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Chinese Chemical Letters 1997年第11期8卷 985-988页

作者： yi Yang dong Ai Jin HUANG yi Liang SUN(Department of Chemistry Peking University Beijing 100871) Beijing Univ Dept Chem Beijing 100871 Peoples R China

Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom in capillary zone electrophoresis. The reason is due to the reduction of the average apparent mobilities of the analytes.

关键词： Enhancement of Selectivity in Capillary Zone Electrophoresis by Adding Ethanolamines or Ethylamines in the Running Buffer

Reprocessible Epoxy Networks with Tunable Physical Properties:Synthesis,Stress Relaxation and Recyclability

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Chinese Journal of Polymer Science 2018年第5期36卷 641-648页

作者： Jia-Hui Chen Xu-Pei An yi-dong Li Ming Wang Jian-Bing Zeng School of Chemistry and Chemical Engineering Southwest University

In order to extend the application of epoxy vitrimer, 1,4-cyclohexanedicarboxylic acid（CHDA） was used as a co-curing agent and structure modifier for sebacic acid（SA） cured diglycidyl ether of bisphenol A（DGEBA） epoxy vitrimer to tailor the mechanical properties of epoxy vitrimers with 1,5,7-triazabicylo[4.4.0]dec-5-ene（TBD） as a transesterification catalyst. The glass transition temperature（Tg） of vitrimer increased gradually with the increase in CHDA content. Vitrimers behaved from elastomer to tough and hard plastics were successfully achieved by varying the feed ratio of CHDA to SA. Both the Young＇s modulus and storage modulus increased apparently with the increase in CHDA content. Stress relaxation measurement indicated that more prominent stress relaxation occurred at elevated temperatures and the stress relaxation decreased with the increase of CHDA content due to the reduced mobility of the vitrimer backbone. The vitrimers showed excellent recyclability as evidenced by the unchanged gel fraction and mechanical properties after compression molded for several times. With tunable mechanical properties, the epoxy vitrimers may find extensive potential applications.

关键词： Epoxy vitrimer Mechanical properties Stress-relaxation Recyclability

Evolution of surfaces and mechanisms of contact electrification between metals and polymers

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Chinese Physics B 2022年第6期31卷 572-579页

作者： Lin-Feng Wang yi dong Min-Hao Hu Jing Tao Jin Li Zhen-dong Dai Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Contact electrification(CE)is a pretty common phenomenon,but still is poorly *** long-standing controversy over the mechanisms of CE related to polymers is particularly intense due to their *** this paper,the CE between metals and polymers is systematically studied,which shows the evolution of surfaces is accompanied by variations of CE *** variations of CE charge quantity are closely related to the creep and deformation of the polymer and metal *** the relationship between CE and polymer structures is put forward,which is essentially determined by the electronegativity of elements and the functional groups in the *** effects of load and contact frequency on the CE process and outputs are also investigated,indicating the increase of CE charge quantity with load and *** transfer from polymer to metal is observed during CE while electrons transfer from metal to polymer,both of which are believed to have an influence on each *** findings advance our understanding of the mechanism of CE between metal and polymers,and provides insights into the performance of CE-based application in various conditions,which sheds light on the design and optimization of CE-based energy harvest and self-powered sensing devices.

关键词： contact electrification surface evolution material structures material transfer

Host-induced silencing of MpPar6 confers Myzus persicae resistance in transgenic rape plants

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Journal of Integrative Agriculture 2024年第1期23卷 187-194页

作者： Qi Zhang Wenqin Zhan Chao Li Ling Chang yi dong Jiang Zhang State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life SciencesHubei UniversityWuhan 430062China Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhan 430062China Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518000China

Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect *** green peach aphid,Myzus persicae,feeds on over 400 species of host *** napus(rape)is the second most important oilseed crop *** persicae is highly reproductive and causes severe damage to the rape plants due to its quite flexible life *** this study,we tested the RNAi effects of transgenic rape plants on *** in vitro feeding *** with artificial diets containing double-stranded RNAs(dsRNAs)targeting seven aphid genes,we identified a new gene encoding the partitioning-defective protein 6(Par6)as the most potent RNAi ***-and stage-expression analysis of Par6 suggested this gene is highly expressed in the embryo and adult stage of *** next generated transgenic rape plants expressing ds Par6 by Agrobacteriummediated transformation and obtained nine independent transgenic *** to wild-type control plants,transgenic rape lines expressing ds Par6 showed strong resistance to *** assays revealed that feeding transgenic rape plants to *** significantly decreased MpPar6 expression and survival rate and impaired ***,we showed that the resistance levels to *** are positively correlated with ds Par6 expression levels in transgenic rape *** study demonstrates that transgenic rape plants expressing ds Par6 are efficiently protected from *** with the genes involved in embryo development could be the effective RNAi targets for controlling aphids and potentially other insect pests.

关键词： oilseed rape pest control aphid double-stranded RNA RNA interference

Modelling of the Self Sum-Frequency-Mixing Laser

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Chinese Physics Letters 2001年第2期18卷 230-232页

作者： CHEN Xue-Yuan LUO Zun-Du HUANG yi-dong Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002

A theoretical model of the self sum-frequency-mixing(SFM)laser generated by a single crystal is proposed,in which spatial distribution of the pump and circulating fundamental lasers with arbitrary beam waists are taken into *** model is then applied to two kinds of crystals of current interest,Nd:YAI_(3)(BO_(3))_(4) and Nd:Ca_(4)GdO(BO_(3))_(3).Numerical analyses of the self-SFM laser properties predict and confirm some experimental *** model proposed is not limited to self-SFM lasers and may be applied to general analyses of the fundamental or nonlinear laser generation with Gaussian beams.

关键词： Nd: pump laser

The Chinese Stroke Association scientific statement:intravenous thrombolysis in acute ischaemic stroke

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Stroke & Vascular Neurology 2017年第3期2卷 147-159页

作者： Qiang dong yi dong Liping Liu Anding Xu Yusheng Zhang Huaguang Zheng Yongjun Wang 无 Department of Neurology Huashan Hospital affiliated to Fudan UniversityShanghai ShiChina Department of Neurology Beijing Tiantan Hospital affiliated to Capital Medical UniversityBeijingChina Department of Neurology and Stroke Center First Affiliated HospitalJinan UniversityGuangzhou ShiChina On behalf of the CSA Scientific Statement on Intravenous Thrombolysis in Acute Ischemic Stroke Writing Group

The most effective medical treatment for acute ischaemic stroke(AIS)is to offer intravenous thrombolysis during the ultra-early period of time after the *** based on the Consensus of Chinese Experts on Intravenous Thrombolysis for AIS in 2012 and 2014 Chinese Guidelines on the Diagnosis and Treatment of AIS,the rate of thrombolysis for AIS in China remained around 2.4%,and the rate of intravenous tissue plasminogen activator usage was only about 1.6%in real *** indication of thrombolysis for AIS has been expanded,and contraindications have been reduced with recently published *** order to facilitate the standardisation of treating AIS,improve the rate of thrombolysis and benefit patients who had a stroke,Chinese Stroke Association has organised and developed this scientific statement.

关键词： thrombolysis intravenous acute

Metal-organic frameworks bonded with metal N-heterocyclic carbenes for efficient catalysis

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National Science Review 2022年第6期9卷 64-73页

作者： Chang He Jun Liang Yu-Huang Zou Jun-dong yi Yuan-Biao Huang Rong Cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Science and Technology Innovation Laboratory for Optoelectronic Information of China

Metal N-heterocyclic carbenes(M-NHCs) on the pore walls of a porous metal-organic framework(MOF)can be used as active sites for efficient organic catalysis. Traditional approaches that need strong alkaline reagents or insoluble Ag2O are not, however, suitable for the incorporation of NHCs on the backbones of MOFs because such reagents could destroy their frameworks or result in low reactivity. Accordingly,development of facile strategies toward functional MOFs with covalently bound M-NHCs for catalysis is needed. Herein, we describe the development of a general and facile approach to preparing MOFs with covalently linked active M-NHC(M = Pd, Ir) single-site catalysts by using a soluble Ag salt AgOC(CF3)3as the source and subsequent transmetalation. The well-defined M-NHC-MOF(M = Pd, Ir) catalysts obtained in this way have shown excellent catalytic activity and stability in Suzuki reactions and hydrogen transfer reactions. This provides a general and facile strategy for anchoring functional M-NHC single-site catalysts onto functionalized MOFs for different reactions.

