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81.
In this paper we described how different line coding techniques vary with values of jitter in soliton transmission system. Then the idea of this soliton transmission system is applied for multiuser structure and effects of initial line phase spacing are examined.  相似文献   
82.
In this article, we study the interactions of delta shock waves for the one-dimensional Euler equations for Chaplygin gas with split delta functions. We constructively obtain the solutions when the initial data are three piecewise constant states. The global structure and large time-asymptotic behaviors of the solutions are analyzed case by case. Moreover, we obtain the stability of solutions by letting perturbed parameter ? tend to zero.  相似文献   
83.
基于由同心环状排布的多个 PIN 探测器组成的环状 PIN 阵列,发展了一种测量激光等离子体全口径背向散射光空间分布的实验方法.采用该方法,在神光Ⅱ装置激光与黑腔靶相互作用实验中,对全口径背向散射光空间分布进行了测量,获得了全口径受激 Brillouin 散射背向散射光空间分布的图像.初步建立了全口径背向散射光空间分布...  相似文献   
84.
Suppose F is a field of characteristic not 2. Let MnF and SnF be the n × n full matrix space and symmetric matrix space over F, respectively. All additive maps from SnF to SnF (respectively, MnF) preserving Moore-Penrose inverses of matrices are characterized. We first characterize all additive Moore-Penrose inverse preserving maps from SnF to MnF, and thereby, all additive Moore-Penrose inverse preserving maps from SnF to itself are characterized by restricting the range of these additive maps into the symmetric matrix space.  相似文献   
85.
In this paper a digital in-line holographic recording and reconstruction system was set up and used in the particle image velocimetry for the 3Dt-3c (the three-component (3c), velocity vector field measurements in a three-dimensional (3D), space field with time history (t)) flow measurements that made up of the new full-flow field experimental technique—digital holographic particle image velocimetry (DHPIV). The traditional holographic film was replaced by a CCD chip that records instantaneously the interference fringes directly without the darkroom processing, and the virtual image slices in different positions were reconstructed by computation using Fresnel–Kirchhoff integral method from the digital holographic image. Also a complex field signal filter (analyzing image calculated by its intensity and phase from real and image parts in fast fourier transform (FFT)) was applied in image reconstruction to achieve the thin focus depth of image field that has a strong effect with the vertical velocity component resolution. Using the frame-straddle CCD device techniques, the 3c velocity vector was computed by 3D cross-correlation through space interrogation block matching through the reconstructed image slices with the digital complex field signal filter. Then the 3D-3c-velocity field (about 20 000 vectors), 3D-streamline and 3D-vorticiry fields, and the time evolution movies (30 field/s) for the 3Dt-3c flows were displayed by the experimental measurement using this DHPIV method and techniques.  相似文献   
86.
《光谱实验室》投稿须知(2002)   总被引:1,自引:1,他引:0  
《光谱实验室》是中国科学院主管,中国科学院化工冶金研究所等单位联合主办,科学出版社出版的中国科学核心期刊之一,是自主经营,自负盈亏的刊物,编委要有献身本专业科技出版事业的精神,来稿必须符合国家关于出版物的政治和技术标准,出版正常周期为2-6个月,“保质,高效”是本刊的主要特色。  相似文献   
87.
Organic electrode materials have application potential in lithium batteries owing to their high capacity, abundant resources, and structural designability. However, most reported organic cathodes are at oxidized states (namely unlithiated compounds) and thus need to couple with Li-rich anodes. In contrast, lithiated organic cathode materials could act as a Li reservoir and match with Li-free anodes such as graphite, showing great promise for practical full-battery applications. Here we summarize the synthesis, stability, and battery applications of lithiated organic cathode materials, including synthetic methods, stability against O2 and H2O in air, and strategies to improve comprehensive electrochemical performance. Future research should be focused on new redox chemistries and the construction of full batteries with lithiated organic cathodes and commercial anodes under practical conditions. This Minireview will encourage more efforts on lithiated organic cathode materials and finally promote their commercialization.  相似文献   
88.
研发的油田设备管理系统软件可完成设备的静态信息管理、设备动态信息管理、设备运行统计分析和设备维护等功能;系统以Eclipse作为开发平台,以Spring框架为开发模式,使用JSP进行具体开发工作,数据库使用企业级的Oracle数据库,通过Hibernate框架访问数据库,可以将实现业务逻辑的代码和数据库访问代码有效分开,使程序结构更加清晰,减少了软件维护的难度;文章详细介绍了软件的主要功能模块和系统的关键技术;该系统已经部署于油田现场,实现了对智能远程终端设备的初步的全生命周期管理,保障设备的安全运行。  相似文献   
89.
Although liquid chromatography with mass spectrometry in full scan mode can obtain all the signals simultaneously in a large range and low cost, it is rarely used in quantitative analysis due to several problems such as chromatographic drifts and peak overlap. In this paper, we propose a Tchebichef moment method for the simultaneous quantitative analysis of three active compounds in Qingrejiedu oral liquid based on three‐dimensional spectra in full scan mode of liquid chromatography with mass spectrometry. After the Tchebichef moments were calculated directly from the spectra, the quantitative linear models for three active compounds were established by stepwise regression. All the correlation coefficients were more than 0.9978. The limits of detection and limits of quantitation were less than 0.11 and 0.49 μg/mL, respectively. The intra‐ and interday precisions were less than 6.54 and 9.47%, while the recovery ranged from 102.56 to 112.15%. Owing to the advantages of multi‐resolution and inherent invariance properties, Tchebichef moments could provide favorable results even in the situation of peaks shifting and overlapping, unknown interferences and noise signals, so it could be applied to the analysis of three‐dimensional spectra in full scan mode of liquid chromatography with mass spectrometry.  相似文献   
90.
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