藻类有机质的组成结构对菲和壬基酚生物吸附的影响

对不同来源藻及其有机级分进行元素分析,利用高级核磁共振技术(multi/CP13C NMR)来准确地定量其有机官能团,并研究它们对菲和壬基酚的生物吸附行为和机理。结果表明游离脂和非水解有机碳级分对菲和壬基酚有最高的吸附能力,其吸附容量与脂肪结构呈极显著的正相关,而与极性官能团呈极显著的负相关;而且对壬基酚的吸附容量都大于对菲的吸附容量,可以用专性作用(如π-π键作用和氢键作用)来解释。     

Purification of contaminated paddy fields by clean water irrigation over two decades

Paddy fields near a mining site in north part of Guangdong Province, PR China, were severely contaminated by heavy metals as a result of wastewater irrigation from the tailing pond. The following clean water irrigation for 2 decades produced marked rinsing effect, especially on Pb and Zn. Paddy fields continuously irrigated with wastewater ever since mining started (50 years) had 1,050.0 mg kg^?1 of Pb and 810.3 mg kg^?1 of Zn for upper 20 cm soil, in comparison with 215.9 mg kg^?1 of Pb and 525.4 mg kg^?1 of Zn, respectively, with clean water irrigation for 20 years. Rinsing effect mainly occurred to a depth of upper 40 cm, of which the soil contained highest metals. Copper and Cd in the farmlands were also reduced due to clean water irrigation. Higher availability of Pb might partly account for more Pb transferred from the tailing pond to the farmland and also more Pb removal from the farmland as a result of clean water irrigation. Neither rice in the paddy field nor dense weeds in the uncultivated field largely took up the metals. However, they might contribute to activate metals differently, leading to a different purification extent. Rotation of rice and weed reduced metal retention in the farmland soil, in comparison with sole rice growth. Harvesting of rice grain (and partially rice stalk) only contributed small fraction of total amount of removed metal. In summary, heavy metal in paddy field resulted from irrigation of mining wastewater could be largely removed by clean water irrigation for sufficient time.     

基于网格GIS的安徽省旱涝组合风险区划

依据自然灾害风险形成原理,综合考虑安徽省自然和社会经济状况,从致灾因子的危险性、承载体的暴露性和脆弱性、防灾减灾能力四个方面选取指标,利用自然灾害风险指数法、熵组合权重法以及加权综合评价法建立安徽省旱灾风险指数和涝灾风险指数评价模型。并运用GIS空间分析技术与格网GIS技术绘制出安徽省旱涝组合风险区划图。研究发现,安徽省西北部、中部旱涝组合风险较高,西南部和东北部旱涝组合灾害风险较低,这与安徽省旱、涝灾害历史资料基本吻合,该研究结果可以作为安徽省旱涝综合灾害管理的理论依据。     

When do emotionally exhausted employees speak up? Exploring the potential curvilinear relationship between emotional exhaustion and voice

Two studies were conducted to address the potential nonlinear relationship between emotional exhaustion and voice. Study 1 developed and tested a model rooted in conservation of resources theory in which responses to emotional exhaustion are determined by individual‐level and group‐level conditions that influence the perceived safety and efficacy of voice and drive prohibitive voice behaviors by giving rise to either resource‐conservation‐based or resource‐acquisition‐based motivation. Specifically, there was a curvilinear (U‐shaped) relationship between emotional exhaustion and prohibitive voice under conditions of (i) high job security and (ii) high interactional justice climate, but a linearly negative relationship when these resources were low. Study 2 replicated and extended these findings to include an empirical examination of these effects on promotive versus prohibitive voice. Results confirmed the findings of Study 1, provided evidence of differences in the nomological networks of promotive and prohibitive voice, and indicated that prohibitive voice is more salient to the experience of high emotional strain. Implications of the findings and areas for future research are discussed. Copyright © 2014 John Wiley & Sons, Ltd.     

