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1.
The various analytical protocols that have been developed to aid the measurement of nitrite within environmental samples have been critically appraised and their applicability to field measurement assessed. The present communication presents a perspective on current techniques and technologies encompassing spectroscopic, electrochemical and chromatographic methodologies and highlights those that are liable to emerge in the near future. Commercial devices have been included and where appropriate the advantages and limitations posed by their operation within field contexts have been described. 相似文献
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Poly-β-hydroxybuyrate (PHB) is a carbon—energy storage material which is accumulated as intracellular granule in variety of
microorganism under nutrient starved conditions. Solid PHB is a biodegradable thermoplastic polymer and is utilizable in various
ways similar to many conventional plastics. Ralstonia eutropha (Alcaligenes sp.), a gram negative bacteria accumulates PHB as insoluble granules inside the cells when nutrients other than carbon are
limited. In this report effort has been made to analyze PHB granule synthesis inside Alcaligenes sp. NCIM 5085 by transmission electron microscopy and qualitative estimation of PHB was carried out by fourier transform
infrared spectroscopy which provide better precision compared to other conventional techniques previously applied for PHB
determination. Maximum PHB concentration of 2.20 ± 0.40 g/L and cell biomass of 3.42 ± 0.20 g/L was obtained after 48.0 h
of fermentation. Leudking-Piret equation deduced mixed growth associated product formation which varies from earlier reports. 相似文献
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Kuheli Dutt 《Environment, Development and Sustainability》2009,11(4):705-723
This paper examines the environment-income relationship in the context of the Environmental Kuznets Curve (EKC), and explores
the possible role that factors like governance, political institutions, socioeconomic conditions, and education play in influencing
this relationship. The results suggest that the EKC exists for carbon dioxide emissions for cross-country data over the period
1984–2002. However, there is nothing automatic about this relationship; policies designed to protect the environment may be
responsible for this phenomenon. Two other significant findings are: one, countries with better quality of governance, stronger
political institutions, better socioeconomic conditions and greater investment in education have lower emissions; and two,
only around 15% of the countries in the dataset have reached income levels high enough to be associated with an unambiguous
decline in emissions. The implications of these results are discussed within the context of the international environmental
policy arena and the Kyoto Protocol. One of the main objectives of this paper is to bridge the gap between studies conducted
on the EKC and developments in the international environmental policy arena. As a final note this paper emphasizes that one
needs to connect the body of knowledge on the EKC hypothesis to the international environmental policy arena, despite the
apparent difficulty of doing so. One hopes that future studies will further build on this line of thought.
相似文献
Kuheli DuttEmail: |
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Shanmugasundaram R Jeyalakshmi T Dutt MS Murthy PB 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(1):43-45
Larvicidal effect of neem (Azadirachta indica) and karanja (Pongamia glabra) oil cakes (individuals and combination) was studied against mosquito species. Both the oil cakes showed larvicidal activity against the mosquito species tested. The combination of neem and karanja oil cakes in equal proportion proved to have better effect than the individual treatments. The combination of the two oil cakes recorded an LC95 of 0.93, 0.54 and 0.77% against the mosquitoes, Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi respectively The increase in efficacy of the combination treatment over individuals in all the mosquito larvae tested was found to range about 4 to 10 fold in terms of LC50 and 2 to 6 fold in terms of LC95. 相似文献
6.
Singh Amandeep Tiwari Rupasi Dutt Triveni 《Journal of Material Cycles and Waste Management》2021,23(4):1544-1562
Journal of Material Cycles and Waste Management - Global waste production is pegging at unforeseen heights and alarming for its sustainable management. Information and Communication Technologies... 相似文献
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A. J. Dutt 《Environmental monitoring and assessment》1991,19(1-3):495-506
The wind environment at ground leven in built-up areas is influenced by the extremely complex interaction amongst incident wind, mean vertical velocity gradient, turbulence and the shapes, sizes and layouts of building. Random layout of buildings could generate zones of overspeed and vortices in the connecting passage way between buildings, terraces, opensided shelters, courtyards, which could potentially cause unpleasantness, hazard from resuspended particulates, and airborne rain penetration into the buildings. The paper presents the results of two case studies comprising field measurements made within the Kent Ridge Campus, National University of Singapore, using DANTEC 54N10 Multichannel Flow Analyser and Probes. Results are presented in terms of non-dimensional windspeed coefficients. It is concluded that there is significant increase in windspeed due to channel and venturi effects. This information provides useful guidelines for building plans and layouts to the architects and engineers. 相似文献
8.
Abhishek Dutt Tripathi Ajay Yadav Alok Jha S. K. Srivastava 《Journal of Polymers and the Environment》2012,20(2):446-453
In the present study, depending upon the availability and cheaper cost, different carbon source were tested for the production of PHAs (Polyhydroxyalkonoates) by soil bacterium Pseudomonas aeruginosa and it was found that sugar refinery waste (cane molasses) produced the maximum PHA (biodegradable polymer) which is precursor for bio-plastic development. Urea served as potent nitrogen source over other inorganic nitrogen sources in bio-plastic synthesis. Effect of different physical parameters viz; pH, temperature and agitation speed were also studied on PHA production. Batch cultivation kinetics under optimized cultural and physical condition showed maximum cell mass and PHA concentration of 7.32?±?0.2 and 5.60?±?0.3?g/L, respectively after 54.0?h of cultivation. Sugar refinery waste (Total sugar 4%) and urea (0.8%) improved the economics of the process which exhibited a yield (YP/X) of 0.70 with productivity of 0.11?g/L/h. PHA was further characterized as PHB by using Fourier Transform Infra-red Spectroscopy (FT-IR). 相似文献
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Landscapes of Protection: Forest Change and Fragmentation in Northern West Bengal,India 总被引:1,自引:0,他引:1
Harini Nagendra Somajita Paul Sajid Pareeth Sugato Dutt 《Environmental management》2009,44(5):853-864
In the tropics and sub-tropics, where high levels of biodiversity co-exist with some of the greatest levels of population
density, achieving complete exclusion in protected area contexts has proved close to impossible. There is a clear need to
recognize that parks are significantly impacted by human–environment interactions in the larger landscape within which they
are embedded, and to move the frontier of research beyond the boundaries of protected areas in order to examine larger landscapes
where multiple forms of ownership and access are embedded. This research evaluates forest change and fragmentation between
1990 and 2000, in a landscape surrounding the Mahananda Wildlife Sanctuary in the Indian state of West Bengal. This protected
forest is bounded to the south by a less intensively protected area, the Baikunthapur Reserve Forest, and surrounded by a
mosaic of unprotected, largely private land holdings. Results indicate differences in the extent and spatial pattern of forest
cover change in these three zones, corresponding to different levels of government protection, access and monitoring. The
two protected areas experience a trend toward forest regrowth, relating to the cessation of commercial logging by park management
during this period. Yet, there is still substantial clearing toward peripheral areas that are well connected to illegal timber
markets by transportation networks. The surrounding landscape, although experiencing some forest regrowth within less intensively
cultivated tea plantations, is also becoming increasingly fragmented, with potentially critical impacts on the maintenance
of effective wildlife corridors in this ecologically critical region. 相似文献
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