Spatial distribution of inorganic nitrogen contents of marsh soils in a river floodplain with different flood frequencies from soil-defrozen period

Contents of inorganic nitrogen (NH4(+)-N and NO3(-)-N) in soil profiles were measured in five typical zones ( including permanently flooded floodplain(B), 1-year floodplain (O), 5-year floodplain (F),10-year floodplain (T), and 100-year floodplain (H) )from Huolin River floodplain in Erbaifangzi, Jilin Province of China, in the soil-defrosted period (Mayof 1999). Contour maps and profile maps were constructed to describe the spatial distributions of NH4(+)-N and NO3(-)-N) in order to identify the influences of flood frequencies on them. Results showed that NH4(+)-N generally increased with depth in soil profiles from the five areas, but NH4(+)-N contents in T or H areas significantly differed from those in other areas. For NO3(-)-N, with the exception that there was a significant cumulative peak (6.77 +/- 0.08 mg kg(-1)) at 15-cm depth (10-20 cm) in B area, no significant difference was observed between NO3(-)-N contents in soil profiles from the other four areas. The horizontal distributions of NH4(+)-N and NO3(-)-N in top soils (0-10 cm) were different in the five areas,which were greatly influenced by flood frequencies. The highest content of NH4(+)-N or NO3(-)-N did not appear in B area but in the floodplain with certain flood frequency. For example, NH4(+)-N content (16.81 mg kg-(1)) in 5-year floodplain wetland was highest, and the highest content of NO3(-)-N(1.69 mg kg(-1)) appeared in 1-year floodplain wetland. In addition, NH4(+)-N contents were significantly correlated with soil pH, and NO3(-)-N contents had significant correlation with inorganic carbon, but there were no significant correlations between inorganic nitrogen and other selected soil properties.     

β-环糊精及羧甲基-β-环糊精对取代吲哚化合物的增溶

本文用羧甲基－β－环糊精及β－环糊精对两种取代吲哚化合物２－（４’－甲氧基苯）－吲哚与２－（３‘,４’－二甲基苯）－吲哚进行了增溶实验,结果表明：羧甲基－β－环糊精与二者均形成稳定的１：１的包合物,而β－环糊精与二者形成１：２的包合物。     

批量平衡法研究芳香族酮类化合物在东北黑土中的吸附

本文用批量平衡法研究－系列芳香族酮类化合物在东北黑土中的吸附,采用Ｆｒｅ－ｎｕｎｄｌｉｃｈ吸附等温方程求得土壤吸附常数（ｋｆ）,研究表明：１２种芳香族酮类化合物的吸附等温线有线性和非线性两种形式,对化合物的土壤有机碳吸附常数（ｌｇＫｏｃ）进行定量结构－性质（ＱＳＰＲ）分析,发现芳香族酮类化合物的土壤有机碳吸附常数与正辛醇／水分配系数相关不显著,土壤有机碳吸附常数与分子极化率（ａ）有较好的相关性,这     

厌氧水解—高负荷生物滤池处理城镇污水的中试研究

厌氧水解 -高负荷生物滤池是一种利用附着在塑料模块填料上的微生物系统对城镇污水中的污染物质进行降解处理的绿色环保技术。厌氧水解池和高负荷生物滤池采用的塑料模块填料具有高空隙率、高附着面积、高布水性能和抗堵塞的优异性能 ,并无须回流。当厌氧水解池水力停留时间为 4h ,生物滤池水力负荷为 30m3/ (m2 ·d) ,该系统处理城镇污水的CODcr去除率达 75 % - 85 % ,BOD5去除率达 85 % - 95 % ,SS去除率达 85 % -95 % ,处理后出水的上述各项指标均可满足国家二级生物处理排放标准的要求。     

β-环糊精聚合物微球吸附Pb~(2+)的动力学研究

以β-环糊精(3-CD)为原料、环氧氯丙烷(ECH)为交联剂,制得β-环糊精聚合物(β-CDP)微球。研究了β-CDP微球对Pb~(2+)的吸附特性和动力学。实验结果表明,β-CDP微球对Pb~(2+)的吸附既符合一级动力学方程,也符合二级动力学方程。β-CDP微球对Pb~(2+)的Langmuir吸附等温线的线性拟合方程为ρ_e/Q_m=0.049 5ρ_0+0.030 3,相关系数为0.993 7;β-CDP微球对Pb~(2+)的Freundlich吸附等温线的线性拟合方程为lgQ_e=0.145 4 lgρ_e+0.970 1,相关系数为0.992 9。     

