Marine Radar Oil-Spill Monitoring through Local Adaptive Thresholding

Marine oil spills affect the environment, economy, and quality of life for coastal inhabitants. This article presents a method of X-band marine radar oil-spill identification by considering the marine radar images of the 2010 Dalian 7-16 accident. The Prewitt operator was improved and a linear interpolation was proposed to suppress co-channel interferences. In addition, a model of a gray-intensity-correcting matrix is proposed to smooth a whole image, thus displaying the oil film more intuitively. Furthermore, a contrast-limited adaptive histogram equalization method was used to increase the contrast inside and outside the oil film. Moreover, the local adaptive thresholding method was improved to segment the oil spills. The results show that the proposed method is an improvement on similar previous approaches for this task when employing X-band marine radar images. The proposed method can provide technical and theoretical bases for emergency response, damage assessment, and liability identification of oil spills.     

壳聚糖改性高炉渣对水溶性染料的吸附

采用壳聚糖改性高炉渣制备复合吸附剂(C-BFS)。在吸附温度为30℃、溶液pH为3、初始染料质量浓度为60 mg/L、C-BFS加入量为6 g/L的最佳条件下,C-BFS对活性艳红K-2BP、活性红195、酸性蒽醌蓝、酸性红B 4种染料溶液的脱色率均可达95%以上。4种染料在C-BFS上的吸附很好地符合Langmuir等温方程,吸附动力学均可用表观二级动力学模型描述。热力学参数表明C-BFS对4种染料的吸附都是自发进行的,主要为物理吸附,吸附过程无配位基交换、化学键等强的作用力。     

Resource and Environmental Issues in Transitional China： A Perspective from the Interaction Among Market, Government and Society

Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society.This article explores an effective mechanism of managing resource and environment in China.It examines some major resource and environmental issues,and constructs a framework of institution innovation to cover three sectors(government,market and society).In addition,the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period.We argue that the combination of market regulation,government intervention and public participation is an effective way of allocating resource and protecting environment.Some suggestions are put forward to balance the relationship between them,including coordinating role of government and market,building platform for market operation and creating an atmosphere of public participation.     

甲醛清除剂净化效果的实验舱测试和分析

为了对市售被动式室内空气净化产品的净化效果有深刻具体的认识,选择销售份额较大的4种甲醛清除剂进行实验舱测试。结果表明:(1)甲醛清除剂对甲醛的净化过程均随时间呈对数衰减,可见甲醛浓度越高,甲醛清除剂对甲醛的净化速率越快。(2)不同的甲醛清除剂的净化速率都有一定差异,即使24h净化率均在90%以上的甲醛清除剂,净化速率也不同,净化率达到90%以上所需要的实际时间可相差数倍。(3)《室内空气净化功能涂覆材料净化性能》(JCT 1074—2008)中对甲醛清除剂根据其对污染物24h的净化率进行了分级,消费者可据此对净化产品的优劣有初步判断。而净化速率和饱和净化量则可在消费者购买甲醛清除剂时起到更具体和明确的指导作用,并可在消费者具体使用时,根据饱和净化量,对甲醛清除剂用量和甲醛清除剂持续作用时间有初步的判断。     

基于综合气象干旱指数（CI）的干旱时空动态格局分析——以甘肃省黄土高原区为例

借助ArcGIS9．3和SPSS数据软件平台,根据甘肃省黄土高原区33个气象站1962-2010实测气象资料,利用综合气象干旱指数（CI）对甘肃省黄土高原区近50年的干旱特征进行了时空分析。首先计算了各站历年逐日的CI指数,统计近50年各站点出现的干旱过程、各时段的干旱事件,在此基础上分析了甘肃省黄土高原区历年各地区干旱发生的覆盖范围、频率和不同等级干旱发生的多年平均天数,揭示了甘肃省黄土高原区干旱发生的时空差异和动态格局。分析结果表明,（1）甘肃省黄土高原区有大范围干旱发生的年份,夏季和秋季较多分别有13、8a,冬季最少,只有3a。（2）从空间尺度来看,甘肃省黄土高原区中兰州一榆中一靖远一带和庆阳北部属于高值区,而岷县、渭源一带属于低值区;106°E以西“临洮．通渭．天水”一带和庆阳东南部是干旱变幅最大的地方。（3）从季节尺度来看,夏季干旱频率和持续日数最多,春季、秋季次之,冬季最少。     

Pollution characteristics of lead,zinc, arsenic,and cadmium in short-term storm water roof runoff in a suburban area

