Perfluoroalkyl substances in the blood samples from a male population of Sweden

Temporal trends of perfluoroalkyl substances （PFASs） have been determined in the blood samples from several countries globally including a female population in Sweden recently, yet little is known about the time trends in the blood levels of these compounds in Swedish male populations over recent years. In this study, the fourteen target PFASs consisted of four perfluorosulfonates （PFSAs） and ten perfluorocarboxylates （PFCAs） in the whole blood samples, collected from 153 Swedish elderly men during the period between 2008 and 2010, were analyzed via ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. As the dominant PFASs contaminants in the blood samples, perfluorooctane sulfo- nate （PFOS） showed the highest geometric mean （GM） at 8.5 ng/mL, ranging from 1.7 to 29 ng/mL, while blood perfluorooctanoic acid （PFOA） contained the GM of 1.8 ng/mL, ranging from 0.35 to 6.4 ng/mL. Both the levels of these two compounds were lower than those determined in the blood samples of Swedish elderly pop- ulations derived from the late 1990s. According to the temporal trend analysis, over the three years, the blood levels of PFOS in Swedish male populations declined 16 % per annum, while those of perfluoroundecanoic acid （PFUnDA） increased 6.1% per annum, which were con- sistent with those reported previously for the populations from other countries.     

电化学极化对活性炭纤维吸附SCN-的影响

为了去除冶金工业废水中的有害成份,研究活性炭纤维(ACF)电吸附技术。以SCN-为模型物,采用三电极电解池以紫外分光光度法(UV)检测电化学极化对吸附SCN-的影响。实验结果表明,正极化可以强化ACF对SCN-的吸附,而负极化减弱对SCN-的吸附,这一电吸附现象在一定程度上具有可逆性。L angm u ir方程可以描述ACF对SCN-的吸附和电吸附的平衡线。吸附动力学实验表明,与未极化比较,电吸附时ACF在开始阶段(30m in内)能够较快地达到较高的吸附量,使溶液中的SCN-浓度迅速降低。再生过程正极化还可以使活性炭纤维的孔径增大,从而增强活性炭纤维的吸附量。     

环境污染物PFOS可引起大鼠海马干细胞的增殖

目的:观察全氟辛烷磺酰基化合物(PFOS)大鼠海马干细胞增殖情况.方法:利用大鼠腹腔内连续注射不同剂量的PFOS 14天,建立动物模型.以Brdu作标记物,利用免疫组织化学染色的方法检测不同剂量PFOS作用下大鼠海马干细胞增殖情况.结果:以Brdu作标记物,高剂量PFOS作用下大鼠海马内可检测到大量阳性细胞存在,对照组和低剂量PFOS作用下无此阳性结果产生.结论:推测PFOS可引起大鼠海马干细胞的增殖.     

城市污水脉冲电吸附技术深度脱氮

采用脉冲开关电源代替传统电吸附中的直流稳压电源,用活性炭粉末为吸附材料制备电极板,并构建了脉冲电吸附反应装置.比较了脉冲电吸附法和直流电吸附法在吸附去除模拟废水中NO₃-N和NH₃-N的去除率差异,60min内,脉冲电吸附法有更高的去除率.以NO₃-N的去除率为判据,研究了脉冲电流的占空比和频率对氮素去除率的影响.结果表明,在占空比50%、频率10⁴Hz的条件下,NO₃-N的去除率最高.     

铁屑内电解法处理EDTA络合铜废水的研究

采用以铁屑为阳极材料,活性炭为阴极催化剂的铁屑内电解法处理EDTA络舍铜废水。通过中试装置间歇流实验研究了铁屑内电解法对EDTA络合铜的去除效果及其影响因素;利用连续流试验确定最佳反应条件：pH=1．39,停留时间为20min。最佳条件下铜和COD的去除率分别为96．75％和27．29％。内电解法处理EDTA络合铜废水...     

