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Synthesis and crystal structure characterization of yttrium imido complex:The reactivity of 2-substituted-1-amino-o-carborane with yttrium dialkyl complex
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作者 GUO Liping 《无机化学学报》 北大核心 2025年第7期1409-1415,共7页
2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(... 2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a. 展开更多
关键词 yttrium imide O-CARBORANE synthesis structure characterization
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Recent progress and future directions in nanoglass materials: A deep insight into synthesis, characterization, and application
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作者 Anshuman Mishra Marisa A.Frechero +2 位作者 Arnaud Caron Pravin Kumar Singh Ashutosh Tiwari 《Nanotechnology and Precision Engineering》 2025年第1期132-162,共31页
This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of use... This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of uses.An overview of the current trends in nanoglass research connects them to the Sustainable Development Goals,highlighting the current relevance of this topic.The process of manufacturing nanoglasses is explained in depth,highlighting advanced approaches such as inert gas condensation and severe plastic deformation,among other techniques.The prime focus of this review is on analyzing the various dimensions of nanoglass materials,including their structural dynamics and electrical configurations,and how these features contribute to their exceptional thermal stability and mechanical strength.The magnetic characteristics of nanoglasses are examined,highlighting their potential for driving innovation across multiple industries.The primary emphasis is on the biological usefulness of nanoglasses,specifically examining their bioactivity and interaction with biological components,and emphasizing their growing use in nanoscale biomedical applications.With regard to the practical applications of nanoglasses,there are specific discussions of their contributions to biological evaluation,wound healing,catalysis,and environmental sustainability.There is an emphasis on the durability and resistance of nanoglasses in these contexts.The comprehensive overview of nanoglasses provided in this article highlights their significance as revolutionary materials in fields of science and technology.The potential of nanoglasses to contribute to a future that is more sustainable and health oriented is indicated.The article ends by discussing the future directions for nanoglass research and looks forward to the promising possibilities for further investigation and innovation. 展开更多
关键词 NANOGLASS synthesis characterization NANOCATALYSIS BIOMEDICINE
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Synthesis and characterization of high-purity SiO_(2) nanoparticles utilizing greater club rush:Exploring a promising natural source
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作者 Anuchit Sawangprom Tachgiss Jampreecha Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期1234-1244,共11页
High-purity SiO_(2)nanoparticles(SNPs)play a crucial role in various electronic applications,such as semiconductors,solar cells,optical fibers,lenses,and insulating layers,given their purity and particle size,which si... High-purity SiO_(2)nanoparticles(SNPs)play a crucial role in various electronic applications,such as semiconductors,solar cells,optical fibers,lenses,and insulating layers,given their purity and particle size,which significantly impact device efficiency.This study fo-cuses on the synthesis and characterization of pure SNPs through the chemical etching of greater club rush.White powder SNPs were pre-pared using HCl etching,and their thermal behaviors were analyzed via thermogravimetric analysis/differential scanning calorimetry.Structural properties were investigated using X-ray fluorescence,scanning electron microscopy,and transmission electron microscopy.X-ray absorption near-edge structure was employed to assess the oxidation state of the SNPs.The morphology of the SNPs after the first etching was amorphous,with sizes ranging from 50 to 100 nm,which increased to 50-200 nm after the second etching.Despite this size variation,the SNPs maintained a high purity level of 99.8wt%SiO_(2),comparable with industry standards.Notably,the second etching with 0.1-M HCl significantly enhanced the purity level,achieving 99.8wt%SiO_(2)mass.Furthermore,HCl etching facilitated the formation of SiO_(2)in the Si^(4+)oxidation state,akin to industrial SNPs.These findings underscore the critical role of HCl etching in synthesizing high-purity SNPs,with potential applications in advanced electronic devices. 展开更多
关键词 SILICA NANOPARTICLES synthesis characterization greater club rush
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Synthesis and Characterization of Poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)
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作者 ZHANG Mengyi CHENG Zhengzai +7 位作者 YANG Mian YU Qianwen TAN Zhiping WANDJI DJOUONKEP Lesly Dasilva CHENG Junpeng LIU Panpan DING Ling GAUTHIER Mario 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期582-588,共7页
