原子光谱/元素质谱在生命分析中的应用进展

原子光谱/元素质谱是元素分析的强有力手段,其在生命分析领域的应用也越来越广泛。在单细胞元素分析方面,相关研究工作主要关注元素在单细胞中的分布和形态变化;在元素标记策略分析领域,利用原子光谱（atomic spectrometry, AS）和电感耦合等离子体质谱（inductively coupled plasma mass spectrometry, ICP-MS）实现对小分子、核酸、蛋白质等目标分析物的高灵敏检测是研究热点;在金属药物分析领域,ICP-MS为研究金属药物在生物体中的摄入、分布、代谢和排泄等过程提供了便利,也为进一步阐明药物作用机理以及金属药物的设计和改进提供了数据支持;在生物元素成像领域,ICP-MS与激光剥蚀技术（laser ablation, LA）联用,可以对生物样品进行原位分析和微区分析,结合有机质谱实现元素相关生物过程的分子机制研究;与相关分离方法联用,原子光谱和元素质谱还可以对生物组织中元素进行形态分析,研究其在相关过程中的生物转化过程。本文从单细胞元素分析、元素标签标记策略、金属药物转运与代谢以及生物组织中元素分布分析等方面,评述了原子光谱和ICP-MS在生命分析中的应用实例,并对该领域的发展前景进行了展望。     

Determination of Elements by Atomic Absorption Spectrometry in Medicinal Plants Employed to Alleviate Common Cold Symptoms

Eleven important medicinal plants generally used by the people of Turkey for the treatment of common cold have been studied for their mineral contents.Eleven minor and major elements(essential,non-essential and toxic)were identified in the Asplenium adiantum-nigrum L.,Althaea officinalis L.,Verbascum phlomoides L.,Euphorbia chamaesyce L.,Zizyphus jujube Miller,Peganum harmala L.,Arum dioscoridis Sm.,Sambucus nigra L.,Piper longum L.,Tussilago farfara L.and Elettaria cardamomum Maton by employing flame atomic absorption and emission spectrometry and electro-thermal atomic absorption spectrometry.Microwave digestion procedure for total concentration was applied under optimized conditions for dissolution of medicinal plants.Plant based biological certified reference materials(CRMs)served as standards for quantification.These elements are found to be present in varying concentrations in the studied plants.The baseline data presented in this work can be used in understanding the role of essential,non-essential and toxic elements in nutritive,preventive and therapeutic properties of medicinal plants.     

青海不同地区枸杞微量元素分析研究

为了对比青海不同地区枸杞的品质,采用ICP-MS和ICP-AES法对青海省12个产地的枸杞果实中11种微量元素含量进行了测定,并选取人体必需的7种微量元素,结合SPSS统计软件进行主成分分析。结果获得了3个主成分方程,并建立了主成分对变量的回归方程,对比较青海不同地区枸杞优劣以及获得高品质枸杞具有重要意义,为青海枸杞的开发和利用提供了科学依据。     

Determination of Pb,Zr, Ti,Sr, Cr,Nb and La in lead zirconate titanate ceramics by particle‐induced X‐ray emission

A particle‐induced X‐ray emission (PIXE) technique has been used in the determination of the principal components Pb, Zr and Ti and the substituting elements Sr, Cr, Nb and La in lead zirconate titanate ceramics. In general, precision of analysis was concentration dependent from each element under study. For Pb, precision varied between 0.13% and 0.16%, at higher concentration of 59.32–64.5%. It was around 6–9% for Sr, Cr and Nb at concentrations of 1% or lower. Particular attention was devoted to the estimation of the analysis trueness. With this purpose, three methods were applied: (1) comparison of PIXE and inductively coupled plasma optical emission spectrometry concentrations, (2) recovery study and (3) comparison with a laboratory standard. Trueness of analysis was around 100 ± 10% for the evaluated elements Pb, Zr, Ti, Sr and Cr. The expected stoichiometry and elemental composition homogeneity of a wide group of produced ceramics were confirmed by the PIXE technique. Copyright © 2012 John Wiley & Sons, Ltd.     

