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A three-dimensional co-continuous network structure polymer electrolyte with efficient ion transport channels enabling ultralong-life all solid-state lithium metal batteries
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作者 Meng Wang Hu Zhang +2 位作者 Yewen Li Ruiping Liu Huai Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期635-645,共11页
Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility wit... Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with electrodes.Herein,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport entities.The preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range disorder.Remarkably,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid electrolyte.When used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 mV.The resulting Li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,respectively.Even after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%capacity.Moreover,it displayes stable cycling for over 180 cycles at a high current density of 0.5C.The super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries. 展开更多
关键词 solid-state electrolyte Lithium-metal batteries Liquid crystalline polymer COPOLYMER 3D co-continuous structure Long cycle stability
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Ba_2SbGaS_5 : Solid-state Synthesis, Crystal and Electronic Structures, and Property Characterization 被引量:1
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作者 耿磊 张浩 程文旦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期538-544,共7页
Single crystal of Ba2SbGaSs has been synthesized by the high temperature solidstate reaction method. The compound crystallizes in the orthorhombic space group Pnma with a = 12.177(4), b = 8.880(3), c = 8.982(3) ... Single crystal of Ba2SbGaSs has been synthesized by the high temperature solidstate reaction method. The compound crystallizes in the orthorhombic space group Pnma with a = 12.177(4), b = 8.880(3), c = 8.982(3) A, V= 971.4(6) A3, Z = 4, De = 4.284 g/cm3,μ = 14.487 mm-1, F(000) - 1096, the final R = 0.0171 and wR = 0.0384 for all data. The structure comprises an infinite one-dimensional 1∞[SbGaS5]4- anionic chain constructed from the GaS4 tetrahedra and the SbS5 polyhedra via sharing edge alternately. The paralleled 1∞[SbGaS5]4anionic chains engage with each other and form the two-dimensional Sb-Ga-S layer perpendicular to a-axis with the isolated Ba2+ cations arranged between layers. The IR spectrum and the UV-Vis spectrum have been investigated. Also, the first-principles band structure and density of states calculations indicate that the compound belongs to indirect semiconductor with the band gap of 2.1 eV, which is supported by the UV-Vis diffuse reflectance results. 展开更多
关键词 crystal structure solid-state synthesis X-ray diffraction electronic structure calculation
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Solid-state Synthesis at Low-heating Temperature and Crystal Structure of a Dinuclear Molybdenum Complex with Oxalate Ligand[Bu_4N]_2[Mo_2O_2(OH)_2Cl_4(C_2O_4)] 被引量:2
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作者 汤卡罗 倪海洪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第4期300-303,共4页
The title compound was synthesized by the solid-state reaction of (NH_4)_6Mo_7O_(24)·4H_2O, Na_2C_2O_4, NH_2OH·HCl and Bu_4NBr at 90 ℃ for 10 h and crystallized from acetone-ether. The green crystal belongs... The title compound was synthesized by the solid-state reaction of (NH_4)_6Mo_7O_(24)·4H_2O, Na_2C_2O_4, NH_2OH·HCl and Bu_4NBr at 90 ℃ for 10 h and crystallized from acetone-ether. The green crystal belongs to the monoclinic space group P2_1/n with a=9. 908(2), b= 17, 873(2), c= 13/450(2) A , β= 90. 09(1 )°,V = 2381. 6 (7 ) A ̄3 , D_c = 1. 359 g/cm ̄3 , Z= 2. The structure was refined to R =0. 0427 for 2562 reflections. The anion of the title compound can be described as an oxalate ligand (C_2O4 ̄2 ) bridging two [MoCl_2O(OH)] units, which contain Mo(V)atoms. 展开更多
关键词 crystal structure dinuclear molybdenum complex oxalate ligand
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Solid-state Synthesis,Crystal and Band Structures,and Optical Properties of a Novel Ternary Sulfide Eu_2Ga_2S_5
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作者 龚安华 孙岳玲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第12期2115-2122,共8页
One new ternary europium gallium sulfide, Eu2Ga2S5, has been synthesized by a facile solid-state route with boron as the reducing reagent. It crystallizes in the orthorhombic space group Pbca, with a = 11.976(1), b ... One new ternary europium gallium sulfide, Eu2Ga2S5, has been synthesized by a facile solid-state route with boron as the reducing reagent. It crystallizes in the orthorhombic space group Pbca, with a = 11.976(1), b = 11.074(1), c = 17.446(1)A^°, V = 1650.6(3)A^°^3, and Z = 8. Its 3-D structure is built by the connection between EuS 7 monocapped trigonal prisms and GaS 4 tetrahedra, and the latter connect with each other to form layer-like slabs. Its optical energy gap is determined to be 2.17 eV, which is also verified by the electronic band structure calculation. 展开更多
