DMPP对稻田田面水氮素转化及流失潜能的影响

采用杭嘉湖地区典型的小粉土和青紫泥土壤,进行水稻盆栽试验,研究新型硝化抑制剂3,4-二甲基吡唑磷酸盐(DMPP)对稻田田面水氮素转化及径流流失潜能的影响.结果表明,小粉土和青紫泥土壤稻田应用添加DMPP抑制剂的尿素,与常规尿素处理相比,田面水中铵态氮的浓度增加24.8%和16.7%,硝态氮浓度降低47.7%和70.9%,亚硝态氮浓度降低90.6%和88.9%,总无机氮浓度下降13.5%与23.1%,能显著减轻农田氮素流失对水环境存在的污染;DMPP可使田面水的电导率下降,降低盐基离子随农田排水或暴雨径流所导致的流失风险,有助于保护河流水体等地表水环境.     

大鹏湾环境容量研究Ⅱ:环境容量规划

采用基于响应场的线性规划方法,考虑非点源与湾外污染物输入形成的本底值,结合深圳沿岸排污口的分布计算了大鹏湾的环境容量,并给出了总量分配方案.结果表明,大鹏湾物理自净能力差,但水体容量大,具有较大的稀释容量,加上污染物的生化降解,大鹏湾具有较大的环境容量.BOD5、总氮、总磷的最大允许排放总量分别为79.0,11.418,0.86t/d,BOD5、总氮、总磷的剩余环境容量分别为61.34,9.318,0.43t/d.     

Effect of dietary factors and environmental chemicals on intestinal drug metabolizing enzymes

The liver is the major site of metabolism of foreign chemicals, but contribution from intestinal biotransformation can influence the overall disposition of chemicals. The intestinal drug‐metabolizing enzymes are located in the endoplasmic reticulum and they possess biochemical properties similar to those of the hepatic system. In general, the rate of in vitro metabolism of drug substrates in intestines is lower than in the liver. There seem to be differences in regulation and induction of hepatic and intestinal drug‐metabolizing enzymes. The in vitro intestinal metabolism of foreign chemicals is affected by several factors including the nutritional status of the animal. Dietary components such as vitamins, lipids and vegetables can modify the activities of intestinal drug‐metabolizing enzymes. Phenobarbital or 3‐methyl‐cholanthrene (3‐MC) pre‐treatment induces the hepatic metabolism of a wide variety of drug substrates in a number of species, while the stimulation of intestinal enzymes is both substrate and species specific. Rabbit intestinal drug‐metabolizing enzymes seem to be resistant to induction by foreign chemicals.     

红壤丘陵区冬闲稻田CH4和N2O排放通量的研究

CH4和N2O是与全球气候变化密切相关的2种主要温室气体,其排放规律以及减排措施已成为当前研究的热点。休闲期抛荒稻田普遍存在于我国西南和南方地区,而对于其CH4和N2O排放规律的研究还比较少。本实验选取江西红壤丘陵区进行观测,于稻田休闲期采用静态箱-气相色谱法进行原位观测,旨在探讨休闲期CH4和N2O的排放规律,可为制定减排措施提供一定的依据。研究结果表明：红壤丘陵区冬闲稻田CH4和N2O平均排放通量（以CH4和N2O-N计）分别为0.03mg.m-2.h-1和3.27μg.m-2.h-1。冬闲期CH4和N2O平均排放通量与土温、降雨量无明显线性关系（P〉0.05）。冬闲稻田排放CH4和N2O的综合温室效应（以CO2-eq计）为7.58 g.m-2,其中,CH4和N2O产生的温室效应（以CO2-eq计）分别为2.33和5.25 g.m-2。N2O排放量是冬闲稻田温室气体观测中不可忽视的部分。     

工频电磁场对公众健康及风险感受影响调查

为调查工频电磁场对附近居民健康及风险感受的影响,对16条已投运110~500kV输电线两侧居民(n=615)开展问卷调查,根据输电线运行参数计算工频电磁场相对曝露强度,分析了工频电磁场对距线路中心50m内、外受调查者产生的健康影响差异,以及不同工频电磁场曝露强度、电压等级、塔型附近受调查者风险感受和负面情绪的均值差异,并通过多元线性逐步回归分析分别建立了工频电磁场公众风险感受、负面情绪与影响因素之间的最优回归模型.结果表明,工频电磁场对50m内和50m外受调查者产生健康影响的相对风险值为0.87;在本次调查的工频电磁场范围内(E<0.35kV/m,B<0.80 μT),公众风险感受和负面情绪受工频电磁场曝露强度影响很小,受输电线架线塔外观大小、塔型、既有身体状况等因素影响显著.     

