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Your search keyword '"Zhao, Yu-Ming"' showing total 338 results
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338 results on '"Zhao, Yu-Ming"'

58. Divergent Total Syntheses of Six Ganoderma Meroterpenoids: A Bioinspired Two-Phase Strategy.

Author

Zhang, Fen and Zhao, Yu-Ming

Subjects
*GANODERMA, *BIOMIMETIC synthesis, *AROMATIZATION, *QUINONE derivatives, *HYDRATION, *PHENOL, *QUINONE
Abstract

We briefly highlight our recent work on the total synthesis of six Ganoderma phenolic meroterpenoids: ganocins A–C, ganocochlearins A–D, and cochlearol T. Critical to this success was a bioinspired two-phase strategy that featured an early-stage rapid construction of a common planar tricyclic intermediate and late-stage highly selective transformations of this intermediate into various Ganoderma meroterpenoids. Key steps of the synthesis include a biomimetic ortho -quinone methide intramolecular hetero-Diels–Alder reaction, a Stahl-type oxidative aromatization, a nucleophilic dearomatization of a phenol, a regioselective 1,4-reduction of a dienone, a site-selective Mukaiyama hydration, and an intramolecular oxa-Michael addition/triflation cascade. [ABSTRACT FROM AUTHOR]

Published
2020
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61. Additional file 1: Table S1. of Neuroprotective effect of a novel Chinese herbal decoction on cultured neurons and cerebral ischemic rats

Author

Ip, Fanny, Zhao, Yu-Ming, Kim-Wan Chan, Cheng, Elaine, Tong, Estella, Oormila Chandrashekar, Guang-Miao Fu, Zhong-Zhen Zhao, and Ip, Nancy

Subjects
cardiovascular diseases
Abstract

Assessments of physiological parameters before, during and after ischemia (MCAO) in control and PSR pre-treated rats. Figure S1. Representative TTC-stained brain slices for sham and MCAO rats, with the latter animals divided into 4 groups that were pre-treated with vehicle, 1.1 g/kg, 2.2 g/kg or 5.5 g/kg PSR. Figure S2. Representative TTC-stained brain slices for sham and MCAO rats, with the latter animals divided into 4 groups that were post-treated with vehicle, 1.1 g/kg, 2.2 g/kg or 5.5 g/kg PSR. (DOCX 3065 kb)

Published
2016
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65. The impulse grounding impedance computation in HVDC transmission line tower

Author

Zhao Yu-ming, Li Tianwei, and Xiang Yang

Subjects
Inductance, Engineering, business.industry, Transmission line, Ground, Equivalent series inductance, Electrical engineering, Electronic engineering, Waveform, Impulse (physics), business, Electrical impedance, Characteristic impedance
Abstract

Electromagnetic field and circuit theory combined is applied to calculate the impulse grounding impedance in HVDC transmission line towers in this paper. The mutual inductance of conductor segments are taken into account. At the same time, the images of the self resistance and mutual inductance are considered for the different medium (soil and air) interface on the surface of the ground. To calculate the impulse grounding impedance, the lightning waveform is transferred to frequency domain by FFT. Through comparison between the results in this paper and the authoritative CDEGS, the theoretical correctness is tested and proved reliable. It will provide theoretical basis for grounding optimal design and type selection, and then improve the reliability of HVDC transmission line operation.

Published
2013

73. Shadow Removal Based on Physical Features and Morphological Methods

Author

Zhao Yu Ming, Zhang Chao, and Liu Shao Jie

Subjects
Shadow and highlight enhancement, Geography, business.industry, Video tracking, Computer vision, Artificial intelligence, business, Luminance
Abstract

In this paper an algorithm has been presented to remove the shadow from images, which includes two steps. First step is to detect shadow regions using physical features of shadow for an initial result with less shadow. Two properties of shadow, luminance and gray density are taken into account, to get the primary result. The second step is based on morphological methods. Using the similarity of gray density and the gradient value, a refined result can be obtained with the help of real edge of the object and the direction to expand.

