Combined steam-dry reforming of toluene in syngas over CaNiRu/Al2O3 catalysts

Cracking, steam reforming, dry reforming, and combined steam and dry reforming of toluene in model syngas were performed using catalysts to simulate tar removal produced during biomass gasification. The catalysts were prepared by adding Ru, Ca, and Mn to Ni-based catalysts, and their properties were measured using BET, pulse CO chemisorption, XRD and TG. In steam and dry reforming of toluene, a high toluene conversion was observed with increasing Ca content in the catalyst and catalysts containing Ca showed a higher activity than those containing Mn. In combined steam-dry reforming with syngas, 1%CaNiRu/Al₂O₃ indicated a conversion of 93.9% at 800°C.     

模拟酸雨和稀土镧对大豆幼苗的复合影响

采用水培法通过测定大豆幼苗叶片和根的POD活性、MDA含量、H2O2含量,研究了酸雨(AR)和稀土La(Ⅲ)对大豆幼苗POD活性和脂膜过氧化的复合影响。结果表明:单一La(Ⅲ)(RE1/20 mg/L、RE2/60 mg/L、RE3/100 mg/L、RE4/300 mg/L)处理时,低剂量La(Ⅲ)(RE1/20 mg/L)处理下,叶和根中POD活性高于CK而MDA和H2O2含量较之降低,高剂量La(Ⅲ)(RE2/60 mg/L、RE3/100 mg/L、RE4/300 mg/L)处理下,叶和根3项指标均升高。在酸雨(ARl/pH2.5、AR2/pH3.5和AR3/pH4.5)单独作用和RE+AR复合作用影响下,叶和根3项指标均升高;而且AR的pH越低,RE的浓度越高,叶和根中的3项指标增幅越大。RE1和AR复合处理下叶和根中3项指标的增幅低于AR单一处理,其它浓度RE和AR复合处理叶和根中的3项指标增幅高于各自单独作用。单一酸雨处理组各指标变幅为叶>根,单一镧和复合处理组各指标变幅为根>叶。     

城市建筑废物产量估算与预测方法——以海南省为例

文章首先构建了基于建筑面积和产废系数的城市建筑废物产量估算方法体系,进而在二次曲线回归、指数趋势模型、灰色GM(1,1)模型和BP神经网络4种单项预测模型的基础上,建立了以预测有效度为准则的变权重组合模型,以揭示城市建筑废物未来变化趋势。以海南省为例计算和预测了2001-2020年城市建筑废物产量,结果显示:(1)2001-2010年海南省建筑废物总量从219.1万t增加到813.5万t,年平均增长率为12.7%,拆除建筑废物约占建筑废物总产量的70%;(2)2015年海南省建筑废物总量将达到1 621万t,2020年较之增加71.4%,将达到2 769万t;(3)变权重组合预测模型预测有效度好、精度高、误差小,优于4种单项预测模型。预测结果将为海南省建筑废物的处理处置、资源化和综合管理提供科学依据。     

泥蚶不同组织器官对重金属(Cu、Pb、Cd)的富集规律

通过室内半静态暴毒试验,研究三种重金属(Cu、Pb、Cd)的单一与联合胁迫作用下,泥蚶(Tegillarca granosa)不同组织器官对重金属的富集能力、富集途径,以及两两重金属之间的交互作用。结果发现:单一胁迫条件下,泥蚶各组织器官对Cu的富集能力是鳃>内脏团>肌肉,对Pb和Cd的富集能力是鳃>肌肉>内脏团;肌肉和鳃对Pb的富集速率显著(P<0.05)高于内脏团,即泥蚶对Pb的富集可以通过鳃的呼吸作用和体表的渗透作用两条途径实现。联合胁迫条件下,Cd能够拮抗Cu的富集;一定量的Cu也能够在内脏团中发挥作用,拮抗Pb和Cd的累积;在其他各组织中累积的Cu和Cd则不影响Pb的累积,说明Cd和Cu在泥蚶体内以可溶形式存在,而Pb以不溶形式存在。重金属的富集与金属种类、金属浓度、累积途径、生物体的解毒机制等等多种因素有关。     

啤酒废水组合处理工艺的应用与工程实例

概述国内现阶段啤酒生产废水厌氧与好氧组合处理工艺的应用,同时对某厂利用EGSB＋接触氧化＋过滤组合工艺处理啤酒废水的实际应用进行了介绍,处理后排放废水水质达到景观环境用水标准（GB/T18921-2002）,处理啤酒废水费用为0.75元/m3,同时可产生沼气作为能源利用,具有一定的经济效益。     

