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A New Disaccharide from the Fern Macrothelypteris digophlebia

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Chinese Chemical Letters 2000年第12期11卷 1063-1064页

作者： Ming Hua QIU jin Ming GAO Hu Qi LIU jian xi FU Kunming Institute of Botany The Chinese Academy of SciencesKunming 650204 Northwest Sci.&Tech.University of Agriculture and Forestry YanglingShaanxi 712100

A new disaccharide, digobiose 1, was isolated from the rhizomes of Macrothelypteris digophlebia (Bak.) Ching var. elegans (koidz.). Its structure which is very similar with that of sucrose was identified as alpha -D-g... 详细信息

关键词： Macrothelypteris digophlebia disaccharide digobiose

Synthesis and Properties of Polyetherketones Containing Sulfide and Phthalazinone

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Chinese Chemical Letters 2002年第7期13卷 607-608页

作者： Gong xiong LIAO xi Gao jian xiao Yuan GUO jin Yan WANG Department of Polymer Science Dalian University of TechnologyDalian 116012

High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1- phthalazinone (DHPZ)/4,4-thiobisphenol (TBP)/4,4-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT-IR and 1H-NMR. Thermal properties and solubility of copolymers were studied.

关键词： Polyetherketones 4,4-thiobisphenol 4-(4-hydroxyphenyl)-1-phthalazinone.

Interstellar Refractive Scintillation and Intraday Polarization Angle Swings

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Chinese Journal of Astronomy and Astrophysics 2005年第1期5卷 27-40页

作者： Shan-JieQian xi-zhenzhang A.Kraus NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 Max-Planck-InstitutfiirRadioastronomie aufdemHiigel6953121BonnGermany

Intraday polarization angle swings of ～180° observed in two sources (QSO0917+624 and QSO 1150+812) are discussed in the framework of refractive interstellar scintillationby a continuous interstellar medium. Model-fits to the I-, Q- and U- light curves were made for bothsources. It is shown that for the case of 0917+624 both the intraday intensity variations and thepolarization angle swing of ～180° could be explained consistently in terms of a four-componentmodel, which comprises one steady and two scintillating polarized components and one furthernon-polarized scintillating component. The polarization angle swing of ～180° observed in 1150+812,which occurred when the polarized flux density was almost constant, could not be explained in termsof refractive scintillation by a continuous medium and might be due to other mechanisms (e.g.,scintillation by interstellar clouds).

关键词： radio continuum galaxies polarization intraday variability scattering refractive scintillation quasars individual: QSO 0917+624 and 1150+812

A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： jian Li Yu-xi Ji xiao-xiao Ni Kai-He Lv xian-Bin Huang jin-Sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

Conductive microsphere monolayers enabling highly conductive pressure-sensitive adhesive tapes for electromagnetic interference shielding

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Advances in Manufacturing 2023年第2期11卷 212-221页

作者： xi Lu jin-Ming He Ya-Dong Xu jian-Hong Wei jian-Hui Li Hao-Hui Long You-Gen Hu Rong Sun Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongPeople's Republic of China Huawei Device(Dongguan)Company Ltd. Dongguan523000GuangdongPeople's Republic of China

Conductive adhesive tape is one kind of electromagnetic interference(EMI)shielding materials for electronic ***,the inferior conductivity of the pressure-sensitive adhesive(PSA)layer results in serious electromagnetic leakage at the conjunctions between the conductive tapes and target *** conductive fillers is a traditional method for highly conductive adhesive ***,the content of conductive fillers is needed to reach the percolation threshold,which is usually as high as tens of ***-content fillers result in significant loss of adhesive property and high fabrication ***,we introduce a rational architecture of conductive microsphere monolayer(CMM)in the PSA *** CMM connects the top and bottom surfaces of the PSA layer and improves its conductivity in the ***,low contents of conductive microspheres(≤5%(mass fraction,w))can achieve the target of conductivity improvement,but not result in the serious loss of the adhesive ***,the strategy of CMMs can balance the tradeoff between the conductivity and the adhesive property of conductive PSA ***,we demonstrate the superior EMI shielding performance of as-made conductive adhesive tapes,indicating their potential applications as the advanced EMI shielding materials in the electronic packaging.

