改性聚乙烯醇吸附镍离子的动力学与热力学研究

研究了自制改性聚乙烯醇对Ni~(2+)的吸附行为,在不同的吸附条件下,探讨相关因素的影响,并对实验数据进行动力学与热力学的拟合。结果表明,室温下,在溶液p H=6.0,NaNO_3的浓度为0.1 mol/L,吸附时间为60 min,液固比为250 m L/g,改性聚乙烯醇对浓度为0.1 mol/L Ni2+的吸附效果好,去除率达到98.05%;当干扰因子设定为0.1 mol/L的Ca(NO_3)_2,对Ni2+的去除率降到59.29%。改性聚乙烯醇对Ni2+的吸附动力学符合准二级动力学方程;Langmuir等温模型的拟合度较高,推测改性聚乙烯醇表面是均一的等质体,计算的最大吸附量为1.35 mmol/g,与实验结果一致;D-R等温模型的拟合度次之,在各温度下,E16 k J/mol,说明改性聚乙烯醇对Ni2+的吸附是以化学吸附为主。通过Van’t Hoff方程的拟合,计算得到的吉布斯自由能以及熵变和焓变表明该吸附过程为吸热化学反应。     

弱磁场强化零价铁对水中偶氮染料脱色降解的作用初探

本文以橙黄Ⅰ、橙黄Ⅱ、橙黄Ⅳ和日落黄4种偶氮染料为目标染料,首次尝试利用外加弱磁场(~20 mT)的方法来强化零价铁脱色降解偶氮染料。结果表明加磁或不加磁时反应过程均符合一级反应动力学。在磁场的存在下,4种偶氮染料的降解速率都较不加磁场时有很大的提高,提高倍数分别为110.67、111.97、59.51和94.00。弱磁场对零价铁降解偶氮染料的促进作用可能是由于外加磁场所产生的洛伦兹力以及零价铁表面产生的感应磁场所产生的磁场梯度力促进了Fe2+的释放,加快了零价铁的腐蚀,促进零价铁释放更多电子和新生态氢,加速了—N=N—键的断裂,从而强化了染料的脱色降解。     

NKY树脂吸附水溶性染料的研究

研究了新型树ＮＫＹ对７种水溶性染料的静态吸附特性，结果表明，该树脂对水溶性染料的吸附具有特性效，通过三常数方程非线性回归实验数据可求出吸附过程的△Ｇ＾０，说明ＮＫＹ对染料的第一层吸附为物理和化学作用并存在的过程，多层吸附为典型的物理吸附。由分民比和温度关系曲线可求得△Ｈ＾０，推导出的标准自由熵为正值，说明吸附是自发进行的。     

大孔树脂吸附法在含酚废水处理中的应用

综述了近１０多年来应用大孔树脂吸附法处理各种含酚工业废水的研究成果和应用实例，包括各种废水的由来与概况、处理工艺条件和应用效果，结果表明，吸附树脂具有吸附效果好，脱附再生容量、性能稳定、适用范围宽、实用性好、可实现综合利用等特点，是处理含酚工业废水的有效方法。     

黄河水体沉积物对邻苯二甲酸二甲酯的吸附

为探讨黄河水体沉积物对邻苯二甲酸二甲酯(DMP)的吸附能力，用批量平衡法研究了沉积物与DMP的吸附作用。结果表明吸附等温线符合Freundlich方程，通过回归分析，分别得出20℃和15℃DMP在黄河水中的等温方程Cs=0．3488×Ceq0.7799和Cs=0．3354×Ceq0.7849。因指数项常数小于1，说明沉积物对DMP的吸附不随溶液中DMP的浓度成正比例增加。黄河水体沉积物对DMP有一定的净化能力。     

低压湿式催化氧化法处理偶氮染料废水

采用低压湿式催化氧化法 (LPWCO)处理高浓度模拟偶氮染料甲基橙溶液 ,考察了温度、H2 O2 浓度、Fe2 浓度等因素对去除效果的影响 ,结果表明 ,LPWCO法的脱色率在 95%以上。同时用一级反应模型拟合了甲基橙溶液脱色的LPWCO反应 ,反应速率方程为 -dc/dt=2 30 5exp ( -2 574 1 8/(RT) )· [H2 O2 ] 0 0 934· [Fe2 ] 0 0 92 6 。     

聚电解质吸附特性的压电传感监测研究

在石英晶体微天平的电极表面修饰SiO2薄层,实时测定阳离子聚电解质均聚二甲基二烯丙基氯化铵在SiO2表面的吸附质量和吸附动力学过程,在此基础上,监测阴离子染料活性艳红K-2BP在预吸附聚电解质膜上的吸附过程,并讨论了溶液离子强度、pH值对聚电解质吸附特性的影响.     

高效染料降解真菌的分离及其在印染废水生物处理中的强化作用

用选择培养基从污水处理厂污泥中筛选出能降解3种染料(OrangeⅠ,OrangeⅡ和酸性大红)的菌株.通过梯度驯化,优选出1株适应能力强、活力旺盛的菌株F2,初步鉴定为腐霉菌.以OorangeⅡ为模式染料,比较不同培养基对降解的影响,发现PDA培养基最合适.通过对降解产物的紫外可见光谱分析,发现腐霉菌F2能彻底降解染料,并优先降解简单结构.另外通过用该菌株作为外源菌强化原染料废水处理的混合菌群,得到良好的处理效果.图5参10     

微电解对不同结构染料脱色效果的研究

采用微电解法研究了染料脱色效率与染料结构的关系.结果表明,脱色的难易程度从染料结构看,依次为偶氮型、蒽醌型＞金属络合型＞半菁阳型.在pH值为5.7-6.0,铁炭比为2:1时,处理效果最好,对100mg·l-1的摸拟染料废水处理1h后,脱色率达到90%以上.     

The functional organization of resin work in honeybee colonies

Resin is an important building material in the nests of honeybees, but little is known about how it is handled within the nest and how its collection is controlled. We studied the functional organization of resin work to better understand how a colony adaptively controls its intake of resin. Two hypotheses have been proposed for how resin collectors stay informed of the need for additional resin: (1) the unloading difficulty hypothesis (resin need is sensed indirectly by the unloading delay) and (2) the caulking activity hypothesis (resin need is sensed directly while engaged in using resin). A falsifiable prediction of the latter hypothesis, but not of the former, is that resin collectors not only gather resin outside the hive but also regularly handle resin inside the hive (taking it from other bees and using it to caulk crevices). Consistent with this prediction are our findings that in the resin sector of a colony’s economy, unlike in the pollen, nectar, and water sectors, there is no strict division of labor between the collectors and the users of a material. Over the course of a day, bees seen collecting resin were also commonly seen using resin. Moreover, we found that the unloading locations of resin collectors are unlike those of water and nectar collectors, being deep inside the hive (at the sites of resin use) rather than at the hive entrance. This arrangement facilitates the engagement in resin use by resin collectors. We conclude that the caulking activity hypothesis is well-supported, but that the unloading difficulty hypothesis also remains viable, for we found that resin collectors experience variable delays in getting rid of their loads, from less than 15 min to more than an hour, consistent with this hypothesis. The stage is now set for experimental tests of these two hypotheses. Both may be correct, which if true will imply that social insect workers, despite their small brains, can acquire and integrate information from multiple sources to improve their knowledge of conditions within the colony.