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961.
962.
从电力行业“十一五”期间节能减排工作及其成效来看,现行的以末端治理为主的减排措施很难实现电力行业大气污染物和温室气体的协同减排.本研究构建了大气污染物协同减排当量(APeq)指标,并在此基础上对电力行业技术减排措施和结构减排措施进行成本-效果评价和敏感性分析.结果表明,末端治理措施在削减某一特定污染物的同时,由于耗能增加可导致其它污染物的排放上升;以节能为主的技术减排措施、前端和生产过程控制措施,以及以新发电技术替代为主的结构减排措施可以实现SO2、NOx和CO2的协同减排,且减排潜力较大.此外,本文还在单位(边际)污染减排成本核算与污染减排潜力估算的基础上,绘制出适合中国电力行业的SO2、NOx、CO2和APeq减排路径图,以协助决策者制定适宜的减排规划方案. 相似文献
963.
Response of non-point source pollutant loads to climate change in the Shitoukoumen reservoir catchment 总被引:3,自引:0,他引:3
The impacts of climate change on streamflow and non-point source pollutant loads in the Shitoukoumen reservoir catchment are
predicted by combining a general circulation model (HadCM3) with the Soil and Water Assessment Tool (SWAT) hydrological model.
A statistical downscaling model was used to generate future local scenarios of meteorological variables such as temperature
and precipitation. Then, the downscaled meteorological variables were used as input to the SWAT hydrological model calibrated
and validated with observations, and the corresponding changes of future streamflow and non-point source pollutant loads in
Shitoukoumen reservoir catchment were simulated and analyzed. Results show that daily temperature increases in three future
periods (2010–2039, 2040–2069, and 2070–2099) relative to a baseline of 1961–1990, and the rate of increase is 0.63°C per
decade. Annual precipitation also shows an apparent increase of 11 mm per decade. The calibration and validation results showed
that the SWAT model was able to simulate well the streamflow and non-point source pollutant loads, with a coefficient of determination
of 0.7 and a Nash–Sutcliffe efficiency of about 0.7 for both the calibration and validation periods. The future climate change
has a significant impact on streamflow and non-point source pollutant loads. The annual streamflow shows a fluctuating upward
trend from 2010 to 2099, with an increase rate of 1.1 m3 s−1 per decade, and a significant upward trend in summer, with an increase rate of 1.32 m3 s−1 per decade. The increase in summer contributes the most to the increase of annual load compared with other seasons. The annual
NH4+-N load into Shitoukoumen reservoir shows a significant downward trend with a decrease rate of 40.6 t per decade. The annual
TP load shows an insignificant increasing trend, and its change rate is 3.77 t per decade. The results of this analysis provide
a scientific basis for effective support of decision makers and strategies of adaptation to climate change. 相似文献
964.
965.
966.
单甲脒水中溶解度及正辛醇/水分配系数的测定 总被引:4,自引:5,他引:4
有毒有机化合物在水中的溶解度(WS)及正辛醇/水分配系数(K_(ow)),是描述其在环境中行为的两个重要物理化学参数。本文用溶解度平衡曲线法和振荡法,测得单甲脒在水中的溶解度为21.8±1.3mg/1(25℃),其在正辛醇/水中的分配系数lgK_(ow)为2.92±0.06。 相似文献
967.
968.
Sensitivity of air quality model prediction to parameterization of vertical eddy diffusivity 总被引:1,自引:0,他引:1
This paper investigates the effects of vertical eddy diffusivities derived from the 3 different planetary boundary layer (PBL)
schemes on predictions of chemical components in the troposphere of East Asia. Three PBL schemes were incorporated into a
regional air quality model (RAQM) to represent vertical mixing process and sensitivity simulations were conducted with the
three schemes while other options are identical. At altitudes <2km, all schemes exhibit similar skill for predicting SO2 and O3, but more difference in the predicted NOx concentration. The Gayno–Seaman scheme produces the smallest vertical eddy diffusivity (Kz) among all schemes, leading to
higher SO2 and NOx concentrations near the surface than that from the other 2 schemes. However, the effect of vertical mixing on O3 concentration is complex and varies spatially due to chemistry. The Gayno–Seaman scheme predicts lower O3 concentrations than the other two schemes in the parts of northern China (generally VOC-limited) and higher ones in most
parts of southern China (NOx-limited). The Byun and Dennis scheme produces the largest mixing depth in the daytime, which bring more NOx into upper levels, and the mixing depth predicted by the Gayno–Seaman scheme is the smallest, leading to higher NOx and lower O3 concentrations near the surface over intensive emission regions. 相似文献
969.
外源稀土在土壤中的形态转化研究 总被引:12,自引:0,他引:12
研究了外源可溶性稀土进入土壤后的形态分布及形态转化的时间进程。外源稀土进入土壤(华北潮土)后迅速向各个形态转化,实验进行了60d,稀土形态在此期间的变化结果表明:交换态迅速下降;碳酸盐结合态的变化情况与交换态基本相同,只是下降的幅度较交换态小;铁锰氧化物结合态生微弱地上升,然后逐步下降;有机结合态则先稳定再逐步升高,外源稀土可在此态积累;残渣态在实验期内基本稳定,无明显变化。 相似文献
970.