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1.
微塑料(MPs)普遍存在于全球各种环境介质中,可以吸附共存的污染物,尤其是有机污染物,进而改变其环境行为和毒性,也可以通过吸附/解吸作用促进污染物在不同介质中的迁移. MPs与有机污染物的吸附影响因素及其作用机理是准确评估MPs和有机污染物环境风险的必要信息.因MPs成分、结构、表面特征等的复杂性及其共存有机污染物的多样性使两者的相互作用十分复杂.本文对MPs在环境介质中的赋存、迁移、吸附有机污染物的影响因素及其相互作用机理进行了系统总结,以期为进一步评估MPs的环境行为和生态风险提供参考.  相似文献   

2.
二次离子质谱(SIMS)分析主要用于半导体、地质等领域材料表面分析,随着科学仪器技术的发展,近年来,SIMS在生命科学领域中得到了越来越广泛的应用。SIMS可以实现对样品表面的质谱分析、化学成像以及深度剖析。三维SIMS成像分析的横向分辨率可达80~100 nm,纵向分辨率1~5 nm。但是,由于缺少特异性指示亚细胞结构的碎片离子,单细胞SIMS成像分析仍然面临着诸多挑战。激光扫描共聚焦显微成像(LSCM)作为一种单细胞成像技术已日趋成熟,可以对单细胞中的荧光分子或者对荧光标记的目标分子、细胞器成像,获得高分辨率亚细胞结构成像图。因而,LSCM在单细胞形貌分析上的优势和SIMS在单细胞化学成像方面的优势可以有效互补,其联合应用能显著提升单细胞分析的应用范围、深度和结果的准确性。本文重点介绍SIMS成像以及SIMS-LSCM联用成像在单细胞成像研究中的应用进展,在总结、评述该领域代表性工作的同时,对SIMS-LSCM联用成像在化学和生命科学研究,特别是在细胞生物学和药物发现领域的应用前景进行了展望。  相似文献   

3.
用X射线光电子能谱(XPS)和二次离子质谱仪(SIMS)等表面分析方法对稀土-6063铝合金进行了研究,发现稀土铝合金的表面为金属铝和铝的氧化物两种形态。稀土及镁两者的协同作用,可以缓和铝合金的氧化程度。SIMS结果表明,加入适量稀土,可以抑制镁在稀土-6063铝合金的表面偏析作用。  相似文献   

4.
今年四月在上海举行的多国仪器仪表展览会上,英国VG公司和KRATOS公司展出了ESCALAB—MK2和XSAM—800测表面元素组份的多功能谱仪,都具有X射线光电子能谱(XPS或称ESCA)、俄歇电子能谱(AES)、二次离子质谱(SIMS)三种主要的表面分析功能,能全面、准确地提供分析结果。  相似文献   

5.
该文综述了基于液相色谱-高分辨质谱联用(LC-HRMS)技术开展的沉积物和颗粒物中有机污染物分析的研究进展,包括LC-HRMS分析策略、分析流程及其在目标物、可疑物和非目标物分析中的实际应用,重点介绍了高通量分析、新兴污染物筛查、不同数据库的特点及应用、未知化合物鉴定置信水平、数据非依赖性采集和优先级策略等内容,初步探讨了该技术目前存在的问题并对其发展和应用进行了展望,以期进一步提高识别和鉴定工作的效率,更好地开展环境样品中有机污染物的筛查和监测研究。文中涉及的高分辨质谱的相关通用性内容,也为该技术在其他领域的应用提供了一定的参考和启发。  相似文献   

6.
基于色谱-质谱联用的新型有机污染物分析方法与技术   总被引:1,自引:0,他引:1  
赵晓峰  李云  张海军  倪余文  陈吉平 《色谱》2010,28(5):435-441
新型有机污染物是目前国内外关注的热点。在发现和分析新型有机污染物方面色谱-质谱联用技术发挥着至关重要的作用。本文对5类新型有机污染物(全氟化合物、药物、饮用水消毒副产物、农药转化产物和新农药、溴化阻燃剂)的主要色谱-质谱联用技术进行了介绍和评价,并对色谱-质谱联用的发展趋势进行了展望。  相似文献   

