CE-QUAL-W2模型在上海市大型饮用水水库中的应用

通过二维纵向横向平均水动力学和水质模型（CE-QUAL-W2模型）来模拟上海大型饮用水水库的水质状况。模型初步模拟了该水库中不同深度水层的水质状况,使用2011年1月到2011年11月单月（包含一年四季代表性）的数据对模型主要参数进行校正。结果显示,水质状况的模型计算值与实测值比较接近,与实际情况较吻合,AME和RMS值较好,预测该水库的水质是Ⅰ～Ⅱ类。通过本文对该（CE-QUAL-W2模型）的应用得出的结果显示,该模型也适合模拟一些具有湖泊特性的河流,尤其适用于对水体的水质评估。     

漳江调水工程水质目标可达性研究

针对峰头水库和漳江干流,分别建立零维水质模型和一维非稳态水量水质数学模型,并对参数进行率定。对9种不同调水方案实施后漳江流域近期(2015年)和远期(2020年)水质情况进行预测,结果表明:随着调水量和排污量的增加,漳江水质远期差于近期,且取水口越往漳江下游设置,调水对漳江水质的影响越小;总体上调水对漳江水质影响不大,调水后漳江水质达到地表水Ⅲ类水标准;漳江调水工程从对水质影响方面来说是可行的。     

基层环境监察工作的现状及措施

基层环境监察工作是环境保护工作的重要环节。本文针对基层环境监察工作的现状和存在的主要问题进行了简要分析,根据部分地区基层环境监察部门的成功经验,并就如何提高基层环境监察水平提出了一些具体措施和方法,对从事环境监察的人员有着一定的参考价值和借鉴意义。     

冬季黄东海颗粒有机碳的时空分布特征

根据2007年1～2月对黄东海大面调查的资料,分析研究了黄东海颗粒有机碳(POC)的时空分布特征。结果表明,冬季黄东海POC的浓度范围是2.49～1 658.96μg/L,平均浓度为125.88μg/L。在垂直方向上,POC由上而下随着水深的增加浓度逐渐降低,到底层后浓度又升高。在平面分布上,POC整体上呈现西部近岸浓度较高、东部离岸浓度较低的特点;POC的高值区集中在浙江近岸海区,特别是浙江舟山群岛南部近海,POC浓度非常高,这是受陆源输入和沉积物再悬浮的共同作用。在周日变化上,受潮汐作用和海区生物活动的影响,东海陆架中部海域除底层以外,其它各层POC在午后、傍晚、凌晨出现浓度的高峰值,而西南海域,除了底层外,其它各层均表现出全日周期变化。     

青海大柴旦及周边地区尾波衰减特性研究

采用Sato单次散射模型,利用大柴旦台数字地震资料,研究了大柴旦震群序列尾波Qc值在流逝时间窗长60～90 s时间内的变化特征,计算频率从3 Hz至18 Hz,得到Qc值随频率的变化关系：Qc（f）=（72±19.9）f0.93±0.08。计算结果反映出大柴旦地震余震序列的尾波Qc值较低,说明大柴旦震源区属于构造运动较为活跃的地区,这与大柴旦地质结构特征相符。     

Smooth surface fabrication in mask projection based stereolithography

The surface finish is critical for applications such as optics, micro-fluid flow and mechanical assembly, in which optical lenses, fluidic channels and rotating components are all required to be smooth. However, the stair-stepping effect is well known in the layer-based additive manufacturing processes, in which a three-dimensional model is approximated by a set of two-dimensional layers. Consequently the fabricated surfaces have poor surface finishes especially those that are close to the horizontal plane. In this paper, a novel approach for achieving improved surface finish is presented for the mask-image-projection-based stereolithography (MIP-SL) process. Theoretical models and parameter characterization are presented for the developed methods. Accordingly, the process planning and calibration approaches for fabricating smooth up-facing surfaces in the MIP-SL process have been developed. Multiple test cases based on various types of curved surfaces have been performed. A comparison of the build results based on the traditional and the newly developed approaches illustrates the effectiveness of our method.     

基于排队论的城市垃圾箱最佳间距研究

针对城市垃圾箱最佳间距的研究不够精细的现状,本文通过建立排队论模型得到了可供不同城市参考的城市垃圾箱最佳间距参数表。通过对部分城市街道的垃圾箱摆放间距情况进行实地调查,运用层次分析法将影响垃圾箱间距分布的多重因素转化为单因素;建立了基于指数分布的教学模型,利用排队论分析单因素状态下的垃圾箱间距分布,得到了求解城市垃圾箱最佳间距的一般方法。     

内部装修的消防安全隐患及对策

随着改革开放和市场经济的不断发展,人们生活质量的不断提高,对于建筑内部装修和布置要求也越来越高档、豪华、舒适,尤其是一些歌舞厅、KTV包厢、桑拿浴室、网吧等公共娱乐场所以及宾馆、饭店、大型商场等公共聚集场所和不在少数的居民家庭,为了减轻结构自重,方便建筑内空间的合理划分和追求室内装饰时尚、品味,忽视消防安全,在建筑中大量使用易燃、可燃高分子材料,并大量使用合成及塑料制作的家具.……     

Effects of irrigation,fertilization and crop straw management on nitrous oxide and nitric oxide emissions from a wheat–maize rotation field in northern China

One-year winter wheat–summer maize rotation is the most popular double cropping system in north-central China, and this highly productive system is an important source of nitrous oxide (N₂O) and nitric oxide (NO) emissions due to the high fertilizer N and irrigation water inputs. To sustain the high crop production and mitigate the detrimental impacts of N₂O and NO emissions, improved management practices are extensively applied. The aim of this study is therefore to evaluate the effects of an improved management practice of irrigation, fertilization and crop straw on grain yield and N₂O and NO emissions for a wheat–maize rotation field in northern China. Using automated and manual chamber measuring systems, we monitored N₂O and NO fluxes for the conventional (CT, 2007–2008), improved (IT, 2007–2008), straw-amended (WS, 2008–2009), straw-not-amended (NS, 2008–2009), and no N-fertilizer treatments (WS–NN, 2008–2009), respectively, for one rotation-year. The grain yields were determined for CT and IT for three rotation-years (2005–2008) and for WS, NS and WS–NN for one rotation-year (2008–2009). The improved management of irrigation and fertilization reduced the annual N fertilization rate and irrigation amount by 17% and 30%, respectively; increased the maize yield by 7–14%; and significantly decreased the N₂O and NO emissions by 7% (p < 0.05) and 29% (p < 0.01), respectively. The incorporation of wheat straw increased the cumulative N₂O and NO emissions in the following maize season by 58% (p < 0.01) and 13%, respectively, whereas the effects of maize straw application were not remarkable. The N₂O and NO emission factors of applied N were 2.32 ± 2.32% and 0.42 ± 1.69% for wheat straw and 0.67 ± 0.23% and 0.54 ± 0.15% for chemical N-fertilizers, respectively. Compared to conventional management practices using high application rates of irrigation water and chemical N-fertilizer as well as the field burning of crop straw, the improved management strategy presented here has obvious environmentally positive effects on grain yield and mitigation of N₂O and NO emissions.