Perfluorooctane sulfonate and perfluorooctanoic acid in the fingernails of urban and rural children

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are two typical perfluorinated compounds (PFCs), found in a wide range of environmental media and organisms, including humans. Human biomonitoring studies of body fluids have revealed that in many areas of the world the general population has been exposed to background levels of PFOS and PFOA. Fingernail has been suggested as a promising biopsy material for assessment of PFCs environmental exposure. In the present study, PFOS and PFOA were quantified using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in fingernails of urban and rural children (N=93) aged 6–12 years. A questionnaire was conducted to determine factors that could influence the PFOS and PFOA levels in the children. The levels of PFOS in urban children were significantly higher (geometric mean (GM)=328 ng/g) than those in rural children (GM=27 ng/g). In contrast, PFOA levels were significantly lower in the urban children compared with the rural children. Significant positive correlation (R=0.53, P<0.05 for urban areas; R=0.71; P<0.001 for rural areas) between the PFOS and PFOA concentrations indicated they had similar sources. The PFOS and PFOA levels were higher in fingernail samples from children aged <9 years than in children aged ⩾9 years. In addition, females had higher PFOA levels than males, in both regions. Other factors that significantly influenced PFOS and PFOA levels were dietary habits and socio-economic background. The results of this study indicate fingernails are a suitable material for biomonitoring of PFCs environmental exposure. However, the levels determined in the fingernail samples need to be first evaluated with regard to the levels determined in other samples, such as human serum.     

稻壳活性炭的制备及在水质净化中的应用

以稻壳为原料制备了高比表面积的粉末活性炭,对其进行了表征,并将其用于自来水源水净化．研究结果表明,稻壳活性炭的碘吸附值和比表面积分别为1010mg/g和1923m^2／g;稻壳炭和商品炭对水中浊度的去除效果基本相同,对高锰酸盐指数的去除率分别为61％和50％;水样处理前后的GC-MS测试结果表明,稻壳炭和商品炭对自来水源水中有机物的去除率分别为71％和45％．制备的稻壳活性炭具有优良的吸附能力．     

Single-trial decoding of imagined grip force parameters involving the right or left hand based on movement-related cortical potentials

Time–domain feature representation for imagined grip force movement-related cortical potentials(MRCP)of the right or left hand and the decoding of imagined grip force parameters based on electroencephalogram(EEG)activity recorded during a single trial were here investigated.EEG signals were acquired from eleven healthy subjects during four different imagined tasks performed with the right or left hand.Subjects were instructed to execute imagined grip movement at two different levels of force.Each task was executed 60 times in random order.The imagined grip force MRCP of the right or left hand was analyzed by superposition and averaging technology,a single-trial extraction method,analysis of variance(ANOVA),and multiple comparisons.Significantly different features were observed among different imagined grip force tasks.These differences were used to decode imagined grip force parameters using Fisher linear discrimination analysis based on kernel function(k-FLDA)and support vector machine(SVM).Under the proposed experimental paradigm,the study showed that MRCP may characterize the dynamic processing that takes place in the brain during the planning,execution,and precision of a given imagined grip force task.This means that features related to MRCP can be used to decode imagined grip force parameters based on EEG.ANOVA and multiple comparisons of time–domain features for MRCP showed that movement-monitoring potentials(MMP)and specific interval(0–150 ms)average potentials to be significantly different among 4 different imagined grip force tasks.The minimum peak negativity differed significantly between high and low amplitude grip force.Identification of the 4different imagined grip force tasks based on MMP was performed using k-FLDA and SVM,and the average misclassification rates of 27%±5%and 24%±4%across 11 subjects were achieved respectively.The minimum misclassification rate was 15%,and the average minimum misclassification rate across 11 subjects was24%±4.5%.This investigation indicates that imagined grip force MRCP may encode imagined grip force parameters.Single-trial decoding of imagined grip force parameters based on MRCP may be feasible.The study may provide some additional and fine control instructions for brain–computer interfaces.     

