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A dendritic Cu/Cu_(2)O structure with high curvature enables rapid and efficient reduction of carbon dioxide to C_(2) in an H-cell
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作者 Lei shao Bochen Hu +3 位作者 Jinhui Hao Junjie Jin Weidong Shi Min Chen 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期144-153,共10页
Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is chall... Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is challenging because of the inefficient mass transfer of the catalyst and the presence of the hydrogen evolution reaction(HER).In this study,dendritic Cu/Cu_(2)O with abundant Cu^(0)/Cu^(+)interfaces and numerous dendritic curves was synthesized in a CO_(2)atmosphere,resulting in the high selectivity and current density of the C_(2)products.Dendritic Cu/Cu_(2)O achieved a C_(2)Faradaic efficiency of 69.8%and a C_(2)partial current density of 129.5 mA cm^(-2)in an H-cell.Finite element simulations showed that a dendritic structure with a high curvature generates a strong electric field,leading to a localized CO_(2)concentration.Additionally,DRT analysis showed that a dendritic struc-ture with a high curvature actively adsorbed the surrounding high concentration of CO_(2),enhancing the mass transfer rate and achieving a high current density.During the experiment,the impact of the electronic structure on the performance of the catalyst was investigated by varying the atomic ratio of Cu^(0)/Cu^(+) on the catalyst surface,which resulted in improved ethylene selectivity.Under the optimal atomic ratio of Cu^(0)/Cu^(+),the charge transfer resistance was minimized,and the desorption rate of the intermediates was low,favoring C_(2) generation.Density functional theory calculations indicated that the Cu^(0)/Cu^(+) interfaces exhibited a lower Gibbs free energy for the rate-determining step,enhancing C_(2)H_(4) formation.The Cu/Cu_(2)O catalyst also exhibited a low Cu d-band center,which enhanced the adsorption stability of *CO on the surface and facilitated C_(2)formation.This observa-tion explained the higher yield of C_(2) products at the Cu^(0)/Cu^(+) interface than that of H_(2) under rapid mass transfer.The results of the net present value model showed that the H-cell holds promising industrial prospects,contingent upon it being a catalyst with both high selectivity and high current density.This approach of integrating the structure and composition provides new insights for ad-vancing the CO_(2)RR towards high-current C_(2) products. 展开更多
关键词 Reduction of Co_(2) High current Dendritic structure Cu/Cu_(2)o H-cell
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STUDY OF STRUCTURE AND RIGIDITY OF AIR-JET TEXTURED YARN(ATY)
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作者 王善元 吴静 张翼翔 《Journal of China Textile University(English Edition)》 EI CAS 1990年第2期19-25,共7页
This paper deals with the structure of air-jet textured yarn(ATY),especilly its core structurein dedail.It is described that overfeed of supply yarn does influence the ATY structure.Then thebending rigidity of ATY has... This paper deals with the structure of air-jet textured yarn(ATY),especilly its core structurein dedail.It is described that overfeed of supply yarn does influence the ATY structure.Then thebending rigidity of ATY has been measured and analyzed.The results shows that various supplyyarns affect the core structure and bending rigidity of ATY. 展开更多
关键词 air-jet TEXTURING yarn structure core structure overfeed bending RIGIDITY
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Structure and Properties of Pure Cotton Low-Twist Single Yarn Based on Addition of Long-Staple Cotton
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作者 WEN Run TAN Min +1 位作者 XU Nuo ZHANG Ruiyin 《Journal of Donghua University(English Edition)》 CAS 2022年第2期115-119,共5页
