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五线谱和简谱在中国的演进及其对中国音乐传统记谱法的影响 被引量:11
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作者 廖红宇 《乐府新声(沈阳音乐学院学报)》 2006年第3期52-58,共7页
五线谱和简谱传入中国后,得到了广泛的运用,其记谱法在中国传统音乐运用过程中的演进主要体现有:记写音高、时值、节奏、节拍、速度等符号的变革,更适应于表达中国传统音乐的特点;在器乐和声乐表演的记谱中产生了许多新的技法符号,呈... 五线谱和简谱传入中国后,得到了广泛的运用,其记谱法在中国传统音乐运用过程中的演进主要体现有:记写音高、时值、节奏、节拍、速度等符号的变革,更适应于表达中国传统音乐的特点;在器乐和声乐表演的记谱中产生了许多新的技法符号,呈现出中西融合的特点。此外,两者对中国传统音乐记谱法都产生了一定的影响。 展开更多
关键词 线谱/简谱/记谱/中国传统音乐记谱/演进/影响
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矢量水听器方位估计方法研究
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作者 吉海鹏 《中国水运(下半月)》 2019年第3期83-84,共2页
矢量水听器能够在空间中同一点,同时的测量声场中的声压和振速信息,再通过对信息的一起处理,实现对目标的方位估计。根据船舶辐射噪声形式和干扰的不同,有多种估计方法。本文介绍了平均声强器法和线谱法的原理,并对它们做了计算机仿真,... 矢量水听器能够在空间中同一点,同时的测量声场中的声压和振速信息,再通过对信息的一起处理,实现对目标的方位估计。根据船舶辐射噪声形式和干扰的不同,有多种估计方法。本文介绍了平均声强器法和线谱法的原理,并对它们做了计算机仿真,得出了在不同信号形式和干扰条件下它们的不同应用。 展开更多
关键词 矢量水听器 方位估计 线谱法 平均声强
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古筝教学中简谱与五线谱交互使用案例 被引量:1
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作者 顾梦园 刘永福 《北方音乐》 2019年第17期129-130,共2页
音乐教学中弘扬民族音乐,传播民族音乐文化,是增强民族自信心、振奋民族精神的需要。我国民族乐器长期使用简谱记谱,随着时代的发展,社会不断的进步,中国民族乐器古筝的影响力日益提升,为更好地传播古筝音乐文化,使古筝愈发国际化,五线... 音乐教学中弘扬民族音乐,传播民族音乐文化,是增强民族自信心、振奋民族精神的需要。我国民族乐器长期使用简谱记谱,随着时代的发展,社会不断的进步,中国民族乐器古筝的影响力日益提升,为更好地传播古筝音乐文化,使古筝愈发国际化,五线谱记谱法的运用成为趋势。 展开更多
关键词 古筝教学 简谱记谱 线谱记谱
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扬琴演奏的记谱法
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作者 奚文 《剧影月报》 2004年第4期43-43,共1页
首调记谱法和固定调记谱法在我国目前五线谱和简谱两种记谱中都有运用。简谱首调记谱法也就是我们通常所说的简谱首调唱名法,是我们学习演奏民族器乐时最常用的记谱法。这种记谱法是前辈们勤索苦探、弃粕存精,总结出的一套“中国式的... 首调记谱法和固定调记谱法在我国目前五线谱和简谱两种记谱中都有运用。简谱首调记谱法也就是我们通常所说的简谱首调唱名法,是我们学习演奏民族器乐时最常用的记谱法。这种记谱法是前辈们勤索苦探、弃粕存精,总结出的一套“中国式的”记谱方法。扬琴于十七世纪从西洋传人我国以来,在不断汉化、发展的过程中。 展开更多
关键词 扬琴 演奏艺术 简谱首调记谱 线谱固定调记谱 作曲手
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Distribution and occurrence of trace elements in the No.14 coal from the Huolinhe mine 被引量:5
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作者 Xiangfei Bai Yue Wang Wenhua Li 《International Journal of Coal Science & Technology》 EI 2017年第3期199-213,共15页
Optical microscopy, and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry (SEM-EDX), have been used to study the minerals and the concentrations of 12 trace elements in the No.14 c... Optical microscopy, and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry (SEM-EDX), have been used to study the minerals and the concentrations of 12 trace elements in the No.14 coal from the Huolinhe mine, Inner Mongolia China. The distribution, affinity and removability of the trace elements were studied by float-sink experiments and petrological methods. A high mineral content, dominated by clay minerals, was found in the No.14 coal from the Huolinhe mine. The concentrations of As, Sb and Hg are relatively high compared to the average values for Chinese coals. As, Cr, Hg, Li, Mn, Pb are mainly associated with the minerals while Cd, Co, Ni, Sb, and Se are evenly distributed between the minerals and the organic matter. Be and Ba are mainly distributed in the minerals with a minor proportion in the organic matter. Most elements have a low organic affinity, although Sb, Se, Co, Cd, Ni are closely integrated with the organic matter. High theoretical removabilities are indicated for most trace elements. So it may be possible to lower the concentrations of trace elements during coal preparation. 展开更多
关键词 Trace elements Modes of occurrence - Organic affinity REMOVABILITY Huolinhe coal
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Characterization and recycling of nickel- and chromium-contained pickling sludge generated in production of stainless steel 被引量:11
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作者 李小明 谢庚 +2 位作者 HOJAMBERDIEV Mirabbos 崔雅茹 赵俊学 《Journal of Central South University》 SCIE EI CAS 2014年第8期3241-3246,共6页
