Some characteristics of the distribution of heavy metals in urban topsoil of Xuzhou,China

An assessment is presented of distribution characteristics of heavy metals in the urban topsoil from the city of Xuzhou. The concentrations of Ag, Al, As, Au, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Ga, Hg, Li, Mn, Mo, Ni, Pb, Pd, Pt, Sb, Sc, Se, Sn, V and Zn have been determined from 21 soil samples. Examination of lognormal distribution plots indicates that the diagrams of Al, Be, Fe, Ga, Li, and V are almost linear suggesting that these metals are almost unaffected by anthropogenic activities while the plots for As, Cd, Cu, Pb, Pd, Pt, Se, Zn and others are not linear probably due to anthropogenic activities from which these metals are delivered to the soils. Al is used for mineralogical normalization of these data. An evaluation of background values for topsoil is also carried out by means of lognormal distribution plots. The results show our background values obtained from the lognormal distribution plots are comparable to those values of uncontaminated soils of Xuzhou obtained by previous work except for Cd and Hg. At present, no explanation for the exceptions Cd and Hg can be given.     

悬浮法聚氯乙烯化工离心母液的生化处理中试

采用4级内循环式好氧生物膜反应器串联工艺对悬浮法聚氯乙烯(PVC)离心母液废水进行中试试验,研究了不同停留时间下系统对有机物和浊度的处理效果以及系统的抗冲击能力;观察了生物膜的生长和发展规律;对影响系统稳定运行的主要因素(悬浮物、摇蚊幼虫和营养物)进行了分析,并提出了相应的控制措施.试验结果表明:该工艺启动迅速,在HRT为14h时,废水COD总去除率可达75%以上,出水COD浓度低于50mg/L ,完全可以达到排放标准,也可经深度处理回用于生产.     

Investigation of natural VOC emitted from tropical vegetations in China

Twenty-three kinds of typical plants in Xishuangbanna, the tropical area of southwestern China, were screened to estimate the emission rates of isoprene and monoterpenes by adopting bag-enclosure and curette sampling methods followed by a GC-FID analysis. It was found that the Ficus species were mainly emitting isoprene and most tropical vegetations were mainly releasing monoterpenes. The results also showed that the emissions of isoprene were affected by both temperature and PAR( Photosynthetic Active Radiation), while monoterpene emissions were mainly temperature-dependent.     

酯类化合物对四膜虫毒性的拓扑研究

提出了拓扑方法,即考虑分子图顶点的性质,直接用酯类化合物的分子碎片的特征值为主元来构建邻接矩阵。定义并计算了酯类化合物的修正的氢连接性指数^mHA及其倒指数^mHB,分析了30个酯化合物对四膜虫的毒性与分子结构之间的关系,结果表明由酯化合物对四膜虫毒性与^mH的回归方程得出的估算值与实验测定值之间能较好地吻合,平均误差为0．22。     

荷电水雾除尘器捕尘效率的实验研究

实验分析了影响荷电水雾除尘器除尘效率的主要因素,在此基础上提出了一种新的除尘效率数学模型,该模型明确地表达了过滤风速、喷雾量以及雾滴荷质比对除尘效率的贡献情况。对实验结果及数学模型的分析表明,对于带有振弦栅的荷电水雾除尘系统,喷雾量对除尘效率的影响比过滤风速及荷质比更为显著,新除尘效率模型的提出对指导生产具有重要意义。实验中同时确定了荷电水雾除尘器最佳操作参数,在粉尘入口浓度为412 mg/m3的情况下,当过滤风速为16 m/s,喷雾量为12×10-3 m3/min,雾滴荷质为3.5×10-4 c/kg时,除尘效率可达99.5%。     

基于GFI模型的工业能源强度变动因素分解研究

在前人研究的基础上,核算了2001-2010年天津市34个工业行业的能源强度,利用GFI(Generalized Fisher Index)模型将能源强度的变动分解为技术进步、能源结构和产业结构3个因素.结果表明,从逐年各因素效应的累积值来看,产业结构对天津市能源强度变动的影响最大,其次是能源结构,技术进步的影响较小;在各因素效应值的波动方面,能源结构与技术进步对能源强度变动的影响波动较小,产业结构的影响效应值波动较大.从产业结构的角度来看,天津市2001-2010年重工业产值的增加快于轻工业,二者的差距逐渐加大,这种态势抑制了能源强度的降低;从技术进步的角度来看,由于绿色生产技术的广泛使用,天津市重工业与轻工业的单位产值能源消耗都呈下降趋势.因此,天津市进一步降低能源强度的重点还应该放在产业结构调整方面,发展绿色产业,促进产业升级;同时,不能忽视能源结构和技术进步因素的作用,大力发展绿色能源和新能源,推广清洁生产技术.     

