AAO-MBR工艺污水处理系统中消毒副产物前体物变化规律

为探究DBPs（消毒副产物）前体物在污水处理过程中的变化情况,采用超滤膜和XAD大孔吸附树脂将AAO-MBR工艺沿程出水中DOM（溶解性有机物）进行分离,并利用3D-EEM（三维荧光光谱）对分离前后水样进行表征,同时测定DBPFP（消毒副产物生成势）.结果表明:①沉砂池出水具有较低的C-DBPFP（含碳消毒副产物生成势）;经过AAO和MBR后,由于微生物代谢作用生成的疏水性SMPs（微生物代谢产物）类物质（为主要的C-DBPs前体物质）包含较多不饱和键,导致C-DBPFP增加.②沉砂池出水的N-DBPFP（含氮消毒副产物生成势）较低,但经过AAO后生成的小分子物质（为主要的N-DBPs前体物）导致N-DBPFP增加;经过MBR后由于SRT（污泥停留时间）和污泥浓度的增加造成小分子物质减少,致使N-DBPFP降低.③市政污水经过AAO后,C-DBPs和N-DBPs前体物分别增加了90.9%和7.3%;而MBR具有较高的DOC去除率（74.4%）,去除了56.8%的C-DBPs前体物和78.1%的N-DBPs前体物.研究显示,AAO-MBR工艺对市政污水中C-DBPs和N-DBPs前体物有较好地去除效果.      

KR法铁水脱硫自动控制系统软件的编制及调试

根据KR搅拌式铁水脱硫的工艺流程、设备及操作特点,对铁水脱硫自动控制系统软件进行编制,并对软件调试中出现的问题加以解决,确保系统安全、可靠、高效运行。     

PCrNi3MoVA钢动态再结晶晶粒尺寸的影响因素

此文利用Formastor-Press热模拟试验机研究了Z参数、奥氏体起始晶粒尺寸D_0和应变ε对PCrNi3MoVA铜动态再结晶晶粒尺寸D_(dyn)的影响。通过对试验数据进行分析发现以下规律:①1nD_(dyn)=a+blnZ,②lnD_(dyn)=c+dlnD_0;③lnD_(dyn)=e+flnε 10％≤ε≤40％,其中a、b、c、d、e、f为不同的常数,据此,此文采用线性回归方法获得了上述这些常数的值。     

呼和浩特市大气气态和颗粒物上正构烷烃的研究

采用聚氨基甲酸乙酯和玻璃纤维滤膜采集样品并测定。大气中总正构烷烃的浓度分布、气／固分布比与季节变化、污染源有关。在呼市大气中总正构烷烃（Ｃ１５－Ｃ３３），夏季主要存在气态中（７８％），而冬季主要存在于颗粒物上（８３％）。内蒙古草原大气对照样品中，气态中总正构烷烃在冬夏两季所占百分比都约为５０％。市区冬季大气颗粒物上的总正构烷烃浓度比其它城市结果高出１－２个数量级。     

The role of atmospheric circulation system playing in coupling relationship between spring NPP and precipitation in East Asia area

In many East Asia regions, spring (from March to May) precipitation is an important restricting factor to vegetation growth, and atmospheric circulation system may influence spring precipitation patter. It is helpful to under the response of ecosystem to climate change by studying the influence of atmospheric circulation system on the coupling relationship between spring net primary productivity and precipitation. Driving CASA (Carnegie-Ames-Stanford Approach) NPP (Net Primary Productivity) model, we estimated spring NPP for East Asia area (70 degrees E-1 70 degrees E, 10 degrees N-70 degrees N) from 1982 to 1999, and by the method of singular value decomposition we further analyzed the coupling features of spring NPP with precipitation. The result showed that the response features of NPP to precipitation were mainly embodied within the leading six NPP-precipitation paired-modes. The interpretation rates of the leading six paired-modes to the covariance of NPP-precipitation were 42.91, 23.29, 9.96, 5.60, 5.04 and 3.95%, respectively, and total to 90.75%. The temporal correlation coefficients of the leading six paired-modes were 0.830, 0.889, 0.841, 0.747, 0.912 and 0.923, respectively, and all the correlations were significant at significant level of 0.001. In some high latitude regions, there was no obviously corresponding relationship between NPP and precipitation in the leading two paired-modes, and the reason of it may be that spring temperature was the main restricting factor to NPP. In middle and low latitude regions, the effect of precipitation on NPP was relatively more notable. Nine atmospheric circulation factors in spring affected the patterns of NPP and precipitation greatly, and the regions with interpretation rate over 50% shared 60.41 and 65.58% of the whole study area, respectively.     

