Visible-light-driven photocatalytic inactivation of bacteriophage f2 by Cu-TiO2 nanofibers in the presence of humic acid

Pathogenic viruses in drinking water are great threats to public health. Visible-light-driven photocatalysis is a promising technology for virus inactivation. However, the existing photocatalytic antiviral research studies have mostly been carried out in single-component systems, neglecting the effect of natural organic matter, which exists widely in actual water bodies. In this paper, electrospun Cu-TiO₂ nanofibers were prepared as photocatalysts, and their photocatalytic antiviral performance in the presence of humic acid (HA) was comprehensively studied for the first time. The properties of the reaction mixture were measured during the reaction. In addition, the safety, reliability and stability of photocatalytic disinfection in the mixed system were evaluated. The results showed that the virus removal efficiency decreased with the increase of the HA concentration. The type of reaction solution, such as PBS buffer solution or water, did not affect the removal efficiency noticeably. Under acidic conditions, the electrostatic forces between photocatalysts and viruses were strengthened, leading to higher virus removal efficiency. As the reaction time went on, the pH value in the solution increased first and then tended to be stable, the conductivity remained stable, and the dissolved oxygen increased first and then decreased. The safety test showed that the concentration of Cu ions released into the solution was lower than specified by the international standards. No photoreactivation was observed, and the addition of HA significantly reduced the reutilization efficiency of the photocatalysts.     

污泥与秸秆共基质中温两相厌氧消化特性

以污泥和秸秆为共基质,以沼气产量、ρ（VFA）（VFA为挥发性脂肪酸）和COD_Cr去除率等为指标,探究污泥与秸秆配比（以COD_Cr计,质量比分别为1:0、1:1、2:1、3:1）对中温两相厌氧消化工艺运行效能的影响,以及最佳配比时SRT（污泥停留时间）对产甲烷相厌氧消化稳态特性的影响.结果表明:与污泥试验组相比,添加秸秆试验组的厌氧消化效能均较好;污泥与秸秆的最佳配比为2:1,该稳定状态下产酸相COD_Cr的去除率最高,为17.5%,ρ（VFA）为752 mg/L;产甲烷相COD_Cr的去除率为33.5%,ρ（VFA）为250 mg/L,产气量为47.7 mL/d,总体运行效能较高.在最佳污泥与秸秆配比（2:1）并设定产甲烷相反应器的SRT为20 d时,稳定状态下产甲烷相各组分的变化情况:COD_Cr去除率为41.20%,ρ（VFA）为238 mg/L,产气量为51.3 mL/d,沼气产率为8.4 mL/（d·g）.研究显示,当控制污泥与秸秆配比为2:1、SRT为20 d时,中温两相厌氧消化工艺运行效果良好.      

模拟酸雨对福州平原稻田土壤细菌丰度及多样性的影响

为了探讨酸雨对稻田土壤细菌的影响,以福州平原某稻田为研究对象,测定和分析模拟不同酸度酸雨处理下早、晚稻土壤细菌群落组成及其丰度.结果表明：模拟酸雨处理提高了早稻土壤细菌的多样性,但却降低了晚稻土壤细菌的多样性;酸雨改变了稻田土壤细菌的丰度及群落结构,经模拟不同酸度的酸雨处理,稻田土壤细菌的优势菌属及其丰度并不一致;早稻pH3.5处理组与早稻对照组之间的物种多样性及群落结构差异最大,晚稻pH2.5处理组与晚稻对照组之间的物种多样性及群落结构差异最大;在酸雨作用下,溶杆菌属（Lysobacter）和产黄杆菌属（Rhodanobacter）的丰度明显升高,而马赛菌属（Massilia）的丰度则显著降低,说明溶杆菌属（Lysobacter）和产黄杆菌属（Rhodanobacter）为耐受酸雨的主要菌属,马赛菌属（Massilia）则为受酸雨影响最大的菌属;细菌属H16的相对丰度与土壤电导率（EC）呈极显著负相关（P<0.01）,Lysobacter的相对丰度与土壤pH值呈极显著负相关（P<0.01）,Arenimonas的相对丰度与土壤总有机碳（SOC）呈极显著正相关（P<0.01）.     

安徽铜陵铜尾矿硫形态及硫同位素分布特征

分析讨论了安徽铜陵水木冲S和SP剖面尾矿砂的理化指标、硫形态变化和硫酸根硫同位素组成与分布特征.结果显示：S和SP剖面整体呈酸性,pH值为2.59~6.12和3.50~6.27,由下而上有明显的降低趋势;Eh随剖面由下至上明显升高,范围为66~457和-37~307mV;酸可挥发性硫（AVS）含量为0~62.36和0~3.44mg/g,黄铁矿硫（CRS）含量为0.70~32.30mg/g和0.17~5.39mg/g;AVS与CRS的变化趋势基本一致,随剖面自下而上减少,且AVS先于CRS被氧化.2个剖面元素硫（ES）含量为0~8.83和0~3.62mg/g,随深度变化无明显规律.硫酸根硫（SO₄^2--S）含量为8.44~66.34和8.48~29.87mg/g,自下而上呈降低趋势,且分别在剖面的氢氧化物薄膜层（11.5~16.5cm和18~54cm）出现高值区.2个剖面总硫（TS）含量为9.18~109.69和12.38~37.72mg/g,表层由于淋滤含量较低,底层变化则不大.位于斜坡上的SP剖面TS及各形态硫含量均低于S剖面,表明淋滤对硫含量影响更明显.硫酸根硫同位素δ³⁴S为-3.32‰~13.43‰和-3.08‰~1.80‰,S-9硫酸根δ³⁴S为13.43‰,指示其来自于伴生硬石膏,其余层位δ³⁴S偏负且变幅较小,指示其硫酸根主要来源于硫化物的氧化.     