Pure cotton low-twist single yarn has good softness,bulkiness,and wearing comfort,but its lower strength makes the yarn break easily during the spinning process,which seriously affects the spinning effect and progress... Pure cotton low-twist single yarn has good softness,bulkiness,and wearing comfort,but its lower strength makes the yarn break easily during the spinning process,which seriously affects the spinning effect and progress.The addition of long-staple cotton helps to increase the average length and uniformity of the raw fiber,thereby improving the breaking load and spinnability of pure cotton low-twist single yarn.In this study,the addition of long-staple cotton,the twist factor,and the twist direction were used as variables to spin 22 kinds of combed 14.6 tex pure cotton low-twist single yarn with spinnability,and the breaking load,the hairiness,and the unevenness of the yarn were tested.The result shows that the spinnability of pure cotton low-twist single yarn is mainly related to the breaking load,and with the increase of the twist factor,the breaking load of low-twist single yarn shows an obvious upward trend.When the proportion of long-staple cotton is 70%,the breaking load of low-twist single yarn is the largest,and the harmful hairiness index and unevenness of the yarn are significantly improved. 展开更多
关键词 low twist single yarn long-staple cotton structure PRoPERTY
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Urchin-like Co3O4 Nanostructure and Their Electrochemical Behavior in Rechargeable Lithium Ion Battery 被引量:1
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作者 李惠 费广涛 +3 位作者 崔平 金翼 冯旭勇 陈春华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期343-347,I0004,共6页
3D urchin-like Co3O4 have been successfully prepared by calcination of the urchin-like precursors, which were synthesized through a facile hydrothermal route. The morphology and structure of the 3D urchin-like Co3O4 h... 3D urchin-like Co3O4 have been successfully prepared by calcination of the urchin-like precursors, which were synthesized through a facile hydrothermal route. The morphology and structure of the 3D urchin-like Co3O4 have been characterized by field emission scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy, and X-ray powder diffraction. The as-synthesized Co3O4 products are of urchin-like structures with approximated 5-7 μm in diameter, and are composed of numerous nanoparticles chains with the particles diameter of about 15 nm. This kind of urchin-like Co3O4 exhibits superior energy storage properties with the high capacity of 1.369 Ah/g and its good cyclic stability shows great potential in the rechargeable Li-ion battery. 展开更多
关键词 Co3o4 Urchin-like structure HYDRoTHERMAL Lithium ion battery Discharge capacity
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Microbial community structure in an integrated A/O reactor treating diluted livestock wastewater during start-up period 被引量:14
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作者 Lijiao Ren,Yining Wu,Nanqi Ren,Kun Zhang,Defeng Xing State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期656-662,共7页
In order to investigate the correlation between reactor performance and the microorganisms,an integrated A/O reactor was operated for 72 days to treat diluted livestock wastewater.Chemical oxygen demand (COD) remova... In order to investigate the correlation between reactor performance and the microorganisms,an integrated A/O reactor was operated for 72 days to treat diluted livestock wastewater.Chemical oxygen demand (COD) removal efficiency increased from 79% to 94%,with total nitrogen (TN) removal efficiency from 37% to 50% (HRT 7.4 hr) when the influent COD and TN were ca.1500 mg/L and 95 mg/L,respectively,and the outlet COD concentration was less than 100 mg/L at the end.Microbial community was monitored during start-up period by denaturing gradient gel electrophoresis (DGGE) based on 16S rRNA gene.DGGE profiles showed that microbial community had changed significantly during the start-up and these shifts were in accordance with the reactor performance.UPGMA clustering analysis showed that 14 anaerobic samples fell into five main groups and so did the aerobic ones,but the grouping patterns were different.Phylogenetic analysis indicated that microbial populations in the anaerobic compartment belonged to Firmicutes,Proteobacteria,Chloroflexi and Bacteroidetes,while Proteobacteria,Bacteroidetes,Firmicutes,Verrucomicrobiae and Nitrospira were present in the aerobic compartment.In the anaerobic compartment,more fermentative and acetogenic bacteria were detected during the start-up while denitrifying bacteria faded away.Two functional populations such as Nitrospira defluvii and Dechloromonas denitrificans were observed when nitrogen removal was high,indicating that simultaneous nitrification and denitrification occurred in the aerobic compartment. 展开更多
关键词 integrated A/o reactor community structure DYNAMICS denaturing gradient gel electrophoresis
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Synthesis and Crystal Structure of Bis[O,O'-di(2-phenylethyl)dithiophosphato](α,α'-bipyridine)copper(Ⅱ) 被引量:2