闽西北马尾松人工林营养元素的积累与分配格局

通过定位监测与取样分析,研究了41 a生马尾松人工林生态系统中的林木、林下植被、地被物及土壤等各组分营养元素含量、积累及分配特征.对林木的养分含量分析显示,除Ca元素外,针叶的养分含量最高,其次是枝、根、皮,树干的养分含量最低.林下植被层的养分含量比较高,其养分含量大小排列顺序为Ca＞N＞K＞Mg＞P;凋落物中各元素的含量与林木养分含量基本一致;土壤中K含量最高,其次是Mg,而Ca、N、P的含量则比较低.通过对林木生产力的分析表明,马尾松的养分年积累量为110.79 kg·hm-2·a-1,其中叶占34.47%,树干占22.56%,皮、枝和根分别占21.43%、10.91%和10.63%.马尾松林生态系统养分总贮量为187864.77 kg hm-2,其中土壤占98.70%,林木占1.18%,林下植被和凋落物养分元素总贮量较低,仅占总贮量的0.12%.     

微生物降解前后COD差值法快速测定BOD

采用活性污泥曝气法降解前后COD差值的方法,进行了BOD快速检测的研究。条件实验结果表明,其适宜检测条件为:降解时间180 min;污泥量5 mL/100 mL;pH值7.0;温度25℃。模拟废水检测结果表明,该测定方法具有较高的重复性,5次测定的相对偏差小于6.5%,在BOD浓度为0~500 mg/L范围内,微生物降解前后COD差值与BOD5有良好的相关性,其相关系数达到0.98。因此,可以通过测定微生物降解前后COD值,实现快速BOD检测的目的,同时,也可实现COD和BOD一体化检测,这将是今后COD和BOD检测研究的发展方向之一。     

Aluminium in tea plantations: mobility in soils and plants, and the influence of nitrogen fertilization

The levels of extractable aluminum (Al) in soils of tea plantations, Al concentrations in tea leaves and the impact of nitrogen fertilization on these two parameters were investigated. In addition, the properties of soils from tea plantations were compared to those from soils of adjacent non-tea fields to evaluate the effect of land use conversion (from non-tea soils to tea soils). Exchangeable Al (extracted in 1 mol l⁻¹ KCl) ranged from 0.03 to 7.32 cmol_c kg⁻¹ in 94 tea fields and decreased rapidly with increasing soil pH. In comparison with non-tea soils, tea soils had a significantly lower pH and exchangeable Mg²⁺ concentration but higher organic matter contents and exchangeable K⁺ concentration. Contents of extractable Al were not different (P > 0.05) between these two soils. The concentrations of Al in mature tea leaves correlated significantly with exchangeable Al in soil samples taken at a depth of 20–40 cm and with exchangeable Al saturations in soil sampled at␣depths of 0–20 and 20–40 cm. In the pot experiment, nitrogen fertilization significantly increased extractable Al levels but decreased soil pH and the levels of exchangeable base cations. Nevertheless, the levels of Al in mature leaves and young shoots were significantly reduced by the application of large amounts of N fertilizer.     

乙酸钠为碳源时进水COD和总磷对生物除磷的影响

研究了乙酸钠为碳源时,乙酸盐和总磷浓度对循序间歇式生物除磷工艺运行效果的影响,以及含高浓度乙酸盐废水不能有效除磷的原因结果表明:COD<600mg·L^-1时,随着COD/TP值的增大,总磷去除率提高,COD/TP<50时,磷的去除率提高显著,但当COD/TP>50时,磷的去除变化不大;进水乙酸盐浓度过高(COD>600mg·L^-1)使除磷效率逐渐下降,COD>1000 mg·L^-1会使生物除磷系统完全崩溃;研究发现除磷效率的下降是由于过多的乙酸盐从厌氧段进入了好氧段,引起丝状菌的增殖、污泥膨胀,导致聚磷菌被洗出.