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41.
ABSTRACT

The main purpose of Green Supply Chain Management (GSCM) is to improve the quality of supply chain management strategies and environmental performance. As per current statistics, the chemical industry is growing fast in Bangladesh. In order to compete for global competition, GSCM is essential in this sector. This paper proposes a systematic approach of structural framework whose aim is to enhance the probability of constructive implementation of GSCM in the field chemical industry in Bangladesh. Therefore, this framework evaluates the appropriate interrelationship along with the drivers of GSCM in the chemical industry. In total, eight drivers were finalized from an associated literature review with the help of survey and by taking expert opinions via the Delphi methodology. In addition to MICMAC analysis, the driving and the dependence powers for all the drivers were determined. Moreover, the structural frameworks for the drivers were developed by means of total interpretive structural modeling (TISM) technique. As a result, the findings indicate that the most significant driver was supplier pressure and willingness and the most important barrier was high cost. Finally, the main objective of this research is expected to help industrial managers to evaluate and understand the critical areas where they should emphasize to implement GSCM in the chemical industry.  相似文献   
42.
Environmental Science and Pollution Research - The Ganges River is one of the biggest transboundary streams in the Indian sub-continent. The significant part of this waterway channel drains one of...  相似文献   
43.
Study of harmful algal blooms in a eutrophic pond, Bangladesh   总被引:2,自引:0,他引:2  
The purpose of this research was to analyze the underlying mechanisms and contributing factors related to the seasonal dynamic of harmful algal blooms in a shallow eutrophic pond, Bangladesh during September 2005–July 2006. Two conspicuous events were noted simultaneously throughout the study period: high concentration of phosphate–phosphorus (>3.03; SD 1.29 mg l???1) and permanent cyanobacterial blooms {>3,981.88 × 103 cells l???1 (SD 508.73)}. Cyanobacterial blooms were characterized by three abundance phases, each of which was associated with different ecological processes. High nitrate–nitrogen (>2.35; SD 0.83 mg l???1), for example, was associated with high cyanobacterial abundance, while low nitrate–nitrogen (0.36; SD 0.2 mg l???1) was recorded during moderate abundance phase. Extremely low NO3–N/PO4–P ratio (>3.55, SD 2.31) was recorded, and all blooming taxa were negatively correlated with this ratio. Cyanobacterial blooms were positively correlated with temperature (r?=?0.345) and pH (0.833; p?=?0.05) and negatively correlated with transparency (r?=???0.956; p?=?0.01). Although Anabaena showed similar relationship with water quality parameters as cyanobacteria, the co-dominant Microcystis exhibited negative relationship with temperature (r?=???0.386) and nitrate–nitrogen (r?=???0.172). This was attributed to excessive growth of Anabaena that suppressed Microcystis’s growth. Planktothrix was the third most dominant taxa, while Euglena was regarded as opportunistic.  相似文献   
44.
Criteria and indicators assessment is one of the ways to evaluate management strategies for mountain watersheds. One framework for this, Integrated Watershed Management (IWM), was employed at Chittagong Hill Tracts region of Bangladesh using a multi-criteria analysis approach. The IWM framework, consisting of the design and application of principles, criteria, indicators, and verifiers (PCIV), facilitates active participation by diverse professionals, experts, and interest groups in watershed management, to explicitly address the demands and problems to measure the complexity of problems in a transparent and understandable way. Management alternatives are developed to fulfill every key component of IWM considering the developed PCIV set and current situation of the study area. Different management strategies, each focusing on a different approach (biodiversity conservation, flood control, soil and water quality conservation, indigenous knowledge conservation, income generation, watershed conservation, and landscape conservation) were assessed qualitatively on their potential to improve the current situation according to each verifier of the criteria and indicator set. Analytic Hierarchy Process (AHP), including sensitivity analysis, was employed to identify an appropriate management strategy according to overall priorities (i.e., different weights of each principle) of key informants. The AHP process indicated that a strategy focused on conservation of biodiversity provided the best option to address watershed-related challenges in the Chittagong Hill Tracts, Bangladesh.  相似文献   
45.