High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)copolyesters(PBSIF-x)were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid(FDCA),with varying rati... High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)copolyesters(PBSIF-x)were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid(FDCA),with varying ratios of isosorbide(ISB)and 1,4-butylene glycol(BDO)catalyzed by antimony trioxide(Sb_(2)O_(3)).The PBSIF-x structures were investigated using FTIR and~1H NMR,while the GPC analysis exhibited the copolyesters molecular weights with number average molecular mass(M_n)in the range of 11079-15153 g/mol.The DSC results show that PBSIF-x copolyesters have a single glass-transition temperature(T_(g))(77.45-110.96℃),increasing with the increase in ISB content,while TGA analysis demonstrates excellent thermal stability up to 320℃.From the thermal result,properties of PBSIF-x copolyesters are found to be within the interval of their parent homologues poly(butylene 2,5-furandicarboxylate)(PBF)and poly(isosorbide 2,5-furandicarboxylate)(PIF),which confirms the aromatic/aliphatic blending within the polymer matrix for enhanced polymer stability and performance. 展开更多
关键词 COPOLYESTER 2 5-furandicarboxylic acid ISOSORBIDE melt polycondensation synthesis and characterization
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Synthesis and Characterization of Fe3O4 Nanoparticles by Sol-Gel Method Using Water as a Solvent
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作者 Ahmad Mustafa Usman Ali +4 位作者 Mukarama   Ali Iqbal Maria Qayyum Inam Ul Haq Fakhar Islam 《Advances in Nanoparticles》 2025年第1期1-11,共11页
Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticl... Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles. 展开更多
关键词 Fe3O4 Nanoparticles Sol-Gel synthesis Honeycomb Structures FTIR XRD SEM TGA VSM
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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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Recent advances of metal vacancies in energy and environmental catalysis:Synthesis,characterization,and roles
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作者 Long Sun Shunzheng Zhao +4 位作者 Sirui Gao Ronghui Zhu Yiran Tan Xiaolong Tang Honghong Yi 《Green Energy & Environment》 SCIE EI CAS 2025年第1期84-108,共25页
With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,off... With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,offers a promising avenue for researchers.However,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of scholars.Defect engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent years.Nonmetal vacancies have received extensive attention due to their simple form.Consequently,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this topic.Therefore,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic reactions.Additionally,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies. 展开更多
关键词 Metal vacancies CATALYSIS Construction strategies characterization techniques ROLES
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Hydrothermal synthesis, characterization and optical properties of La_2Sn_2O_7:Eu^(3+) micro-octahedra 被引量:6
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作者 杨锦瑜 苏玉长 刘雪颖 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期535-543,共9页
Pyrochlore structure La2Sn2O7:Eu3+ microcrystals with uniform octahedron shape were successfully synthesized via a hydrothermal route at 180 °C for 36 h. The crystal structure, particle size, morphologies, and ... Pyrochlore structure La2Sn2O7:Eu3+ microcrystals with uniform octahedron shape were successfully synthesized via a hydrothermal route at 180 °C for 36 h. The crystal structure, particle size, morphologies, and optical properties of the as-synthesized products were investigated by XRD, TEM, SEM, EDS, FT-IR, Raman spectroscopy and PL. The effects of pH of precursor solution, precursor concentration, reaction temperature, and time were investigated. The results reveal that pH of the precursor solution not only plays an important role in determining the phase of the as-synthesized products, but also has a significant influence on the morphologies of the samples. High-quality and uniform octahedrons with an average size of about 700 nm could be easily obtained at the pH value of 12. The possible formation mechanism of octahedral-like La2Sn2O7:Eu3+ microcrystals was briefly proposed. The photoluminescence spectra show that La2Sn2O7:Eu3+ micro-octahedra display stronger emission in the range of 582-592 nm compared with the samples with other shapes. 展开更多
关键词 pyrochlore structure hydrothermal synthesis growth mechanism optical properties
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Strategies and Advances in the Biomimetic Synthesis of Natural Products 被引量:1
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作者 Li-Jun Hu Zhi-Zhang Duan +2 位作者 Ying Wang Wen-Cai Ye Chun-Tao Che 《Engineering》 2025年第1期30-36,共7页
Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug... Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug discovery but also inspire innovative strategies in drug development.The biomimetic synthesis of natural products employs principles from biomimicry,applying inspiration from biogenetic processes to design synthetic strategies that mimic biosynthetic processes.Biomimetic synthesis is a highly efficient approach in synthetic chemistry,as it addresses critical challenges in the synthesis of structurally complex natural products with significant biological and medicinal importance.It has gained widespread attention from researchers in chemistry,biology,pharmacy,and related fields,underscoring its interdisciplinary impact.In this perspective,we present recent advances and challenges in the biomimetic synthesis of natural products,along with the significance and prospects of this field,highlighting the transformative potential of biomimetic synthesis strategies for both chemical and biosynthetic approaches to natural product synthesis in the pursuit of novel therapeutic agents. 展开更多
关键词 Natural products Natural product synthesis Biomimetic synthesis Biomimetic synthesis strategy
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Synthesis and characterization of arginine-modified and europium-doped hydroxyapatite nanoparticle and its cell viability 被引量:1
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作者 赵颜忠 朱军 +3 位作者 朱晒红 黄艳艳 李志友 周科朝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1773-1778,共6页
The arginine-modified and europium-doped hydroxyapatite nanoparticles(HAP-Eu) were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy(TEM),X-ray... The arginine-modified and europium-doped hydroxyapatite nanoparticles(HAP-Eu) were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy(TEM),X-ray diffractometry(XRD),Fourier transform infrared(FTIR) and zeta potential analyzer.The cell viability of HAP-Eu was tested by image flow cytometry.The results indicated that HAP-Eu is short column shapes and its size is approximately 100 nm,its zeta potential is about 30.10 mV at pH of 7.5,and shows no cytotoxicity in human epithelial cells and endothelial cells. 展开更多
关键词 HYDROXYAPATITE ARGININE EUROPIUM hydrothermal synthesis cell viability
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Synthesis and Characterization of Quaternary Complexes Ln(CH_2ClCOO)_2 (NO_3) (phen) 被引量:3
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作者 咸春颖 赵曙辉 +1 位作者 朱龙观 谢学鹏 《Journal of Donghua University(English Edition)》 EI CAS 2001年第3期88-90,共3页
Many binary lanthanide complexes have been studied. However, few mixed anion complexes with bidentate heterocyclic amines were synthesized. We synthesized mixed anion complexes Ln ( CH2 ClCOO )2 (NO3 ) ( phen) which w... Many binary lanthanide complexes have been studied. However, few mixed anion complexes with bidentate heterocyclic amines were synthesized. We synthesized mixed anion complexes Ln ( CH2 ClCOO )2 (NO3 ) ( phen) which was determined by elemental analyses . The IR spectra analyses indicate that NO3- , CH2 ClCOO- and phen are coordinated with Ln . The molar conductances of the complexes at 10-3 mol · L-1 were founded to be between 32.4 and 35.8 S·cm2· mol-1 , suggesting the nonelectrolytes in N-Dimethylformamide. And we determined the fluorescent spectra Eu(CH2ClCOO)2(NO3) ( phen ) and ESR spectra of Gd ( CH2 ClCOO )2 ( NO3) ( phen) . 展开更多
关键词 LANTHANIDE Quaternary Complex synthesis characterization.
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SYNTHESIS AND CHARACTERIZATION OF HYPERBRANCHED POLYURETHANE-BENZYLTETRAZOLE 被引量:2
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作者 施文芳 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第6期670-683,共14页
A series of hyperbranched polyurethane-benzyltetrazoles (H-PBTZs) with different linkage structures were synthesized via the polycondensation of hexamethylenediisocyanate as an A2 type monomer with (4-(1H-tetrazol... A series of hyperbranched polyurethane-benzyltetrazoles (H-PBTZs) with different linkage structures were synthesized via the polycondensation of hexamethylenediisocyanate as an A2 type monomer with (4-(1H-tetrazol-5- yl)benzyl)-diethanolamine (TBDEA) as a BB'2 type monomer in the absence of catalyst at different temperatures. The FTIR, and 13C and 1H-NMR spectroscopy were used to characterize the molecular structures of TBDEA and H-PBTZs as well as the counterpart linear polyurethane-benzyltetrazole (L-PBTZ). The molecular composition was determined by the reaction selectivity that the isocyanate group reacted with the hydroxyl group in diethanolamine segment or the active hydrogen atom on tetrazole ring. Raising reaction temperature was propitious to the reaction of isocyanate group with the active hydrogen atom on tetrazole ring. The degrees of branching (DB) for H-PBTZs obtained from the 1H-NMR spectra increased with raising reaction temperature. The wider molecular weight distribution of 1.7-2.9 for H-PBTZs was obtained via GPC analysis. TGA results showed that H-PBTZs had high thermal stability compared with L-PBTZ. 展开更多
关键词 synthesis Hyperbranched polyurethane-benzyltetrazole Degree of branching characterization.