Molecular evidence reveals the distinctiveness of Indo-Pacific finless porpoises (Neophocaena phocaenoides) in the Pearl River Estuary and insights into genus Neophocaena’s origin

Much of the knowledge about the wide-ranging finless porpoise species (Neophocaena phocaenoides) remains limited, as well as its phylogenetic relationship with another taxa (N. asiaeorientalis) in genus Neophocaena. Using 11 microsatellite loci, we first investigated population differentiation of N. phocaenoides within the Pearl River Estuary (PRE). We then used mtDNA control region (CR) and cytochrome b (cyt b) sequences from the PRE population (75) as well as those from other geographic populations to reveal the divergence level and phylogeny of the PRE N. phocaenoides. Pairwise F _ST analysis with mtDNA CR sequences determined that the PRE population was highly differentiated from other putative populations (with the closest population 400-km away in the Taiwan Strait) (F _ST = 0.388–0.764, p < 0.01). The level of genetic divergence between the PRE and its conspecific population was as high as comparisons between the two subspecies under N. asiaeorientalis (F _ST = 0.361, p < 0.01). Our results also revealed contrasting demographic histories between the PRE and the other geographic finless porpoise populations (the Taiwan Strait population, the southern and northern Yellow Sea population and the middle Yangtze River population), which suggested stability in the warmer waters of the Indo-Pacific and expansions in the colder waters of the North Pacific. Phylogenetic trees created using cyt b data indicated that some haplotypes exclusive to the PRE population were basal to the rest of the genus. Based on these results, we argue that the genus Neophocaena originated in tropical waters (because the PRE is the most southern location sampled, i.e., the closest location to tropical waters).     

山西太谷农村薪柴和蜂窝煤颗粒物和多环芳烃排放特征研究

测定并计算了太谷农村蜂窝煤和薪柴两种燃料颗粒物、CO、CH4和多环芳烃排放因子,其中多环芳烃包括16种美国环保局优控化合物、12种非优控母体多环芳烃、12种硝基多环芳烃和4种含氧多环芳烃.蜂窝煤4类多环芳烃化合物的排放因子分别为3.56±5.42、0.73±0.099、0.22±0.48和0.36±0.62 mg·kg-1,薪柴为62.6±41.3、20.4±3.61、4.44±6.18和0.84±1.00mg ·kg-1.薪柴大多数污染物排放因子高于蜂窝煤,但蜂窝煤多环芳烃排放因子的变异则高于薪柴.蜂窝煤和薪柴多环芳烃排放因子的成分谱有显著差异,除菲、荧蒽和苯并(b)荧蒽为共同优势排放物外,萘、芴、屈和苯并(k)荧蒽为蜂窝煤的特征排放物,芘、环戊烯(c,d)芘和苯并[a]蒽为薪柴的特征排放物.3-硝基荧蒽与3-硝基菲和2-硝基萘分别是蜂窝煤与薪柴排放的主要硝基多环芳烃.母体多环芳烃排放因子的气固比主要受分子量(挥发性)影响,衍生多环芳烃则与取代基的性质有关.蜂窝煤燃烧前期母体多环芳烃的排放因子显著高于后期,两个阶段的总排放因子分别为9.52±12.3和2.54±2.42 mg· kg-1,衍生多环芳烃在两个阶段的差别小于母体多环芳烃.     

地下天然气储气井的现状与前景

储气井是一种压力容器,也是地下压力容器的典型代表。由于开发储气井的理念来源于油气井,因此储气井具有常规压力容器所不具备的特性并存在很多先天不足。文章针对储气井的现状,剖析了储气井在材料、设计、制造、检验检测等各环节存在的问题,并对储气井的健康发展提出了改进建议。     

浙西南食用菌的可持续利用与生态环境研究

近十年来,食用菌在浙西南山区发展迅猛,大大促进了当地农村经济的发展,为农民脱贫致富发挥了重要作用,但也存在着一些问题。针对食用菌生产对生态环境的影响,作者提出了浙西南山区持续发展食用菌的若干建设和对策。     

彩色夹心板在噪声治理中的应用

在噪声治理中,采用彩色夹心板作隔声构件,在武汉总厂涂装分厂制冷站应用成功,用响度指数这个绝对数表示,治理前后噪声总响度降低79.65%,隔声效果非常好,达到了预期的目的.     

某市热电厂输煤系统粉尘治理效果评价

采用湿式作业 ,安装除尘器及自动挡板等方法对输煤系统粉尘进行治理 ,取得良好效果。