptionally high species richness.  相似文献   
84.
Although high concentrations of trace organic pollutants were recorded along the Egyptian Mediterranean Coast and its corresponding coastal wetlands, no published data are available for the levels of phenolic compounds. Thus, this work aimed to investigate the levels of phenolic compounds in sediments of a heavily polluted coastal wetland (Lake Maryut, Egypt). For that purpose, a method was optimized for the extraction and detection of chlorophenols, methylphenols, and nitrophenols in sediments using GC-MS. Sediments were extracted with 0.1 M NaOH/methanol by sonication. Cleanup of sediment extracts using liquid–liquid extraction and SPE was found important to remove most of the interfering co-extracts. The proposed analytical methodology was validated by analysis of matrix spikes. Detection limits were 0.063–0.694 μg/kg dw for sediments. Good recoveries (70–110%) and precision values (RSD?<?20%) were obtained from the fortification experiments at the parts per billion level in sediments. The method was applied to investigate the level of contamination with phenols in 19 sediment samples from Lake Maryut. Results revealed that higher concentrations were observed in the main basin (MB) of Lake Maryut affected by the discharge of effluents from a primary wastewater treatment plant, direct discharge of industrial effluents, domestic wastes, and agricultural effluents from Qalaa Drain (QD). Chlorophenols (CPs) were the major group detected in the lake sediments followed by methylphenols (MPs) and nitrophenols (NPs). CPs were dominated by 2-, 4-, and 3-chlorophenols. Concentrations of CPs were higher at the north and northwestern parts of the MB indicating the influence of industrial effluents discharged into the lake. On the other hand, higher concentrations of NPs were observed at the south and southwestern parts of the MB, which is subjected to the discharge of agricultural and domestic effluents via QD. Results of the risk assessment revealed that phenol, cresols, 2,4-dinitrophenol, 4-NP, 2-CP, 2,3,4,6-tetrachlorophenol and 2,4-dimethylphenol are contaminants of concern and that adverse ecological effects could possibly occur to benthic species from the exposure to these pollutants in Lake Maryut and thus phenols should be included in monitoring and pollution prevention programs in the Egyptian aquatic environment affected by anthropogenic activities.  相似文献   
85.
依靠大自然:尼日利亚北部的野生食品   总被引:2,自引:0,他引:2  
引言 在西非半干旱地区,当地农村社区都使用许多野生植物来补充其日常食品的不足,他(她)们的日常食品主要来自靠雨水浇灌种植出来的主食,比如小米、高粱、花生和豇豆等.  相似文献   
86.
Various and diverse industrial safety areas were identified and grouped as under: general areas of safety, Special areas of safety and industry specific areas of safety.

General areas of safety are common to all industries and special areas of safety are relevant only if the selected industry has such nature of work or hazard and whereas the industry specific areas of safety refers to process safety of the industry. Three separate modules were prepared along with contents.

For conduction of the programme, the selected industry must be studied and the designed safety education programme modules have to be adapted by leaving irrelevant areas in special and industry specific areas of the designed safety modules. The implementation of safety education programme was carried out at Bharath Heavy Electricals Ltd, Trichy and Southern Railway workshop, Trichy, by adapting the designed modules to suit these industries as mentioned above.

Effectiveness is measured by the increase in safety awareness of the selected industrial workers (sample), who had already undergone such programmes with short falls conducted within the industry itself. Research Tool was prepared based on the contents of the adapted safety education modules and pre-test and post-test were conducted, data collected and analysed.

The results were statistically significant as confirmed by t-test analyses.  相似文献   

