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101.
Feng Y Shi G Wu J Wang Y Zhu T Dai S Pei Y 《Journal of the Air & Waste Management Association (1995)》2007,57(2):164-171
Particle-associated polycyclic aromatic hydrocarbon (PAH) concentrations were investigated at six sampling sites in the heating (February to March 2001) and nonheating (August to September 2001) periods in an industrial city in Northern China. Thirteen PAHs were measured. The total average concentrations (nanograms per meter cubed) of PAHs ranged between 78.93 and 214.63 during the heating period and from 31.48 to 102.26 in the nonheating period. Benzo(a)pyrene occurred at the highest level at a site near an industrial area but occurred at low concentrations far from the city center and industrial areas. In addition, ambient PAH profiles were studied. The five and six-ring species occurred in high fractions at the sampling site. By diagnostic ratio analysis, the major source at each sampling site in the city was coal combustion in the heating period; in the nonheating period, the major sources were relatively complex. Finally, the similarities among the six regions were assessed by principal component analysis, cluster analysis, and coefficient of divergence. These multivariate statistical analyses produced similar results, which agreed with the results from the diagnostic ratio analysis. 相似文献
102.
Eco-environment quality evaluation is an important research theme in environment management. In the present study, Fuzhou
city in China was selected as a study area and a limited number of 222 sampling field sites were first investigated in situ with the help of a GPS device. Every sampling site was assessed by ecological experts and given an Eco-environment Background
Value (EBV) based on a scoring and ranking system. The higher the EBV, the better the ecological environmental quality. Then,
three types of eco-environmental attributes that are physically-based and easily-quantifiable at a grid level were extracted:
(1) remote sensing derived attributes (vegetation index, wetness index, soil brightness index, surface land temperature index),
(2) meteorological attributes (annual temperature and annual precipitation), and (3) terrain attribute (elevation). A Back
Propagation (BP) Artificial Neural Network (ANN) model was proposed for the EBV validation and prediction. A three-layer BP
ANN model was designed to automatically learn the internal relationship using a training set of known EBV and eco-environmental
attributes, followed by the application of the model for predicting EBV values across the whole study area. It was found that
the performance of the BP ANN model was satisfactory and capable of an overall prediction accuracy of 82.4%, with a Kappa
coefficient of 0.801 in the validation. The evaluation results showed that the eco-environmental quality of Fuzhou city is
considered as satisfactory. Through analyzing the spatial correlation between the eco-environmental quality and land uses,
it was found that the best eco-environmental areas were related to forest lands, whereas the urban area had the relatively
worst eco-environmental quality. Human activities are still considered as a major impact on the eco-environmental quality
in this area. 相似文献
103.
Distribution of elements in needles of Pinus massoniana (Lamb.) was uneven and affected by needle age 总被引:1,自引:0,他引:1
Kuang YW Wen da Z Zhou G Liu SZ 《Environmental pollution (Barking, Essex : 1987)》2007,145(3):730-737
Macronutrients (P, S, K, Na, Mg, Ca), heavy metals (Fe, Zn, Mn, Cu, Pb, Cr, Ni, Cd,) and Al concentrations as well as values of Ca/Al in the tip, middle and base sections, and sheaths of current year and previous year needles of Pinus massoniana from Xiqiao Mountain were analyzed and the distribution patterns of those elements were compared. The results indicated that many elements were unevenly distributed among the different components of needles. Possible deficiency of P, K, Ca, Mn and Al toxicity occurred in needles under air pollution. Heavy metals may threaten the health of Masson pine. Needle sheaths were good places to look for particulate pollutants, in this case including Fe, Cu, Zn, Pb, Cr, Cd and Al. 相似文献
104.
Kuang YW Zhou GY Da Wen Z Liu SZ 《Environmental science and pollution research international》2007,14(4):270-275
Goal, Scope and Background Rapid urbanization and the expansion of industrial activities in the past several decades have led to large increases in emissions
of pollutants in the Pearl River Delta of south China. Recent reports have suggested that industrial emission is a major factor
contributing to the damages in current natural ecosystem in the Delta area. Tree barks have been used successfully to monitor
the levels of atmospheric metal deposition in many areas, but rarely in China. This study aimed at determining whether atmospheric
heavy metal deposition from a Pb-Zn smeltery at Qujiang, Guangdong province, could be accurately reflected both in the inner
bark and the outer bark of Masson pine (Pinus massoniana L.). The impact of the emission from smeltery on the soils beneath the trees and the relationships of the concentrations
between the soils and the barks were also analyzed.
