重庆市畜禽粪便及菜田土壤中四环素类抗生素生态风险评价

近年来新型有机污染物抗生素在环境中的残留及对生态环境的风险成为国内外研究的热点.在畜禽养殖业中四环素类抗生素（tetracycline antibiotics,TCs）使用量最大,在畜禽粪便中的残留量也最高.本文采用调查研究结合室内分析,客观评价了重庆市主要大型养殖场畜禽粪便和主要蔬菜基地菜田土壤中3种农用四环素类抗生素[土霉素（OTC）、四环素（TC）和金霉素（CTC）]可能存在的环境生态风险.结果表明,2014年猪粪和鸡粪中的OTC、TC、CTC和TCs总量∑TCs的平均值分别为13.05、91.81、62.48、167.34 mg·kg^-1和4.25、4.6、28.55、37.40 mg·kg^-1.2019年所调查的样品中猪粪和鸡粪中的OTC、TC、CTC和∑TCs平均含量分别为3.39、4.82、5.92、15.95 mg·kg^-1和1.10、1.35、4.22、5.16 mg·kg^-1,相比2014年,2019年重庆市畜禽粪便中TCs含量有大幅度的下降,TCs的检出率也有所降低.鸡粪中的TCs生态风险较猪粪要低,2019年畜禽粪便中的TCs生态风险较2014年大幅度降低,不同抗生素间总体比较,风险商值以CTC > OTC > TC.重庆主要蔬菜基地及周边地区菜田土壤中OTC、TC、CTC和∑TCs的平均含量分别为18.92、39.10、21.80和79.81 μg·kg^-1.TCs含量大小顺序为养殖场附近菜田 > 无公害蔬菜基地 > 普通菜田;在养殖场附近的菜田中,露地TCs含量普遍高于大棚,而在无公害蔬菜基地,TCs含量表现为大棚 > 露地.从菜田TCs的生态风险商值整体上看,各类种植模式下的HQ均<1,即无高风险.3种TCs的HQ值以CTC > OTC > TC.土壤∑TCs含量以叶菜类 > 瓜类 > 茄果类 > 豆类,种植不同类型蔬菜的菜田土壤TCs含量略有差异,可能跟不同蔬菜栽培模式、畜禽粪便种类及施肥量有关系.     

Chemical composition and source apportionment of PM10 and PM2.5 in different functional areas of Lanzhou, China

To elucidate the air pollution characteristics of northern China, airborne PM_10(atmospheric dynamic equivalent diameter ≤ 10 μm) and PM_(2.5)(atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas(Yuzhong County,Xigu District and Chengguan District) of Lanzhou, and their chemical composition(elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM_10(369.48 μg/m~3) and PM_(2.5)(295.42 μg/m~3) were detected in Xigu District in the winter, the lowest concentration of PM_(2.5)(53.15 μg/m~3) was observed in Yuzhong District in the fall and PM_10(89.60 μg/m~3) in Xigu District in the fall.The overall average OC/EC(organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA(the sum of sulfate, nitrate,ammonium, SNA) in PM_(2.5)in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM_(2.5)and PM_10 in Yuzhong County was generally lower than that at other sites in all seasons(0.24–0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization(PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou.     

缺氧—好氧—催化臭氧氧化工艺处理石化厂含盐废水

采用缺氧—好氧—催化臭氧氧化工艺处理某石化厂的含盐废水。实验结果表明：在进水COD为200~350 mg/L的条件下,经生化处理后的出水COD稳定在50~60 mg/L,COD去除率稳定在75%左右;在臭氧投加量为4.5 g/L、V（催化剂Ⅱ）∶V（废水）=1.5∶1的条件下,进行连续催化臭氧氧化后出水COD稳定在20 mg/L以下,COD去除率大于70%,满足DB 61/224—2011《黄河流域（陕西段）污水综合排放标准》。表征结果显示,催化剂表面含有铜元素,比表面积为250.815 m²/g,吸水率为60.9%,经过滤可去除废水中残留的催化剂。     

碳纳米管的免疫毒性研究

碳纳米管已经以各种不同的方式进入我们的生活,因此,对碳纳米管可能给人们的健康与安全带来的影响需要有足够的认识.本文就近年来对碳纳米管引起免疫细胞毒性的研究进展进行综述,为人们进一步认识和更好地应用碳纳米管奠定基础.     

废弃电路板中环氧树脂真空热解规律的研究

真空条件下,应用程序升温管式电炉对废弃电路板中环氧树脂热解规律进行了研究.考察了不同的热解终温(200～700 ℃)、升温速率(5～30 ℃/min)、真空度(以压力表征,3～30 kPa)及保温时间(10～150 min)对热解产物产率的影响.实验结果表明,热解终温是影响热解油产率最重要的因素;选择适当的热解终温(400～550 ℃)、升温速率(15～20 ℃/min)、真空度(15 kPa)及保温时间(30 min)有利于提高热解油产率.     

Biobased Poly(1,3-propylene 2,5-furandicarboxylate)-Carbon Nanotubes Nanocomposites with Enhanced Thermal,Mechanical Properties and Crystallization Behavior

Journal of Polymers and the Environment - Biobased poly(1,3-propylene 2,5-furandicarboxylate) (PPF) and carbon nanotubes (CNTs) nanocomposites were prepared by a solution and coagulation method at...     

Optimal recycle price game theory model for second-hand mobile phone recycling

Human societies develop rapidly through the advancement of technology; however, with these advancements, many problems are emerging. The topic chosen for this study surrounds the e-waste, which has become a major problem around the world. Second-hand and unused mobile phones are a big part of globally generated e-waste. If these devices are properly recycled, they can generate substantial economic and resource value. Yet if they are indiscriminately discarded, they cause a profound environmental impact. Given the current low recovery rate of mobile phones, an increase in recovery rates becomes critical in lessening economic and environmental impacts. Based on the status quo of second-hand mobile phone recycling processes in China, this article analyzes the behavior of individuals and recyclers through a comprehensive static information game theory and finds ways to increase the recycling rate of second-hand mobile phones. The study helps the customers, to clearly identify the recycle price. In case of market, the government policy can be introduced with a reward and punishment mechanism. Furthermore, under the ideological guidance of game theory, this paper also establishes a corresponding price model of second-hand mobile phone recycling based on best response dynamics like search, variable neighborhood search, and hybrid meta-heuristic method. This model shows that the recovery time differences have a significant impact on the recovery price. Moreover, to an extent, this model can promote the possibility and initiative of customers choosing cell phone recycling.

     

Occurrence and distribution of antibiotics in coastal water of the Taizhou Bay,China: impacts of industrial activities and marine aquaculture

Environmental Science and Pollution Research - The occurrence, spatial distribution, and source analysis of antibiotics in global coastal waters and estuaries are not well documented or understood....     

Exploring the interaction relationship between Beautiful China-SciTech innovation using coupling coordination and predictive analysis: a case study of Zhejiang

Environment, Development and Sustainability - Exploring interaction of Beautiful China and SciTech Innovation is an important way to realize economic transformation and sustainable development in...     

Functionalized porous nanoscale Fe3O4 particles supported biochar from peanut shell for Pb(II) ions removal from landscape wastewater

Environmental Science and Pollution Research - The large amounts ofheavy metal from landscape wastewater have become serious problems of environmental pollution and risks for human health. The...