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1.
文摘是以提供文献内容梗概为目的、不加评论和补充解释,简要明确地记叙文献重要内容的独立短文。其基本要素包括研究的目的、方法、结果、结论,具有独立性和自明性。①目的——研究、研制、调查等的前提、目的和任务所涉及的主题范围。②方法——所用的原理、理论、条件、对象、材料、工艺、结构、手段、装备、程序等。③结果——实验的、研究的结果、数据,被确定的关系,观察结果,得到的效果,性能等。④结论——结果的分析、研究、比较、评价、应用,提出的问题,今后的课题,假设,启发,建议,预测等。  相似文献   

2.
《分析测试学报》是由中国广州分析测试中心、中国分析测试协会共同主办的全国性学术刊物,中文核心期刊。刊登质谱学、光谱学、色谱学、波谱学、电化学、电子显微学等方面的分析测试新理论、新方法、新技术的研究成果,介绍新仪器装置及在生物、医药、化学化工、商检、食品检验等方面实用性强的实验技术。适合科研院所、高等院校、检测机构、医药、卫生以及厂矿企业分析测试工作和管理人员阅读。  相似文献   

3.
1978年9月初在长春召开了国家科委光学及应用光学学科组会议,到会的国内知名科学家有钱临照、王大珩、苏韦、陈杏蒲、高兆兰、洪晶、张志三、胡南琦、唐九华、于家本、梅遂生、林钧挺、贾循德、吴国安、王之江、邓锡铭、干福熹、匡定波、林祥棣、龚知本、刘树杞、马林、李小琼等,王大珩是学科组组长,我是学科组秘书.在这次会议上提出了成...  相似文献   

4.
ICP-AES测定多目标水地球化学普查样品中的14种微量元素   总被引:3,自引:0,他引:3  
采用IRIS Intrepid Ⅱ SXP ICP光谱仪,对地球化学普查水样中Ba、Be、Cd、Co、Cr、Cu、Fe、Mn、Mo、Ni、P、Pb、Sr和Zn等元素的测量条件进行了探讨,优化了实验条件,进行了大批量实际样品的测定.方法简便,快速.检出限、精密度和准确度均符合质量管理的要求.  相似文献   

5.
<正>《光散射学报》是中国物理学会光散射专业委员会、四川省物理学会和四川大学联合主办的专业性学术刊物,宗旨是交流光散射(拉曼散射、布里渊散射、瑞利散射)、光物理、光化学、光牛物等学科在理论、实验、实验技术和仪器方面的研究成果,以及它们在物理、化学、材料科学、生物学、地矿学、石油化工、医药学等方面的应用成果,为科学发展和技术进步提供讨论、交流场所。1.开设栏目  相似文献   

6.
1征稿范围本刊征集反映国内外光学、光电子学、光学技术应用的最新科学理论、研究成果、前沿技术和发展动态的原创性论文、技术报告、阶段性研究报告和综合评述等。2稿件要求来稿应信息准确、论点鲜明、实验数据可靠、条理清晰、文字精  相似文献   

7.
正《发光学报》是中国物理学会发光分会、中国科学院长春光学精密机械与物理研究所主办的,以发光学、凝聚态物质中的激发态过程为专业方向的综合性学术刊物。本刊适用于凝聚态物理、光学材料合成、环境保护、化学化工、国防、医药等领域的科学研究单位、高等院校、制造厂家、从事发光学与光学材料开发的研究人员、高校有关专业的师生等。刊登的主要学术内容包括:1.无机、有机和生物材料的光致发光、电致发光和阴极射线发光及其应用;  相似文献   

8.
《发光学报》2012,(1):116
《发光学报》是中国物理学会发光分会、中国科学院长春光学精密机械与物理研究所主办的,以发光学、凝聚态物质中的激发态过程为专业方向的综合性学术刊物。本刊适用于凝聚态物理、光学材料合成、环境保护、化学化工、国防、医药等领域的科学研究单位、高等院校、制造厂家、从事发光学与光学材料开发的研究人员、高校有关专业的师生等。刊登的主要学术内容包括:  相似文献   

9.
《发光学报》2012,(3):350
《发光学报》是中国物理学会发光分会、中国科学院长春光学精密机械与物理研究所主办的,以发光学、凝聚态物质中的激发态过程为专业方向的综合性学术刊物。本刊适用于凝聚态物理、光学材料合成、环境保护、化学化工、国防、医药等领域的科学研究单位、高等院校、制造厂家、从事发光学与光学材料开发的研究人员、高校有关专业的师生等。刊登的主要学术内容包括:  相似文献   

