广西桂东北地区农业土壤环境若干重金属元素背景值的调查

应用分层抽样统计方法,调查研究广西桂东北地区农业土壤环境Cu、Zn、Pb、Cd、Ni、As、Cr、Hg等8种重金属元素背景值,并分别求算出各元素背景值95％的置信区间。经方差分析,各成土母质间几种元素背景值都有不同程度差异。探讨了该区域农业土壤元素背景值与世界土壤、地壳丰度和国内土壤元素背景值的差异,为开展农业环境科学研究提供依据。     

中空纤维微滤膜污染及阻力分析

选用0．1μm的PVDF中空纤维内压式微滤膜组件，在死端微滤工况下，研究了酵母（平均粒径5．3μm）和高岭土（平均粒径0．7μm）体系在浓度和压力变化时的污染机理及过滤阻力、膜渗透通量的变化规律性。通过恒压堵塞定律积分式的具体形式与实验数据的拟合及根据堵塞过滤定律计算的结果都表明：死端微滤时，酵母体系和高岭土体系均符合滤饼过滤机理。     

三种偶氮染料降解历程在紫外-可见光谱上的表现

本文对基本结构相似的三种偶氮染料橙黄Ⅱ、活性艳红Ｘ－３Ｂ和活性黑Ｋ－ＢＲ水溶液在铁粉还原－光氧化两步法处理中的紫外－可见光谱图作对比分析,依据其结构与特征吸收的关系,初步推测还原铁粉－光氧化法降解染料的历程。     

An experimental study on recolonization and succession of marine macrobenthos in defaunated sediment

Hypoxia/anoxia in coastal waters is a world wide problem which often results in mass mortality and defaunation of benthos. In this study, field experiments were carried out to examine recolonization and succession of macrobenthic infauna in defaunated sediments, and the time required for recovery from complete defaunation to a stable community. Trays (33 cm length × 25.5 cm width × 11 cm depth) of defaunated sediment were exposed at the subtidal of a pristine site in subtropical Hong Kong. Temporal changes of macrobenthic communities in defaunated sediment were analyzed by univariate and multivariate statistics, and compared with those in undisturbed natural sediment at the same site. Initial colonization of macrobenthos occurred rapidly. A total of 42 species was found, with an average of 258 animals per tray and 24 species per tray recorded in the first month. Abundance showed a small peak (496 animals per tray) after 3 months, reached a sharp peak (1154 animals per tray) after 6 months, and declined thereafter. Species number increased gradually, reached a maximum (68 species per tray) after 9 months, and then decreased. Recolonization was predominantly contributed by larval settlement rather than adult migration. Temporal changes in abundance, species number and diversity of the macrobenthic community in defaunated sediment resemble the spatial changes along a decreasing pollution gradient previously defined by other authors. Results of this experiment suggest that newly available sediment may allow more species to colonize (or coexist) than sediment pre-occupied by an established community. This is probably due to less interspecific competition in the former habitat. No significant difference in abundance or species richness was observed between defaunated and natural sediments after 15 months, suggesting that a stable community had been achieved, although minor variations in species composition were still discernible between defaunated and natural sediments. Received: 24 May 1999 / Accepted: 20 October 1999     

聚苯乙烯基硫代磺酸钾树脂的合成及其与卤代烃的反应

由聚苯乙烯基磺酰氯树脂与硫化氢钾反应制备聚苯乙烯基硫代磺酸钾树脂（Ｉ）,树脂Ｉ与亲电的卤代烃反应,生成聚苯乙烯基硫代磺酸酯树脂（Ⅱ）,树脂Ⅱ经过乙硫醇处理,使卤代烃结构部分以不对称二硫醚的形式游离下来,用ＧＣ／ＭＳ对其结构进行鉴定。从不对称二硫醚的结构可推导出原卤代烃的结构,所制备的聚苯乙烯基硫代磺酸钾树脂的转化效率为１．１１ｍｍｏｌ·ｇ＾－１。     

羊角月芽藻摄取磷形态的动力学研究

将湖水中的磷分成总溶解磷,溶解反应磷,总反应磷、溶解的水解性磷,溶解的光解性磷。研究其在羊角月芽过程中的变化。     

偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附

以腈纶纤维为原料络合Fe3+制得偕胺肟合铁(Ⅲ)纤维,用其处理α-萘酚溶液,研究了偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附工艺条件和吸附动力学参数。实验结果表明,偕胺肟合铁(Ⅲ)纤维对α-萘酚的最佳吸附工艺条件为pH=3.0、吸附温度313.15K和吸附时间45min。在最佳工艺条件下,偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附在所研究的α-萘酚浓度范围内符合Freundlich等温吸附方程。未达到饱和吸附前,偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附符合一级反应动力学特征。     

废纸苯酚液化物合成热固型酚醛树脂

为了提高废纸的附加值,利用废纸苯酚液化物与甲醛在碱性环境中反应,进行热固型酚醛树脂合成实验。通过正交实验确定最优化的树脂化合成工艺为:n(甲醛)∶n(废纸液化物)=2.1,n(氢氧化钠)∶n(废纸液化物)=0.5,合成温度74℃,合成时间3.0h。在此工艺条件下制备的酚醛树脂压制的胶合板达到GB/T9846—2004《人造板及饰面人造板理化性能试验方法》中Ⅰ类胶合板的强度要求。     

核电安全

<正>2010年6月16日国家核安全局有关负责人向媒体通报,大亚湾核电站二号机组反应堆中的一根燃料棒包壳出现微小裂纹,其影响仅限于封闭的核反应堆一回路系统中,放射性物质未进入环境,未对环境造成影响和损害。该负责人指出,大亚湾核电站二号机组核反应堆一回路冷却     

磁絮凝处理废水工艺条件的响应曲面法优化研究

以聚硅硫酸铁(PFSS)为絮凝剂、磁流体为磁种,采用磁絮凝法处理模拟废水。在正交实验基础上,利用Matlab软件进行响应曲面分析,研究磁絮凝法处理模拟废水的各因素间具有的交互作用关系。回归拟合结果表明最佳工艺条件为:PFSS加入量36.8g/L,模拟废水pH7.4,磁种加入量14.7mg/L,搅拌转速266r/min。在最佳工艺条件下进行实验,TP去除率为97.70%。