An integrated assessment method of urban drainage system: A case study in Shenzhen City, China

In recent years, the urban drainage system in China is facing the dual pressure of renovation and construction. This requires that the integrated assessment for the planning and operation of the urban drainage system is obligatory. To evaluate the urban drainage system, an integrated assessment methodology based on the analytic hierarchy process (AHP), integrated simulation, and fuzzy assessment is established. This method is a multi-criteria decision adding app roach to the assessment of the urban drainage system comprehensively. Through the integration of the Storm Water Management Model (SWMM), a simple wastewater treatment plant model, and a surface water quality model, an integrated modelling system for the urban drainage system is developed and applied as a key tool for assessment. Using the established method, a case study in Shenzhen City has been implemented to evaluate and compare two urban drainage system reno vation plans, the distributed plan and the centralized plan. Because of the particularity of this case study, the established method is not applied entirely. Considering the water environ mental impact, ecological impact, technological feasibility, and economic cost, the integrated performance of the distri buted plan is better. As shown in this case study, the proposed method is found to be both effective and practical.     

"珠三角"地区城市化对地下水水质影响案例研究

以珠海市东部沿海地区为例,探讨城市化地区地下水化学特征及污染状况的关系.结果表明土地利用类型与地下水水质变化密切相关.香洲区地下水化学组分差异较大,电导率范围为49.4~971 μS/cm.大部分地下水呈弱酸性,林地及果园用地地下水电导率较低,水化学类型多属于Na-HCO3型;老城区及新住宅区地下水类型多属于Ca-Mg-HCO3类型,电导率较高,受NO3-及Cl-污染较为严重.新住宅区地下水NO3-污染状况较老城区更为严重可能与旧村改造及市政排水设施不完善有关.除少数采样点外,地下水化学类型受季节变化影响不大.人为污染与自然风化过程是影响地下水化学类型的重要因素.     

云南粳稻核心种质杂种后代孕穗期耐冷性研究

以236份云南地方粳稻核心种质和云南主栽梗稻Oryza satica品种合系35配制的杂种F5、BC1F4、BC2F3和BC3F2为材料,在昆明自然低温平均17.8℃(冷害)条件下,对亲本及其后代进行孕穗期耐冷性研究.结果表明:①亲本耐冷性状间的相关性明显高于其杂种后代,不同世代间总体趋势为随着回交世代增加其性状间相关性减弱.在亲本及其杂种后代间耐冷指标性状穗颈长、穗下节长、每穗实粒数、每穗秕粒数与结实率均呈较高的(≥0.370)极显著(n=236,R0.01=0.181)相关.②株高、穗颈长、穗下节长等耐冷性状在亲本强弱耐冷系统群间的差异明显,表现为亲本耐冷性强的材料秆和穗较长、穗粒数较多,同一性状变异程度减小.但随着回交代数的增加,这些性状的平均值逐渐趋同于轮回亲本,差异减小.③穗颈长、穗下节长、每穗实粒数、每穗秕粒数与结实率在5个稻作区间的变化规律呈现一致性,亲本和F5的差异较大,而BC2F4、BC2F3和BC3F2的差异较小,且趋同于轮回亲本.通过连续回交,在BC3F1即可获得耐冷性状表现良好的材料.     

火电站污水处理厂最佳投药量优化试验研究

火电厂污水水质和水量变化较大,絮凝剂和助凝剂投药量准确与否决定去除效率和运行成本,本研究针对火电厂实际运行情况,通过静态和动态实验,比较去除效率。根据水质和水量的变化,找到最佳投药量,为污水处理厂的最佳运行提供了参考依据。     

白腐菌应用于堆肥处理含木质素废物的研究

白腐菌对木质素具有较强的降解能力。通过在含大量木质素的模拟垃圾堆肥中采取添加白腐菌菌剂与不添加该菌剂2组实验对比,在相同堆肥处理条件下,接种菌剂的堆肥中木质素总量由274988mg降至15438mg,降解率达4386%,远高于未接种菌剂的堆肥中木质素的降解率,表明白腐菌可有效用于含木质素废弃物的堆肥处理,并有望于加速堆肥腐熟,提高堆肥效率。     

