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1.
It is important to develop efficient technologies on removal of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from water due to their wide distribution and potential threat to human health. In this work, a durable and convenient electrosorption device was designed in continuous flow mode to investigate the adsorption of PFOX (X = A and S) on multiwalled carbon nanotubes (MWNTs) from water under electrochemical assistance. The electrosorption experiments were conducted under different influent and electrolyte concentrations, hydraulic retention time (HRT) and electrode distance to optimize the operation. The results showed that the highest removal efficiencies toward both PFOA and PFOS could come up to 90 % at 1 V. Compared with open circuit (OC) adsorption under the same conditions, the removal efficiencies were improved by 4.9 times (PFOA) and 4.2 times (PFOS) respectively. In addition, the MWNTs electrode was found to be reusable. These findings provide an efficient method to remove PFOX from water by electrosorption in continuous flow mode.  相似文献   

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本文对近年来国内外关于外界物质对血液超氧化物歧化酶(SOD)活性影响的研究进行了综述.得知三硝基甲苯、花粉和紫外线等导致血液SOD活性升高;高压氧、微波辐射、铅和锰等使血液SOD活性降低;同时对SOD活性改变的生理学意义和几种重要的SOD测活方法进行了比较全面的介绍.  相似文献   

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Perfluorinated compounds (PFCs) have been detected in many environmental matrices, biota, and nonoccupationally exposed populations in China recently. However, little is known about the distribution and levels of various PFCs in the general population living in areas where there is PFC exposure. In the present study, the levels and prevalence of ten target PFCs were determined in 227 serum samples from a population of nonoccupationally exposed individuals in Shenzhen, China. Results indicated that human exposure to PFCs was prevalent in Shenzhen. Perfluorooctanoate (PFOA) was the dominant PFC contaminant in the serum samples, with a median concentration of 6.72 ng/mL, followed by perfluorooctane sulfonate (PFOS) with a median concentration of 2.07 ng/mL. Other PFCs were detected at much lower concentrations, with median concentrations ranging from 0.02 to 0.87 ng/mL. Statistically, no significant (P>0.05) gender differences were observed for any of the PFCs. Significant (P<0.01) positive correlations were found between age and serum concentrations of the target PFCs, except for perfluorobutane sulfonate (R = 0.16, P = 0.01), perfluorohexanoic acid (R = 0.08, P = 0.22), and perfluoroheptanoic acid (R = 0.11, P = 0.10). Based on the one-compartment pharmacokinetic model, the total daily intakes of PFOA and PFOS for the general population in Shenzhen were calculated as 0.63 and 0.20 ng/kg body weight/day, respectively.  相似文献   

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比较了3种不同色散递减类型光纤构成的马赫-曾德尔干涉仪(MZI)的先脉冲压缩特性.结果表明:考虑高阶效应时,各种色散渐减光纤构成的MZI的脉冲压缩比例较大,脉座能量也大,对数渐减光纤构成的MZI压缩脉冲质量最好;不考虑高阶效应时,也是对数渐减光纤构成的MZI的压缩脉冲质量最好.  相似文献   

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研究目的:创新要点:研究方法:重要结论:2006年我国上海首次发现番茄黄化曲叶病毒(TYLCV),随后TYLCV迅速蔓延至全国13个省份和自治区。本研究分析了2006至2010年期间TYLCV在我国首发地上海市的分子变异规律。本研究持续五年追踪田间TYLCV,分析TYLCV的全长基因组序列、分子变异及种群遗传结构,为防控TYLCV提供理论依据。2006至2010年从上海采集了26个TYLCV的分离物,利用高保真性的滚环扩增技术获得TYLCV分离物的全长基因组。应用MEGA5等生物信息学软件分析TYLCV的分子变异。TYLCV自然种群具有与RNA病毒相似的突变率,以基因间隔区的分子变异最大,平均突变率为4.81×10-3(见图2和表2)。TYLCV的大部分基因都处于负向选择,但包含在c1开放阅读框内的C4,却与c1承受着不同的选择压而处于正向选择(见图3和表6)。  相似文献   

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溢乳症患者血清PRL含量测定的临床意义   总被引:1,自引:0,他引:1  
目的探讨溢乳症患者血清中垂体泌乳素(Prolactin,PRL)含量检测的临床价值。方法采用PRL免疫化学发光检测法,对47例溢乳症患者(溢乳组)血清进行测定,并与正常哺乳期妇女(哺乳组)及非哺乳期健康妇女(正常组)进行对照比较。结果溢乳组与哺乳组血清PRL含量比较无显著性差异(t=1.077 7,P〉0.05),但溢乳组的PRL异常率明显高于哺乳组(χ2=6.305 9,P〈0.01),溢乳组和哺乳组血清PRL值均明显升高,与正常组比较均有显著性差异(t=6.201 6,P〈0.01 t=5.287 8,P〈0.01) 溢乳组血清PRL异常率均明显高于哺乳组和正常组(χ2=6.305 9,P〈0.01 χ2=13.315 9,P〈0.01),而哺乳组和正常组的血清PRL异常率比较无明显差异(χ2=0.934 8,P〉0.05)。结论溢乳症患者血清中PRL值均呈病理性升高,但PRL异常率的诊断价值明显优于PRL的含量检测。  相似文献   