Pollution of hazardous elements in roof runoff has been a potential danger to aquatic ecosystem as documented in previous studies. In this study, concentrations of lead (Pb), zinc (Zn), arsenic (As), and cadmium (Cd) in roof runoff were measured for short-term rainfall events. The concentrations of the selected elements varied to a high degree during the rainfall period, and the well-known first-flush phenomenon was not observed due to the short-term rainfall patterns. Based on event mean concentrations (EMCs) and fluxes, the elemental pollution may be ranked as Zn >> Pb > As > Cd. The average levels of Pb and Zn exceeded the fourth class value and fifth class value of the environmental quality standards for surface water in China. The relative high pollution could be caused by atmospheric deposition and the erosion of crust steel appurtenance installed above the rooftop. Furthermore, elements in particulate form dominated the roof runoff pollution, and the ratios of elements in particulate form to total amounts were 0.6 (As), 0.9 (Pb), 0.7 (Cd), and 0.5 (Zn). This study cleared the pollution characteristics of hazardous elements in short-term storm water roof runoff; it was useful for the selection of best management practices.     

Analysis of a high PM10 episode observed at a coastal site nearby Shanghai, China

A high PM₁₀ episode observed at a coastal site nearby Shanghai during 18–19 January 2007 was analyzed in this study. The maximum hourly averaged PM₁₀ concentrations for the 2 days were 0.58 and 0.62 mg/m³, respectively. The meteorological condition during the episode was favorable for air pollution with large-scale stagnation. There was no dispersing effect by high wind, no scavenging function by precipitation, and no diluting process by clean marine air during the episode. The trajectories for 16–19 January all came from the northern region and kept in low levels, and during the episode peak time, from the morning of 18 to the morning of 19 January, trajectories all came from the northern inland areas and had passed over the coastal region of Jiangsu province before arriving at the site. The variation of the air pollution indexes (APIs) in the cities located in the upwind direction of the site during the episode days clearly shows a process of large-scale air pollution from north to south. The liner correlation coefficient for PM₁₀ and SO₂ concentrations is 0.774 during the episode, while for PM₁₀ and CO, it even reaches 0.995, which indicated that the high PM₁₀ was mainly emitted from the coal burning for domestic heating in winter. Therefore, the observed episode was caused by the transport of domestic heating pollutants accumulated in the boundary layer from northern continental areas.     

Photocatalytic degradation of 4-tert-octylphenol in a spiral photoreactor system

A spiral photoreactor system (SPS) was developed for the degradation of 4-tert-octylphenol (4-t-OP) in aqueous phase. 4-t-OP was previously considered as a endocrine disrupting compound frequently present in water. The direct photodegradation reaction caused by the SPS was found to accord with the characteristic of apparent first-order reaction with reaction rate constantk= 4.8 × 10^-2 min^-1. However, the direct photodegradation reaction could not make the 4-t-OP mineralized. The photodegradation efficiency increased from 88% to 91.2% in 45 min irradiation period after the internal surface of SPS was sintered with TiO₂ thin film as catalyst. Catalyst concentration, number of catalyst coating layers and initial concentration of 4-t-OP were proven to be the factors affecting the photocatalytic degradation performance of the SPS on aqueous 4-t-OP. The degradation mechanism was investigated and the byproducts were analyzed using total organic carbon analyzer (TOC) and LC-MS. The possible chemical structures of the products were suggested. SPS with single layer of TiO₂ prepared by sintering 13.6% of TiO₂ precursor was proven to be more efficient than most of previous systems for removal of 4-t-OP from aqueous phase. 28.3% of the 4-t-OP was mineralized in 45 min according to the decreased amount of TOC value.     

中国生活垃圾处理处置公众参与和社会监督法规现状研究

随着中国城市化进程的加快,城市生活垃圾产生量逐年增加,生活垃圾处理处置压力也与日俱增,迫切需要建立针对处理处置的公众参与机制。本文分析了国内外环境保护公众参与相关法律制度现状以及中国生活垃圾公众参与的情况,参与积极性不强,参与渠道和方式有限,相关法律法规不健全,环境立法忽视公民的环境权和参与决策权。指出要在中国生活垃圾处理处置全过程中引入公众参与,并全面建立废弃物处理处置信息公开制度,并贯彻实施,必须明确环境权和采取信息公开的制度。     

上海市2006～2008年实施燃煤电厂烟气脱硫的综合经济分析

根据上海市新一轮“环境保护和建设三年行动计划”（2006-2008年）提出的未来3年全市将有11家电厂的35台共约650.8万kW燃煤发电机组实施烟气脱硫的目标，结合上海市实际，建立相关假定条件，并考虑SO2减排的作用及脱硫产物的利用等方面因素，从经济、环境等角度对上海市650.8万kw燃煤发电机组实施湿法烟气脱硫的成本、效益进行了综合分析。结果显示，燃煤电厂烟气脱硫的固定资产投资和运行费用均较大，而脱硫产生的直接经济效益相对较小，其效益更多地体现在无法直接以货币形式衡量的环境效益、社会效益上。