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Synthesis, luminescence properties and energy transfer of binary and ternary rare earth complexes with aromatic acids and 1,10-phenanthroline

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Chinese Journal of Chemistry 1997年第3期15卷 242-249页

作者： yan, b Zhang, HJ Ni, JZ Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

A series of binary and ternary rare earth (Gd, Eu, Tb) complexes with ortho hydroxyl benzoic acid, pam aminobenzoic acid, nicotinic acid and 1,10-phenanthroline were synthesized. Phosphorescence spectra and lifetimes of Gd complexes were measured and the lowest triplet state energies of gadolinium binary complexes end the intramolecular energy transfer efficiencies were determined. The luminescence properties and energy transfer process of Eu3+ and Tb3+ complexes were discussed.

关键词： luminescence energy transfer rare earth complexes energy match

The Synthesis, Luminescence and Energy Transfer of the binary and Ternary Complexes of Rare Earth with Aminobenzoic Acids and 1,10-Phenanthroline

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Chinese Chemical Letters 1997年第4期8卷 353-356页

作者： yan, b Zhang, HJ Ni, JZ CHINESE ACAD SCI CHANGCHUN INST APPL CHEMLAB RARE EARTH CHEMCHANGCHUN 130022PEOPLES R CHINA

Thirteen kinds of binary and ternary complexes of rare earth (Gd, Eu,Tb) with ortho (para) aminobenzoic acid and 1.10--phenanthroline were synthesized and characterized. The phosphorescence spectra and lifetimes of gadolinium complexes were measured and the lowest triplet state energies of ligands and the energy transfer efficiencies between ligands were determined. The luminescence properties and intramolecular energy transfer of these complexes were studied in details.

关键词： AbA Luminescence and Energy Transfer of the binary and Ternary Complexes of Rare Earth with Aminobenzoic Acids and 1,10-Phenanthroline The Synthesis

Luminescence Properties of the Ternary Terbium Complexes with (Ortho and Para) Aminobenzoic acids and 1,10-Phenanthroline Incorporated in Silica Matrix by a Sol-gel Method

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Chinese Chemical Letters 1997年第7期8卷 633-636页

作者： yan, b Zhang, HJ Wang, Sb Ni, JZ CHINESE ACAD SCI CHANGCHUN INST APPL CHEMLAB RARE EARTH CHEM & PHYSCHANGCHUN 130022PEOPLES R CHINA

Ternary complexes of terbium with ortho (and pam) aminobenzoic acid and 1,10-phenanthroline were introduced into silica gel by the sol-gel method. The luminescence behavior of the solid-state samples was studied durin... 详细信息

关键词： AbA Luminescence Properties of the Ternary Terbium Complexes with Aminobenzoic acids and 1,10-Phenanthroline Incorporated in Silica Matrix by a Sol-gel Method Ortho and Para

A stabilized complementarity formulation for nonlinear analysis of 3D bimodular materials

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Acta Mechanica Sinica 2016年第3期32卷 481-490页

作者： L.Zhang H.W.Zhang J.Wu b.yan Department of Engineering Mechanics College of AerospaceEngineering Chongqing University State Key Laboratory of Structural Analysis for IndustrialEquipment Dalian University of Technology

bi-modulus materials with different mechanical responses in tension and compression are often found in civil,composite, and biological engineering. Numerical analysis of bimodular materials is strongly nonlinear and convergence is usually a problem for traditional iterative schemes. This paper aims to develop a stabilized computational method for nonlinear analysis of 3D bimodular materials. based on the parametric variational principle, a unified constitutive equation of 3D bimodular materials is proposed, which allows the eight principal stress states to be indicated by three parametric variables introduced in the principal stress *** original problem is transformed into a standard linear complementarity problem（LCP） by the parametric virtual work principle and a quadratic programming algorithm is developed by solving the LCP with the classic Lemke＇s algorithm. Update of elasticity and stiffness matrices is avoided and, thus, the proposed algorithm shows an excellent convergence behavior compared with traditional iterative *** examples show that the proposed method is valid and can accurately analyze mechanical responses of 3D bimodular materials. Also, stability of the algorithm is greatly improved.

