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Identification of the Flavone in the Flower Bud of Panax Quinquefolium and Its Content Determination in the Different Parts

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Chemical Research in Chinese Universities 2001年第1期17卷 121-126页

作者： MENG xiang-ying li xiang-gao TIAN Yi-xin liU Yin-yan ZHENG lian-xiu College of Chinese Medical Material Jilin Agricultural UniversityChangchun 130118P.R.China The School of Basic Medical Sciences Norman Bethune University of Medical SciencesChangchun 130021P.R.China People Hospital of Jilin Province Changchun 130021P.R.China

Chemical constituents namely flavonoids in the flower buds of Panax quinque folium were identified and their content was determined in different parts. The content determination was performed using dual wavelength TLC-scan and ultraviolet absorption. Content determination results showed that the content of flavonoid in the flower bud was higher than in the roots.

关键词： Panax quinquefulium Flower buds Flavonoid Root Fruit

Synthesis and Primary Research on Antitumor Activity of Three New Panaxadiol Fatty Acid Esters

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Chemical Research in Chinese Universities 2007年第2期23卷 176-182页

作者： ZHANG Chun-hong li xiang-gao gao Yu-gang ZHANG lian-xue FU Xue-qi Academy of Chinese Traditiorial Medicine Jilin Agricultural University Changchun 130118 P. R. China Edmond H. Fischer Signal Transduction Laboratory College of Life Sciences Jilin University Changchun 130021 P. R. China

For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs, three new fatty acid ester compounds： 3/β-acetoxy panaxadiol （ Ⅰ ）, 3β-palmitic acid aceloxy panaxadiol （ Ⅱ ） , and 3β-octadecanoic acid aceloxy panaxadiol（ Ⅰ , Ⅱ, and m） were synthesized with panaxadiol, diacetyl oxide, palmityl chloride and stearyl chloride, and their structures were determined via MS, ^13C NMR, IR, TLC, and so on. The molar yields of the three compounds are 75.14%, 79. 08%, and 72. 57%, respectively. Meanwhile, the antitumor activity of the three new panaxadiol fatty acid ester derivatives and panaxadiol was compared by using the method of MTT. Tumor cell used was Vero cell line. Positive control was 5-FU, blank was an RPMI1640 culture medium, negative control was an RPMI1640 culture medium and the solvent for drugs to be tested. Compound Ⅰ has the strongest antitumor activity followed by panaxadiol; compounds Ⅱ and Ⅲ have similar and weakest antitumor activities. Furthermore, the antitumor activities of the panaxadiol fatty acid ester derivatives show positive correlation with the concentration of the test group, but show no relationship with the molecular weight of fatty acid. The methods that are used to synthesize the three compounds with high yields and strong antitumor activities are simple and show a great potential for meeting the needs of industrial manufacture of these drugs.

关键词： Synthesis Panaxadiol fatty acid esters Anti-tumor activity

Synthesis and Properties of Novel Luminescent Compounds Containing Triphenylamine and Bipyridine Units

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Chemical Research in Chinese Universities 2012年第2期28卷 313-318页

作者： LU Hai-jun li xiang-gao WANG Shi-rong gao Wen-zheng WANG Sha-sha School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072P.R.China College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018P.R.China

Blue luminescent compounds T1―T4 containing triphenylamine donors,bipyridine acceptors and olefinic linkers were synthesized and characterized by 1 H NMR,13 C NMR and high resolution mass spectrometry（HRMS）.Four compounds T1―T4 exhibit excellent solubility in common solvents and good film forming *** chemical calculations show that compounds T1―T4 have asymmetric linear structures and the proper highest occupied molecular orbital（HOMO） *** UV-Vis absorption and fluorescence emission spectra of the four compounds in dilute chloroform solutions and on the solid films were *** reveals that compounds T1―T4 exhibit similar spectral behavior,suggesting that these compounds can form amorphous state in solid *** calculated absorption and emission spectra of compounds T1―T4 are in good agreement with experimentally determined *** T1―T4 have absolute fluorescence quantum yield above 17% in dilute chloroform *** compounds possess high glass-transition temperature（T g） exceeding 97 ℃ and the maximum T g is 155.28 ℃ for compound *** voltammetry measurements show that these compounds have proper HOMO levels in a range of-5.01―-5.13 eV for hole *** properties of compounds T1―T4 indicate that these compounds are candidates for the application in organic light-emitting devices（OLEDs） as hole-transporting materials（HTMs）.

关键词： Luminescent compound Triphenylamine Bipyridine Hole-transporting material

Absorption Spectrum of a Driven Two-Level Atom in a Tunable Cavity with Injected Squeezed Vacuum

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Chinese Physics Letters 2000年第7期17卷 501-503页

作者： li gao-xiang HUANG Guang-ming PENG Jin-sheng Department of Physics Huazhong Normal UniversityWuhan 430079

The absorption spectrum of a driven two-level atom in a frequency tunable cavity with injected squeezed vacuum is investigated. The line shape of the spectra depends on the relative phase between the driving field and the squeezed vacuum, and the frequency detuning between the driving field and the cavity mode. line narrowing and probe gain can occur and be enhanced by adjusting the phase and detuning.

