中国X射线荧光光谱分析的进展

作者于1979年与1982年对中国X射线荧光光谱分析的概况与进展进行过综述,并分析当时X荧光光谱分析所存在的问题,提出了建议,现结合近几年中国X射线荧光光谱分析工作者在国内外杂志上所发表的多数文章进行综述,其中包括近几年来我国X射线荧光光谱分析书刊专著的编写与出版,X射线荧光光谱分析仪器的研制与X射线荧光光谱分析的应用,特别是在X射线荧光光谱分析的应用方面,近几年进展较快,应用电子计算机校正元素间的吸收—增强效应的工作,不但吸收了国外的一些经验。应用到实际工作中去,而且对一些模式的应用提出了改进或提出不同的模式。在制样技术方面结合我国的实际情况做了某些改进,在冶金,地质,环保,建材,石油,化工,机械,文教,科研等部门,结合工作中的需要提出了不少切实可行的报告。文章中引用的文献约八十篇左右。     

X射线荧光在地质材料卤族元素分析中的应用评介

卤族元素氟、氯、溴、碘广泛分布在地圈、水圈和生物圈,它们是矿产资源,也是许多地学研究的信息载体,更与人类生活紧密相关.卤族元素分析是地质分析的重要组成部分,而X射线荧光光谱分析方法在当今的卤族元素分析中占有重要地位.本文收集我国1988年—2020年间X射线荧光光谱分析地质材料氟、氯、溴、碘的文献126篇,在简述卤族元...     

全国第六届X射线荧光光谱学术报告会征文通知（第一轮通知）

为了促进我国X射线荧光光谱 (包括波长色散、能量色散、全反射、微区、粒子激发的X荧光等 )分析工作者的国内和国际交流 ,展示我国在该领域研究和应用的最新进展 ,决定于 2 0 0 5年 10月在江西九江召开全国第六届X射线荧光光谱学术报告会 ,会期 4天。会议由中国地质学会、中国光学学会和中国硅酸盐学会主办 ,中国科学院上海硅酸盐研究所和上海市硅酸盐学会承办。会议期间 ,拟邀请国内外著名X射线荧光光谱分析专家 (如X RAYSPECTROMETRY杂志主编VANGRIEKEN教授、副主编KAWAI教授、副主编罗立强教授、制样专家CLAISSE教授、…     

第35届X射线会议

第35届X射线会议于1986年8月4日至8日的美国Denver大学召开,有各国代表335人参加,收到X射线荧光光谱分析方面的文章49篇,X射线衍射分析方面的文章42篇,另有28家X射线分析仪器厂家参加展出。会议报告将刊登在“X射线进展”一书中。     

第三届全国X射线荧光光谱分析学术报告会在黄山市召开

由中国地质学会和中国光谱学会共同举办的第三届全国XRFA学术报告会于1988年10月17日至22日在安徽黄山市举行。会议收到论文69篇,大会交流的论文共有52篇。到会代表共86人。会议分大会报告和分组报告进行,论文的质量从深度和广度方面都有所进展,水平有所提高。大会报告反映了近两年来我国X射线荧光光谱分析的进展;概况地介绍了第37届丹佛     

X射线能谱分析

1895年发现了X射线.1923年前后莫斯莱(Mo-sely)对X射线特征谱和原子序数之间的关系作了系统整理,得到了莫斯莱定律;随后布喇格(Bragg)发表了X射线衍射定律.X射线光谱分析的基础就这样奠定了.1923年丹麦物理工作者在X射线光谱中成功地把给(Hf)从化学、物理性能十分相似的锆中区别出来,证实了第72号元素的存在;以此为开端,作为成份分析的手段,X射线分析就因其非破坏性、快速、准确、操作简单等长处,在材料鉴定、生产过程质量控制中应用开了. 但是X射线光谱分析真正的繁荣是四十年代以后的事,这是因为终于制造出了稳定的X射线激发源、加工…     

上海光谱学会举行1990年年会

上海光谱学会于1990年11月30日举行年会。会议共收到原子光谱分析、分子光谱分析、X荧光光谱分析、激光光谱、光谱仪器等方面的论文和综述共29篇,包括来自苏州的稿件,其中有些作者是青年光谱工作者。出席年会的有老专家和青年学者九十余人,会议在热烈的学术气氛中进行了讨论和交流。     