Published
2013

74. The characteristic components of the rotor broken based on MUSIC method of cross-high-spectrum

Author

Tian Wei and Zhao Yu-ming

Subjects
Engineering, Computational complexity theory, Rotor (electric), business.industry, Stator, Acoustics, Higher-order statistics, Fault (power engineering), law.invention, Noise, law, Component (UML), Electronic engineering, business, Induction motor
Abstract

As Cross high order accumulation is able to depress non-correlative noise and correlative noise, MUSIC method based on cross-high-order cumulate is provided for diagnosing rotor broken-bar. It is difficult to detect faults feature component of the rotor broken-bar that it always hides behind the strong supply frequency component in the spectrum of the stator current. Simulation results were shown that the method is higher in resolution of frequency and more accurate and less in computational complexity. Fault characteristic components can be obtained accurately. The feasibility of the method is confirmed.

Published
2011

77. A Novel Sub-carrier and Power Allocation Algorithm for Multi-user OFDM Systems

Author

Wang Zanji, Guo Jingbo, Zhao Yu-ming, and Xu Yi

Subjects
Computational complexity theory, Computer science, Orthogonal frequency-division multiplexing, ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, Real-time computing, Allocation algorithm, Data_CODINGANDINFORMATIONTHEORY, Computational resource, Multi-user, Computer engineering, Robustness (computer science), Telecommunications link, Bit error rate, Resource management
Abstract

In this paper, a novel sub-carrier and power allocation algorithm for downlink transmission of multi-user OFDM system is presented. The proposed algorithm tries to minimize the total transmission power, while satisfying the bit error rate constraint and rate requirement of each user. The proposed algorithm combines the sub-carriers and power allocation simultaneously, by comparing the power increment to swap the sub-carriers between users. As demonstrated in the simulation results, the proposed algorithm offers better performance than other sub-optimal algorithms, with the similar computational complexity.

Published
2006

78. A robust and recyclable polyurea-encapsulated copper(i) chloride for one-pot ring-opening/Huisgen cycloaddition/CO2 capture in water.

Author

Chen, Yun, Zhang, Wei-Qiang, Yu, Bin-Xun, Zhao, Yu-Ming, Gao, Zi-Wei, Jian, Ya-Jun, and Xu, Li-Wen

Subjects
WATER, COPPER
Abstract

Multicomponent ring-opening/Huisgen cycloaddition reactions combined with CO2 capture with a polyurea-encapsulated copper salt as a catalyst that in situ formed from simple CuCl and soluble polyurea during the reaction were carried out successfully for the synthesis of β-hydroxytriazoles under exceptionally mild conditions, in which the polyurea-encapsulated copper(i) chloride proved to be a robust and recyclable catalyst system with high yields as well as excellent chemoselectivity in this reaction. [ABSTRACT FROM AUTHOR]

Published
2016
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86. Isospin dependence of nuclear multifragmentation in112Sn+112Snand124Sn+124Sncollisions at 40 MeV/nucleon

Author

Lie-Wen Chen, Zhao-Yu Ming, Feng-Shou Zhang, and Zhi-Yuan Zhu

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Isospin, Monte Carlo method, Neutron, Atomic physics, Nucleon, Quantum molecular dynamics, Charged particle
Abstract

Within the framework of an isospin-dependent quantum molecular dynamics model. the multifragmentation in reactions of Sn-112+Sn-112 and Sn-124+Sn-124 at 40 MeV/nucleon is investigated. The calculated results are in good qualitative agreement with the experimental data which indicated that there were significantly different scalings of the mean number of intermediate mass fragments with the number of neutron and charged particles between the two reaction systems. Meanwhile, it is shown that the preequilibrium emission may affect strongly these scalings. [S0556-2813(99)05911-7].

Published
1999

91. Bifunctional Furfuryl Cations Strategy: Three-Component Synthesis of Enamidyl Triazoles.

Author

Yang, Hengtuo, Gou, Jing, Guo, Jiawei, Duan, Dongyu, Zhao, Yu ‐ Ming, Yu, Binxun, and Gao, Ziwei

Subjects
BIFUNCTIONAL catalysis, FURFURYL alcohol, TRIAZOLES synthesis, HETEROCYCLIC compounds synthesis, ORGANIC chemistry
Abstract

A new multicomponent synthesis of functionalized enamidyl triazoles starting from simple and readily available starting materials is described. A simple treatment of a dichloromethane solution of an azide, amine, and 5-bromo-2-furylcarbinol with a Lewis acid provides the enamidyl triazole in good to high yield. A triple domino sequence, formal [3+2] cycloaddition/ring-opening/ amidation, is involved in this new skeleton-generating reaction. [ABSTRACT FROM AUTHOR]

Published
2016
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