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81.
车辆通过交叉口的生态驾驶轨迹优化研究   总被引:1,自引:0,他引:1  
车辆在道路交叉口经常出现启停和怠速现象,交叉口成为了道路交通网络中高能耗高排放的重要区域.因此需要对车辆通过交叉口的生态驾驶轨迹进行优化研究.首先将当前信号状态分为六种情景,利用数学模型对不同情景下车辆通过交叉口的驾驶轨迹进行定量表达;然后将交叉口上游和下游整体考虑,针对各情景建立了生态驾驶策略模型和生态驾驶轨迹优化算法;最后假定情景并设定参数,利用MATLAB开发程序,结合基于机动车比功率参数的排放量化模型,对各驾驶轨迹的排放进行仿真模拟.模拟结果表明:构建的生态驾驶轨迹优化算法,可使车辆CO2、NOx、CO、HC4种排放物分别降低30.1%、23.6%、24.9%、21.5%,可为面向生态的驾驶辅助系统开发提供应用算法.  相似文献   
82.
中国的对口支援对灾后重建具有重要意义。但各支援方应支付多少?按照何种标准进行援助?鲜有相关研究。所以应考虑灾害给支援方带来的间接经济损失等因素。通过构建支援金额与间接经济损失之比的指标,评价了汶川8.0级地震中各支援省市的对口支援行为。结果表明:北京、福建、江西、山东、上海等省市的支援额"过多",黑龙江、天津、河南、重庆、河北等省市的支援额"过少",均有失公平。还以2013年发生的芦山7.0级地震为例,就各省市的对口支援额给出了建议值。最后就如何完善对口支援政策提出了相应的建议。  相似文献   
83.
城市生态文明建设评价指标体系构建   总被引:1,自引:1,他引:0  
城市作为人类环境问题和危机产生的重要策源地,建立反映城市生态环境问题和生态文明建设状态的评价指标体系,依据评价结论,指导城市生态文明建设十分必要。文章在城市作为社会—经济—自然复合人工生态系统的理论基础上,分析了社会生态亚系统、经济生态亚系统及自然生态亚系统相互作用关系和城市生态系统主要生物成分组成、结构与功能关系,系统的构建了符合中国国情的城市生态文明评价指标体系。该体系以生态经济、生态环境质量、生态社会为评价要素,下设12个一级指标及42个二级指标,为评价中国城市生态文明建设水平提供科学依据。  相似文献   
84.
The UASB system successfully treated sulfamethoxazole pharmaceutical wastewater. High concentration sulfate of this wastewater was the main refractory factor. UASB recovery performance after a few days of inflow arrest was studied. The optimal UASB operating conditions for practical application were determined. Treatment of sulfamethoxazole pharmaceutical wastewater is a big challenge. In this study, a series of anaerobic evaluation tests on pharmaceutical wastewater from different operating units was conducted to evaluate the feasibility of using anaerobic digestion, and the results indicated that the key refractory factor for anaerobic treatment of this wastewater was the high sulfate concentration. A laboratory-scale up-flow anaerobic sludge blanket (UASB) reactor was operated for 195 days to investigate the effects of the influent chemical oxygen demand (COD), organic loading rate (OLR), and COD/SO42? ratio on the biodegradation of sulfamethoxazole in pharmaceutical wastewater and the process performance. The electron flow indicated that methanogenesis was still the dominant reaction although sulfidogenesis was enhanced with a stepwise decrease in the influent COD/SO42? ratio. For the treated sulfamethoxazole pharmaceutical wastewater, a COD of 4983 mg/L (diluted by 50%), OLR of 2.5 kg COD/(m3·d), and COD/SO42? ratio of more than 5 were suitable for practical applications. The recovery performance indicated that the system could resume operation quickly even if production was halted for a few days.  相似文献   
85.
The potential harm of organic pollutants in drinking water to human health is widely focused on in the wodd; more and more pollutants with genotoxic substances are released into the aquatic environment. Water source samples were collected from 7 different localities of Nanjing City. The potential genotoxicity of organic extracts from drinking water sources were investigated by means of the comet assay in human peripheral lymphocytes. The results showed that all the organic extracts from all the water source samples could induce DNA damages of human peripheral blood lymphocytes at different levels. A significant difference (P 〈 0.01) was observed when compared with the solvent control, The DNA damage increased with the increase of the dosage of the original water source. Significant differences of DNA damage were observed in different drinking water sources, as shown by the multiple comparisons analysis at the dosage of 100x; the degree of DNA damage treated by Hushu waterworks (at town level) was the most serious, the arbitrary units (AU) was 141.62±6.96, however, that of Shangyuanmen waterworks (at city level) was only 109.64±2.97. The analysis also revealed that the genotoxicity of town's water sources was higher than that of the city. The results demonstrated that the comet assay can be successfully applied to the genotoxicity monitoring programs of drinking water sources.  相似文献   
86.