RESEARCH: Managing Mountainous Degraded Landscapes After Farmland Abandonment in the Central Spanish Pyrenees

Genista scorpius. Under a dense shrub cover both runoff and sediment yield are strongly controlled. As the shrub cover becomes open, sediment yield and runoff increase greatly. A dense herbaceous cover yields high runoff coefficients but moderate soil losses. From the results obtained, the possibility of abandoned field reclamation by means of selective clearing of scrub is discussed.     

OPTIMUM USE OF PADDY FIELDS FOR FLOOD MITIGATION1

In Taiwan, the continuously increasing levels of rice imports are likely to result in surplus paddy fields. Hence, the surplus paddy fields may be developed into wetlands to increase ground water recharge, provide appropriate environments for wildlife, and most importantly, store flood water. This study developed a hydrological model incorporating the distributed rainfall‐runoff model based on the kinematics wave approach and the distributed tank model for simulation, respectively, in mountainous and flat areas. The hydrological model was found to simulate the rainfall‐runoff behavior well in the study area. Furthermore, a decision method based on the genetic algorithm concepts was proposed to give policy makers the optimal location and area size of paddy fields to construct wetlands for flood mitigation.     

氧化沟流场的计算流体力学数值模型研究

该研究发展了氧化沟计算流体力学模型。采用三维标准k-ε湍流计算流体力学模型对全尺度氧化沟进行了数值模拟和试验验证,并用动量源项方法描述倒伞曝气机对氧化沟中流体的驱动作用,试验结果和模拟计算间良好的一致性证明了模型的合理性。模拟和试验均发现大量低流速区域的存在,尤其是表面曝气机下部靠近沟底的区域,有必要改善氧化沟的水力学性能。同时,对网格独立性进行了验证,比较了不同湍流模型的计算结果。     

超声Fenton法处理毒死蜱中间体废水的工艺优化

针对毒死蜱中间体生产的化工废水有机物浓度高、生物抑制性强的特点,以实际生产废水为研究对象,基于响应曲面法,进行了超声/Fenton法降解有机物效能研究与运行参数的优化.结果表明:1通过单因素试验确定响应曲面设计的自变量中心点为H2O2投加量0.5 mol/L、Fe2+投加量0.93 g/L、反应时间90 min.2采用Box-Behnken试验设计,建立了以H2O2及Fe2+投加量、反应时间为自变量的回归模型,经方差分析,模型显著(P0.000 1);对有机物去除率影响最大的因素为Fe2+投加量,其与反应时间的交互作用显著.3最优工况为H2O2投加量0.7 mol/L、Fe2+投加量1.36 g/L、反应时间96 min,该条件下模型预测CODCr去除率为96.63%,试验值与模型预测值的相对误差为1.36%,出水水质指标远低于GB 8978—1996《污水综合排放标准》三级标准,ρ(BOD5)/ρ(CODCr)从0.09升至0.22,CODCr单位去除负荷的H2O2及Fe2+用量相对较低,分别为0.14 mmol/mg和0.28 mg/mg.研究显示,采用超声/Fenton法处理高浓度难降解有机废水可有效提高CODCr去除率及其可生化性.     

绿色技术推广：经验借鉴、策略梳理及匹配分析

绿色技术推广是促进绿色科技成果转化,推动社会经济发展绿色转型的重要支撑。本文将绿色技术依据其应对的生态环境问题划分为清洁、循环、低碳3类技术,并挑选了10类关键技术领域作为研究对象。基于对美国、日本、欧盟等发达国家和地区绿色技术推广代表性领域的回顾分析,从政府、企业、中介组织、金融机构、科研院所等推广主体出发梳理出10类绿色技术推广的共性策略,并讨论了当前绿色技术推广的主要障碍。根据各类绿色技术的发展阶段和市场应用情况,就清洁技术的大气污染防治、污水处理、土壤修复和生态养殖技术,循环技术的资源循环利用和垃圾资源化处理技术,低碳技术的工业节能、新能源发电、新能源汽车和绿色建筑技术,分别提出了未来进行技术推广可优先采用的推广策略和特色化举措。