温度对改性矿物吸附剂脱除气态汞影响

以蛭石、丝光沸石、膨润土及经改性后各物质为吸附剂,N2气氛下,在固定床实验台上进行了对烟气中单质汞脱除的实验研究,主要考察了温度的改变对改性矿物吸附剂脱除气态汞的影响。研究结果显示,膨润土、蛭石对汞的吸附基本不受温度的影响;未改性的吸附剂对汞的吸附能力均比较差;温度的提高有利于改性吸附剂对单质汞的脱除,说明改性后的吸附剂的脱汞过程以化学吸附为主;真正起作用的活性组分CeO2占据了丝光沸石的大部分表面积和空隙;丝光沸石经CuO改性前后吸附能力几乎未发生变化。     

Characteristics of lead geochemistry and the mobility of Pb isotopes in the system of pedogenic rock–pedosphere–irrigated riverwater–cereal–atmosphere from the Yangtze River delta region,China

Knowledge of the characteristics of Pb and its isotopic transfer in different compartments is scant, especially for the mobility of Pb isotopes in the geochemical cycle. The present study characterizes differential Pb transport mechanism and the mobility of Pb isotopes in the pedogenic parent rock–pedosphere–irrigated riverwater–cereal–atmosphere system in the Yangtze River delta region, by determining Pb concentration and Pb isotopic ratios of pedogenic parent rocks, fluvial suspended particle matter, tillage soils, soil profiles, irrigated riverwater, fertilizer, Pb ore, cereal roots and grains. The results show that Pb isotopes in the geochemical cycle generally follow the equation of ²⁰⁸Pb/²⁰⁶Pb = −1.157 × ²⁰⁶Pb/²⁰⁷Pb + 3.46 (r² = 0.941). However, Pb isotopes have different mobility in different environmental matrixes. Whereas in the pedosphere, the heavier Pb (²⁰⁸Pb) usually shows stronger mobility relative to the lighter Pb, and is more likely to transfer into soil exchangeable Pb fraction and carbonates phase. The lighter Pb shows stronger transfer ability from soil to cereal grain via root compared to the heavier Pb. However, the cereal grains have lower ²⁰⁶Pb/²⁰⁷Pb and higher ²⁰⁸Pb/²⁰⁶Pb ratios than root and tillage soil, similar to the airborne Pb and anthropogenic Pb, implying that a considerable amount of Pb in cereal grains comes from the atmosphere. The estimate model shows that 16.7–52.6% (average: 33.5%) of Pb in rice grain is the airborne Pb.     

Haze is a risk factor contributing to the rapid spread of respiratory syncytial virus in children

This study investigated whether respiratory syncytial virus (RSV) infection in children was associated with ambient temperature and air pollutants in Hangzhou, China. A distributed lag non-linear model (DLNM) was used to estimate the effects of daily meteorological data and air pollutants on the incidence of RSV infection among children. A total of 3650 childhood RSV infection cases were included in the study. The highest air pollutant concentrations were in January to May and October to December during the year. The yearly RSV-positive rate was 10.0 % among children with an average age of 4.3 months. The highest RSV-positive rate occurred among patients 0 to 3 months old. Children under 6.5 months old accounted for 80 % of the total patients infected by RSV. A negative correlation was found between ambient temperature and RSV infection, and it was strongest with minimum ambient temperature (r = ?0.804, P < 0.001). There was a positive correlation between the infection rate and the particulate matter (PM) 2.5 (r = 0.446, P < 0.001), PM10 (r = 0.397, P < 0.001), SO₂ (r = 0.389, P < 0.001), NO₂ (r = 0.365, P < 0.001) and CO (r = 0.532, P < 0.001). The current study suggested that temperature was an important factor associated with RSV infection among children in Hangzhou. Air pollutants significantly increased the risk of RSV infection with dosage, lag and cumulative effects.     

呼吸计量法对甲醇和葡萄糖为基质的ASM1参数测定

污水水质和污泥特性不同,活性污泥1号模型(ASM 1)参数的测定结果也不相同。研究以甲醇和葡萄糖为基质,对分别经过甲醇和葡萄糖驯化的活性污泥,通过呼吸计量法测定高食微比、中食微比和零食微比下的氧利用速率(OUR)随时间变化的曲线。确定了异养菌产率系数(YH)、异养菌最大比增长速率(μ^H)和衰减系数(bH),并根据YH、μ^H和bH的测定结果和对中食微比下OUR曲线的数值拟合确定了异养菌半饱和常数(ks)、最大比水解速率(kh)和慢速可生物降解底物水解的半饱和常数(KX)。研究结果表明,在20℃下,采用甲醇和葡萄糖为基质测得的YH、bH、μ^H、ks、KX和kh分别为0.53、0.48、5.75、0.9、0.03、3.0和0.87、1.03、2.27、4.45、0.01、7.0。YH、bH、μ^H和ks的值与ASM1中城市污水的推荐值0.67、0.62、6.0、20.0不同,反映了不同基质对参数测定结果的影响。对于慢速可生物降解有机物(Xs)含量低的水质来说,KX和kh对生化反应过程影响不大,可采用ASM1模型的推荐值。     

