Enhancing p-cresol extraction from soil

Soil washing is a potential technology for rapid removal of organic hydrocarbons sorbed to soils. In this work, p-cresol desorption with different non-ionic surfactants (Tween 80, Brij 30 and Triton X-100) was compared to cyclodextrine and citrate as solubilizer. A series of batch extraction experiments were conducted at 20 °C using the field soil with different extracting solutions at various concentrations to investigate the removal efficiency and to optimize the concentration of the extractant. The use of the different extracting agents was very selective to p-cresol extraction, minimizing soil organic matter releasing and maintaining the natural pH of the soil. The highest asymptotic values of desorption percentages were obtained for Tween 80 and Brij 30 at 48 h. However, Brij 30 ecotoxicity (EC₅₀ = 0.5 mg L⁻¹) is in the same order of that obtained for p-cresol, being this surfactant clearly ruled out. Liquid to solid ratio of 2.5 mL g⁻¹ presented the best extraction results, while concentrations higher than 1 g L⁻¹ for Tween 80 and Citrate did not produce any significant effect on the desorption efficiency. p-Cresol extraction efficiencies higher than 70% and 60% for Tween 80 and Citrate, respectively.     

新型复合混凝吸附药剂对无铅皮蛋废水的处理

皮蛋废水水质相当复杂,既属于含重金属离子废水,又属于中等浓度含盐有机废水.针对皮蛋废水特点,采用混凝+吸附方法预处理皮蛋废水,将PAC与粉煤灰按2:5的投加比混合复制成一种新型复合混凝吸附剂,通过正交实验考察了复合药剂的较佳处理条件.结果表明,在投加量为5 g/L,pH为6.5左右,搅拌时间约为14 min,处理温度为...     

铬渣无害化处理技术研究进展

综述了铬渣无害化处理技术的研究进展,分析了各种技术在实际应用过程中的效果,指出各种处理技术的优缺点,详细介绍了固化法中水泥固化和药剂稳定化两种处理技术,提出开发重金属螯合剂是今后铬渣稳定化处理的研究方向.     

利用废CRT屏玻璃为原料制备泡沫玻璃

以废阴极射线管(CRT)屏玻璃为主要原料,碳黑为起泡剂,采用粉末烧结法制备了低密度保温泡沫玻璃。通过扫描电镜(SEM)、导热系数测定仪等分析手段,研究了起泡剂的用量、发泡温度和发泡时间对泡沫玻璃泡径、密度、热学性能以及机械力学性能的影响。结果表明,在相同烧制工艺条件下,随起泡剂掺加量增加,烧制所得的泡沫玻璃密度成"V"型变化;当其掺加量为0.20%时,泡沫玻璃在密度、孔径分布以及力学性能上均达到最佳。随着发泡温度的提高和发泡时间的延长,密度会逐渐减小,泡沫玻璃的气泡会逐渐增大,以致产生连通现象。当发泡温度为820℃、发泡时间为30min时烧制的泡沫玻璃密度为0.180 g/cm3,导热系数为0.0695 W/(m.K)。     

草酸钾活化法制备榴莲壳活性炭及其表征

以榴莲壳为原料,选择K2C2O4为活化剂,在自制氛围气中进行化学活化制备活性炭。考察了活化剂/原料浸渍比、活化温度与活化时间对活性炭的碘和亚甲基蓝吸附值及得率的影响。结果表明,制备榴莲壳活性炭的理想条件为:活化剂/原料浸渍比1.5∶1、活化温度800℃和活化时间120 min;此时活性炭的SBET(BET比表面积)、总孔容和微孔孔容分别为1 195 m2/g、0.60 cm3/g和0.41 cm3/g。利用比表面和孔隙度分析仪、场发射扫描电镜(FE-SEM)和傅立叶红外光谱法(FT-IR)对活性炭的孔结构特征、微观形貌和表面官能团进行了表征。FE-SEM观测结果显示榴莲壳活性炭孔隙结构发达,且含有丰富的中孔。     