MWNTs/TiO2对1,2,3-三氯苯的吸附与光降解协同作用研究

以典型氯苯类有机化合物1,2,3-三氯苯(1,2,3-TCB)为目标去除物,研究复合光催化剂MWNTs/TiO2(多壁碳纳米管负载二氧化钛)对其吸附与光催化降解协同作用.结果表明,在不同温度、pH值、复合光催化剂投加量、紫外光光强等影响因素作用条件下,MWNTs对1,2,3-TCB的吸附去除率与纳米TiO2对1,2,3-TCB的光催化降解去除率的叠加理论计算值曲线均在MWNTs/TiO2对1,2,3-TCB吸附与光催化降解共同作用曲线的下方,充分体现了MWNTs/TiO2对1,2,3-TCB的吸附与光降解初始阶段的协同作用.溶液中温度或pH值降低,有利于复合光催化剂对1,2,3-TCB的去除;复合光催化剂投加量增多或紫外光光强增大将提高复合光催化剂对1,2,3-TCB的去除率.     

汉江水体和沉积物中全氟化合物的风险评估

采集汉江旱季和雨季的水样和沉积物,应用超高效液相色谱–三重四级杆质谱,对其中的11种全氟化合物(PFCs)进行检测,研究该区域全氟化合物的污染状况。结果表明,11种全氟化合物都有不同程度的检出,旱季和雨季水样中∑PFCs浓度分别为0.3~23.04和0.16~19.68 ng/L,沉积物中∑PFCs浓度分别为0~55.1和0.99~85.07 ng/g。水样总浓度的最高值出现在汉江汇入长江处的武汉,且武汉采样点的全氟辛酸(PFOA)浓度最高,旱、雨季分别达到22.52和12.52 ng/L。沉积物中总浓度最高值出现在陶岔,且以全氟庚酸(PFHp A)和全氟己酸(PFHx A)为主,沉积物中组分组成的季节差异不大。采用实际检测到的水样中PFOA、全氟辛烷磺酸盐(PFOS)、全氟壬酸(PFNA)、PFHx A和全氟葵酸(PFDA)的浓度以及沉积物中PFOA和PFOS的浓度,运用熵值法,对汉江流域进行全氟化合物污染的风险评估,结果表明,水体和沉积物中的浓度均未达到对生态环境具有风险的水平。     

Effective adsorption of 2,4-dichlorophenol on hydrogenated graphene: kinetics and isotherms

The effective adsorption capability of a hydrogenated graphene （H-Gr） was demonstrated. The H-Gr was firstly prepared by heating graphene （Gr） in a hydrogen flow at 1,000 ℃. The specific surface area, layer number, zeta potential, surface defects, surface compounds groups and elemental ratio of H-Gr were investigated. Taking 2,4-dichlorophenol as a target pollutant, the adsorption ability of H-Gr was evaluated. The results showed that the adsorption kinetics followed the pseudo- second-order equation well. For the adsorption isotherms, the equilibrium data of H-Gr were found to fit to Langmuir model, which was different from the Freundlich model of Gr. The adsorption capacity of H-Gr was high to 287.01 mg/g, almost three times as much as that of Gr, which was benefit from the increase of specific surface area and zeta potential. This work suggests that H-Gr may be a potential candidate for the adsorption of aromatic compounds from water and has great prospect for practical application.     

多壁碳纳米管吸附去除水中1,2,3 - 三氯苯

采用3种不同直径的多壁碳纳米管(MWNTs)对1,2,3 - 三氯苯(TCB)进行吸附实验.结果表明,随MWNTs直径减小,1,2,3 - 三氯苯吸附量增加.实验中发现MWNT(L-8)对TCB的吸附仅需150 min就能基本达到平衡,且最大吸附量达77.5 mg/g;其吸附动力学和热力学过程可分别用假二级反应动力学模型和Freundlich吸附等温线模型来描述.在278 K±1 K,288 K±1 K和298 K±1 K下进行的MWNT(L-8)吸附热力学实验所得到的如平衡常数(K~0)、吉布斯自由能(ΔG~0)、标准焓变(ΔH~0)、熵变(ΔS~0)等热力学参数表明,MWNTs吸附TCB过程为自发吸热反应.当pH值在2～11之间变化时,吸附量基本不变,表明H键对MWNTs吸附TCB过程无显著影响,MWNTs对TCB的强吸附作用可能是MWNTs表面存在的π电子与TCB苯环中的π电子形成π电子对的作用结果.     