Forests represent more than just a livelihood to many people in developing countries. In Bangladesh, for example, overwhelming poverty and socio-economic pressures have resulted in an unstable situation where intensive pressure on forest resources is having increasingly negative consequences for the population. Some studies have evaluated the benefits of people-oriented forestry activities from an investment, as well as a participant, point of view. In the study area located in the Tangail Forest Division, a total of 11,854 ha of woodlot, 2704 ha of agroforestry and 945 km of strip plantations have been raised in a benefit-sharing program that is inclusive of land encroachers and other economically disadvantaged people. Since 2000-2001, a total of 3716 ha of woodlot, 890 ha of agroforestry and 163 km of strip plantations have been harvested to the benefit of 6326 individuals. Investment analysis indicates that woodlot plantation is not financially viable but agroforestry is the most profitable. These results were somewhat unexpected since initial analysis suggested that the woodlot plantation profit would be greater than, or at least equal to, that of the agroforestry plantation if the number of planted seedlings per unit area was taken into account. The per unit area net present value (NPV) was highest in the agroforestry plantation ($1662) and negative in the woodlot plantation (-$397). The benefit cost ratio (BCR) was also highest in the agroforestry plantation (1.64) and lowest in the woodlot plantation (0.86). This study also showed that some individuals who were formally classified as encroachers have now become vital stakeholders. On average, participants received $800, $1866 and $1327 over the course of 13 years from strip, agroforestry and woodlot plantations, respectively. Average annual return per participant was $62, $144 and $102, respectively, which was in addition to each individual's yearly income. This added income is a significant contribution to monetary resources and improves socio-economic conditions at a grass roots level. Overall then this program can be considered a financial success as a plantation raising strategy. However, despite this financial progress, the program cannot be considered a true form of participatory people-oriented forestry because it shows serious deviations from the original concept or model for participatory people-oriented forestry that is outlined in the project document. These discrepancies are especially notable with regard to (i) beneficiary selection, (ii) gender equity, (iii) professional attitude and corruption, (iv) funding and (v) program approach. However, other countries faced with similar challenges of forest overuse and degradation may adopt this practice for achieving self-reliance and environmental stability.  相似文献   
46.
Groundwater and sediment samples were collected along a flow path in the Aquia aquifer (Paleocene), Maryland in order to examine and study the factors influencing "evolution" of arsenic (As) in these groundwaters. The Aquia crops out near Washington, DC, where it is unconfined, and extends approximately 90 km down dip to the south and east towards and beneath the Chesapeake Bay. The studied flow path was chosen owing to (i) the number of accessible wells, (ii) differences in total dissolved As concentrations in groundwaters from some of the sampled wells, which reach values >/=667 nmol kg(-1) or >/=50 ppb, and (iii) the distinct difference in total dissolved As concentrations in Aquia groundwaters between the northern and southern portions of the study area. In groundwater samples, in situ separation of inorganic As species [As(III) and As(V)] were performed by using anion exchange chromatography. Subsequently, As concentrations were determined by inductively coupled plasma mass spectrometry. In situ measurements of Fe concentrations and speciation, dissolved S(-II) concentrations, pH, alkalinity, and oxidation-reduction potential (Eh) were determined to establish the oxidation-reduction conditions and solution chemistry along the flow path. Concentrations of As in 12 analyzed groundwater samples range from approximately 0.75 to 1 072 nmol kg(-1), and As(III) concentrations ranging from 0.24 to 980 nmol kg(-1) appears to be the dominant form of As in solution. 50% of the studied wells yielded groundwaters with concentrations that exceed the US EPA's Maximum Contaminant Level for As in drinking water of 133 nmol kg(-1) or 10 ppb. In order to examine the solid phase speciation of As within the aquifer sediments, we collected a number of Aquia sediment samples from a drill core that was archived at the Maryland Geological Survey. These sediment samples were evaluated using a previously established sequential extractions procedure. Solid phase As concentrations range between 973 and 2,012 nmol kg(-1). Additionally, petrographic, X-Ray diffraction and diffuse reflectance spectroscopy analyses of the Aquia sediments reveal presence of glauconite, and smectite along with goethite and hematite within the samples. Here, we present the possible mechanisms responsible for the elevated As concentrations in the studied groundwaters of the Aquia aquifer.  相似文献   
47.
