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1.
Sathaye  J.A.  Makundi  W.R.  Andrasko  K.  Boer  R.  Ravindranath  N.H.  Sudha  P.  Rao  S.  Lasco  R.  Pulhin  F.  Masera  O.  Ceron  A.  Ordonez  J.  Deying  X.  Zhang  X.  Zuomin  S. 《Mitigation and Adaptation Strategies for Global Change》2001,6(3-4):185-211
This paper summarizes studies of carbon (C) mitigation potential and costs of about 40 forestry options in seven developing countries. Each study uses the same methodological approach – Comprehensive Mitigation Assessment Process (COMAP) – to estimate the above parameters between 2000 and 2030. The approach requires the projection of baseline and mitigation land-use scenarios. Coupled with data on a per ha basis on C sequestration or avoidance, and costs and benefits, it allows the estimation of monetary benefit per Mg C, and the total costs and carbon potential. The results show that about half (3.0 Pg C) the cumulative mitigation potential of 6.2 Petagram (Pg) C between 2000 and 2030 in the seven countries (about 200× 106 Mg C yr-1) could be achieved at a negative cost and the remainder at costs ranging up to $100 Mg C-1. About 5 Pg C could be achieved, at a cost less than $20 per Mg C. Negative cost potential indicates that non-carbon revenue is sufficient to offset direct costs of these options. The achievable potential is likely to be smaller, however, due to market, institutional, and sociocultural barriers that can delay or prevent the implementation of the analyzed options.  相似文献   
2.
For developing countries, the proportion of households covered by improved water resources is conventionally used to assess the water stress situation. However, in a developing country like India with a high population growth rate, water demand and supply are considerably mismatched. An agro-based economy with large variations in socio-economic conditions and changing rainfall patterns across the states imposes greater challenge on water resources. Therefore, there is a need to assess the water situation across the country in a holistic manner. This paper proposes application of the Water Poverty Index as a comprehensive policy tool to assess actual water-stress situation across 20 major states in India. This index covers important socio-economic parameters such as access, capacity, use and environment in addition to water resources of each state. The results and findings are expected to be of use to policymakers and implementing agencies. In view of policy formulation, a state performing well on a Water Poverty Index component can act as a benchmark for another state.  相似文献   
3.
The photochemical fate of seven sulfonamides was investigated in matrices representative of natural water bodies under various light sources. Fundamental photolysis parameters such as molar absorption coefficient, quantum yield (QY) and first-order rate constants were determined. The photolysis decay rate was dependent on the protonation state of the molecule, pH of the water sample and dissolved organic matter. Natural organic matter was the most significant factor in the indirect photolysis of sulfonamides. Half-lives were in the range of minutes at 254 nm to days under natural sunlight. Under natural sunlight, all sulfonamides showed higher removal rates in natural waters implying that indirect photolysis is the predominant mechanism.  相似文献   
4.
The influence of clay on the adsorption of heavy metals like copper and cadmium on chitosan from simulated industrial wastewater is evaluated. Chitosan–clay blend with ratio of (1:1), (1:2), and (2:1) have been prepared, and these were used as membranes to remove copper and cadmium ions from synthetic industrial wastewater. The chemical parameters for quantities of adsorption of heavy metal contamination have been done, and the kinetics of adsorption has also been carried out. Clay provides enough absorbable sites to overcome mass transfer limitations. The number of absorbable sites for cadmium is more compared to copper, and thus the rate of recovery of cadmium is faster than copper, and the percentage removal of cadmium is more than copper at all times on clay over nylon 6. This difference indicates the influence of clay in the adsorption of heavy metals in comparison to synthetic polymer nylon 6. Rate constant for first-order kinetics of adsorption, k 1, for copper and cadmium is less than that of clay, which clearly indicates that clay, which is a natural polymer, is more kinetically favored compared to synthetic polymer. The difference in the intraparticle diffusion in both the natural and synthetic polymer is not much, and it suggests that the particle diffusion mechanism is the same in both cases. Copper and cadmium recovery is parallel at all times. The percentage of removal of copper increased with an increase in pH from 3 to 5. In the case of cadmium containing wastewater, the maximum removal of metal occurred at pH 5. The uptake amount of Cu2+ ions on chitosan increased rapidly with increasing the contact time from 0 to 360 min and then reaches equilibrium after 360 min, and the equilibrium constant for copper and cadmium ions are more or less the same for the adsorption reaction. There are more adsorption sites for cadmium in the presence of clay and mass transfer limitation is avoided without resorting to rotation, which is the highlight of the present work. And more so, this is pronounced in the case of natural polymer compared to synthetic polymer.  相似文献   
5.