关键词 rare-earth sulfide solid-state reaction crystal structure band gap
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Crystal structure,phase transitions,and thermodynamic properties of magnesium metavanadate(MgV_(2)O_(6)) 被引量:1
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作者 Guishang Pei Cheng Pan +2 位作者 Dapeng Zhong Junyi Xiang Xuewei Lv 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1449-1460,共12页
As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile... As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile solid-state reaction by multistep-firing stoichiometric mixtures of MgO and V2O5 powder under an air atmosphere.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)occurred at 841 K and the enthalpy change was 4.37±0.04 kJ/mol.The endothermic effect at 1014 K and the enthalpy change was 26.54±0.26 kJ/mol,which is related to the incongruent melting ofβ-MgV_(2)O_(6).In situ XRD was performed to investigate phase transition of the as-prepared MgV_(2)O_(6)at high temperatures.The cell parameters obtained by Rietveld refinement indicated that it crystallizes in a monoclinic system with the C2/m space group,and the lattice parameters of a=9.280 A°,b=3.501 A°,c=6.731 A°,β=111.76°.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)was further studied by thermal kinetics,indicating that this process is controlled first by a fibril-like mechanism and then by a spherulitic-type mechanism with an increasing heating rate.Additionally,the enthalpy change of MgV_(2)O_(6)at high temperatures was measured utilizing the drop calorimetry,heat capacity was calculated and given as:Cp=208.3+0.03583T-4809000T^(−2)(298-923 K)(J mol^(−1)K^(−1)),the high-temperature heat capacity can be used to calculate Gibbs free energy of MgV_(2)O_(6)at high temperatures. 展开更多
关键词 MgV_(2)O_(6) crystal structure Phase transitions Thermodynamic functions
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Structural analysis of silk using solid-state NMR
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作者 Tetsuo Asakura 《Magnetic Resonance Letters》 2024年第3期19-34,共16页
Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric press... Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric pressure.The dragline silk fiber,which is essentially a spider's lifeline,surpasses the strength of a steel wire of equivalent thickness.Regrettably,humans have yet to replicate this process to produce fibers with similar high strength and elasticity in an eco-friendly manner.Therefore,it is of utmost importance to thoroughly comprehend the extraordinary structure and fibrillation mechanism of silk,and leverage this understanding in the manufacturing of high-strength,high-elasticity fibers.This review will delve into the recent progress in comprehending the structure of silks derived from silkworms and spiders,emphasizing the distinctive attributes of solidstate NMR. 展开更多
关键词 SILK Bombyx mori SPIDER solid-state NMR structure
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Effect of Fe_(2)O_(3)on the Structure,Physical Properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass
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作者 张峰 XIONG Dehua +7 位作者 谢俊 张继红 HAN Jianjun CHEN Dequan WEN Zhongquan FAN Zhenhua CHEN Lina SUN Tengfei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期954-961,共8页
The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching method.The glass network structur... The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching method.The glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,X-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope measurements.The change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass structure.The glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content increase.There is almost no thermal expansion coefficient change from different Fe_(2)O_(3)content.The glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)ions.The calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional crystallization.All of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals. 展开更多
关键词 calcium aluminosilicate glass network structure physical properties crystalLIZATION
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Cryo-EM combined with image deconvolution to determine ZIF-8 crystal structure
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作者 吴抗 杨柏松 +3 位作者 薛文华 孙大鹏 葛炳辉 王玉梅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期44-49,共6页
Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmissi... Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmission electron microscopy(TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy(cryoEM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7A and enhancing its critical electron dose to around 20 e^(-)/A^(2). In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function(CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images. 展开更多
关键词 cryo-electron microscopy(cryo-EM) ZIF-8 image deconvolution crystal structure determination
