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Synthesis and Pyrolysis of Soluble Cyclic Hf-Schiff Base Polymers

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Chinese Journal of Polymer Science 2021年第6期39卷 659-664,I0005页

作者： Yu-Huan Wu Li Ye ya-nan sun Wei-Jian Han Tong Zhao Key Laboratory of Science and Technology on High-tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China University ofChinese Academy of Sciences Beijing 100049China

Soluble Hf-containing polymers are significant processable precursors for the fabrication of ultra-high temperature *** this work,cyclic Hf-Schiff base polymers were synthesized via direct polymerization of hafnium alkoxide and bis-salen *** defined structure and molecular weight of the polymers were characterized by NMR spectroscopy,gel permeation chromatography and MALDI-TOF mass *** feed ratio of monomers regulated the molecular weight and solubility of the *** synthetic strategy features simple operation under ambient conditions,efficient reaction with high yield and cyclic polymers as the main *** Hf-Schiff base polymers were converted to HfC/C materials after pyrolysis under argon at 1600°C,which was identified by XRD measurements,elemental analyses and Raman *** work will inspire more precise and efficient synthesis and applications of metallopolymers.

关键词： Hf-containing polymer Schiff base Cyclic polymer Preceramic polymer Hafnium carbide

Yiqi-Liangxue Recipe Improves Recovery of Injured Endothelia by Promoting the Proliferation and Migration of Vascular Endothelial Cells and Balancing Damage-associated in Flammatory Mediators

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World Journal of Traditional Chinese Medicine 2016年第4期2卷 55-61页

作者： Fei Su Xiao-Yun Cui ya-nan sun Qian Lin China-Japan friendship Hospital Dong Fang Hospital Beijing University of Chinese Medicine Medical Experimental Center China Academy of Traditional Chinese Medicine

Aim: Yiqi-Liangxue Recipe(YL) is a compound preparation of Chinese medicine used for preventing cardiovascular events after percutaneous coronary intervention(PCI)(Patent No. 200810240175.4). Maintaining the integrity of endothelia is one of the most effective approaches to prevent restenosis. Given its clinical protective effects on long-term prognosis, we investigated the mechanisms of YL in protecting vascular endothelial ***: We prepared drugs serum and human umbilical vein endothelial cell(HUVEC) lines. The injured model was employed with Angiotensin II(Ang II). The YL group was employed with YL treatment. The ARB medicine group was employed with Losartan Potassium treatment. The combination of Chinese medicine and western medicine(YL+ARB) group was employed with both YL and ARB. The control group was unemployed with injury and medical treatment. For each group the cell migration rate(CM) and cell proliferation rate(CP) were measured. The concentration of Nitric Oxide(NO), Reactive Oxygen Species(ROS), Endothelin-1(ET-1) were assessed. The gene expression level of ET-1 was ***: YL+ARB group significantly promoted the speed of the CM/CP of the injured HUVECs. Compared with model group, the concentration of NO increased after the drug intervention, and the concentration of ET-1 decreased. Compared with YL+ARB group, YL and ARB group each had the similar weaker effects, but did not have significant difference. The fluorescence of ROS in YL, ARB and YL+ARB group had no difference because the fluorescence was too strong. Compared with model group, the-2ΔΔCt values were decreased in the YL, ARB and YL+ARB group. The gene expression level of ET-1 was inhibited after the drug intervention, although with no significant ***: Treatment with YL ameliorates the injury of vascular endothelial cells and YL+ARB has better curative effect. The mechanisms are associated with improving the speed of the CM/CP; increasing the release of NO a

关键词： Yiqi-Liangxue Recipe PCI Vascular endothelial cells Cell migration Damage-associated mediators

Phthalonitrile Resins Derived from Vanillin: Synthesis, Curing Behavior, and Thermal Properties

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Chinese Journal of Polymer Science 2020年第1期38卷 72-83,I0007页

作者： Yue Han Dong-Hao Tang Guang-Xing Wang ya-nan sun Ying Guo Heng Zhou Wen-Feng Qiu Tong Zhao South China Advanced Institute for Soft Matter Science and Technology South China University of Technology Laboratory of Advanced Polymeric Materials Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Sinosteel Anshan Research Institute of Thermo-Energy Co. LTD

Vanillin was used as sustainable source for phthalonitrile monomer synthesis, and allyl/propargyl ether moieties were introduced to improve the processability at the minimal cost of thermal properties. The synthesis route was optimized to minimize side-reactions and simplify post-processing, and the monomers were obtained in high purity and good yields. The curing behavior, mechanism, and processability of the monomers were studied, and the thermal properties of cured polymers were evaluated. Of the two monomers, the allyl ether-containing one exhibited a wide processing window of 185 °C, and was mainly cured into phthalocyanine and linear aliphatic structures through self-catalytic curing process. Also, the glass transition temperature was higher than 500 °C. In contrast, the propargyl ether-containing monomer could only be partially cured, and heat resistance was found to be compromised. Compared with traditional petroleum-based phthalonitrile resins, the biobased monomers could be cured without the addition of catalysts, and improvement in processability was achieved at no cost of thermal performances.