Summary. Benzoic acid is a known stimulant of olfactory receptor cells in trichoid sensilla on the antennae of adult females of Bombyx mori. Exposure of freshly excised antennae, from B. mori females and males, to vapours of [14C]-benzoic acid revealed that the adsorbed acid is rapidly metabolized (15% conversion in 10 s), suggesting the presence of a highly active enzymatic system. The major product could be identified as N-benzoylserine by use of [2H5]-benzoic acid, and mass spectrometry linked to a gas chromatograph (GC-MS) or a liquid chromatograph (LC-MS), for analysis of the metabolites. The conjugation of benzoic acid with an amino acid apparently represents a novel mode for the rapid deactivation of odorant molecules. Received 26 March 2001.  相似文献   
6.
Polyphenols of natural and synthetic origin are exploited in tanning sector to convert putrescible skin/hide to non-putrescible leather. However, only 30-40% of the inputs have been taken up for processing, the remaining is released as unspent. The existing conventional wastewater treatment systems are inefficient in removing or degrading these unspent polyphenols and thus detrimental to ecosystem. The present study demonstrates the evaluation of impact of both synthetic and natural polyphenols on biochemical and haematological properties of blood and serum in animal models. The results reveal that concentrations of polyphenols play a major role. At higher concentrations, irrespective of their nature, there was a marked change in the lipid profile (81% reduction), followed by insignificant change in glucose levels, RBC and WBC counts and other haematological parameters. At lower concentrations, no significant changes in the above said properties were observed.  相似文献   
7.
This paper presents an overview of current solid waste management (SWM) practices in Kolkata, India and suggests solutions to some of the major problems. More than 2920ton/d of solid waste are generated in the Kolkata Municipal Corporation (KMC) area and the budget allocation for 2007-2008 was Rs. 1590 million (US$40 million), which amounts to Rs. 265/cap-y (US$6.7/cap-d) on SWM. This expenditure is insufficient to provide adequate SWM services. Major deficiencies were found in all elements of SWM. Despite 70% of the SWM budget being allocated for collection, collection efficiency is around 60-70% for the registered residents and less than 20% for unregistered residents (slum dwellers). The collection process is deficient in terms of manpower and vehicle availability. Bin capacity provided is adequate but locations were found to be inappropriate, thus contributing to the inefficiency of the system. At this time, no treatment is provided to the waste and waste is dumped on open land at Dhapa after collection. Lack of suitable facilities (equipment and infrastructure) and underestimates of waste generation rates, inadequate management and technical skills, improper bin collection, and route planning are responsible for poor collection and transportation of municipal solid wastes.  相似文献   
8.
