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Fronds of Spirodela polyrrhiza were treated with different concentrations of Cd and malathion singly and in combinations. Results showed that Cd toxicity was more than malathion. The chlorophyll content was more severely affected by Cd (EC-50 of >1.0 µg ml–1); however, its toxicity was ameliorated in the presence of malathion (EC-50 of 2.0 µg ml–1). Although biomass and frond numbers were least affected by these toxicants, at initial treatment durations fronds multiplication was more severely affected than biomass with an increase in treatment durations. The importance of these findings have been discussed in relation to metal abatement and biomonitoring.NBRI Publication No. (432) NS. 相似文献
885.
Tapping the leakages: Methane losses, mitigation options and policy issues for Russian long distance gas transmission pipelines 总被引:1,自引:0,他引:1
Stefan Lechtenbhmer Carmen Dienst Manfred Fischedick Thomas Hanke Roger Fernandez Don Robinson Ravi Kantamaneni Brian Gillis 《International Journal of Greenhouse Gas Control》2007,1(4):387-395
The Russian natural gas industry is the world's largest producer and transporter of natural gas. This paper aims to characterize the methane emissions from Russian natural gas transmission operations, to explain projects to reduce these emissions, and to characterize the role of emissions reduction within the context of current GHG policy. It draws on the most recent independent measurements at all parts of the Russian long distance transport system made by the Wuppertal Institute in 2003 and combines these results with the findings from the US Natural Gas STAR Program on GHG mitigation options and economics.With this background the paper concludes that the methane emissions from the Russian natural gas long distance network are approximately 0.6% of the natural gas delivered. Mitigating these emissions can create new revenue streams for the operator in the form of reduced costs, increased gas throughput and sales, and earned carbon credits. Specific emissions sources that have cost-effective mitigation solutions are also opportunities for outside investment for the Joint Implementation Kyoto Protocol flexibility mechanism or other carbon markets. 相似文献
886.
This paper evaluates the use of a nickel nanoparticle (NiNP) interlayer for making hermetic joints in 316L stainless steel substrates via diffusion brazing. Different NiNP inks were prepared using commercial nanopowder (~9 nm) and in-house synthesized nanoparticles. Syringe pump deposition of ~9 nm NiNP ink and diffusion brazing at 900 °C for 30 min under 2 MPa resulted in a hermetic joint up to the tested pressure of 70 psi. In-house synthesis of NiNPs was carried out in ethylene glycol by the reduction of NiCl2·6H2O in the presence of hydrazine (N2H4) as a reducing agent. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) results confirm the presence of pure fcc-Ni with an average particle size of 5.4 ± 0.9 nm. An as-synthesized suspension of NiNPs was patterned onto 316L stainless steel laminae via automated dispensing to a thickness of ~3 μm and bonded at 800 °C for 30 min at a pressure of 2 MPa. The diffusion-brazed test article was also found to be hermetic up to 70 psi. An examination of the bond line using scanning electron microscopy (SEM) showed good uniformity and continuity. 相似文献
887.
Asbjørn Aaheim Ranjith Gopalakrishnan Rajiv Kumar Chaturvedi N. H. Ravindranath Anitha D. Sagadevan Nitasha Sharma Taoyuan Wei 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):229-245
We examine the potential for adaptation to climate change in Indian forests, and derive the macroeconomic implications of
forest impacts and adaptation in India. The study is conducted by integrating results from the dynamic global vegetation model
IBIS and the computable general equilibrium model GRACE-IN, which estimates macroeconomic implications for six zones of India.
By comparing a reference scenario without climate change with a climate impact scenario based on the IPCC A2-scenario, we
find major variations in the pattern of change across zones. Biomass stock increases in all zones but the Central zone. The
increase in biomass growth is smaller, and declines in one more zone, South zone, despite higher stock. In the four zones
with increases in biomass growth, harvest increases by only approximately 1/3 of the change in biomass growth. This is due
to two market effects of increased biomass growth. One is that an increase in biomass growth encourages more harvest given
other things being equal. The other is that more harvest leads to higher supply of timber, which lowers market prices. As
a result, also the rent on forested land decreases. The lower prices and rent discourage more harvest even though they may
induce higher demand, which increases the pressure on harvest. In a less perfect world than the model describes these two
effects may contribute to an increase in the risk of deforestation because of higher biomass growth. Furthermore, higher harvest
demands more labor and capital input in the forestry sector. Given total supply of labor and capital, this increases the cost
of production in all the other sectors, although very little indeed. Forestry dependent communities with declining biomass
growth may, however, experience local unemployment as a result. 相似文献
888.
