Preliminary study on the occurrence and distribution of polycyclic musks in a wastewater treatment plant in Guandong, China

The occurrence and distributions of six polycyclic musks were studied in influent, primary and effluent waters from a municipal wastewater treatment plant (WWTP) in Guangdong. Five polycyclic musk compounds, 1,2,3,5,6,7-hexahydro-1,1,2,3,3-pentamethyl-4H-inden-4-one (DPMI), 4-acetyl-1,1-dimethyl-6-tert-butylindan (ADBI), 6-acetyl-1,1,2,3,3,5-hexamethylindan (AHMI), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) were found in wastewater in the WWTP. DPMI, HHCB and AHTN were measured at 0.38-0.69, 11.5-146, 0.89-3.47 microg/l, respectively, in influents. Meanwhile 0.06-0.10 microg/l DPMI, 0.95-2.05 microg/l HHCB, 0.10-0.14 microg/l AHTN were detected in effluents, ADBI and AHMI were also detected in some primary waters and effluents. The results suggested that wastewater from cosmetic plants cause high loadings of polycyclic musks to this WWTP. Under the currently applied treatment technology, the removal efficiencies achieved were 61-75% for DPMI, 86-97% for HHCB and 87-96% for AHTN by transfer to sludge as the main removal route.     

Methane emissions from ricefields as affected by organic amendment, water regime, crop establishment, and rice cultivar

Methane fluxes from Beijing ricefields as affected by organic amendment, water regime, crop establishment method, and rice cultivar were measured with a closed chamber method in 1990, 1991, 1995, and 1996. Total fluxes from plots receiving high organic amendment always exceeded those from the low-input plots. Compared with continuous flooding, intermittent irrigation (there were a few days of no standing water between two irrigations) and constant moisture (the field had no standing water, but remained saturated) reduced methane emission rate by 25.4 and 58.4%, respectively. Methane flux from a dry-seeded rice field was 75.2% lower than from a transplanted ricefield although both dry-seeded rice plots and transplanted ricefields were initially flooded at the same time. Rice cultivars differed in methane emission rates by 9.0–55.7%. Emission rates were positively correlated with aboveground dry matter production and root weight, but not grain yield. Intermittent irrigation and rice cultivar seem to be the most promising methods for mitigating methane emission from ricefields; they do not affect rice yield and are easily implemented at the farm level.     

Comprehensive source identification and apportionment analysis of five heavy metals in soils in Wenzhou City,China

Environmental Geochemistry and Health - The source identification and apportionment of heavy metals (HMs) is a vital issue for restoring contaminated soil. In this study, qualitative approaches [a...     

Environmental and economic assessment of combined biostabilization and landfill for municipal solid waste

Biostabilization can remove considerable amounts of moisture and degradable organic materials from municipal solid waste (MSW), and can therefore be an effective form of pretreatment prior to landfill. The environmental and economic impacts of two combined processes, active stage biostabilization + sanitary landfill (AL), and active and curing stage biostabilization + sanitary landfill (ACL), were compared with sanitary landfill (SL) for MSW with high moisture content. The results indicated that land requirement, leachate generation, and CH(4) emission in the ACL process decreased by 68.6%, 89.1%, and 87.6%, respectively, and the total cost was reduced by 24.1%, compared with SL. This implies that a combined biostabilization and landfill process can be an environmentally friendly and economically feasible alternative to landfill of raw MSW with high moisture content. Sensitivity analysis revealed that treatment capacity and construction costs of biostabilization and the oxidation factor of CH(4) significantly influenced the costs and benefits of the AL and ACL process at an extremely low land price. When the land price was greater than 100 USD m(-2), it became the dominating factor in determining the cost of treatment and disposal, and the total costs of ACL were reduced to less than 40% of those of SL.     

Advances in coastal ocean boundary layer detection technology and equipment in China

Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources, chemical mechanisms, and transport processes of air pollution in land, sea, and atmosphere. We present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent years. China has developed a series of coastal ocean boundary layer detection t...     

水解酸化-厌氧-好氧法处理苯甲酸类化工废水研究

以某化工生产企业废水为例,介绍了水解酸化-厌氧-SBR工艺处理高浓度苯甲酸类生产废水的工程实例,该工程设计规模为70m^3／d,综合进水CODcr高达15000mg／L。实践表明,该工艺处理苯甲酸类废水是一种经济有效的处理方法。利用水解酸化对废水进行预处理,不仅有效地去除了77％的CODcr,还大幅提高了废水的可生化性,使BOD5／COD值由原水的0．33升高到O．54,提高了废水的可生化性,减轻了后续生化处理的负荷,并使最终出水CODcr小于500mg／L,出水可达《污水综合排放标准》（GB8978～1996）三级排放标准。     

Study on machinability of a stellite alloy with uncoated and coated carbide tools in turning

