青鳉鱼的行为特征提取研究

采用生物行为传感器获取青鳉鱼的行为数据时,青鳉鱼个体差异会导致采集到的原始电信号在时空特性下完全不同。重要的行为特征往往被隐藏在原始信号中,传统的信号处理方法无法实时而有效地提取到这些特征。针对这个问题,观察并记录了暴露实验前后青鳉鱼的行为变化,提出了一种可以高效表征行为特征的直方图统计算法。实验结果表明,该方法能够准确对应人眼观测到的暴露实验前后鱼的行为变化趋势,同时也为后续异常行为识别提供一定的支持和参考。     

Development and preparation of lead-containing paint films and diagnostic test materials

Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.     

空气质量监测中现场空白测定方法探讨

探讨了空气质量监测中现场空白的测定方法,通过对封口的现场空白与实验室对白比对及采样过程现场空白吸收管开口与封口对照试验,认为采样时应对现场空白吸收管作封口处理,才能体现现场空白的真实性。     

Assessment of urban stream morphology: an integrated index and modelling system

Physical morphology is an important attribute of a stream system. The morphological state of a natural pristine stream often reflects its biological condition because of their close links. In contrast, the morphology of an urban stream may exhibit different behaviours due to serious human disturbances. For an urban stream system, the morphological condition not only determines the in-stream habitat quality but also provides the physical basis for the stream’s municipal functionalities. By comparing the morphological characters of urban and natural streams, this paper develops an integrated index system and model for the assessment of urban stream morphology. The model is applied to the Ancient Canal (Zhenjiang, China) with the aim of comparing the morphological conditions of reaches with and without ongoing restoration programs and further of assessing the effectiveness of the restoration methods and techniques. The results indicate that the water security and the landscape functionality of the canal have been upgraded. However, the quality of the in-stream habitat has been degraded as a result of the restoration. Based on the modelled results, recommendations are given for improving the effects of the next-phase restoration. The assessment system and findings from the application presented here are expected to have important implications for the restoration of disturbed urban streams in many other cities in China and elsewhere in the world.     

制革废水处理技术探讨

针对制革废水的组成和特点,介绍了制革废水物化预处理技术与生物处理技术研究与应用进展,分析了各处理技术的优点与缺点.     

臭氧氧化法制备晶体乙醛酸的清洁生产工艺

以顺丁烯二酸酐为原料、水为溶剂,用臭氧氧化法制备晶体乙醛酸的最佳条件为：反应时间8h,反应温度30℃,顺丁烯二酸质量分数30％。减压蒸馏出的甲酸水溶液可循环利用。中试试验结果表明,合成的晶体乙醛酸中乙醛酸的质量分数为97．2％～97．7％,达到了市售工业乙醛酸的要求。晶体乙醛酸的收率为95．5％-96．1％,熔点为51～53℃,用红外光谱技术对其结构进行表征的结果表明,晶体乙醛酸的红外谱图与乙醛酸标准谱图基本吻合。该工艺过程无三废污染,可实现清洁生产。     

Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta

Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is able to tolerate five model NAs (cyclohexanecarboxylic acid, cyclohexaneacetic acid, cyclohexanepropionic acid, cyclohexanebutyric acid and 1,2,3,4-tetrahydro-2-naphthoic acid) at 300 mg L⁻¹, a level which exceeds that of any single or combination of NAs typically found in tailings ponds. Moreover, we show that D. tertiolecta can metabolize four of the model NAs. Analysis of NA-amended cultures of D. tertiolecta via low resolution gas chromatography-mass spectrometry allowed us to quantify decreasing NA levels, identify metabolites, and formulate putative mechanisms of biodegradation. Degradation of cyclohexanebutyric acid and cyclohexanepropionic acid proceeded via β-oxidation and resulted in the transient accumulation of cyclohexaneacetic acid and cyclohexanecarboxylic acid, respectively. Cyclohexanecarboxylic acid was metabolized via 1-cyclohexenecarboxylic acid suggesting that further degradation may occur by step-wise β-oxidation. When D. tertiolecta was inoculated in the presence of oil sands tailings water from the Athabasca region, biodegradation of single-ring NAs was observed relative to controls. This result corroborates the trend we observed with the single-ring model NAs.     

絮凝剂产生菌B-7的培养条件优化及生长动力学研究

从成都市土壤中筛选分离了1株具有稳定高效的微生物絮凝剂产生菌B-7。考察了碳源、氮源、温度、培养时间、pH等多种因素对絮凝剂（MBF-7）絮凝效果的影响。实验结果表明,该菌株产絮凝剂的最佳培养条件为：碳源为淀粉,氮源为硫酸铵,培养时间为72 h,初始pH为7.0,温度为30℃,对0.4%高岭土悬浊液的絮凝率达到91.3...     

写好科技论文的英文摘要以提高被引率

科技论文英文摘要的编写要遵循一定的内容要求和句法要求。作者和英文编辑应该加强对英文摘要的重视,提高自身的英文水平,通过写好英文摘要来提高论文的被引率和期刊的影响因子。同时,编辑还要发挥对作者编写英文摘要的督促作用。     

广东省水资源可持续利用评价研究

将影响水资源可持续开发利用的主要评价指标组成模糊物元,同时各开发利用阶段作为物元的对象,以各项评价指标及其相应的模糊量值构造复合模糊物元,运用层级分析法(AHP)确定各评价指标的权重,最后计算其欧化距离相似贴近度.通过广东省水资源可持续开发利用评价验证了该分析方法的科学性和有效性.