Methods Barks around the bole of Pinus massoniana from a pine forest near a Pb-Zn smeltery at Qujiang and a reference forest at Dinghushan natural reserve were sampled with
a stainless knife at an average height of 1.5 m above the ground. Mosses and lichens on the surface barks were cleaned prior
to sampling. The samples were carefully divided into the inner bark (living part) and the outer bark (dead part) in the laboratory,
and dried and ground, respectively. After being dry-ashed, the powder of the barks was dissolved in HNO3. The solutions were analyzed for iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni) and cobalt
(Co) by inductively coupled plasmas emission spectrometry (ICP, PS-1000AT, USA) and Cadmium (Cd) and lead (Pb) by graphite
furnace atomic absorption spectrometry (GFAAS, ZEENIT 60, Germany). Surface soils (0–10 cm) beneath the sample trees were
also collected and analyzed for the selected metals.
Results and Discussion Concentrations of the selected metals in soils at Qujiang were far above their environmental background values in the area,
except for Fe and Mn, whilst at Dinghushan, they were far below their background values, except for Cd and Co. Levels of the
metals, in particular Pb and Zn, in the soils beneath the sample trees at Qujiang were higher than those at Dinghushan with
statistical significance. The result suggested that the pine forest soils at Qujiang had a great input of heavy metals from
wet and dry atmospheric deposition, with the Pb-Zn smeltery most probably being the source.
Levels of Cu, Fe, Mn, Zn, Ni and Pb at Qujiang, both in the inner and the outer bark, were statistically higher than those
at Dinghushan. Higher concentrations of Pb, Fe, Zn and Cu may come from the stem-flow of elements leached from the canopy,
soil splash on the 1.5 m height and sorption of metals in the mosses and lichens growing on the bark, which were direct or
indirect results from the atmospheric deposition. Levels of heavy metals in the outer barks were associated well with the
metal concentrations in the soil, reflecting the close relationships between the metal atmospheric deposition and their accumulation
in the outer bark of Masson pine. The significant (p<0.01) correlations of Fe-Cu, Fe-Cr, Fe-Pb, Fe-Ni, Pb-Ni, and Pb-Zn in
the outer barks at Qujiang again suggested a common source for the metals. The correlation only occurred between Pb and Ni,
Cd and Co in the outer barks at Dinghushan, which suggested that those metals must possibly have other uncommon sources.
Conclusions Atmospheric deposition of the selected metals was great at Qujiang, based on the levels in the bark of Pinus massoniana and on the concentrations in the soils beneath the trees compared with that at Dinghushan. Bark of Pinus massoniana, especially the outer bark, was an indicator of metal loading at least at the time of sampling.
Recommendations and Perspectives The results from this study and the techniques employed constituted a new contribution to the development of biogeochemical
methods for environmental monitoring particularly in areas with high frequency of pollution in China. The method would be
of value for follow up studies aimed at the assessment of industrial pollution in other areas similar with the Pearl River
Delta. 相似文献
105.
高架路桥的震害、震害原因及抗震措施 总被引:2,自引:0,他引:2
对近年来美、日等国的高架道路和高架桥梁所遭受到的地震破坏以及破坏原因进行了概述,对其在高架路桥的规划、设计、施工过程中所要取的抗震措施作了介绍。 相似文献
106.
Zhenshu Wang Yunpeng Shi Xiaodi Wang Qi Zhang Shichao Qu 《International Journal of Green Energy》2016,13(12):1267-1280
The drying up of the fossil energy sources and the damage from unchecked carbon emissions demand the development of low carbon economy, which promotes the development of new energy sources, such as wind power and photovoltaic. However, the direct connections of wind/photovoltaic power into power grid bring great impacts on power systems, thus affecting the security and stability of power system operations, which challenges the power system dispatching. In despite of many methods for power system dispatch, lack of the models, for power system containing wind power and photovoltaic considering carbon trading and spare capacity variation (PSCWPCCTSCV), restricts the further optimal operations of power systems. This paper studies the economic dispatch modeling problem of power system containing wind power and photovoltaic, establishes the model of economic dispatch of PSCWPCCTSCV. On this basis, adaptive immune genetic algorithm is applied to conduct the economic operation optimization, which can provide the optimal carbon trading price and the optimal power distribution coefficient. Finally, simulations based on the newly proposed models are made to illustrate the economic dispatch of PSCWPCCTSCV. The results show that optimization with the proposed model can not only weaken the volatility of the new energy effectively, but also reduce carbon emissions and reduce power generation costs. 相似文献
107.
