Phytoremediation of Arsenic: Fundamental Studies,Practical Applications,and Future Prospects

Abstract

Arsenic is a toxic element that is naturally present but is also introduced through a variety of anthropogenic activities. Phytoremediation, which is the use of green plants to minimize the impact of toxic substances, has been widely used for arsenic. Phytoextraction employs plants to accumulate toxins into aboveground biomass. Pteris vittata, commonly known as the brake fern, was the first species used for phytoextraction and the most widely investigated, although other Pteris plants have been successfully employed. Several studies have investigated the accumulation of arsenic in food plants to assess possible impact upon human health. Phytostabilization, which involves the use of contaminant-immobilizing soil amendments with plants to reduce contaminant availability, has been successfully employed for arsenic. It is expected that phytoremediation will be employed in the future as a low-cost alternative for the remediation of arsenic in soil.     

含铅金矿和铅精粉中金的测定

采用在样品中加入一定量的硝酸、过滤除去铅对金的干扰,王水溶矿,原子吸收光谱仪测定,可以满足客户对铅精粉中金含量测定的要求。     

混合酸浸提—火争原子吸收法测定土壤中的铅

本文主要研究了土壤中微量元素铅的测定条件，采用混合酸在沸水浴中加热浸提后，直接上机测定，最佳测定条件是水浴温度为１００℃，浸提时间为１２０ｍｉｎ，混合到为ＨＮＯ３＋ＨＣＩ＋Ｈ２Ｏ（１＋１＋２）该方法具有样品前处理简便，测定快速、准确、空白值低等特点，样品加标回收率为９２％－１０２％，ＲＳＤ为０．８３％－６．３８％，并用国家标准物质污染农田土壤标样进行验证，其结果吻合。     

Preparation and Biomedical Applications of Multicolor Carbon Dots: Recent Advances and Future Challenges

Multicolor carbon dots (CDs) as an emerging subclass of carbonaceous nanomaterials have inspired intensive attention due to the fascinating fluorogenic properties of quantum dots, exhibiting great potential applications in the biomedical field. In some cases, reported CDs with blue or green fluorescence are not desirable for further biological applications owing to the conflicting background autofluorescence, low penetration, and relatively large damage to biological tissue. However, multicolor CDs that can work in the longer wavelength region are being developed to address this issue by overcoming the autofluorescence from the cellular components (usually in the blue and green range). In this review, the development of multicolor CDs is described comprehensively, including for red-emissive or NIR-emissive CDs. Additionally, the preparation methods of multicolor CDs are summarized. Moreover, the factors affecting the luminescence of multicolor CDs are discussed in detail, and the biomedical applications are emphasized from multiple perspectives.     

铅锌矿区浮萍中铅的XANES形态分析

南京栖霞山铅锌矿是华东地区最大的铅锌矿床之一,已开采50多年,由此引发的环境问题日益突出。当地环境中铅含量较高,但铅的迁移和毒性机理不明。为此在该地区开展了铅锌矿生物地球化学研究,借助ICP-MS铅含量分析和Pb-LⅢ边XANES形态分析技术,在该污染区发现了耐受并富集重金属的浮萍样品,浮萍中铅的含量为39.4 mg·kg-1。XANES分析和形态拟合结果显示其含硬脂酸铅65%和硫化铅36.9%,从而揭示浮萍样品中铅以含硫的有机酸铅形式存在。     

湿法消解火焰原子吸收法测定黄土复合污染修复植物金盏菊幼苗中的铅和镉

原子吸收光谱法(AAS)广泛应用于重金属分析检测领域,优化测试过程的操作条件,进而保障分析结果的稳定性和重现性,直接关系到预期研究目标的有效实现,建立精准的检测方法往往成为科学研究的首要任务。以金盏菊为黄土区Pb/Cd复合污染修复植物,采用湿法消解-AAS法测定金盏菊幼苗体内Pb/Cd含量,分析所得结果初步揭示金盏菊幼苗对Pb/Cd的富集效应。研究发现:湿法消解-AAS法对Pb/Cd的检出限分别为0.104和0.007 mg·L~(-1),Pb/Cd回收率对应于94.33%~110.78%和97.73%~107.50%之间,同一样品重复测定(6次)的相对标准偏差(RSD)波动于4.11%~4.75%(Pb)和1.11%~2.77%(Cd),表明该方法准确度较好,精密度较高。金盏菊幼苗对Pb的富集能力不强,这可能与Pb的电负性、植物生长周期较短及环境因子等因素有关;但在黄土Cd浓度为50 mg·k~(-1)时,金盏菊幼苗对Cd的平均富集量已达到104.85 mg·kg~(-1)。此外,黄土Pb的共存一定程度上促进了金盏菊幼苗对Cd的吸收,其间可能存在协同作用。所建立的分析方法可以对金盏菊幼苗Pb/Cd含量进行有效检测,预期能为后续研究提供技术支持和质量保障。     

GF-AAS法测定处理污水灌溉土壤中铅最佳基体改进剂的选择及其应用

研究了石墨炉原子吸收法（GF-AAS法）测定一级处理污水灌溉土壤中铅最佳基体改进剂的选择及在最佳改进剂条件下测定污水灌溉土壤中铅的GF-AAS法。试验了磷酸二氢铵, 磷酸铵, 氯化铵, Pd-Mg和磷酸二氢铵+硝酸镁+硝酸铵等基体改进剂对测定一级处理污水灌溉土壤铅的基体改进作用,并根据基体改进剂的改进效果,最佳灰化温度和原子化温度, 选定了最佳基体改进剂和测定条件。40 g·L-1的磷酸二氢铵作为基体改进剂,灰化温度为850 ℃,原子化温度为1 600 ℃时,用氘灯校正背景GF-AAS法进行测定,测定方法的RSD为2.6% ,回收率在92.4%～104%之内。     

