Soil resource availability impacts microbial response to organic carbon and inorganic nitrogen inputs

Impacts of newly added organic carbon （C） and inorganic nitrogen （N） on the microbial utilization of soil organic matter are important in determining the future C balance of terrestrial ecosystems. We examined microbial responses to cellulose and ammonium nitrate additions in three soils with very different C and N availability. These soils included an organic soil（ 14.2% total organic C, with extremely high extractable N and low labile C）, a forest soi1（4.7% total organic C, with high labile C and extremely low extractable N）, and a grassland soil（1.6% total organic C, with low extractable N and labile C）. While cellulose addition alone significantly enhanced microbial respiration and biomass C and N in the organic and grassland soils, it accelerated only the microbial respiration in the highly-N limited forest soil. These results indicated that when N was not limited, C addition enhanced soil respiration by stimulating both microbial growth and their metabolic activity, New C inputs lead to elevated C release in all three soils, and the magnitude of the enhancement was higher in the organic and grassland soils than the forest soil. The addition of cellulose plus N to the forest and grassland soils initially increased the microbial biomass and respiration rates, but decreased the rates as time progressed. Compared to cellulose addition alone, cellulose plus N additions increased the total C-released in the grassland soil, but not in the forest soil. The enhancement of total C- released induced by C and N addition was less than 50% of the added-C in the forest soil after 96 d of incubation, in contrast to 87.5% and 89.0% in the organic and grassland soils. These results indicate that indigenous soil C and N availability substantially impacts the allocation of organic C for microbial biomass growth and/or respiration, potentially regulating the turnover rates of the new organic C inputs.     

水中氟化物的离子选择电极测定法的改进

1 前言氟离子选择性电极法,是测定水中氟化物的主要方法之一。该法选择性好,不受色度、浊度影响,抗阳离子干扰能力强,操作简便,适用范围宽,易于实现水质的连续自动测定。因此,该法得到了广泛应用。我国《地面水环境质量标准》选用了氟离子选择电极一次标准加入法。在测定时.需加入总离子强度调节缓冲溶液(TISAB),使溶液的pH在5—5.5之间,以防止低pH值时生成HF缔合物;高pH时,高浓度OH~-干扰测定。     

几种常用无机混凝剂处理印染废水试验及评述

通过常用无机混凝剂ＰＦＳ、ＰＡＣ、ＦｅＳＯ４．７Ｈ２Ｏ及Ａｌ２（ＳＯ４）３．１８Ｈ２Ｏ处理印染废水试验，确定各自的最佳混凝处理条件。在最佳条件下，４种混凝剂对印染废水都有一定的处理效果。经成本等指标比较后，推荐ＰＦＳ为印染废水处理的适宜混凝剂。     

从无机氮形态及时空分布研究河流污染和自净程度

以ＮＨ３－Ｎ／ΣＮ，ＮＯ３－Ｎ／ΣＮ表示河流的自净程度，并从正常时序和经验频率两方面研究河流污染，自净程度的时空分布，研究结果在水污染控制，水资源规划等环境管理，决策领域具有现实意义。     

混凝剂在污水处理中的现状与发展

介绍了无机絮凝剂、有机絮凝剂及微生物絮凝剂在污水处理中的研究和应用情况,并分析研究发展趋势.     

用酞菁绿废水制备聚合氯化铝絮凝剂的方法

该专利提供了一种用酞菁绿废水制备聚合氯化铝絮凝剂的方法。将335型弱碱性阴离子交换树脂放入吸附柱中，然后用稀盐酸流经吸附柱，再用水或去离子水清洗该树脂柱，然后用稀碱液处理该树脂吸附柱，最后用水或去离子水清洗该吸附柱直至出水呈弱碱性；调节酞菁绿废水的pH，使其在常温到50℃之间，通过上述预处理转型后的335型弱碱性阴离子交换树脂吸附柱，再经过另外一个离子交换树脂吸附柱，即可得到铜离子浓度达到《污水综合排放标准GB8978-1996》中二级标准的酞菁绿废水。将经上述树脂处理的酞菁绿废水浓缩，在搅拌加热的条件下，同时加人碱化剂进行反应，调节废水呈弱酸性，持续搅拌并进行加热反应，即得到该发明的液体产品或固体成品，335型弱碱性阴离子交换树脂还可脱附再生。     

直接电位法测量误差分析

简要介绍了直接电位法的特点，分析了离子选择性电极在测量中的误差来源及操作中应注意的事项。     

催化剂生产废水铵离子选择交换处理工艺

用铵离子选择交换工艺对催化剂生产过程排出的含氨氮废水进行处理。考察了再生液中NH3－N浓度、进水NH3－N浓度、进水悬浮物浓度、进水pH、再生液用量等因素对处理效果的影响；探讨了铵离子选择交换床液体空速与出水NH3－N浓度的关系、铵离子交换床总交换容量与进水NH3－N负荷之比与出水NH3－N浓度的关系。     

磷肥工业含氟废气利用的清洁生产新方法

本文通过对磷肥工业含氟废气利用的现有技术状况的分析，提出一种含氟废气清洁生产的新方法。