菇渣作为有机栽培基质好氧改性的实验

研究分别以珍珠岩、菌种、猪粪作为添加料,对菇渣静态垛好氧发酵效果的影响。结果表明,菇渣+猪粪处理50℃以上的高温维持时间更长,挥发性固体(VS)和C/N下降幅度更高,有利于菇渣好氧发酵达到腐熟的状态。堆体内温度出现层次效应,高温发酵阶段下层温度高于中层温度,稳定阶段中层温度高于下层,堆体上层温度始终低于中下层。     

一种新型微生物菌剂处理生活污水

利用从食材中筛选纯化的特定微生物制成复合菌剂,在自然、厌氧和曝气3种不同的供氧条件下,添加不同比例的菌剂处理生活污水,以COD和氨氮浓度为参考指标,考察菌剂对污水的净化效果,并分析其原因。结果表明:(1)菌剂投加量在0.5‰～1‰时对污水中COD的去除具有明显促进作用,自然、厌氧和曝气3种条件下,COD去除率最大分别提高了8.77%、11.22%和11.11%;(2)氨氮的去除效果受反应条件影响很大,厌氧条件下菌剂对污水中氨氮的去除作用不明显,自然和曝气条件下,菌剂对氨氮去除效果显著,去除率增幅最高分别达到22.6%和52.28%;(3)以0.5‰的菌剂投加量曝气处理2 d,COD和氨氮的去除率可以分别提高11.11%和14.13%,初步研究显示,该菌剂对生活污水具有较好的净化效果。     

CS-Fe和CS-Fe/Ni的制备及其用于去除钴离子

以氯化铁为铁源,硼氢化钠为还原剂,壳聚糖为稳定剂,采用液相还原法制备壳聚糖稳定纳米铁（CS-Fe）;并以氯化铁为铁源,硫酸镍为镍源,硼氢化钠为还原剂,壳聚糖为稳定剂,采用液相还原共沉淀法制备壳聚糖稳定纳米铁镍（CS-Fe/Ni）。通过SEM、EDS、XRD、FT-IR等表征手段,对所制备的CS-Fe和CS-Fe/Ni的形貌及微观结构进行表征,并以Co²⁺为目标去除物评价CS-Fe和CS-Fe/Ni的反应活性。初步研究表明,制成的CS-Fe含有单质纳米铁,颗粒多数以30~90 nm球形颗粒为主;而CS-Fe/Ni材料中含有纳米铁镍,颗粒多数以30~60 nm球形颗粒为主;在相同的实验条件下,反应60 min,CS-Fe/Ni对Co²⁺的去除率高达100%,但是CS-Fe仅为88%,即CS-Fe/Ni对Co²⁺的去除率比CS-Fe高。     

Closing the Incentive Gap: The Role of Public and Private Actors in Governing Indonesia's Tuna Fisheries

Indonesia is one of the world's largest tuna producing countries, yet regulatory oversight remains weak and management is poor. Incentive-based approaches are a way to improve state-based resource management, but they often require strong government regulation. In this paper, we use principal–agent theory and the notion of the ‘incentive gap’ to explore how incentives could be brought to bear in Indonesia through a combination of private and public actors. With a shared fish stock like tuna, we argue that a double principal–agent problem emerges, where information, asymmetries between various players complicate management. We focus on the problems of adverse selection and moral hazard in three different tuna fisheries in Indonesia to identify the nature of the incentive gap, and comment on the mix of public and private actors currently engaged in tuna fishery governance towards reducing the gap. The double principal–agent problem is a useful yet underutilized framework to understand the dynamics of shared stocks management. In this first application to a developing country fishery, we conclude that information asymmetries cannot be overcome without the involvement of private actors, who are increasingly becoming important in aligning regional and global objectives with those of fishers themselves.     

钻井废水的生物强化处理简

从受钻井废水污染的土壤样品中筛选菌株进行生物处理实验,确定7株菌进行菌剂配伍。通过正交实验剔除可能有抑制作用的菌株,并确定菌剂各组成菌株的最佳配比,制成复合微生物菌剂。考察5种添加物对菌剂的影响,结果显示,当硫酸铵的添加量为20 mg/L时降解率为60%,高于其他添加物。生物强化实验结果显示,投加菌剂的反应器对钻井废水的平均降解率为42%,比未投加菌剂的对照实验的平均降解率（16%）高,而且耐冲击负荷性和降解性能稳定性优于对照实验。