Pickling sludge generated during the neutralization of pickling wastewater with calcium hydroxide in stainless steel pickling process was characterized using X-ray fluorescence spectrometry, X-ray diffractometry, scan... Pickling sludge generated during the neutralization of pickling wastewater with calcium hydroxide in stainless steel pickling process was characterized using X-ray fluorescence spectrometry, X-ray diffractometry, scanning electron microscopy, thermogravimetry and differential scanning calorimetry, etc. The major compositions of pickling sludge are CaF2, CaSO4, Me(OH), (M: Fe, Cr, Ni), and the content of CaF2 is high in the sludge. The melting point of pickling sludge is about 1350℃ and the viscosity is about 0.14 Pa.s at 1450 ℃, which are comparatively lower than those of normal refining slag. After heat treatment, the contents of sulfur and fluorine in the pickling sludge were reduced, confirming the thermal decomposition of sulfate in the sludge. Fluorine in the sludge is reduced by the gaseous SiF4 and A1F3 generated through the reactions of CaF2 with SiO2 and Al2O3. The preliminary results from the reduction test indicate that the sulfur content in the steel is not affected by the presence of sulfur in the sludge. The recovery of nickel is about 40%, and the chromium content changes marginally due to the protective atmosphere under the reduction condition of chromic oxide. The pickling sludge is a potential auxiliary material for the production of stainless steel. 展开更多
关键词 stainless steel pickling sludge CHARACTERIZATION RECYCLING SULFUR FLUORINE
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Use of Fourier-transform infrared spectroscopy to rapidly diagnose gastric endoscopic biopsies 被引量:1
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作者 Qing-BoLi Xue-JunSun +5 位作者 Yi-ZhuangXu Li-MinYang Yuan-FuZhang Shi-FuWeng Jing-SenShi Jin-GuangWu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第25期3842-3845,共4页
AIM: To determine if Fourier-transform infrared (FT-IR)spectroscopy of endoscopic biopsies could accurately diagnose gastritis and malignancy.METHODS: A total of 123 gastroscopic samples, including 11 cases of cancero... AIM: To determine if Fourier-transform infrared (FT-IR)spectroscopy of endoscopic biopsies could accurately diagnose gastritis and malignancy.METHODS: A total of 123 gastroscopic samples, including 11 cases of cancerous tissues, 63 cases of chronic atrophic gastritis tissues, 47 cases of chronic superficial gastritis tissues and 2 cases of normal tissues, were obtained from the First Hospital of Xi'an Jiaotong University, China. A modified attenuated total reflectance (ATR) accessory was linked to a WQD-500 FT-IR spectrometer for spectral measurement followed by submission of the samples for pathologic analysis. The spectral characteristics for different types of gastroscopic tissues were summarized and correlated with the corresponding pathologic results.RESULTS: Distinct differences were observed in the FTIR spectra of normal, atrophic gastritis, superficial gastritis and malignant gastric tissues. The sensitivity of FT-IR for detection of gastric cancer, chronic atrophic gastritis and superficial gastritis was 90.9%, 82.5%, 91.5%, and specificity was 97.3%, 91.7%, 89.5% respectively.CONCLUSION: FT-IR spectroscopy can distinguish gastric inflammation from malignancy. 展开更多
关键词 Fourier-transform infrared spectroscopy Gastric endoscope Gastric cancer Chronic gastritis Spectral analysis Infrared detection
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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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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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Scanning electron microscopy coupled with energydispersive X-ray spectrometry for quick detection of sulfuroxidizing bacteria in environmental water samples 被引量:1
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作者 SUN Chengjun JIANG Fenghua +5 位作者 GAO Wei LI Xiaoyun YU Yanzhen YIN Xiaofei WANG Yong DING Haibing 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期185-191,共7页
Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not mee... Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples. 展开更多
关键词 sulfur bacteria energy-dispersive X-ray spectrometry scanning electron microscopy bacteria detection environmental water samples 16S rRNA sequencing
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Effect of Mg^(2+) content in ion-exchanged Shengli lignite on its equilibrium adsorption water content and its mechanism 被引量:1