On Uncertain Sightings and Inference about Extinction

The extinction of many species can only be inferred from the record of sightings of individuals. Solow et al. (2012, Uncertain sightings and the extinction of the Ivory‐billed Woodpecker. Conservation Biology 26: 180–184) describe a Bayesian approach to such inference and apply it to a sighting record of the Ivory‐billed Woodpecker (Campephilus principalis). A feature of this sighting record is that all uncertain sightings occurred after the most recent certain sighting. However, this appears to be an artifact. We extended this earlier work in 2 ways. First, we allowed for overlap in time between certain and uncertain sightings. Second, we considered 2 plausible statistical models of a sighting record. In one of these models, certain and uncertain sightings that are valid arise from the same process whereas in the other they arise from independent processes. We applied both models to the case of the Ivory‐billed Woodpecker. The result from the first model did not favor extinction, whereas the result for the second model did. This underscores the importance, in applying tests for extinction, of understanding what could be called the natural history of the sighting record. Sobre Avistamientos Inciertos e Inferencia de la Extinción     

江苏省乡村性空间格局及影响因素研究

基于城乡一体化思想,在分析乡村性内涵基础上,采用人口密度等指标构建乡村性评价体系,以全国第五、六次人口普查等数据为基础,借助SPSS、ArcGIS、Geoda软件,探讨了江苏省县域单元乡村性空间格局及影响因素。结果表明：(1)2000～2010年,江苏全省县域单元乡村性逐渐减弱,并呈现出阶梯状的空间分布态势;(2)各县域乡村性指数并不表现为完全随机状态,而是存在显著的正空间相关性。热点区域分布在沭阳县与泗阳县交界处为核心的圈层结构,冷点区域集中在乡镇工业发达的苏锡常地区;（3）社会环境、交通、资本、工业化和城市化、政策等因素是乡村性变化的主要影响因素;（4）未发现乡村性加强的现象;在数据可获得情况下,以乡镇为单元研究乡村性将具有更强的现实指导意义     

淄博市涂装行业VOCs排放水平及减排潜力

为了评估淄博市涂装行业的挥发性有机物（VOCs）排放水平和减排潜力,对3个具有代表性的涂装行业：汽车制造涂装行业、木制家具涂装行业和金属表面涂装行业的8个典型企业展开实地调研;在此基础上采用实测法、物料衡算法和排放因子法核算企业的VOCs排放量,建立本地化排放因子,并与包括AP-42在内的国内外其他研究进行对比,评估企业排放水平;基于物料衡算法核算减排潜力;并采用显著性差异分析法研究各环节管控的影响程度.结果表明,淄博市汽车制造行业VOCs的排放因子为4.38 kg ·辆^-1,木制家具涂装行业的排放因子（以涂料计）为212.52 g ·kg^-1,金属表面涂装行业的排放因子（以涂料计）为42.79 g ·kg^-1;家具企业C的源头减排潜力及金属G和F的过程减排潜力能够达到50%以上;各环节管控的影响程度从高到低依次为：源头>过程>末端.     

不同土壤-小麦体系中铅镉交互作用与转运特征

选用海伦黑土、咸宁棕红壤和长武黑垆土这3种土壤,分别设置4组不同含量配比的Pb和Cd复合处理,进行为期5个月的小麦种植(郑麦9023号)盆栽试验,结合小麦植株各部位Pb和Cd含量,分析3种土壤-小麦体系中Pb和Cd交互作用对小麦富集转运重金属的影响.结果表明,低pH棕红壤水溶态Cd和Pb含量最高,且土壤颗粒表面Pb和Cd交互作用显著,高有机质黑土及高碳酸钙含量的黑垆土中Cd和Pb活性较低.3种土壤中黑垆土种植小麦的株高和干重表现最差,但Pb和Cd复合作用使其株高较对照增加了2.68～8.49 cm, Pb和Cd交互作用对黑土中小麦的株高和干重影响最小,但抑制了棕红壤中小麦生长.3种土壤-小麦体系的Pb和Cd交互作用差异较大,棕红壤中Pb和Cd间存在协同作用,125 mg·kg^-1和250 mg·kg^-1Pb处理下棕红壤种植的小麦籽粒Pb含量随Cd添加量升高分别显著增加73.2%和19.1%;黑土中Pb和Cd间存在拮抗作用,0.3 mg·kg^-1和0.6 mg·kg^-1 Cd处理下黑土中小麦籽粒Cd含...