关键词： bimodular materials Non-smooth stressstrain relationship Parametric variational principle Complementarity

Laser powder b e d fusion of copper matrix iron particle reinforced nanocomposite with high strength and high conductivity

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Journal of Materials Science & Technology 2023年第3期134卷 50-59页

作者： Yingang Liu Jingqi Zhang Qiang Sun Meng Li Ming yan b Xing Cheng Miaoquan Li Ming-Xing Zhang School of Mechanical and Mining Engineering The University of QueenslandSt.LuciaQLD 4072Australia Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-performance Materials Southern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China

Liquid-liquid phase separation,and the resulted solute segregation,during conventional solidification have been a long-term challenge to produce copper(Cu)-iron(Fe)immiscible composites with high strength and high *** present work reports an effective solution to this issue through laser powder bed fusion(L-PbF)in-situ alloying of Cu-8 wt.%*** observation showed that the fast cooling within micron-scale melt pools fully eliminated the Fe segregation and therefore the L-PbF fabricated nanocomposite achieved the homogeneous microstructure,which featured equiaxed fine grains around 1μm in *** of the nanocomposite at 600℃for 1 h enabled precipitation of two types of *** is coarser Fe nanoprecipitates with body-centered cubic(bCC)structure and diam-eter of 100-300 nm,mainly distributing along grain *** other is smaller Fe nanoprecipitates with face-centered cubic(FCC)structure and diameter of 10-35 nm,being observed within the grains and having coherent interfaces with the Cu *** a result,the aged Cu-Fe nanocomposite achieved tensile strength of 462.9±6.6 MPa with 30.4%±1.7%elongation to failure and 74.5%IACS(International Annealed Copper Standard)electrical *** formation mechanisms of the nanoprecipitates and the strengthening mechanisms of the nanocomposite are discussed.

关键词： Immiscible alloy Copper Laser powder bed fusion Ageing Nanocomposite

Standardization and Identification of Minor Components of Silymarin (MK-001)

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Chinese Herbal Medicines 2012年第3期4卷 237-244页

作者： yan-ze LIU[a][b] David Yue-wei LEE[a] bioorganic and Natural Product Laboratory McLean Hospital/Harvard Medical SchoolMA 02478USA Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China

Objective To develop a highly effective HPLC method for standardization of silymarin and for characterization of minor components, which has not been reported previously. Methods An HPLC fingerprinting method and 1 H-NMR spectroscopy were employed to provide assurance for a standardized silymarin product (MK-001). Results A total of 18 marker compounds were identified and characterized including ten flavonolignans and eight small molecules including adenine, adenosine, uridine, and 3,5,7-trihydroxychromone which were first isolated and characterized from silymarin. The HPLC fingerprinting method and 1 H-NMR had been established for complete assignments of HPLC peaks with intensity over 1.0%. Conclusion The successfully established HPLC fingerprinting method and 1 H-NMR could be applied for the standardization of commercial silymarin products. MK-001 represents the first standardized silymarin with the highest content of flavonolignans ( > 90%).

关键词： adenine flavonolignans 1 H-NMR HPLC fingerprinting silymarin

Intermetallics and phase transformations of the Zr-1.0Sn-0.3Nb-0.3Fe-0.1Cr alloy

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Rare Metals 2008年第5期27卷 468-472页

作者： LIANG Jianlie TANG Yiyuan NONG Liangqin yan Jialin ZHUANG Yinghong Key Laboratory of the Ministry of Education of China for Nonferrous Metals and New Processing Technology of Materials Guangxi University Nanning 530004 China School of Physics and Electronic Engineering Guangxi University for Nationalities Nanning 530006 China Institute of Materials Sciences Guangxi University Nanning 530004 China

Intermetallics and phase transformations of the zirconium-based alloy, Zr-1.0Sn-0.3Nb-0.3Fe-0.1Cr, were investigated by conventional X-ray diffraction （XRD）, differential scanning calorimetry （DSC）, and dilation measurement. Three types of precipitates, namely, （ZrNb）2Fe, Zr（CrFe）2, and Zr3Fe, were detected by XRD. The cubic Ti2Ni-type （ZrNb）2Fe was found to be the main precipitate in the alloy, and it was proposed to dissolve at 861℃, whereas Zr3Fe dissolved at 780℃ and Zr（CrFe）2 at 814℃. No precipitates were observed at a temperature higher than 900℃. The transformation-start temperature of α-Zr → β-Zr was reconfirmed to be 780℃, and the end temperature of α-Zr →βZr was determined to be 955℃. The dilation result also revealed that the martensitic transformation-start temperature, Ms, and the finish temperature, Mf, of this alloy were 741℃ and 645℃, respectively.

