规模化蛋鸡养殖场栏舍氨排放规律研究

对江西某规模化蛋鸡养殖场栏舍开展每个季节的栏舍氨排放浓度监测,并核算各季节每只蛋鸡的小时栏舍氨排放量和日栏舍氨排放量。结果表明:(1)氨排放浓度和每只蛋鸡的小时栏舍氨排放量具有明显的日变化特征,即白天高、夜间低,主要受温度和相对湿度的综合影响;(2)氨排放浓度和每只蛋鸡的小时栏舍氨排放量的季节变化特征不同,夏季氨排放浓度低但每只蛋鸡的小时栏舍氨排放量大,冬季正好相反,这与该蛋鸡养殖场采用机械通风有关;(3)4个季节每只蛋鸡的日栏舍氨排放量平均为0.372g/(d·只),较国外同为清粪带式结构的蛋鸡栏舍高,建议提高清粪频率。     

沈阳市大气中PM2.5来源解析研究

通过2015年在沈阳市采集PM2.5样品及源类样品,分析样品的质量浓度和化学组成,用化学质量平衡(CMB)模型对该市PM2.5来源进行解析。结果表明:沈阳市大气中PM2.5浓度时空变化特征明显;各主要源类对沈阳市PM2.5的分担率依次为煤烟尘(28.03%)、二次无机离子(22.63%)、机动车尾气尘(17.27%)、城市扬尘(13.28%)、建筑尘(5.94%)、土壤风沙尘(5.82%)、道路尘(3.04%)、生物质燃烧尘(2.74%)和冶金尘(1.25%)。燃煤和机动车的有效控制既能降低本类源的贡献,也能降低二次无机离子,体现了多源类综合治理原则。     

3种材料添加对紫色土吸附四环素的影响

采用批量处理法探究活性硅酸钙（S）、膨润土（B）、硅藻土（D）的添加对紫色土（P）吸附四环素（TC）的影响。结果表明：各供试土样对TC的吸附符合Langmuir模型,最大吸附量qm在564 mmol/kg~5413 mmol/kg之间,且当材料添加质量分数为5%时土样对TC吸附效果最佳;相同材料添加比例下,土样对TC的吸附量均呈现出P-B＞P-S＞P-D＞P;热力学参数表明,TC吸附是一个自发、吸热和熵增的反应,当pH值为5、离子浓度为01 mol/L时吸附量达到最大。     

下蜀土导热系数与电阻率和剪切波速关系模型试验研究

针对导热系数现场难以快速、准确测试的问题,以下蜀土为研究对象,建立了依据电阻率和剪切波速估算导热系数的关系模型。分别采用HC-110热导测试仪、四极法和弯曲元测试系统对20℃、含水率为10%～21%、干密度为1.5～1.8 g/cm3下蜀土的导热系数、电阻率和剪切波速进行了测试,得到了三者与含水率和干密度之间函数关系,建立了导热系数与电阻率和剪切波速的关系模型,经检验,该关系模型拟合度高,为工程实践中利用电阻率和剪切波速快速确定土体导热系数提供了新的方法。     

考虑汇流过程的楼梯疏散模型研究∗

为探究汇流过程对楼梯疏散的影响程度,运用排队论原理,计算楼层平台人流输出率;引入楼梯汇流比率,描述单位时间内楼梯人流通过率与楼层通道人流通过率;以楼梯汇流过程为基础,结合楼层平台人流输出率与汇流比率,将整个楼梯疏散划分为三个阶段,剖析各阶段内行人流相互作用关系,构建楼梯疏散模型,刻画楼梯疏散中人流量动态变化的过程。设置不同楼层通道宽度,计算汇流比率,模拟不同汇流比率下楼梯疏散过程,结果表明:楼梯疏散能力受楼层汇流过程的影响,随汇流比率的增加,楼层平台人流输出率与楼梯的疏散能力均呈现先增后减的趋势,当汇流比率为 0.46 时,即楼层通道宽度为 130 cm 时,楼层平台人流输出率与楼梯疏散能力达到最大。     

微波功率、辐射时间及污泥量对污泥微波干燥效能的综合影响研究

通过正交实验探讨了微波功率、辐射时间及污泥量对污泥微波干燥效能的综合影响研究,实验结果表明:在微波功率为140～580 W,辐射时间为5～20 min,污泥量为200～350 g的实验条件下,微波功率、辐射时间及两者之间的交互作用对污泥微波干燥效能影响高度显著,污泥量影响不显著;并得出微波功率、辐射时间对污泥含水率综合影响的定量正交回归方程。     

苏州太湖湿地芦苇生物量与水深的动态特征研究

随着城市工业化水平和人民生活水平的不断提高,城市淡水湖泊的破坏越来越严重,部分湖泊水质污染严重,湿地面积锐减、功能退化.通过对苏州太湖国家旅游度假区湿地整个生长季的芦苇群落的调查,分析芦苇生物量的季节分配规律及水深与芦苇根冠比、株高和密度的相互关系,为苏州太湖湿地生态系统的保护和恢复提供理论依据.结果表明:(1)芦苇地上生物量从2009年4月至2010年1月呈先增后减的趋势,10月下旬达到最大值((2 219.46± 280.86) g/m2);10月下旬的芦苇根冠比最高,达到了2.4,而4月底的芦苇根冠比最低(1.5);(2)季节性淹水区(简称SFF区)地上生物量明显高于干旱区(简称AF区),淹水区(简称FF区)居中;AF区根冠比稍高于FF区和SFF区;(3)10月下旬芦苇地下0～100 cm深处根系生物量最高,达到了(5 113.41± 313.86) g/m2;地下50～70 cm处根系生物量(质量分数为(28.33±4.15)%)明显高于20～40 cm处根系生物量(质量分数为(19.85±1.59)%),而0～20、80～100 cm处根系生物量质量分数较低,仅分别为(13.05±2.35)%和(15.87±3.52)%;(4)芦苇的根冠比及密度与水深呈反比,芦苇的株高与水深呈正比.     

Potential Economic Benefits of Adapting Agricultural Production Systems to Future Climate Change

Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an historical climate period (1960–2005) and future climate period (2006–2050) are compared when agricultural production systems (APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and A2 CO₂ emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include: (1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2) simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to offset the adverse impacts on NFI of such change.     

Efficacy of forming biofilms by <Emphasis Type="Italic">Pseudomonas migulae</Emphasis> AN-1 toward in situ bioremediation of aniline-contaminated aquifer by groundwater circulation wells

The formation and activity of aniline-degrading biofilms developed by the psychrotrophic Pseudomonas migulae AN-1 were studied for the in situ remediation of contaminated aquifer using in-well bioreactor of groundwater circulating wells (GCWs). Biofilms grown in mineral salt medium with aniline exhibited tolerance to high concentrations of aniline. In aniline degradation rate, AN-1 biofilms exhibited slight differences compared with planktonic cells. The effectiveness and bio-implication of AN-1 biofilms in GCWs were investigated to treat aniline-contaminated aquifer. The results demonstrate that AN-1 biofilms survived the GCWs treatment process with high aniline-degrading efficiency. This system provides a novel environmentally friendly technology for the in situ bioremediation of low-volatile contaminants.