秦皇岛市海港区城市游憩绿地发展对策研究

从秦皇岛市海港区城市游憩绿地存在的空间分布不均匀、设计不完善、疏于管理、服务设施不足等问题出发,提出了从宏观调控、游憩绿地设计、管理、法制、可持续发展和建设投入角度发展海港区城市游憩绿地的对策,从而提高城市人居环境质量,充分发挥城市游憩绿地系统在整个城市绿地系统中的重要地位。     

钢铁企业无组织排放特征污染物的监测分析

东部老工业区是济南市大气污染重点防控区域。工业区大型企业的无组织排放废气对区域及周边大气环境质量产生的影响,一直没有引起人们的足够重视,因对其排放量大小和污染物种类不清楚,难以进行监管。本文以济南东部老工业区一家大型钢铁企业为例,选取五项有代表性的特征污染物(苯、甲苯、二甲苯、非甲烷总烃和氨)进行布点监测,在不同气象条件下,分析特征污染物的浓度变化,了解钢铁企业无组织排放特征。经对监测数据的分析得出:与上风向相比,下风向各污染物监测的小时浓度和日均浓度均有不同程度的增加,表明该厂区污染源对周边环境空气质量有一定影响。最后,提出防范或改进措施,如应加严相应的无组织排放标准,增加大气在线监测点位及监测项目,建议企业加强对生产工艺环节无组织排放废气的收集和处理。     

柳州市2009-2014年空气污染变化

近年来,城市空气污染日益严重,已成为公众广泛关注的环境问题之一。柳州是中国西部的工业重镇、广西有名的工业城市,位列国家划定的113个大气污染防治重点城市之中,是广西第一个开展PM2.5监测的城市。本研究于2009—2014年连续6年对柳州市大气主要污染物SO2、NO2、PM10和PM2.5的浓度进行在线观测,获得了污染物的长期时间和空间分布特征。结果显示,SO2浓度呈逐年下降趋势,并于2011年达标之后显著下降,2014年相比2009年下降了50.0%;NO2浓度一直在低于标准以下波动(24.6~35.1μg/m3);PM10浓度呈逐年增长趋势,并从2011年开始超标,2014年相对于2009年增长了69.3%。各污染物浓度都具有显著的季节变化:冬季秋季春季夏季。SO2、NO2、PM10和PM2.5的浓度冬季相比夏季分别提高82.9%、56.3%、66.9%和133.6%。冬季SO2和秋冬季PM10超标,PM2.5除7月外全线超标。PM2.5/PM10的比值冬季也高于夏季,表明冬季更易富集细颗粒。各污染物浓度也表现出不同的空间分布。九中各污染物的浓度都最高,可能与其离柳州钢铁公司距离较近有关。SO2除九中外,其他站点均达标。NO2全部达标。PM10市监测站和九中超标。PM2.5所有站点超标严重。本研究结果表明,柳州市煤烟型污染得到有效控制,但颗粒物污染,尤其是细颗粒物污染日益严重。     

One way to reduce the NOX Emission of biodiesels: The increase of cetane number

Compared to conventional diesel fuels, biodiesels normally have lower smoke and particulate matter, while higher nitrogen oxides (NO_X) emissions. In our study, an attempt was made to reduce the NO_X emissions of biodiesels by increasing the cetane numbers (CNs). Three kinds of biodiesels with extremely high CNs (70.1, 76.9, 80.9, respectively) were developed. Their main physical and chemical properties were tested. With a two-cylinder direct injection diesel engine, their emission performances were experimentally investigated. The results indicate that, CN, freezing point, as well as viscosity of biodiesels are linearly increased with the increase of carbon number. The NO_X emission for biodiesels with high CNs is lower than that of conventional diesel fuels. High CN promotes smoke formation as well while lower smoke emissions are still obtained for biodiesels when certain oxygen contents are present. That is, the smoke/NO_X tradeoff is broken. Besides, as fuel CN is elevated, NO_X for biodiesels decreases but smoke and carbon monoxide emissions are increased.     

生态混凝土应用现状

生态混凝土是近年来日益受到关注的新型混凝土材料.它是一种既不破坏环境,又能保护环境,对实现人类与自然环境的协调具有积极作用的特种混凝土.本文介绍了生态混凝土的概念及分类,阐述了生态混凝土的应用现状,指出生态混凝土是一种新型的生态建筑材料,具有广阔的应用前景.     

Adsorption of Pb and Cd on the natural surface coatings (NSCs) in the presence of organochlorine pesticides: a preliminary investigation

Adsorption of Pb and Cd in the presence and absence of organochlorine pesticides (OCPs) on natural surface coatings (NSCs), which were collected in the Nanhu Lake in Changchun, China, was measured in order to investigate the effect of the OCPs on the adsorption of heavy metals on the NSCs. Adsorption of Pb/Cd was carried out under controlled laboratory conditions (mineral salt solution with defined species, ionic strength 0.05 mol/l, 25 degrees C and pH 6.0) with initial Pb and Cd concentrations ranging from 0.2 to 2.5 mol/l. The classical Langmuir adsorption isotherm was applied to estimate the equilibrium coefficients of the adsorption of Pb and Cd on the NSCs. Adsorption interference between Pb/Cd and the OCPs on the NSCs indicated that the adsorption of Pb/Cd on the NSCs was influenced by the OCPs, and competitive adsorption between Pb and the OCPs was observed while adsorption of Cd was enhanced by addition of the OCPs. Adsorption data fit the Langmuir isotherm well for the NSCs treated with the OCPs at different equilibrium concentrations. The results showed that the amount of adsorbed Pb decreased by more than 40% while the amount of adsorbed Cd increased by over 60% with an increase in the initial concentrations of the OCPs ranging from 0 to 5.0 microg/l and that adsorption of Pb/Cd on the NSCs was strongly affected by the OCPs. This preliminary study highlights the importance of the OCPs on the NSCs in controlling the transport, fate, biogeochemistry, bioavailability and toxicity of trace metals in aquatic environments.     