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作者 邹立科 谢斌 +2 位作者 赵彬 王军 冯建申 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1768-1773,共6页
A ternary adduct Cu[S2P(OCH2CH2Ph)2]2·bipy(bipy=α,α'-bipyridine) was syn-thesized and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The crystal belongs to the triclinic system... A ternary adduct Cu[S2P(OCH2CH2Ph)2]2·bipy(bipy=α,α'-bipyridine) was syn-thesized and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P1 with a=10.2320(2),b=11.5249(3),c=18.0916(3),α=98.95(1),β =103.601(1),γ=91.272(2)°,V=2044.49(7)3,Z=2,Dc=1.453 g/cm3,T=153(2) K,C42H44CuN2O4P2S4,Mr=894.51,λ(MoKα)=0.71073,μ=0.86 mm-1,S=0.999,(△/σ)max=0.002,the final R=0.0243 and wR=0.0704.A total of 9221 unique reflections were collected,of which 8573 with Ⅰ 〉2σ(Ⅰ) were observed.The Cu(Ⅱ) atom is five-coordinated in a rather distorted trigonal bipyramidal geometry(τ value=0.537).The Cu-S distances range from 2.3491(4) to 2.4829(4) ,and the Cu-N distances are 1.9987(12) and 2.0584(11) ,respectively.An interesting feature of this adduct resides in its two-dimensional(2D) open framework constructing through hydrogen bonding and π-π interactions. 展开更多
关键词 o o'-dialkyldithiophosphate copper(Ⅱ) adduct synthesis crystal structure
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Influences of Li Intercalation on the Electronic Structures of O2p and V3d Orbitals in α-V205
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作者 李志阳 林秀珠 吴启辉 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期241-245,339,共6页
The influence of Li intercalation on the electronic structures of oxygen and vanadium ions in α-V205 was investigated using first-principles calculations based on the density functional theory with local density appr... The influence of Li intercalation on the electronic structures of oxygen and vanadium ions in α-V205 was investigated using first-principles calculations based on the density functional theory with local density approximation. Two different intercalation sites for Li in the V205 lattices were considered. The calculation results demonstrate that intercalated Li ions at different sites show different effects on the electronic structures of O2p and V3d orbitals. But in both cases Li intercalation will weaken the V---O1 bonding and cause the split-off in V3d valence band to narrow or even disappear and simultaneously broaden the O2p conduction band. Further, the average electron transfer number from per intercalated Li2s to V3d orbitals is determined to total be about 0.52. 展开更多
关键词 V2o5 Li intercalation Electronic structure
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Synthesis of core-shell nanostructured Cr2O3/C@TiO2 for photocatalytic hydrogen production 被引量:6
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作者 Yang Chen Guobing Mao +4 位作者 Yawen Tang Heng Wu Gang Wang Li Zhang Qi Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期225-234,共10页
In this study,the Cr2O3/C@TiO2 composite was synthesized via the calcination of yolk–shell MIL-101@TiO2.The composite presented core–shell structure,where Cr-doped TiO2 and Cr2O3/C were the shell and core,respective... In this study,the Cr2O3/C@TiO2 composite was synthesized via the calcination of yolk–shell MIL-101@TiO2.The composite presented core–shell structure,where Cr-doped TiO2 and Cr2O3/C were the shell and core,respectively.The introduction of Cr^3+and Cr2O3/C,which were derived from the calcination of MIL-101,in the composite enhanced its visible light absorbing ability and lowered the recombination rate of the photogenerated electrons and holes.The large surface area of the Cr2O3/C@TiO2 composite provided numerous active sites for the photoreduction reaction.Consequently,the photocatalytic performance of the composite for the production of H2 was better than that of pure TiO2.Under the irradiation of a 300 W Xe arc lamp,the H2 production rate of the Cr2O3/C@TiO2 composite that was calcined at 500°C was 446μmol h−1 g−1,which was approximately four times higher than that of pristine TiO2 nanoparticles.Moreover,the composite exhibited the high H2 production rate of 25.5μmol h−1 g−1 under visible light irradiation(λ>420 nm).The high photocatalytic performance of Cr2O3/C@TiO2 could be attributed to its wide visible light photoresponse range and efficient separation of photogenerated electrons and holes.This paper offers some insights into the design of a novel efficient photocatalyst for water-splitting applications. 展开更多
关键词 Core-shell structure CR2o3 TIo2 Hydrogen generation PHoToCATALYST
