再生水补给型城市景观水体的水生生物群落特征—以圆明园为例

为了解圆明园水环境生态和生物多样性现状,掌握圆明园生态修复区长期恢复状况,于2017年对圆明园水系末端长春园开展水质、大型水生植物、蜻蜓目(Odonata)昆虫、鱼类(Piscium)和软甲动物(Malacostraca)的调查.结果表明:圆明园经过园区内水生生物群落的净化作用,水质基本达到地表Ⅲ类～Ⅳ类水体标准,属于...     

菌株scl-2对苯线磷、哒嗪硫磷和丙溴磷降解的研究

研究了有机磷农药降解菌株Arthrobacter sp.scl-2对苯线磷、哒嗪硫磷和丙溴磷的降解特性,结果表明菌株scl-2可以利用苯线磷、哒嗪硫磷和丙溴磷为唯一磷源生长.菌株scl-2降解苯线磷、哒嗪硫磷和丙溴磷的最适温度均为30℃,哒嗪硫磷的降解在初始pH8时速度最快,而丙溴磷和苯线磷的最适初始pH均为7,偏酸偏碱均不利于菌株对苯线磷、哒嗪硫磷、丙溴磷的降解.利用气相色谱-质谱联机鉴定了苯线磷、哒嗪硫磷、丙溴磷的降解产物,分别为3-甲基-4-甲硫基苯酚、6-羟基-2-苯基-2-氢哒嗪酮和4-溴-2-氯苯酚.     

Influence of Polyol Plasticizers on the Properties of Polyvinyl Alcohol Films Fabricated by Melt Processing

In this work, high-alcoholysis polyvinyl alcohol (PVA) films were fabricated by melt processing and the plasticizing effect of compound polyol plasticizers on PVA were investigated with X-ray diffraction (XRD), differential scanning calorimetry (DSC), rheological measurements, mechanical tests etc. Hydrogen bonding interactions occurred between PVA and plasticizer. With the increase of plasticizer, the flowability of PVA was improved and reached the maximum value at the plasticizer of 20%. Glass transition temperature (T _g) and melting point (T _m) decreased with the increase of plasticizer content. For the heterogeneous nucleation effect of plasticizer, new polymorph of PVA formed. The viscosity was sensitive to the shear rates. The incorporation of plasticizers into PVA resulted in the increase of elongation at break and impact strength, as well as the decrease of tensile strength.     

Removal of methylene blue by coupling black carbon adsorption with TiO2 photodegradation

In this study, the removal of methylene blue (MB) by the coupling of black carbon (BC) and TiO₂ was investigated. The effects of different parameters such as catalyst dose, sorbent, initial concentrations of dye, pH of the solutions, recycles on discoloration, and chemical oxidation demand (COD) reduction of MB were monitored to optimize the reaction conditions. The discoloration and COD conversation rate of MB obtained by the coupling process were 100% after 90?min irradiation. The synergistic effect of MB-adsorption on BC followed by degradation through TiO₂ photocatalysis was proved by FT–IR spectrophotometer. The BC as by-product of natural materials is a promising adsorbent for waste water treatment.     

Determination and QSPR analysis of log Kow and log Koc for fluorine containing benzene derivatives

Octanol‐water partition coefficients (Kow) and soil organic carbon sorption coefficients (Koc) were determined for 14 fluorinated benzene derivatives. Quantitative structure‐property relationships were developed using molecular connectivity indices and quantum chemical parameters to analyze the most significant factors influencing these physico‐chemical properties of the compounds. The substitution by F in benzene derivatives has greater influence on Koc than on Kow.     

Structural effect on photocatalytic degradation of metallised azo dyes in aqueous TiO2 suspension

Three metallised azo dyes were investigated under TiO₂‐photocatalytic and photosensitised conditions in aqueous buffering solutions. The degradation follows apparent first‐order kinetics. The size and strength of intramolecular conjugation determine the light‐fastness of the investigated dyes. Compared with ¹O₂ produced in photosensitised process, the more powerful *OH radicals in TiCO₂ photocatalytic process are highly reactive towards the investigated azo dyes. And as a result, the TiO₂‐photocatalysis makes little less distinction in the degradation kinetic data of the azo dyes compared with the photosensitised degradation of them.     

太原市多环芳烃(PAHs)排放清单与分布特征分析

根据太原市11种主要排放源的排放因子和活动量数据,估算了美国国家环境保护局(US EPA)优先控制污染物清单中16种多环芳烃(PAHs)的年排放量.结果表明2010年太原市16种PAHs的排放量约为332.10t,其中7种致癌性PAHs排放总量为35.11t.从排放源看,生活燃煤和炼焦煤是太原市排放PAHs的主要来源,占总排放量的65%以上.从各地区的PAHs排放情况看,排放量最大的地区是清徐县(87t/a),占总排放的27%.其次为古交市(54t/a)、晋源区(44t/a)、尖草坪区(40t/a).各地区人均收入与单位GDP排放量之间呈负相关 (R2=0.727);各地区PAHs排放量与农村人口之间呈正相关(R2=0.813),从排放谱看,排放以低环PAHs为主(81%),致癌性PAHs占总排放量的10.6%.结果表明,太原市PAHs的排放与太原市特殊的能源结构和人群结构有关.     

建筑垃圾资源化处置技术及装备综述

介绍了国内外有关建筑垃圾资源化处置的相关工艺,并从分选除杂、破碎、筛分、整形强化四方面总结了建筑垃圾资源化处置技术与装备,分析其性能特点及应用范围,为我国相关工艺技术及装备的发展提供参考和借鉴。     

液质联用代谢组学研究多氯联苯和二噁英对大鼠毒性作用

采用基于液质联用(LC-MS)的代谢组学方法研究多氯联苯(PCBs)和2,3,7,8-四氯二苯并-p-二噁英(TCDD)及联合染毒对大鼠生化代谢的影响.对雄性Sprague-Dawley大鼠连续3 d分别灌胃TCDD(10μg.kg-1)、PCBs(Aroclor 1254,10 mg.kg-1)及其混合溶液(10μg.kg-1 TCDD和10 mg.kg-1 Aroclor1254),采用液质联用法在尿液和血浆样本中分别检测出749个和343个色谱峰.PCBs、TCDD及其联合染毒后引起大鼠生化代谢的显著变化.多变量分析结果表明,毒性的大小是:联合染毒>TCDD>PCBs.采用标准物对照、准确质量数、多级质谱碎片离子图和数据库检索的方法,分别在尿液和血浆样本中鉴定出8个和20个生物标记物,表明PCBs和TCDD能导致免疫系统、肝脏和神经系统障碍、干扰脂代谢.