耀州古瓷釉层呈色机理的质谱研究方法

采用实验室自制飞秒激光电离飞行时间质谱(fs-LI-TOFMS)对唐代、五代、宋代、金代以及明代等五个朝代的耀州窑古瓷片釉层进行多元素同时分析,研究其呈色机理,以过渡元素为重点考察陶瓷釉层中所有可能着色元素的着色效果。推测耀州黑瓷烧制采用的很可能是Co-Cr-Fe-Mn系黑色釉料;明代白釉形成的主要原因是Fe元素含量低,还有可能与Ni元素有关;釉层中P 元素含量增多会导致釉色偏黄。毫无疑问,这一系列发现是对整个耀州瓷体系釉层呈色机理的重要补充。     

Mass Spectrometric Methods for Colorative Mechanism Analysis of Yaozhou Porcelain GlazeSCIEI北大核心CSCD

An in-house-built femtosecond laser ionization time-of-flight mass spectrometry (fs-LI-TOFMS) has been applied to the multi-elemental analysis of porcelain glaze from Yaozhou kiln. The samples are selected representing products of different dynasties, including Tang, Five, Song, Jin, and Ming Dynasty. For exploring the colorative mechanism of Yaozhou porcelain through the elemental analysis of the glaze, the effects of all potential coloring elements, especially transition elements, were considered. There was a speculation that the typical Co-Cr-Fe-Mn recipe was used in the fabrication of Yaozhou black glaze; the low content of Fe and high content of Ni resulted in the porcelain of white glaze; an increase content of P could lead the porcelain to be yellow-glazed. Undoubtedly, this research is an important supplement to the study of the colorative mechanism of the Yaozhou porcelain system.     

Use of EDXRF elemental fingerprinting for discrimination of botanical and geographical origin of Slovenian bee pollen

Bee pollen contains proteins, amino acids, carbohydrates, fats, fatty acids, vitamins, polyphenols, and mineral nutrients that make it useful as a good nutritional supplement in the human diet. It has the richest elemental composition among bee products which is not uniform and consequently varies greatly depending on botanical and geographical origin. In polyfloral and selected monofloral bee pollen samples: sweet chestnut, maple, dandelion, rapeseed, flowering ash, buckwheat, common ivy, and plantain, the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn, Br, Rb, and Sr were determined. A non-destructive energy dispersive X-ray fluorescence spectrometry was used for elemental fingerprinting. The most abundant elements in Slovenian bee pollen are K, P, S, Ca, and Cl followed by Fe, Mn, Zn, Rb, Br, and Sr. Several statistically significant differences in the content of analysed elements were found between studied groups according to the botanical and geographical origin which can be related to soil and plant elemental composition and plant metabolism. The obtained data extend our previous chemical profiling of Slovenian bee pollen and contribute to a more precise evaluation of some essential mineral nutrients in bee pollen to cover recommended dietary allowances in human nutrition. Additionally, this work contributes to a better understanding of mineral nutrient requirements in honey bee nutrition and of the environmental and agricultural impact of this product.     

微波溶样ICP-AES法测定甘肃东紫苏中的无机元素

将正交试验和方差分析应用于微波溶样ICP-AES法测定东紫苏地上部分K, Na, Ca, Ba, Pb, Zn, Mn, Cu, Mg, Fe和Al等无机元素的分析中,此方法简单、快速、灵敏度高、准确性好,且多种元素可同时测定,该方法的加标回收率为93.2%～104.1%, RSD(n=5)＜3.20%。结果表明: 东紫苏中含有丰富的对人体有益的微量元素,此结果可为探讨东紫苏中元素含量与其药效的相关性提供理论依据。     

Chaotic behavior in quantum optics and the failure of the Rotating-Wave Approximation at high intensities

We consider the semiclassical theory of a collection of two level atoms interacting with a single mode electric field. In this model the in quantum optics usually applied RWA fails at high field intensities. It is shown that the theory without applying the RWA can lead to a chaotic behavior, which can be described by a parametrically forced pendulum equation. The dynamics become more and more complicated if the electric field is increased. For extremely high intensities we obtain again a regular behavior described by a pendulum equation with a modified potential. In this case the dynamics is greatly different from the results obtained within RWA.     

Characterizing pseudoperiodic time series through the complex network approach

Recently a new framework has been proposed to explore the dynamics of pseudoperiodic time series by constructing a complex network [J. Zhang, M. Small, Phys. Rev. Lett. 96 (2006) 238701]. Essentially, this is a transformation from the time domain to the network domain, which allows for the dynamics of the time series to be studied via organization of the network. In this paper, we focus on the deterministic chaotic Rössler time series and stochastic noisy periodic data that yield substantially different structures of networks. In particular, we test an extensive range of network topology statistics, which have not been discussed in previous work, but which are capable of providing a comprehensive statistical characterization of the dynamics from different angles. Our goal is to find out how they reflect and quantify different aspects of specific dynamics, and how they can be used to distinguish different dynamical regimes. For example, we find that the joint degree distribution appears to fundamentally characterize spatial organizations of cycles in phase space, and this is quantified via an assortativity coefficient. We applied network statistics to electrocardiograms of a healthy individual and an arrythmia patient. Such time series are typically pseudoperiodic, but are noisy and nonstationary and degrade traditional phase-space based methods. These time series are, however, better differentiated by our network-based statistics.     