关键词： metal-organic framework N-heterocyclic carbene MIL-101 Suzuki reaction transfer hydrogenation

Evaluation of a rat meibomian gland dysfunction model induced by closure of meibomian gland orifices

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International Journal of Ophthalmology(English edition) 2018年第7期11卷 1077-1083页

作者： Zi-yi dong Ming ying Jie Zheng Lan-Jun Hu Jiang-Yan Xie yi Ma Department of Ophthalmology Tianjin Union Medical Center Tianjin Eye Hospital Tianjin Eye Institute Tianjin Key Lab of Ophthalmology and Visual Science

AIM： To find a stable, inexpensive, and reliable method to produce a rat meibomian gland dysfunction（MGD） model. METHODS： We inserted slim guidewires into the meibomian gland orifices of twelve Brown Norway rats and fulgurized every guidewire to destroy part of the meibomian gland. We then observed the morphological changes in the eyelid margin, and compared the data of tear breakup time（TBUT）, Schirmer I test, and the corneal fluorescence staining scores at different times（1, 2, 4, and 6 wk）. We observed pathological changes of the cornea, conjunctiva and meibomian gland, and we used real-time polymerase chain reaction to analyze epithelial growth factor（EGF）, interleukin-6（IL-6）, IL-8, tumor necrosis factor-α（TNF-α）, and Ki67. RESULTS： In the fourth week, compared with the control group, the TBUT of the model group began to decreased（P〈0.05）. The tear secretion remained stable（P〉0.05）. The corneal dots were significantly increased in the fourth week when the fusion stain began to appear（P〈0.05）. In the fourth week, partial meibomian gland openings had hoary secretions blocked, orifices were expanded, and there was a partial convex deformation. In the sixth week, the tissue section showed that the number of conjunctival goblet cells was decreased, epithelial cells were irregular, the epithelium was detached and rough, and meibomian glands were lost. The expressions of EGF, IL-6, IL-8, and TNF-α in corneal, conjunctival, and meibomian tissues were highly increased（P〈0.05）, but no statistical difference was found in the expression of Ki67 in corneal and conjunctival tissues（P〉0.05）. CONCLUSION： The MGD rat model, produced via electrocauterization of meibomian gland orifices, matched clinical manifestations and cytokine levels. Our research provides a new method of achieving an MGD animal model.

关键词： meibomian gland dysfunction animal model epithelial growth factor interleukin-6 interleukin-8 tumornecrosis factor-α Ki67

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： Lan-Kun Li Ming-yi dong Ze Gao Liang-Cheng-Long Jin Shu-Jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution

Influence of Feedback Level on Laser Polarization in Polarized Optical Feedback

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Chinese Physics Letters 2013年第8期30卷 62-65页

作者： WU Yun TAN yi-dong ZHANG Shu-Lian LI Yan The State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084

The influence of feedback level(or the amplitude of feedback light)on laser polarization in polarized optical feedback is investigated.A polarizer is placed in the feedback cavity to form the polarized feedback,and an attenuator is placed in the feedback cavity to tune the feedback *** laser intensity and polarization vary dramatically at different transmissivities of the *** to the experimental phenomenon,the range of the attenuator transmissivity is divided into three zones:the flipping zone,monostable zone,and bistable *** the monostable zone,the laser polarization is always perpendicular to the axis of the polarizer in the feedback *** may provide an effective way to choose or control laser polarization.A theoretical model based on the self-consistency of laser oscillation is presented to analyze the experimental results.

关键词： polarization laser polarized