铁黄生产中废水处理与废渣的回收利用

介绍了氧化铁黄生产中的废水治理情况，同时其产生的废渣可回收利用。经过治理产生的环境、经济和社会效益显著。     

Mitigation of methane and nitrous oxide emissions from drained irrigated rice fields

One of the important cultural practices that affect methane and nitrous oxide emissions from tropical rice plantations is the water drainage system. While drainage can reduce methane emissions, it can also increase nitrous oxide emissions, as well as reduce yields. In this experiment, four different water drainage systems were compared in a rice field in central Thailand including: (1) continuous flooding, (2) mid-season drainage, (3) multiple drainage and (4) a local method (drainage was done according to local cultural practice) in order to find a system of drainage that would optimize yields while simultaneously limiting methane and nitrous oxide emissions. Methane and nitrous oxide emission were observed and compared with rice yield and physical changes of rice plants. It was found that drainage during the flowering period could reduce methane emission. Interestingly, nitrous oxide emission was related to number of drain days rather than the frequency of draining. Fewer drain days can help reduce nitrous oxide emission. The mid-season drainage and the multiple drainage, with 6.9% and 11.4% reduction in rice yield, respectively, had an average methane emission per crop 27% and 35% lower when compared to the local method. Draining with fewer drain days during the flowering period was recommended as a compromise between emissions and yield. The field drainage can be used as an option to reduce methane and nitrous oxide emissions from rice fields with acceptable yield reduction. Mid-season drainage during the rice flowering period, with a shortened drainage period (3 days), is suggested as a compromise between the need to reduce global warming and current socio-economic realities.     

污泥膨胀形成机理及控制措施研究现状和进展

污泥膨胀现象在全球污水处理厂普遍存在,已成为制约活性污泥工艺发展的重大难题之一.本文总结了丝状细菌研究现状;重点阐述了当前引起污泥膨胀的主要机理;说明了基于这些机理的选择器控制理论;给出了主要的选择器类型.对当前关于污泥膨胀的研究进展和方向,分别从微生物和数学模型2个方面进行了讨论,最后,提出了一系列亟待解决的问题.     

一种新型吸附材料的除磷性能研究

针对水体富营养化的磷，采用吸附法进行处理，制备出一种新型的除磷吸附剂，对水中磷酸盐的吸附性能进行了研究，结果表明，该吸附剂对磷酸盐的吸附速率很高，在酸性条件下，其最大吸附容量为34mg／g。当溶液pH值在1～3范围内，含磷浓度为50mg／L，吸附剂投加量为200mg，接触时间为2h，磷酸盐的去除效率可达98％以上；再生后的吸附剂容量变化不大，是一种具有较高应用价值的新型材料。     

Nitrous oxide emissions from tundra soil and snowpack in the maritime Antarctic

The nitrous oxide emissions were measured at three tundra sites and one snowpack on the Fildes Peninsula in the maritime Antarctic in the summertime of 2002. The average fluxes at two normal tundra sites were 1.1 ± 2.2 and 0.6 ± 1.7 μg N₂O m⁻² h⁻¹, respectively. The average flux from tundra soil site with penguin dropping addition was 3.7 ± 2.0 μg N₂O m⁻² h⁻¹, 3–6 times those from the normal tundra soils, suggesting that the deposition of fresh droppings enhanced N₂O emissions during penguin breeding period. The summer precipitation had an important effect on N₂O emissions; the flux decreased when heavy precipitation occurred. The diurnal cycle of the N₂O fluxes from Antarctic tundra soils was not obtained due to local fluky weather conditions. The N₂O fluxes through four snowpack sites were obtained by the vertical N₂O concentration gradient and their average fluxes were 0.94, 1.36, 0.81 and 0.85 μg N₂O m⁻² h⁻¹, respectively. The tundra soils under snowpack emitted N₂O in the maritime Antarctic and increased local atmospheric N₂O concentrations; therefore these fluxes could constitute an important part of the annual N₂O budget for Antarctic tundra ecosystem.     

Cu/ZnO-RGO的抗菌性能及应用

采用溶胶-凝胶法制备铜锌复合氧化物（Cu/ZnO）,并将Cu/ZnO纳米粒子负载到还原氧化石墨烯（RGO）表面制备Cu/ZnO-RGO复合材料.对Cu/ZnO-RGO复合材料进行表征分析及抗菌性能考察,结果表明,Cu/ZnO纳米粒子成功负载在RGO表面,负载前后Cu/ZnO纳米粒子形态不发生改变,复合材料纯度较高.Cu/ZnO-RGO复合材料对大肠杆菌与金黄色葡萄球菌均有着优异的抗菌性能,可以破坏细菌细胞膜,导致细菌内容物流出,延长细菌进入对数生长期所需的时间.当RGO质量分数为15%?Cu/ZnO-RGO复合材料使用量为120μg/mL时,在循环冷却水系统中作用2h即可拥有96.76%的抗菌率.     