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Synthesis,crystal structures,and antibacterial activities of two zinc(Ⅱ) complexes bearing 5⁃phenyl⁃1H⁃pyrazole group
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作者 LIU Chao WU Jiang JIN Zhaolei 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1986-1994,共9页
A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(... A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2. 展开更多
关键词 zinccomplex 5⁃phenyl⁃1H⁃pyrazole THIOCYANATE crystal structure BACTERIA
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Advances in Liquid Crystal Epoxy:Molecular Structures,Thermal Conductivity,and Promising Applications in Thermal Management
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作者 Wenying Zhou Yun Wang +6 位作者 Fanrong Kong Weiwei Peng Yandong Wang Mengxue Yuan Xiaopeng Han Xiangrong Liu Bo Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期315-343,共29页
Traditional heat conductive epoxy composites often fall short in meeting the escalating heat dissipation demands of large-power,high-frequency,and highvoltage insulating packaging applications,due to the challenge of ... Traditional heat conductive epoxy composites often fall short in meeting the escalating heat dissipation demands of large-power,high-frequency,and highvoltage insulating packaging applications,due to the challenge of achieving high thermal conductivity(k),desirable dielectric performance,and robust thermomechanical properties simultaneously.Liquid crystal epoxy(LCE)emerges as a unique epoxy,exhibiting inherently high k achieved through the self-assembly of mesogenic units into ordered structures.This characteristic enables liquid crystal epoxy to retain all the beneficial physical properties of pristine epoxy,while demonstrating a prominently enhanced k.As such,liquid crystal epoxy materials represent a promising solution for thermal management,with potential to tackle the critical issues and technical bottlenecks impeding the increasing miniaturization of microelectronic devices and electrical equipment.This article provides a comprehensive review on recent advances in liquid crystal epoxy,emphasizing the correlation between liquid crystal epoxy’s microscopic arrangement,organized mesoscopic domain,k,and relevant physical properties.The impacts of LC units and curing agents on the development of ordered structure are discussed,alongside the consequent effects on the k,dielectric,thermal,and other properties.External processing factors such as temperature and pressure and their influence on the formation and organization of structured domains are also evaluated.Finally,potential applications that could benefit from the emergence of liquid crystal epoxy are reviewed. 展开更多
关键词 intrinsically thermal conductive epoxy liquid crystal unit ordered structure phonon transport thermal conductivity
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Syntheses,crystal structures,and quantum chemistry calculation of two Ni(Ⅱ)coordination polymers
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作者 LI Xiumei HUANG Yanju +1 位作者 LIU Bo PAN Yaru 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期2031-2039,共9页
Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmeth... Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2. 展开更多
关键词 coordination polymer nickel(Ⅱ)complex crystal structure quantum⁃chemical calculation
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Synthesis,crystal structure and photo-physical properties of tris(4-methyl-2,5-diphenylpyridine)iridium for OLED
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作者 FENG Yangyang XU Mingming +4 位作者 WANG Hongyou ZHU Yunyao LUO Yuan LEI Huaidong CHEN Honglai 《贵金属》 CAS 北大核心 2024年第3期28-32,共5页
Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent ma... Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry. 展开更多
关键词 OLED iridium complex phosphorescent material crystal structure photo-physical properties Ir(bmppy)_(3)
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The Crystal Structure Study of CaSrFe0.75Co0.75Mn0.5O6−δ by Neutron Diffraction
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作者 Amara Martinson Mandy Guinn Ram Krishna Hona 《Journal of Materials Science and Chemical Engineering》 2024年第1期29-35,共7页
The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The... The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75</sub>Co0.75</sub>Mn0.5</sub>O6−δ</sub>, with potential implications for its applications in various technological and scientific domains. 展开更多
关键词 XRD Neutron Diffraction Perovskite Oxides crystal structure solid-state Reaction
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Analyses of Reaction Mechanisms among Different Sulfonation Reagents and m-Diphenylamine and Crystal Structures of the Formed Compounds
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作者 Dongdong Chen Chundong Mi +2 位作者 Menglan Yuan Aiquan Jia Qian-Feng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第4期84-97,共14页