第四届《光谱分析学术讨论会》会议纪要

由《光谱实验室》编辑部和广西光学学会联合举办的《第四届光谱分析学术讨论会》于1990年11月7日至11日在桂林市召开。到会代表178名,其中具有高、中级技术职称的约占总人数的87%,除个别年长者和青年人外,绝大多数是中年科技工作者。代表们来自全国二十八个省市自治区的大专院校、科研单位、工矿企业和卫生商检部门。参加这届会议的人数之多、代表面之广都是空前的,因此,这是光谱分析界的一次盛会。会议收到论文105篇,其中发射光谱(主要是ICP-AES)42篇,原子吸收光谱方面的32篇,分光光度方面的14篇,红外光谱方面的10篇,X射线荧光分析方面的6篇。为了在有限的时间内使所有论文都能得到交流和讨论的机会,会议领导小组选出五篇论文作为大会报告,其余的分别在四个专业小组会上进行交流。     

氧化铝的X射线荧光光谱分析方法研讨

简要论述了氧化铝的X射线荧光光谱分析方法原理、样品处理、设备特点;在德国布鲁克公司的S4型X射线荧光光谱仪上用融片法分析氧化铝中的杂质含量,重点论述了用X射线荧光光谱法代替传统的化学分析方法的优势和不足.     

X射线管激发X荧光光谱连续本底扣除方法研究

X射线管是目前X射线荧光光谱分析中最常采用的激发源,它所产生的原级谱成为了X荧光光谱中本底成分的主要来源,在对这种光谱进行进一步的分析处理之前需要对其本底进行扣除,对本底估计的准确性直接影响后续处理步骤的效果。对射线管激发X荧光光谱的成分进行了分析,针对其本底特点构造了一种本底强度的估计方法,并根据实测谱线构建了理论测试谱线以便对光谱处理算法的效果进行评价。该方法利用测得X射线荧光光谱中不包含特征峰的谱段对X射线管原级谱造成的本底成分进行估计,使用只包含连续本底的谱段对整个测量谱段进行插值,从而避免了谱线特征峰重叠或对半高宽估计不当时所产生的影响。利用构建的测试光谱对SNIP法、傅里叶变换法和本文的本底估计方法的使用效果进行了比较,使用该方法估计的本底与理论本底更加接近。结果表明使用的方法对X射线管激发的X荧光光谱的本底估计准确,可以采用这种方法对连续本底进行扣除,在对实际测得的X射线荧光光谱的本底扣除中取得了较好的应用效果。     

Universality in bibliometrics

Many discussions have enlarged the literature in Bibliometrics since the Hirsch proposal, the so called h-index. Ranking papers according to their citations, this index quantifies a researcher only by its greatest possible number of papers that are cited at least h times. A closed formula for h-index distribution that can be applied for distinct databases is not yet known. In fact, to obtain such distribution, the knowledge of citation distribution of the authors and its specificities are required. Instead of dealing with researchers randomly chosen, here we address different groups based on distinct databases. The first group is composed of physicists and biologists, with data extracted from Institute of Scientific Information (ISI). The second group is composed of computer scientists, in which data were extracted from Google-Scholar system. In this paper, we obtain a general formula for the h-index probability density function (pdf) for groups of authors by using generalized exponentials in the context of escort probability. Our analysis includes the use of several statistical methods to estimate the necessary parameters. Also an exhaustive comparison among the possible candidate distributions are used to describe the way the citations are distributed among authors. The h-index pdf should be used to classify groups of researchers from a quantitative point of view, which is meaningfully interesting to eliminate obscure qualitative methods.     

Bibliometric Mapping of Literature on High-Entropy/Multicomponent Alloys and Systematic Review of Emerging Applications

High-entropy/multicomponent alloy (HEA/MCA) has received significant research attention in the last decade. There is a dearth of data-driven works dedicated to assessing and visualizing the HEA/MCA literature from a global perspective. To this end, we present the first bibliometric literature analysis of more than 3500 HEA/MCA articles, published between 2004 and 2021, in the Scopus database. We identify the most prolific authors, their collaborators, institutions, and most prominent research outlet. Co-occurrence networks of keywords are mapped and analyzed. A steep rise in research outputs is observed from 2013, when the number of annual publications doubled the previous years. The top five preferred research outlets include Journal of Alloys and Compounds, Materials Science and Engineering A, Scripta Materialia, Intermetallics, and Acta Materialia. Most of these publications emanate from researchers and institutions within China, USA, and Germany, although international scientific collaboration among them is lacking. Research gaps and future research directions are proposed, based on co-occurrence frequencies of author keywords. Finally, a brief systematic review of emerging applications, covering hydrogen storage, additive manufacturing, catalysis, and superconductivity, is undertaken. This work provides an important comprehensive reference guide for researchers to deepen their knowledge of the field and pursue new research directions.     