吹脱-吸附工艺处理钒冶炼高氨氮废水的工程实践

详细介绍了采用常温循环吹脱-移动床吸附工艺处理湖南某钒厂V2O5生产过程排放的高盐高浓度氨氮废水的工艺流程,分析了氨氮去除率的影响因素,并提出了最佳工艺条件。工程实际应用表明:吹脱-吸附工艺对高浓度氨氮废水(Na+浓度为50g/L、NH3-N浓度为13 000mg/L)具有很好的处理效果,出水氨氮浓度低于15mg/L,可达到《污水综合排放标准》(GB8978—1996)的一级排放标准,且高纯度氯化铵的回收利用也大大降低了工程成本。     

生物炭与硅酸钠复合施加抑制水稻对土壤铅吸收富集的机制研究

将水稻秸秆生物炭（RB）、玉米秸秆生物炭（MB）分别与硅酸钠（G）复合施加到从矿区周边采集的铅（Pb）污染农田土壤,通过盆栽试验,比较分析了Pb在土壤-水稻系统各部位中的迁移和累积情况,探讨了生物炭与硅酸钠复合施加抑制水稻对Pb吸收转运的机制.结果表明,与对照组相比,生物炭与硅酸钠复合施加（RBG和MBG）使糙米Pb含量显著降低71.0%~75.6%,且比生物炭或硅酸钠单一施加时的降幅更大.其主要机制为：①生物炭与硅酸钠复合施加提高了土壤pH和有机质含量,促进了土壤对Pb的固定,从而使土壤Pb从弱酸提取态向可氧化态Pb转化,在成熟期RBG和MBG处理分别使CaCl₂溶液浸提的土壤有效Pb含量降低54.3%和60.0%.②生物炭与硅酸钠复合施加降低了DTPA溶液浸提的土壤有效态Fe含量,减少了根表铁膜的数量（DCB-Fe）,而且根系Pb含量与DCB-Fe含量之间呈显著正相关关系,推测生物炭与硅酸钠复合施加使根表用于存储Pb的铁膜减少,从而降低Pb进入根系的几率.③生物炭与硅酸钠复合施加显著降低了分蘖期TF_根-叶和成熟期TF_土-根、TF_茎-糙米、TF_叶-糙米（p<0.05）,阻碍Pb在糙米中累积.此外,生物炭与硅酸钠复合施加显著提高了稻谷质量（p<0.05）.因此,生物炭与硅酸钠复合施加可用于修复铅污染稻田土壤.     

南昌市PM2.5中结合氨基酸的浓度组成及来源

采集了春季南昌市城市和森林地区的大气PM_2.5样品及潜在大气氨基酸排放源（植物和土壤）样品,测定并分析了样品中结合氨基酸（CAAs）的浓度、组成及甘氨酸（Gly）的氮同位素值.结果表明,城市和森林地区PM_2.5中总CAAs的浓度分别为0.507~3.912和0.497~2.647nmol/m³.通过对PM_2.5中CAAs组成占比分析发现,城市和森林地区CAAs组成成分相似,其中Pro、Gly、Ala、Leu和His是PM_2.5中丰富的CAAs物种.结合Gly的氮同位素值可知,城市地区（+0.62‰~+22.67‰）和森林地区（+1.99‰~+23‰） PM_2.5中δ¹⁵N_C-Gly值表现出较大的变化范围.根据大气CAAs潜在排放源δ¹⁵N值清单,本研究中生物质燃烧、土壤源和植物源是PM_2.5中CAAs的主要来源.贝叶斯稳定同位素模型计算源分配结果表明生物质燃烧、土壤源和植物源对城市地区PM_2.5中CAAs的平均贡献为42%、40%和18%,对森林地区PM_2.5中CAAs的平均贡献为38%、38%和24%.     

Suspended particle effects on ClO2/ultraviolet light combined disinfection of effluent

The concentration of suspended solids of effluent often varies in a wide range, therefore the dose of ultraviolet light （UV） in disinfection process needs to be adjusted to meet the disinfection criterion at a high frequency, and the desired disinfection effect is difficult to be ensured. The particles size and particle-associated fecal coliform （F.C.） contribution, and their influence on UV disinfection were investigated when ClO2 and UV combined disinfection process was used. The results showed that suspended solids content had a major impact on UV disinfection efficiency, especially the large particle size fraction. Particles （D〉10μm） associated F. C. were difficult to be disinfected and were the main part of the railings of F.C. inactivation curve. Pre-ClO2 oxidation could reduce the number of particles in effluent, and make large particles decrease to small ones. Therefore, the influence of particles on UV disinfection could be reduced after pre-ClO2 oxidation, and the resistance ability to particle loadings of combined process was enhanced. Moreover, the combined process has a lot of advantages, such as low toxicity, low operational/maintenance costs; it is also convenient to be established in the existing wastewater plant or the new planned one.     

Toxic effects of acetochlor and methamidophos on earthworm Eisenia fetida in phaiozem, northeast China

Introduction W ith the increase in types and am ount of pollutants releasing into soil ecosystem s, research on the joint effects of m ore than one pollutant in soil-plant, soil-anim al and soil-m icroorganism system s is increasingly concerned (Zhou and …