10.
为保证食品安全和消费者健康,无损检测技术广泛应用于果蔬质量检测中。光谱和图像技术可分别获取果蔬的内部和外部信息,成为质量检测的有效工具。为跟踪国内外研究进展并分析研究现况,从果蔬外部品质(尺寸、形状、表面缺陷、颜色、纹理等)、内部品质(内部缺陷、可溶性固形物、可滴定酸、水分、类胡萝卜素等单一品质及综合品质)、成熟度、货架期/贮藏期、产品溯源、生长监测、安全(农药残留、病虫和细菌侵染、转基因产品等)检测及光学系统设计等方面综述了光谱和成像技术的应用,分析了存在的图谱库不完善、解混处理算法复杂、高精度和便携式的光学系统开发力度不够、校正模型的影响因素复杂等问题。然后,归纳了发展趋势,指出了各组分可视化分析及交互作用机理解析、光与果蔬组织的交互作用机理分析和光学特性参数反演等光学特性分析、科学合理的综合评价体系的建立、新算法的应用和多种算法的联合使用、不同算法的可靠性和稳定性的提高、稳定和普适模型的建立、低成本和便携式等光学分析仪器的商品化开发和商业化应用等成为进一步探索的方向,为基于光谱和成像技术的果蔬质量检测发展提供了参考。  相似文献   

11.
A group of 83 coins, found in the archeological excavations of the ancient Roman city of Tridentum (Trento, Italy), was studied for the determination of their composition, finalized to their classification and cataloging. The coins, mainly made of copper‐based alloys, were minted between the republican period (II century BC) and the last decades of the western empire (V century AD). The X‐Ray Fluorescence archaeometric analysis has allowed a revision of the typological classification of the coins through the identification of six broad groups, each one characterized by a peculiar composition of the coins in the group. A tentative assignation of all the unreadable coins to one of the groups identified was proposed, in a way that could suggest also a possible dating of these coins. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

12.

For classical random walks, changing or not changing coins makes a trivial influence on the random-walk behaviors. In this paper, we investigate the quantum walk where a walker’s movement is controlled by two initially independent coins alternately partially or fully after each step. We observe that there exist complicated inter-coin correlations in the quantum walk. Specifically, we study the correlations of two coins by tracing out the walker, and analyze classical, general, and quantum correlations between two coins in terms of classical mutual information, quantum mutual information, and measurement-induced disturbance. Our analysis shows different quantum features from that in classical random walks.

  相似文献   

13.
Celtic gold coins found in Southern Germany were studied by Mössbauer spectroscopy, electron microprobe analysis and X-ray diffraction with special attention to coins rich in silver and copper. In such coins the electron microprobe analyses reveal a gold enrichment in a surface layer of more than 100 μm thickness. 197Au conversion electron Mössbauer spectroscopy also shows that the surface of the coins consists of two phases, one of which is strongly enriched in gold compared to the bulk composition. In comparison with laboratory experiments the observed phenomena suggest that coin production in Celtic times may have involved deliberate heating and etching steps to enrich the surface layer in gold by depleting it of silver and copper.  相似文献   

14.
《X射线光谱测定》2005,34(2):128-130
Punch‐marked coins are the oldest known numismatic objects used in ancient India. Seven punch‐marked silver coins were analysed by using the non‐destructive multi‐elemental PIXE technique. A 3 MeV proton beam from a pelletron accelerator was used for irradiation of these samples to obtain the spectral data and GUPIX software was employed to derive the elemental concentrations. The results reveals that silver, copper, gold and lead are significant constituents of the punch‐marked silver coins and there are also traces of elements such as Ti, Cr, Mn, Fe, Co, Ni, As and Y, which seems to imply that PIXE can be used effectively for the non‐destructive quantitative analysis of ancient coins. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

15.
Four hundred and sixteen silver coins stemming from the Ottoman Empire (16th and 17th centuries) were analyzed to confirm the fineness of the coinage as well as to study the provenance of the alloy used for the coins. As most of the coins showed the typical green patina on their surfaces due to corrosion processes that have led to the depletion of copper in the near surface domains of the silver coins in comparison to their core composition, small samples had to be taken, embedded in synthetic resin, and cross sectioned to investigate the true‐heart metal composition. μ‐synchrotron micro X‐ray fluorescence analysis and μ‐proton‐induced X‐ray emission were applied to determine the silver contents as well as the minor and trace elements. The type of the alloy was investigated as well as if coins minted in different locations demonstrated homogeneous traits concerning the predominant impurities (Au and Bi), which could suggest a common ore. Finally, energy‐dispersive microanalysis in a scanning electron microscope was applied to study the homogeneity/heterogeneity of the coins and the presence of surface enrichments and to explain differences between the μ‐synchrotron micro X‐ray fluorescence analysis and μ‐proton‐induced X‐ray emission measurements concerning the main component. In general, the silver content of the analyzed specimen varies between 90 and 95%. These outcomes have not supported the historical interpretations, which predict that during the period studied, a debasement of approximately 44% of the silver content of the coins should have occurred. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

