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251.
The porous carbons derived from cellulose are renewable and environmentally friendly. Coconut shell and wood derived porous carbons were characterized with elemental analysis, ash content, X-ray diffraction, infrared absorbance, particle size, surface area, and pore volume. The results were compared with carbon black. Uniaxial deformation of natural rubber (NR) composites indicate the composites reinforced with the porous carbon from coconut shell have higher tensile moduli at the same elongation ratio than the composites reinforced with wood carbon. 40 % coconut shell composite showed a fivefold increase in tensile modulus compared to NR. Polymer–filler interactions were studied with frequency dependent shear modulus, swelling experiments and dynamic strain sweep experiments. Both linear and non-linear viscoelastic properties indicate the polymer–filler interactions are similar between coconut shell carbon and wood carbon reinforced composites. The swelling experiments, however, showed that the polymer–filler interaction is greater in the composites reinforced with coconut shell instead of wood carbon.  相似文献   
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This paper evaluates the causes of the 23% decline in 2030 US greenhouse gas emissions forecasts between 2007 and 2011. Dynamic regression modeling predicts that the Great Recession contributed to about 67% of the 2008–2009 emissions decline, but then fell to about an 18% share for the 2030 emissions forecast. An analysis of electricity generation forecasts show that switching from coal to gas contributed only 6% to the total 2030 decline. In contrast, regulatory impact assessments and policy analysis showed that state and federal policies were responsible for 46% of the 2030 decline in emissions.  相似文献   
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Abstract

The effects of Thiram and 2 commercial Thiram formulations on the growth and respiration of rhizobia were tested to compare the extent of bacteriostasis under controlled conditions. Although bacteriostasis was measurable at all concentrations tested, liquid cultures grew to maximum optical density in Thiram suspensions containing less than 10 μg/ml. Percentage germination, root elongation, and subsequent nodulation by R. meliloti of 2 cultivars of alfalfa, were determined in thiram suspensions to determine potential physiological effects of the fungicide on the host plant. Conditions were identified which produced enhancement or inhibition of germination, root elongation and development of nodular nitrogenase activity. At concentrations of the fungicide recommended for seed application, only minor, temporary bacteriostasis was observed as a possible negative effect while germination rates of fungi‐contaminated seed were markedly increased.  相似文献   
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A short-term study to characterize the solid waste stream in the Municipality of Veles, Macedonia, was performed during a 1 week period in the summer of 2002. In this study, several important parameters of the municipal solid waste stream were assessed. It was estimated that the average daily generation rate is 1.06+/-0.56 kg/cap/day, while the specific weights of the uncompacted and compacted solid waste are approximately 140.5 kg/m3 and 223 kg/m3, respectively. Furthermore, it was estimated that the daily generated volume of uncompacted waste is 7.5+/-4 L/cap/day. Although the short-term study is characterized by numerous limitations, in the absence of other existing data, such a study with direct measurements could significantly contribute to the development of an efficient solid waste management system in countries with economies in transition like Macedonia.  相似文献   
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