"十二五"期间辽河流域的典型流域土地利用组成和变化分析研究

在遥感影像数据基础上,采用ERDAS和ArcGIS分析得出"十二五"期间清河、凡河和蒲河3个流域的土地利用组成及变化.结果表明:清河流域和凡河流域土地利用以林地为主,自然类型面积之和占流域总面积比例超过50%,蒲河流域则以耕地和建设用地等人工类型为主,面积之和占比超过80%;"十二五"期间各流域的土地利用类型均存在不同程度自然类型向人工类型转化的现象,清河流域变化最大,蒲河最小.     

水专项"十三五"时期辽河流域水环境管理研究思路初探

以水专项在辽河流域实施的阶段性成果及辽河流域水环境管理现状为基础,分析"十三五"时期辽河流域水环境管理的需求,提出构建成套流域水环境管理技术体系和管理大平台、全面建设并优化水生态环境监测网络、实行水环境管理的动态调节机制和建立健全流域水环境管理长效机制的水环境管理研究思路,并指出研究应密切结合地方管理,充分发挥地方环境管理的责任主体地位,为水专项第三阶段"综合调控"战略目标的实现提供有力支撑.     

江西西华山钨矿床流体包裹体特征及成矿流体来源

本文对江西西华山钨矿床的石英流体包裹体进行了岩相学和显微测温分析,研究了石英流体包裹体的气、液相组分及碳、氢、氧同位素特征。结果表明,石英中流体包裹体十分发育,包裹体类型有NaCl-H2O(盐水)包裹体(Ⅰ)和CO2-H2O包裹体(Ⅱ),且以前者为主。包裹体均一温度在200℃～280℃,平均249.5℃;盐度为7.89%～13.95%,平均10.73%;成矿流体密度为0.628g/cm3～0.895g/cm3,平均0.795g/cm3,属低盐度低密度范畴;压力平均值为64.01MPa,对应的成矿深度平均值为6.45km。成矿热液气相成分以H2O为主,CO2含量低;液相成分阴阳离子浓度都很低,相对富钠和氯,流体离子类型大致呈Na+-K+-Cl--SO42-型。成矿流体基本来自岩浆水,部分可能有变质水的加入;流体中碳主要由岩浆水提供,少数由地幔源提供。     

黄河入河沙漠颗粒物对磷酸盐的吸附特征

研究了黄河入河沙漠颗粒物在天然水(河水和海水)中对磷酸盐的吸附行为,用改进的Langmuir和Freundlich等温吸附模型对实验数据进行了拟合.结果表明,①改进的Langmuir等温吸附模型更适用于描述黄河入河沙漠颗粒物对磷酸盐的吸附特征,其物理意义更明确,得到的拟合参数更合理;②颗粒物对磷的最大吸附容量Qmax变化范围为41.322～357.143mg.kg-1,其中居延海颗粒物Y2的Qmax最大.Qmax与颗粒物(Y1～Y5)的有机质有着极显著的正相关关系;③除巴丹吉林沙漠颗粒物Y1外,颗粒物的临界磷平衡浓度EPC0值均大于其相应水体的磷浓度.Y1在黄河水中吸附磷的EPC0小于相应水体的磷浓度0.0100.053 mg.L-1,而在渤海海水中却大于相应水体的磷浓度0.1090.074 mg.L-1,表明Y1吸附了黄河水中的磷,进入渤海后Y1原有吸附可交换态磷NAP转移到海水中.其它颗粒物与相应水体进行磷交换的过程中存在着解吸磷的现象,具有向相应水体释放磷的能力;④黄河入河沙漠颗粒物对磷酸盐的吸附等温线是过溶液浓度轴0.00的交叉型等温线,这种新型交叉型吸附-解吸模型较好地解释了其吸附特征和天然粒子的双重性作用.     

内循环三相生物流化床处理生活污水的试验研究

对内循环三相生物流化床处理生活污水进行了试验研究,探讨了生物膜的形成和水力停留时间及曝气量对处理效果的影响。结果表明：在HRT为6h,曝气量为0.6m3/h,进水COD和NH4＋-N分别为240.2~298.7mg/L和29.1~68.9mg/L条件下,平均COD去除率为83%,NH4＋-N去除率为95.1%。     

Diversity of crude oil-degrading bacteria and alkane hydroxylase (<Emphasis Type="Italic">alkB</Emphasis>) genes from the Qinghai-Tibet Plateau