双氰胺-甲醛聚合物-聚合氯化铝复合絮凝剂的合成及应用

以双氰胺、甲醛、氯化铝为主要原料,加入添加剂合成了双氰胺-甲醛聚合物（DF）-聚合氯化铝（PAC）复合絮凝剂。采用模拟印染废水考察了各种因素对DF—PAC复合絮凝剂混凝脱色性能的影响。实验结果表明,在双氰胺、甲醛、氯化铝、添加剂加入量分别为29．1,57．8,4．8,12．5g,反应温度（70±1）℃、反应时间2．5h的条件下制得的DF—PAC复合絮凝剂的絮凝脱色性能良好,COD去除率不小于90％,色度去除率不小于99％。与PAC和DF絮凝剂相比,DF—PAC复合絮凝剂对实际印染废水的絮凝脱色效果更好。     

铁屑还原及微波铁屑诱导氧化降解偶氮染料历程的研究

研究了铁屑内电解还原及微波诱导氧化降解偶氮染料的反应历程,采用胶束毛细管电泳法对跟踪了2种不同降解方法下的中间产物变化.实验结果表明,染料的偶氮键(-N=N-)易被铁屑内电解还原,反应过程中有中间产物苯胺生成.微波诱导铁屑氧化偶氮染料的反应过程中未检测到其他芳环类化合物生成,在微波辐照2 min时脱色率已达90%以上,TOC去除率也高达78%,矿化较为彻底;在微波辐照铁屑诱导氧化降解污染物的同时,也使铁屑自身得以活化再生,提高了铁屑的内电解能力.     

模拟酶蛋白结合物替代HEMIN测定大气过氧化物

在选择最佳测定条件的基础上,对比了模拟酶蛋白结合物和ＨＥＭＩＮ对过氧化物的测定效果。结果表明,ＨＥＭＩＮ－ＢＳＡ效果最好,其对过氧化物的荧光响应信号约是ＨＥＭＩＮ的２倍,该物质在不改变激发和发射光谱的前提下可增强反应活性,提高反应灵敏度,使方法检测限降低至使用ＨＥＭＩＮ时的１／３左右,最低线性值降至原来的１／５左右,同时,精度亦有所提高。     

离子色谱法测定大气中的甲磺酸

建立了以玻璃纤维膜-KB120气溶胶采样器采集大气中甲磺酸的采样方法;以0.1mmol·l-1H3BO3/0.1mmol·l-1 Na2B4O7为淋洗液的甲磺酸离子色谱分析方法.分析方法的精密度和准确度分别为5%和4%.并实测了青岛冬季大气气溶胶中MSA,SO2-4和NO-3的平均浓度分别为0.10μg·m-3,30.40μg·m -3和17.98μg·m-3.     

Changes of organic acid exudation and rhizosphere pH in rice plants under chromium stress.

The effect of chromium (Cr) stress on the changes of rhizosphere pH, organic acid exudation, and Cr accumulation in plants was studied using two rice genotypes differing in grain Cr accumulation. The results showed that rhizosphere pH increased with increasing level of Cr in the culture solution and with an extended time of Cr exposure. Among the six organic acids examined in this experiment, oxalic and malic acid contents were relatively higher, and had a significant positive correlation with the rhizosphere pH, indicating that they play an important role in changing rhizosphere pH. The Cr content in roots was significantly higher than that in stems and leaves. Cr accumulation in plants was significantly and positively correlated with rhizosphere pH, and the exudation of oxalic, malic and citric acids, suggesting that an increase in rhizosphere pH, and exudation of oxalic, malic and citric acid enhances Cr accumulation in rice plants.