排序方式: 共有70条查询结果,搜索用时 46 毫秒
1.
Walia Niharika Dasgupta Nandita Ranjan Shivendu Ramalingam Chidambaram Gandhi Mansi 《Environmental Chemistry Letters》2019,17(4):1471-1483
Environmental Chemistry Letters - Nanoencapsulation is a promising technology allowing miniaturized dosage and administration of valuable volatiles, degradable bioactives and biologicals. The... 相似文献
2.
Mandal Dalia Dasgupta Singh Gaurav Majumdar Subhasree Chanda Protik 《Environmental science and pollution research international》2023,30(5):11119-11140
Environmental Science and Pollution Research - Apart from protecting the environment from undesired waste impacts, wastewater treatment is a crucial platform for recovery. The exploitation of... 相似文献
3.
Carl Folke Stephen Polasky Johan Rockstrm Victor Galaz Frances Westley Michle Lamont Marten Scheffer Henrik
sterblom Stephen R. Carpenter F. Stuart Chapin III Karen C. Seto Elke U. Weber Beatrice I. Crona Gretchen C. Daily Partha Dasgupta Owen Gaffney Line J. Gordon Holger Hoff Simon A. Levin Jane Lubchenco Will Steffen Brian H. Walker 《Ambio》2021,50(4):834
The COVID-19 pandemic has exposed an interconnected and tightly coupled globalized world in rapid change. This article sets the scientific stage for understanding and responding to such change for global sustainability and resilient societies. We provide a systemic overview of the current situation where people and nature are dynamically intertwined and embedded in the biosphere, placing shocks and extreme events as part of this dynamic; humanity has become the major force in shaping the future of the Earth system as a whole; and the scale and pace of the human dimension have caused climate change, rapid loss of biodiversity, growing inequalities, and loss of resilience to deal with uncertainty and surprise. Taken together, human actions are challenging the biosphere foundation for a prosperous development of civilizations. The Anthropocene reality—of rising system-wide turbulence—calls for transformative change towards sustainable futures. Emerging technologies, social innovations, broader shifts in cultural repertoires, as well as a diverse portfolio of active stewardship of human actions in support of a resilient biosphere are highlighted as essential parts of such transformations. 相似文献
4.
Assessment of groundwater pollution in West Delhi, India using geostatistical approach 总被引:3,自引:0,他引:3
Partha Pratim Adhikary H. Chandrasekharan Debashis Chakraborty Kalpana Kamble 《Environmental monitoring and assessment》2010,167(1-4):599-615
The exploration, exploitation, and unscientific management of groundwater resources in the National Capital Territory (NCT) of Delhi, India have posed a serious threat of reduction in quantity and deterioration of quality. The objective of the study is to determine the groundwater quality and to assess the risk of groundwater pollution at Najafgarh, NCT of Delhi. The groundwater quality parameters were analyzed from the existing wells of the Najafgarh and the thematic maps were generated using geostatistical concepts. Ordinary kriging and indicator kriging methods were used as geostatistical approach for preparation of thematic maps of the groundwater quality parameters such as bicarbonate, calcium, chloride, electrical conductivity (EC), magnesium, nitrate, sodium, and sulphate with concentrations equal or greater than their respective groundwater pollution cutoff value. Experimental semivariogram values were fitted well in spherical model for the water quality parameters, such as bicarbonate, chloride, EC, magnesium, sodium, and sulphate and in exponential model for calcium and nitrate. The thematic maps of all the groundwater quality parameters exhibited an increasing trend of pollution from the northern and western part of the study area towards the southern and eastern part. The concentration was highest at the southernmost part of the study area but it could not reflect correctly the groundwater pollution status. The indicator kriging method is useful to assess the risk of groundwater pollution by giving the conditional probability of concentrations of different chemical parameters exceeding their cutoff values. Thus, risk assessment of groundwater pollution is useful for proper management of groundwater resources and minimizing the pollution threat. 相似文献
5.
Indicator and probability kriging methods for delineating Cu, Fe, and Mn contamination in groundwater of Najafgarh Block, Delhi, India 总被引:1,自引:0,他引:1
Partha Pratim Adhikary Ch. Jyotiprava Dash Renukabala Bej H. Chandrasekharan 《Environmental monitoring and assessment》2011,176(1-4):663-676
Two non-parametric kriging methods such as indicator kriging and probability kriging were compared and used to estimate the probability of concentrations of Cu, Fe, and Mn higher than a threshold value in groundwater. In indicator kriging, experimental semivariogram values were fitted well in spherical model for Fe and Mn. Exponential model was found to be best for all the metals in probability kriging and for Cu in indicator kriging. The probability maps of all the metals exhibited an increasing risk of pollution over the entire study area. Probability kriging estimator incorporates the information about order relations which the indicator kriging does not, has improved the accuracy of estimating the probability of metal concentrations in groundwater being higher than a threshold value. Evaluation of these two spatial interpolation methods through mean error (ME), mean square error (MSE), kriged reduced mean error (KRME), and kriged reduced mean square error (KRMSE) showed 3.52% better performance of probability kriging over indicator kriging. The combined result of these two kriging method indicated that on an average 26.34%, 65.36%, and 99.55% area for Cu, Fe, and Mn, respectively, are coming under the risk zone with probability of exceedance from a cutoff value is 0.6 or more. The groundwater quality map pictorially represents groundwater zones as ??desirable?? or ??undesirable?? for drinking. Thus the geostatistical approach is very much helpful for the planners and decision makers to devise policy guidelines for efficient management of the groundwater resources so as to enhance groundwater recharge and minimize the pollution level. 相似文献
6.
