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PROMOTION EFFECT OF MELAMINE ON FLAME RETARDANCY OF EPOXY RESINS CONTAINING CAGED BICYCLIC PHOSPHATE

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Chinese Journal of Polymer Science 2007年第6期25卷 581-588页

作者： Jing-ping Hu Dao Li yan qin Xing-yi wang Laboratory for Advanced Materials Research Institute of Industrial Catalysis East China University of Science ＆ Technology Shanghai 200237 China

Caged bicyclic phosphate （CBP） and its dimelamine salt （PDS） were synthesized and added to epoxy resins to obtain the flame retarded epoxy resin composites. The flammability of the composites was characterized by the limiting oxygen index （LOI） and cone calorimeter tests. The LOI values of flame retarded composites increase consistently with the increase of flame retardant amounts, and they are almost the same when the loading of CBP is the same as that of PDS, although the phosphorus content of PDS is much lower than that of CBP. The total heat release increases in the order of CBP30/ER 〈 PDS30/ER 〈 PDS15/ER 〈 CBPI5/ER, whereas that of specific extinction area is CBP15/ER 〉 CBP30/ER 〉 PDS30/ER ≌ PDS15/ER. PDS exhibits more effective inhibition of oxidation of combustible gases. In the tests of thermogravimetric analyses （TG） and Fourier transform infrared spectroscopy （FT-IR）, it is found that the degradation of the composites is influenced greatly by the addition of flame retardants. By scanning electron microscopy （SEM）, a thick and tight char-layer is observed for PDS30/ER, resulting from the interaction of nitrogen species with phosphorus species. Therefore, the combination of CBP with melamine in the flame retarded system can improve the flame retardancy greatly.

关键词： Flame retardancy Thermal degradation Melamine Caged bicyclic phosphate Epoxy resin.

Porous carbon/Fe composites from waste fabric for high-efficiency electromagnetic wave absorption

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Journal of Materials Science & Technology 2022年第31期126卷 266-274页

作者： Jin-Bo Cheng Hai-Bo Zhao Ai-Ning Zhang yan-qin wang Yu-Zhong wang Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) State Key Laboratory of Polymer Materials EngineeringNational Engineering Laboratory for Eco-Friendly Polymer Materials(Sichuan)College of ChemistrySichuan UniversityChengdu 610064China

Nowadays,a large amount of waste fabrics has brought huge environmental and resource problems,while the traditional recycling routes are downcycling with low efficiency and complex separation ***,we demonstrate a green and facile route to up-recycle waste fabrics(cotton-polyester blending or cotton fabrics)into a high-performance microwave *** this design,an assistant coating was deposited onto the fiber surface of the waste fabric through the assembly of tannic acid-Fe^(2+)(TA-Fe^(2+)),which effectively catalyzed the polymer fiber into highly graphitized porous carbon fiber at high ***,the Fe nanoparticles from the reduction of Fe^(2+)ions were evenly embedded on the surface of porous carbon ***,the resultant porous carbon/Fe composites with hierarchi-cal microstructures displayed excellent microwave absorption ***,the microwave ab-sorber from waste polyester-cotton blended fabric could reach a minimum reflection loss(RL)of-50.5 dB at a thin coating thickness of 1.7 mm,and the minimum RL from waste cotton fabric absorber reached-47.1 dB at a thickness of 2.5 *** work provides a new idea to convert waste fabrics into high value-added microwave absorbing materials in a simple and environmentally friendly way,which will help reuse resources and protect the environment.

关键词： Up recycling Microwave absorption Waste fabrics Thin thickness

Hierarchical Ti_(3)C_(2)T_(x)@ ZnO Hollow Spheres with Excellent Microwave Absorption Inspired by the Visual Phenomenon of Eyeless Urchins

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Nano-Micro Letters 2022年第5期14卷 62-76页