关键词： phase transformation intermetallics X-ray diffraction zirconium-based alloy

Effects of Total Alkaloids in buxus microphylla Leaves on Aorta Smooth Muscle of Rats and Their Mechanisms

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Chinese Herbal Medicines 2012年第2期4卷 136-141页

作者： Hui-qin ZHANG[a] yan-yan LIU[b] Yong-wen LI[a] Li LI[a] Zhi-qing CUI[c] Department of Pharmacology Guilin Medical College Guilin 541001 China

Objective To investigate the effects of total alkaloids in buxus microphylla leaves(AbML)on isolated rats thoracic aorta rings,and then to explore the possible mechanisms underlying the *** Thoracic aortas of Wistar rats were isolated,removed,and mounted onto an organ *** effects of AbML at different concentration on the contraction of isolated thoracic aorta rings(with and without endothelium)precontracted with KCl or PE were observed with organ bath ***-effect curves of CaCl2 were recorded by organ bath *** concentration of intracellular Ca 2+ ([Ca 2+ ]i)increased by PE,KCI,and caffeine in the presence of AbML was determined using Ca 2+ sensitive fluorescence indicator Fura-2/AM loaded thoracic aorta vascular smooth muscle (VSM)cells of *** In aorta rings precontracted with PE and KCl,AbML produced concentration- dependent relaxation in both intact and denuded endothelium ring *** was no difference in the inhibition of contraction between the intact and denuded endothelium ring groups at the same *** of isolated thoracic aorta rings to AbML led to a significant reduction in the contracting response induced by CaCl2,and shifted the cumulative concentration-response curves to *** could significantly inhibit the extracellular Ca 2+ influx induced by PE and KCl under[Ca 2+ ]0 of 1.5 mmol/L,with inhibitory ratios of 40.2%and 49.9%,*** the case of Ca 2+ -free,AbML could significantly inhibit the intracellular Ca 2+ release induced by PE,with inhibitory ratio of 72.4%.Conclusion AbML relaxes thoracic aorta VSM cells by suppressing influx of extracellular Ca 2+ via voltage-dependent Ca 2+ channel and receptor-operated Ca 2+ channel.

关键词： Ca 2+ Fura-2/AM isolated thoracic aorta rings total alkaloids of buxus microphylla leaves vascular smooth muscle cells

Temperature enhancement induced by ionosphere heating in low altitude region

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Progress in Natural Science:Materials International 2008年第11期18卷 1339-1343页

作者： bin Xu~(a,*) Jian Wu~b Zhensen Wu~a Jun Wu~b Haiqin Che~b Yubo yan~b Kun Xue a School of Science Xidian University,Xi’an 710071,China b National Key Laboratory of Electromagnetic Environment,China Research Institute of Radiowave Propagation,beijing 102206,China School of Science Xidian University Xi’an 710071 China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave Propagation Beijing 102206 China

The assumption that the electron temperature is approximately equal to the ion temperature is not rational during the high frequency (HF)heating in low ionosphere ***,using the theoretical formula of incoherent scatter spectra with collisional plasma,the incoherent scatter data are analyzed during ionosphere heating at 91.7 km height on August 15th *** enhancements of electron temperature are obtained,and the incremental percent is up to 37% and 46% at the universal time of 10:22 and 10:30,*** using the same initialization value,the ionosphere heating process is simulated by Ohmic theory and the experimental results are basically consistent with the simulation.

关键词： Incoherent scatter spectra Ohmic theory Ionospheric heating Electron temperature