In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfoni... In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfonic acid. Traditional methods need to consume a lot of fuming sulfuric acid or concentrated sulfuric acid, resulting in high industrial large-scale production cost, more waste, and posing a serious environmental pollution risk. In this thesis, three different sulfonation reagents were used for the sulfonation reaction of m-phenylenediamine, and the reaction mechanisms and crystal structures of the three pathways were investigated. The three routes are: 1) one-step synthesis of monosulfonated compound 1 from raw material and sulfur trioxide (SO<sub>3</sub>);2) rapid reaction of raw material and chlorosulfonic acid to synthesize bisulfonated compound 2;3) direct eutectic crystallization of raw material and ordinary sulfuric acid to obtain compound 3. The crystal structure of the compounds synthesized by three paths was analyzed by X-ray single crystal diffraction, and compound 1 was characterized by NMR, Fourier infrared spectra, UV-visible spectrum and Mass spectrometry. The one-step synthesis of SO<sub>3</sub> as a sulfonation reagent has the advantages of mild reaction conditions, simple operation and low cost. 展开更多
关键词 2 4-Diaminobenzenesulfonic Acid Sulfur Trioxide (SO3) Spectrometry crystal structure
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Solid-State NMR Spectroscopic Approaches to Investigate Dynamics, Secondary Structure and Topology of Membrane Proteins
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作者 Shadi Abu-Baker Gary A. Lorigan 《Open Journal of Biophysics》 2012年第4期109-116,共8页
Solid-state NMR spectroscopy is routinely used to determine the structural and dynamic properties of both membrane proteins and peptides in phospholipid bilayers [1-26]. From the perspective of the perpetuated lipids,... Solid-state NMR spectroscopy is routinely used to determine the structural and dynamic properties of both membrane proteins and peptides in phospholipid bilayers [1-26]. From the perspective of the perpetuated lipids, 2H solid-state NMR spectroscopy can be used to probe the effect of embedded proteins on the order and dynamics of the acyl chains of phospholipid bilayers [8-13]. Moreover, 31P solid-state NMR spectroscopy can be used to investigate the interaction of peptides, proteins and drugs with phospholipid head groups [11-14]. The secondary structure of 13C = O site-specific isotopically labeled peptides or proteins inserted into lipid bilayers can be probed utilizing 13C CPMAS solid-state NMR spectroscopy [15-18]. Also, solid-state NMR spectroscopic studies can be utilized to ascertain pertinent informa- tion on the backbone and side-chain dynamics of 2H- and 15N-labeled proteins, respectively, in phospholipid bilayers [19-26]. Finally, specific 15N-labeled amide sites on a protein embedded inside oriented bilayers can be used to probe the alignment of the helices with respect to the bilayer normal [2]. A brief summary of all these solid-state NMR ap- proaches are provided in this minireview. 展开更多
关键词 solid-state NMR structure and DYNAMICS Membrane PROTEINS
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Probing microstructure of solid-state synthesized LiCoO_(2)with MAS NMR spectroscopy
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作者 Suyu Gu Guozhong Lu +4 位作者 Nianrui Guo Juncheng Xu Yu Jiang Ming Shen Bingwen Hu 《Magnetic Resonance Letters》 2023年第4期298-305,共8页
LiCoO_(2)is an important category of active cathode materials in lithium-ion batteries due to its high compacted electrode density,good thermal stability,and stable voltage platform.Recent works on LiCoO_(2)have focus... LiCoO_(2)is an important category of active cathode materials in lithium-ion batteries due to its high compacted electrode density,good thermal stability,and stable voltage platform.Recent works on LiCoO_(2)have focused on the realization of higher charging voltages to fully utilize its high theoretical capacity.However,an unambiguous atomic-level local probe is essential for the understanding of structure-function correlation.Here we employ highresolution solid-state nuclear magnetic resonance(NMR)spectroscopy to study the local atomic environments in LiCoO_(2)synthesized with three common sintering methods.While one-dimensional 7Li NMR shows distinct linewidth and subtle dependence on lithium over-stoichiometry,both 7Li and 59Co relaxation times are highly dependent on the sintering method.We prove that the two-step sintering method favors the elimination of unreacted Co3O4,thereby enabling the best discharge capacity in all-solid-state lithium batteries assembled with LiCoO_(2)/LGPS/LiIn,which is in accordance with its narrowest 7Li linewidth and the longest 7Li/59Co T1. 展开更多
关键词 LiCoO_(2) solid-state NMR T1 relaxation Local structure
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Crystallization microstructure of Mg_(65)Cu_(25)Y_(10) bulk amorphous alloy 被引量:3
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作者 黄康 陈刚 +2 位作者 赵玉涛 王国路 邵阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期831-836,共6页
