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971.
通过对山东电网所属发电厂锅炉NOx排放状况进行调查、测试,得出锅炉NOx排放量与煤种、炉型、燃烧器型式、运行中空气过剩系数、负荷等的关系.结果表明,山东省火力发电厂50 MW及以上容量机组2003年的NOx排放总量超过40万t(按NO2计算).控制和治理NOx排放已成为刻不容缓的重要工作.  相似文献   
972.
Signalized intersections have been identified as vehicle emission hotspots, where drivers decelerate, idle, and accelerate their vehicles in response to signal changes. Advanced traffic signal status warning systems (ATSSWSs) can be applied to reduce traffic emissions at intersections by mitigating unnecessary braking and acceleration. In this study, two types of ATSSWSs, variable message sign (VMS) based and vehicle-to-infrastructure (V2I) based, were designed, and their environmental effectiveness was evaluated through driving simulator-based experiments. Three scenarios were designed and tested: (1) baseline without an ATSSWS, (2) with the VMS-based ATSSWS, and (3) with the V2I-based ATSSWS. The Motor Vehicle Emission Simulator model was used to evaluate and compare the environmental effectiveness of these two types of ATSSWSs. The results indicate that the proposed ATSSWSs can reduce traffic emissions at signalized intersections. In particular, the V2I-based ATSSWS can substantially reduce CO2, NOx, CO, and HC emissions. The results will help transportation practitioners with implementing advanced driver information systems and decision making on emission reduction policies.

Implications: Signalized intersection has been identified as one of hottest spots for vehicle emissions where signal control causes vehicles to frequently decelerate, idle, and accelerate. Advanced Traffic Signal Status Warning Systems (ATSSWS) can be applied to reduce traffic emission at intersections by decreasing vehicles’ unnecessary brakes and accelerations. The results of this study will assist transportation practitioners in implementing advanced driver information systems and making decisions on emission reduction policies.  相似文献   

973.
Jiang Z  Yang H  Sun L  Shi S 《Chemosphere》2002,48(1):133-138
In this paper, the amount of oxygen consumption, end products and activities of microorganisms are considered as the three factors which affect the biodegradability of organic substances in water. Two integrated assessment methods for biodegradability of organic substances, fuzzy clustering integrated assessment and weighted integrated assessment, have been developed. Simultaneously, the detail steps for assessing a new organic substance biodegradability with these two integrated assessment methods are proposed.  相似文献   
974.
催化湿式氧化处理机械加工工业废水的研究   总被引:5,自引:0,他引:5  
利用担载的双金属活性组分催化剂,考察了反应温度、压力、进料空速和污水pH等条件对催化湿式氧化处理某厂机械加工废水效果的影响。对于该厂的混合废水,在反应温度260℃,反应压力6.6MPa,空速为2.0h^-1,pH为3条件下处理后的废水CODCr去除率为90.2%。考察了助剂H2O2、絮凝剂对处理废水效果的影响和各种联用技术对废水的处理效果。  相似文献   
975.
磁粉强化活性污泥法处理餐饮废水的研究   总被引:17,自引:0,他引:17  
磁粉强化活性污泥化是在常规活性污泥法中加入适量强磁性粉末的废水生物处理方法。研究了用磁粉活性污泥法净化处理餐饮废水,通过与普通活性污泥法的平行试验,结果表明,磁粉强化活性污泥法适宜的磁粉加入量为700mg/L儿,磁粉粒度<1μm,CODcr去除率和出水透光率都优于普通活性污泥法,活性污泥氮体结构和沉降性能明显改善。  相似文献   
976.
Florig HK  Sun G  Song G 《Chemosphere》2002,49(9):1163-1174
China's urban and rural populations face very serious health risks from combustion particles. Major sources of exposure to inhalable particulates include the burning solid fuels (biomass and coal) for household cooking and heating, coal-fired industrial and residential boilers, tobacco smoking, and diesel motor vehicles. China began to address particulate pollution problems over 25 years ago and has implemented a series of progressively more aggressive policies. This paper reviews the successes and limitations of past and existing policies for particulate controls, as well as the effects of China's economic reforms and energy policies on particulate exposure and pollution management. We examine the challenge of emissions reporting, required as part of both China's pollution levy system and emerging system for "total emissions control." Finally, we discuss practical steps toward exposure-based regulation of particulates, which would take advantage of the high cost-effectiveness for lifesaving of controlling particulate exposure from household and neighborhood sources relative to that of controlling exposure from industrial sources.  相似文献   
977.