Partha Dasgupta 《Sustainability Science》2007,2(1):5-11
In this lecture, I demonstrate how very different macroeconomic history begins to look if Nature is included as a capital
asset in production activities. The tentative conclusions I draw from the evidence are: (1) high population growth in the
world’s poorest regions (South Asia and sub-Saharan Africa) has been an obstacle to the achievement of sustainable economic
development there; relatedly, (2) when population growth is taken into account, the accumulation of manufactured capital,
knowledge, and human capital (health and education) has not compensated for the degradation of natural capital in South Asia
and sub-Saharan Africa and, in all probability, even in the UK and the US; (3) China is possibly an exception to (1) and (2).
This article is based on the Keynote Lecture delivered at the international symposium on “Sustainability in an Unequal World”,
held in Tokyo on November 24, 2006. The exposition relies on my book, Economics: A Very Short Introduction, Oxford University Press, Oxford, 2007.
The author is the Frank Ramsey Professor of Economics at the University of Cambridge and a Fellow of St. John’s College,
Cambridge. 相似文献
7.
Partha Dasgupta 《Resources Policy》1978,4(3):172-177
This paper analyses the relationship between social rates of discount to be used in benefit-cost analysis of investment projects and optimal intertemporal plans of capital accumulation and resource depletion. The discussion is conducted in the context of models that incorporate exhaustible natural resources. It is argued that discount rates are a derived concept and that they ought to be arrived at from a consideration of our sense of intergenerational justice and optimal programmes arrived at from intergenerational welfare criteria. 相似文献
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9.
Climate change and soil salinity: The case of coastal Bangladesh 总被引:1,自引:0,他引:1
This paper estimates location-specific soil salinity in coastal Bangladesh for 2050. The analysis was conducted in two stages: First, changes in soil salinity for the period 2001–2009 were assessed using information recorded at 41 soil monitoring stations by the Soil Research Development Institute. Using these data, a spatial econometric model was estimated linking soil salinity with the salinity of nearby rivers, land elevation, temperature, and rainfall. Second, future soil salinity for 69 coastal sub-districts was projected from climate-induced changes in river salinity and projections of rainfall and temperature based on time trends for 20 Bangladesh Meteorological Department weather stations in the coastal region. The findings indicate that climate change poses a major soil salinization risk in coastal Bangladesh. Across 41 monitoring stations, the annual median projected change in soil salinity is 39 % by 2050. Above the median, 25 % of all stations have projected changes of 51 % or higher. 相似文献
10.
Silver nanoparticle antimicrobial activity explained by membrane rupture and reactive oxygen generation 总被引:1,自引:0,他引:1
Silver nanoparticles are widely used as antimicrobial compounds based on empirical observations. However, there is few knowledge on the mechanism ruling the antimicrobial activity and toxicity of Ag nanoparticles. Here, we investigated this mechanism. Nano-Ag was synthesised by thermal co-reduction. Mutagenicity analysis was performed using Salmonella typhimurium histidine auxotrophic strains TA 98 and TA 100 at nano-silver concentrations of 100 to 500 µg per plate. Dose-dependent analysis for reactive oxygen species generation has been performed using 2,7-dichlorofluorescein diacetate dye. Membrane integrity has been analyzed at 260 nm, before and after treatment. We also used scanning electron microscopy, membrane permeabilization test, and superoxide formation determinations. Results show that the average particle size of Ag nanoparticle is 60.4 ± 3.8 nm. The minimum inhibitory concentration of Ag nanoparticles for E.coli is 30 µg/mL; the minimum bactericidal concentration is 40 µg/mL. Ames mutagenicity tests showed negative results, which may be explained by the antimicrobial activity of nano-silver. Bacterial inner wall were indeed ruptured, and cytoplasmic content was released after 5 min of treatment in a dose-dependent manner. We thus propose that reactive oxygen generation and alteration of membrane integrity and permeability are the major mechanism of antimicrobial activity of nano-silver. 相似文献