关键词： Microsphere monolayer Pressure-sensitive adhesive(PSA) Conductive tapes Electronic packaging Electromagnetic interference(EMI)shielding

Energy-based dynamic parameter identification for Pasternak foundation model

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 631-643页

作者： Wang-xi Zhang Wei-Lei Lv jin-Yi Zhang xiong Wang Hyeon-Jong Hwang Wei-jian Yi College of Civil Engineering Hunan UniversityChangsha 410082China Hunan Provincial Key Lab on Diagnosis for Engineering Structures Hunan UniversityChangsha 410082China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Architecture Konkuk University120 Neungdong-roSeoul 05029Korea

Parameter identification of Pasternak foundation models(PFM)is never satisfactory,which discourages the application and popularization of *** the present study,an energy-based model to predict the dynamic foundation coefficients was proposed using the vibration kinetic energy and potential energy of a Pasternak foundation-rigid plate *** the basis of the Pasternak foundation,the relationship among the natural frequency,dynamic foundation coefficients,rigid plate configuration,and vibrating soil equivalent mass per unit area was *** obtain the natural frequencies of the Pasternak foundation-rigid plate system,dynamic tests were *** two or more dynamic test results of various rigid plates on a foundation,a set of equations of dynamic foundation coefficients was set up to directly identify the foundation coefficients and equivalent mass per unit area of vibrating *** feasibility of the proposed method was verified by comparing it with the outdoor and indoor test results and finite element analysis *** the proposed method is used to obtain the dynamic parameters,PFM can be generalized and applied more widely in engineering practice.

关键词： Pasternak foundation dynamic tests vibrating soil mass dynamic foundation coefficients dynamic characteristics

Construction of Aniline Trimer Based Conjugated Polymers through Schiff Base Reaction and Their Use as Feedstock for Infrared Stealth Coatings

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Chinese Journal of Polymer Science 2023年第6期41卷 851-858,I0005页

作者： xiang-Yu Li Li-Shuai Zong Yi-Bo Wang Qi Cao jin-Yan Wang xi-Gao jian State Key Laboratory of Fine Chemicals Liaoning High Performance Resin Engineering Research CenterDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China

In order to meet the demand for infrared stealth materials in the military field,conjugated polymers containing Schiff base moieties were designed and *** dialdehyde monomers were introduced and their effect on the comprehensive properties were systematically *** resulted polymers could be cast in solution to prepare polymer *** coatings exhibited high thermal stability up to 400℃ at 5%weight loss,and excellent mechanical performance with high Young’s modulus and *** infrared emissivity values varied from 0.587 to 0.627 at wavelength of 8-14μm and ranged from 0.595 to 0.609 at wavelength of 2-22μ***,it was found that the ATTPAL structure with carbazole moieties had a lower band gap and better electrical conductivity by photoelectric test and DFT theoretical ***,the infrared emissivity value of ATTPAL coating was the lowest compared with p-phenyl and pyridyl containing analogues,suggesting it was potential material for the future development of infrared stealth *** combined results showed that reducing the band gap and improving the electrical conductivity of the structure were both beneficial to the reduction of infrared *** would positively provide new ideas for the design of infrared stealth materials.

关键词： materials Schiff conductivity

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang jian Wang Panpan Zhang xiaomin Cheng Qinghua Guan jing Dong Bixian Chen Lujie Jia jing Zhang Yongzheng Zhang Yunjian Liu Hongzhen Lin School of Materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

Chinese Orthopedic Surgeons' Practice Regarding Postoperative Thromboembolic Prophylaxis after Major Orthopedic Surgery

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Chinese Medical Sciences Journal 2012年第3期27卷 141-146页

作者： Zhi-jian Sun Gui-xing Qiu xi-sheng Weng Yu Zhao jin jin Department of Orthopedics Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Objective To assess Chinese surgeon practice of thromboprophylaxis following major orthopedic surgery. Methods A questionnaire survey was conducted amongst Chinese orthopedic surgeons. A total of 293 surgeons were surveyed concerning five key aspects of thromboembolic prophylaxis after major orthopedic surgery at the proseminar of Chinese guidelines for prevention of venous thromboembolism (VTE) after major orthopedic surgery in January of 2009. Results Totally, 208 surgeons (71.0%) responded, successfully completing the questionnaire. Of them, 57.6% respondents selected combined basic, mechanical, and pharmacologic methods for thromboprophylaxis; 51.0% respondents prefer starting prophylaxis 12-24 hours after surgery; 60.3% surgeons would use chemoprophylaxis for 7-10 days; 47.6% respondents prefer VTE prevention based on patients' special conditions and needs upon discharge. "Safety" was the most repeated and emphasized factor during VTE prophylaxis. Conclusions Multimodal thromboprophylaxis is frequently used after major orthopedic surgery. Half surgeons prefer to start chemoprophylaxis 12-24 hours after surgery. Thromboprophylaxis regimen varies for discharged patients.

关键词： venous thromboembolism major orthopedic surgery survey thromboprophylaxis