城市污水处理厂剩余污泥热值测定方法优化研究

目前的城市污水处理厂剩余污泥热值的测定主要参考煤热值的测定方法。根据污泥的特性,对热值测定过程中污泥的干燥方式、助燃剂的影响和热值校正计算3个方面进行了优化研究。结果表明,冷冻干燥(-50℃)能够避免污泥有机物的挥发,从而精确地测定剩余污泥的热值;对于有机物含量较高的污泥(VS/TS>0.57),不添加助燃剂也能准确测定污泥的热值;通过测定氧弹洗液中硫酸和硝酸的含量来计算热值校正,从而准确得到污泥的热值。     

Black Disease (Terpios hoshinota): A Probable Cause for the Rapid Coral Mortality at the Northern Reef of Yongxing Island in the South China Sea

The northern reef of Yongxing Island, the largest reef island of the Xisha Islands in the South China Sea, was in good condition with significant cover of scleractinian corals until 2002. Surveys in 2008 and 2010, however, found that coral coverage had declined rapidly and severely, implying that catastrophic coral mortality occurred during the past 8 years. A blackish mat was observed covering live and dead corals in both 2008 and 2010 that was identified as an encrusting sponge, Terpios hoshinota, by special surface morphology and spicule structure. In addition, spicule residues were found on the surface of long-dead corals, indicating a previous invasion of T. hosinota. T. hoshinota is referred to as the "black disease" because it rapidly overgrows and kills corals. Our evidence indicates that outbreaks of black disease are at least partially responsible for the massive coral mortality at the northern reef of Yongxing Island over the past 8 years, although human activities and heat-related coral bleaching cannot be discounted as minor causes for this coral decline.     

Algae community and trophic state of subtropical reservoirs in southeast Fujian, China

Background,

aim, and scope Fujian reservoirs in southeast China are important water resources for economic and social sustainable development, although few have been studied previously. In recent years, growing population and increasing demands for water shifted the focus of many reservoirs from flood control and irrigation water to drinking water. However, most of them showed a rapid increase in the level of eutrophication, which is one of the most serious and challenging environmental problems. In this study, we investigated the algae community characteristics, trophic state, and eutrophication control strategies for typical subtropical reservoirs in southeast Fujian.

Materials and methods

Surface water samples were collected using polyvinyl chloride (PVC) plastic bottles from 11 Fujian reservoirs in summer 2010. Planktonic algae were investigated by optical microscopy. Water properties were determined according to the national standard methods.

Results and discussion

Shallow reservoirs generally have higher values of trophic state index (TSI) and appear to be more susceptible to anthropogenic disturbance than deeper reservoirs. A total of 129 taxa belonging to eight phyla (i.e., Bacillariophyta, Chlorophyta, Chrysophyta, Cryptophyta, Cyanophyta, Euglenophyta, Pyrrophyta, Xanthophyta) were observed and the most diverse groups were Chlorophyta (52 taxa), Cyanophyta (20 taxa), Euglenophyta (17 taxa), Chrysophyta (14 taxa). The dominant groups were Chlorophyta (40.58%), Cyanophyta (22.91%), Bacillariophyta (21.61%), Chrysophyta (6.91%). The species richness, abundance, diversity, and evenness of algae varied significantly between reservoirs. TSI results indicated that all 11 reservoirs were eutrophic, three of them were hypereutrophic, six were middle eutrophic, and two were light eutrophic. There was a strong positive correlation between algal diversity and TSI at P?4-N, NO _x -N, TP, and chlorophyll a were significant environmental variables affecting the distribution of algae communities. The transparency and chlorophyll a were the strongest environmental factors in explaining the community data. Furthermore, the degradation of water quality associated with excess levels of nitrogen and phosphorus in Fujian reservoirs may be impacted by interactions among agriculture and urban factors. A watershed-based management strategy, especially phosphorus control, should be developed for drinking water source protection and sustainable reservoirs in the future.

Conclusion and recommendations

All investigated reservoirs were eutrophicated based on the comprehensive TSI values; thus, our results provided an early warning of water degradation in Fujian reservoirs. Furthermore, the trophic state plays an important role in shaping community structure and in determining species diversity of algae. Therefore, long-term and regular monitoring of Euglenophyta, Cyanophyta, TN, TP and chlorophyll a in reservoirs is urgently needed to further understand the future trend of eutrophication and to develop a watershed-based strategy to manage the Cyanophyta bloom hazards.     

Fenton氧化/高浓度泥浆法处理矿山废水

为了解决某大型铜矿废水COD不达标问题,采用Fenton氧化对原有高浓度泥浆（HDS）工艺进行改进。探讨了Fenton氧化矿山废水各指标的去除效果以及H₂O₂浓度对出水COD去除效果的影响,结果表明,Fenton氧化-电石乳中和絮凝沉淀工艺处理矿山废水是可行的,最优实验条件为：pH稳定在3.0～4.5,H₂O₂投加量0.5 mL/L,电石乳投加量8.5 g/L,PAM投加量1.5 mg/L;系统对废水COD的去除机理是加入的H₂O₂和矿山酸性废水中的Fe²⁺离子在低pH下形成Fenton试剂;系统对TFe、Zn²⁺、Cu2+ 的去除效果比Mn²⁺的去除效果更稳定。