乌昌地区资源型产业的集聚特征及其城市化效应研究

以能矿资源为基础原料的资源型产业是工业发展的重要动力,对于资源型产业正处于兴盛期的城市发展更是具有明显的推动作用。论文将资源型产业作为单个影响因素,采用产业结构变动值、产业结构变动系数、产业结构熵数和区位熵等方法,选择典型干旱区城镇发展区域乌昌地区,对该区域资源型产业的时空演化和集聚特征及其对绿洲城镇发展的作用采用定性和定量相结合的方法进行深入分析。结果表明:资源型产业对乌昌地区产业集聚的地域、类型、工业内部结构以及城市的扩展方式和空间结构产生了重要影响;受绿洲城镇分散性的影响,资源型产业对乌昌地区空间结构的影响表现为轴向扩展和圈层扩展并进;资源型产业选择就近城市转移,对于较远的县市集聚大于扩散,中心城镇的辐射带动作用较弱。     

三种氧化铁吸附水环境中砷的试验研究

采用两种人工合成的氧化铁(针铁矿、水铁矿)和赤铁矿作为吸附剂,对含砷(三价砷及三价五价砷混合液)水进行了吸附试验。结果表明,在初始浓度为1200μg/L的As(Ⅲ)溶液中,水铁矿的吸附效果最好,针铁矿和赤铁矿吸附效果较差;在初始pH为7,As(Ⅲ)和As(Ⅴ)摩尔比为1:1的混合液中时,三种铁矿对总砷的吸附效果均随着As/Fe摩尔比的增大而减小;在A(sⅢ)和As(Ⅴ)摩尔比为1:1的混合液中,吸附总砷效果最好的是针铁矿,水铁矿次之,赤铁矿的吸附效果最差;A(sⅤ)的存在对除砷效果有一定的影响,三价砷和五价砷共存时,三种铁矿对其吸附具有一定的选择性。     

不同人工湿地系统处理生活污水的比较研究

以华南1号杂交狼尾草、海芋、春砂仁、文殊兰、美人蕉、沿阶草、鸢尾和红草为湿地植物,以煤渣、麻石、陶粒为填料构成几种人工湿地系统,对生活污水进行处理研究。结果表明:当进水COD浓度小于345mg/L时,各系统出水COD浓度均小于60 mg/L(停留时间为6 h),达到GB 18918-2002的一级B标准;当进水TP浓度在4.44~8.17 mg/L之间,NH4+-N浓度在41.3 mg/L以下,TN浓度在66.1 mg/L以下时,各系统出水TP、氨氮、总氮浓度分别小于1,25,20 mg/L(停留时间为12h),均达到GB18918-2002的二级B标准。     

滇池表层沉积物中氨氮的释放特征

为研究滇池内源污染特征,于2013年在滇池全湖布设36个采样点,采集表层沉积物样品,并对沉积物中w(NH₄+-N)的分布及NH₄+-N释放动力学特征进行研究. 结果显示:滇池表层沉积物中w(NH₄+-N)为155.8～667.8 mg/kg,平均值为333.7 mg/kg,湖心区域最高. 0~5 min内NH₄+-N释放速率最大,可达到3.34～42.31 mg/(kg·min); 5 min后NH₄+-N释放速率逐渐降低,并在120 min左右基本达到释放平衡. 沉积物中NH₄+-N的释放潜能为17 147～34 163 mg/kg,NH₄+-N释放量随着水土质量比的增加而增大;滇池大部分区域NH₄+-N的释放潜能相对较高,特别是在草海北部以及外海盘龙江河口处. 滇池沉积物中NH₄+-N释放速率、释放潜能均高于长江中下游湖泊沉积物;与同为高原湖泊的洱海相比,其沉积物中NH₄+-N释放速率基本相当,但是NH₄+-N释放潜能却远高于洱海,表明滇池表层沉积物中NH₄+-N具有非常高的释放风险.      

Cadmium accumulation and tolerance of two castor cultivars in relation to antioxidant systems

To investigate the effects of Cd on tolerance and antioxidant activities of castor, two different castor（Ricinus communis L.） cultivars（Zibo No. 5 and Zibo No. 8） were used for a hydroponic experiment（0, 1 and 2 mg/L Cd） and a pot experiment using Cd-contaminated soil（34 mg/kg） with the addition of ethylenedinitrilotetraacetic acid（EDTA）. The results indicated that there were significant differences between the two cultivars with respect to Cd uptake in shoots（113–248 mg/kg for Zibo No. 5 and 130–288 mg/kg Zibo No. 8）, biomass tolerance indexes（64.9%–74.6% for Zibo No. 5 and 80.1%–90.9% for Zibo No. 8） in the hydroponic experiment and survival rates（0% for Zibo No. 5 and 100% for Zibo No. 8）determined by the addition of EDTA in the pot experiment, suggesting that Zibo No. 8 has higher tolerance than Zibo No. 5. Moreover, the castor cultivars have low bioconcentration factors（4.80% for Zibo No. 5 and 5.43% for Zibo No. 8） and low translocation factors（〈1%）.Consequently, Zibo No. 8 can participate in Cd phytostabilization in highly Cd-polluted areas. The results indicated that glutathione（GSH） as a non-enzymatic antioxidant, and antioxidant enzymes including superoxide dismutase（SOD）, catalase（CAT） and guaiacol peroxidase（GPX）, were cultivar- and dose-dependent. The higher tolerance of Zibo No. 8compared with Zibo No. 5 can be attributed to the higher GSH levels in the root and higher GPX activity in the leaf.     

