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视觉的盛宴——浅析影视动画中光线的作用 被引量:4
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作者 关媛 《电影文学》 北大核心 2008年第3期127-127,共1页
光线是作为一种"词汇"来表达创作者的思想感情和审美理想,是一切艺术都要触及、表现和探索的对象。影视动画作品是通过镜头画面向人们传达信息的,这种电影语言又不同于文字的表述方式,而光线则是镜头画面中有着重要作用的元... 光线是作为一种"词汇"来表达创作者的思想感情和审美理想,是一切艺术都要触及、表现和探索的对象。影视动画作品是通过镜头画面向人们传达信息的,这种电影语言又不同于文字的表述方式,而光线则是镜头画面中有着重要作用的元素。从影视动画镜头画面的特性看,浅析光线元素所具有的戏剧性和假定性等作用。影视动画作品中的光线已经成为影视动画中特有的造型语言,具有自身独特的魅力。 展开更多
关键词 影视动画 光线元素 光线元素的作用
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Scheme for Concentration of Unknown Photonic GHZ Entangled States via Linear Optical Elements 被引量:1
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作者 ZHANG Gang YANG Ming CAO Zhuo-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期853-856,共4页
We propose two schemes to concentrate unknown nonmaximally tripartite GHZ entangled states via linear optical elements. The finial maximally entangled states obtained from our schemes are shared by two or three partie... We propose two schemes to concentrate unknown nonmaximally tripartite GHZ entangled states via linear optical elements. The finial maximally entangled states obtained from our schemes are shared by two or three parties. Our schemes only need polarizing beam splitters and single-photon detectors. In addition, the schemes can be demonstrated within current experimental technology. 展开更多
关键词 unknown photonic GHZ entangled states CONCENTRATION linear optical elements
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The distribution and variation of elements in sediments off the Huanghe (Yellow) River mouth 被引量:3
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作者 乔淑卿 石学法 +4 位作者 高晶晶 刘焱光 杨刚 朱爱美 王昆山 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期876-885,共10页
Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray f... Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray fluorescence spectrometry. Results demonstrate that sediment grain size is the dominant factor controlling the spatial variations of elemental concentrations. Correlation and cluster analyses allowed classification of the study area into four geochemical regions: Regions Ⅰ and Ⅲare characterized by high concentrations ofAl2O3, Fe2O3, MgO, Na2O, K2O, Cr, Cu, Mn, Ni, Pb, V, and Zn, and contain fine-grained sediments with mean grain size (Mz)〈22 μm; and; Regions Ⅱ and Ⅳcontain mostly coarse-grained sediments, and are characterized by high concentrations of SiO2, Na2O, and Zr. The sediment entering the sea from the Huanghe River and its tributaries is enriched in Ca. Thus, the Ca/Al ratio was used as an indicator of the proportion of sediments in the study area that originated from the Huanghe River. Ca/Al ratios decrease from Regions Ⅰ and Ⅱ(located in the nearshore zone of the Huanghe River delta) to Regions Ⅲand Ⅳ(distributed in the offshore zone of the northern Huanghe River delta, southern and southeastern Laizhou Bay area). 展开更多
关键词 Huanghe (Yellow) River Bohai Sea major and trace elements grain size heavy metals
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Prediction of XRF analyzers error for elements on-line assaying using Kalman Filter 被引量:3
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作者 Nakhaei F Sam A +1 位作者 Mosavi MR Nakhaei A 《International Journal of Mining Science and Technology》 SCIE EI 2012年第4期595-601,共7页
Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods i... Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods including chemical methods,X-ray fluorescence and atomic absorption spectrometry are advanced and accurate.However,in some applications,such as on-line assaying process,high accuracy is required.In this paper,an algorithm based on Kalman Filter is presented to predict on-line XRF errors.This research has been carried out on the basis of based the industrial real data collection for evaluating the performance of the presented algorithm.The measurements and analysis for this study were conducted at the Sarcheshmeh Copper Concentrator Plant located in Iran.The quality of the obtained results was very satisfied;so that the RMS errors of prediction obtained for Cu and Mo grade assaying errors in rougher feed were less than 0.039 and 0.002 and in final flotation concentration less than 0.58 and 0.074,respectively.The results indicate that the mentioned method is quite accurate to reduce the on-line XRF errors measurement. 展开更多