关键词： vacuum phase absorption

Synthesis and Crystal Structure of 4,4'-(4-(1-Naphthyl)-4-phenyl-1,3-butadienylidene)-bis[N,N-diethylbenzenamine]

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1063-1066页

作者： li xiang-gao WUAn-Shu XU De-Shun WANG Shi-Rong ZHAO Xue-Ming Fine Chemicals Department School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

The title compound （C40H42N2） has been synthesized by the reaction of l-（l- naphthyl）-l-phenyl-3-chloropropylene and bis（4-（diethylamino） phenyl）methanone, and characterized by IR, ^1H NMR, MS and X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 17.047（3）, b = 10.807（2）, c = 18.494（4） A, β = 105.727（4）°, V= 3279.4（11） A^3, Mr = 550.76, Z = 4, Dc = 1.115 g/cm^3,μ（MoKa） = 0.085 mm^-1, F（000） = 1184, the final R = 0.0625 and wR = 0.1384 for 2276 observed reflections （1 〉 2σ（I））. X-ray analysis reveals that the butadiene fragment adopts a planar cisiod conformation and makes a dihedral angel of 69.4（2）° with the naphthalene ring.

关键词： 4,4′-(4-(1-naphthyl)-4-phenyl-1,3-hutadienylidene)bis[N,N-diethyl-benzenamine] synthesis crystal structure

Improved Performance of Fluorinated Copper Phthalocyanine Thin Film Transistors UsingPara-hexaphenyl as the Inducing Layer

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Chinese Physics Letters 2011年第11期28卷 261-263页

作者： MA Feng WANG Shi-Rong li xiang-gao YAN Dong-Hang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022

We demonstrate n-type organic thin film transistors(OTFTs)employing copper hexadecafluorophthalocyanine(CuPcF16)as the active layer and para-hexaphenyl(p-6p)as the inducing *** with the CuPcF16-based OTFTs without the𝑝p-6p inducing layer,the performance of the CuPcF16/𝑝p-6p OTFTs is greatly *** charge carrier field-effect mobilityμ,on-off current ratio𝐼Ⅰon/Ⅰoff and threshold voltage𝑉VT of the CuPcF16/p-6p OTFTs are 0.07 cm^(2)/V・s,1.61×105 and 6.28 V,respectively,approaching the level of a single crystal *** improved performance is attributed to the introduction of𝑝p-6p to form a highly oriented and continuous film of CuPcF16 with the molecularπ–πstack direction parallel to the substrate.

关键词： film approaching phthalocyanine

Population Inversion of a V-type Three-Level Atom due to the Effect of Cavity-Induced Quantum Interference

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Chinese Physics Letters 2001年第1期18卷 48-50页

作者： li gao-xiang PENG Jin-Sheng WU Shao-Ping HUANG Guang-Ming Department of Physics Huazhong Normal UniversityWuhan 430079

A cavity-modified master equation is derived for a coherently driven V-type three-level atom coupled to a singlemode cavity in the bad cavity *** influences of the cavity-induced quantum interference on the steady-state populations are *** show that the population inversion can occur due to the effect of cavity-induced quantum interference.

关键词： quantum Inversion coherent

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang liu xiang li Shen Du Ming gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

Synthesis, Characterization and Properties of Bipolar Triphenylamine Charge Transport Materials

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Chinese Journal of Structural Chemistry 2019年第4期38卷 533-540页

作者： liU Xi-Cheng liU Xin-Yu ZHOU Ping li Jin-Jie TIAN Hao-Ze li xiang-gao School of Chemistry and Chemical Engineering Qufu Normal University School of Chemical Engineering and Technology Tianjin University

Four bipolar triphenylamine(TPA) charge transport materials were constructed by introducing imidazole and trifluoroacetyl groups into the TPA units, and characterized by the nuclear magnetic resonance spectrum(NMR) and mass spectrometry(MS). Among them, 4-(2-(1,3-trifluoroacetyl)imidazole)-phenyl-4,4?-di(4-methoxyphenyl)amine(2 Me OTPA-IOS, 1) was determined by X-ray single-crystal diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 24.338(5), b = 9.565(2), c = 11.456(2) ?, β = 99.427(3)°, Mr = 565.47, V = 2631.0(8) ?3,Z = 4,Dc = 1.428 g/cm3, μ = 0.125 mm–1, F(000) = 1160, the final R = 0.0559 and wR = 0.1265 for 5150 observed reflections with I > 2σ(I). The optimized configurations of the target compounds were obtained by quantum chemical calculation, and the bipolarity of transportable holes and electrons was predicted by the frontier molecular orbital(HOMO and LUMO), which was further confirmed by the time of flight(TOF) method. In addition, the introduction of the terminal flexible chain enhances the solubility, thermal stability(DSC and TGA) and film-forming property of all compounds, and the frontier orbital energy of the solid film of the compounds was also tested(UV-vis and PYS). Thus, these compounds have the bipolarity of transportable holes and electrons and show good solubility and thermal stability.

关键词： triphenylamine(TPA) bipolarity material hole-transport electron-transport