Journal of Material Cycles and Waste Management - Every year, a massive volume of textile waste is disposed of in a landfill or incinerated, contributing to resource loss and environmental...  相似文献   
48.
Pentachlorophenol (PCP) is a fungicide used in wood protection and a herbicide used against weeds in various crops2–4, especially in rice. Up to 1971, it contributed more than 50% to the herbicides used in Japan. However, because it has a high fish- and shellfish-toxicity, its application to paddy fields has been restricted since 1971. Today, PCP is still in use to a fair extent in paddy fields and upland crops either as a single herbicide or in combination with others4. Numerous publications are concerned with its abiotic decomposition5–8 including photomineralization9 and microbial degradation4,10–16 leading to the formation of carbon dioxide17–18. Furthermore, studies with bacteria using PCP as a sole carbon source have been done13,19. At least ten metabolites have been isolated from soil and identified4,10–11,14, 20–21, the main metabolic steps being methylation of the hydroxyl group, dechlorination resulting in tetrachloro- and trichlorophenols, and hydroxylation to chlorinated hydroquinones or catechols.According to our knowledge, no reports are available on identification of metabolites in the protected organisms, the higher plants. In one study it has been suggested that cotton plants accumulate and metabolize PCP, but no metabolites were reported22. This first paper on our respective experiments deals with the isolation and identification of a metabolite found in rice plants.  相似文献   
49.
Platanista gangetica ) are threatened in Bangladesh from the effects of dams, large embankment schemes, dredging, fisheries bycatch, directed hunting, and water pollution. Visual surveys of the section of the Jamuna River located between the divergence of the Old Brahmaputra River and the confluence of the Padma River and the section of the Kushiyara River located between the Bangladesh–India border and the confluence of the Korangi River recorded a sighting rate of 0.13 sightings/km (mean group size = 1.8 dolphins) and 0.08 sightings/km (mean group size = 3.8 dolphins), respectively. These sections of river were considered to be priority areas for investigation because several water development projects have already been constructed and more are planned for the areas. During the surveys we examined the remains of dolphins caught accidentally in plastic gillnets and observed fishermen catching the fish species Clupisoma garua using dolphin oil and body parts as a fish attractor. Additional studies are needed to assess the status of dolphins and effects of water development and fisheries bycatch. Feasibility studies should be conducted on designating dolphin/fish sanctuaries and creating artificial habitat or enhancing existing habitat in eddy countercurrent scour pools to mitigate deleterious impacts. The environmental requirements of river dolphins reflect the needs of productive and biotically diverse tropical rivers.  相似文献   
50.
Flooding of wetland or agricultural soils can result in substantial alteration of the pore water trace metal profiles and potentially also influence the bioavailability of other trace elements adsorbed to the insoluble oxides. Experimental microcosms were used to quantify the impact of rice (Oryza sativa) plants across an entire growing cycle on the concentrations of Mn2+ and Fe2+ in two soil types (red sodosol and grey vertosol). Two water management treatments were included: a standard flooded treatment and a saturated treatment (?3?kPa). Soil pore water profiles were established from samples collected at four sampling depths (2.5, 7.5, 15 and 25?cm) on 50 occasions. Fe2+ and Mn2+ concentrations were higher in flooded soil than in saturated soil and greatest at a depth of 7.5?cm. The presence of rice plants increased Mn2+ concentrations in flooded soils, but tended to decrease Mn2+ concentrations in saturated soils. The influence of rice plants on Fe2+ concentrations was greatest at a depth of 7.5?cm. Changes in soil pore water Fe2+ and Mn2+ concentrations due to the presence of rice plants were correlated with flowering and reproduction.  相似文献   
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