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1.
繁昌窑青白瓷胎体配方工艺一直停留在理论推理阶段,尚未有确凿的测试数据和模拟实验加以证实。为深入探究繁昌窑的胎料配方工艺,选取了繁昌窑址附近的多种瓷土样品进行了测试分析,并采用了古代制瓷工艺进行了模拟烧制。主要运用了波长色散X射线荧光光谱法(WDXRF)、红外光谱(FTIR)和X射线衍射(XRD)等光谱分析方法对瓷土成分进行测试;借助同步热分析(TG-DSC)对样品烧造温度进行了探索;通过模拟烧制陶瓷样品,对繁昌窑青白瓷的烧制工艺进行了研究,并对烧制的陶瓷样品进行显微结构分析。研究表明,繁昌窑附近的几种瓷土无论是单独制胎还是添加高岭土混合制胎,其烧成温度皆接近古代繁昌窑青白瓷的烧制温度。繁昌窑附近的瓷土是可以作为制作古代青白瓷的原料之一,但由于其中的铝含量较低,不能单独用来制作青白瓷胎体的原料,繁昌窑青白瓷在制作过程中应添加了其他富铝类原料。该研究对探索古代繁昌青白瓷的生产工艺及其蕴含的科学价值,提升繁昌窑在中国陶瓷工艺技术发展史上的地位等具有重要的学术意义,并可为现代陶瓷产业技术改进提供有益启示。  相似文献   
2.
This work was aimed at improving the instrumental sensitivity and detection limits for Cd determination in liquid samples by using conventional Wavelength Dispersive X-ray Fluorescence (WDXRF) instrumentation equipped with Rh-anode X-ray sources.  相似文献   
3.
Multilayered samples consisting of Al, Co and Ni nanolayers were produced by MBE and characterized nondestructively by means of SRXRF, μ-XRF, WDXRF, RBS, XRR, and destructively with SIMS. The main aims were to identify the elements, to determine their purity and their sequence, and also to examine the roughness, density, homogeneity and thickness of each layer. Most of these important properties could be determined by XRF methods, e.g., on commercial devices. For the thickness, it was found that all of the results obtained via XRR, RBS, SIMS and various XRF methods (SRXRF, μ-XRF, WDXRF) agreed with each other within the limits of uncertainty, and a constant deviation from the presets used in the MBE production method was observed. Some serious preliminary discrepancies in the results from the XRF methods were examined, but all deviations could be explained by introducing various corrections into the evaluation methods and/or redetermining some fundamental parameters.  相似文献   
4.
An X-ray fluorescence method (XRF) is presented that allowed low detection limits (at the 0.1–23 ng mL−1 level) to be obtained for Cr, Mn, Fe, Ni, Zn, Sr, Pb, Bi and Br in water. The samples were prepared using a thin layer method. Trace elements were determined via the calibration curve and standard addition. Absorption effects and inhomogenities in prepared samples were checked for using the emission–transmission method and internal standards, respectively. The results from the XRF method were compared with the results from the inductively coupled plasma atomic emission spectrometry method.   相似文献   
5.
Fruit flies (Drosophila melanogaster) were exposed to low temperature (4 °C, 3d), after controlled acclimation (15 °C, 1d) and passed to artificial hibernation. The concentrations of elements in almost 1000 mature flies were measured by Wavelength-Dispersive X-ray Fluorescence (WDXRF) spectrometry. Concentration changes of Zn, K, S, Ca (33.5%, 11.2%, 10.3% and 7.5%, respectively) and especially Cr and Mn (99.90 and 99.60) were observed. Concentrations of Cr, Zn, S and Ca increased significantly, but concentrations of Mn and K decreased in with comparison to the control group.  相似文献   
6.