Robin Warner Mary Kaidonis Olivia Dun Kerrylee Rogers Yubing Shi Thang T. X. Nguyen Colin D. Woodroffe 《Sustainability Science》2016,11(4):661-677
Increasing value is attributed to mangroves due to their considerable capacity to sequester carbon, known as ‘blue carbon’. Assessments of opportunities and challenges associated with estimating the significance of carbon sequestered by mangroves need to consider a range of disciplinary perspectives, including the bio-physical science mangroves, social and economic issues of land use, local and international law, and the role of public and private finance. We undertook an interdisciplinary review based on available literature and fieldwork focused on parts of the Mekong River Delta (MRD). Preliminary estimates indicate mangrove biomass may be 70–150 t ha?1, but considerably larger storage of carbon occurs in sediments beneath mangroves. These natural stores of carbon are compromised when mangroves are removed to accommodate anthropogenic activities. Mangroves are an important resource in the MRD that supplies multiple goods and services, and conservation or re-establishment of mangroves provides many benefits. International law and within-country environmental frameworks offer increasing scope to recognize the role that mangrove forests play through carbon sequestration, in order that these might lead to funding opportunities, both in public and private sectors. Such schemes need to have positive rather than negative impacts on the livelihoods of the many people living within and adjacent to these wetlands. Nevertheless, many challenges remain and it will require further targeted and coordinated scientific research, development of economic and social incentives to protect and restore mangroves, supportive law and policy mechanisms at global and national levels, and establishment of long-term financing for such endeavours. 相似文献
108.
以钛酸丁酯为钛源,掺杂铜(CuCl2)制备交联剂.制得柱状Ti/Cu交联累托石,结合其吸附特性并通过其在光催化氧化条件下处理含硝基苯有机废水.在pH=9,交联累托石用量为30 g/L,一根20 W紫外灯光辐照2 h的处理条件下,硝基苯由73.81 mg/L降至3.17 mg/L,去除率达到95.71%,优于GB-8978-1996三级标准,用其处理含硝基苯工业废水,COD去除率为83.73%,由4800 mg/L降至530.4 mg/L,硝基苯去除率达92.3l%,由10.32 mg/L降至0.79 mg/L,小于GB-8978-1996-级标准. 相似文献
109.
好氧-缺氧一体化高效分离生物流化复合反应器 总被引:1,自引:0,他引:1
鉴于污水处理中对氮、磷去除率的要求和内循环三相生物流化床反应器存在的一些不足,为此,设计开发了一种好氧-缺氧一体化高效分离生物流化复合反应器。该反应器对好氧循环流化区采用了独特的分格结构,当反应器处理规模增大时,在不增加反应器总体高度的基础上,保证了循环流化区的高径比。循环流化反应器与高效气浮分离反应器的耦合,克服了循环流化床以沉淀原理为基础的固液分离效果不佳的状况,既可以保证出水水质,又可以实现反应器的一体化。通过气体提升方式实现了好氧出水回流,使该种反应器能够实现脱氮和部分除磷的目的。该反应器处理生活污水的初步试验结果表明它具有很好的抗冲击负荷和去除有机物的性能。 相似文献
110.
采用溶胶-凝胶法制备锌铝助剂,该助剂于700℃焙烧后与流化催化裂化(FCC)催化剂进行机械混合,制得混合催化剂;在FCC烟气工业模拟装置上考察混合催化剂的脱硫活性,用混合催化剂的脱硫活性来反映锌铝助剂的脱硫性能。实验结果表明,氧化锌质量分数为10%的锌铝助剂的脱硫活性最佳,脱硫率达62.5%。采用红外光谱和X射线衍射(XRD)对锌铝助剂的脱硫机理进行了研究,红外分析结果表明,弱的L酸中心有利于锌铝助剂脱硫,XRD分析结果表明,锌铝助剂在锌铝尖晶石结构尚未完全形成时,存在较多的晶格缺陷,能够有效地吸附烟气中的SOx,将其转化为H2S。 相似文献