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91.
Scott Murtishaw Jayant Sathaye Christina Galitsky Kristel Dorion 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):645-665
The Lawrence Berkeley National Laboratory (Berkeley Lab) and the Center for Sustainable Development in the Americas (CSDA)
conducted technical studies and organized two training workshops to develop capacity in Central America for the evaluation
of climate change projects. This paper describes the results of two baseline case studies conducted for these workshops, one
for the power sector and one for the cement industry, that were devised to illustrate certain approaches to baseline setting.
Multiproject baseline emission rates (BERs) for the main Guatemalan electricity grid were calculated from 2001 data. In recent
years, the Guatemalan power sector has experienced rapid growth; thus, a sufficient number of new plants have been built to
estimate viable BERs. We found that BERs for baseload plants offsetting additional baseload capacity ranged from 0.702 kgCO2/kWh
(using a weighted average stringency) to 0.507 kgCO2/kWh (using a 10th percentile stringency), while the baseline for plants
offsetting load-following capacity is lower at 0.567 kgCO2/kWh. For power displaced from existing load-following plants, the
rate is higher, 0.735 kgCO2/kWh, as a result of the age of some plants used for meeting peak loads and the infrequency of
their use. The approved consolidated methodology for the Clean Development Mechanism yields a single rate of 0.753 kgCO2/kWh.
Due to the relatively small number of cement plants in the region and the regional nature of the cement market, all of Central
America was chosen as the geographic boundary for setting cement industry BERs. Unfortunately, actual operations and output
data were unobtainable for most of the plants in the region, and many data were estimated. Cement industry BERs ranged from
205 kgCO2 to 225 kgCO2 per metric ton of cement. 相似文献
92.
WAHG Ren-zhong 《环境科学学报(英文版)》2002,14(1):20-26
Population demography, seed production, biomassallocation, net photosynthesis and transpiration of two Leymus chinensis divergence populations and between two years in Songnenplain, northeast China were compared. Strong differences betweenthe dry 1997 and moist 1998 occurred in vegetative shoot and sexualshoot densities, sexual differentiation and tiller densities, aswell as in the lengths of inflorescence, seed numbers perinflorescence, seed weights and biomass allocation in eachpopulation respectively (P<0.01). While strong differences betweenthe two populations occurred in vegetative shoot densities, sexualshoot densities, sexual differentiation and seed weights in eachyear (P<0.01). The differences between the two populations intiller densities and in biomass allocation to sexual shoots were significant (P<0.05). But there were no significant differences between the two populations in the lengths of inflorescence, seed numbers per inflorescence and biomass allocation to rhizomes and vegetative shoots (P>0.05). Excepting the transpiration rate in the early June, the differences between the two populations in net photosynthesis and transpiration rate of vegetative shoots and sexual shoots were strongly significant in the early June and July respectively (P<0.01). Relative stable variations in population demography and physiological traits between the two populations indicated that they are divergently in the Songnen Plain. 相似文献
93.
草浆造纸中段废水的生物处理动力学 总被引:1,自引:0,他引:1
利用静态溶解氧消耗速率(OUR)试验模拟草浆造纸中段废水生物处理的生化反应过程,并运用Lawrence-McCarty模式进行了动力学分析。由OUR试验结果和小试研究结果建立的草浆造纸中段废水好氧生物处理的动力学方程为v=0.72S/(60.43 S)。将该动力学方程预测结果和实际工程的运行数据进行了比较,结果表明,动力学方程的比基质降解速率预测值高于实际工程的计算值,分析原因可能在于:实际工程中中段废水中的纤维素类悬溪物在生物处理装置的积累导致了污泥活性的降低。 相似文献
94.
95.
西湖底泥不同供氧条件下有机质降解及CO2与CH4释放速率的模拟研究 总被引:15,自引:0,他引:15
采用密闭培养实验装置于室温(25℃左右)及pH为75条件下,对西湖底泥中有机质完全降解及转化为CO2和CH4的速率进行了模拟研究.结果表明,在西湖湖水现有供氧水平(50—86mg(O2)/L)条件下,底泥中有机质完全降解的速率最为缓慢,培养期间(42天)平均只有072mg(C)/(kg·d).当湖水供氧水平进一步上升(86→120→160mg(O2)/L),CO2释放速率增加,最大值可达到87mg(C)/(kg·周);当湖水供氧水平下降(86→0mg(O2)/L),CH4释放速率加快,最大值可达到46mg(C)/(kg·周). 相似文献
96.
LAO Shan-gen 《环境科学学报(英文版)》2002,14(1):132-135
IntroductionBeforethe 1 980sconventionaltreatmentprocessesofphenolswastewateraresolventextraction ,physicaladsorption ,chemicaloxidationandaerobicbiologicalprocess.Amongthebiologicalunitprocessesactivatedsludgeprocessismainone.Afterthe 1 980sanaerobicbiologic… 相似文献
97.
本文介绍了用碱式聚合氯化铝处理高浓度有机淀粉废水的效果。用实验室配制的CODw浓度为10000-15000mg/L的淀粉废水以不同用量的碱式聚合氯化铝为絮凝剂处理后,CODw去除率达到28%-47%,再经吸附柱吸附后,CODw去除率可达到65%。 相似文献
98.
GametheoryapproachtooptimalcapitalcostalocationinpolutioncontrolChenWenyingInstituteofNuclearEnergyTechnology,TsinghuaUniver... 相似文献
99.
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