Sun H  Xu J  Yang S  Liu G  Dai S 《Chemosphere》2004,54(4):569-574
Experiments were conducted to investigate the degradation of aldicarb, an oxime carbamate insecticide, in sterile, non-sterile and plant-grown soils, and the capability of different plant species to accumulate the pesticide. The degradation of aldicarb in soil followed first-order kinetics. Half lives (t1/2) of aldicarb in sterile and non-sterile soil were 12.0 and 2.7 days, respectively, which indicated that microorganisms played an important part in the degradation of aldicarb in soil. Aldicarb disappeared more quickly (p< or =0.05) in the soil with the presence of plants, and t1/2 of the pesticide were 1.6, 1.4 and 1.7 days in the soil grown with corn, mung bean and cowpea, respectively. Comparison of plant-promoted degradation and plant uptake showed that the enhanced removal of aldicarb in plant-grown soil was mainly due to plant-promoted degradation in the rhizosphere.  相似文献   
978.
就油田含油固体废弃物的存放及其对周边环境存在的潜在隐患 ,全面分析了该废弃物的组成与成分 ,并介绍了几种可用于石油污染土壤治理技术的方法特点 ,尤其是针对这种固体含量和油分含量皆较高的含油固体废弃物 ,开展了综合利用治理技术方面的试验 ,以固体废弃物细粉作为制砖助燃配料成分 ,考查了砖块质量与细粉掺入量及其他因素之间的关系 ,取得了较好的效果  相似文献   
979.
回顾了我国在富营养化湖泊底泥污染控制技术方面的研究进展,并从富营养化湖泊底泥污染控制技术的运用效果、环境影响、社会影响、经济性、适用性以及与其他技术的相关性等六个方面,全面评估了破坏分层、人工曝气、化学增氧、底泥疏浚和底泥封闭等五类技术.  相似文献   
980.
Knowledge of the factors that influence the fate and transport of viruses in porous media is very important for accurately determining groundwater vulnerability and for developing protective regulations. In this study, six saturated sand column experiments were performed to examine the effects of a positively charged Al-oxide, which was coated on sand particles, on the retention and transport of viruses (phiX174 and MS-2) in background solutions of different ionic strength and composition. We found that the Al-oxide coating on sand significantly removed viruses during their transport in a phosphate buffered saline (PBS) solution. Mass balance calculations showed that 34% of the input MS-2 was inactivated/irreversibly sorbed on the surface of Al-oxide coated sand whereas 100% of phiX174 was recovered. Results from this study also indicated that higher ionic strength facilitated the transport of both phiX174 and MS-2 through the Al-oxide coated sand. This was attributed to the effect of ion shielding, which at higher ionic strength decreased the electrostatic attraction between the viral particles and the sand surface and consequently decreased virus sorption. Strong effect of the ionic strength indicates that an outer-sphere complexation mechanism was responsible for the virus sorption on the Al-oxide coated sand. Ion composition of the background solutions was also found to be a significant factor in influencing virus retention and transport. Virus transport was enhanced in the presence of phosphate (HPO(4)(2-)) as compared to bicarbonate (HCO(3)(-)), and the effect of HPO(4)(2-) was more significant on MS-2 than on phiX174. The presence of bivalent cations (Ca(2+) and Mg(2+)) increased virus transport because the cations partially screened the negative charges on the viruses therefore decreased the electrostatic attraction between the positively charged sand surface and the negatively charged viruses. Mass recovery data indicated that bivalent cations gave rise to a certain degree of inactivation/irreversibly sorption of phiX174 on the surface of Al-oxide coated sand. On the contrary, the bivalent cations appeared to have protected MS-2 from inactivation/irreversibly sorption. This study provides some insights into the mechanisms responsible for virus retention and transport in porous media.  相似文献   
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