猪粪稻秸超高温预处理促进后续堆肥腐殖化条件优化

以猪粪稻秸为原料,设计超高温预处理温度（75,85,95℃）、时间（2,4,8h）和通风量（0.3,0.6,0.9L/kgTS·h）的三因素三水平正交试验,研究不同超高温预处理条件对猪粪稻秸理化特性及后续模拟堆肥腐殖质生成的影响,结果表明,温度、时间和通气量对猪粪稻秸后续高温堆肥腐殖化系数影响各不相同,各因素对后续好氧发酵累腐殖化系数的影响大小顺序为大小顺序为预处理时间 > 温度 > 通气量;最佳超高温预处理条件为：预处理温度为95℃,停留时间为4h,通气量为0.6L/（kgTS·h）,与CK相比,最佳预处理参数下猪粪稻秸后续高温发酵60d腐殖化系数提高119%,腐殖质、胡敏酸含量分别增加105%、116%,而富里酸含量降低17.2%,结合预处理前后物料理化特性变化规律分析,表明超高温预处理促进了大分子有机物降解为可溶性有机碳,促进了木质纤维素组分降解溶出,促使其更多转化为多酚,同时增加了腐殖质前体还原糖、氨基酸的含量,从而有利于腐殖质的生成.     

稻壳基活性炭催化剂的低温NH3-SCR抗硫性能

以稻壳基活性炭（DAC）为载体,利用等体积浸渍法制备了DAC负载Mn、Ce氧化物的Mn-Ce/DAC脱硝催化剂,并用于氨法SCR反应.采用N₂吸附、X射线衍射（XRD）、X射线光电子能谱（XPS）和程序升温吸附脱附（TPR/TPD）等手段对催化剂的物理化学性能进行了表征.结果发现与商业木屑基活性炭负载Mn、Ce氧化物催化剂（Mn-Ce/MAC）相比,Mn-Ce/DAC具有更高的Ce³⁺/Ce⁴⁺比率、表面化学吸附氧含量以及表面Brønsted酸性位点,这与其优良的低温SCR活性及抗硫抗水性能直接相关.原位红外光谱结果显示在含硫气氛中Mn-Ce/DAC表面的硫酸盐含量明显低于Mn-Ce/MAC,表明前者具有优良抗硫性能.     

Occurrence and distribution of antibiotic resistance genes in the sediments of the East China Sea bays

The coastal area of the East China Sea has experienced rapid urbanization and industrialization in China since 1980 s, resulting in severe pollution of its environments.Antibiotic resistance genes(ARGs) are regarded as a kind of emerging pollutant with potential high risk. The sediment samples were collected from Hangzhou Bay(HB),Xiangshan Bay(XB), and Taizhou Bay(TB) to investigate the spatial occurrence and distribution of 27 ARGs and class I integron–integrase gene(intI1) in the coastal area of the East China Sea. The PCR results showed the frequent presence of 11 ARGs and intI1 in the sediments of the three bays. The qPCR results further showed that sulfonamide resistance was the most prevalent ARG type and antibiotic target replacement and protection were the most important resistance mechanisms in the sediments. Regarding the subtype of ARGs, sulI, tetW, and dfrA13 were the most abundant ARGs, in which sulI was higher in TB(based on both the absolute and relative abundances) and dfrA13 was higher in HB(based on the relative abundances). The network analysis revealed that intI1 had significant correlations with tetC, sulI, sulII, and blaPSE-1. Oil was the key connected factor, which had positive connections with sulI, sulII, and blaPSE-1. In addition, the joint effect of heavy metals and nutrients organic pollutants might be crucial for the fate of ARGs in the coastal sediments.     

Silica-quaternary ammonium “Fixed-Quat” nanofilm coated fiberglass mesh for water disinfection and harmful algal blooms control

Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10~(-3) log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.     