化妆品中铅、镉含量的测定

原子吸收光谱法测定了化妆品中的铅和镉 ,铅和镉分别在 0 .5 0— 10 .0 0 μg·m L-1和 0 .2 0— 8.0 0 μg·m L-1范围内有良好的线性关系 ,相关系数分别为 r=0 .9989和 r=0 .9997;标准偏差分别为 RSD≤1.6 7%和 RSD≤ 4 .71% ;标准加入法测定铅和镉的回收率分别为 93.5 %— 10 6 .0 %和 94 .0 %— 10 5 .5 %。方法简单 ,结果准确。     

文具中可溶性铅和镉的测定

采用火焰原子吸收光谱法测定了学生文具中可溶性铅、镉的含量.铅在0.00-10.00μg·mL-1之间,镉在0.00-4.00μg·mL-1之间具有良好的线性关系.方法的RSD≤4.13%.回收率在93.7%-104.5%之间.方法快速简便,结果准确,可用于文具中可溶性铅、镉含量的监测.     

AAS测定纸巾中的铅和镉

本文采用原子吸收光谱法测定纸巾中铅、镉的含量。结果表明，不同纸巾中的污染元素铅、镉的含量不同。同时还对一种纸巾的铅、镉元素进行了回收实验，回收率在92％-104％之间。     

微波消解、石墨炉原子吸收光谱法测定土壤中的铅

采用微波消解系统处理土壤样品,可以大大减少消化试剂的用量及样品的处理时间。石墨炉原子吸收光谱法测定土壤中的铅,以磷酸二氢铵和硝酸镁作混合基体改进剂,可提高灰化温度,消除基体干扰。方法简便,快速,准确度高。铅的测定结果相对标准偏差为0.44%—5.2%;检出限为0.25mg/kg。     

德州市交警发铅水平调查

建立了一种测定交警头发中痕量铅的新方法.研究了在Tween-80存在下,铅与非水溶性试剂meso-四（4-氯苯基）卟啉的显色反应条件,提出了一个高灵敏度测定铅的分光光度法.络合物的最大吸收波长为466nm,组成摩尔比为1∶1,铅含量在0-6μg/10mL范围内有较好的线性关系,表观摩尔吸光系数为1.74×105L·mol-1·cm-1,并将其应用于交警头发中痕量铅的测定.     

Magical Allotropes of Carbon: Prospects and Applications

The invention of carbon and its allotropes have transformed the electronic and optoelectronic industry due to their encouraging properties in a large spectrum of applications. The interesting characteristic of carbon is its ability to form many allotropes due to its valency. In recent decades, various allotropes and forms of carbon have been invented, including fullerenes, carbon nanotubes (CNTs), and graphene (GR). Since the inception of nanotechnology, carbon allotropes-based nanocomposites have become a leading sector of research and advancement due to their unique bonding properties. Fullerenes and CNTs-based polymer nanocomposites have attracted significant research interest due to their vast applications in every sphere of science and technology. Current research impetus reveals that carbon and its allotropes have revolutionized the industry and academia due to their fascinated properties. Recent advances in various aspects of graphene, CNTs, graphene nanoribbons, fullerenes, carbon encapsulates, and their nanocomposites with polymeric materials and their different applications are reported in this review article. Also, current status and future prospects of graphene-based polymer nanocomposites are presented in common along with proper citations extracted from the scientific literature. Moreover, this article is a unique collection of vital information about GR, CNTs, fullerenes, and graphene-based polymer nanocomposites in a single platform.     

卫生纸中铅、镉含量的测定

用原子吸收光谱法对卫生纸中污染元素铅、镉进行了测定。铅在 0 0 0～ 10 0 0 μg·mL- 1 (r =0 9989) ;镉在 0 0 0～ 4 0 0 μg·mL- 1 (r=0 9997)范围内均具有良好的线性关系。本文法的RSD≤ 3 0 8% ,回收率在 94 8%～ 10 4 5 %。方法快速简便 ,结果准确。可用于卫生纸中铅、镉含量的监测     

石墨炉原子吸收法测定化妆品中的铅和砷

本文研究了石墨炉原子吸收法测定化妆品中铅、砷的方法。用湿式消解法消化样品，易掌握。方法简便，灵敏度高。用本方法测定铅的检出限为０．０１０ｎｇ，砷的检出限为０．０１３ｎｇ，相对标准偏差为０．８％－５．２％，方法的回收率为９６．１％－１０５．８％。     

FAAS测定黑木耳中铅和镉

采用原子吸收法测定黑木耳中铅、镉的含量。同时还对一种黑木耳中的铅、镉元素进行了回收实验 ,本方法回收率在 95 %— 10 5 %之间 ,RSD% <5 % ,结果准确     

食用坚果中铅含量的分析

采用原子吸收光谱法对食用坚果中污染元素铅的含量进行了分析。铅在0.00～2.00 μg·mL-1范围内具有线性关系,r=0.999 1,测定铅的RSD≤4.64%,标准加入法测定铅的回收率94.0%～102.0%,方法简单,结果准确。     

ICP-AES测定铁矿石中的铅

采用浓盐酸溶解样品,电感耦合等离子体-原子发射光谱法测定铁矿中的铅元素含量,方法检出限为0.001％.对有证标准物质进行分析,测定值与证书值吻合,相对标准偏差为1.99％-2.21％.