关键词 PredictionAccuracyX-ray fluorescence Kalman FilterAssayingError
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A Comparison between Neutron Activation Analysis and X-Ray Fluorescence Methods in Analyzing the Granite Samples
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作者 Hayder Salah Naeem Pegah Moradi Khaniabadi Eid Mahmoud Eid 《Journal of Chemistry and Chemical Engineering》 2013年第9期803-807,共5页
This study focused on the performance of where elements analysing techniques were used to detect the elements in granite stones. These techniques are NAA (neutron activation analysis) and XRF (X-ray fluorescence).... This study focused on the performance of where elements analysing techniques were used to detect the elements in granite stones. These techniques are NAA (neutron activation analysis) and XRF (X-ray fluorescence). They were applied to detect the elements in samples which had been chosen from different areas of Pulua Penang in Malaysia collected by geophysics group which helped to describe and identify the elements found in the granite stone that were used in the study procedures to control the analytical results. The integration of both methods has enabled the researcher to determine 40 elements in the samples. The numbers of elements detected by XRF analysis method are 12 elements (Ar, K, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn); while, the elements detected by NAA method have three folds of elements with XRF analysis method were 35 elements (Na, AI, Si, K, Ca, Sc,Ti, Mn, Fe, Co, Ga, Ce, As, Br, Rb, Zr, Sb, I, Cs, Ba, La, Nd, Sm, Eu,Tb, Dy, Yb, Lu, Hf, Ta, W, Au, Pa and Np). Seven common elements were detected in both techniques: K, Sc, Ti, V, Mn, Fe and Co. Si has a higher concentration in NAA technique which is 331.8 ppm. Sc has a lower concentration in XRF technique which is 0.25 ppm. Nd has a lower concentration in NAA technique which is 3.09 - 10-5 ppm. Finally, it is found that the NAA is better to detect the elements than XRF. 展开更多
关键词 Radiation science radiation physics NAA XRF analyzing methods.
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Geochemical characteristics and mode of occurrence of trace elements in coal at West Bokaro coalfield 被引量:5
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作者 Sk. Md. Equeenuddin Subhasish Tripathy +1 位作者 Prafuila Kumar Sahoo Amit Ranjan 《International Journal of Coal Science & Technology》 EI 2016年第4期399-406,共8页
The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes o... The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes of occur- rence. Elemental concentrations with reference to their crustal abundances indicated that coals are relatively enriched in As (4.4-15.5 mg/kg), Cd (0.3-3.0 mg/kg), Cu (28.0-68.1 mg/kg) and V (46.6-178.0 mg/kg); depleted in Co (10.8-28.4 mg/ kg), Mn (7.6-483.4 mg/kg), Ni (13.0-31.6 mg/kg), Cr (14.2-85.5 mg/kg) and Zn (5.25-70.4 mg/kg). The concentration of As, Cd, Co, Cu and V were higher than the average values of world and Indian coals. Mineralogical study carried out by X-ray diffraction shows that quartz and kaolinite occur as dominant mineral phases in this coal. Fourier transform infrared spectroscopy pattern suggests organic structures primarily containing aromatic nuclei, aliphatic side chain and some oxygen containing groups. The modes of occurrence of trace elements present in these coals have been determined through statistical approach. Both Cu and Cr are more closely associated with mineral matter, whereas Co is dominantly present with its organic form. The concentrations of Cd, Mn, Ni, Zn, As and V have apparently occur in both organic and inorganic constituents. This study would be helpful to assess the potential environmental impacts during mining and combustion of this coal. 展开更多