基于层层自组装的{壳聚糖/多壁碳纳米管}9/玻碳电极电催化氧化H2 O2

 基于带正电荷的壳聚糖(CHIT)和功能化的带负电荷的多壁碳纳米管(MWNTs)之间的静电吸附,通过层层自组装的方法制备了均一、 稳定的{CHIT/MWNTs}₉多层膜。组装{CHIT/MWNTs}₉多层膜的玻碳(GC)电极用来研究H₂ O₂的电催化氧化,测定H₂ O₂的线性范围﹑响应时间和检测下限分别为：8×10^-6～1.0×10^-2 mol/L (相关性系数为0.997)﹑2 s 和4×10^-6 mol/L。另外,{CHIT/MWNTs}₉/GC电极具有较好的稳定性能。     

黄河下游水体中全氟及多氟烷基化合物的分布特征

系统地研究黄河下游春秋两季水样和沉积物中50种PFASs的分布特征和生态风险。结果表明, PFASs在春秋两季水样中检出的总浓度范围分别为29.83~54.44和16.18~57.81 ng/L, 春秋两季沉积物中PFASs的含量范围分别为18.12~36.16和13.01~36.78 ng/g。在春秋两季占比最高的3类物质在水相和沉积物中均为全氟烷基羧酸(PFCAs)、全氟烷基磺酸(PFSAs)和n:2氟调聚磺酸(n:2 FTSs)。作为新型PFASs, n:2 FTSs在水相和沉积物中均有较高的检出水平。全氟辛酸(PFOA)在水相和沉积物中的主要替代物为短链PFCAs, 六氟环氧丙烷二聚酸(HFPO-DA)则在沉积物中对PFOA有更高的替代趋势; 全氟辛烷磺酸(PFOS)在水相和沉积物中的主要替代物为6:2 FTS。风险熵值法分析结果表明, 水体中各PFASs目标物均未达到环境生态风险水平。     

三相三维电极反应器电解处理酸性橙7模拟废水研究

采用三相三维电极反应器对酸性橙7（Acid Orange 7，A07）模拟废水进行电解处理实验研究．结果表明，在连续5次实验后，AO7模拟废水在该体系中可以达到稳定的处理效果，且线性拟合数据表明脱色率、CODcr，和TOC去除率均能较好地符合一级动力学规律．与二维电极体系相比，三相三维电极体系有利于H2O2类电化学活性物质的生成，因而具有更好的处理效果，其脱色率和CODcr，去除率均可提高30％以上．通过UV—Vis法对AO7在三相三维体系电解过程中的变化进行分析，初步探讨了其降解机理．     

Rapid point-of-use water purification using nanoscale zero valent iron (nZVI) particles

Nanoscale zero-valent iron (nZVI) particles are increasingly being investigated in removing aqueous contaminants. Here, we have demonstrated its inactivation and magnetic removal of bacteria and endotoxins from environmental wastewater samples. Varying dosages (10–1,000 μL) of 0–6 days aged nZVI with a concentration of 5 mg/mL for 2 mL wastewater samples were tested, and relevant removal efficiencies were determined using culturing method for bacteria and limulus amebocyte lysate (LAL) for endotoxins. The supernatants of wastewater samples after reacting with nZVI and subsequent magnetic separations were subjected to spectroscopic, qPCR and DGGE analysis. Overall, high magnetic bacterial removal efficiencies were observed up to 3–4 logs for 1 mL nZVI, while the removal efficiencies decreased sharply down to 0.5 log for 10 μL nZVI. qPCR and DGGE results revealed that higher dosages of nZVI caused severe bacterial cell membrane ruptures, releasing significant amounts of DNA up to 10⁷–10⁸ gene copies/mL when 1 mL nZVI was used. Richer DGGE patterns were observed for higher nZVI dosages. In addition, regardless of the dosages (10–1,000 μL) we have observed more than 90 % removal of endotoxins from the wastewater samples. The described technology has great promise to be used as a point-of-use water purification solution for various purposes.     