ICP-MS用于新疆紫草的无机元素初级形态分析及其溶出特性研究

应用电感耦合等离子体质谱技术(ICP-MS),分析了新疆紫草中20多种无机元素的初级形态;并研究了不同提取溶剂对其溶出特性的影响。结果显示：在消解方法上,高温密封消解较之微波辅助消解(MAP)能更彻底地消解样品,达到分析要求;在溶液中,除了K,Zn以溶解态为主要存在形式外,其余绝大部分元素主要以悬浮态存在;不同提取溶剂的极性与所分析的无机元素密切相关。Mg,K,Ca,Mn,Tl, Co和Pb等7种元素的提取得率与其提取溶剂极性呈完全的正比例关系,其余元素尽管略有差异,但基本上呈线性关系。     

A Review of Selenium (Se) Nanoparticles: From Synthesis to Applications

Selenium is an essential trace element that plays a crucial role in various physiological activities, exerting a significant impact on human health. Selenium deficiency can lead to the development of several diseases, while excessive doses can be toxic. In recent years, there is a growing interest in elemental selenium nanoparticles (SeNPs) due to their good biocompatibility, low toxicity, and high antioxidant activity, making them suitable for numerous applications. The quest for enhancing efficacy and reducing toxicity has driven extensive research on SeNPs. This review aims to provide a comprehensive summary of the recent advancements made in the synthesis, characterization, properties, and applications of SeNPs. Moreover, the challenges associated with SeNPs research, as well as the future trends in the field, are thoroughly discussed. This review aims to provide an insight into the current state of research on SeNPs and highlight areas that require further exploration and development.     

Risk assessment and laser safety

The basic tenets of risk assessment have always been applied in laser safety during the development of safety standards. For example, statistical methods were used in the probit analysis of the threshold of ocular injury; concepts of risk analysis were employed in the development of hazard classes, where the increased risk of exposure and potential for injury from increasing laser output power led to assignment of an increasing hazard class. In recent years, however, there has been a number of attempts to apply statistical probability analysis in the risk assessment of actual use conditions. However, once the hazard classification has been assigned, how should one further apply the techniques of risk assessment in the determination of hazard control measures, or does this lead to a potential controversy of what is the risk? Risk analysis is the evaluation of potentially hazardous exposure conditions coupled with a realistic assessment of actual human exposure. The maximum permissible exposure values for laser radiation coupled with the laser hazards classification scheme, already permit realistic health hazard evaluations. However, in determining effective hazard control measures, one must perform a risk analysis. A risk analysis must consider aspects of human behaviour and how behaviour affects exposure. This is frequently the area of greatest controversy in the derivation of safety standards; however, it is this aspect where standards are most needed.     

西洋参中无机元素的主成分分析和聚类分析

采用电感耦合等离子体质谱(ICP/MS)法测定了12个西洋参样品中18种无机元素的含量,建立西洋参无机元素指纹谱,并用SPSS主成分分析法对西洋参中的特征元素进行分析;主成分分析选出五个主因子,得出西洋参的特征元素为Fe,Al,V,Mn,Mg,Sr,Mo,Ca,Cu;聚类分析将12个西洋参样品聚成五大类,表明元素的分布特征与西洋参的品种关系显著;主成分分析法和聚类分析法是西洋参无机元素分析的有效方法.     

Finite‐element modelling of multilayer X‐ray optics

Multilayer optical elements for hard X‐rays are an attractive alternative to crystals whenever high photon flux and moderate energy resolution are required. Prediction of the temperature, strain and stress distribution in the multilayer optics is essential in designing the cooling scheme and optimizing geometrical parameters for multilayer optics. The finite‐element analysis (FEA) model of the multilayer optics is a well established tool for doing so. Multilayers used in X‐ray optics typically consist of hundreds of periods of two types of materials. The thickness of one period is a few nanometers. Most multilayers are coated on silicon substrates of typical size 60 mm × 60 mm × 100–300 mm. The high aspect ratio between the size of the optics and the thickness of the multilayer (10⁷) can lead to a huge number of elements for the finite‐element model. For instance, meshing by the size of the layers will require more than 10¹⁶ elements, which is an impossible task for present‐day computers. Conversely, meshing by the size of the substrate will produce a too high element shape ratio (element geometry width/height > 10⁶), which causes low solution accuracy; and the number of elements is still very large (10⁶). In this work, by use of ANSYS layer‐functioned elements, a thermal‐structural FEA model has been implemented for multilayer X‐ray optics. The possible number of layers that can be computed by presently available computers is increased considerably.     