Stellite alloys, which have been widely used in the aerospace, automotive and chemical industries, are hard-to-cut cobalt-based materials. This study investigates the machinability of stellite 12 alloys with uncoated carbide cutting tool grades YG610 (K01-K10) and YT726 (K05-K10/M20) and SANDVIK coated carbide tool SNMG150612-SM1105 under dry cutting conditions. Both wear mechanisms and failure modes of the uncoated and coated tools were investigated with turning experiments. The results show that the coated tool SM1105 remarkably outperforms the uncoated tools; and the cutting tool YG610 generally outperforms YT726 under all cutting conditions. Built-up edge was found with YG610 in some cutting conditions and with SM1105 at cutting speed of 16 m/min. Tool surface burning marks were observed on YT726 at relatively higher cutting speeds. Wear develops slowly with coated tools SM1105 until VB reaches 0.2 mm at most conditions (except at v = 43 m/min, f = 0.25 mm/r). Excessive tool flank typically resulted in tool breakage at the cutting edge for uncoated tools. Abrasive and adhesive wear of cutting tools were observed at low cutting speeds while diffusion and chemical wear occurred at higher cutting speeds.     

高校开设环境教育公共必修课探究

在高校中开设环境教育公共必修课,培养大学生的环境意识,提高环境素质,是实现可持续发展的一个重要措施。本文阐述了环境教育的内涵,论述了国内外高校环境教育的发展概况,分析了高校开设环境教育公共必修课的必要性。以济南市为例,对高校学生和教师分别进行了问卷调查,从学生的环境意识和环境行为、学校开设环境教育公共必修课的现状、师生对环境教育公共必修课的态度等方面进行了调查。结合调查结果。总结出中国高校环境教育公共必修课建设存在的主要问题,如高校对环境教育的重视不足、环境教育课程体系不合理、教学形式单一、师资力量薄弱等,并借鉴国外环境教育的经验,提出完善高校环境教育公共必修课的建议和措施。     

上海市农村富营养化河道生态修复工程研究

用食藻虫引导沉水植物生态修复工程技术对上海市临港新城果园镇里塘河道富营养化水体进行了工程治理和生态修复,辅以种植沉水植物,采取开放式生态修复和治理。每月水质跟踪检测结果表明:该工程治理方法具有显著生态修复效果,水质得到明显改善;COD_Mn、TN、TP在最低平均值时分别比生态修复前下降了60.67%、85.36%、88.74%;氨氮、亚硝态氮和叶绿素a在生态修复中的最低平均值分别为0.088 mg/L、0.024 mg/L和5.31 mg/m³;试验期间,修复区水体TN、TP、NO₂-N、NH₄-N和COD_Mn显著低于对照区,水体透明度（SD）平均为150～180 cm,水质达到国家Ⅱ～Ⅲ类地表水水质标准。     

大气气溶胶碳质组分在线分析仪的研制和应用

大气气溶胶碳质组分主要包括有机碳(Organic Carbon,OC)和元素碳(Elemental Carbon,EC),是大气细粒子的重要组成部分,对大气环境及人体健康具有非常重要的意义.针对目前商品化碳质气溶胶在线分析仪存在的一些问题,研制出大气气溶胶碳质组分在线分析仪(PKUOCEC),实现了对OC和EC的小时浓度测量.仪器同时采用热分解-光学透射(Thermo Optical Transmission,TOT)法和热分解-光学反射(Thermo Optical Reflection,TOR)法分离OC和EC,检测限为0.29μg·m-3(以C计)(采样时间40 min,采样流量8 L·min-1),测量范围最大值为211.50μg·m-3(以C计),可以满足不同环境的大气观测要求.于2016年1月23—31日采用该仪器对北京怀柔大气进行监测,并与商品化在线碳质气溶胶分析仪(RT-4 OCEC,Sunset Lab Inc.)和多角度吸收光度计(5012 MAAP,Thermo Scientific)进行比对.结果显示,PKU-OCEC测得的TC(Total Carbon,TC=OC+EC)和OC浓度均与Sunset-OCEC对应结果显著相关(TC:r=0.986,OC:r=0.984;p0.01),说明两台仪器测量结果具有很好的一致性;Sunset-OCEC测得的EC数据有39.39%低于0.013μg·m-3(以C计),剔除该部分异常值后,其测得的EC数据与PKU-OCEC数据的线性拟合方程由CEC_Sunset=0.9278×CEC_PKU!0.0704(TOT法)和CEC_Sunset=0.9476×CEC_PKU!0.2665(TOR法)变为CE C_Sunset=0.6810×CEC_PKU+1.2842(TOT法)和CEC_Sunset=0.7035×CEC_PKU+1.1179(TOR法),新的方程产生较大正截距,说明Sunset-OCEC的检测限偏高;PKUOCEC测得的EC数据与MAAP测得的BC数据显著相关,其线性拟合度(R2=0.8868(TOT法)、R2=0.8614(TOR法))大于Sunset-OCEC与MAAP的拟合度(R2=0.8047);PKU-OCEC分析仪TOT法和TOR法测得的OC浓度相当(COC_TOR=0.9963×COC_TOT,R2=0.9959).综合结果表明,PKU-OCEC分析仪测量数据可靠,运行稳定且操作简便,可以用于各种环境条件下的大气监测.