The aim of this study was to survey the response of the microbial community to crude oil and the diversity of alkane hydroxylase (alkB) genes in soil samples from the Qinghai-Tibet Plateau (QTP). The enrichment cultures and clone libraries were used. Finally, 53 isolates and 94 alkB sequences were obtained from 10 pristine soil samples after enrichment at 10 °C with crude oil as sole carbon source. The isolates fell into the phyla Proteobacteria, Actinobacteria, and Bacteroidetes, with the dominance of Pseudomonas and Acinetobacter. The composition of degraders was different from polar habitats where Acinetobacter sp. is not a predominant responder of alkane degradative microbial communities. Phylogenetic analysis showed that the alkB genes from isolates and enrichment communities formed eight clusters and mainly related with alkB genes of Pseudomonas, Rhodococcus, and Acinetobacter. The alkB gene diversity in the QTP was lower than marine environments and polar soil samples. In particular, a total of 10 isolates exhibiting vigorous growth with crude oil could detect no crude oil degradation-related gene sequences, such as alkB, P450, almA, ndoB, and xylE genes. The Shannon-Wiener index of the alkB clone libraries from the QTP ranged from 1.00 to 2.24 which is similar with polar pristine soil samples but lower than that of contaminated soils. These results indicated that the Pseudomonas, Acinetobacter, and Rhodococcus genera are the candidate for in situ bioremediation, and the environment of QTP may be still relatively uncontaminated by crude oil.     

水质凯氏氮标准样品的研究

提出了水质凯氏氮标准样品的研究方法。在研究过程中，完成了样品的配制、均匀性、稳定性等工作。经过多家实验室协作定值，确定了样品的标准值及不确定度，并提供使用。     

巯基化合物在万寿菊镉解毒中的作用

采用水培实验方法研究了万寿菊体内镉积累和解毒与巯基化合物含量的关系。万寿菊植株分别在镉浓度为0、0.1、0.5、2和8 mg/L的营养液中暴露7 d,测定了根、茎、叶中镉、非蛋白巯基(NPT)、半胱氨酸(Cys)、γ-谷氨酰半胱氨酸(γ-EC)、谷胱甘肽(GSH)和植物络合素(PCs)的含量。植物根、茎、叶中镉含量都随着镉暴露浓度的增加而增加。当溶液中镉浓度较低(0.1～2 mg/L)时,茎叶中NPT、PCs、Cys和γ-EC含量随着镉浓度增加而增大;当镉浓度较高(8 mg/L)时,茎叶中PCs含量迅速降低,GSH含量大幅度增高。在根部,这些巯基化合物的含量几乎不受镉处理影响,且含量较低。以上研究结果表明:PCs在万寿菊镉的解毒机制中发挥一定的作用,暴露于高浓度的镉,GSH比PCs起着更为重要的解毒作用。     

Trends and Relationships of O3, NOx and HC in the South Coast Air Basin of California

A basin-wide air quality trend analysis for the South Coast Air Basin of California is conducted for hydrocarbons (HC), NO_x, O₃ and CO using multi-station composite daily maximum-hour average ambient concentrations for the third quarter (July, August and September) from 1968 to 1985. Emissions and air quality trends are compared for the period 1968-1984. Ambient HC and NOX trends are somewhat different from estimated emission trends of HC and NO_x, while a definite, downward trend of ambient CO is consistent with vehicular emission control measures. Basin-wide ambient HC, NO_x and O₃ appear to show downward trends for the period 1970-1985, but because of high fluctuations it is difficult to delineate trends for shorter periods. The meteorology (850 mb temperature)-adjusted O₃ shows a more consistent downward trend than does unadjusted O₃. Polynomial and multiplicative regression models for basin-wide empirical O₃-HC-NO_x relationships Indicate that the O₃ variation is explained largely by the meteorological variable (850 mb temperature) although model estimations are improved by adding HC and NO_x concentration terms.     

Stabilization and solidification of elemental mercury for safe disposal and/or long-term storage

A simple and highly effective stabilization/solidification (S/S) technology of elemental mercury using only sulfur with paraffin is introduced. First, elemental mercury is mixed with an excess of sulfur powder and heated to 60 degrees C for 30 min until elemental mercury is converted into mercuric sulfide (HgS black, metacinnabar) (Step 1). Then, metacinnabar with additional sulfur is poured into liquid paraffin (Step 2). Finally, the mixture is melted at 140 degrees C and settles to the bottom of the vessel where it cools and solidifies under the layer of liquid paraffin (Step 3). The proposed S/S method with sodium sulfide nonahydrate (Na2S x 9H2O) as an additive is also tested for comparison. The average toxicity characteristic leaching procedure test values are 6.72 microg/L (no additive) and 3.18 microg/L (with additive). Theses concentrations are well below the Universal Treatment Standard (25 microg/L). Effective diffusion coefficient evaluated from accelerated leach test and average headspace concentration of Hg vapor after 18 hr are 3.62 x 10(-15) cm2/sec, 0.55 mg/m3 (no additive) and 5.86 x 10(-13) cm2/sec, 0.25 mg/m3 (with additive).