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1.
The Rio+20 summit of the United Nations in Brazil in 2012 committed governments to formulate a set of sustainable development goals (SDGs) that would be integrated into the Millennium Development Goals (MDGs) following its expiration in 2015. This decision has pushed sustainable development agenda into the limelight of development once again. Meanwhile, we note that the development agenda of many developing countries has been dominated by neoliberal orientation driven by market reforms, social inequality, and a move towards enhancing the economic competitiveness of the supply side of the economy. In this paper, we discuss the relationship between neoliberal economic agenda and sustainable development. We do so by examining how neoliberal policies of privatisation, trade liberalisation and reduction in governments spending stand to affect the attainment of sustainable development ideals and their implications on the post-2015 Sustainable Development Goals. The paper then suggests that relying solely on the mechanisms of the market in governing and allocating environmental resources is necessarily insufficient and problematic and therefore calls for a new approach—one which goes beyond just recognising the interdependency among social, environmental and economic goals and places issues of equity and addressing unfavourable power relations at the centre of interventions aimed at achieving the ideals of sustainable development.  相似文献   
2.
With increasing environmental challenges confronting our planet, colleges and universities are trying different approaches for minimizing their adverse environmental impacts. Among the approaches being used to revitalize campus sustainability efforts, new waste management strategies have included attempts to improve campus-recycling programs. This paper presents select findings from a comprehensive study at a large, Tier I university aimed at, among other things, informing university administration and decision makers working on the planning and implementation of a new campus-wide recycling facility and program. The researchers used a mixed-method approach to help them develop an understanding of the campus community's (1) perceived barriers to recycling, (2) recycling knowledge, (3) program preferences, and (4) environmental attitudes. The results from a web-based survey (n = 3896, RR1 = 24.9%) suggest, communication efforts for recycling programming should focus more on messages concerning what, how, and where to recycle rather than messages on why to recycle. Furthermore, the results suggest recycling-related publicity approaches should differentiate their mode and content for different segments of the community.  相似文献   
3.
Urban, suburban and rural background air samples were collected in southern Ghana in 2008 employing polyurethane foam disc passive air samplers (PAS). PAS were analysed for organochlorine pesticides (OCPs), namely hexachlorocyclohexanes (α-, β-, γ- and δ-hexachlorocyclohexane), dichlorodiphenyltrichloroethane including metabolites (o,p'- and p,p'-DDT, DDE and DDD), hexachlorobenzene, pentachlorobenzene, aldrin, dieldrin, endrins (endrin, endrin aldehyde and endrin ketone), isodrin, heptachlors (heptachlor, heptachlor epoxide A and heptachlor epoxide B), chlordanes (α-, β-chlordane, oxychlordane and trans-nonachlor), endosulfans (α- and β-endosulfan and endosulfan sulphate), methoxychlor and mirex using a gas chromatograph coupled to a mass spectrometer. The levels of OCPs ranged for the individual pesticides from below limit of quantification to 750 pg m(-3) (for α-endosulfan), and current agricultural application seemed to be the main primary source of most abundant pesticides. Re-volatilization of previously used pesticides from contaminated soils could not be ruled out either as potential secondary source of contamination, especially in warm and dry seasons and periods of intensive agricultural activities. Higher atmospheric concentrations were observed in November and December during the dry season compared to lower concentrations observed in June, July and August when the country experiences heavy rains. The highest seasonal variation was observed for currently used pesticides as α-endosulfan. A p,p'-DDT/p,p'-DDE ratio suggested recent inputs of fresh technical DDT.  相似文献   
4.
不同施氮处理下旱作农田土壤CH_4、N_2O气体排放特征研究   总被引:6,自引:0,他引:6  
依托甘肃农业大学布设在定西市李家堡镇的长期施氮定位实验,对不同施氮农田CH4和N2O气体通量,采用静态箱-气相色谱法进行小麦生育期的连续观测,并对影响通量变化的环境因子同期观测.结果表明:5个施氮处理下(0、52.5、105、157.5、210 kg·hm-2),旱作农田土壤在小麦全生育期内表现为CH4累积通量的汇和N2O累积通量的源;且不施氮处理时,CH4累积吸收通量最大;施氮量为210 kg·hm-2时,土壤CH4的累积吸收通量所受抑制最大,即土壤CH4累积吸收通量随施氮量升高而降低.相反,不施氮处理时,土壤N2O的累积排放通量最小,施氮量为210 kg·hm-2时,土壤N2O的累积排放通量最大,土壤N2O累积排放通量随施氮量的增加而增大.综合分析,施氮量增大会抑制全生育期旱作春小麦田土壤CH4吸收通量,提高土壤N2O的排放通量.因此,合理控制施氮量有利于生育期旱作农田土壤减排.CH4平均吸收通量随土壤温度的升高而降低,随土壤水分的升高而升高;相反,N2O平均排放通量随土壤温度的升高而升高,随土壤水分的升高而降低.5~10 cm层次的土壤温度与CH4平均吸收通量呈极显著线性负相关,与N2O平均排放通量呈显著正相关.5~10 cm层次的土壤水分与CH4平均吸收通量呈极显著线性正相关,与N2O平均排放通量呈显著负相关.  相似文献   
5.
Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2CO3-31.5 mol% Na2COr-25 mol% K2CO3) and a binary (29 mol% Na2CO3-71 mol% K2CO3) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system.  相似文献   
6.
Wastepaper is the largest fraction of solid waste. Flotation deinking plays an essential role in the product quality and process cost of wastepaper recycling. This paper investigated the effect of ink types and printing processes on flotation deinking. Examination of ink types in this study revealed that newsprint oil-based offset-cold and offset-heat inks contain substantial oil (45 to 60%) and resin (5 to 35%); water-based ink contains water (40%) and resin (polystyrene, 30%); and these inks are liquids with densities around 1 g/cm3 at 25 °C. On the other hand, photocopy and laser-print toners were found to be solid powders with particle diameters of about 20 μm, densities of 1 to 1.5 g/cm3, and a composition that consists primarily of styrene-acrylate copolymers (60 to 90%). Except for water-based ink, which is water soluble, all inks in their initial state are hydrophobic. It was found that for newsprint oil based offset-cold inks there is little change in their surface chemical properties, and their hydrophobic character is retained. These inks in the newsprint wastepaper pulp can be effectively removed by flotation. On the other hand, it was found that during the printing processes, the toner particles undergo polymerization (fusion) and oxidation with the subsequent formation of peroxide bonds due to exposure to heat, light, and oxygen (air). The fusion due to polymerization causes bonding to the paper fibers and the creation of larger toner particle sizes. The oxidation creates a greater polarity at the toner particle surface. These effects account for the poor efficiency in the flotation deinking of office waste. In order to improve office wastepaper recycling, it is evident, based on this study and policy considerations, that there is a need to find ways of improving the efficiency and effectiveness of flotation deinking by modification of the surface properties of printed toner particles, or designing new toner particles.  相似文献   
7.
Public parks are important to urban environments, residents, and visitors. Among other functions, they provide environmental services, such as air and water purification, and they increase both recreational opportunities and the attractiveness of the urban environment. Because of their importance, urban parks serve as public spaces that provide visitors and urban residents with rights to the city. This paper identifies the dearth of urban public parks in Accra-Tema city-region as worrying. The Accra Plan 1958 underscored the significance of green spaces and designated the coastal strip for parks development but the areas have been lost to various urban uses. We argue that the continual neglect of public parks within urban planning and community development schemes in the Accra-Tema city-region is a major concern because it is depriving the citizens a right to the city and its public spaces. A number of factors have worked adversely against the provision of public parks and green spaces in the city-region. These include development pressures, undue political interference, a complex land delivery system, and ad hoc planning. The paper concludes by offering policy suggestions as to how to resolve the dearth of parks and green spaces in the city-region.  相似文献   
8.
Although polychlorinated biphenyls have never been manufactured in Ghana, it has been used extensively as dielectric fluid in electric transformers and capacitors. However, very little is known of its health and environmental impacts by both managers of these transformers and capacitors and also the general public. This work therefore seeks to explore INAA as a possible alternative to screening transformer oils for PCBs by determining the total chlorine content. The total chlorine content of transformer oil samples from Ghana that tested positive and some randomly selected samples that tested negative from screening using CLOR-N-OIL test kits, have had their total chlorine estimated. INAA using the Research Reactor located at the Ghana Atomic Energy Commission was used to estimate the total chlorine content of the oil samples. Neutron Activation and gamma ray spectroscopy using HPGe detector coupled to MAESTRO 32 software was used to determine the total chlorine content by integrating the peak area of the spectrum into a simplified program that was developed from the activation equation. Instrumental Neutron Activation Analysis was able to validate the result obtained from the test kits screening with accuracy 7.5%.The minimum total chlorine content of the positive samples determined by NAA was 71.34 μg g−1.  相似文献   
9.
Abstract

Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2 CO3 –31.5 mol% Na2 CO3 –25 mol% K2 CO3 ) and a binary (29 mol% Na2 CO3 –71 mol% K2 CO3 ) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2 SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2 SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system.  相似文献   
10.
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