Kisku GC Pandey P Negi MP Misra V 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(6):831-838
Uptake and accumulation of metals in crops may cause possible health risks through food chain. A field survey was conducted to investigate the accumulation of potentially toxic metals contamination in soil and plants irrigated with complexed industrial effluents. Concentration of Zn, Cu and Pb was 205-255,101-130,118-177 microg g(-1) in rhizosphere soils and 116-223, 57-102 and 63-95 microg g(-1) d. wt. in root and 95-186, 44-75 and 27-58 microg g(-1) d. wt. in shoot, respectively. The trend in Cu and Pb was in the order: soil > root > shoot > seed while in Zn it was soil > root > seed > shoot. Roots accumulated a larger fraction of soil Cu (70%) > Zn (67%) > Pb (54%). Bioaccumulation coefficient of soil to root ranged from 51-98 for Zn, 54-85 for Cu and 43-63 for Pb.Analysis of variance showed marginal change in bioaccumulation coefficient, noticed between plants (p > 0.05) while it varied significantly (p < 0.01) between tissues and metals. It increased from root to seed/fruit (root > shoot > seed/fruit) while decreased between metals from Zn to Pb (Zn > Cu > Pb). Out of the three, two Cu and Pb accumulated to phyotoxic levels while Zn was within threshold limit of phytotoxicity. 相似文献
889.
Concomitant rock phosphate dissolution and lead immobilization by phosphate solubilizing bacteria (Enterobacter sp.) 总被引:1,自引:0,他引:1
This paper examines the potential value of phosphate solubilizing bacteria (Enterobacter cloacae) in the dissolution of rock phosphate (RP) and subsequent immobilization of lead (Pb) in both bacterial growth medium and soils. Enterobacter sp. showed resistance to Pb and the bacterium solubilized 17.5% of RP in the growth medium. Enterobacter sp. did not enhance Pb immobilization in solution because of acidification of bacterial medium, thereby inhibiting the formation of P-induced Pb precipitation. However, in the case of soil, Enterobacter sp. increased Pb immobilization by 6.98, 25.6 and 32.0% with the RP level of 200, 800 and 1600 mg P/kg, respectively. The immobilization of Pb in Pb-spiked soils was attributed to pyromorphite formation as indicated by XRD analysis. Inoculation of phosphate solubilizing bacteria with RP in soil can be used as an alternative technique to soluble P compounds which can cause eutrophication of surface water. 相似文献
890.
Kensuke Okada William R. Pitchers Manmohan D. Sharma John Hunt David J. Hosken 《Behavioral ecology and sociobiology》2011,65(9):1773-1778
Intraspecific variation in a resting metabolic rate (RMR) is likely to be an important determinant of energetic-resource use
and may influence the resources subsequently available for allocation to traits not directly associated with somatic maintenance.
The influence of RMR on resource availability could be especially important for condition-dependent sexual traits, such as
cricket calls, that are themselves energetically costly to produce. RMR may also be associated with longevity, either negatively
because individuals with a high RMR burn resources faster and die young, or positively as individuals with high RMR are more
able to accrue resources to fuel survival. Additionally, the associations between RMR and other characters may vary across
populations if differential selection or drift shapes these traits. Here we tested for differences in RMR, body mass, calling
effort, and longevity in two populations of cricket Gryllodes sigillatus and then evaluated the potential influence of RMR on calling and longevity. We find that RMR, calling effort, and longevity
varied across populations, but mass did not. Controlling for population and mass, RMR was not significantly associated with
calling effort, but was negatively associated with longevity. These findings suggest that male crickets that live fast die
young. 相似文献