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1.
Solid state nuclear track detectors are commonly used for measurements of concentrations of radon gas and/or radon progeny. All these measurements depend critically on the thickness of the removed layer during etching. However, the thickness of removed layer calculated using the etching period does not necessarily provide a sufficiently accurate measure of the thickness. For example, the bulk etch rate depends on the strength of stirring during etching for the LR 115 detector. We propose here to measure the thickness of the removed layer by using energy-dispersive X-ray fluorescence spectrometry. In the present work, a reference silver nitrate pellet is placed beneath the LR 115 detector, and the fluorescence X-ray intensity for silver is then measured. We have found a linear relationship between the X-ray intensity and the thickness of the removed layer for LR 115 detector. This provides a fast method to measure the thickness of removed layer from etching of LR 115 detector. However, this method was found to be inapplicable for the CR-39 detector. Therefore, alternative methods have yet to be explored for the CR-39 detector. 相似文献
2.
Anna Worobiec Lucyna Samek Zoya Spolnik Velichka Kontozova Elzbieta Stefaniak René Van Grieken 《Mikrochimica acta》2006,156(3-4):253-261
The St. Michael Archangel’s Church in Szalowa, Poland, was selected for closer investigation with respect to the indoor/outdoor
air exchange and its influence on the air quality and work arts preservation. Chemical composition, size and abundance of
particulate matter and concentration of gases NO2, SO2, O3 inside and outside the church were determined. To study seasonal variation of the weather condition (temperature, inversion
level, wind direction) and the influence of seasonal sources of the air pollution (like heating of the nearby houses), samples
were collected in winter and summer time. It was stated that suspended particulate matter inside the wooden church has in
general an outdoor source. Several groups of particles were distinguished such as the organic ones, soil dust, nitrates and
sulphates. In case of organic and soil dust particles, the concentration inside was higher than outside. From the results,
in comparison to literature data, one can conclude that accumulation of particulate suspended matter in the church is more
intense than in other types of buildings. Gaseous pollutants were detected but their concentration was negligible. 相似文献
3.
Ricardo H. M. Godoi Ana F. L. Godoi Anna Worobiec Sandro J. Andrade Johan de Hoog Mary R. Santiago-Silva Rene Van Grieken 《Mikrochimica acta》2004,145(1-4):53-56
Biomass burning is an important primary and secondary source of aerosol particles. The presence of carbonaceous particles in the respirable size range makes the study of this fraction important in view of possible health and climatic effects. The annual burning of sugar cane plantations causes emission of huge amounts of pyrogenic particles. Aerosol samples were collected in Araraquara city, São Paulo state, Brazil, during the harvest season for fine and coarse particles and bulk; they were analysed by electron-probe microanalysis, including facilities for low-Z element determination (low-Z EPMA) and by energy-dispersive X-ray fluorescence (EDXRF), in order to investigate the elemental composition of individual particles and bulk samples, respectively. Numerical analysis of the EPMA results by hierarchical clustering shows high contributions of carbonaceous particles that can be distinguished mainly in two different types: biogenic and carbon-rich. Additionally, two significant contributions of aluminosilicate particles were identified: as rather pure aluminosilicates or mixed with carbonaceous species. The EDXRF results are compatible with those of aerosol particles in Amazon, which is nowadays one of the main sources of biogenic particles in the world. 相似文献
4.
能量色散偏振X射线荧光光谱法测定生铁中锰和钛 总被引:1,自引:0,他引:1
探讨了应用能量色散偏振X射线荧光光谱仪测定生铁中锰和钛进行炉前快速分析的方法.对测定锰及钛时仪器的工作条件,试样的制备以及工作曲线的制作等因素作了较系统的试验,该方法所得测定结果与化学法测定结果或标样标准值相吻合,相对标准偏差小于1.5%,与化学法相比,锰和钛的测定时间由50 min缩短到2 min. 相似文献
5.
利用能量色散X射线荧光光谱法(energy disperse X-ray fluorescence,EDXRF)对浙江嵊州小黄山与河南舞阳贾湖两处新石器时代前期遗址出土陶器的主量元素化学组成进行了分析测定.结果显示,这两处遗址出土陶器的化学组成地域特征明显,与贾湖遗址相比,小黄山遗址陶器具有我国南方陶瓷器普遍存在的“高... 相似文献
6.