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Synthesis of hierarchical dendritic micro–nano structure ZnFe_2O_4 and photocatalytic activities for water splitting 被引量:5
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作者 Zhongping Yao Yajun Zhang +2 位作者 Yaqiong He Qixing Xia Zhaohua Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第8期1112-1116,共5页
Hierarchical dendritic micro–nano structure Zn Fe_2O_4 have been prepared by electrochemical reduction and thermal oxidation method in this work. X-ray diffractometry, Raman spectra and field-emission scanning electr... Hierarchical dendritic micro–nano structure Zn Fe_2O_4 have been prepared by electrochemical reduction and thermal oxidation method in this work. X-ray diffractometry, Raman spectra and field-emission scanning electron microscopy were used to characterize the crystal structure, size and morphology. The results show that the sample(S-2) is composed of pure ZnFe_2O_4 when the molar ratio of Zn^(2+)/Fe^(2+)in the electrolyte is 0.35. Decreasing the molar ratio of Zn^(2+)/Fe^(2+), the sample(S-1) is composed of ZnFe_2O_4 and α-Fe_2O_3, whereas increasing the molar ratio of Zn^(2+)/Fe^(2+), the sample(S-3) is composed of ZnFe_2O_4 and Zn O. The lattice parameters of ZnFe_2O_4 are influenced by the molar ratio of Zn^(2+)/Fe: Zn at excess decreases the cell volume whereas Fe at excess increases the cell volume of Zn Fe_2O_4. All the samples have the dendritic structure, of which S-2 has micron-sized lush branches with nano-sized leaves. UV–Vis diffuse reflectance spectra were acquired by a spectrophotometer. The absorption edges gradually blue shift with the increase of the molar ratio of Zn^(2+)/Fe^(2+). Photocatalytic activities for water splitting were investigated under Xe light irradiation in an aqueous olution containing 0.1 mol·L^(-1)Na_2S/0.02 mol·L^(-1)Na_2SO_3 in a glass reactor. The relatively highest photocatalytic activity with 1.41 μmol·h-1· 0.02 g^(-1)was achieved by pure ZnFe_2O_4sample(S-2). The photocatalytic activity of the mixture phase of Zn Fe_2O_4 and α-Fe_2O_3(S-1) is better than ZnF e_2O_4 and ZnO(S-3). 展开更多
关键词 ZNFE2o4 ELECTRoCHEMICAL reduction and thermal oXIDATIoN DENDRITIC micro–nano structure Hydrogen production
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Electrochemical Cycled Structure of MnV_2O_6 Nanoribbons Synthesized via Hydrothermal Route 被引量:4
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作者 HU Fang ZHANG Chun-hua +4 位作者 ZHANG Song MING Xing CHEN Gang WEI Ving-jin WANG Chun-zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期528-530,共3页
1 Introduction Low-dimensional nanostructures, such as nanorods, nanowires, and nanotubes, have received much attention for their superior optical, electrical, catalytic and magnetic properties. Owing to their low di... 1 Introduction Low-dimensional nanostructures, such as nanorods, nanowires, and nanotubes, have received much attention for their superior optical, electrical, catalytic and magnetic properties. Owing to their low dimensionality and quantum continement effect, low-dimensional nanoscale materials can be exploited as fundamental building blocks for nanoscience and nanodevices^[1-3]. In recent years, efforts have been devoted to develop new approaches to synthesize one-dimensional(lD) nanostructrued vanadium oxides or vanadates materials, such as V205, NaV2Os, and CuV206, which have been widely investigated in catalytic or electrochemical fields due to their outstanding structural flexibility^[4-6]. 展开更多
关键词 MnV2o6 Hydrothermal route Electrochemical property Cycled structure
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Synthesis and Crystal Structure of a Novel Ternary Borate, NaSrB_5O_9 被引量:3
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作者 陈学安 左建龙 +2 位作者 常新安 臧和贵 肖卫强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第9期1081-1086,共6页
A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, spa... A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, space group P21/c with a = 6.499(2), b = 13.979(3), c = 8.045(2)A, β = 106.92(2)°, V = 699.2(3)A^3, Z = 4, Mr = 308.66, Dc = 2.932 g/cm^3, μ = 7.804 mm^-1, F(000) = 584, R = 0.0264 and wR = 0.0621 for 2426 observed reflections and 146 variables. NaSrB5O9 is a layered compound containing double ring B5O11 building units composed of two BO4 tetrahedra and three BO3 triangles. Each B5O11 unit is connected to four other equivalent units through exocyclic oxygen atoms to form a two-dimensional ∞^2 [B5O9]^3- layer. Symmetry-center related layers are stacked along the b axis and held together by Na^+ and Sr^2+ cations via electrostatic interactions. 展开更多
