我国东部河流沉积物中的多氯联苯

较全面地研究了我国东部自北向南自然条件和社会经济水平各异的１１条主要河流域市区段沉积物样品中多氯联苯的含量，对１４个同系物与混杂于其中的ＤＤＥ进行了测定，以了解我国主要河流城市区段沉积物ＰＣＢＳ的当前污染水平。测试结果表明，９０年代初我国河流沉积物ＰＣＢＳ的一般水平在１０．５－２５．５ｎｇ／ｇ之间，其中含量最多的同系物是２，２’，５．５ＴｅＣＢ，２，２‘，４，５，５’－ＰｅｎｔａＣＢ，２，２‘，３     

Logistic Regression在我国河流水系氮污染研究中的应用

对四川省岷江、沱江及嘉陵江流域和江西省的赣江流域及鄱阳湖地区共170多个水文站的数据进行了相关分析和多元回归分析。结果表明，河流水中硝态氮浓度与年降雨量、人口密度、氮肥施用量、牲畜饲养量、农作物及粮食作物种植面积等因素有较好的相关性。以以上数据资料为基础，将河流水NO3^--N的浓度划分为背景浓度（＜0．7mg/L)、受人类活动的显著影响的NO3^--N浓度（＞3．0mg/L)以及中间类（0．7－3．0mg/L)进行Logistic Regression分析，两个Logistic模型的准确度分别达82．46％和89．19％。运用Logistic模型对整个长江流域河流水中NO3^--N浓度进行估计，结果与实测值基本相符合。     

Management Model of Resources Equilibrium Distribution among Overlapping-Generations

The overlapping generation models the western scholars have designed from various perspectives to address different kinds of issues do not reflect Chinese emerging political and economic problems, and cannot be entirely and blindly applied to Chinese practical situation. In this paper the authors endeavor to incorporate some western scholars' research results into their own research findings to present overlapping generations model theory in a new perspective through establishing an overlapping generations theory on population including articulation of concepts and theorems of biological generation, economic generation and social generation and the overlapping periods in biological generation and two overlapping periods in economic generation among three generations. This management model with equilibrium distribution of resource wealth includes overlapping generations length model (6), equilibrium transfer model (θ) and a complete model on equilibrium distribution among generations (δ-θ). The model p     

温度对蚯蚓处理城镇污泥稳定化过程的影响

在蚯蚓堆肥过程中,温度会对微生物和蚯蚓活性产生影响,进而影响堆肥效率.将城镇脱水污泥制成5 mm的颗粒,通过比较3个温度条件下(15、20、25℃)赤子爱胜蚓(Eisenia foetida)处理城镇污泥过程中理化、生化指标的变化,研究温度对蚯蚓堆肥稳定化过程的影响.结果显示,在整个稳定化过程中,随温度升高,有机质(OM)、微生物量碳(MBC)降低,电导率(EC)、NH_4~+-N、NO_3~--N升高,而脱氢酶活性(DHA)随温度变化不具有明显规律性.主成分分析(PCA)结果表明,蚯蚓堆肥稳定化过程依次经历以有机质生物降解、氨化和硝化为特征的3个阶段.以蚯蚓适宜生长温度控制蚯蚓堆肥,将更有利于蚯蚓与微生物协同作用的高效发挥.温度能改变蚯蚓堆肥的稳定化效率,但并不改变稳定化路径.     

ABR反应器预处理综合印染废水研究

采用ABR反应器预处理难降解印染废水中试研究。结果表明,ABR反应器最佳水力停留时间（HRT）为24 h,ABR反应器稳定运行4个月,当进水COD平均值为769.4 mg/L（最高1 060 mg/L,最低590.6 mg/L）,色度平均值为351倍时,出水COD和色度分别为424.2 mg/L和83倍,去除率分别为44.5%和76.1%。印染废水B/C由0.27提高到0.42,废水可生化性明显改善。     

CuMnO_x/γ-Al_2O_3及稀土助剂对VOCs催化燃烧性能的影响

利用浸渍法制备了Cu-Mn复合氧化物催化剂和加入不同稀土含量的Cu-Mn复合氧化物催化剂,通过实验优选出加入稀土催化剂中稀土含量的最优配比,以气相色谱为检测手段,考察了加人稀土和不加稀土催化剂的催化燃烧性能,结果表明,加入稀土的催化剂T_(99)(催化处理效率达到99%时的温度)比不加稀土的催化剂降低30～40℃,具有更好的低温活性,且对多种VOCs均能降低反应温度。     

CuMnOx／γ-Al2O3及稀土助剂对VOCs催化燃烧性能的影响

利用浸渍法制备了Cu—Mn复合氧化物催化剂和加入不同稀土含量的Cu—Mn复合氧化物催化剂,通过实验优选出加入稀土催化剂中稀土含量的最优配比,以气相色谱为检测手段,考察了加入稀土和不加稀土催化剂的催化燃烧性能,结果表明,加入稀土的催化剂T99（催化处理效率达到99％时的温度）比不加稀土的催化剂降低30～40℃,具有更好的低温活性,且对多种VOCs均能降低反应温度。     

影响非甲烷总烃监测结果准确性的因素研究及控制

结合非甲烷总烃监测工作实际情况,对样品采集、保存与运输、分析测试与数据处理、采样容器清洗与保存等过程详细研究后发现,采样容器从样品中吸附吸收的难挥发性与高化学活性组分和其自身的本底干扰对监测结果准确性的影响最严重,且其中残留的污染物使用传统方法难以消除。为此,通过改进采样容器清洗方法、完善相关质控措施和制定采样容器合格清洗与分类管理的判断依据,以降低各影响因素对非甲烷总烃监测结果准确性的影响。     

Challenge of biodiesel production from sewage sludge catalyzed by KOH,KOH/activated carbon,and KOH/CaO

The considerable compounds content, abundance, and low costs involved has led to the proposal to use sewage sludge as raw material for biodiesel production. The transesterification reaction is catalyzed using an acid catalyst instead of base catalysts because of the high free fatty acid concentration. However, the use of a base catalyst, particularly a solid base catalyst, has certain advantages, including faster reaction speed and easier separation. In this study, we utilize in situ transesterification by base catalyst (KOH, KOH/activated carbon (AC) and KOH/CaO) with sewage sludge as raw material. Many conditions have been tested to increase biodiesel yield through single-factor tests, including mass fraction and catalyst dosage. Preliminary experiments have optimized reaction time and temperature. However, the three catalysts did not work better than H₂SO₄, which had a maximum yield of 4.6% (dry sewage sludge base) considering the purity by KOH, KOH/CaO, and KOH/AC. The features of the catalyst were analyzed using XRD, BETand SEM. As to BETof KOH/AC and the good spiculate formation of KOH crystal appears to be essential to its function. As for KOH/CaO, the formation of K₂O and absorption points is likely essential.

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