基于区域组团式水热能综合利用的化纤行业节能减排模式

介绍了区域组团式水热能综合利用的模式,区域组团式水热能综合利用以节能、降耗、减污、增效为目标,从大型企业、工业园区或镇市三个层面构建包含有工业企业、商业办公区、居民区、污水处理厂、热电厂及水体在内的多主体的水、热、能综合利用网络,形成以水为物质和能量载体的新的利用模式。以污水厂和热泵为中心的江苏恒力集团有限公司(简称恒力集团)的水热能综合利用网络,可实现集团内的废水零排放,回收的能源占恒力集团能源年消耗量的9.4%,年产生效益约4820万元。组团式水热能综合利用的思路为当前我国各行业的节能减排提供了一种新模式。     

长江八里江江段江豚种群数量、行为及其活动规律与保护

1989－1999年，在长江八里江江段对江豚进行了28次往返观察和8次定点观察。结果表明，近10年八里江江段江豚种群数量遥感量逐年呈明显递减趋势，平均每年以7．3％速率递减；1996年后，枯水季节江豚不再进行江一湖迁移，其活动范围仅限于约20km长的八里江江口上下江段，较1993年以前缩短了约40km。江豚在八里江江段的行为多种多样，通过对江豚种群在八里江江段的集群、摄食、逃避、发情与交配、抚幼、歇息和玩耍行为的描述、比较和分析，认为长江八里江江段是江豚典型的摄食和抚幼场所，同时也是江豚大规模集群的适宜栖居地。提出了加强八里江江段江豚种群常年监测的必要性，并对八里江江段江豚种群的就地保护提出了建议。     

人为失误及其辨识技术的研究

随着机器设备的可靠性不断提高，人的可靠性分析研究日益得到重视。大部分事故是由于人为失误造成的。分析了人为失误与事故发生的关系，讨论了管理失误对系统安全的影响；讨论了人为失误辨识的作用，对人为失误率预测技术、通过失误建模系统、人为失误率评价和优化系统等几种的人为失误辨识技术进行了评述。指出了人为失误及其辨识技术的发展趋势和方向。     

城市污泥/磷尾矿陶粒的烧结条件及性能研究

以城市污泥和磷尾矿为原料,选取4个质量混合比(2:1、1:1、1:2、1:3),在不同烧结条件下(5个温度、5个时间)制备陶粒,对陶粒的堆积密度、吸水率、盐酸可溶率进行测定并对原料和部分陶粒进行XRD物相分析.研究结果显示:随着污泥添加比增大,陶粒堆积密度降低,盐酸可溶率(2:1除外)和吸水率升高.污泥:磷尾矿质量比为...     

Humidity and PM2.5 composition determine atmospheric light extinction in the arid region of northwest China

Atmospheric visibility can directly reflect the air quality. In this study, we measured water-soluble ions (WSIs), organic and element carbon (OC and EC) in PM_2.5 from September 2017 to August 2018 in Urumqi, NW China. The results show that SO₄^2?, NO₃^? and NH₄⁺ were the major WSIs, together accounting for 7.32%–84.12% of PM_2.5 mass. Total carbon (TC=OC+EC) accounted for 12.12% of PM_2.5 mass on average. And OC/EC > 2 indicated the formation of secondary organic carbon (SOC). The levels of SO₄^2?, NO₃^? and NH₄⁺ in low visibility days were much higher than those in high visibility days. Relative humidity (RH) played a key role in affecting visibility. The extinction coefficient (b_ext) that estimated via Koschmieder formula with visibility was the highest in winter (1441.05 ± 739.95 Mm^?1), and the lowest in summer (128.58 ± 58.00 Mm^?1). The b_ext that estimated via IMPROVE formula with PM_2.5 chemical component was mainly contributed by (NH₄)₂SO₄ and NH₄NO₃. The b_ext values calculated by both approaches presented a good correlation with each other (R² = 0.87). Multiple linear regression (MLR) method was further employed to reconstruct the empirical regression model of visibility as a function of PM_2.5 chemical components, NO₂ and RH. The results of source apportionment by Positive Matrix Factorization (PMF) model showed that residential coal combustion and vehicle emissions were the major sources of b_ext.