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Synthesis and Characterization of Novel N-Ferrocenesulfonyl Benzimidazole 被引量:2
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作者 Bing Qin YANG, Peng Hui YANG, Ai Lin ZHU Department of Chemistry, Northwest University, Xian 710069 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期901-903,共3页
A new series of ferrocenesulfonyl benzimidazle has been synthesized and characterized by 1H NMR, FT-IR and elemental analysis. They are expected to have special bio-activity.
关键词 N-Ferrocenesulfonyl benzimidazole synthesis characterization.
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Synthesis,characterization and gas-sensing properties of Pd-doped SnO_2 nano particles 被引量:1
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作者 谭瑞琴 郭艳群 +3 位作者 赵俊华 李月 徐铁峰 宋伟杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1568-1573,共6页
SnO2 nano particles with various Pd-doping concentrations were prepared using a template-free hydrothermal method.The effects of Pd doping on the crystal structure,morphology,microstructure,thermal stability and surfa... SnO2 nano particles with various Pd-doping concentrations were prepared using a template-free hydrothermal method.The effects of Pd doping on the crystal structure,morphology,microstructure,thermal stability and surface chemistry of these nano particles were characterized by transmission electron microscope,X-ray diffractometer and X-ray photoelectron spectroscope respectively.It was observed that Pd-doping had little effect on the grain sizes of the obtained SnO2 nano particles during the hydrothermal route.During thermal annealing,Pd-doping could restrain the growth of grain sizes below 500℃ while the grain growth was promoted when the temperature increased to above 700℃.XPS results revealed that Pd existed in three chemical states in the as-synthesized sample as Pd^0,Pd^2+ and Pd^4+,respectively.Pd^4+ was the main state which was responsible for improving the gas-sensing property.The optimal Pd-doping concentration for better gas-sensing property and thermal stability was 2.0%-2.5% (mole fraction). 展开更多
关键词 SnO2 nano particles Pd-doping hydrothermal synthesis gas sensing property X-ray photoelectron spectroscopy
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The Synthesis and Characterization of High Molecular Weight Poly(phenylene sulfide/ether) 被引量:1
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作者 Ai Qun GU Mei Ju XIE Zi Li YU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第10期1373-1376,共4页
Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characteriz... Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR, ^1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed. PPSE had the same reflex indices as poly(p-phenylene sulfide), an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively. The product was soluble in common organic solvents such as NMP, N, N'-dimethylformamide, N, N'-dimethylacetamide and 1,2-dichloroethane. 展开更多
关键词 Poly(phenylene sulfide/ether) (PPSE) synthesis characterization.
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Synthesis and characterization of ε-VOPO_4 nanosheets for secondary lithium-ion battery cathode
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作者 陈泽华 马亿珠 +7 位作者 麻鹏程 曹建亮 王燕 孙广 王晓冬 哈日巴拉 张传祥 张战营 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期377-381,共5页
Vanadium (III) phosphate monoclinic VPO4·H2O was synthesized hydrothermally. The ε-VOPO4 nanosheets, formed by the oxidative de-intercalation of protons from monoclinic VPO4·H2O, can reversibly react wit... Vanadium (III) phosphate monoclinic VPO4·H2O was synthesized hydrothermally. The ε-VOPO4 nanosheets, formed by the oxidative de-intercalation of protons from monoclinic VPO4·H2O, can reversibly react with more than 1 mol lithium atoms in two steps. Crystal XRD analysis revealed that the structure of the ε-VOPO4 nanosheets is monoclinic with lattice parameters of α=7.2588(4) A, b=6.8633(2) A and c=7.2667(4) A. The results show that the ε-VOPO4 nanosheets have a thickness of 200 nm and uniform crystallinity. Electrochemical characterization of the ε-VOPO4 monoclinic nanosheets reveals that they have good electrochemical properties at high current density, and deliver high initial capacity of 230.3 mA· h/g at a current density of 0.09 mA/cm2. Following the first charge cycle, reversible electrochemical lithium extraction/insertion at current density of 0.6 mA/cm2 affords a capacity retention rate of 73.6% (2.0?4.3 V window) that is stable for at least 1000 cycles. 展开更多
关键词 lithium-ion battery NANOSHEET vanadium phosphate cathode material synthesis characterization