A Review of Application of Total Reflection X-ray Fluorescence Spectrometry to Water Analysis

Abstract

The aim of this article is to review the literature on the application of the total reflection X-ray fluorescence (TXRF) spectrometry for the determination of the chemical composition of aqueous samples. Details of the main stages of the analytical procedures are described. Special attention is given to the sample preparation procedure, current instrumentation, and potential error sources when analyzing the water samples of varying compositions. The examples of matrix effects and spectral interferences as well as the analytical figures of merit are also presented.     

同步辐射X射线荧光光谱国内外研究进展

同步辐射光源是带电粒子在加速器储存环中以接近光速的速度运动时,沿轨道切线方向发射出的辐射,同步辐射X射线荧光分析(SR-XRF)是以同步辐射X射线作为激发光源的X荧光光谱分析技术.同步辐射X射线荧光分析包括了用于微区及微量元素分析的同步辐射XRF、用于表面及薄膜分析的同步辐射全反射X射线荧光(SR-TXRF)以及用于三...     

The influence of relaxation and nondipole effects on the intensity of X-ray photoelectron spectra

The photoionization cross sections; dipole and nondipole parameters of the angular distribution of photoelectrons; and the spectroscopic factors for the main X-ray photoelectron lines, which are used in quantitative analysis of the surface and most of atoms, have been calculated. It is shown that consideration of nondipole effects leads to a significant (up to 10%) change in the photoelectron angular distribution. Therefore, neglect of nondipole transitions may lead to an error above 10% when MgK _α and AlK _α X-ray lines are used for surface analysis. Consideration of the spectroscopic factors leads to a decrease in the absolute line intensity by about 20%. Calculations showed that this value weakly depends on the atomic number and quantum shell numbers.     

Electronic structure and optical properties of RbPb2Br5

We report on density functional theory (DFT) calculations of the total and partial densities of states of rubidium dilead pentabromide, RbPb₂Br₅, employing the augmented plane wave+local orbitals (APW+lo) method as incorporated in the WIEN2k package. The calculations indicate that the Pb 6s and Br 4p states are the dominant contributors to the valence band: their main contributions are found to occur at the bottom and at the top of the band, respectively. Our calculations reveal that the bottom of the conduction band is formed predominantly from contributions of the unoccupied Pb 6p states. Data of total DOS derived in the present DFT calculations are found to be in agreement with the experimental X-ray photoelectron valence-band spectrum of this compound. The predominant contributions of the Br 4p states at the top of the valence band of rubidium dilead pentabromide are confirmed by comparison on a common energy scale of the X-ray emission band representing the energy distribution of the valence Br p states and the X-ray photoelectron valence-band spectrum of the RbPb₂Br₅ single crystal. Main optical characteristics of RbPb₂Br₅, such as dispersion of the absorption coefficient, real and imaginary parts of dielectric function, electron energy-loss spectrum, refractive index, extinction coefficient and optical reflectivity are explored for RbPb₂Br₅ by the DFT calculations.     

Republication of: Exact solutions of the field equations of the general theory of relativity

This is an English translation of a paper by Pascual Jordan, Jürgen Ehlers and Wolfgang Kundt, first published in 1960. The original paper was part 1 of a five-part series of articles containing the first summary of knowledge about exact solutions of Einstein’s equations found until then. (The other parts of the series will be printed as Golden Oldies in the future.) The paper has been selected by the Editors of General Relativity and Gravitation for re-publication in the Golden Oldies series of the journal. It is accompanied by an editorial note written by G. F. R. Ellis, and by the biographies of the authors: P. Jordan (written by A. Krasiński) and W. Kundt (written by himself). The biography of J. Ehlers is contained elsewhere in the same issue of GRG, which is devoted to his memory. An editorial note to this paper and a biography can be found in this issue preceding this Golden Oldie and online via doi:. Original paper: Pascual Jordan, Jürgen Ehlers, Wolfgang Kundt, Strenge L?sungen der Feldgleichungen der Allgemeinen Relativit?tstheorie. Akademie der Wissenschaften und der Literatur, Abhandlungen der Mathematisch-naturwissenschaftliche Klasse Nr 2S (1960), pp. 21–105. Reprinted with the kind permission of the Academy of Sciences and Literature, Mainz, and of the authors: Jürgen Ehlers and Wolfgang Kundt. Translated by Anita Ehlers, Anita.Ehlers@t-online.de, and by Manfred Trümper, manfred@truemper.fr, with ample help from Wolfgang Kundt. P. Jordan (Deceased July 31, 1980) J. Ehlers (Deceased May 20, 2008)

