The study for polyaromatic hydrocarbons decay on Chinese coal soot particles in atmosphere

A study for the photochemical behavior of some polyaromatic hydrocarbons (PAH), for example B(a )P, B( k )F and fluoranthene in coal smoke particles was performed by using indoor Teflon smog chamber.Experiments suggest that the photochemical reaction of PAH is first order reaction and kinetic rates of some PAH were obtained. It was shown that the reaction rate constant is proportional to light intensity and water vapor concentration. Temperature and PAH loading also have influence on PAH decay rate. A model for PAH loss has been set up on the basis of the results of our experiments and the simulating results of this model suggest that coal particle PAH half lives are of the order of a period of days in winter and a few hours in summer. Other factors which may have effect on the photochemical reaction of PAH have also been discussed.     

层燃—流化床焚烧城市垃圾技术

首次提出的层燃－流化床燃烧技术是适合我国国情的城市垃圾处理技术，可使预处理过程达到最简化并保证燃烧过程的稳定必和彻底性，给出了层燃－流化床双床焚烧炉的结构和工作原理。     

环境经济优化设计案例

本文列举三例，论述完善价格机制发展城市燃气供应事业、运用排污权交易思想削减二氧化硫污染和利用市场干预促进固体废弃物回收，分别设计出优化方案，并概算出预期环境经济效益。     

Methodological and Practical Considerations for Developing Multiproject Baselines for Electric Power and Cement Industry Projects in Central America

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.     

燃煤烟气脱硫技术分析

介绍了国内目前正在使用或即将使用的燃煤烟气脱硫技术的工艺特点、操作参数和适用范围。这些技术包括湿式石灰石(石灰)-石膏法、炉内喷钙后部烟气增湿脱硫法、海水洗涤法、除尘脱硫一体化技术等。     

简述日本降低燃煤锅炉NOX产生的实用技术

简要介绍了日本降低燃煤锅炉ＮＯＸ产生的实用技术，从ＮＯＸ的产生机制入手，以抑制ＮＯＸ的产生为目的，叙述了改善燃烧方法及改善燃烧器的原理，模式图及实用现状。     

NATURAL EROSION RATES AND THEIR PREDICTION IN THE IDAHO BATHOLITH1

ABSTRACT: Natural rates of surface erosion on forested granitic soils in central Idaho were measured in 40 m² bordered erosion plots over a period of four years. In addition, we measured a variety of site variables, soil properties, and summer rainstorm intensities in order to relate erosion rates to site attributes. Median winter erosion rates are approximately twice summer period rates, however mean summer rates are nearly twice winter rates because of infrequent high erosion caused by summer rainstorms. Regression equation models and regression tree models were constructed to explore relationships between erosion and factors that control erosion rates. Ground cover is the single factor that has the greatest influence on erosion rates during both summer and winter periods. Rainstorm intensity (erosivity index) strongly influences summer erosion rates, even on soils with high ground cover percentages. Few summer storms were of sufficient duration and intensity to cause rilling on the plots, and the data set was too small to elucidate differences in rill vs. interrill erosion. The regression tree models are relatively less biased than the regression equations developed, and explained 70 and 84 percent of the variability in summer and winter erosion rates, respectively.     

我国燃煤电厂脱硫技术应用现状及展望

介绍了我国二氧化硫排放及污染现状，分别从燃烧前、燃烧中、燃烧后三个阶段，阐述了我国脱硫煤生产、低硫污染燃烧技术及燃煤烟气脱硫的污染控制技术现状和发展方向，提出我国控制燃煤硫污染的对策及建议。     

燃煤锅炉脱硫工艺浅谈

简述了燃煤锅炉常用烟气脱硫方法和烟气脱硫工艺选择原则，介绍一种简易脱硫工艺。     

How certain are we about the certainty-equivalent long term social discount rate?

Theoretical arguments for using a term structure of social discount rates (SDR) that declines with the time horizon have influenced government guidelines in the US and Europe. The certainty equivalent discount rate that often underpins this guidance embodies uncertainty in the primitives of the SDR, such as growth. For distant time horizons the probability distributions of these primitives are ambiguous and the certainty equivalent itself is uncertain. Yet, if a limited set of characteristics of the unknown probability distributions can be agreed upon, ‘sharp’ upper and lower bounds can be defined for the certainty-equivalent SDR. Unfortunately, even with considerable agreement on these features, these bounds are widely spread for horizons beyond 75 years. So while estimates of the present value of intergenerational impacts, including the social cost of carbon, can be bounded in the presence of this ambiguity, they typically remain so imprecise as to provide little practical guidance.