Mg65Cu25Y10 bulk amorphous alloy specimens prepared by conventional copper mould method were heated at 200 °C for different time and the phase contents as well as microstructure were studied.The XRD results show ... Mg65Cu25Y10 bulk amorphous alloy specimens prepared by conventional copper mould method were heated at 200 °C for different time and the phase contents as well as microstructure were studied.The XRD results show that the crystallization of Mg65Cu25Y10 bulk amorphous alloy specimen becomes complete as the treating time increases and Mg2Cu,Mg24Y5 and HCP-Mg crystalline phases are found.Snowflake-like morphology is found in different specimens through SEM observation.The EDS patterns show that the composition of the snowflake-like structure is close to that of the as-cast alloy.Laminated structures are observed from the TEM images of the snowflake-like structure.From the electron diffraction patterns,it is seen that the snowflake-like structure is the combination of Mg24Y5 and amorphous matrix.The FCC-Mg phase in the matrix transforms into HCP-Mg during the heat-treating process. 展开更多
关键词 Mg-based bulk amorphous alloy crystalLIZATION snowflake-like structure laminated structure
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Synthesis and Crystal Structure of t he Complex of Antimony Trichloride and Dioxane 被引量:1
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作者 臧祥生 陈娅如 +2 位作者 栾绍嵘 钟国清 郭应臣 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第6期901-904,共4页
New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH... New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH_(2))_(4)O_(2)}_(1.5)].The crystal structure of the comple x belongs to cubic system,space group I-43d,a=17.1417(5)?,Z=16.The trivalent antimony ion not only bonds directly to three chlorine anions,but also is co ordinated by three oxygen atoms of th e dioxane molecules.Two oxygen atoms in a dioxane molecule wi ll coordinate to different antimony ions,respectively. 展开更多
关键词 dioxane complex of antimony trichloride synthesis crystal structure
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Crystal Structure and Photocatalytic Characteristics of Nanoscate Sb-doped TiO_2 Thin Films 被引量:1
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作者 任达森 章壮健 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期549-554,共6页
Nanoscale Sb doped titanium dioxide thin films photocatalyst (Ti1-xSbO2) were obtained from dip-coating sol-gel method. The influence of dopant Sb density on the crystal structure and the phase transformation of the... Nanoscale Sb doped titanium dioxide thin films photocatalyst (Ti1-xSbO2) were obtained from dip-coating sol-gel method. The influence of dopant Sb density on the crystal structure and the phase transformation of the thin tilms were characterized by X-ray diffraction (XRD) and Raman spectra. The results of XRD showed that as prepared lilms were not only in anatase state but also in brookite. The crystalline size was estimated to be around 13.3-20 nm. Raman spectra indicated there coexisted other phases and a transformation from brookite to anatase in the samples doped with 0.2% Sb. After doping a proper amount of Sb, the cryst,allization rate and the content of the anatase Ti1-x, SbO2 in the thin films was clearly enhanced because Sb replaced part. of the Ti of TiO2 in the thin films. The anode current density (photocurrent density) and the first order reaction speed constant (k) of t.hin films doped with 0.2% Sb reached 42.49 μA/cm^2 and 0.171 h/cm^2 under 254 nm UV illumination, respectively, which is about 11 times and 2 times that of the non doped TiO2 anode prepared by the same method respectively. 展开更多
关键词 crystal structure XRD pattern Raman spectra ANATASE DOPANT Anode current density
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Synthesis, crystal structure and magnetic properties of novel copper compound Cu(phen)(m-CBA)_2
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作者 周建良 霍艳 +4 位作者 王敏敏 王圆圆 古映莹 易小艺 张寿春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2660-2664,共5页
A novel compound Cu(phen)(m-CBA)2 was synthesized with m-chlorobenzoic acid(m-CBA), 1,10-phenanthroline(phen) and Cu(OAc)2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallograp... A novel compound Cu(phen)(m-CBA)2 was synthesized with m-chlorobenzoic acid(m-CBA), 1,10-phenanthroline(phen) and Cu(OAc)2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallography. It crystallizes in the monoclinic crystal system with C2/c space group, a=2.9699(4) nm, b=1.15452(2) nm, c=1.5335(2) nm, β=111.118(2)°, V=4.905 1(1) nm3, Z=8, F(000)=2 328, R1=0.072 8, wR2=0.223 4 [I2σ(I)]. Structure analysis shows that the copper center coordinates with two nitrogen atoms from one 1,10-phenanthroline molecule, two oxygen atoms from two m-chlorobenzoic acid molecules, giving a distorted squared planar coordination geometry. This novel compound shows paramagnetic interactions between copper centers. 展开更多
关键词 copper (II) compound conventional synthesis crystal structure magnetic properties
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