烟草废水菌群处理及主要污染物降解过程解析

烟草制品加工过程中会产生大量的废水,且含有尼古丁等多种复杂的有毒难降解污染物,如不合理处置,将对环境造成严重的污染并危害人类健康,因而有效处理该类废水是烟草行业中一个亟待解决的技术难题.利用梯度筛选驯化法从环境中获得3组高效处理烟草加工废水的菌群,其中高效菌群C对化学需氧量(COD)的去除率达83.1%,且其他各项指标如色度、氨氮(NH_4~+-N)及磷酸盐(PO_4~(3-)-P)等均明显降低.微生物群落结构分析结果显示,菌群的香农-威纳指数(Shannon-Wiener Index)、辛普森多样性指数(Simpson Index)和菌群丰富度指数(ACE)分别为3.645、0.978、106,表明菌群多样性高,物种构成复杂,分布均匀.菌群C中变形菌门占有最大比例为48.7%,其次为放线菌门,比例为11.5%,并在菌群中检测出多种具有降解杂环芳香化合物、芳烃及酚类等物质的菌种.污染物检测结果证明,菌群处理后污染物整体去除率近90%,其中尼古丁被完全降解,去除率为100%.本研究获得的菌群不仅可以针对性的降解主要污染物尼古丁,且能够全面去除其他污染物,在烟草废水处理领域具有广阔的应用前景.     

水中悬浮物测定影响因素及质量控制措施探讨

重量法是测定水中悬浮物的常用方法。恒重是该法获得有效数据的关键环节。本研究采用重量法测定水中悬浮物,并对滤膜的前处理、冷却时间及称量等操作环节进行了讨论。实验证明严格控制各项影响因素可以有效的提高恒重效率,缩短测定周期。采用空白滤膜作为质量控制措施可减少测定误差。     

装配式摩擦‑软钢耗能支座设计与性能试验∗

结合滑动摩擦耗能及塑性变形耗能机制,设计了一种装配式摩擦?软钢耗能支座。该支座可看作包含摩擦板的滑动摩擦组件与软钢棒的组合,属于一种功能分离式支座。滑动摩擦组件提供了支座的竖向和水平承载力,以及大部分耗能;而软钢棒增强了支座的屈服后水平刚度,有效减小支座滑动位移,破坏后便于更换。利用压剪试验机实测了摩擦?软钢耗能支座的摩擦系数及耗能性能,后者包括滞回曲线、刚度退化曲线、单位滞回耗能及等效阻尼比等指标。最后提出了一种考虑承载能力系数的改进等效阻尼比。试验结果表明：不同竖向荷载下支座的摩擦系数较为稳定,软钢棒与摩擦板共同提供了支座的水平刚度和耗能能力,支座的整体耗能性能良好。     

Rescue effects of Se-enriched rice on physiological and biochemical characteristics in cadmium poisoning mice

Environmental Science and Pollution Research - Cadmium (Cd) is an element injurious for human health and is possibly toxic to organisms at minor concentrations. While some of other trace metallic...     

Characteristics of gas-liquid pulsed discharge plasma reactor and dye decoloration efficiency

The pulsed high-voltage discharge is a new advanced oxidation technology for water treatment. Methyl Orange (MO) dye wastewater was chosen as the target object. Some investigations were conducted on MO decoloration including the discharge characteristics of the multi-needle reactor, parameter optimization, and the degradation mechanism. The following results were obtained. The color group of the azo dye MO was effectively decomposed by water surface plasma. The decoloration rate was promoted with the increase of treatment time, peak voltage, and pulse frequency. When the initial conductivity was 1700 μS/cm, the decoloration rate was the highest. The optimum distance between the needle electrodes and the water surface was 1 mm, the distance between the grounding electrode and the water surface was 28 mm, and the number of needle electrodes and spacing between needles were 24 and 7.5 mm, respectively. The decoloration rate of MO was affected by the gas in the reactor and varied in the order oxygen > air> argon > nitrogen, and the energy yield obtained in this investigation was 0.45 g/kWh.     