In multichannel wavelength-dispersive X-ray fluorescence spectrometry (WDXRF) the fluorescence intensity might depend on grain size and heterogeneity of the sample. Six river Nile sediment samples were collected two meters below the water surface from different locations covering the greater Cairo, Egypt. Each sample was dried at 65 °C for 48 h and divided into four grain size fractions: < 32 μm, 32–63 μm, 63–125 μm and 125–200 μm using different sieves. The dry sediment samples were mixed with low contamination binder (Wax, C6H8O3N2) in a mass ratio of wax:sample = 4:0.9 g. Sample pellets were made using a hydraulic press at a pelletizing pressure of 120 KN cm− 2. The results show that the XRF intensities of the Kα radiation might increase or decrease with decreasing grain size, depending on the atomic number of the analyte. In the present thick pelletized samples, the penetration depth of the characteristic radiation increases at low grain sizes, and consequently the probability of the grain-size effect on the characteristic radiation decreases. Depending on the experimental data, a general theoretical equation, relating fluorescence intensity, grain size and atomic number, was derived by using cubic spline interpolation. The fractions were identified by WDXRF using standardless quantitative analysis, depending on the fundamental parameter approach. According to the present statistical analysis and the Certified Reference Material (CRM) results, the quantitative analysis results were found acceptable when the grain size of the river Nile sediments less than 32 μm. At a grain size > 63 μm, standardless analysis using fundamental parameter approach was found to be useful for qualitative and semi-quantitative analysis only whereas there are a strong positive correlations.  相似文献   
7.
This work reports results from a chemico-physical study of the stained glass window of the southern transept of St. Anthony's Basilica (Padova, Italy), dated to the late 19th century AD. Selected samples of glass with or without grisailles were characterised by means of various X-ray spectrometric techniques, such as wavelength dispersive X-ray fluorescence, electron microprobe, and scanning electron microscopy with energy dispersive X-ray microanalysis, coupled, in some cases, with X-ray powder diffraction. Integration of analytical results revealed many types of glass related to different phases of the “life” of stained glass, and the production technology of grisailles. In addition, the degree of damage undergone throughout the last century due to materials used in the production of windows was studied, to design and optimise a combined conservation and restoration strategy. Lastly, another important aim of the present study was to amplify the database on 19th-century stained glass windows, little documented in the literature.  相似文献   
8.
The technique has been developed for the quantification of small tantalum, cesium, barium, lanthanum, cerium, and neodymium concentration in rocks with X‐ray wavelength dispersive spectrometer S8 TIGER (Bruker AXS, Germany). The optimum conditions have been chosen for registration of the analyzed elements characteristic radiation and background positions. To determine the concentrations of analyzed elements accurately, the contribution of overlapping lines to the experimental intensities of the analytical lines has been taken into account. The sample of mass about 1.2 g has been pressed into pellet by the hydraulic press. Metrological studies showed that the accuracy in the determination of the concentration of analyzed elements for the developed technique meets the requirements for methods of III accuracy class. The Ta detection limits calculated for TaLβ1‐analytical and CsLα1‐analytical lines were 2.6 and 3.4 ppm, respectively. The detection limit of Ba, La, Ce, and Nd was (in ppm), respectively, 4.3, 2.7, 5.8, and 4.7. The metrological characteristics of the previously developed and adapted techniques were compared. Ta concentration in granite pegmatite samples has been quantified. The samples of the highest tantalum content have been investigated additionally by powder diffraction and X‐ray microprobe analysis. The X‐ray diffraction method turned out to be insensitive to the detection of mineral phase of tantalum niobates, while micro‐XRF allowed detecting its presence in tourmaline grains. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
9.
Spectra of K X-rays emitted from pure 3d transition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy (WDXRF). The measurements were performed using a ZSX-100e sequential spectrometer equipped with an Rh X-ray tube operated. An accurate analytical representation of each line was obtained by a fit to a Lorentz function. The spectra were analyzed in order to examine the K X-ray peak parameters such as asymmetry index, peak energy and relative intensity ratios. The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.  相似文献   
10.
利用波长色散型X射线荧光光谱(WDXRF)和傅里叶变换红外光谱(FTIR)对环抚仙湖分布的澄江学山、金莲山和江川光坟头3个古滇国遗址出土的陶器从化学、结构组成以及烧成温度3方面进行了初步分析.WDXRF主次量元素分析结果表明,各遗址同类陶器(尤其是红陶)的基本制陶原料具有相似性,黑(褐)陶中添加的助熔剂含量明显高于红陶.FTIR分析结果显示同类陶器中包含的矿物具有一致性,红陶中含有石英和疑似铁矿物,黑(褐)陶中则都添加了大量的碳酸盐矿物.基于FTIR结果还对两类陶器的烧成温度做出了初步判断,估计黑(褐)陶在600-700℃,红陶在800℃左右.黑(褐)陶中较高含量的助熔剂可能在降低烧成温度方面起到了重要作用.以上初步分析表明,3个遗址出土的同类陶器在原料选择和烧成温度方面具有相似处,遗址间可能存在密切的联系.  相似文献   
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