Assessing the impact of fungicide enostroburin application on bacterial community in wheat phyllosphere

Fungicides have been used extensively for controlling fungal pathogens of plants. However, little is known regarding the effects that fungicides upon the indigenous bacterial communities within the plant phyllosphere. The aims of this study were to assess the impact of fungicide enostroburin upon bacterial communities in wheat phyllosphere. Culture-independent methodologies of 16S rDNA clone library and 16S rDNA directed polymerase chain reaction with denaturing gradient gel electrophoresis (PCR-DGGE) were used for monitoring the change of bacterial community. The 16S rDNA clone library and PCR-DGGE analysis both confirmed the microbial community of wheat plant phyllosphere were predominantly of the γ-Proteobacteria phyla. Results from PCR-DGGE analysis indicated a significant change in bacterial community structure within the phyllosphere following fungicide enostroburin application. Bands sequenced within control cultures were predominantly of Pseudomonas genus, but those bands sequenced in the treated samples were predominantly strains of Pantoea genus and Pseudomonas genus. Of interest was the appearance of two DGGE bands following fungicide treatment, one of which had sequence similarities (98%) to Pantoea sp. which might be a competitor of plant pathogens. This study revealed the wheat phyllosphere bacterial community composition and a shift in the bacterial community following fungicide enostroburin application.     

基于吸附处理废水中Pb2+的麦糟改性研究

麦糟是啤酒工业的副产物,富含有机物,具有去除废水中重金属离子的能力.为了更有效地去除废水中的Pb2 ,本实验对麦糟进行了改性研究,实验过程中选择HCl、H2SO4、H3PO4、NaCl、NaOH作为改性剂.结果表明,用1mol·L-1NaCl溶液改性13h的麦糟对Pb2 有最好的吸附能力.通过扫描电镜、X射线能谱、红外光谱分析,研究了麦糟改性机理,发现经NaCl溶液改性后的麦糟新增N-Cl基团和C-Cl基团,容易和Pb2 配位结合,从而提高了吸附能力.改性麦糟吸附Pb2 的过程中,N-Cl、C-Cl、C-O(H)以及O-H起了重要作用.     

三苯基锡对紫萍生长及酶活性的毒性作用

以紫萍作为实验生物,通过研究不同浓度的三苯基锡对紫萍（Spirodela polyrrhiza L．）根叶生长、多酚氧化酶（PPO）活性、过氧化氢酶（CAT）活性和过氧化物酶（POD）的影响,为及时发现和排除三苯基锡的污染提供理论和直观依据。结论表明：培养4d后,三苯基锡处理对紫萍叶片生长量的IC50为0．71mg／L。相同培养液条件下,PPO、CAT和POD均随着三苯基锡处理浓度的升高呈现先升高后下降的趋势。从中可以说明三苯基锡对紫萍有明显的毒性作用。     

基于AHP和熵值法的辽宁省城市生态安全评价

随着社会经济的高速发展,生态安全问题越来越重要,它已经成为区域可持续发展的核心问题。以辽宁省的14个城市为研究区域,采用压力-状态-响应模型,选取了26个指标,运用层次分析法（AHP）和熵值法对其生态安全现状进行评价,结果表明：各个城市生态安全值位于0.31~0.8,生态安全水平差异较大。总体来说,沿海地区城市群生态安全较好,中部省会城市群生态安全次之,西部的朝阳、阜新等小城市生态安全较差。最后提出了辽宁省城市生态安全的对策。     

Catalytic oxidation of gas-phase elemental mercury by nano-Fe2O3

Heterogeneous oxidation of gas-phase Hg0 by nano-Fe2O3 was investigated on a fixed bed reactor, and the e ects of oxygen concentration, bed temperature, water vapour concentration and particle size have been discussed. The results showed that Hg0 could be oxidized by active oxygen atom on the surface of nano-Fe2O3 as well as lattice oxygen in nano-Fe2O3. Among the factors that a ect Hg0 oxidation by nano-Fe2O3, bed temperature plays an important role. More than 40% of total mercury was oxidized at 300°C, however, the test temperature at 400°C could cause sintering of nano-catalyst, which led to a lower e ciency of Hg0 oxidation. The increase of oxygen concentration could promote mercury oxidation and led to higher Hg0 oxidation e ciency. No obvious mercury oxidation was detected in the pure N2 atmosphere, which indicates that oxygen is required in the gas stream for mercury oxidation. The presence of water vapour showed di erent e ects on mercury oxidation depending on its concentration. The lower content of water vapour could promote mercury oxidation, while the higher content of water vapour inhibits mercury oxidation.     

宁夏电网新能源发电优先消纳评价机制研究

针对宁夏新能源高速增长,风力发电并网困难的问题,研究了日前评价、日内评价和运行结果评价等多级评价指标体系,建立了宁夏电网新能源发电优先消纳评价机制及新能源发电优先消纳后评价流程。应用结果表明:该评价机制和评价流程有效地提高了宁夏电网对新能源发电的消纳率,实现了新能源发电、送电及消纳的协调统一。     

钻井噪声特性分析与噪声治理

通过对钻井井场噪声源的分布及特性进行现场勘察分析得知:井场区域内各种设备产生的高强度噪声在70～110dB(A)之间,以中低频噪声为主,主要以柴油发电机房为中心,以球面波形式向四周辐射,对井场作业人员及周围250m范围内的居民和环境产生不同程度的噪声危害。为了有效控制噪声对作业人员及井场周围环境的危害,提出了对重点噪声源、噪声传播途径采取隔声、吸声、消声等降噪措施来降低噪声污染。     

SO_3烟气调质对粉尘导电性能的改善机制

以塔山电厂SO3烟气调质运行实测数据为基础条件,通过分析SO3烟气调质后的除尘效率与飞灰比电阻、飞灰粒径、飞灰含湿量等理化性质,揭示SO3烟气调质对燃用高灰分劣质煤电厂除尘性能改善机制。为期一年测试结果表明:调质后比电阻降低3个数量级,2μm以下粒径粉尘比例提高了近6%,含湿量提高14%,从而提高表面导电机制,改善电除尘器电气参数,使电除尘效率由原来98.82%稳定提高至99.91%。     

我国PM_(2.5)污染控制策略及环境影响评价的应对建议

分析了PM2.5对人体健康的危害以及我国PM2.5的污染现状,随后对我国和部分其它国家PM2.5的标准值进行了对比,最后从环境管理的角度出发,提出了PM2.5的控制策略,包括建立灰霾预警机制、强化源头控制、进行区域联防联控等。为了从源头控制PM2.5污染,在环境影响评价工作中,导则体系应增加PM2.5指标,环评中应加强PM2.5现状监测,重视战略环评的区域控制作用,并在项目环评中开展PM2.5影响评价。