利用激光诱导击穿光谱原位在线检测褐煤及煤烟

褐煤是我国现阶段的主要用煤,但因为其较低的煤化程度,使用时会产生污染环境的二氧化碳和黑灰,而且烟尘中含有的金属离子会危害人体健康,所以开展对褐煤烟尘的研究非常有意义.而激光诱导击穿光谱技术(L IBS)具有快速、多元素同时分析的特点,适合用于煤烟的原位在线探测.实验制备了含铅浓度不同的三种褐煤样本(O,H,L),其中O...     

Correlations between Raman parameters and elemental composition in lead and lead alkali silicate glasses

This article examines the influence of the composition on the Raman spectra of lead silicate glass. Modern and historic lead alkali glasses and high‐lead glazed ceramics were analysed complementarily by Raman spectrometry and elemental techniques, either electron microprobe, proton induced X‐ray emission (PIXE) or scanning electron microscope with energy dispersive spectrometry (SEM‐EDS). The results showed that lead alkali silicate and high‐lead silicate glasses can be easily distinguished from their Raman spectra profile. In lead alkali silicate glasses, continuous variations were observed in the spectra with the compositional change. In particular, the position of the intense peak around 1070 cm⁻¹ was linearly correlated to the lead content in the glass. A unique decomposition model was developed for the spectra of lead alkali silicate glasses. From the combination of the Raman and elemental analyses, correlations were established between the spectral components and the composition. These correlations permitted to interpret the spectra and access additional compositional information, such as the lead content from area ratio A₉₉₀/A_900–1150, the total alkali + alkaline‐earth content from the area ratio A₁₁₀₀/A_900–1150 or the silica content from the area ratio A₁₁₅₀/A_900–1150. In lead silicate glass containing over 25 mol% PbO, the compositional variation induced no variation in the SiO₄ network region of the Raman spectra [150–1350 cm⁻¹], therefore no correlations and compositional information could be gained from the glass spectra in this range of composition. This new development of Raman spectroscopy for the analyses of glass will be very valuable for museums to not only access compositional information non‐destructively but also to understand the structural changes involved with their alteration. Copyright © 2008 John Wiley & Sons, Ltd.     

Minimum detection time (MDT) for elemental EDXRF images

When obtaining a chemical element image through energy dispersive X‐ray fluorescence (EDXRF) scanning of a specific sample, it is important to determine the minimum detection time (MDT) required per dot (pixel) and per element in order to identify the minority and the trace elements present in the sample. Starting from the statistical criteria of limit of detection, quantitative estimations can be made regarding the concentration of elements present in the samples, determining the MDT which fits to the limit of detection previously established. Given that with this technique it is possible to implement in vivo applications, in this work, a process was developed for the MDT that is capable of generating the minimum radiation exposure in imaging EDXRF. For this proposal, the MDT is determined for metals, such as Fe, Cu, and Pb, given their great biomedical interest, in a series of equivalent bone and soft tissue phantom samples. Consequently, a criteria for global scanning time per dot was established, hence providing an elemental XRF image according to the As Low As Reasonably Achievable principles, i.e. as low an exposure as reasonably possible for each sample type studied by this sort of devices, in order to obtain appropriate information for each field of application. Copyright © 2015 John Wiley & Sons, Ltd.     

Spatio-temporal dynamics of security investments in an interdependent risk environment

In a globalised world where risks spread through contagion, the decision of an entity to invest in securing its premises from stochastic risks no longer depends solely on its own actions but also on the actions of other interacting entities in the system. This phenomenon is commonly seen in many domains including airline, logistics and computer security and is referred to as Interdependent Security (IDS). An IDS game models this decision problem from a game-theoretic perspective and deals with the behavioural dynamics of risk-reduction investments in such settings. This paper enhances this model and investigates the spatio-temporal aspects of the IDS games. The spatio-temporal dynamics are studied using simple replicator dynamics on a variety of network structures and for various security cost tradeoffs that lead to different Nash equilibria in an IDS game. The simulation results show that the neighbourhood configuration has a greater effect on the IDS game dynamics than network structure. An in-depth empirical analysis of game dynamics is carried out on regular graphs, which leads to the articulation of necessary and sufficient conditions for dominance in IDS games under spatial constraints.