Nanoscale structural and electronic evolution for increased efficiency in polymer solar cells monitored by electric scanning probe microscopy

Control of blend morphology at multi-scale is critical for optimizing the power conversion efficiency （PCE） of plastic solar cells. To better understand the physics of photoactive layer in the organic photovoltaic devices, it is necessary to gain understanding of morphol- ogy and the corresponding electronic property. Herein we report the correlation between nanoscale structural, electric properties of bulk heterojunction （BHJ） solar cells and the annealing-induced PCE change. We demonstrate that the PCE of BHJ solar cells are dramatically improved （from 1.3 % to 4.6 %） by thermal annealing, which results from P3HT crystalline stacking and the PCBM aggregation for interpenetrated network. The similar trend for annealing- induced photovoltage and PCE evolution present as an initial increase followed by a decrease with the annealing time and temperature. The surface roughness increase slowly and then abruptly after the same inflection points observed for photovoltage and PCE. The phase images in electric force microscopy indicate the optimized P3HT and PCBM crystallization for interpenetrating network formation considering the spectroscopic results as well. From the correlation between surface photovoltage, blend morphology, and PCE, we propose a model to illustrate the film structure and its evolution under different annealing conditions. This work would benefit the better design and optimization of the morphology and local electric proper- ties of solar cell active layers for improved PCE.     

水蒸气活化对活性炭电吸附脱盐性能的影响

用硝酸对活性炭进行去灰分处理，并用水蒸气进行二次活化，将活性炭制成电极，在电吸附装置中进行电吸附测试。结果表明，二次活化可以提高活性炭的比表面积和孔容，并使得活性炭的单位吸附量从2.92 mg/g提高到4.55 mg/g。活化效果受活化时间和活化温度共同影响，活化1h 的效果最好，提高活化温度有利于提高吸附性能。     

Biological correlates of psychological states among young children: a cross-sectional examination of roles of aspartate transaminase/alanine aminotransferase,insulin, and cytokines

Compared to data on adolescents and adults, limited research has been conducted on biological corre- lates among young children with possible psychological difficulties, especially in Asian countries. By focusing on various peripheral biochemical indicators, we investigated potential biological correlates of psychological states in a community sample of Taiwanese school children aged 6-10 years. In total, 307 students （159 obese children and 148 normal-weight children） were selected from first- and fourth-grade school children in eight elementary schools in the Taipei metropolitan area in 2009. These children underwent a comprehensive health examination, including a physical examination, blood sample analysis, and questionnaire administration in a hospital. Differences in anthropometric and serum biochemical readings were compared between children with average and worse levels on each of the five psychological domains. We found that interleukin （IL）-1β [β = 1.29, 95 % confidence interval （CI） 0.50-2.09], IL-10 （β = 1.61, 95 % CI 〈0.01-3.24）, fasting blood glucose （β = 0.08, 95 % CI 0.01-0.15）, homocysteine （β = 0.63, 95 % CI 0.09-1.18）, and aspar- tate transaminase （AST） （β = 0.15, 95 % CI 〈0.01-0.31） were significantly positively associated with anxiety. In addition, IL-113, insulin, AST, and alanine aminotransam- inase （ALT） were significantly positively associated with depression. Anger and disruptive behaviors were also related to specific biological correlates. Specific biological correlates, including AST/ALT, cardiovascular disease- related variables, and specific cytokines, were linked to particular psychological states among young children in this Asian population. These might provide a route for better understanding the biological aspects of children＇s mental health and might contribute to research on diag- nostic or predictive biomarkers for psychiatric diseases in young children.     

Excellent ethanol sensor based on multiwalled carbon nanotube-doped ZnO

Multiwalled carbon nanotubes(MWNTs)were synthesized through CVD method,and the gas sensitive materials MWNTs/ZnO were obtained by mixing MWNTs and ZnO.The gas sensing properties of the as-prepared materials were investigated.The results show that the gas sensing properties of ZnO sensor are significantly improved by doping MWNTs.The sensitivity,response time and recovery time to 50 ppm ethanol at 260°C are 46,4 and 20 s,respectively.We also examined the selectivity of 0.1 wt%MWNTs-doped ZnO sensors to different gases.The results show that the sensor possesses an excellent selectivity to ethanol.