非均相Fenton催化剂深度处理维生素C废水的试验   总被引:1,自引:0,他引:1  
为了探究非均相Fenton催化剂对实际废水的处理效果,以维生素C二级生化出水为研究对象,分别考察了针铁矿、磁铁矿和硫铁矿烧渣等含铁矿物质以及部分金属或金属氧化物的吸附性能和非均相Fenton技术的催化氧化性能.选取硫铁矿烧渣作为负载催化剂,融合CuO、Al2O3、TiO2、NiO、Cr2O3、Ag2O,利用高温微孔技术制备非均相Fenton催化剂,当H2O2、FeSO4投加量分别为6.87、4.29 mmol·L-1时,COD去除率能稳定达到70%左右.  相似文献   
87.
Toxic metals accumulated in the human body are predominantly absorbed by the digestive tract in non-occupationally exposed populations. In the current study, we collected plowed soil samples, and investigated the varied food compositions in a mining and smelting area in southwestern China, to measure the concentrations of ten potentially toxic metals—As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sr, and Zn. We collected information on the daily intakes of these metals to assess the health risks associated with their exposure among children and adults. The urine concentrations of the metals were also measured to obtain data on the amounts present in the body. The results showed that the hazard indexes (HIs) of As, Ba, Cd, Cr, Ni, Pb, and Sr were all larger than 1, for both adults and children; the Zn and Cu values were comparatively higher in children. The intake of staple foods of the region posed the greatest health risk, while drinking water only posed risks clearly associated with As exposure. The urine samples of local residents contained larger amounts of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn, confirming the hazards in the health risk assessment. Obvious differences in the urine metal concentrations between men and women were confirmed. In conclusion, higher concentrations of metals in the surface soil and rain water were the predominant cause of elevated exposure through home-grown crops and produce to accumulate in local residents’ bodies.  相似文献   
88.

The release of toxic organic compounds into the environment in an event of oil spillage is a global menace due to the potential impacts on the ecosystem. Several approaches have been employed for oil spills clean-up, with adsorption technique proven to be more promising for the total reclamation of a polluted site. Of the several adsorbents so far reported, adsorbent-based porous materials have gained attention for the reduction/total removal of different compounds in environmental remediation applications. The superior potential of mesoporous materials based on metal–organic frameworks (MOFs) against conventional adsorbents is due to their intriguing and enhanced properties. Therefore, this review presents recent development in MOF composites; methods of preparation; and their practical applications towards remediating oil spill, organic pollutants, and toxic gases in different environmental media, as well as potential materials in the possible deployment in reclaiming the polluted Niger Delta due to unabated oil spillage and gas flaring.

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89.
为合理有效配置公路突发事件下的应急资源,从资源投入与产出角度建立3级评价指标体系,在此基础上将应急资源投入与产出比作为目标函数,引入数据包络分析法构建应急资源配置效率模型,采用TOPSIS法对应急资源配置方案效率进行排序。以新疆10个公路局应急资源配置效率为例,分析其资源投入与产出的冗余度,并对有效决策单元进行排序。结果表明:该模型能获得应急资源配置冗余度,并对其进行资源配置效率分析,从而为公路局进行有效资源配置提供参考。  相似文献   
90.
分析了低DO下,乙酸钠、丙酸钠或葡萄糖作碳源,不同氧化还原电位(ORP)对活性污泥合成聚3-羟基丁酸-co-3-羟基戊酸酯(PHBV)的组分和产量的影响.结果显示,ORP从-30mV(厌氧)增加到 100mV(好氧),PHBV共聚物的产量增加,PHBV共聚物中3-羟基戊酸(HV)单体的摩尔分数降低,细胞生长量和碳源利用量增加;乙酸钠作单一碳源,ORP为-30mV时,PHBV共聚物中HV摩尔分数达到21.0%,ORP为 30mV时,PHBV共聚物在细胞内的质量分数达到35.0%.因此,DO是影响活性污泥合成PHBV共聚物的产量以及PHBV共聚物中HV摩尔分数的重要影响因素.  相似文献   
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