土壤有机质测定方法的进展

对土壤有机质测定的3种主要方法及特点和应用范围进行了论述和评价。认为上壤有机质测定方法改进的目标不仅仅是简便、快速、廉价,还应包括无污染。     

掺杂La3+纳米ZnO的制备及其光催化性能

采用共沉淀法制备了不同La3＋含量的La3＋-ZnO催化剂,采用x射线衍射仪、透射电子显微镜等对催化剂的结构、相组成、形貌和粒径进行了表征,比较了不同La3＋含量的La3＋-ZnO催化剂对罗丹明B降解率的影响。实验结果表明,掺杂La3＋导致ZnO粒径减小,比表面积增大,延长了光生电子-空穴对的寿命,提高了ZnO的光量子产率,La3＋-ZnO催化剂的光催化活性比ZnO显著增强。La3＋质量分数为0．8％时,罗丹明B降解率最高,为92．5％。经La3＋质量分数0．8％的La3＋-ZnO催化剂降解后罗丹明B已被完全降解为无机小分子。     

苏门答腊海域海啸地震及地壳深部结构

近10年来苏门答腊俯冲带大震频发,并引发灾难性海啸,使之成为全球关注的焦点。特别是2004年和2012年的两次大震所带来的科学问题在许多方面超出现有认识。国际上对苏门答腊地区已开展了大量的地质学、地球物理学等多方面的调查研究,应用了许多新方法并取得了许多新认识。解读苏门答腊的构造背景和地质演化史对于认识俯冲型大地震的产生机理是必要的,对此类地震的发生过程和规律的研究,对于理解海啸产生的条件和防灾减灾有十分重要的现实意义。本文对苏门答腊地区的地震活动和深部构造进行了详细分析,对近年关于该地区的世界性研究成果进行了总结,梳理出若干亟待研究的科学问题,进而提出开展苏门答腊俯冲带地震3D层析成像的具体实施路线。     

烟根腐解物对烟草生长的影响

烟草生产过程中会产生大量烟草残体,为了研究烟草残体对烟草生长的影响,将烟根、水稻土和无菌水按一定比例混合后,在适当条件下培养得到烟根腐解物.将烟根腐解物按不同的施用量设置6个处理组,并以未施用烟根腐解物组作为对照,分别在烟草生长的团棵期、旺长期和成熟期测定烟草的农艺性状、根系活力、硝酸还原酶(nitrate reduc...     

Toxicological assessment of TiO2 nanoparticles by recombinant Escherichia coli bacteria

Rapid and efficient methods to assess nanoparticle toxicity are desired in current research. Here we showed that Escherichia coli labeled by green fluorescent protein can be a good model bacterium for assessing acute toxicity of TiO(2) (about 50% inhibition ratios after 135 min exposure). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that TiO(2) nanoparticles (NPs) can influence certain protein expression in the recombinant bacterium, and the obvious effects in repressed expression and elevated expression were observed in 30/40, 10/20 μg mL(-1) treated cells, respectively. However, the GFP expression (27 kD) was not influenced by introduced TiO(2) NPs. The change of the fluorescence intensity may be caused by the damage in folding and chromophore formation of the GFP post-translational modification due to generated reactive oxygen species. Furthermore, TiO(2) NPs at higher concentrations decreased their toxicity because of aggregation. 20 μg mL(-1) humic acid (HA) introduced to the medium can decrease the fluorescent inhibition owing to the barrier of steric hindrance it provides between NPs and cells.     

Impact of elevated O3 on visible foliar symptom, growth and biomass of Cinnamomum camphora seedlings under different nitrogen loads

The effects of elevated ozone (O(3)) and enhanced nitrogen (N) on the growth and biomass of Cinnamomum camphora, a subtropical evergreen broad-leaved tree species, were investigated. The seedlings, supplied with N (NH(4)NO(3) solution) at 0, 30 and 60 kg ha(-1) year(-1) (simplified as N0, N30, N60, respectively), were exposed to ambient (AA) or elevated O(3) (AA + 60 nmol mol(-1) and AA + 120 nmol mol(-1), designated as AA + 60 and AA + 120, respectively) for the 2009 and 2010 growing seasons. Symptomatic leaf percentages were significantly increased with O(3) concentration. AA + 120 significantly decreased the mean leaf size and chlorophyll content of both 2009- and 2010-emerged leaves, inhibited the growth of stem height and basal diameter, and reduced biomass accumulation of all plant parts except for leaves. By comparison, only the chlorophyll content of 2009-emerged leaves and root dry weight were significantly reduced under AA + 60. Specific leaf area, total leaf area and foliar biomass were not affected even at a higher O(3) level. On the other hand, N loads, especially N60, exerted significantly positive effects on all variables except mean leaf size and shoot/root ratio. No significant interactions between O(3) and N were detected, suggesting that the N supply at ≤60 kg ha(-1) year(-1) did not significantly modify the response of C. camphora to O(3) in terms of seedling growth and biomass accumulation.     

医疗废物处置工艺改进及运行效果研究

随着医疗废物产生量快速增长,造成了大气、水体、土壤的严重污染。医疗废物无害化处理成为我们当前急需解决的迫切问题。通过对垃圾处置厂医疗废物高温蒸汽处置工艺的研究,在现有工艺仅可处理感染性和损伤性废物的基础上,进行技术改进,通过增加蒸汽骤冷环节,从而增加了对病理性废物处置类别,并能确保环保及卫生达标;同时提高了灭菌率,减容率。设备改进后,可有效地处理病例性废物,有效地减少对环境的污染。     

建设项目竣工环境保护验收监测的工作程序和问题思考

简要介绍了建设项目竣工环境保护验收监测的工作程序,并结合工作实际,对验收监测中遇到的几个问题进行阐述,以利于建设项目竣工验收。     

自助加油站典型事故案例分析及防范措施

分析了自助加油站面临的主要安全风险,针对自助加油站的非静电类典型事故案例进行了分析和讨论。在参考和借鉴国外自助加油站相关法规的基础上,提出了一系列有针对性的防范措施。