---

华南沿海末次冰期类黄土沉积的漫反射光谱与激光粒度研究

野外调查发现,华南沿海广泛发育一套黄色粉土沉积。为研究其特征属性及成因,选择具有代表性的3条粉土剖面及1个钻孔采样,使用漫反射光谱（DRS）分析和激光粒度（LPS）分析的方法,率先尝试从沉积物铁矿物的产出形式和沉积物粒度配分特征的角度,综合判定沉积物的沉积环境、搬运营力及成因机制。DRS分析结果表明,在黄色粉土的漫反射光谱一阶导数曲线中,铁矿物的特征峰峰高总体有赤铁矿（565 nm）>针铁矿(505和435 nm）的变化特征,与我国北方风成黄土的漫反射光谱一阶导数曲线形态吻合,均体现的是相对干冷的气候环境;而区内的河、海相沉积物曲线所反映的铁矿物特征峰的峰高变化与上述黄色粉土的变化方向相反,表明样品经历过充分的水化作用并长期处于潮湿的还原环境之中。LPS分析结果表明：各剖面（钻孔）黄色粉土的粒度组成均较为均一,粒组配分模式具显著的双峰式,两个峰值分别为主峰10～50 μm 区段和次峰<5 μm区段,与黄土沉积的粒度配分模式一致,是风成沉积的特征粒组构成;而与区内河、海相沉积物粒组呈单向变化的配分模式有显著差异。结合黄色粉土的年龄介于10～80 ka之间,以及正负地形皆广泛存在的空间分布特征,最终认为该套沉积是形成于末次冰期的风成沉积（本研究称“类黄土”）。     

Estimating size and scatter of world physics journal literature

Conclusions The foregoing analysis assumes the whole of physics journal literature to follow a Bradford distribution. However, figure 1, as well as other published Bradford plots of physics literature, show similar Groos droop deviations from linearity at the upper end [13, 14]. The common explanation for this deviation is incompleteness of the bibliographic data [5], but this of course cannot be proven without compiling a truly complete world bibliography on the subject. If the droop is real, i.e. not the consequence of bibliographic incompleteness, then the estimates of journals and papers are exaggerated. On the other hand, another assumption is that the first 110 ranked journals in this study are indeed the top producing physics journals, and that all source items published in these journals are actually physics papers. The extent to which this assumption does not hold means a decrease in the estimates, thereby opposing the first possible error. The fact that the actual number of papers published by the journal of first rank exceeds B, the theoretical number derived from analysis, suggests an underestimate of total journals and papers. This supports the assumption that any deviation from the Bradford distribution is minimal and that the Groos droop is a consequence of bibliographic incompleteness.It cannot be assumed that the highest quality literature is concentrated in the higher Bradford ranks. There may be a relationship between quality and scatter, as earlier work has suggested [9], but this is a matter for further investigation. It is clear that frequency-rank distributions such as Bradford's Law have more potential for scientific information management than has been so far exploited.     

Technical structure of the global nanoscience and nanotechnology literature

Text mining was used to extract technical intelligence from the open source global nanotechnology and nanoscience research literature. An extensive nanotechnology/nanoscience-focused query was applied to the Science Citation Index/Social Science Citation Index (SCI/SSCI) databases. The nanotechnology/nanoscience research literature technical structure (taxonomy) was obtained using computational linguistics/document clustering and factor analysis. The infrastructure (prolific authors, key journals/institutions/countries, most cited authors/journals/documents) for each of the clusters generated by the document clustering algorithm was obtained using bibliometrics. Another novel addition was the use of phrase auto-correlation maps to show technical thrust areas based on phrase co-occurrence in Abstracts, and the use of phrase–phrase cross-correlation maps to show technical thrust areas based on phrase relations due to the sharing of common co-occurring phrases. The ∼400 most cited nanotechnology papers since 1991 were grouped, and their characteristics generated. Whereas the main analysis provided technical thrusts of all nanotechnology papers retrieved, analysis of the most cited papers allowed their characteristics to be displayed. Finally, most cited papers from selected time periods were extracted, along with all publications from those time periods, and the institutions and countries were compared based on their representation in the most cited documents list relative to their representation in the most publications list.