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Characterization and catalytic performance of CeO_2-Co/SiO_2 catalyst for Fischer-Tropsch synthesis using nitrogen-diluted synthesis gas over a laboratory scale fixed-bed reactor 被引量:2
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作者 Xiaoping Dai Changchun Yu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第1期17-23,共7页
The surface species of CO hydrogenation on CeO2-Co/SiO2 catalyst were investigated using the techniques of temperature programmed reaction and transient response method. The results indicated that the formation of H2O... The surface species of CO hydrogenation on CeO2-Co/SiO2 catalyst were investigated using the techniques of temperature programmed reaction and transient response method. The results indicated that the formation of H2O and CO2 was the competitive reaction for the surface oxygen species, CH4 was produced via the hydrogenation of carbon species step by step, and C2 products were formed by the polymerization of surface-active carbon species (-CH2-). Hydrogen assisted the dissociation of CO. The hydrogenation of surface carbon species was the rate-limiting step in the hydrogenation of CO over CeO2-Co/SiO2 catalyst. The investigation of total pressure, gas hourly space velocity (GHSV), and product distribution using nitrogen-rich synthesis gas as feedstock over a laboratory scale fixed-bed reactor indicated that total pressure and GHSV had a significant effect on the catalytic performance of CeO2-Co/SiO2 catalyst. The removal of heat and control of the reaction temperature were extremely critical steps, which required lower GHSV and appropriate CO conversion to avoid the deactivation of the catalyst. The feedstock of nitrogen-rich synthesis gas was favorable to increase the conversion of CO, but there was a shift of product distribution toward the light hydrocarbon. The nitrogen-rich synthesis gas was feasible for F-T synthesis for the utilization of remote natural gas. 展开更多
关键词 CeO2-Co/SiO2 catalyst Fischer-Tropsch synthesis surface species reaction condition nitrogen-rich synthesis gas product distribution
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Hydrothermal in situ Ligand Synthesis from 1,10-Phenanthroline-5,6-dione and Characterization of 1D Coordination Polymers [Co(bpdc)(H_2O)_3]·H_2O and [Cu(bpy)V_2O_6] 被引量:1
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作者 WANG Xiu-li BI Yan-feng LIN Hong-yan LIU Guo-cheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第3期250-253,共4页
Hydrothermal treatment of MCl2 ( M = Co or Cu ) , NH4 VO3, and 1,10-phenanthroline-5,6-dione (pdon) resulted in the formation of a duplex coordination polymer [ Co ( bpdc ) ( H2O ) 3 ] · H2O ( bpdc = 2,2... Hydrothermal treatment of MCl2 ( M = Co or Cu ) , NH4 VO3, and 1,10-phenanthroline-5,6-dione (pdon) resulted in the formation of a duplex coordination polymer [ Co ( bpdc ) ( H2O ) 3 ] · H2O ( bpdc = 2,2'-bipyridine-3,3'-dicarboxylate) and a chain-like coordination polymer [ Cu (bpy) V2O6 ] ( bpy = 2,2'-bipyridine ). X-ray single-crystal structural analysis shows that under hydrothermal conditions and in the presence of different transition metals, the organic reagent pdon was transformed in situ into bpdc and bpy, respectively. Mechanism of the in situ ligand synthesis reaction has been discussed. 展开更多
关键词 Hydrothermal synthesis In situ Ligand synthesis Coordination polymer Mechanism
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A comprehensive review on the scalable and sustainable synthesis of covalent organic frameworks
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作者 Yujie Wang Haoran Wang +3 位作者 Yanni Liu Manhua Peng Hongwei Fan Hong Meng 《Chinese Chemical Letters》 2025年第8期190-206,共17页
Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis... Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis of COFs is often time-consuming and conducted at a high temperature within a sealed vessel,and also requires a large amount of poisonous solvents,which is generally not available for scaling-up production and commercial application.In recent years,great efforts have been made to explore simple,green,and efficient approaches for COFs synthesis.In this comprehensive review,we summarized the advances in emergent strategies by highlighting their distinct features.Fundamental issues and future directions are also discussed with the object of bringing implications for large-scale and sustainable fabrication of COFs. 展开更多
关键词 Covalent organic frameworks Large-scaleproduction Green synthesis Efficient synthesis Ambient synthesis
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