作者： yan‑qin wang Hai‑Bo Zhao Jin‑Bo Cheng Bo‑Wen Liu Qiang Fu Yu‑Zhong wang Collaborative Innovation Center for Eco‑Friendly and Fire‑Safety Polymeric Materials(MoE) State Key Laboratory of Polymer Materials EngineeringNational Engineering Laboratory for Eco‑Friendly Polymer Materials(Sichuan)College of ChemistrySichuan UniversityChengdu 610064People’s Republic of China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Ingenious microstructure design and rational composition selection are effective approaches to realize high-performance microwave absorbers,and the advancement of biomimetic manufacturing provides a new *** nature,urchins are the animals without eyes but can“see”,because their special structure composed of regular spines and spherical photosensitive bodies“amplifies”the light-receiving ***,inspired by the above phenomenon,the biomimetic urchin-like Ti_(3)C_(2)T_(x)@ZnO hollow microspheres are rationally designed and fabricated,in which ZnO nanoarrays(length:~2.3μm,diameter:~100 nm)as the urchin spines are evenly grafted onto the surface of the Ti_(3)C_(2)T_(x) hollow spheres(diameter:~4.2μm)as the urchin spherical photosensitive *** construction of gradient impedance and hierarchical heterostructures enhance the attenuation of incident electromagnetic *** the EMW loss behavior is further revealed by limited integral simulation calculations,which fully highlights the advantages of the urchin-like *** a result,the Ti_(3)C_(2)T_(x)@ZnO hollow spheres deliver a strong reflection loss of−57.4 dB and broad effective absorption bandwidth of 6.56 GHz,superior to similar *** work provides a new biomimetic strategy for the design and manufacturing of advanced microwave absorbers.

关键词： Bioinspired Hierarchical heterostructures Ti_(3)C_(2)T_(x)MXene ZnO nanoarrays Microwave absorption

Ce(H_2O)_7Al(OH)_6Mo_6O_(18)·4H_2O: A New One-dimensional Zigzag Chainlike Structure of Anderson Cluster Linked by Cerium Ions

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Chemical Research in Chinese Universities 2005年第6期21卷 637-640页

作者： JIN Hua QI yan-fei qin Chao wang Xin-long wang En-bo XU Lin Institute of Polyoxometalate Chemistry Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

A new cerium polyoxomolybdate { [Ce （ H2 O） 7 Al （ OH ） 6 Mo6 O18 ] · 4H20 } （ compound 1 ） was synthesized and characterized by X-ray diffraction analysis, elemental analysis, TG analysis and IR spectrometry. Compound 1 exhibits a zigzag chain-like structure, which is constructed from an Anderson type anion and rare earth metal, Ce（ Ⅲ ）. These 1-D chains are further extended into a 3-D network by the aid of muhipoint hydrogen-bonding interactions.

关键词： One-pot reaction Zigzag chain-like polymer Rare earth metal Polyoxometalate

A new forsythenside from Forsythia suspensa

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Chinese Chemical Letters 2008年第10期19卷 1234-1236页

作者： yan Zhi wang qin Ge Ma Xiao Ke Zheng Wei Sheng Feng Henan College of Traditional Chinese Medicine Zhengzhou 450008 China

A new forsythenside, 4-hydroxy-4-[8-[[1-[（4-hydroxyphenyl）acetyl]-β-D-glucopyranosyl-6-]oxy]ethy1]-2,5-cyclohexadien-1- one, named forsythenside F, was isolasted from the plant of Forsythia suspensa （Thunb.） Vahl. The structure of the new compound was established on the basis of various spectroscopic analysis, including ^1H NMR, ^13C NMR, 2D NMR techniques （HMBC and HSQC）, and HR-ESI-MS.

关键词： Forsythia suspensa Forsythcnside Forsythcnside F

Hierarchical model for strain generalized streaming potential induced by the canalicular fluid flow of an osteon

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Acta Mechanica Sinica 2015年第1期31卷 112-121页

作者： Xiao-Gang Wu Wei-Lun Yu Hai-Peng Cen yan-qin wang Yuan Guo Wei-Yi Chen College of Mechanics Shanxi Key Lab. of Material Strength & Structural Impact Taiyuan University of Technology Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology

A hierarchical model is developed to predict the streaming potential （SP） in the canaliculi of a loaded os teon. Canaliculi are assumed to run straight across the os teon annular cylinder wall, while disregarding the effect of lacuna. SP is generalized by the canalicular fluid flow. Ana lytical solutions are obtained for the canalicular fluid veloc ity, pressure, and SP. Results demonstrate that SP amplitude （SPA） is proportional to the pressure difference, strain am plitude, frequency, and strain rate amplitude. However, the key loading factor governing SP is the strain rate, which is a representative loading parameter under the specific phys iological state. Moreover, SPA is independent of canalicu lar length. This model links external loads to the canalicu lar fluid pressure, velocity, and SP, which can facilitate fur ther understanding of the mechanotransduction and electro mechanotransduction mechanisms of bones.