关键词 MINERALOGY Organic group Trace elements COAL West Bokaro
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Geochemical characteristics of illite clay rocks from the Shihezi Formation in the Hanxing mining area and its sedimentary environment
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作者 Xu Bohui Ding Shuli +1 位作者 Wang Yu Liu Qinfu 《Mining Science and Technology》 EI CAS 2011年第4期495-500,共6页
We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrome... We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrometry. The results show that the amount of SiO2 is between 53.37% and 61.58% (by weight) and that of Al2O3 22.40% and 31.31% (by weight). The ratio of SiO2/Al2O3 lies between 1.71 and 2.75. The amount of K2O ranges from 1.11% to 2.56% (by weight). The amounts of Fe and Ti are higher than the theoretical values in illite clay rock would indicate. The amounts of some trace elements, such as Ga, As, Ba, Cu, Th and U are higher than their Clark values, while that of another 23 trace elements are found to be dose to their Clark values. The amounts of REE range from 22.59 to 570.54 μg/g, with an average of 163.23μg/g. The ratios of LREE/HREE range from 5.41 to 21.82, with an average of 8.87. These characteristics show that LREE are much richer in content than HREE. The REE distribution patterns of our samples were characterized by clearly negative Ce and Eu anomalies. We analyzed the sedimentary environment of the Hanxing mining area in Late Permian by the characteristic element ratio method. The ratios of Mn/Fe range from 0 to 0.0168, which are lower than those in a marine sedimentary environment. The ratios of Sr/Ba (0.20-0.41) are less than 1. These are all indications that the sediments of the Hanxing mining area in Late Permian form largely a continental sedimentary environment. The sedimentary water is freshwater, a conclusion reached on the basis of the ratios of Th/U (2.66-6.62) and of Ca/(Ca + Fe) (0.01-0.059); the average ratio of Fe2+/Fe3+ is 4.8. The sedimentary water condition is weakly acidic and weakly oxidative-weakly reductive, a conclusion reached on the basis of ratios of Fe2+/Fe3+ (4.8) and of Ceanom (-0.08). 展开更多
关键词 Hanxing mining arealllite Trace elements Geochemical Sedimentary environment
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Effect of Exogenous Organic Matter Application on Soil and Plant Elemental Composition in Pot Experiments
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作者 Eubica Pospislova Magdalena Habova +2 位作者 Eva Dolezelova Ida Drapelova Veronika Renciukova 《Journal of Life Sciences》 2016年第3期153-160,共8页
Content of macro- and microelements in plant and soil was studied after biochar, compost, digestate, lignite, and lignohumate application. Pot experiments were carried out in Phytotron CLF Plant Master (Wertingen, Ge... Content of macro- and microelements in plant and soil was studied after biochar, compost, digestate, lignite, and lignohumate application. Pot experiments were carried out in Phytotron CLF Plant Master (Wertingen, Germany). As tested plant lettuce (Lactucasativa) was used. Elemental composition was determined by AAS and XRF spectroscopy. Macronutrients content (Ca, Mg, K, and P) was determined by Mehlich III. Total content of carbon and nitrogen were determined by LECO TruSpec CN analyser. Results showed that different exogenous organic amendments statistically significantly influenced macro and micronutrients content in soil and plant. Satisfactory C/N ratio for soil microorganisms was measured only after compost and digestate application. As concerns hazardous elements, no legislation limits were overstepped after application of the tested organic amendments. Bioavailability and their uptake by plants followed the order: Cd 〉 Mn 〉 Zn 〉 Fe. 展开更多
关键词 Haplic Cambisol macro and micro elements AAS XRF spectroscopy.