关键词 NaSrB5o9 BoRATE SYNTHESIS crystal structure
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2,2'-Bipyridine Adduct of Bis(O,O'-di(2-phenylethyl)dithiophosphato)cadmium(Ⅱ):Synthesis,Spectroscopic Characterization,Crystal Structure and Antibacterial Activity 被引量:1
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作者 谢斌 王艳美 +3 位作者 邹立科 王军 李玉龙 林肖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1457-1464,共8页
A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, ... A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, IR, UV-vis, 1H NMR, fluorescence spectroscopy, thermo-gravimetric analysis, and X-ray single-crystal diffraction. The crystal of 1 crystallizes in triclinic, space group P1 with a = 10.4607(19), b = 11.679(2), c = 18.480(3) A, a = 98.900(2), β = 103.321(2), ), = 91.779(2), V= 2165.2(7) A3, Dc = 1.447 g/cm3, Z = 2, C42H4404N2P2S4Cd, Mr = 943.37, F(000) = 968,μ = 0.814 mm-1, the final R = 0.0536 and wR = 0.1206 for 6275 observed reflections with 1 〉 2a(/) and R = 0.0690 and wR = 0.1339 for all data. The result shows that the Cd(1) centre is five-coordinated by two N and three S atoms in a highly distorted square pyramidal configuration. The C-H'"S hydrogen bonding interactions and a set of weak intermolecular r-r stacking between adjacent aromatic rings stabilize the structure and make 1 assemble into a 1D zig-zag chain. In addition, the antibacterial activities of 1 against Escherichia coli, Bacillus subtilis and Staphylococcus bacteria were also screened by disc diffusion method. 展开更多
关键词 o o'-dialkyldithiophosphate ADDUCT CADMIUM crystal structure antibacterial activity
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Rearrangement on surface structures by boride to enhanced cycle stability for LiNi0.80Co0.15Al0.05O2 cathode in lithium ion batteries 被引量:4
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作者 Shubiao Xia Wenjin Huang +5 位作者 Xiang Shen Jiaming Liu Feixiang Cheng Jian-Jun Liu Xiaofei Yang Hong Guo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第6期110-118,I0005,共10页
The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)mater... The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)materials in Li ion batteries(LIBs).Surface modification is an effective strategy for NCA cathodes,which could alleviate the degradation associated with surface processes.Herein,a surface structure rearrangement of NCA cathode secondary particles was reported by in-situ forming a solid electrolyte LiBO2.The LiBO2 is beneficial for alleviating the stress during charge/discharge process,thereby slowing down the rate of cracks formation in the secondary particles,which facilitates the Li+de-intercalation as well as prevents penetration of the liquid-electrolyte into the interior of the particles.As a result,the surface structure rearrangement NCA(RS-NCA)delivers a high discharge capacity of 202.5 m Ah g^-1 at 0.1 C,and exhibits excellent cycle stability with discharge capacity retaining 148 m Ah g^-1 after 200 cycles at 2 C.This surface structure rearrangement approach provides a new viewpoint in designing high-performance high-voltage LIBs. 展开更多
关键词 LiNi0.80Co0.15Al0.05o2 Surface structure REARRANGEMENT Particle PULVERIZATIoN Crack Cycle stability
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Studies on the Structure and Properties of Multiphase Al_2O_3 Abrasion-resistant Ceramics 被引量:3
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作者 WU Ren-Ping YU Yan RUAN Yu-Zhong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期805-810,共6页
The Al2O3 abrasion-resistant ceramics is successfully prepared by using waste aluminum sludge as the main raw material with the addition of a little clay, talc and barium carbonate. The crystal structure and microstru... The Al2O3 abrasion-resistant ceramics is successfully prepared by using waste aluminum sludge as the main raw material with the addition of a little clay, talc and barium carbonate. The crystal structure and microstructure of ceramic are characterized by means of XRD, SEM, etc., and the physical and mechanical properties are also tested. The results show that besides the phase of corundum, a little mullite, Mg-Al spinel and hyalophane phases also exist in the product. These phases are produced via reaction in-situ, which can inhibit the overgrowth of Al2O3 grain in grain boundary, and improve the integral property of the material. 展开更多
关键词 Al2o3 ceramic crystal structure property in-situ synthesis
