一种便携快速测量水中铅和镉含量的仪器-ANDalyze

快速测量污染水中重金属元素含量对于监测野外突发污染至关重要.建立了使用以生物酶（DNA酶）为原理的便捷仪器快速测定污染水中铅（Pb）和镉（Cd）元素含量的方法.使用生物酶传感器对标准溶液进行测量,根据溶液推荐和测量浓度之间的线性关系对仪器进行校准后,可测量的质量浓度范围:Pb为2~100 μg/L,Cd为0.1~1.0 mg/L.仪器可以在3~5 min内方便快速完成重金属的现场测量,使用DNA酶可以快速获得污染水中的微量金属元素含量,有利于野外重金属污染的即时测量.     

Mussel‐inspired method to decorate commercial nanofiltration membrane for heavy metal ions removal

Nanofiltration (NF) membranes have been widely used for the treatment of electroplating, aerospace, textile, pharmaceutical, and other chemical industries. In this work, halloysite nanotubes (HNTs) were directly anchored on the surface of commercial nanofiltration (NF) membrane by dopamine modification following advantageous bio‐inspired methods. SEM and AFM images were used to characterize the HNTs decorated membrane surface in terms of surface morphology and roughness. Water contact angle (WCA) was employed in evidencing the incorporation of HNTs and dopamine in terms of hydrophilicity or hydrophobicity. Augmentation of HNTs was found to obviously enhance the hydrophilicity and surface roughness resulting in improved water permeability of membrane. More importantly, the rejection ratios of membrane also increased during the removal of heavy metal ions from wastewater. The permeability and Cu²⁺ rejection ratio of modified NF membrane were as high as 13.9 L·m^?2·h^?1·bar^?1 and 74.3%, respectively. Incorporation of HNTs was also found to enhance the anti‐fouling property and stability of membrane as evident from long‐term performance tests. The relative concentration of HNTs and dopamine on membrane surface was optimized by investigating the trade‐off between water permeability and rejection ratio.     

Ligandless,deep eutectic solvent‐based ultrasound‐assisted dispersive liquid‐liquid microextraction with solidification of the aqueous phase for preconcentration of lead,cadmium, cobalt and nickel in water samples

A green and efficient sample preparation method using a deep eutectic solvent‐based ultrasounds‐assisted dispersive liquid–liquid microextraction with solidification of the aqueous phase followed by high performance liquid chromatography analysis was developed for preconcentration and determination of heavy metals in environmental samples. In the proposed method, a novel, low density deep eutectic solvent was prepared by mixing trihexyl(tetradecyl)phosphonium chloride and thiosalicylic acid at a molar ratio of 1:2 and used both as an extractant and complexing agent. Ultrasound was used to disperse the extractant in the aqueous phase of the sample. Then, the phases were separated by centrifugation, after which the aqueous phase was frozen and the surface extractant phase was dissolved in a small volume of acetonitrile and subjected to liquid chromatographic analysis. The proposed method provided precisions (relative standard deviation, n = 5) in the range of 2.6–4.7%. The limit of detection were 0.05, 0.13, 0.06, and 0.11 µg/L for Pb(II), Cd(II), Co(II), Ni(II), respectively. The enhancement factors were equal to 154, 159, 162, and 158 for lead(II), cadmium(II), cobalt(II), and nickel(II), respectively. The accuracy of the proposed method was evaluated using certified reference materials (CA011b – hard drinking water, NIST 1643e – trace elements in water, TMRAIN‐04 – simulated rain sample).     

成都平原典型地区水果-土壤重金属污染特征研究

为摸清成都平原土壤-水果系统中重金属污染水平和富集特征,通过对成都平原典型地区333个水果作物及其根部表层土壤中Hg、As、Pb、Cd、Cu、Cr和土壤理化指标的测定,结果表明：（1）研究区土壤养分整体呈现出有效磷和碱解氮较丰富,有机质和速效钾较缺乏的特征,可通过增施有机肥、地面覆草、施用绿肥等方式提升土壤肥力水平。（2）研究区土壤重金属存在部分点位超标,以Cd的超标率最高。土壤重金属单因子评价污染等级为清洁,土壤综合污染指数评价污染等级为中度污染,其主要贡献为Cd。研究区重金属存在一定程度的富集,Cd和Hg的污染指数高,潜在生态风险强,应重点关注土壤Cd污染和Hg含量水平的增加趋势,将Cd污染作为下一步土壤风险管控和修复治理的重点目标。（3）研究区水果Pb、Cd的超标率分别为5.7%、7.8%,不同水果Pb、Cd的超标率差异显著,草莓Cd的超标率最高。研究区水果中重金属未对成人构成非致癌健康风险,而水果中的As和Cu对儿童构成了非致癌健康风险,As和Cu对水果重金属非致癌总指数的贡献超过70%,应特别关注水果中As和Cu的管控,以免造成较大的食源性危害。（4）重金属在水果与土壤中的含量水平关联性较低,水果中重金属的含量与水果富集重金属的能力关联度极高,应进一步查明水果重金属与土壤重金属形态的关系,并结合调整水果种植结构、筛选重金属低积累水果品种等方式降低水果重金属的健康风险。     

Is Genetic Engineering a Route to Enhance Microalgae-Mediated Bioremediation of Heavy Metal-Containing Effluents?

