壳聚糖-丙烯酰胺-二甲基二烯丙基氯化铵三元接枝共聚物的合成及应用

在N2保护下,以硝硬驱铈铵为引发剂,将壳聚糖（CTS）、丙烯酰胺（AM）及二甲基二烯丙基氯化铵（DMDAAC）接枝共聚得到CTS-AM-DMDAAC三元接枝共聚物,考察了反应条件对接枝共聚反应的影响。实验结果表明,在反应温度50℃、反应时间5-6h,m（CTS）：m（AM）：m（DMAAAC）=1：6：0.67、c（Ce^4＋）=0.8mmol/L的最佳反应条件下,接枝共聚反应的接枝率和接枝效率分别为64%和10.5%。用傅里叶变换红外光谱仪对CTS-AM-DMDAAC进行了表征。絮凝实验结果表明：CTS-AM-DMDAAC对高岭土水样具有较强的絮凝能力,可在很宽的pH范围内使用。用CTS-AM-DMDAAC处理COD为165.5mg/L的啤酒生产废水,COD去除率达90.1%.     

耐低温菌JH-9降解苯胺的动力学研究

研究耐低温菌JH-9在低温(10 ℃)条件下对不同初始ρ(苯胺)的生物降解情况,并采用反应动力学方程(Monod方程和Haldane方程)拟合其降解过程. 结果表明,菌株JH-9在低温下可降解苯胺,当菌体初始质量浓度一定时,苯胺降解率及平均降解速率主要与初始ρ(苯胺)有关. 初始ρ(苯胺)较低时(<550　mg/L),其在120 h内可完全降解,且平均降解速率随着初始ρ(苯胺)的增加而升高,菌体降解过程中没有出现苯胺毒性抑制作用,遵循Monod方程;当初始ρ(苯胺)较高时(>550　mg/L),苯胺降解率及降解速率均有所下降,由于初始ρ(苯胺)过高对菌体产生了抑制作用,其降解过程以基质抑制型的Haldane方程为主.      

渗滤液回灌对填埋垃圾含水率的影响研究

文章通过模拟实验研究了不同的渗滤液回灌频率、回灌量和回灌速率对压实密度不同的垃圾的含水率的影响。研究表明,由于通道流的存在和影响,渗滤液的产生时间提前于填埋垃圾达到其有效贮水率的时间;渗滤液回灌频率越高、回灌量越大、回灌速率越慢、垃圾体温度越低、垃圾压实密度越高,则填埋垃圾的有效贮水率越大、含水率越高。在实施渗滤液回灌操作时,须综合考虑滤液回灌频率、回灌量、回灌速率、垃圾温度和垃圾压实密度等影响因素。     

青藏高原地区准好氧填埋单元试验研究

为研究准好氧填埋技术在海拔高、空气稀薄、气温低、昼夜温差大、蒸发强、降雨少的青藏高原地区的适用性,在青藏高原不冻泉地区开展了为期14个月的准好氧填埋单元试验研究.试验结果表明,准好氧填埋单元的渗滤液COD浓度由3307 mg/L降低到403 mg/L,氨氮由135.4 mg/L降低到0.04 mg/L,渗滤液量大幅减少.研究为青藏高原地区提供了一种垃圾处理方式.     

混凝-IBAC深度处理焦化废水的试验研究

以哈尔滨某气化厂焦化废水为目标,探讨混凝-固定化生物活性炭(IBAC)工艺对哈尔滨气化厂焦化废水进行深度处理的净化效能及其可行性.采用筛选、驯化的脱酚菌,对活性炭(GAC)进行固定,使之形成固定化生物活性炭.当该工艺进水COD＜800 mg/L时,出水COD在100 mg/L以下,平均去除率在80%左右;当进水总酚在200 mg/L以下时,出水的总酚含量基本在20 mg/L以下;当进水氨氮浓度在75 mg/L以下时,出水氨氮浓度在25 mg/L以下.焦化废水中各污染物指标经混凝-IBAC工艺深度处理后可达污水综合排放标准(GB 8978-1996)的二级标准.     