沈阳市国三和国四排放标准不同车型柴油车PM2.5和PM10排放因子及碳组分源谱

柴油车是机动车排放的大气颗粒物的主要来源,为研究沈阳市柴油车PM_(2.5)和PM_(10)的排放因子及其碳组分排放特征,采用检车线车载测试方法采集了15辆国三和国四排放标准的小型、中型、大型载客和轻型、中型、重型载货柴油车尾气样品,并对其中的碳组分进行化学分析.结果表明,国三柴油车PM_(2.5)和PM_(10)的排放因子分别为(0. 193±0. 092) g·km-1和(0. 338±0. 305) g·km-1,国四柴油车PM_(2.5)和PM_(10)的排放因子分别为(0. 085±0. 038) g·km-1和(0. 100±0. 042) g·km-1,随排放标准的提升PM_(2.5)和PM_(10)排放因子显著下降.同一排放标准下,排放因子随车型的增大而增大. TC为柴油车的主要组分,国四柴油车中TC的质量分数(23%～48%)明显低于国三柴油车(29%～70%).各车型柴油车元素碳(EC)的质量分数均大于有机碳(OC),OC/EC为0. 70±0. 29,且国四柴油车OC/EC值低于国三柴油车.因载客汽车总行驶里程明显高于载货汽车导致油耗较高,相同排放标准载客汽车OC和EC的质量分数高于载货汽车.国三、国四柴油车质量分数最高的碳组分均为EC2,可将EC2作为柴油车的标识组分.     

Strong ozone production at a rural site in theNorth China Plain: Mixed effects of urban plumesand biogenic emissions

Regional ozone (O₃) pollution has drawn increasing attention in China over the recent decade, but the contributions from urban pollution and biogenic emissions have not been clearly elucidated. To better understand the formation of the regional O₃ problem in the North China Plain (NCP), intensive field measurements of O₃ and related parameters were conducted at a rural site downwind of Ji'nan, the capital city of Shandong province, in the summer of 2013. Markedly severe O₃ pollution was recorded, with the O₃ mixing ratios exceeding the Chinese national ambient air quality standard on 28?days (a frequency of 78%) and with a maximum hourly value of 198 ppbv. Extensive regional transport of well-processed urban plumes to the site was identified. An observation-constrained chemical box model was deployed to evaluate in situ photochemical O₃ production on two episodes. The results show that the in situ formation accounted for approximately 46% of the observed O₃ accumulation, while the remainder (~ 54%) was contributed by regional transport of the O₃-laden urban plumes. The in situ ozone production was in a mixed controlled regime that reducing either NOx or VOCs would lead to a reduction of ozone formation. Biogenic VOCs played an important role in the local ozone formation. This study demonstrates the significant mixed effects of both anthropogenic pollution from urban zones and biogenic emission in rural areas on the regional O₃ pollution in the NCP region, and may have general applicability in facilitating the understanding of the formation of secondary pollution over China.     

汾河水质状况研究

通过对十年来汾河沿程21个断面的常规水质监测数据进行整理分析,筛选出5项主要污染指标,采用综合水质指数法分析汾河及上、中、下游各河段水质变化趋势,运用沿程水质变化和几个重要水质指标的比值变化分析汾河水质状况和污染特征,总结主要污染指标的变化趋势,结合汾河流域实际排污情况探讨水质污染和改善原因,并对进一步改善汾河水环境质量提出建议。     

非平衡等离子体降解两种不同VOCs的研究

实验以甲醛和苯乙烯为研究对象,采用介质阻挡放电,考察了放电电压、初始浓度和停留时间对他们降解率的影响,并对两者的能耗进行了分析。研究发现甲醛和苯乙烯的降解率随放电电压、初始浓度和停留时间的增大均呈现不同的变化趋势:随着放电电压和停留时间的增大,甲醛的降解率较苯乙烯增加得慢,且达到一定值后有趋于平缓的趋势;而当初始浓度增大时,甲醛的降解率先增大后减小,出现一个最佳降解浓度区域,苯乙烯的降解率则直接快速减小;在输入的能量较高时,苯乙烯的能量利用率更高。     

淄博市重点工业行业VOCs排放特征

为研究淄博市重点工业行业的VOCs排放特征,筛选出9个重点行业,选择各行业代表性企业进行实地调研和采样,分析了不同行业的VOCs排放特征,通过实测法计算了各企业的VOCs排放量,并在此基础上得到本地化排放因子.结果表明,不同行业的VOCs排放特征存在一定差异,多数行业以烷烃、卤代烃为主;乙烷、乙炔、氯乙烷类(包括1,1-二氯乙烷、 1,1,1-三氯乙烷)以及氟利昂类(氟利昂12或氟利昂114)为大多数行业均含有的主要特征物种;分环节排放量计算结果显示,设备动静密封点泄漏、有机液体装卸挥发损失、有机液体储存与调和挥发损失以及工艺有组织排放为不同类型石化行业的VOCs主要排放环节,排放量占比均达到40%以上;合成橡胶与炼钢行业的VOCs本地化排放因子与已有规范中的推荐值相近,其余行业则存在较大差距.