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Synthesis and Crystal Structure of Bis[O,O'-bis(4-tert-butylphenyl)dithiophosphate]nickel(Ⅱ) 被引量:1
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作者 张秀兰 邹立科 +2 位作者 谢斌 赖川 李玉龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第5期779-785,共7页
A new O,O'-bis(4-tert-butylphenyl)dithiophosphate complex Ni[SSP(OC6H4But- p)2]2 (1) was synthesized and characterized by elemental analysis, IR, 1H NMR, thermogravimetric analysis (TGA) and single-crystal X-... A new O,O'-bis(4-tert-butylphenyl)dithiophosphate complex Ni[SSP(OC6H4But- p)2]2 (1) was synthesized and characterized by elemental analysis, IR, 1H NMR, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 12.8440(3), b = 6.18686(12), c=26.3018(5) , β=92.6135(18)°, V = 2087.87(7) 3, Z = 2, Dc = 1.345 g/cm3, μ = 0.780 mm-1, the final R = 0.0316 and wR = 0.0748 (Ⅰ 〉2σ(Ⅰ)). A total of 4269 unique reflections were collected, of which 3621 with Ⅰ 〉 2σ(Ⅰ) were observed. The NiII atom lies on an inversion center and is chelated by two (p-ButC6H4O)2PSS-ligands in a [NiS4] square-planar geometry with Ni-S bonds of 2.2408(5) and 2.2444(5) , respectively. A stepwise 1D chain structure is constructed via intermolecular S…S and C-H…S interactions. According to our knowledge this is the first case that intermolecular S…S interaction is observed in mononuclear transition metal complex of O,O'-dialkyldithiophosphates. 展开更多
关键词 o o'-dialkyldithiophosphate nickel(ll) complex synthesis crystal structure
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Influence of Fe_2O_3 Impurity on the Crystalline Structure of Cordierite Synthesized from Waste Aluminum Slag 被引量:3
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作者 WUWei-Qing RUANYu-Zhong YUYan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第4期483-487,共5页
The influence of Fe2O3 impurity on the crystalline structure of cordierite synthesized from waste aluminum slag is discussed. XRD and SEM techniques were employed to characterize the crystalline structure and micros... The influence of Fe2O3 impurity on the crystalline structure of cordierite synthesized from waste aluminum slag is discussed. XRD and SEM techniques were employed to characterize the crystalline structure and microstructure of each specimen. Philips X’pert plus software was used to determine the lattice parameters of each specimen. The results show that the Fe2O3 content of 0.8~1.6wt% is beneficial to the formation of cordierite, with the cordierite amount reaching 90wt%. So 0.8~1.6wt% is considered as the allowable Fe2O3 content in the specimens and 0.8wt% is determined to be the best after overall analysis. Plus software analysis shows that the cordierite in each specimen has the same symmetrical hexagonal structure as the single crystal, and the lattice parameters as well as the lattice dimensions change slightly. 展开更多
关键词 aluminum slag CoRDIERITE Fe2o3 impurity crystalline structure
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Synthesis, Crystal Structure and Hydrogenation Catalysis of a CF_3-BINAP(O)-Rh-COD Complex 被引量:1
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作者 杨红芬 卢伟 +2 位作者 刘蕾 刘宇 吴海臣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第11期1669-1675,共7页
The complex [(CF3-BINAP(O))Rh(COD)][ClO4]·Et2O (2, CFa-BINAP(O) = 2- {bis[3,5-bis(trifluoromethyl)phenyl]phosphino } -2 '- {bis [3,5-bis(trifluoromethyl)phenyl]phosphinyl } -1,1、-binaphthyl, COD = ... The complex [(CF3-BINAP(O))Rh(COD)][ClO4]·Et2O (2, CFa-BINAP(O) = 2- {bis[3,5-bis(trifluoromethyl)phenyl]phosphino } -2 '- {bis [3,5-bis(trifluoromethyl)phenyl]phosphinyl } -1,1、-binaphthyl, COD = 1,5-cyclooctadiene) was obtained directly from the reaction of CF3- BINAP(O) ligand with [Rh(COD)][C104]. Complex 2 has been characterized by single-crystal X-ray diffraction. The crystal adopts space group P21/n with a = 19.0727(4), b = 15.6275(4), c = 22.3039(6) A, fl = 112.3570(10)°, V= 6148.2(3) A3, Z = 4, Dc = 1.693 g/cm3, F(000) = 3144, μ(MoKa) = 0.500 mm-1, the final R = 0.0947 and wR = 0.2501. Structural studies reveal that Rh(I) is coordinated by one oxygen and one phosphorus in the same ligand. Asymmetric hydrogenation of acetami- docinnamic acid with compound 2 was also evaluated. 展开更多
关键词 BINAP(o ligand rhodium complex crystal structure asymmetric hydrogenation
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Electronic structures and optical properties of Si-and Sn-doped β-Ga_2O_3: A GGA+U study 被引量:2