鄂尔多斯TSP和PM_(10)中有机氯农药的分布与来源

于2012年5月在内蒙古鄂尔多斯的东胜、纳林希里、棋盘井和上湾等4个采样点连续采集大气TSP和PM10样品,利用GC-MS分析了其中18种OCPs。结果表明:除了硫丹Ⅱ、硫丹Ⅰ和α-HCH未检出,β-HCH部分检出以外,其余14种OCPs均有100%检出。鄂尔多斯东胜、纳林希里、棋盘井和上湾TSP中∑OCPs浓度依次为2.63、9.85、5.09和6.22ng/m3;在PM10中为2.13、8.74、4.84和6.77ng/m3。∑OCPs中比重超过15%的有ADs、HCs和DDTs。TSP中∑OCPs浓度基本高于PM10中浓度,并且它们存在较好的正相关,相关系数r达到0.8846。污染源分析表明,纳林希里HCHs、CDs和DDTs可能均有外源输入。     

昆明市清水海水源保护区生态补偿机制探讨

就昆明市清水海水源区生态补偿机制进行探讨,以期为生态补偿机制的建立提供借鉴。生态补偿理论结合清水海水源区实际分析。补偿主体是国家、受水区的企业和居民,客体是水资源和生态环境的保护者,以及牺牲发展机会的企业和居民;补偿标准以费用分析法计算,包括水资源保护、水源林建设和管理等方面的投入;补偿方式近期以输血型和造血型补偿结合,远期逐步向生态造血型补偿转变;优先补偿效率高的污染防治措施、退耕还林和测土配方,其次为产业结构调整和水资源管理;补偿时限结合补偿取得的成效、水源区生态产业发展和生态质量状况来确定;补偿资金以政府财政为主、市场为辅。结果表明:应结合清水海的实际,确定生态补偿的主客体、方式、标准和时限,建立生态补偿的保障机制,加强对补偿资金的监管。进一步开展定量化研究,完善清水海水源区生态补偿基础研究,促进生态补偿机制的建立。     

Comparison among filter-based,impactor-based and continuous techniques for measuring atmospheric fine sulfate and nitrate

Filter-based methods for sampling aerosols are subject to great uncertainty if the gas–particle interactions on filter substrates are not properly handled. Sampling artifacts depend on both meteorological conditions and the chemical mix of the atmosphere. Despite numerous of studies on the subject, very few have evaluated filter-based methods in the Asian environments. This paper reports the results of a comparison of the performances of two filter-based samplers, including a Thermo Anderson Chemical Speciation Monitor (RAAS) and a honeycomb denuder filter-pack system, a Micro Orifice Uniform Deposit Impactor (MOUDI) and a real-time ambient ion monitor (AIM, URG9000B) in measuring atmospheric concentrations of PM_2.5 sulfate and nitrate. Field studies were conducted at an urban site in Jinan, Shandong province, during the winter of 2007 and at a rural site near Beijing in the summer of 2008. The AIM was first compared with the honeycomb denuder filter-pack system which was considered to have minimal sampling artifacts. After some modifications made to it, the AIM showed good performance for both sulfate and nitrate measurement at the two sites and was then used to evaluate other instruments. For the un-denuded RAAS, the extent of sampling artifacts for nitrate on quartz filters was negligible, while that on Teflon filters was also minimal at high nitrate concentrations (>10 μgm^?3); however, loss through evaporation was significant (～75%) at low nitrate concentrations under hot summer conditions. The MOUDI using aluminum substrates suffered a significant loss of nitrate (50–70%) under summer conditions due to evaporation. Considering that the aluminum substrates are still being widely used to obtain size-resolved aerosol compositions because of their low cost and accurate mass weighed, caution should be taken about the potential significant under determination of semi-volatile components such as ammonium nitrate.     

钢管石轻混凝土短柱轴压力学性能试验研究

为研究钢管石轻混凝土短柱的轴压力学性能,以天然碎石体积取代率为变化参数,分别设计并制作了5个圆、方钢管石轻混凝土短柱试件,对其进行了轴压静力加载试验,观察了试件受力的全过程和破坏形态,获取了试件的荷载—位移全过程曲线,分析了碎石取代率对试件受力性能的影响规律。结果表明:在轴心受压荷载作用下,钢管石轻混凝土短柱发生了强度破坏;钢管石轻混凝土轴压短柱的实测荷载—位移全曲线变化趋势基本相同,其工作过程可分为弹性阶段、弹塑性阶段和塑性阶段三部分;随着天然碎石取代率的增加,钢管石轻混凝土轴压短柱的极限承载力、峰值位移总体上均逐渐增加。