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作者 刘祥春 冯莉 +2 位作者 王新华 张营 汤海燕 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第2期456-460,共5页
Mg ion-exchanged samples were prepared with acid-washed Shengli lignite.The chemical composition of the ash of the raw sample was determined by X-ray fluorescence.The equilibrium adsorption water contents of samples w... Mg ion-exchanged samples were prepared with acid-washed Shengli lignite.The chemical composition of the ash of the raw sample was determined by X-ray fluorescence.The equilibrium adsorption water contents of samples were determined in a range of relative humidity.The ion-exchange process was characterized by FT-IR,ash content,and p H value.A possible mechanism is proposed for equilibrium adsorption water of ion-exchanged samples at different humidities.The extent of ion-exchange reaction between Mg2+and lignite is controlled by the concentration of Mg2+in Mg SO4solution.The effect of Mg2+on equilibrium adsorption water content varies with relative humidity and content of Mg2+.The factor that controls equilibrium adsorption water content at low relative humidity is water interactions with sorption sites,which are Mg2+–carboxyl group complex.At middle relative humidity capillary force between Mg2+–water clusters Mg+(H2O)nand capillary is more important.At high relative humidity,free water–free water interactions are more significant. 展开更多
关键词 Ion-exchange FT-IR Equilibrium adsorption water content SURFACE
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Potential Applications of X-ray Fluorescence Core Scanner in Elemental Analyses of the Muddy Sediments on the Coastal Shelves of China and in Ecological Study 被引量:2
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作者 ZHOU Xin SUN Liguang +1 位作者 LIU Yi WANG Yuhong 《Journal of Ocean University of China》 SCIE CAS 2013年第4期619-623,共5页
Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study... Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study on environmental information recorded in mud areas because of complicated sedimentary environment and variable sedimentary rate, requires a fast and economical method. In this study, we investigated the potential of X-ray fluorescence core scanner (XRFS), a fast analytical instrument for measuring the elemental concentrations of muddy sediments, and observed a significant correlation between the element concentrations of muddy sediments determined by regular X-ray fluorescence spectrometer (XRF) and XRFS, respectively. The correlations are mainly determined by excitation energy of elements, but also influenced by solubility of element ions. Furthermore, we found a striking link between A1 concentrations and marine-originated organic carbon (MOC), a proxy of marine primary productivity. This indicates that MOC is partly controlled by sedimentary characteristics. Therefore, XRFS method has a good potential in fast analysis of a large number of muddy sediment samples, and it can also be used to calibrate MOC in ecological study of coastal seas. 展开更多
关键词 X-ray fluorescence core scanner X-ray fluorescence spectrometer muddy sediment marine-originated organic carbon ecological study
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Spectral Method for Three-Dimensional Nonlinear Klein-Gordon Equation by Using Generalized Laguerre and Spherical Harmonic Functions 被引量:3
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作者 Xiao-Yong Zhang Ben-Yu Guo Yu-Jian Jiao 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第1期43-64,共22页
In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve ... In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve the same conservation as that for the exact solution.The stability and convergence of the proposed scheme are proved.Numerical results demonstrate the efficiency of this approach.We also establish some basic results on the generalized Laguerre-spherical harmonic orthogonal approximation,which play an important role in spectral methods for various problems defined on the whole space and unbounded domains with spherical geometry. 展开更多
关键词 Generalized Laguerre-spherical harmonic spectral method Cauchy problem of nonlinear Klein-Gordon equation.