大气污染防治综合科学决策支持平台的开发及应用

大气污染防治和环境治理的紧迫性和复杂性需要科学有效的决策,而以费效评估为标志的综合决策评估模型是支撑环境决策和管理的重要工具.当前以ABaCAS（Air Pollution Control Cost-Benefit and Attainment Assessment System,空气污染控制成本效益与达标评估系统）为代表的综合决策评估模型可以实现对特定减排方案的费效评估,然而无法支持开展基于费效的达标路径优化,以及对应不同环境目标下减排策略的优化制定.针对上述问题,建立了大气污染防治综合科学决策支持平台.该平台以ABaCAS的4个核心模块为基础,建立了新的基于环境目标的反算技术（LE-CO）及优化集成运行模式（ABaCAS-OE）,实现了对不同环境目标要求的减排量反算,并对优化的减排策略下的空气质量改善效果、目标可达性、控制成本及健康收益进行快速估算.将大气污染防治综合科学决策支持平台应用到京津冀及周边地区"2+26"城市,反算了2035年达标要求下的减排情景,以及对应减排方案的费用与效益.结果表明,相较于2015年,预测了2035年京津冀及周边地区的PM_2.5、SO₂、NO_x、VOCs、NH₃排放量需分别减排70%~87%、49%~85%、66%~74%、51%~66%、0~40%才可达标,并且该情景可以带来可观的效益,费用-效益比达3.7.未来大气污染防治综合科学决策支持平台的研究将进一步面向多目标、多行业、多组分、多区域的精细化调控技术,实现经济、能源、排放、浓度、成本、健康、生态、气候一体化的综合决策,以全面支撑我国大气污染防治的综合科学决策.      

Influence of metal ions on sulfonamide antibiotics biochemical behavior in fiber coexisting system

Metal ions and fiber are common compounds in the livestock and poultry manure,which will affect the fate of organic compounds in aqueous environment. However,limited research has addressed the effect of coexisting metal ions and fiber on the biodegradation of sulfonamide antibiotics. Accordingly, a compositing study was performed to assess the effect of metal ions(Fe3+and Cu2+) on the biodegradation of sulfadimethoxine sodium salt(SDM) in the presence of fiber. The enhanced adsorption of SDM onto fiber in the presence of metal ions can be attributed to the π+–π electron donor acceptor(EDA) interaction. The microbial(Phanerochaete chrysosprium) could easily attach onto fiber forming attached microbial, and the degradation rates of SDM of immobilized bacteria in the presence of Fe3 +were 100%, which were significantly higher than those of free bacteria(45%). This study indicates that Fe3 +and fiber could enhance the biodegradation of SDM. Fiber acts as adsorbent, carrier, and substrate which enhanced the removal of SDM.     

A novel graphene oxide-carbon nanotubes anchored α-FeOOH hybrid activated persulfate system for enhanced degradation of Orange II

Persulfate activation has been applied as one of the efficient advanced oxidation processes(AOPs) to remediate polluted environments. In this study, a novel α-FeOOH anchored by graphene oxide(GO)-carbon nanotubes(CNTs) aerogel(α-FeOOH@GCA) nanocomposite activated persulfate system(α-FeOOH@GCA + K_2S_2O_8) was applied for decolorization of Orange Ⅱ(OⅡ). The decolorization of OⅡ was remarkably enhanced to a level of ～ 99% in this system compared with that of pristine α-FeOOH(～ 44%) or GO-CNTs(～18%). The enhanced catalytic activity of α-FeOOH@GCA was due to the formation of a heterojunction byα-FeOOH and GO-CNTs as confirmed by the presence of Fe–O–C chemical bonds. The degradation intermediates of OⅡ were comprehensively identified. The proposed degradation pathway of OⅡ begins with the destruction of the conjugated structures of OⅡ by the dominant reactive oxygen species, surface-bound SO_4~(·-). The decolorization efficiency of OⅡ by the α-FeOOH@GCA activated persulfate system decreased from the first to third cycle of recycling. Ultraviolet(UV) irradiation or introduction of a small amount of Fe~(2+) could restore the activation of this system. The results show that the α-FeOOH@GCA persulfate activation system promises to be a highly efficient environmental remediation method for organic pollutants.     