关键词： Allyl ether Curing mechanism Phthalonitrile Thermal properties Vanillin

Analysis on Irrational Decision Making of Tobacco Family Farmers from the Perspective of Optimal Scale of Efficiency

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Asian Agricultural Research 2022年第9期14卷 7-11,15页

作者： ya nan sun Lulu CUI Baohua YU College of Tobacco Henan Agricultural UniversityZhengzhou 450002China College of Economics and Management Henan Agricultural UniversityZhengzhou 450002China

The larger the difference between the willingness scale of tobacco family farmers and the optimal scale of efficiency,the greater the degree of irrationality,and the higher the decision making *** the aid of DEA model,this study calculated the optimal scale of efficiency of Guiyang tobacco family *** the ratio of willingness scale and efficiency optimal scale,it measured the degree of irrationality of family *** addition,with the help of multiple linear regression model,it explained the irrational decision making mechanism of family ***,it made a portrait of farmers who tend to make irrational decisions,to find specific farmers and guide them in their production and operation,reduce the risk of planting scale decision making and stabilize the sustainable development of the tobacco industry.

关键词： Irrational decision making Family farmers Optimal scale of efficiency Portrait

Induction of systemic lupus erythematosus syndrome in BALB/c mice by immunization with active chromatin

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Acta Pharmacologica Sinica 2004年第6期25卷 105-109页

作者： Hong LI, Yun-yi ZHANG, ya-nan sun, Xi-yi HUANG, Yong-feng JIA, Duan LI2 Department of Pharmacology, Schoolof Pharmacy, Fudan University, Shanghai 200032, China Department of Pharmacology School of Pharmacy Fudan University 上海 200032 Department of Pharmacology School of Pharmacy Fudan University Shanghai 200032

AIM: To establish an animal model for systemic lupus erythematosus (SLE)-like syndrome in mice. METHODS: BALB/c mice were immunized with active chromatin isolated from ConA-actived syngeneic spleno-lymphocytes. Plasma samples of mice were tested by enzyme-linked immunosorbent assays (ELISA) for the presence of IgG anti-dsDNA, -ssDNA, and anti-histone antibodies. Tumor necrosis factor-α (TNF-α) in serum was measured by ELISA. Spleno-lymphocyte proliferation assays and the levels of interferon-γ (IFN-γ) in supernatants were tested respectively. Proteinuria was measured. Kidneys were examined by direct immunohistochemical method and light microscopy. RESULTS: Anti-ds DNA, ssDNA, and histone antibodies were induced in active chromatin-immu- nized mice, the proliferation response of splenocytes to ConA and LPS were reduced, levels of interferon-γ in supernatants and TNF-α in serum were lowered. Lupus nephritis was assessed by the presence of Ig deposits, glomerular pathology and proteinuria. CONCLUSION: The active chromatin-induced SLE-like mouse model was similar to idiopathic SLE in human.

关键词： systemic lupus erythematosus chromatin autoantibody tumor necrosis factor interferon type II B-lymphocytes T-lymphocytes female enzyme-linked immunosorbent assay

Photoelectron imaging of resonance-enhanced multiphoton ionization and above-threshold ionization of ammonia molecules in a strong 800-nm laser pulse

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Chinese Physics B 2019年第6期28卷 140-145页

作者： Le-Le Song ya-nan sun yan-Hui Wang Xiao-Chun Wang Lan-Hai He Si-Zuo Luo Wen-Hui Hu Qiu-nan Tong Da-Jun Ding Fu-Chun Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Jilin Institute of Chemical Technology Changchun 132022China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin UniversityChangchun 130012China College of Electronic Science and Engineering State Key Laboratory on Integrated OptoelectronicsJilin UniversityChangchun 130012China

In this work, we mainly investigate the NH3 molecular multiphoton ionization process by using the photoelectron velocity map imaging technique. Under the condition of femtosecond laser(wavelength at 800 nm), the photoelectron images are detected. The channel switching and above-threshold ionization(ATI) effect are also confirmed. The kinetic energy spectrum(KES) and the photoelectron angular distributions(PADs) are obtained through the anti-Abel transformation from the original images, and then three ionization channels are confirmed successfully according to the Freeman resonance effect in a relatively low laser intensity region. In the excitation process, the intermediate resonance Rydberg states are C^1 A 1(6 + 2 photons process), B^1 E(6 + 2 photons process) and C^1 A 1(7 + 2 photons process), respectively. At the same time, we also find that the photoelectron angular distributions are independent of laser intensity. In addition, the electrons produced by different processes interfere with each other and they can produce a spider-like structure. We also find ac-Stark movement according to the Stark-shift-induced resonance effect when the laser intensity is relatively high.