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作者 Jun-Ning Dang Shu-wen Zheng +1 位作者 Lang Chen Tao Zheng 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期502-510,共9页
The electronic structures and optical properties of β-Ga_2O_3 and Si-and Sn-doped β-Ga_2O_3 are studied using the GGA + U method based on density functional theory. The calculated bandgap and Ga 3d-state peak of β-... The electronic structures and optical properties of β-Ga_2O_3 and Si-and Sn-doped β-Ga_2O_3 are studied using the GGA + U method based on density functional theory. The calculated bandgap and Ga 3d-state peak of β-Ga_2O_3 are in good agreement with experimental results. Si-and Sn-doped β-Ga_2O_3 tend to form under O-poor conditions, and the formation energy of Si-doped β-Ga_2O_3 is larger than that of Sn-doped β-Ga_2O_3 because of the large bond length variation between Ga–O and Si–O. Si-and Sn-doped β-Ga_2O_3 have wider optical gaps than β-Ga_2O_3, due to the Burstein–Moss effect and the bandgap renormalization effect. Si-doped β-Ga_2O_3 shows better electron conductivity and a higher optical absorption edge than Sn-doped β-Ga_2O_3, so Si is more suitable as a dopant of n-type β-Ga_2O_3, which can be applied in deep-UV photoelectric devices. 展开更多
关键词 density functional theory GGA + U method Si-doped β-Ga2o3 Sn-doped β-Ga2o3 electronic structure oPTICAL property
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Structure and electrochemical properties of La, F dual-doped LiLa_(0.01)Mn_(1.99)O_(3.99)F_(0.01) cathode materials 被引量:3
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作者 Meng Chen Shengjun Li Chuang Yang 《Journal of University of Science and Technology Beijing》 CSCD 2008年第4期468-473,共6页
The cathode materials LiMn2O4 and rare earth elements La-doped or La and F dual-doped spinel lithium manganese oxides.were synthesized by the citric acid-assisted sol-gel method. The synthesized samples were investiga... The cathode materials LiMn2O4 and rare earth elements La-doped or La and F dual-doped spinel lithium manganese oxides.were synthesized by the citric acid-assisted sol-gel method. The synthesized samples were investigated by differential thermal analysis (DTA) and thermogravimetry (TG) measurements, X-ray diffraction (XRD), scanning electronic microscope (SEM), cyclic voltammetry (CV), and charge-discharge test. XRD data shows that all the samples exhibit the same pure spinel phase, and the LiLa0.01Mn1.99O3.99F0.01 and LiLao.olMnl.9904 samples have smaller lattice parameters and unit cell volume than LiMn2O4. SEM indicates that LiLa0.01Mn1.99O3.99F0.01 has a slightly smaller particle size and a more regular morphology structure with narrow size distribution. The charge-discharge test reveals that the initial capacities of LiMn2O4, LiLa0.01Mn1.99O4, and LiLa0.01Mn1.99O3.99F0.01 are 129.9, 122.8, and 126.4 mAh·g^-1, and the capacity losses of the initial values after 50 cycles are 14.5%, 7.6%, and 8.0%, respectively The CVs show that the La and F dual-doped spinel displays a better reversibility than LiMn2O4. 展开更多
关键词 lithium ion battery cathode material LIMN2o4 structure electrochemical properties
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Controlling the Properties of Solvent-free Fe_3O_4 Nanofluids by Corona Structure 被引量:2
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作者 Yumo Tan Yaping Zheng +1 位作者 Nan Wang Aibo Zhang 《Nano-Micro Letters》 SCIE EI CAS 2012年第4期208-214,共7页
We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nano... We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nanofluids in order to show the effect of corona structure on the phase behavior, dispersion, as well as rheology properties. Results demonstrate novel liquid-like behaviors without solvent at room temperature. Fe3O4 magnetic nanoparticles content is bigger than 8% and its size is about 23 nm. For the solvent-free nanofluids,the long chain corona has the internal plasticization, which can decrease the loss modulus of system, while the short chain of corona results in the high viscosity of nanofluids. Long alkyl chains of modifiers lead to lower viscosity and better flowability of nanofluids. The rheology and viscosity of the nanofluids are correlated to the microscopic structure of the corona, which provide an in-depth insight into the preparing nanofluids with promising applications based on their tunable and controllable physical properties. 展开更多
关键词 Corona structure Fe3o4 nanoparticles Liquid-like behavior Solvent-free nanofluids
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