能量色散X荧光分析(EDXRF)过程中,存在吸收增强效应影响分析准确性的问题。利用EDXRF测量Fe、Ni、Zn三种元素与Cu的六组伪二元系样品,根据实验结果对元素间的影响特征和影响程度进行了分析。并利用La-chance-Trail算法得到三组元素间的影响因子数值,Cu和Fe以及Cu和Zn之间的影响效应随元素含量变化较明显,分别在0.38~0.70和0.43~0.65之间,Cu和Ni之间的影响效应不明显。对Cu-Zn二元系中Cu含量实际计算结果相对误差均在5%以内。 相似文献
7.
Sofia Pessanha Maria Luisa Carvalho Maria Becker Alex von Bohlen 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The purpose of this study is to determine the elemental content, namely heavy metals, of samples of vine-leaves, grapes must and wine. In order to assess the influence of the vineyard age on the elemental content throughout the several stages of wine production, elemental determinations of trace elements were made on products obtained from two vineyards aged 6 and 14 years from Douro region. The elemental content of vine-leaves and grapes was determined by Energy Dispersive X-Ray Fluorescence (EDXRF), while analysis of the must and wine was performed by Total Reflection X-ray Fluorescence (TXRF). 相似文献
8.
偏振激发-能量色散X-射线荧光光谱法快速分析地质样品中34种元素 总被引:22,自引:0,他引:22
报道了利用偏振激发 能量色散X 射线荧光光谱法快速定量分析地质样品中 34种元素所得到的结果。制样方法采用粉末压片法。原子序数低于Fe的元素采用基本参数法 ,Fe及其他元素采用散射线内标法进行校准。实验中分别采用了高取向热解石墨 (HOPG) ,Al2 O3 ,Mo ,Co等不同偏振靶 (或二级靶 ) ,对目标元素组进行选择激发和探测。在总测量时间为 6 0 0s·(每个样品 ) -1的条件下 ,得到的各元素的检出限达到 0 5~ 30 μg·g-1。 相似文献
9.
Nuray Kup Aylikci 《光谱学快报》2013,46(6):346-355
AbstractIn this study, Kα1,2, Kβ1,3, and Kβ2,4 X-ray natural line widths for various elements were determined semi-empirically at 123.6?keV by using K shell fluorescence yields obtained from energy dispersive X-ray fluorescence measurements. The obtained results contribute to a database for the development of new theoretical models of atomic structure, radiation shielding materials, and designing new technological devices related to the structural analysis of materials. The obtained results were compared with the literature, while new fitting polynomials for the studied parameters were acquired. The results showed that the natural linewidths of K X-ray lines fit fourth-order polynomials except for Kβ2,4. 相似文献
10.
Assessment of bone calcium and phosphorus content using micro X‐ray fluorescence spectrometry (μ‐EDXRF): effects of long‐term cadmium poisoning
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This study assesses whether the concentrations of biologically important elements in bones are altered by long‐term consumption of cadmium (Cd)‐contaminated water. Heavy metal poisoning has significant impact on humans, and pollutants such as Cd are often found at high concentrations in waterways. Twelve Sprague Dawley rats consumed water with 50 p.p.m. Cd (Cd group), and another 12 consumed normal water (control group). Six subjects from each group were sacrificed after 2 weeks and the others after 4 weeks. Spectra were acquired from the femur by using the EDAX Eagle III micro‐XRF setup, and quantitative calculations were performed by using the fundamental parameter method to determine the concentrations of elements. A bone calcium/phosphorus concentration ratio (Ca/P) of 2.07 ± 0.001 is observed in the spectra from control subjects after 2 weeks and 2.07 ± 0.001 after 4 weeks. In Cd subjects, Ca/P after 2 weeks is 2.04 ± 0.001 and after 4 weeks is 1.97 ± 0.003. Statistically significant differences are obtained when comparing controls with Cd subjects at both time points and when comparing Cd subjects at both time points. Cadmium poisoning significantly affects bone Ca and P concentrations, increasing the likelihood of osteoporosis and other bone diseases. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献