酸热活化对海泡石吸附水溶液中Cd的影响机制

为增加SP（海泡石）的比表面积并提高其对水溶液中Cd的去除效率,采用HCl对SP进行酸热活化,探索制备HHSP（酸热活化海泡石）最佳的c（HCl）、酸改性时间和热活化温度,并比较SP和HHSP对Cd的吸附动力学和等温吸附特征,通过对吸附前后的SP和HHSP进行SEM-EDS（扫描电镜）、XRD（X射线衍射）和XPS（X射线光电子能谱）分析,以阐明HHSP吸附Cd的微观反应机理.结果表明:0.9 mol/L的HCl改性24 h后,500℃下热活化1 h制备的HHSP吸附性能最佳.准二级动力学模型和Langmuir等温吸附模型均能够很好地描述SP和HHSP对Cd的吸附特征.SP和HHSP对初始质量浓度为50 mg/L的溶液中Cd的去除率在2 h内分别达73.13%和85.96%,在24 h内达到吸附平衡.HHSP的最大饱和吸附量（q_max）为22.147 mg/g,比SP（4.200 mg/g）增加了4.23倍.酸热处理降低了SP的pH和pHpzc（零电荷点）,表明在SP表面吸附活性中心增多.SEM-EDS显示,酸热活化未改变SP的纤维状结构,Cd吸附量由SP的1.57%增至HHSP的2.13%.XPS分析表明,SP和HHSP对Cd的吸附作用包括了表面羟基（-OH）络合作用以及产生CdCO₃、CdCl₂、CdO和Cd（OH）₂沉淀.XRD分析表明,酸改性通过清除SP的CaCO₃成分,比表面积增加,从而增加了HHSP对Cd的吸附量.研究显示,酸热活化可增加HHSP对Cd的吸附效能,为利用HHSP有效控制稻田土壤Cd生物有效性提供了有益途径.      

Modulations in Protein Metabolism of Oziotelphusa Senex Senex During Cypermethrin Intoxication

Cypermethrin induced significant alterations in protein metabolic profiles in the central nervous system (CNS) and pedipalpal muscle (PM) of crab, Oziotelphusa senex senex, following ambient exposure. While total and soluble proteins decreased in CNS and PM, free amino acids, protease, alanine and aspartate aminotransferase (AlAT and AAT) were elevated at 24 h after exposure. These results thus confirm the prevailing protein hydrolysis and transamination in these tissues of crab, as a consequence of cypermethrin intoxication. Restoration of normalcy by 48 h demonstrates the importance of these metabolic events in counteracting the effects of cypermethrin. the results also suggests the safer utilization potential and ecological compatibility of cypermethrin.     

Citric and Oxalic Acids Effect on Pb and Zn Uptake by Maize and Winter Wheat

A pot experiment was conducted to investigate the influence of citric and oxalic acids effect on Pb and Zn uptake by corn and winter wheat. The experiment was employed with citric acid (CA) applied at 3 rates (0, 1.5 and 3.0 mmol kg-1 soil), oxalic acid (OA) at 3 rates (0, 1.5 and 3.0mmol kg-1 soil) and citric acid combined with oxalic acid (1.5 mmol citric acid combined with 1.5 mmol oxalic acid kg-1). Two types of soil were chose in the experiment. One was collected from the agricultural soil near a battery-recycling factory in Anhui province, China (site A) and the other was collected from a Pb-Zn mine residues in Hunan province, China (site B). The results showed that soil pH varied with the different treatment of citric and oxalic acids. However, there were no differences in all the treatments. 3.0mmol CA kg-1 soil addition significantly increased the concentrations of the CaCI2-extractable Pb and Zn and other treatments have no significantly increased. The highest shoot concentrations of Pb and Zn     

EDTA直接滴定测定镍

参考磷酸在345~356℃时有强腐蚀性的特点,采有硫磷混合酸消解矿样,能使样品消解完全。本方法经加标校核证明,检测结果重现性好,准确度高。     

Detection of rubella virus in fetal and placental tissues and in the throats of neonates after serologically confirmed rubella in pregnancy

From 35 therapeutic abortions performed because rubella had occurred at 2–19 weeks of pregnancy, 120 fetal organs, 12 specimens of mixed products of conception, and 15 placentae were tested for rubella virus. Virus was isolated from 10 out of 11 fetuses (91 per cent) from women infected at 2–8 weeks, from 5 out of 8 (63 per cent) infected at 9–10 weeks, and from 2 out of 16 (13 per cent) infected at 11–19 weeks. Hybridization tests for viral RNA on 39 fetal organs from eight cases revealed infection in four additional fetuses. Virus was isolated from only 3 out of 15 aborted placentae, but hybridization tests on six placentae revealed infection in three additional specimens. Hybridization was superior to virus isolation for detecting rubella infection in products of conception and is therefore potentially the better method for examining chorionic villus biopsies. Rubella virus was isolated from the throats of 4 out of 9 infants (44 per cent) infected during the first 12 weeks of gestation, but from none of 13 infected after 17 weeks. Infants in the latter group are unlikely to infect susceptible contacts.