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排序方式: 共有1581条查询结果,搜索用时 12 毫秒
41.
Chi Zhang P.R. Shukla David G. Victor Thomas C. Heller Debashish Biswas Tirthankar Nag 《Energy Policy》2006
The study examines the dynamics of carbon emissions baselines of electricity generation in Indian states and Chinese provinces in the backdrop of ongoing electricity sector reforms in these countries. Two Indian states—Gujarat and Andhra Pradesh, and three Chinese provinces–Guangdong, Liaoning and Hubei have been chosen for detailed analysis to bring out regional variations that are not captured in aggregate country studies. The study finds that fuel mix is the main driver behind the trends exhibited by the carbon baselines in these five cases. The cases confirm that opportunities exist in the Indian and Chinese electricity sectors to lower carbon intensity mainly in the substitution of other fuels for coal and, to a lesser extent, adoption of more efficient and advanced coal-fired generation technology. Overall, the findings suggest that the electricity sectors in India and China are becoming friendlier to the global environment. Disaggregated analysis, detailed and careful industry analysis is essential to establishing a power sector carbon emissions baseline as a reference for CDM crediting. However, considering all the difficulties associated with the baseline issue, our case studies demonstrate that there is merit in examining alternate approaches that rely on more aggregated baselines. 相似文献
42.
Evaluation of projection algorithms 总被引:1,自引:0,他引:1
Biswas G Jain AK Dubes RC 《IEEE transactions on pattern analysis and machine intelligence》1981,(6):701-708
A number of linear and nonlinear mapping algorithms for the projection of patterns from a high-dimensional space to two dimensions are available. These two-dimensional representations allow quick visual observation of a data set. A combination of two popular mapping algorithms-Sammon's mean-square error technique and the triangulation method-is proposed to overcome the limitations in the individual algorithms. Some factors which describe the goodness of a projection are described, and a comparison is made of six of these algorithms by running them on four data sets. The results obtained support the use of the proposed algorithm. 相似文献
43.
Erivan de Souza Oliveira Mighay Lovera Valessa Rios Pires Francisco Rogênio da Silva Mendes Nadya Virginia Lima Peixoto Maia João Pedro Viana Rodrigues Maria do Socorro Rocha Bastos Huai N. Cheng Atanu Biswas Renato de Azevedo Moreira Ana Cristina de Oliveira Monteiro Moreira 《Journal of Food Processing and Preservation》2022,46(3):e16408
44.
David G. Stevenson George E. Inglett Diejun Chen Atanu Biswas Fred J. Eller Roque L. Evangelista 《Food chemistry》2008
Oat bran concentrate (OBC) was defatted with supercritical carbon dioxide (SCD), then microwave-irradiated (MI) at 50, 100 or 150 °C for 10 min in water, 50% or 100% ethanol, and extract pH, soluble solids, phenolic content (PC) and antioxidant capacity (AC) were analysed. OBC was air-classified into five fractions and MI in water at 150 °C. OBC without SCD and microwave irradiation was extracted at 22 °C. Most effective temperature during microwave irradiation for maximising extraction of PC and AC was 150 °C. Defatted OBC in 50% ethanol and MI at 150 °C extracted greatest PC and AC. SCD treatment slightly reduced PC and AC. OBC extracted in water or 50% ethanol at 22 °C without microwave irradiation had similar PC and AC than OBC MI at 150 °C, but much higher levels were observed for latter heat treatment using absolute ethanol. Air-classification shows potential to enhance PC and AC. 相似文献
45.
Asit K. Biswas 《国际水资源开发杂志》1984,2(1):3-25
Monitoring and evaluation of irrigation projects has been a neglected subject in the past. While some lip service has been given to this subject, with few exceptions, it has received very little attention or consideration as a part of the overall management process for the projects. It is argued that without a continuing and effective monitoring and evaluation system, it is unlikely that the project benefits can be achieved or they will be optimal. A comprehensive monitoring and evaluation system is recommended for irrigation projects at four interrelated levels: planning, design and construction of physical facilities; operation and maintenance of irrigation and drainage facilities; agricultural production and achievement of socio‐economic objectives. 相似文献
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The study deals with the vulcanization of carboxylated nitrile butadiene rubber (XNBR) having synergistic combinations of accelerators comprising thiophosphoryl disulfide as one of the components. Other constituent accelerators employed in the present investigation are 2-mercaptobenzothiazole (MBT), 2-mercaptobenzothiazyl disulfide (MBTS), bis(N-oxydiethylene)disulfide (ODDS), N-oxydiethylene 2-benzothiazole sulfenamide (OBTS), etc. The binary combinations of thiophosphoryl disulfides with OBTS exhibited the highest mutual activity in the respective areas, so far as the physical properties are concerned. Structural characterization of different thiophosphoryl disulfide-accelerated XNBR vulcanizates, including those formed from the synergistic combinations with OBTS, were studied using a methyl iodide probe. It was found that the amount of sulfidic crosslinks arising from the reaction between COOH groups of XNBR and thiophosphoryl disulfides, actually controls the network structure as wellas the physical properties of the vulcanizates. © 1996 John Wiley & Sons, Inc. 相似文献
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Poly(N-vinyl carbazole) was sulfonated with different sulfonating agents and ion exchange capacities of the resins produced were evaluated. A maximum capacity of 4.5 meq · g?1 of dry resin was realized when sulfonation was done with 98.8% H2SO4 at 30°C for 10 h. The pH titration curves reveal the nature of a strong monofunctional cation exchanger with a pK value of 2.2. The resin exhibits a moderate rate of exchange with NaCl and is thermally stable up to ca. 250°C. 相似文献
50.
A crosslinked polymer has been synthesized from the reaction of N-vinylcarbazole and formalin in toluene in the presence of dry HCl gas. The copolycondensate is insoluble in all common solvents for poly-N-vinylcarbazole, and exhibits higher thermal stability than the unmodified poly-N-vinylcarbazole. However, this polymer is less thermally stable than the corresponding furfural modified poly-N-vinylcarbazole. A mechanism for the overall reaction has been suggested and the factors affecting the synthesis have been discussed. 相似文献