中国江河氧化亚氮的排放及其影响因素

氧化亚氮（N₂O）是一种在大气中存留时间很长的强效温室气体,并被认为是21世纪破坏臭氧层的重要物质之一,气候预测需要对自然与人为排放的包括N₂O在内的温室气体进行全面准确地估算.内陆水体是N₂O的重要排放源,由于人为氮输入的增加,江河N₂O的排放量可能逐年升高.本研究总结了江河N₂O排放速率的研究方法,重点汇总了中国各气候带十大流域江河N₂O的溶存浓度和水气界面交换通量,并与世界其他河流进行比较.结果表明我国江河溶存N₂O浓度为0.3~1591 nmol·L^-1,N₂O释放通量为-12.2~2262.1 μmol·m^-2·d^-1,总体与世界其他江河的范围值具有可比性.在此基础上,进一步分析了江河N₂O的产生和释放机理,探讨了水中溶解性无机氮、溶解氧、有机碳以及水文、地形地貌与气象条件等对江河N₂O产生和释放的影响,并讨论了变化环境下江河N₂O的排放特征.     

纳米刻蚀法制备氧化锰介孔材料及其降解高含盐废水中罗丹明B

为了有效去除高含盐废水中的有机染料污染物,利用有序介孔硅材料作为模板剂,通过硬模板法制备了新型锰系氧化物（MnO_x）介孔材料作为类Fenton催化剂.催化剂的结构表征结果表明,模板剂在锰前驱物溶液中浸渍和后续煅烧成型过程决定了氧化锰介孔材料的结构.浸渍-煅烧成型重复次数越多,MnO_x介孔材料中孔道结构的有序度和氧化锰的结晶度越好.浸渍-煅烧成型次数过少,MnO_x介孔材料中孔道呈现无序状态,比表面积较大但氧化锰结晶度不足;次数过多则形成更为致密的小孔径的孔道结构,从而使MnO_x介孔材料的比表面积减小.由于对罗丹明B（RhB）良好的选择性吸附能力和较多的Mn³⁺/Mn⁴⁺对,具有有序规则孔道的氧化锰介孔材料具有优异的类Fenton催化活性,对高含盐废水中RhB的5 h降解去除率最高可达90%左右.     

制备方法对铁钛复合氧化物磷吸附性能的影响:共沉淀法与机械物理混合法

为了研究制备方法对金属复合氧化物表面性质与吸附性能的影响,本文分别采用共沉淀法与机械物理混合法制备了铁钛复合氧化物CFe-Ti与MFe-Ti.采用SEM、BET、XRD与FTIR等表征技术,研究了两种铁钛复合氧化物CFe-Ti与MFe-Ti的形貌结构、比表面积、表面羟基浓度等表面特性;通过批式吸附实验,考察了其磷吸附性能.结果表明,与纯的氧化物Fe OOH及TiO_2相比,共沉淀法制备的CFe-Ti纳米颗粒更疏松,孔结构更发达,表面羟基浓度更高,CFe-Ti的最大磷吸附容量达40.6mg·g~(-1),高于纯Fe OOH(27.2 mg·g~(-1))与TiO_2(16.7 mg·g~(-1)),分别为其1.5倍和2.4倍,展示了显著的协同效应.而MFe-Ti的形貌结构和表面性质与Fe OOH及TiO_2相比变化不大,其磷最大吸附容量为22.7 mg·g~(-1),不仅明显低于CFe-Ti,且低于纯Fe OOH,表明未产生协同效应.研究也表明,磷在CFe-Ti与MFe-Ti表面的吸附性质未发生变化,均通过形成内层表面络合物而发生了化学吸附.因此,金属复合氧化物的表面性质和吸附性能与其制备方法密切相关,与机械物理混合法相比,共沉淀法是一种更为简单经济制备高效能铁钛复合氧化物磷吸附剂的方法.     

砷氧化菌对胡敏酸络合As (Ⅲ)的氧化作用

土壤砷与土壤微生物相互作用是土壤砷形态转化中需要重点关注的内容之一.为了研究砷氧化菌对胡敏酸络合三价砷[HA-As(Ⅲ)]的作用,设置了不同p H值反应体系,研究砷氧化菌HN-2对HA-As(Ⅲ)作用下,砷的形态变化及其在固液两相中的分配.结果表明,在HA与As(Ⅲ)络合过程中,HA可以将一部分游离态As(Ⅲ)氧化为As(Ⅴ).其中,在p H=7的体系中,As(Ⅲ)被HN-2和HA氧化成As(Ⅴ)的效率最高.在含有砷氧化菌株和不含砷氧化菌株的体系中,0~10 h振荡过程中,HA-As材料均可以释放一部分As(Ⅲ)及As(Ⅴ)进入液相中,同时砷氧化菌可以快速地将As(Ⅲ)氧化为As(Ⅴ),而胡敏酸可以较缓慢地将As(Ⅲ)氧化为As(Ⅴ);反应10~24 h期间,HN-2砷氧化菌可以将络合态HA-As(Ⅲ)转化为游离态As(Ⅲ)并氧化为As(Ⅴ);48 h后反应逐渐达到平衡.固相同步辐射结果可以进一步证明HN-2砷氧化菌对络合态As(Ⅲ)的释放及氧化作用.