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傅玉书父子与《潘氏八世诗集》
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作者 厐思纯 李芳 《贵州文史丛刊》 2017年第4期116-121,共6页
《潘氏八世诗集》是一部艺术价值高、教化功能强的诗歌总集,是贵州明清之际著名的文人家集,是贵州诗史中光彩夺目的篇章。诗集中有不少名宦才人为该集写序跋文,从而增添了含金量。其中傅玉书父子撰写了七篇诗序,实为难得一见的新史料。
关键词 《潘氏八世诗集》 傅玉书父子 傅序
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Fast Digital Correlation Calculation Method in Extended Beacon Wavefront Detection 被引量:1
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作者 陈珂 赵达尊 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期342-348,共7页
On the basis of Hartmann Shack sensor imaging analysis, a new method is presented with which the wavefront slope can be obtained when the object is incoherent and extended. This method, which is demonstrated by both ... On the basis of Hartmann Shack sensor imaging analysis, a new method is presented with which the wavefront slope can be obtained when the object is incoherent and extended. This method, which is demonstrated by both theoretical interpreting and computer simulation, explains how to measure the wavefront slope difference between two sub apertures through the determination of image displacements on detector plane. It includes a fast and accurate digital algorithm for detecting wavefront disturbance, which is much suitable for realization in such electrical hardwares as digital signal processors. 展开更多
关键词 adaptive optics extended beacon wavefront detection fast Fourier transform sequential similarity detection algorithm
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Estimation of structural modal parameters by fourier transform with an optimal window 被引量:1
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作者 朱宏平 万信华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第5期595-598,共4页
An adaptive Fourier Transform (FT) with an optimal window has been proposed for the time-frequency analysis of nonstationary time series. The method allows for a good estimation of both frequency and amplitude of th... An adaptive Fourier Transform (FT) with an optimal window has been proposed for the time-frequency analysis of nonstationary time series. The method allows for a good estimation of both frequency and amplitude of the spectrum and can be easily applied to the general case of time-varying signals. The evaluation of the proposed approach has been performed on measured time-varying signals from a suspension bridge model and a steel frame model whose data have the typical non-stationary characteristics. The numerical results show that the proposed approach can overcome some of the difficulties encountered in the classic Fourier transform technique and can achieve higher computation accuracy. 展开更多
关键词 short-time fourier transform optimal window length modal parameters engineering structures
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Development of Instrument Control System Using Biosignals Created by the Change of Eyes Movement Sequence
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作者 肖云翔 李刚 NOGATA Fumio 《Transactions of Tianjin University》 EI CAS 2003年第2期115-118,共4页
A new biosi gn al control system that offers the disables the opportunities to control electric appliances is proposed.The four types of signals created by the eyes movements in four directions(up,down,left,and right)... A new biosi gn al control system that offers the disables the opportunities to control electric appliances is proposed.The four types of signals created by the eyes movements in four directions(up,down,left,and right),which are taken as four basic signals , are detected at the forehead.Permutation of 2 signals out of them creates 16 d ifferent signals.Permutation of 3 signals out of them creates 64 signals.They al l amounts to 84 control signals.They are thought to be applicable for the operat ion of some instruments.Furthermore,the dynamic biosignals created by the slow e yes movement is speculated to be applicable for the more convenient control of t hem. 展开更多
关键词 eyes movement biosignal control brai n wave visual angle Fast Fourier Transform wavelet coefficient
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Synthesis of ITQ-2 Zeolites and Catalytic Performance in n-Dodecane Cracking
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作者 郝江鸽 王莹 +3 位作者 刘国柱 张靖雯 李国柱 马雪松 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第8期869-874,共6页
ITQ-2 zeolites were prepared by sequential alkali-swelling and ultrasonic-delamination of precursor MCM-22 and characterized by X-ray powder diffraction, scanning electron microscopy, nitrogen adsorption-desorption, a... ITQ-2 zeolites were prepared by sequential alkali-swelling and ultrasonic-delamination of precursor MCM-22 and characterized by X-ray powder diffraction, scanning electron microscopy, nitrogen adsorption-desorption, ammonia temperature-programmed desorption and in-situ Fourier-transform infrared spectroscopy. The delamination induced a change in the morphology of ITQ-2 zeolites from aggregated thin platelets to scattered platelets, together with a significant increase in external specific surface area, which reached a plateau at the ultrasonic treatment time of 3 h. The catalytic cracking of n-dodecane over ITQ-2 zeolites was evaluated with ITQ-2 coated on the inside wall of a tubular reactor at 550 ℃ and 4 MPa. The sample obtained by ultrasonic treatment of 3 h (ITQ-2-3) gave the highest initial conversion of n-dodecane, whereas those of 5 h and I h gave the conversion even lower than MCM-22, which was in agreement with the trend of the ratio of strong Lewis acid to the total acid amount. Although the amount of cokes deposited on ITQ-2-3 was larger than that on MCM-22, the former deactivated slowly, suggesting that a large external specific surface area benefits the stability of zeolite coatings, 展开更多
关键词 MCM-22 zeolite ITQ-2 zeolite SWELLING DELAMINATION Catalytic cracking N-DODECANE
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The HAUSDORFF DIMENSION AND MEASURE OF THE GENERALIZED MORAN FRACTALS AND FOURIER SERIES
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作者 REN FUThO LIANG JINRONG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第2期153-162,共10页
This paper studies the Hausdorff dimensions, the Hausdorff measures of generalized Moranfrontals and the convergence of the Fourier series of functions defined on some generalizedMoran fractals. A general formula is g... This paper studies the Hausdorff dimensions, the Hausdorff measures of generalized Moranfrontals and the convergence of the Fourier series of functions defined on some generalizedMoran fractals. A general formula is given for the calculatinn of the Hausdorff dimensions ofgeneralized Moran fractals and it is proved that their Hausdorff measures are finite positivenumbers under some conditions. In addition, the authors define an orthonormal system offunctions defilled on generalized Moran s-sets (gMs) and discuss the convergence of the Fourierseries, with respect to of each function f(x) E L1(gMs, Hs). 展开更多
关键词 Haudorff dimension Hausdorff measure s-set Differentiation base Fourier series.