7.
建立了采用75μm碳分子筛/聚二甲基硅氧烷(CAR-PDMS)纤维的固相微萃取-气相色谱/同位素质谱联用方法测定水中挥发性有机污染物碳同位素。使用浸入式固相微萃取和顶空固相微萃取方法进行实验确定在低浓度条件下最佳δ13C测试方法。通过使用顶空固相微萃取前处理技术进行单体同位素分析分析灵敏度更高,应用CSIA技术对1,2-二氯乙烯,三氯乙烯,四氯化碳进行单体同位素分析,方法的检出限为70μg/L,与样本的标准偏差小于0.3‰。该法适用于水体中微量挥发性有机污染物的同位素组成测定。  相似文献   

8.
毛细管色谱技术,特别是毛细管色谱-质谱联用技术的发展为复杂环境样品的分析提供了有力的工具。近年来,关于多种水体中有机污染物的分析研究国外有不少报导,国内也开展了类似的工作。由于饮用水中有机污染物含量低,成分复杂,报导较少。  相似文献   

9.
范燕  徐昕荣 《化学通报》2021,84(8):857-863
X射线光电子能谱(XPS)广泛应用于材料表面分析表征,因XPS分析方法的主观性相对较强,谱图测试及分析水平会对数据分析质量产生很大影响。为获得更好的数据质量,文章根据国际标准和实际测试经验总结出一种通用于不同类型材料表面分析表征的XPS数据采集和预处理分析思路,以方便测试人员能够更加系统的进行数据采集和分析,为材料研发人员提供更加全面的元素组成信息和谱图解析注意事项,从而更有效地助力材料表面分析研究,该方法对科研工作者分析准确度的提高具有重要的理论意义和实际应用价值。  相似文献   

10.
本文介绍了近年来纳米材料电化学与生物传感器在有机微污染物检测中的研究现状,分析了这些传感器中纳米材料修饰电极的特点,重点阐述了纳米材料在有机微污染物检测中的重要作用,列举了一些纳米材料电化学与生物传感器在有机微污染物检测中的应用。最后对纳米材料电化学与生物传感器用于有机微污染物的检测研究进行了简要评述和展望。  相似文献   

11.
The effect of ultrasonic vibrations applied in situ on the formation of W–WO interface during the exposure of a pure tungsten foil to a low‐temperature oxygen plasma is investigated by photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The tungsten surface was exposed to oxygen plasma at different time intervals and the evolution of the interface formation was studied by angle‐resolved XPS. We show that oxidation without ultrasonic vibrations leads to the formation of a thin oxide film whose growth kinetics is governed by an island growth mechanism. On the other hand, oxide growth in the presence of ultrasonic treatment (UST) appears to follow a layer‐by‐layer growth mode with a distinctly sharper W–WO interface. TOF‐SIMS analysis in this case revealed a reduced amount of water bonded in the film, which suggests an increase in the film's packing density. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

12.
The efficient trapping of photogenerated thioaldehydes with functional shelf‐stable nitrile oxides in a 1,3‐dipolar cycloaddition is a novel and versatile photochemical strategy for polymer end‐group functionalization and surface modification under mild and equimolar conditions. The modular ligation in solution was followed in detail by electrospray ionization mass spectrometry (ESI‐MS). X‐ray photoelectron spectroscopy (XPS) was employed to analyze the functionalized surfaces, whereas time‐of‐flight secondary‐ion mass spectrometry (ToF‐SIMS) confirmed the spatial control of the surface functionalization using a micropatterned shadow mask. Polymer brushes were grown from the surface in a spatially confined regime by surface‐initiated atom transfer radical polymerization (SI‐ATRP) as confirmed by TOF‐SIMS, XPS as well as ellipsometry.  相似文献   