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Carbothermic reduction of alumina with carbon in vacuum 被引量:4
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作者 郁青春 袁海滨 +4 位作者 朱富龙 张晗 王辰 刘大春 杨斌 《Journal of Central South University》 SCIE EI CAS 2012年第7期1813-1816,共4页
Carbothermic reduction alumina in vacuum was conducted, and the products were analysed by means of XRD and gas chromatography. Thermodynamic analysis shows that in vacuum the initial carbothermic reduction reaction te... Carbothermic reduction alumina in vacuum was conducted, and the products were analysed by means of XRD and gas chromatography. Thermodynamic analysis shows that in vacuum the initial carbothermic reduction reaction temperature reduces compared with that under normal pressure, and the preferential order of products is Al404C, Al4C3, Al2OC, Al20 and A1. Experiment results show that the carbothermic reduction products of alumina are A1404C and A14C3, and neither A12OC, Al20 or Al was found. During the carbothermic reduction process, the reaction rate of Al203 and carbon decreases gradually with increasing time. Meanwhile, lower system pressure or higher temperature is beneficial to the carbothermic reduction of alumina process. A1404C is firstly formed in the carbothermic reaction, and then A14C3 is formed in lower system pressure or at higher temperature. 展开更多
关键词 ALUMINA carbothermic reduction VACUUM ALUMINUM
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MHD mixed convective stagnation-point flow of Eyring-Powell nanofluid over stretching cylinder with thermal slip conditions 被引量:1
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作者 Hammed Abiodun OGUNSEYE Precious SIBANDA Hiranmoy MONDAL 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1172-1183,共12页
The optimal design of heating and cooling systems must take into account heat radiation which is a non-linear process.In this study,the mixed convection in a radiative magnetohydrodynamic Eyring-Powell copperwater nan... The optimal design of heating and cooling systems must take into account heat radiation which is a non-linear process.In this study,the mixed convection in a radiative magnetohydrodynamic Eyring-Powell copperwater nanofluid over a stretching cylinder was investigated.The energy balance is modeled,taking into account the non-linear thermal radiation and a thermal slip condition.The effects of the embedded flow parameters on the fluid properties,as well as on the skin friction coefficient and heat transfer rate,are analyzed.Unlike in many existing studies,the recent spectral quasi-linearization method is used to solve the coupled nonlinear boundary-value problem.The computational result shows that increasing the nanoparticle volume fraction,thermal radiation parameter and heat generation parameter enhances temperature profile.We found that the velocity slip parameter and the fluid material parameter enhance the skin friction.A comparison of the current numerical results with existing literature for some limiting cases shows excellent agreement. 展开更多
关键词 Eyring-Powell model stretching cylinder NANOFLUID thermal radiation slip effects spectral quasi-linearization method
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Study on Microcavity Organic Light-emitting Devices Containing Negative Refractive Index Dielectric Layer
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作者 CAI Hong-xin LI Li-xin 《Semiconductor Photonics and Technology》 CAS 2009年第3期153-157,共5页
A new structure containing negative refractive index dielectric layer(NRlDL) is introduced into microcavity. The properties of the new mierocavity organic light-emitting devices(MOLEDs) are investigated. In the ex... A new structure containing negative refractive index dielectric layer(NRlDL) is introduced into microcavity. The properties of the new mierocavity organic light-emitting devices(MOLEDs) are investigated. In the experiment, the transfer matrix method is adopted. The dependence of reflectance and transmittance on the refractive index and thickness of NRIDL are analyzed in detail. Compared with the electroluminescence spectra of non-NRIDL diodes, the line widths of the spectra of the MOLEDs are narrower and all the peaks enhance. The results show that the new structure is beneficial to improve the performance and reduce the thickness of microcavity devices. 展开更多
关键词 microcavity organic light-emitting device electroluminescence(EL) spectra negative refractive index dielectric layer
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Adaptive Spectr um Decision Method for Heterogeneous Cognitive Radio Networks 被引量:4
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作者 Sun Wujian Liu Yang +2 位作者 Li Na Li Ou Li Caiping 《China Communications》 SCIE CSCD 2012年第11期31-40,共10页