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Easily prepared and stable functionalized magnetic ordered mesoporous silica for efficient uranium extraction 被引量:3
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作者 Wenlu Guo Changming Nie +6 位作者 Lin Wang Zijie Li Lin Zhu Liuzheng Zhu Zhentai Zhu Weiqun Shi Liyong Yuan 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第5期629-636,共8页
Functionalized magnetic Fe_3O_4@SiO_2 composite nanoparticles were prepared by simply embedding iron oxide nanoparticles into MCM-41 through one-step synthesis process, followed by aminopropyls grafting on the mesopor... Functionalized magnetic Fe_3O_4@SiO_2 composite nanoparticles were prepared by simply embedding iron oxide nanoparticles into MCM-41 through one-step synthesis process, followed by aminopropyls grafting on the mesopore channels, aiming to efficiently and conveniently uptake U(VI) from aqueous solution. The resultant material possesses highly ordered mesoporous structure with large surface area, uniform pore size, excellent thermal stability, quick magnetic response, and desirable acids resistance, confirmed by Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM), N_2 adsorption/desorption experiments, powder X-ray diffraction(PXRD), and thermogravimetric analysis(TGA). Detailed U(VI) sorption test indicated that this material is indeed an effective U(VI) sorbent with fast sorption kinetics of less than 2 h, large sorption capacity of 160 mg/g at p H 5.0±0.1, and desirable selectivity towards U(VI) ions over a range of competing metal ions. The absorbed U(VI) can be easily desorbed by 0.01 mol/L or more concentrated HNO_3 solution, and the reclaimed sorbent can be reused with no obvious decrease of sorption capacity even after 4 sorption-desorption cycles. The present results suggest the vast opportunities of this kind of magnetic composite on the solid-phase extraction of U(VI). 展开更多
关键词 aminopropyls MAGNETIC ordered mesoporous silica URANIUM SORPTION
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On temporal-spatial distribution of backscatter coefficients over China determined by TOPEX/Poseidon mission 被引量:6
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作者 GUO JinYun YANG Lei +2 位作者 LIU Xin HWANG CheinWay YANG Hong 《Science China Earth Sciences》 SCIE EI CAS 2012年第12期2068-2083,共16页
This paper deals with the backscatter coefficients known as sigma0 at Ku band and C band based on the GDR-M (Merged Geophysical Data Record) of TOPEX/Poseidon (T/P) through Jan.1993 to Dec.2004 over land surface of Ch... This paper deals with the backscatter coefficients known as sigma0 at Ku band and C band based on the GDR-M (Merged Geophysical Data Record) of TOPEX/Poseidon (T/P) through Jan.1993 to Dec.2004 over land surface of China.After smoothing and interpolating the backscatter coefficients for both bands, we achieve the 5′×5′ grid data and the time series of backscatter coefficients in 12 years.The spatial distribution of sigma0 over typical areas (wetland, desert, mountainous area, agriculture base, etc.) of Chinese territory is analyzed and discussed.The fast Fourier transformation (FFT) is used to detect the cycles of seasonal variations of sigma0 time series and gives that the annual period is the major cycle.Meanwhile a semiannual period is also found in some places.We use the least squares method on both periods and find that the amplitude of annual period is obviously greater than that of semi-annual period.The relationship among the anomalousness of time series, variations of environment and climate change, and the serious natural calamity (flood, drought) is also discussed.Data of topography slope extracted from SRTM are used to do correlation analysis with the backscatter coefficients in parts of China to quantify the impact of slope on backscatter coefficients in Ku and C bands, and the results show that they all have a negative correlation but the magnitudes are different in different places with different coverages.Such as the area of Liaoning and Jilin has the maximum correlation -0.56, the Taklimakan Desert has the minimum correlation -0.11, and the other places commonly have correlations in (-0.3, -0.5). 展开更多
关键词 backscatter coefficient satellite altimetry TOPEX/POSEIDON land surface SRTM
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New synthetic procedure for Na NH_2(BH_3)_2 and evaluation of its hydrogen storage properties 被引量:1
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作者 Weidong Chen Zhenguo Huang +1 位作者 Guotao Wu Ping Chen 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第1期169-173,共5页
Tremendous efforts have been devoted to the synthesis of new light element hydrides for hydrogen storage. Ammonia borane (AB) is a promising candidate possessing high hydrogen capacity and low dehydrogenation temper... Tremendous efforts have been devoted to the synthesis of new light element hydrides for hydrogen storage. Ammonia borane (AB) is a promising candidate possessing high hydrogen capacity and low dehydrogenation temperature. The step-wise dehydrogenation and release of by-products, however, are obstacles to its practical application. Chemical modifications of AB to synthesize new compounds or its derivatives are of practical and fundamental importance. Here we report an improved synthesis of sodium aminodiborane (NaNH2(BH3)2, NaABB), a derivative of ammonia borane. This procedure leads to high purity NaABB by reacting NaNH2 and 2 eq. AB. The dehydrogenation properties have been investigated by means of temperature programmed desorption-mass spectrometry, volumetric release, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and X-ray diffraction. In a closed vessel, NaABB can release -2 eq. H2 when heated at 271 ℃, forming solid products of NaBH4 and highly condensed polyborazylene. 展开更多
关键词 ammonia borane aminodiborane DEHYDROGENATION hydrogen storage
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