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Influence of Ice on Soil Elemental Characterization via Portable X-Ray Fluorescence Spectrometry 被引量:4
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作者 D.C.WEINDORF N.BAKR +6 位作者 Y.ZHU A.MCWHIRT C.L.PING G.MICHAELSON C.NELSON K.SHOOK S.NUSS 《Pedosphere》 SCIE CAS CSCD 2014年第1期1-12,共12页
Field portable X-ray fluorescence (PXRF) spectrometry has become an increasingly popular technique for in-situ elemental characterization of soils. The technique is fast, portable, and accurate, requiring minimal sa... Field portable X-ray fluorescence (PXRF) spectrometry has become an increasingly popular technique for in-situ elemental characterization of soils. The technique is fast, portable, and accurate, requiring minimal sample preparation and no consumables. However, soil moisture 〉 20% has been known to cause fluorescence denudation and error in elemental reporting and few studies have evaluated the presence of soil moisture in solid form as ice. Gelisols (USDA Soil Taxonomy), permafrost-affected soils, cover a large amount of the land surface in the northern and southern hemispheres. Thus, the applicability of PXRF in those areas requires further investigation. PXRF was used to scan the elemental composition (Ba, Ca, Cr, Fe, K, Mn, Pb, Rb, Sr, Ti, Zn, and Zr) of 13 pedons in central and northern Alaska, USA. Four types of scans were completed: 1) in-situ frozen soil, 2) re-frozen soil in the laboratory, 3) melted soil/water mixture in the laboratory, and 4) moisture-corrected soil. All were then compared to oven dry soil scans. Results showed that the majority of PXRF readings from in-situ, re-frozen, and melted samples were significantly underestimated, compared to the readings on oven dry samples, owing to the interference expected by moisture. However, when the moisture contents were divided into 〉 40% and 〈 40〈 groups, the PXRF readings under different scanning conditions performed better in the group with 〈 40% moisture contents. Most elements of the scans on the melted samples with 〈 40% moisture contents acceptably compared to those of the dry samples, with R2 values ranging from 0.446 (Mn) to 0.930 (St). However, underestimation of the melted samples was still quite apparent. Moisture-corrected sample PXRF readings provided the best correlation to those of the dry, ground samples as indicated by higher R2 values, lower root mean square errors (RMSEs), and slopes closer to 1 in linear regression equations. However, the in-situ (frozen) sample scans did not differ appreciably from the melted sample scans in their correlations to dry sample scans in terms of R2 values (0.81 vs. 0.88), RMSEs (1.06 vs. 0.85), and slopes (0.88 vs. 0.92). Notably, all of those relationships improved for the group with moisture contents 〈 40%. 展开更多
关键词 Gelisols MOISTURE PERMAFROST proximal sensing regression
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Quantitative analysis of elements (C,N,O,Al,Si and Fe) in polyamide with wavelength dispersive X-ray fluorescence spectrometry 被引量:3
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作者 LAI MeiShuang XIANG LeiWen +1 位作者 LIN Jin-Ming LI Hai-Fang 《Science China Chemistry》 SCIE EI CAS 2013年第8期1164-1170,共7页
A wavelength dispersive X-ray fluorescence (WD-XRF) spectrometry combined with calibration curve method was estab- lished for simultaneously analyzing low-Z elements (C, N, O) and A1, Si, Fe in polyamide. To inves... A wavelength dispersive X-ray fluorescence (WD-XRF) spectrometry combined with calibration curve method was estab- lished for simultaneously analyzing low-Z elements (C, N, O) and A1, Si, Fe in polyamide. To investigate the origin of plastic material causing deposition and blocking in instrument engines and pipelines, polyamide 6 (PA 6, an engineering plastic) was chosen as the study object on account of its common use in industry. The sample preparation with pressed powder disk has been developed for determination of six elements in PA 6. Pure Cu metal was used as the matrix and PA 6 was regarded as standard sample for C, N, O elements. PA 6 particles were firstly smashed to uniform powder in liquid nitrogen, and then mixed with inorganic standard powders (Fe203, A1203, SIO2, and Na2SiO3). The mixture was ground to obtain homogeneous calibration materials for WD-XRF analysis. The quantitative property of the calibration curve method for each element was re- liable. The limits of detection (S/N≤3) of C, N, O, A1, Si and Fe using WD-XRF were 249, 120, 101, 6.2, 3.3, and 1.8 μg/g, respectively. To confirm the accuracy of the proposed WD-XRF calibration curve method, inductively coupled plasma optical emission spectroscopy (ICP-OES) detection for A1, Si, Fe and elemental analyzer (EA) analysis for C, N, O were utilized. A good correlation of the WD-XRF results with the measurements of ICP-OES and EA was observed. 展开更多
关键词 X-ray fluorescence low-Z elements polyamide 6
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