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探讨红菇子实体提取液对大龄小鼠的抗氧化作用.方法:将大龄小鼠20只随机分为四组:1组为大龄小鼠对照组.仅喂基础饲料和水;其余3组分别为大龄小鼠红菇低剂量组、中剂量组和高剂量组,这三组在喂基础饲料和水的基础上,每天早上9点分别进行人工灌喂红菇提取液100mg/ml、150mg/ml、200mg/ml,灌喂量为0.2ml/10g小鼠体重,连续喂养21天后测定小鼠的脑、心、肝组织内丙二醛(malondialdehyde,MDA)含量;另外再设一小龄小鼠对照组(5只)进行比较.结果:大龄小鼠红菇低剂量组、中剂量组和高剂量组分别与大龄小鼠对照组比较,其大脑、心肌、肝脏组织内MDA含量均有显著性降低(P〈0.051;大龄小鼠对照组与小龄小鼠对照组相比,MDA含量呈极显著差异(P〈0.01);大龄小鼠红菇高剂量组与小龄小鼠对照组相比,MDA含量没有显著差异(P〉(0.05).结论:红菇子实体提取液可降低大龄小鼠组织的MDA含量,基本降低到小龄小鼠的水平,红菇有减少脂质过氧化物对机体的损伤,延缓衰老之功效  相似文献   

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1909年9月建馆,如今迎来100周年华诞的陕西省图书馆,具有大面积全开放式的阅览格局和借阅一体化的的服务模式。陕西省图书馆采用了当今世界最先进的三种技术设备:无线射频识别系统(RFID)、自助借还书机及电子阅报机,使图书馆的读者服务工作上了一个新台阶。  相似文献   

11.
《说文解字》“示”部字反映了上古时期的祭祀文化,而它们都源于人类早期的自然崇拜。通过分析《说文解字》“示”部字的语义,来挖掘上古文化中的自然崇拜现象。  相似文献   

12.
椒江中下游沉积物中多溴联苯醚的分布特征   总被引:2,自引:0,他引:2  
自椒江中下游采集了14个表层沉积物样品,以研究该区域中多溴联苯醚(PBDEs )的含量、分布及其来源.研究结果表明,椒江中下游是PBDEs的高污染区,Σ9 PBDEs(包括BDE28、47、66、99、100、138、153、154、183)浓度范围分别在8.93-45.04 ng/g (干重),平均浓度分别为22.31 ng/g ,是目前世界上已报道沉积物中含量最高的区域之一.此外,在所有被分析的样品中BDE209都是最主要的同系物,表明十溴联苯醚已进入环境并成为污染水平最高的一类PBDEs .  相似文献   

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以α-Al2O3为载体,采用浸渍法制备了Pt催化剂, 考察了Pt催化条件下毫秒级快速重整C2H6的催化反应特性.通过测定重整反应过程中的温度分布情况,讨论了直接反应模型和间接反应模型.结果表明:混合气中燃氧摩尔比(r=n(C2H6)/ n(O2))和反应进气中氮气体积分数(φ(N2))对产物的选择性产生重要影响,随着混合气中r和φ(N2)的提高,C2H4的选择性逐渐增大(最高达70%),H2和CO的选择性(S(H2)、S(CO))降低;混合气体积流量(qV)对产物的选择性也有明显影响,当qV=4 L/min时S(H2)和S(CO)达到最高,分别为40%和75%;C2H6快速催化氧化的产物比例受到多相催化反应与气相反应共同作用.  相似文献   

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该文报道了山东十字花科一新记录植物——芝麻菜Eruca vesicaria(L.)Cav.subsp.sativa(Mill.)Thell.,对其形态识别特征、叶表皮微形态以及种子形状和种皮微形态特征进行了观察和研究.  相似文献   

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《荡寇志》是清中后期保守士人面对西潮涌入、传统文化失落的集体性情感反应的产物,小说作者俞万春以捍卫中国传统文化的基本价值为己任,担负起了文化卫道的使命。但残酷的现实却撕碎了他加强君权、帝制,肃清内乱来重振国威的卫道美梦,小说《荡寇志》便展示了这一特定历史时期各种社会变革思潮下的社会历史文化心态。  相似文献   

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A doubled haploid population, derived from anther culture of F1 hybrid between a typicalindica cv. and ajaponica cv. has been used to investigate the seedling cold tolerance (SCT) in growth cabinet. By dynamically analyzing every day’s survival percentages of the parents and DH lines under 7-d cold plus 9-d normal temperature condition, the quantitative trait loci (QTLs) for SCT have been mapped based on a molecular linkage map constructed from this population. The results show that two parents had significant differences in SCT and the segregation of SCT in DH lines was basically a continuous distribution with most serious injury on the 6th d of the cold treatment. A total of 4 QTLs for SCT have been identified on chromosomes 1, 2, 3 and 4 respectively. The additive effects of qSCT-1, qSCT-2 and qSCT-3 have been contributed by thejaponica cv JX17, but that of qSCT-4 has been contributed by theindica cv ZYQ8. The mechanism of SCT seems complicated since the above 4 QTLs detected at different stages during the treatment. Further study on the genotypes for these SCT QTLs in the DH lines shows transgressive segregation. It is demonstrated that the lines with stronger SCT over JXI7 have 3–4 loci for SCT. Integration of these QTLs into an appropriate variety may lead to a successful rice breeding program for cold tolerance.  相似文献   

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