关键词： photoelectron imaging Rydberg state resonance-enhanced multiphoton ionization photoelectron angular distribution

Study on the Cultivation Problems and Strategies for New Professional Tobacco Farmers in China

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Asian Agricultural Research 2023年第12期15卷 16-20页

作者： Yifei ZHANG Jintao WEN Jianyun ZHOU ya nan sun Guiyang Branch of Guizhou Tobacco Company Guiyang 550004China College of Tobacco Henan Agricultural UniversityZhengzhou 450046China

At present,there are still many difficulties in China s tobacco farmers,such as unreasonable age structure,generally low education level,lack of management ability,and low planting *** is necessary to cultivate new professional tobacco *** on the practical problems existing in the cultivation of professional tobacco farmers in China,such as vague screening criteria,lack of pertinence in training content,single training mode,immature evaluation system,insufficient follow-up support and unsystematic cultivation mechanism,this study put forward corresponding strategies and suggestions.

关键词： Tobacco leaves New professional tobacco farmers Cultivation

Identification of Above-Threshold Ionization by Imaging Photoelectrons from Ammonia Molecules in an Intense Femtosecond Laser Field

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Chinese Physics Letters 2022年第2期39卷 28-35页

作者： Qin yang Jing Leng yan-Hui Wang ya-nan sun Hai-Bin Du Dong-Dong Zhang Le-Le Song Lan-Hai He Fu-Chun Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China College of Electronic Science and Engineering State Key Laboratory on Integrated OptoelectronicsJilin UniversityChangchun 130012China Department of Physics No.151 Middle School of ChangchunChangchun 130000China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin UniversityChangchun 130012China Department of Comprehensive Harbin City Vocational CollegeHarbin 150000China Jilin Institute of Chemical Technology Jilin 132022China

The above-threshold ionization process of ammonia molecules induced by a femtosecond laser field at 800 nm is studied in the intensity range from 1.6×10^(13) to 5.7×10^(13)W/cm^(2).Channel switching under different laser intensities is observed and identified in the photoelectron kinetic energy spectra of *** on the photoelectron kinetic energy distributions and the photoelectron angular distributions,the characteristic peaks observed are exclusively assigned to the multiphoton resonance through certain intermediate states,followed by multiphoton above-threshold ionization.

关键词： photoelectron ammonia Ammonia

Photoelectron imaging on vibrational excitation and Rydberg intermediate states in multi-photon ionization process of NH3 molecule

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Chinese Physics B 2020年第9期29卷 274-280页

作者： ya-nan sun yan-Hui Wang Le-Le Song Hai-Bin Du Xiao-Chun Wang Lan-Lai He Si-Zuo Luo Qin yang Jing Leng Fu-Chun Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China College of Electronic Science and Engineering State Key Laboratory on Integrated OptoelectronicsJilin UniversityChangchun 130012China Jilin Institute of Chemical Technology Jilin 132022China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin UniversityChangchun 130012China Department of Comprehensive Harbin City Vocational CollegeHaerbin 150000China

The ionization processes of NH3 molecule are studied by photoelectron velocity map imaging technique in a linearly polarized 400-nm femtosecond laser field. The two-dimensional photoelectron images from ammonia molecules under different laser intensities are obtained. In the slow electron region, the values of kinetic energy of photoelectrons corresponding to peaks 1, 2, 3, and 4 are 0.27, 0.86, 1.16, and 1.6 eV, respectively. With both the kinetic energy and angular distribution of photoelectrons from NH3 molecules, we can confirm that the two-photon excited intermediate Rydberg state is A^1 A2" (v2'=3) state for photoelectron peaks 2, 3, 4, and the three peaks are marked as 1223 (2 + 2), 1123 (2 + 2), and 1023 (2 + 2) multi-photon processes, respectively. Then, peak 1 is found by adding a hexapole between the source chamber and the detection chamber to realize the rotational state selection and beam focusing. Peak 1 is labeled as the 1323 (3 + 1) multi-photon process through the intermediate Rydberg state E^1A1'. The phenomena of channel switching are found in the slow electron kinetic energy distributions. Our calculations and experimental results indicate that the stretching vibrational mode of ammonia molecules varies with channels, while the umbrella vibration does not. In addition, we consider and discuss the ac-Stark effect in a strong laser field. Peaks 5 and 6 are marked as (2 + 2 + 1) and (2 + 2 + 2) above threshold ionization processes in the fast electron region.

关键词： photoelectron velocity map imaging photelectron angular distributions Rydberg state hexapole