磺胺嘧啶和盐酸四环素对四种赤潮藻生长的影响

本文以锥状斯氏藻（Scrippsiella trochoidea）、米氏凯伦藻（Karenia mikimotoi）、球形棕囊藻（Phaeocystis globosa）、中肋骨条藻（Skeletonema costatum）为研究对象,实验室条件下对比研究了磺胺间二甲氧嘧啶钠（SMS）和盐酸四环素（TC）暴露下4种赤潮藻的细胞增长、光合色素组成以及最大光能转化效率（Fv/Fm）等的变化规律。研究结果表明:4种赤潮藻在SMS和TC（7.5～240 mg/L）暴露组细胞密度均未出现半抑制效应,SMS对4种赤潮藻细胞密度的最大抑制效应范围为5.47%～36.26%,略高于TC的最大抑制效应0～35.21%（球形棕囊藻无抑制效应）;藻细胞叶绿素含量在抗生素暴露下均显著下降,但作为抗氧化剂和捕光色素的类胡萝卜素含量则显著增加;低浓度（<50 mg/L）TC暴露下,4种赤潮藻Fv/Fm均显著下降;TC（<30 mg/L）暴露下,4种赤潮藻细胞密度最大促进作用范围为11.30%～38.89%,球形棕囊藻细胞密度增加比例最高;赤潮藻对抗生素的响应存在显著的种间差别,两种抗生素暴露对球形棕囊藻生长的抑制效应明显低于其他3种赤潮藻,高浓度抗生素残留对浮游植物群落演替存在较强的干扰作用。     

Highly Oriented Thermoplastic Poly (vinyl alcohol) Films by Uniaxial Drawing: Effect of Stretching Temperature and Draw Ratio

Journal of Polymers and the Environment - With the advantages of excellent processability and biodegradability, polyvinyl alcohol (PVA) becomes an environmentally friendly and biocompatible...     

“象牙塔”精神与大学“社会化”之辩证融合

通过分析＂象牙塔＂精神和大学＂社会化＂的科学内涵,揭示了二者的合理性共生关系。要使＂象牙塔＂精神和大学＂社会化＂辩证融合,促进大学在实践中既崇尚学术又适应社会,应该走倡扬、培育＂象牙塔＂精神并让大学承担起应有的社会责任的路径。     

浑河流域底栖动物生物完整性指数构建与健康评价

应用大型底栖动物生物完整性指数(Benthic Index of Biological Integrity, B-IBI)评价河流健康已成为河流生态系统管理的重要方法。根据2010年5月对浑河流域62个采样点的底栖动物调查数据,基于采样点的水质等级、栖息地质量综合评估指数、人类干扰强度和河岸土地利用评估等标准,选择同属于辽河水系的太子河流域的8个采样点作为参照点,构建浑河流域B-IBI生物完整性指数。通过对34个生物参数的分布范围检验、判别能力分析以及相关性检验,最终确定浑河流域B-IBI生物完整性指数由总分类单元数、EPT(蜉蝣目Ephemeroptera、襀翅目Plecoptera、毛翅目Trichoptera)相对丰度、耐污类群相对丰度、最优势类群分类单元数、直接收集者相对丰度以及香农威纳多样性指数6个参数构成。根据各参数值随干扰增强的变化趋势,采用比值法计算各指标的分值和评价标准。结果表明:浑河流域B-IBI平均得分为2.56,河流健康状态处于一般状态;62个采样点中,9个处于健康状态,13个处于亚健康状态、22个处于一般状态、10个处于差状态,8个处于极差状态;从流域空间尺度上来看,河流健康状态从上游区到下游区逐渐变差。相关性分析表明,B-IBI与水温、电导、溶解性固体总量、硝酸盐、总氮、五日生化需氧量等水环境指标呈现显著负相关,表明B-IBI指数对于水质污染具有较好的指示性作用。综上所述,浑河流域由于受城市工业区的分布影响,大型底栖动物生物完整性呈现出明显的空间分布差异,上游区河流生物完整性较好、中下游底栖动物群落呈现出明显的退化趋势。     

铝塑包装废物热解过程能量平衡分析

热解是实现铝塑包装废物中有机物和金属铝分离的有效方法。利用外热式固定床反应系统对其进行热解实验,研究热解时物质与能量流向的变化趋势。结果表明:(1)铝塑包装废物最佳热解温度为723～773 K;(2)热解产生的可回收能量远大于反应所需能量,可以实现热解系统的自供热;(3)铝塑包装废物热解的净能源回收效率为62%～63%。     