Mesoporous carbon adsorbents, having high nitrogen content, were synthesized via nanocasting technique with melamine–formaldehyde resin as precursor and mesoporous silica as template. A series of adsorbents were prepared by varying the carbonization temperature from 400 to 700°C. Adsorbents were characterized thoroughly by nitrogen sorption, X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), thermogravimetric analysis(TGA), elemental(CHN) analysis, Fourier transform infrared(FTIR) spectroscopy and Boehm titration. Carbonization temperature controlled the properties of the synthesized adsorbents ranging from surface area to their nitrogen content, which play major role in their application as adsorbents for CO_2 capture.The nanostructure of these materials was confirmed by XRD and TEM. Their nitrogen content decreased with an increase in carbonization temperature while other properties like surface area, pore volume, thermal stability and surface basicity increased with the carbonization temperature. These materials were evaluated for CO_2 adsorption by fixed-bed column adsorption experiments. Adsorbent synthesized at 700°C was found to have the highest surface area and surface basicity along with maximum CO_2 adsorption capacity among the synthesized adsorbents. Breakthrough time and CO_2 equilibrium adsorption capacity were investigated from the breakthrough curves and were found to decrease with increase in adsorption temperature. Adsorption process for carbon adsorbent–CO_2 system was found to be reversible with stable adsorption capacity over four consecutive adsorption–desorption cycles. From three isotherm models used to analyze the equilibrium data, Temkin isotherm model presented a nearly perfect fit implying the heterogeneous adsorbent surface.  相似文献   
9.
Based on the Institutional Collective Action framework, this research tests the impact of two competing hypotheses—bonding and bridging—on enhancing organisational resiliency. The bonding hypothesis posits that organisational resiliency can be achieved if an organisation works closely with others, whereas the bridging hypothesis argues that such a structure places considerable stress on an organisation and advocates for an organisation to position itself as a central actor to gain access to novel resources from a diverse set of entities to achieve resiliency. The paper analyses data gathered from semi‐structured interviews with 44 public, private, and non‐profit organisations serving communities affected by the Great Floods of 2011 in the Thai capital, Bangkok (urban), and in Pathum Thani (suburban) and Ayutthaya (rural) provinces. The findings suggest that: organisational resiliency was associated with the bridging effect; organisations in the rural province were more resilient than those in the suburban and urban centres; and private and non‐governmental organisations generally were more resilient than public sector organisations. The findings highlight the importance of fostering multi‐sector partnerships to enhance organisational resiliency for disaster response.  相似文献   
10.
The hyper-eutrophicated Krishnagiri reservoir is situated in hot tropical and semiarid climate zone in South India. There are 16 villages in the command area, which are directly benefited by this reservoir, and water from the reservoir is used for irrigation, fish rearing, livestock rearing and recreation purposes. The reservoir is located in an agricultural watershed, and the rate of soil erosion in the catchment area is very high. Thus, the reservoir is severely affected by sedimentation, and half of its capacity was reduced. Previous studies in Krishnagiri reservoir clearly indicate the lack of information on the quality of sediments and dynamics of nutrient in the reservoir. Hence, the present study was conducted on bottom sediments, and it included the assessment of physicochemical characteristics and nutrients, such as composition, redox potential, moisture content, organic carbon, organic matter, total iron, manganese, calcium carbonate, different phosphorus fractions and total phosphorus. The increasing trend in organic matter and also the significant change from positive to high negative values of redox potential clearly indicate the inflow of high organic load which may result from the disposal of sewage and industrial waste water in the upstream catchment side. The high concentration of inorganic phosphorus fractions at the inflow point of the reservoir obviously implies that there was a significant input of nutrients into the reservoir. Hence, the study concludes that the rainfall, soil erosion and runoff are the major environmental factors for the input and accumulation of large quantities of nutrients in the bottom sediments of Krishnagiri reservoir during the study period. The present study clearly suggests for a careful investigation into sediment nutrients in Krishnagiri reservoir, and it is also necessary to assess the role of sediments in the phosphorus dynamics and its significant effect on eutrophication. This study demonstrates that the examination of physicochemical characteristics and nutrients in the bottom sediments is a helpful tool to identify the sources of nutrients to the reservoir. The baseline data provided in this paper will be helpful for the policy makers to frame better policies for the sustainable management of water quality in Krishnagiri reservoir.  相似文献   
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