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921.
922.
Zhisheng Wu Guoqing Ouyang Xinyuan Shi Qun Ma Guang Wan Yanjiang Qiao 《Optics and Spectroscopy》2014,117(5):703-709
The previous study mainly focused on the interpretation of the relationship between absorption characteristics and quantitative contribution in each near-infrared (NIR) frequency range. Furthermore, the absorption characteristics of NIR mainly cover overtones and combinations of molecular vibrations such as CH, OH, SH, and NH bonds. And it has been know that NIR wavelengths of C-H bond and O-H bond are assigned to different radio frequencies. This paper was intended to investigate the absorption characteristics of bond C-H and O-H bonds in NIR spectral range. Water and acetone which correspond to O-H and C-H bonds have been selected as typical solvents, as well as solutes. Calibration models were established using partial least square regression (PLS) and multiple linear regression (MLR). The parameter of the model were optimized by different spectral pretreatment methods. The result showed that the model set by Savitzky-Golay smooth (SG) in the spectral region of 810–1100 nm could successfully make accurate predictions. Short wave-NIR region has been discovered as optimum characteristic absorption of C-H and O-H bonds. 相似文献
923.
电能监测系统采用意法(ST)半导体公司STM32F103ZDT6的ARM芯片为核心,以ATT7022C电表芯片对电能参数进行取样,实现电网电压和电流、功率的因数、有功、无功和视在功率等诸多参数的检测,通过W5200A硬件TCP/IP通信芯片进行数据传输,借助乐为物联公司物联网平台,通过网页、博客等方式进行数据发布和管理,参数测量与传输误差在许可范围内,能够投入实际使用;该系统为能耗监测与管理提供了底层硬件平台,提供了数据可靠传输方式,提供了方便、直观的上层管理平台,综合了电能计量与测控、嵌入式系统、物联网、WebServer等多项技术,具有一定的创新性。 相似文献
924.
925.
The Hilbert genus field of the real biquadratic field K=Q(δ~(1/2),d~(1/2)is described by Yue(2010)and Bae and Yue(2011)explicitly in the case=2 or p with p=1 mod 4 a prime and d a squarefree positive integer.In this article,we describe explicitly the Hilbert genus field of the imaginary biquadratic field K=Q(δ~(1/2),d~(1/2)),whereδ=-1,-2 or-p with p=3 mod 4 a prime and d any squarefree integer.This completes the explicit construction of the Hilbert genus field of any biquadratic field which contains an imaginary quadratic subfield of odd class number. 相似文献
926.
一类亚半正定矩阵的左右逆特征值问题 总被引:8,自引:0,他引:8
1.引言在工程技术中常常遇到这样一类逆特征值问题:要求在一个矩阵集合S中,找具有给定的部分右特征对(特征值及相应的特征向量)和给定的部分左特征对(特征值及相应的特征向量)的矩阵.文[2],[3]讨论了S为。x。实矩阵集合的情形.文[4]-[7]对S为nxn实对称矩阵.对称正定矩阵,对称半正定矩阵集合的情形进行了讨论.文【川讨论了S为亚正定阵集合的情形.并提到了对于亚半正定矩阵的情形目下无人涉及,有待进一步研究.本文将对S为nxn亚半正定矩阵集合的情形进行讨论.给出了亚半正定矩阵的左右逆特征值问题有解的充要条件… 相似文献
927.
Liu HuaChang Ouyang HuaFu Peng Jun Huang Tao Gong KeYun Xu TaoGuang Fu ShiNian 《中国科学:物理学 力学 天文学(英文版)》2011,54(2):231-235
The China Spallation Neutron Source (CSNS) front end incorporates a pre-chopper in the Low Energy Beam Transport line (LEBT) that will remove a 530 ns section of beam at approximately 1 MHz rate, which is the RF frequency of the ring at injection. It’s one of the most critical devices for properly controlling the injecting beam loss. Physical designing of the pre-chopper is carried out, and the RFQ itself is used as the beam dump of the chopper system. In order to examine the reliability of the pre-chopper design, the beam study of a similar chopper system is successfully performed. The results of physical design and experiments are presented.
相似文献928.
Hui Ouyang Lvxia Zhang Shan Jiang Wenwen Wang Prof. Chengzhou Zhu Prof. Zhifeng Fu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(34):7583-7588
Co single-atom catalysts (SACs) with good aqueous solubility and abundant labelling functional groups were prepared in Co/Fe bimetallic metal-organic frameworks by a facile solvothermal method without high-temperature calcination. In contrast to traditional chemiluminescence (CL) catalysts, Co SACs accelerated decomposition of H2O2 to produce a large amount of singlet oxygen (1O2) rather than superoxide (O2.−) and hydroxyl radical (OH.). They were found to dramatically enhance the CL emission of the luminol-H2O2 reaction by 1349 times, and, therefore, were employed as very sensitive signal probes for conducting CL immunoassay of cardiac troponin I. The detection limit of the target analyte was as low as 3.3 pg mL−1. It is the first time that employment of SACs for boosting CL reactions has been validated. The Co SACs can also be employed to trace other biorecognition events with high sensitivity. 相似文献
929.
研究了一类分数阶广义非线性扰动热波方程.首先用奇异慑动方法,求出了分数阶广义非线性扰动热波方程初始边值问题的任意次近似解析解.然后利用泛函分析不动点定理证明了它的一致有效性,最后简述了它的物理意义.求得的近似解析解,弥补了单纯用数值方法求模拟解的不足. 相似文献
930.
In this paper, a high-order compact finite difference algorithm is established for the stream function-velocity formulation of the two-dimensional steady incompressible Navier-Stokes equations in general curvilinear coordinates. Different from the previous work, not only the stream function and its first-order partial derivatives but also the second-order mixed partial derivative is treated as unknown variable in this work. Numerical examples, including a test problem with an analytical solution, three types of lid-driven cavity flow problems with unusual shapes and steady flow past a circular cylinder as well as an elliptic cylinder with angle of attack, are solved numerically by the newly proposed scheme. For two types of the lid-driven trapezoidal cavity flow, we provide the detailed data using the fine grid sizes, which can be considered the benchmark solutions. The results obtained prove that the present numerical method has the ability to solve the incompressible flow for complex geometry in engineering applications, especially by using a nonorthogonal coordinate transformation, with high accuracy. 相似文献