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1.
Understanding pollutant sorption, bioremediation of these pollutants, and their interactions with humic substances requires knowledge of molecular-level processes. New developments with nuclear magnetic resonance (NMR) experiments and labeled compounds have improved the overall understanding of these mechanisms. The advancements made with two-dimensional NMR show great promise, as structural information and hydrogen-carbon bond connectivity can be discerned. This communication presents the application of improved two-dimensional NMR methods, the double quantum filtered (DQF) correlation spectroscopy (COSY) and echo/anti-echo heteronuclear single quantum coherence (HSQC) experiments, for use in structural studies of humic substances. Both experiments were found to produce significant improvements over the conventional COSY and heteronuclear multiple quantum coherence (HMQC) experiments that have been previously employed in similar studies. The more sensitive echo/anti-echo HSQC experiment produced more cross-peaks with higher resolution when compared with the HMQC spectra. The DQF-COSY significantly suppressed the diagonal signals and allowed numerous signals previously hidden in the standard COSY experiment to be observed. These improvements will aid current characterization strategies of humic substances from soils, sediments, and water and their subsequent reactions with pollutants and microorganisms. 相似文献
2.
The addition of EDTA in phytoextraction studies has been reported to increase heavy metal accumulation in above-ground parts or to have no negative impact on the overall (root/shoot) accumulation levels in terrestrial plants. At a purely quantitative level, this study assessed the phytoextraction potential of a previously untested high-biomass terrestrial plant, Symphytum officinale L. (comfrey), in the presence of Pb and EDTA. In this hydroponic-based study, we report a small increase in shoot accumulation of Pb with EDTA but, conversely, the presence of EDTA in the nutrient medium markedly reduced the overall quantity of Pb in the plant root by at least 80%. The loss does not appear to be explained by EDTA acting alone, increased transport of Pb to the shoots, or anionic charge repulsion of the [PbEDTA]2? complex. The elusive action and negative effect of EDTA on Pb accumulation in S. officinale provides additional reasons towards a growing trend away from the use of EDTA as a chelating agent in phytoextraction. 相似文献
3.
Lily House-Peters Bethany Pratt Heejun Chang 《Journal of the American Water Resources Association》2010,46(3):461-472
House-Peters, Lily, Bethany Pratt, and Heejun Chang, 2010. Effects of Urban Spatial Structure, Sociodemographics, and Climate on Residential Water Consumption in Hillsboro, Oregon. Journal of the American Water Resources Association (JAWRA) 46(3):461-472. DOI: 10.1111/j.1752-1688.2009.00415.x Abstract: In the Portland metropolitan area, suburban growth in cities such as Hillsboro is projected to increase as people seek affordable housing near a burgeoning metropolis. The most significant determinants for increases in water demand are population growth, climate change, and the type of urban development that occurs. This study analyzes the spatial patterns of single family residential (SFR) water consumption in Hillsboro, Oregon, at the census block scale. The following research questions are addressed: (1) What are the significant determinants of SFR water consumption in Hillsboro, Oregon? (2) Is SFR water demand sensitive to drought conditions and interannual climate variation? (3) To what magnitude do particular census blocks react to drought conditions and interannual climate variation? Using ordinary least squares multiple regression and spatial regression methods, we found that base use, representing indoor water use, is dependent on household size and that seasonal use, representing external water use is dependent on both education level and the size of the property’s outdoor space. Spatial analysis techniques determined that although the water demand of the study area as a whole is not sensitive to drought conditions, certain individual census blocks do respond with a higher magnitude of water use. The most climate-sensitive census blocks tend to contain newer and larger homes, and have higher property values and more affluent and well-educated residents. 相似文献
4.