Template-free synthesis of inorganic hollow spheres at water/“water-brother”interfaces as Fenton-like reagents for water treatment

This paper reports a template-free method to synthesize a series of inorganic hollow spheres (IHSs) including Cu-1, Cu-2, Ni-1, Ni-2 based on mineralization reactions at water/“water-brother” interfaces. “Water-brother” was defined as a solvent which is miscible with water, such as ethanol and acetone. The water/“water-brother” interfaces are very different from water/oil interfaces. The “water-brother” solvent will usually form a homogenous phase with water. Interestingly, in our method, these interfaces can be formed, observed and utilized to synthesize hollow spheres. Utilizing the unique porous properties of the spheres, their potential application in water treatment was demonstrated by using Cu-1 IHSs as Fenton-like reagents for adsorption and decomposition of Congo Red from aqueous solution. The final adsorption equilibrium was achieved after 30 min with the maximum adsorption capacity of 86.1 mg/g, and 97.3% removal of the dye in 80 min after adsorption equilibrium. The IHSs can be reused as least 5 times after treatment by NaOH. This method is facile and suitable for large-scale production, and shows great potential for watertreatment.     

Size-resolved carbonaceous components and water-soluble ions measurements of ambient aerosol in Beijing

A MOUDI-120 sampler was used in Beijing to collect multi-stage samples in the summer and winter of 2013 to 2015. Thirty-three sample sets were collected during the daytime,nighttime, and different pollution levels. The actual relative humidity in the impactors was calculated for the first time. The carbonaceous components(organic and elemental carbon,OC and EC, respectively) and water-soluble inorganic ions(Na~+, NH_4~+, K~+, Mg~(2+), Ca~(2+), Cl~-, NO_3~-,and SO_4~(2-)) were analyzed in each sample. The characteristics of the mass concentration distribution and charge balance were discussed. On the basis of relative humidity in the impactors, aerosols less than 1.0 μm were sampled under relatively dry conditions in most cases. The concentration levels for the chemical species were higher in the winter than in the summer. Three modes(condensation mode, droplet mode, and coarse mode) could be identified from the distributions of NH_4~+, NO_3~-, SO_4~(2-), Cl~-, K~+, OC and EC. The distribution characteristics for the pollution dissipation process were different from the pollution accumulation process. NO_3~-and NO_2~-contributed most of the negative electric charges in the stage below 0.1 μm. In the condensation mode, the cations were dominated by NH_4~+, which was sufficient to balance the anions. In the droplet mode of the heavily polluted samples,the ammonium was not sufficient to balance the anions. In the coarse mode, the positive electric charges were primarily composed of metal cations. The analyzed anions were not sufficient to neutralize the measured cations.     

河北南大港湿地冬季浮游植物群落特征

南大港湿地是北方半人工的滨海沼泽湿地,具有重要的经济价值和生态价值。研究其冬季结冰期及融冰后的浮游生物群落结构的特征,对于了解其水生生态系统的变化有重要意义。2016年1月5日和3月13日河北南大港湿地两次采样的各站位浮游植物样品鉴定结果表明:该湿地浮游植物为硅藻-绿藻型,共鉴定出浮游植物7门,74属,108种。1月结冰期细胞密度范围为（0.26~6.70）×107 /L,均值为2.25×107 /L,主要优势种包括衣藻（Chlamydomonas sp.）、小环藻（Cyclotella sp.）以及细小平裂藻（Merismopedia minima）。3月份融冰后细胞密度范围为（0.35~16.35）×107 /L,均值为4.28×107 /L,主要优势种包括小球藻（Chlorella sp.）、细小平裂藻（Merismopedia minima）、四鞭藻（Carteria sp.）以及针形纤维藻（Ankistrodesmus acicularis）。结冰期前后,浮游植物资源均较为丰富,结构也比较稳定,但融冰后生物多样性要优于结冰期。由于环境因子空间异质性很大,因此同时期湿地内部各个站位物种种类空间分布和细胞密度差异较大。