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991.
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
992.
993.
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
994.
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995.
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
996.
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
997.
Xinyi Wang Xijun Xu Prof. Jun Liu Zhengbo Liu Jiadong Shen Fangkun Li Prof. Renzong Hu Prof. Lichun Yang Prof. Liuzhang Ouyang Prof. Min Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(49):11486-11493
As anode materials for high-performance Li-ion batteries, peapod-like Ge-based composites, including Ge, a Li-inactive conducting Cu3Ge, and a porous carbon matrix are synthesized simply by annealing CuGeO3@dopamine in a H2/Ar atmosphere. The introduction of the carbon layer and inactive alloying phase Cu3Ge not only enhances the electrical conductivity of the Ge anode, but also reduces the volume change of Ge during the cell cycle as a buffer. In particular, the anode of this peapod-like Cu3Ge/Ge@C shows an excellent long cycle life as well as outstanding capacity performance, with a discharge specific capacity up to 934 mA h g−1 after 500 cycles. 相似文献
998.
999.
Pu Fan Alfaro Clint M. Pirro Valentina Xie Zhuoer Ouyang Zheng Cooks R. Graham 《Analytical and bioanalytical chemistry》2019,411(8):1503-1508
Analytical and Bioanalytical Chemistry - Isocitrate dehydrogenase (IDH) I and II mutations in gliomas cause an abnormal accumulation of 2-hydroxyglutarate (2-HG) in these tumor cells. These... 相似文献
1000.