烟道气生物脱硫厌氧段影响因素的研究

采用UASB对烟道气生物脱硫厌氧段中的主要影响因素如水力停留时间、进水浓度和温度进行实验研究。分别从亚硫酸根去除效果和硫化物生成情况两方面考查对反应器运行效果的影响。结果表明,水力停留时间为36h时,SRB对SO32-的还原效果良好;进水SO32-浓度范围在500～800mg/L时,SO32-还原率在88%左右;在实验考察的温度范围内,反应温度为33℃时SO32-还原速率和硫化物产生量最大。     

烟颗粒对太赫兹波衰减特性的影响研究

太赫兹成像系统相对于普通红外线成像系统而言,其受温度和烟雾密度的影响较小,将其引入火场环境侦测中能较好地解决火场环境能见度低的问题.但太赫兹波在火场烟气环境中传播时,会受到烟颗粒的吸收和散射作用影响,造成其传播特性发生变化,因此有必要开展烟颗粒对太赫兹波衰减特性的影响研究.采用离散偶极子近似法进行模拟运算,结合烟颗粒分...     

Estimating plant-available nitrogen release from manures, composts, and specialty products

Recent adoption of national rules for organic crop production have stimulated greater interest in meeting crop N needs using manures, composts, and other organic materials. This study was designed to provide data to support Extension recommendations for organic amendments. Specifically, our objectives were to (i) measure decomposition and N released from fresh and composted amendments and (ii) evaluate the performance of the model DECOMPOSITION, a relatively simple N mineralization/immobilization model, as a predictor of N availability. Amendment samples were aerobically incubated in moist soil in the laboratory at 22 degrees C for 70 d to determine decomposition and plant-available nitrogen (PAN) (n = 44), and they were applied preplant to a sweet corn crop to determine PAN via fertilizer N equivalency (n = 37). Well-composted materials (n = 14) had a single decomposition rate, averaging 0.003 d(-1). For uncomposted materials, decomposition was rapid (>0.01 d(-1)) for the first 10 to 30 d. The laboratory incubation and the full-season PAN determination in the field gave similar estimates of PAN across amendments. The linear regression equation for lab PAN vs. field PAN had a slope not different from one and a y-intercept not different than zero. Much of the PAN released from amendments was recovered in the first 30 d. Field and laboratory measurements of PAN were strongly related to PAN estimated by DECOMPOSITION (r(2) > 0.7). Modeled PAN values were typically higher than observed PAN, particularly for amendments exhibiting high initial NH(4)-N concentrations or rapid decomposition. Based on our findings, we recommend that guidance publications for manure and compost utilization include short-term (28-d) decomposition and PAN estimates that can be useful to both modelers and growers.     

Policy Windows, Policy Change, and Organizational Learning: Watersheds in the Evolution of Watershed Management

Employing in-depth, elite interviews, this empirical research contributes to understanding the dynamics among policy windows, policy change, and organizational learning. First, although much of the research on agenda setting—how issues attract enough attention that action is taken to address them—has been conducted at the national scale, this work explores the subnational, regional scale. With decentralization, regional-scale environmental decision-making has become increasingly important. Second, this research highlights the role of policy windows and instances of related organizational learning identified by natural resources managers. Having practitioners identify focusing events contrasts with the more typical approach of the researcher identifying a particular focusing event or events to investigate. A focusing event is a sudden, exceptional experience that, because of how it leads to harm or exposes the prospect for great devastation, is perceived as the impetus for policy change.     

基于第二次全国污染源普查质量保证的思考及体系建设初探

通过对清查数据的结果分析,确定第二次全国污染源入户普查的对象,基于企业填报、现场入户、资料收集审核、数据核查等具体工作的实施与开展,思考和归总普查工作中影响数据质量的现实问题和难点,初步构建污染源普查质量保证体系,以期为全国污染源普查数据质量保证提供有益参考。