87.
This study employs insights largely derived from critical reflections on the common pool resources (CPR) theory to examine the current governance arrangements in place to manage the mangrove forest at Kisakasaka, in Zanzibar, Tanzania. Kisakasaka was used as a site for a community-based management pilot project of forest resources in Zanzibar. After some initial success in setting up a local management structure and regulating access to the mangrove for mainly charcoal production, there are now clear indications that forest conditions have deteriorated dramatically with concomitant ongoing resource use problems for local villagers who have relied heavily on forest resources as a source of cash income. Extra-local factors, such as urban population increases and associated market pressures for charcoal, are also conjectured to overlay and interact with the institutional problems at Kisakasaka. As a result, over concern about the deterioration in the condition of the mangrove forest, the responsible government authority decided not to renew the community-based governance arrangements after an initial five-year pilot period. While revealing the inadequacies of existing governance arrangements and of its relationship to deteriorating forest conditions at Kisakasaka, this study concludes by suggesting an approach to more fully understand forces driving local resource management and use.  相似文献   
88.
The acute salinity tolerance of three tropical freshwater cladoceran species, M. macleayi, C. rigaudii and D. brachyurum was determined. The existence of these species represented new records for Trinidad and Tobago, a tropical Caribbean island. It has a large oil based industry, in which, the primary effluent (saline produced water) is discharged directly into many freshwater systems. Cladoceran species are used routinely in temperate regions, to assess the impacts of chemicals and effluents in freshwater systems. However, relatively few studies have assessed the salinity tolerance of these organisms. Test organisms were assayed using seven salinity treatments (0, 1, 3, 5, 10, 15, 20, 25‰) prepared by volumetrically mixing natural filtered seawater with dilution water. C. rigaudii had a 48 h LC50 of 1.6‰, M. macleayi 1.5‰ and D. brachyurum <1‰. The CSmax (critical salinity maximum) for C. rigaudii and M. macleayi was 3‰ after 48 h, compared to 1‰ for D. brachyurum. There was no salinity value at which there was 100% survival. The resulting salinity response curve was a straight line which indicated that each species was intolerant of salt. Consequently, any of these can be considered as a representative freshwater organism for toxicity testing in Trinidad and Tobago.  相似文献   
89.
Geochemical study of groundwater from a structurally deformed granitic terrain near Hyderabad (India) was carried out to understand and evaluate the hydrogeochemical processes and quality of groundwater. Several trace elements (Fe, Mn, Be, Al, V, Cr, Co, Ni, Cu, Zn, As, Sr, Mo, Cd, Sb, Ba, Pb, U) along with major ions and minor elements were precisely estimated in shallow and drilled wells to know the suitability of water for drinking and irrigation purposes. Analytical data shows that pH and major ion chemistry in dug wells and bore wells do not vary significantly, while some trace elements (Fe, Mn, Al, Be, Co, Pb, U and Zn) vary in dug wells and bore wells, which can be attributed to differential mineral weathering and dissolution/precipitation reactions along fractures/joints. Although the water is not potable, it was found to be suitable for irrigation with little danger in the development of harmful level of exchangeable sodium. It is inferred that the chemical composition of the groundwater in this region is likely to have its origin from silicate weathering reactions and dissolution/precipitation processes supported by rainfall and groundwater flow.  相似文献   
90.
/ This study aims to investigate the ISO 14001 implementation process and its implications for regional environmental management. The region of Central Japan (known as Chubu in Japanese, which literally means center) was chosen for this case study. The study focuses on selected issues such as the: (1) trends and motives of private firms in the implementation of an ISO 14001-based environmental management system (EMS); (2) obstacles during system implementation; (3) role of the system in enhancing environmental performance within the certified organization; and (4) relation between the major stakeholders, local citizens, governments, and firms after adopting the system. To achieve these objectives, a questionnaire survey was mailed to all certified firms in the region. A 58% response was achieved overall. The results show that the main aims behind the adoption of ISO 14001 by firms in the Chubu region are to improve the environmental aspects within the enterprises and to enhance the employees' environmental awareness and capacity. The results have also shown that the ISO 14001-based EMS has had a great effect on a firm's environmental status as certified firms have claimed that natural resources such as fuel, water, and paper consumption have been more efficiently managed after adopting the system. Implementation of the system causes the firms to consider the role of the local people and the government in more effectively involving the local people in the firm's daily environmental activities. It also helps to enhance the environmental awareness among the local people. Adopting the system also promotes a better relation within the enterprises affiliated to the same group, such as more attention given by the parent firms (head offices) towards other firms working for the same group, or branches-mainly small and medium sized enterprises (SMEs)-in the field of EMS. Finally, the results show that firms give serious consideration to their final products' impacts on the environment. In other words, attention is given to life cycle analysis (LCA) among certified firms.  相似文献   
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