Contamination of the biosphere by heavy metals has been rising, due to accelerated anthropogenic activities, and is nowadays, a matter of serious global concern. Removal of such inorganic pollutants from aquatic environments via biological processes has earned great popularity, for its cost-effectiveness and high efficiency, compared to conventional physicochemical methods. Among candidate organisms, microalgae offer several competitive advantages; phycoremediation has even been claimed as the next generation of wastewater treatment technologies. Furthermore, integration of microalgae-mediated wastewater treatment and bioenergy production adds favorably to the economic feasibility of the former process—with energy security coming along with environmental sustainability. However, poor biomass productivity under abiotic stress conditions has hindered the large-scale deployment of microalgae. Recent advances encompassing molecular tools for genome editing, together with the advent of multiomics technologies and computational approaches, have permitted the design of tailor-made microalgal cell factories, which encompass multiple beneficial traits, while circumventing those associated with the bioaccumulation of unfavorable chemicals. Previous studies unfolded several routes through which genetic engineering-mediated improvements appear feasible (encompassing sequestration/uptake capacity and specificity for heavy metals); they can be categorized as metal transportation, chelation, or biotransformation, with regulation of metal- and oxidative stress response, as well as cell surface engineering playing a crucial role therein. This review covers the state-of-the-art metal stress mitigation mechanisms prevalent in microalgae, and discusses putative and tested metabolic engineering approaches, aimed at further improvement of those biological processes. Finally, current research gaps and future prospects arising from use of transgenic microalgae for heavy metal phycoremediation are reviewed.     

核磁共振分析技术在重油表征中的研究进展

重油的开发和利用日趋重要。只有对重油的结构和组成有充分的了解,才能合理地利用这部分有限的资源。核磁共振谱图能够直接反映出碳、氢及杂原子所处的化学环境,且分析简便、快捷,从而成为沥青、渣油等重油的结构组成分析的有力工具。本文概述了近年来核磁共振技术在重油结构和组成分析方面所做的主要研究。     

城市土壤不同颗粒中重金属的分布及其对人体吸入重金属的影响

采集了9个不同质地的城市土壤,按颗粒大小分为6个粒级,分别测定了4种重金属(Cu、Cd、Co和Pb)的全量和有效态含量。结果表明,细颗粒中重金属有明显的富集,其中<0.002 mm粒组的重金属含量约为土壤的1.57~13.95倍。有效态重金属占其总量的比例一般是0.250~0.125 mm和0.125~0.050 mm粒组高于其它粒组。质地对重金属在不同颗粒中的分配有很大的影响;虽然重金属含量一般是质地较黏的土壤高于质地不黏的土壤,但砂质土壤中细颗粒组分中的重金属的含量却一般要高于黏质土壤的相应粒组。因此,在相同的重金属含量条件下,砂质土壤对人体的潜在影响要远高于黏质土壤。     

Strongly Basic Anion Exchange Resin Based on a Cross-Linked Polyacrylate for Simultaneous C.I. Acid Green 16, Zn(II), Cu(II), Ni(II) and Phenol Removal

The adsorption ability of Lewatit S5528 (S5528) resin for C.I. Acid Green 16 (AG16), heavy metals (Zn(II), Cu(II) and Ni(II)) and phenol removal from single-component aqueous solutions is presented in this study to assess its suitability for wastewater treatment. Kinetic and equilibrium studies were carried out in order to determine adsorption capacities, taking into account phase contact time, adsorbates’ initial concentration, and auxiliary presence (NaCl, Na₂SO₄, anionic (SDS) and non-ionic (Triton X100) surfactants). The pseudo-second-order kinetic model described experimental data better than pseudo-first-order or intraparticle diffusion models. The adsorption of AG16 (538 mg/g), phenol (14.5 mg/g) and Cu(II) (5.8 mg/g) followed the Langmuir isotherm equation, while the uptake of Zn(II) (0.179 mg^1−1/nL^1/n/g) and Ni(II) (0.048 mg^1−1/nL^1/n/g) was better described by the Freundlich model. The auxiliary’s presence significantly reduced AG16 removal efficiency, whereas in the case of heavy metals the changes were negligible. The column studies proved the good adsorption ability of Lewatit S5528 towards AG16 and Zn(II). The desorption was the most effective for AG16 (>90% of dye was eluted using 1 mol/L HCl + 50% v/v MeOH and 1 mol/L NaCl + 50% v/v MeOH solutions).     

The Utilization of Algae and Seaweed Biomass for Bioremediation of Heavy Metal-Contaminated Wastewater

The presence of heavy metals in water bodies is linked to the increasing number of industries and populations. This has serious consequences for the quality of human health and the environment. In accordance with this issue, water and wastewater treatment technologies including ion exchange, chemical extraction, and hydrolysis should be conducted as a first water purification stage. However, the sequestration of these toxic substances tends to be expensive, especially for large scale treatment methods that require tedious control and have limited efficiency. Therefore, adsorption methods using adsorbents derived from biomass represent a promising alternative due to their great efficiency and abundance. Algal and seaweed biomass has appeared as a sustainable solution for environmentally friendly adsorbent production. This review further discusses recent developments in the use of algal and seaweed biomass as potential sorbent for heavy metal bioremediation. In addition, relevant aspects like metal toxicity, adsorption mechanism, and parameters affecting the completion of adsorption process are also highlighted. Overall, the critical conclusion drawn is that algae and seaweed biomass can be used to sustainably eliminate heavy metals from wastewater.     

重金属污染土壤植物修复的强化措施研究进展

植物修复是一种有着巨大市场潜力的治理重金属污染土壤的技术,由于影响植物修复效率的因素较多,至今实际应用还很少。针对目前植物修复技术的不足,主要从植物本身的性能、重金属的生物有效性以及农艺管理措施等三方面,综述了近年来国内外有关植物修复强化措施的研究进展,并展望了今后该领域的研究方向。