13.
Calcium carbonate has evoked interest owing to its use as a biomaterial, and for its potential in biomineralization. Three polymorphs of calcium carbonate, i.e. calcite, aragonite, and vaterite were synthesized. Three conventional bulk analysis techniques, Fourier transform infrared (FTIR), X‐ray diffraction (XRD), and SEM, were used to confirm the crystal phase of each polymorphic calcium carbonate. Two surface analysis techniques, X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectroscopy (TOF‐SIMS), were used to differentiate the surfaces of these three polymorphs of calcium carbonate. XPS results clearly demonstrate that the surfaces of these three polymorphs are different as seen in the Ca(2p) and O(1s) core‐level spectra. The different atomic arrangement in the crystal lattice, which provides for a different chemical environment, can explain this surface difference. Principal component analysis (PCA) was used to analyze the TOF‐SIMS data. Three polymorphs of calcium carbonate cluster into three different groups by PCA scores. This suggests that surface analysis techniques are as powerful as conventional bulk analysis to discriminate calcium carbonate polymorphs. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

14.
Traditional Korean lacquer films, such as Otchil and Hwangchil, are natural paints extracted from Rhus vernicifera and Dendropanax morbifera trees that grow in the eastern part and on the west and south coast of the Korean Peninsula, respectively. Rhus lacquer has a black color, and Hwangchil has a transparent gold color and a rich camphoric perfume (benzoin). These lacquers have been used since ancient times. In this study, analytical techniques, such as Fourier transform infrared (FT‐IR) spectroscopy, X‐ray photoelectron spectroscopy (XPS), and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS), were used to study the traditional Rhus lacquer and Hwangchil films, avoiding time‐consuming and destructive extraction procedures. To compare the Rhus and Hwangchil lacquers, reference lacquer films were prepared using Rhus and Dendropanax saps. These films were then analyzed using FT‐IR, XPS, and TOF‐SIMS. After establishing the methodology using the reference lacquer films, surface analytical techniques were applied to two different plates painted by an artist. The results suggest that FT‐IR, XPS, and TOF‐SIMS are simple and complementary analytical techniques for the discrimination of old lacquer films. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
The design philosophy and implementation of an ultra high vacuum (UHV), PC controlled, automated in situ fracture stage for a surface analysis system is described. ToF‐SIMS spectra are shown to illustrate the improvement in spectral quality obtained from micro‐compact tension (CT) tests of polymer matrix fracture surfaces produced using the fracture stage in UHV compared to those obtained from a sample tested at air. This system is flexible in that by changing the capacity of the load cell it is possible to reduce or increase maximum loads as the specimen type and material demands. The stage has been designed with instrumental flexibility in mind, utilising commercial SEM‐stub type sample mounts, and can thus be used for AES/SAM and XPS investigations, as well as ToF‐SIMS analysis, in the authors' laboratory. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

16.
超高硫煤有机相中的元素硫与铁复合物的证据   总被引:2,自引:1,他引:2  
运用高性能静态二次离子质谱从中国贵州(六枝)超高硫原煤有机相中观测到元素硫与铁的复合组成离子,由此,首次以确切的实验证据了过去关于煤中可能存在铁-硫复合结构的理论推测,同时本工作还表明,所采用的超高灵敏度和微区离子探针分析方法,适于今后进一步探讨硫及其它有害元素在煤中的复杂化学赋存状态。  相似文献   