不同生育期美人蕉-微生物修复富营养化水体

生物修复水体富营养化,尤其是植物和微生物联合修复为目前水体富营养化治理方面的研究热点。不同生育期植物和微生物联合修复鲜见报道。研究不同生育期美人蕉和固定化微生物对富营养化水体的联合修复作用。结果表明,营养生长期和开花期美人蕉-微生物组处理前3天,富营养化水体中不同形态氮和磷浓度快速下降,用于美人蕉生长发育。从富营养化水体氮去除效果来看,营养生长期美人蕉-微生物联合处理去除效果略好于开花期,对磷的去除效果相反。美人蕉吸收氮元素为营养器官利用,其营养器官全氮增长量与生殖器官（花）形成显著差异（P<0.05）。花是美人蕉全磷含量最高、全磷增长量最高的器官,其全磷含量和全磷增长量与营养器官均形成显著差异（P<0.05）。实验结果表明,不同生育期美人蕉-微生物联合处理对氮和磷的吸收利用存在差异。     

感应热固定床CWPO处理染料废水的催化剂制备及其性能

感应热固定床(IHFB)作为新型热传递方式下非均相反应器,利用感应加热铁磁材料将热量传递至液相,形成固液界面高温微反应区,实现有机废水低能高效降解。实验以海绵铁为感应内核,淀粉为碳源,0.2 mol/L硝酸镍为浸渍溶液,按照一定固液比采用浸渍焙烧法制备了C包覆表层负载NiO的感应热催化剂(mNiO/C),对mNiO/C材料的形态结构进行了SEM、ES和XRD表征。结果表明,铁碳比(Fe/C)3∶1、浸渍固液比1∶1、500℃下焙烧2 h,重复包覆3次所得的mNiO/C材料结构最稳定、催化活性最大。并以直接紫D-BL模拟废水为进水,考察了流动状态下感应热固定床催化湿式过氧化氢氧化法(CWPO)降解染料废水的性能,在最优条件下,染料降解率高达80%以上。     

基于人工神经网络和遗传算法研究锰过氧化酶脱色甲基橙

基于锰过氧化物酶(MnP)氧化脱色偶氮类染料的原理,实验研究MnP对甲基橙的脱色工艺,采用人工神经网络(ANN)和遗传算法(GA)建立脱色模型并优化工艺。建立的ANN模型的误差、相关系数、均方根误差和绝对平均偏差分别为0.0009、0.9971、1.21和6.82,模型有效且能够用于预测和工艺优化。采用GA对ANN模型进行数值寻优,得到的最佳工艺条件为酶液量0.6 mL,Mn2+浓度4 mmol/L,H2O2浓度0.49 mmol/L。该条件下脱色率达到(90.74±0.59)%。ANN耦合GA有效地建立了锰过氧化物酶脱色甲基橙的模型,并优化了工艺参数,为甲基橙脱色的研究提供一定参考。     

中国石油HSE信息系统现场实施方案

对于中国石油这样的大型企业,信息系统建设的成功与否,除取决于系统的软件和硬件之外,一整套行之有效的现场实施方案也尤为重要。文章从中国石油HSE信息系统现场实施策略、实施流程、实施效果等方面进行阐述,总结出了一套适合中国石油业务管理信息系统的现场实施方案。     

几种矿区复垦农业利用模式的可持续性分析与比较——以唐山开滦煤矿为例

本文从可持续发展的思想出发 ,分别运用西方经济学和环境经济学方法对唐山开滦煤矿的复垦农业模式的特征及其可持续性进行了分析与比较 ,并据此为该区域的土地复垦提出了一种可行的方案建议。     

Impact of clouds and aerosols on ozone production in Southeast Texas

A radiative transfer model and photochemical box model are used to examine the effects of clouds and aerosols on actinic flux and photolysis rates, and the impacts of changes in photolysis rates on ozone production and destruction rates in a polluted urban environment like Houston, Texas. During the TexAQS-II Radical and Aerosol Measurement Project the combined cloud and aerosol effects reduced j(NO₂) photolysis frequencies by nominally 17%, while aerosols reduced j(NO₂) by 3% on six clear sky days. Reductions in actinic flux due to attenuation by clouds and aerosols correspond to reduced net ozone formation rates with a nearly one-to-one relationship. The overall reduction in the net ozone production rate due to reductions in photolysis rates by clouds and aerosols was approximately 8 ppbv h^?1.