关键词： Canaliculi Streaming potential (SP) - Poroe-laticity Fluid flow

Excess pore pressure behavior and evolution in deep coalbed methane reservoirs

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International Journal of Mining Science and Technology 2024年第6期34卷 763-781页

作者： Changqing Liu Zhaobiao yang Yong qin Xia yan Yunhai wang Zhe wang Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221008China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center of Coalbed Methane Development&Utilization Beijing 100095China PetroChina Coalbed Methane Company Limited Beijing 102200China SINOPEC East China Oil and Gas Company Nanjing 210000China

Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these *** some production data analysis techniques have been adapted from conventional oil and gas wells,there remains a gap in the understanding of pore pressure generation and evolution,particularly in wells subjected to large-scale hydraulic *** address this gap,a novel technique called excess pore pressure analysis(EPPA)has been introduced to the coal seam gas industry for the first time to our knowledge,which employs dual-phase flow principles based on consolidation *** technique focuses on the generation and dissipation for excess pore-water pressure(EPWP)and excess pore-gas pressure(EPGP)in stimulated deep coal *** have been developed respectively and numerical solutions have been provided using the finite element method(FEM).Application of this model to a representative field example reveals that excess pore pressure arises from rapid loading,with overburden weight transferred under undrained condition due to intense hydraulic fracturing,which significantly redistributes the weight-bearing role from the solid coal structure to the injected fluid and liberated gas within artificial pores over a brief ***,field application indicates that the dissipation of EPWP and EPGP can be actually considered as the process of well production,where methane and water are extracted from deep coalbed methane wells,leading to consolidation for the artificial ***,history matching results demonstrate that the excess-pressure model established in this study provides a better explanation for the declining trends observed in both gas and water production curves,compared to conventional practices in coalbed methane reservoir engineering and petroleum *** research not only enhances the understanding of DCBM re

关键词： Deep coalbed methane Consolidation Excess pore-water pressure Excess pore-gas pressure Production data analysis

Histopathological Effects of the Protein Toxin from Xenorhabdus nematophila on the Midgut of Helicoverpa armigera

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Agricultural Sciences in China 2006年第9期5卷 685-690页

作者： NANGONG Zi-yan wang qin-ying SONG Ping yanG Jun MAO Wen-jie College of Plant Protection Hebei Agricultural University/Biocontrol Center of Plant Diseases and Plant Pests of Hebei Province Baoding071001 P.R.China

Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin II was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin II on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane （PM） began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.

关键词： Xenorhabdus nematophila toxin Helicoverpa armigera midgut histopathology peritrophic membrane

Measurement of GaN/Ge（001） Heterojunction Valence Band Offset by X-Ray Photoelectron Spectroscopy

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Chinese Physics Letters 2010年第6期27卷 183-186页

作者： GUO yan LIU Xiang-Lin SONG Hua-Ping yanG An-Li ZHENG Gao-Lin WEI Hong-Yuan yanG Shao-yan ZHU qin-Sheng wang Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083

X-ray photoelectron spectroscopy has been used to measure the valence band offset （VBO） at the GaN/Ge heterostructure interface. The VBO is directly determined to be 1.13 ±0.19 eV, according to the relationship between the conduction band offset AEc and the valence band offset △Ev：△Ec =EgGaN -EgGe - △Ev, and taking the room-temperature band-gaps as 3.4 and 0.67eV for GaN and Ge, respectively. The conduction band offset is deduced to be 1.6±0.19 eV, which indicates a type-I band alignment for GaN/Ge. Accurate determination of the valence and conduction band offsets is important for the use of GaN/Ge based devices.

关键词： Measurement Photoelectron Spectroscopy