17.
Principal component analysis (PCA) of time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) data enables differentiating structurally similar molecules according to linear combinations of multiple peaks in their spectra. However, in order to use PCA to correctly identify variations in lipid composition between samples, the discrimination achieved must be based on chemical differences that are related to the lipid species, and not sample‐associated contamination. Here, we identify the positive‐ion TOF‐SIMS peaks that are related to phosphatidylcholine lipid headgroups and tail groups by PCA of spectra acquired from lipid isotopologs. We demonstrate that restricting PCA to a contaminant‐free lipid‐related peak set reduces the variability in the spectra acquired from lipid samples that is due to contaminants, which enhanced differentiating different lipid standards, but adversely affected the contrast in PC scores images of phase‐separated lipid membranes. We also show that PCA of a restricted data set consisting of the peaks related to lipids and amino acids increases the likelihood that the discrimination of TOF‐SIMS data acquired from intact cells is based on differences in the lipids and proteins on the cell surface, and not sample‐specific contamination without compromising sample discrimination. We expect that the lipid‐related peak database established herein will facilitate interpreting the TOF‐SIMS data and PCA results from studies of both model and cellular membranes, and enhance identifying the origins of the peaks that contribute to discriminating different types of cells. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

18.
Time‐of‐flight Secondary Ion Mass Spectrometry (TOF‐SIMS) has been employed to characterize the surface physical and chemical state of aluminovanadate oxide catalyst precursors (‘V? Al? O’) precipitated at different pH values in the range of 5.5…10. The reference oxide V2O5 has also been studied for comparison purposes. It is shown that the analysis of molecular ion emission yields valuable information on the surface elemental and phase composition. Increasing pH values while precipitating from aqueous precursor solutions are found to result in a monotonic variation of the surface composition, in a progressive hydroxylation of aluminium and vanadium and in an increasing dispersion of vanadium oxide species. SIMS data evaluated on the basis of Plog's valence model of molecular ion emission reveal reduced V4+ states, the fraction of which is dependent on the pH value. The SIMS results are supported by XPS data. The enhancement of the catalytic activity in oxidative propane dehydrogenation over V? Al? O prepared at high precipitation pH is in good correlation with the measured surface characteristics. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

19.
A new perfluorinated acrylate monomer containing the SF5(CF2)6-perfluorinated side chain was synthesized and polymerized into films. Bulk monomer characterization is consistent with the molecular structure based on FTIR, mass spectrometry and NMR analyses. The surface properties of polymer coatings were studied with aqueous wetting (contact angle) and X-ray photoelectron spectroscopy (XPS) methods. The surface composition is shown to be highly enriched in the terminal side chain SF5-chemistry and exhibits properties consistent with a highly apolar, non-wetting perfluorinated polymer surface. Depth-dependent XPS studies using angular-resolved methods (ADXPS) confirmed a non-stoichiometric enrichment of sulfur and fluorine at the film ambient interface, consistent with a surface presence of the terminal SF5-group and possibly film structural anisotropy in the surface zone. Time-of-flight (TOF) secondary ion mass spectrometry (SIMS) analysis supplements the XPS data by showing the presence of all expected SF5-acrylate chemistry components in the outer 15 Å of the film surface.  相似文献   

20.
The main challenges in the manufacture of composite materials are low surface energy and the presence of silicon‐containing contaminants, both of which greatly reduce surface adhesive strength. In this study, carbon fiber (CF) and E‐glass epoxy resin composites were surface treated with the Accelerated Thermo‐molecular adhesion Process (ATmaP). ATmaP is a multiaction surface treatment process where tailored nitrogen and oxygen functionalities are generated on the surface of the sample through the vaporization and atomization of n‐methylpyrrolidone solution, injected via specially designed flame‐treatment equipment. The treated surfaces of the polymer composites were analyzed using XPS, time of flight secondary ion mass spectrometry (ToF‐SIMS), contact angle (CA) analysis and direct adhesion measurements. ATmaP treatment increased the surface concentration of polar functional groups while reducing surface contamination, resulting in increased adhesion strength. XPS and ToF‐SIMS showed a significant decrease in silicon‐containing species on the surface after ATmaP treatment. E‐glass composite showed higher adhesion strength than CF composite, correlating with higher surface energy, higher concentrations of nitrogen and C?O functional groups (from XPS) and higher concentrations of oxygen and nitrogen‐containing functional groups (particularly C2H3O+ and C2H5NO+ molecular ions, from ToF‐SIMS). Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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