To improve spectrum utilization and minimize interference to Primary User (PU), an adaptive spectrum decision method is proposed for Secondary User (SU), while taking traffic load balancing and spectrum heterogeneity ... To improve spectrum utilization and minimize interference to Primary User (PU), an adaptive spectrum decision method is proposed for Secondary User (SU), while taking traffic load balancing and spectrum heterogeneity into consideration. Long-term statistics and current sensing results are integrated into the proposed decision method of spectrum access. Two decision methods, namely probability based and sensing based, are presented, compared and followed by performance analysis in terms of delay. For probability based spectrum decision, Short-Time-Job-First (STJF) priority queuing discipline is employed to minimize average residual time and theoretical conclusion is derived in a novel way. For sensing based decision we treat the interrupted service of SU as newly incoming and re-decision process is initialized to find available spectrum in a First-Available-First-Access (FAFA) fashion. Effect of sensing error in PHY layer is also analyzed in terms of extended average residual time. Simulation results show that, for relatively low arriving rate of SU traffic, the proposed spectrum decision method yields at least a delay reduction of 39.5% compared with non-adaptive method. The proposed spectrum decision can significantly improve delay performance even facing sensing errors, which cause performance degeneration to both PU and SU. 展开更多
关键词 cognitive radio networks spectrum decision probability based decision sensing based decision STJF FAFA sensing error average residual time
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Determination of Ca,K,Mg and Fe in Four Fish Species by FAAS 被引量:8
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作者 CUI Xiaoli WANG Yijun SHE Xilin 《Journal of Ocean University of China》 SCIE CAS 2010年第3期235-238,共4页
A method for determining calcium (Ca), potassium (K), magnesium (Mg) and iron (Fe) in four fish species was opti- mized and validated. It included microwave mineralization of the samples and subsequent quantif... A method for determining calcium (Ca), potassium (K), magnesium (Mg) and iron (Fe) in four fish species was opti- mized and validated. It included microwave mineralization of the samples and subsequent quantification by flame atomic absorption spectroscopy (FAAS) with Zeeman-effect background correction. Using HNO3 (65%) and H202 (33%) as extraction solutions, the optimal conditions of extraction were established as follows: 0.5 g of sample mass; microwave time program of 300 W/5 min and 600 W/5 min. The method was free of matrix interferences. The linear correlation coefficients were ≥0.9991, the recovery percentage of analytes was from 99.31% to 103.70% and the RSD (relative standard deviation) was lower than 2.06%. The detection limits obtained were 32.3, 43.2, 14.0 and 68.6ng mL^-1 for Ca, K, Mg and Fe in FAAS respectively. It is shown that the method is rapid, simple, sensitive and accurate. The method was applied to the studies of digestibility and measurement of these nutrients in samples of fish collected from Norway, Japan and China. 展开更多
关键词 flame atomic absorption spectrometry (FAAS) FISH CALCIUM MAGNESIUM POTASSIUM IRON microwave digestion
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Electron Beam Application for Regeneration of Catalysts Used in Refinery Cracking Units
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作者 Femando Mantovani Kondo Celina Lopes Duarte +2 位作者 Ivone Mulako Sato Vera Lucia Ribeiro Salvador Wilson Aparecido Parejo Calvo 《Journal of Physical Science and Application》 2016年第3期11-19,共9页
A catalyst is a substance that alters the rate of a reaction. The process of catalysis is essential to the modem day manufacturing industry, mainly in FCC (Fluid Catalytic Cracking) process units. However, long-term... A catalyst is a substance that alters the rate of a reaction. The process of catalysis is essential to the modem day manufacturing industry, mainly in FCC (Fluid Catalytic Cracking) process units. However, long-term exploitation of oil and gas processing catalysts leads to formation of carbon- and sulfur-containing structures of coke and dense products on the catalyst surface. They block reactive catalyst sites and reduce the catalytic activity. The main advantage of radiation processing by EB (electron beam) and gamma rays is chain cracking reaction in crude oil. Otherwise, under exposure to ionize radiation, considerable structure modification of equilibrium silica-alumina catalyst from FCC process may occur, in addition to the removal of impurities. The conditions applied in the irradiation range (20-150 kGy) of gamma rays and EB were not sufficient to alter the structure of the catalyst, whether for removal of the contaminant nickel, a major contaminant of the FCC catalyst, either to rupture of the crystalline structure either for the future reutilization of chemical elements. ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and EDXRFS (Energy Dispersive X-Ray Fluorescence Spectrometry) analysis were used to characterize and evaluate effects of radiation processing on equilibrium catalysts purification. To evaluate and comprehend the reactive catalyst sites, SEM (Scanning Electron Microscopy) and particle size distribution analyses were carried out. 展开更多
关键词 EB gamma rays FCC process regeneration of catalysts silica-alumina catalyst.
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Soliton Solutions for Nonisospectral AKNS Equation by Hirota's Method 被引量:1
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作者 BI Jin-Bo SUN Ye-Peng CHEN Deng-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期398-400,共3页
Bilinear form of the nonisospectral AKNS equation is given. The N-soliton solutions are obtained through Hirota's method.
关键词 nonisospectral AKNS equation soliton solutions Hirota's method
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