Lily Amelia D.A. Wahab C.H. Che Haron N. Muhamad C.H. Azhari 《Journal of Cleaner Production》2009,17(17):1572-1579
As the production of local vehicles increases, the impact of end-of-life vehicles (ELVs) wastes to the environment will also increase. ELVs recovery including reuse, remanufacture, and recycle apparently become a strategy in solving this environmental problem. This study identifies the existing conditions of automotive reuse in Malaysia by conducting some interviews in selected local automotive and automotive component manufacturers. Results from the interviews indicated that reuse of automotive components in newly manufactured vehicles has never been practiced by the selected companies. However, there is interest among respondents in developing automotive components for after-market reuse. Some strategies were proposed in this study to initiate automotive components reuse in the local automotive manufacturers including the establishment of the end-of-life directive, enhance research and development on design for reuse and increase reusability and economic benefits of reuse. 相似文献
5.
Kristina Diprose Richard Fern Robert M. Vanderbeck Lily Chen Gill Valentine Chen Liu 《Environmental Communication: A Journal of Nature and Culture》2018,12(5):672-685
Sustainability and sustainable development are prominent themes in international policy-making, corporate PR, news-media and academic scholarship. Its definitions are contested, however sustainability is associated with a three-pillar focus on economic development, environmental conservation and social justice, most recently espoused in the adoption of the UN Sustainable Development Goals in 2015. In spite of its common usage, there is little research about how sustainability is represented and refracted in public discourse in different national contexts. We examine British national press coverage of sustainability and sustainable development in 2015 in a cross-market sample of national newspapers. Our findings show that key international policy events and environmental and social justice frames are peripheral, while neoliberalism and neoliberal environmentalism vis-à-vis the promotion of technocratic solutions, corporate social responsibility and “sustainable” consumerism are the predominant frames through which the British news-media reports sustainability. This holds regardless of newspaper quality and ideological orientation. 相似文献
6.
Ian Christoplos Le Duc Ngoan Le Thi Hoa Sen Nguyen Thi Thanh Huong Lily Salloum Lindegaard 《Disasters》2017,41(3):448-467
How do disasters shape local government legitimacy in relation to managing climate‐ and disaster‐related risks? This paper looks at how local authorities in Central Vietnam perceive their social contract for risk reduction, including the partial merging of responsibilities for disaster risk management with new plans for and investments in climate change adaptation and broader socioeconomic development. The findings indicate that extreme floods and storms constitute critical junctures that stimulate genuine institutional change. Local officials are proud of their strengthened role in disaster response and they are eager to boost investment in infrastructure. They have struggled to reinforce their legitimacy among their constituents, but given the shifting roles of the state, private sector, and civil society, and the undiminished emphasis on high‐risk development models, their responsibilities for responding to emerging climate change scenarios are increasingly nebulous. The past basis for legitimacy is no longer valid, but tomorrow's social contract is not yet defined. 相似文献
7.
Ashutosh Bahugun Madhuri K. Lily Ashok Munjal Ravindra N. Singh Koushalya Dangwal 《环境科学学报(英文版)》2011,23(6):975-982
A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated
soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620)
using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and
confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively.
The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially
increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth
resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase
within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization
pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole
source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus
DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol. 相似文献
9.
Lily Maynard 《Environmental Communication: A Journal of Nature and Culture》2018,12(2):177-190
Zoos and aquaria are controversial institutions, vilified by animal rights activists and championed by those who value their entertainment and educational resources. Examining media frames of these institutions can identify public perspectives. A qualitative content analysis was conducted for print and online magazine articles that discussed zoos and aquaria in North America. Sixty-five articles were analysed, and eight different frames were identified. The diverse frames highlight the differing roles of zoos and aquaria. Most of the articles were positive and supportive of zoos; 11% were negative. Animal welfare was the most common frame, from both positive and negative perspectives. Other frames, such as conservation and education, were less prevalent in the sample than expected, since zoos and aquaria portray themselves to be leaders in these fields. The unbalanced media discourse and small publication rate over the four years sampled suggest opportunities for increased media engagement on zoos and aquaria. 相似文献