一株脱硫菌的分离及脱硫动力学

从污水处理厂二沉池分离获得一株硫酸盐还原菌厌氧菌株,依据生理生化分析和16S rDNA基因序列测定该菌株被鉴定为脱硫脱硫弧菌(Desulfovibrio desulfuricans)。在气体吸收的双膜理论和液相中微生物转化的米门方程基础上,建立了搅拌式生物吸收反应器中脱硫脱硫弧菌净化二氧化硫气体的动力学模型,并求解出相应的动力学参数基质转化最大速度Vmax和米氏常数Km,实验结果所得到的线性方程相关性较好,线性相关系数可以达到0.998,而且脱硫脱硫弧菌吸收液具有较高转化二氧化硫的能力。     

Assessing the visual quality of green landscaping in rural residential areas: the case of Changzhou, China

Changzhou is a typical waterside municipality with approximately 2,500 years of history located south of the Yangtze River. It was an agriculturally oriented region but is becoming an industrialized region. Rural green landscaping in this region possesses characteristics of traditional Chinese gardens. This paper presents a methodology for assessing the visual quality of green landscaping in rural residential areas through public perception-based and expert/design approaches. The former approach enables us to rank green landscaping based on a survey of public preference; the latter weighs the contributions of the attributes contained in a photograph to its overall scenic beauty via correlation, regression, and factor analyses. The photographs used in the survey included road greenways, riparian greenways, residential public gardens and green landscaping around houses, with each type of landscape represented by seven photographs. In total, 141 college students and 41 other participants ranked photographs of each landscaping type from highest to lowest preference. The results indicate that the preferences of students are similar to those of the general public. Examples of green landscaping depicted in the “best” four photographs possessed more attractive qualities regarding the variety of vegetation, richness of colors and a selection of human additions compared to those depicted in the “worst” photographs. The perceived visual quality was positively influenced by, in decreasing order of importance, the variety of vegetation, color contrast, the openness of green spaces, the area of vegetation, and positive man-made elements; conversely, it was negatively influenced by the type of topography. Moreover, some suggestions were offered for future rural greening regarding perceived visual beauty.     

新型材料处理化学镀镍废水

采用一种同时具备吸附和离子交换功能的新型材料CARBONITE对低浓度化学镀镍废水进行实验研究,分别探讨了CARBONITE用量、pH值、温度和反应时间对CARBONITE去除废水中Ni2+的影响,并考察了CARBONITE的再生性能。实验结果表明,当CARBONITE投加量为1.5 g/L,pH值为6.8,温度为40℃,反应时间为6 h时,CARBONITE对Ni2+去除率可达最大值91.39%。用pH值为4的硫酸溶液对吸附后的CARBONITE进行再生实验,效果良好,再生3次之后的CARBONITE对Ni2+的去除率仍能达到82%左右。     

Fenton氧化-前置反硝化缺氧好氧池(A/O)处理荧光增白剂废水中试研究

采用Fenton氧化-前置反硝化缺氧好氧池(A/O)对荧光增白剂废水IC出水进行中试实验研究。实验表明,在Fe2+投加量为0.003 mol/L,进水pH值为3,[H2O2]/[Fe2+]为4∶1,反应时间为2 h的条件下,Fenton氧化法对COD的去除率可以达到46%以上,出水BOD5/COD的值由0.26提高到0.58。氧化后废水进入前置反硝化生物脱氮系统进行生化处理,该系统采用间歇式进水,水力停留时间为2 d,实验结果表明,A/O系统对COD、氨氮和总氮的去除率分别达41%、90%以上和86%。该组合工艺对COD的总去除率可达到67%,出水氨氮在20 mg/L以下,总氮在37 mg/L以下。     

Climate Change Adaptation Among Tibetan Pastoralists: Challenges in Enhancing Local Adaptation Through Policy Support

While researchers are aware that a mix of Local Ecological Knowledge (LEK), community-based resource management institutions, and higher-level institutions and policies can facilitate pastoralists' adaptation to climate change, policy makers have been slow to understand these linkages. Two critical issues are to what extent these factors play a role, and how to enhance local adaptation through government support. We investigated these issues through a case study of two pastoral communities on the Tibetan Plateau in China employing an analytical framework to understand local climate adaptation processes. We concluded that LEK and community-based institutions improve adaptation outcomes for Tibetan pastoralists through shaping and mobilizing resource availability to reduce risks. Higher-level institutions and policies contribute by providing resources from outside communities. There are dynamic interrelationships among these factors that can lead to support, conflict, and fragmentation. Government policy could enhance local adaptation through improvement of supportive relationships among these factors. While central government policies allow only limited room for overt integration of local knowledge/institutions, local governments often have some flexibility to buffer conflicts. In addition, government policies to support market-based economic development have greatly benefited adaptation outcomes for pastoralists. Overall, in China, there are still questions over how to create innovative institutions that blend LEK and community-based institutions with government policy making.