16.
We propose a simple stochastic exchange game mimicking taxation and redistribution. There are g agents and n coins; taxation is modeled by randomly extracting some coins; then, these coins are redistributed to agents following Polya's scheme. The individual wealth equilibrium distribution for the resulting Markov chain is the multivariate symmetric Polya distribution. In the continuum limit, the wealth distribution converges to a Gamma distribution, whose form factor is just the initial redistribution weight. The relationship between this taxation-and-redistribution scheme and other simple conservative stochastic exchange games (such as the BDY game) is discussed.  相似文献   

17.
利用X射线衍射(XRD)、X射线荧光(XRF)等手段,对湖北鄂州博物馆馆藏的当地出土的几枚锈蚀较明显的清代黄铜钱币进行了检测分析,钱币本体含Zn量36.53%~37.75%,含Cu量54.12%~59.04%,含Pb量3.51%~7.56%,合金配比稳定科学,显示清朝中后期黄铜合金技术已经相当成熟。腐蚀产物中首次发现了绿铜锌矿(Zn3Cu2(OH)6(CO3)2),此外还有黑铜矿(CuO)、红锌矿(ZnO)、铜盐(CuCl)等,当地埋葬环境中较高的Cl-含量(包括环境的污染)可能是致使这批黄铜钱币腐蚀较严重的主要原由。为钱币的收藏和保护提供了一定的参考意义。  相似文献   

18.
By means of the combined use of surface and micro-analytical techniques the surface chemical composition of ancient coins and some aspects of their manufacturing techniques and of degradation mechanisms have been elucidated. Two case histories are described concerning silver Roman Republican coins and some coins plated with thin films of silver and gold. In particular, the coinage methods, the silvering and gilding techniques and the origin of the embrittlement of these selected Roman coins have been studied by means of the combined use of selected-area X-ray photoelectron spectroscopy (SA-XPS) and scanning electron microscopy and energy-dispersive spectrometry (SEM+EDS). This innovative approach has been utilised in order to gain further insight into the microchemical structure of the external regions of the coins as well as of the bulk features. The results show the use of mercury to coat a copper or silver core with a thin film of precious metals that could be considered the most important advance in the technology of gilding to be made in antiquity. Furthermore, the microchemical investigation of brittle Roman silver coins has allowed us to identify the origin of this troublesome problem. The microchemical results indicate that brittleness is induced by the presence of a low amount of lead that is retained in supersaturated solution when the cast blank was produced. This latter element segregates at the grain boundaries during the coin production and the subsequent long-term ageing at room temperature, thus inducing the alloy fracturing along the weakened grain boundaries. PACS 68.55.Jk; 68.35.Dv; 68.37.Hk; 68.55.Nq; 81.05.Bx  相似文献   

19.
In order to establish a new handling procedure for contaminated coins, the Coin Cabinet and the Conservation Science Department of the Kunsthistorisches Museum, Vienna, initiated a research project on corrosion effects of gold coins. By now, investigations on historic and contemporary coins included optical microscopy, scanning electron microscopy (SEM), Auger electron microscopy (AES), X-ray photoelectron microscopy (XPS), and electrochemical methods showing the distribution of pollutants.This work focuses on secondary ion mass spectrometry (SIMS) investigations merely showing the distribution of electronegative elements, such as sulfur, oxygen, and chlorine on the surface. Sulfur is highly suspected of causing the observed corrosion phenomena, and is indeed enriched near polluting splints. Since SIMS is a destructive method, the investigated samples are test coins with intentionally added impurities. These coins were manufactured in cooperation with the Austrian Mint. They were treated with potassium polysulfide (K2Sx) for 8 h gaining a rapid corrosion of the surface.SIMS mass spectra, depth profiles, and images were done (a) at non-polluted areas, (b) near polluted areas with slight coloring, and (c) directly at polluting stains showing enrichments of sulfur and chlorine. Due to the success of these investigations further studies on historic coins are intended.  相似文献   

20.
Microchemical investigations were carried out on ancient silver coins originated from the same country but of different historical periods between the fifth and the second centuries B.C. Energy-Dispersive X-ray microanalysis in a Scanning Electron Microscope (SEM-EDX) was employed to obtain qualitative and semi-quantitative information about the chemical composition of these coins. SEM-EDX analyses employ an electron beam of 20?keV, which interacts with the sample leading to the emission of characteristic X-rays, to determine elements present in the surface patina, closely related to the sample preservation. In the X-ray photoelectron spectroscopy (XPS) analysis a monochromatic Al Kα radiation (1486.6?eV) interacts with the sample and photoelectrons are detected as secondary radiation, to investigate about coins elemental composition. Moreover a beam of Ar+ ions with an energy of 3?keV was used for the sputtering procedure in order to perform depth profile measurements, from the surface (patina composition) down to deeper layers. Useful information about production, chronological period and utilization places of coins are obtained to support a correct dating of these samples.  相似文献   

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