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Preparation,Single-crystal Structure and Antibacterial Activity of N-((6-Bromine-2-methoxylquinoline-3-yl)benzyl)-3-morpho-line-N-(naphthalene-1-yl)propionamide 被引量:1
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作者 蔡志强 李姗蓉 孙铁民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期796-800,共5页
The halogenated hydrocarbon amination reaction between the original raw mate-rial N-((6-bromine-2-methoxylquinoline-3-yl)benzyl)-3-chlorine-N-(naphthalene-1-yl)propionamide and morpholine produces the target mol... The halogenated hydrocarbon amination reaction between the original raw mate-rial N-((6-bromine-2-methoxylquinoline-3-yl)benzyl)-3-chlorine-N-(naphthalene-1-yl)propionamide and morpholine produces the target molecule N-((6-bromine-2-methoxylquinoline-3-yl)benzyl)-3-morpholine-N-(naphthalene-1-yl)propionamide (C34H32BrN3O3,Mr=610.54),and its structure was characterized by 1H NMR,IR,H RMS and X-ray single-crystal diffraction.This crystal is of triclinic system,space group P1 with a=9.315(2),b=10.3449(12),c=15.901(3),α=80.981(14),β=76.996(17),γ=74.917(13)°,V=1433.6(5)3,Z=2,Dc=1.414 g/cm3,F(000)= 632,μ(MoKα)=1.47 mm-1,the final R=0.0735 and wR=0.2457.In total,5585 independent reflections including 3727 observed ones with I 〉 2σ(I) were collected.The dihedral angle between naphthyl and substituted quinolyl and that between phenyl and substituted quinolyl are 61.2(1) and 108.2(1)°,respectively.Through C-H…O and C-H…N hydrogen bonds among molecules,the whole molecule is stacked into a three-dimensional structure.In addition,π-π stacking among adjacent naphthalene rings makes the molecule more stable,and the morpholine ring adopts a chair conformation.The target molecule exhibits good antibacterial activity. 展开更多
关键词 synthesis crystal structure QUINOLINE antibacterial activity
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Syntheses and Single-crystal Structures of New Deficient Compounds in the R_6B_2C_2Q_(14)Family
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作者 刘彬文 曾卉一 +3 位作者 赵中燕 郑发鲲 郭国聪 黄锦顺 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1537-1543,共7页
Four new deficient compounds in the R6B2C2QI4 family, LasCaSn2.75S4 1, Y6A10.67Ge2S14 2, Er5.33Si4S14 3 and Er4Ge4SI4 4, have been obtained via a precursor/flux method. Single-crystal analysis indicated that their cry... Four new deficient compounds in the R6B2C2QI4 family, LasCaSn2.75S4 1, Y6A10.67Ge2S14 2, Er5.33Si4S14 3 and Er4Ge4SI4 4, have been obtained via a precursor/flux method. Single-crystal analysis indicated that their crystal structures consist of three types of building blocks: RS7 (R = La/Ca for 1, R = Y for 2, R = Er for 3 and 4) mono-triangonal prism, CS6 (C = A1 for 1, C = Sn(2) for 2, C = Si(2) for 3, C = Ge(2) for 4) octahedron, and BS4 (B = Si for 1, B = Sn(1) for 2, B = Si(1) for 3, B = Ge(1) for 4) tetrahedron, as any other compounds belong to the R6B2C2Q14 family. 展开更多
关键词 RARE-EARTH NONCENTROSYMMETRIC crystal structure SULFIDE
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Syntheses and Single-crystal Structures of Ln_3Sn_(0.25)GeS_7 (Ln=La,Sm)
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作者 赵中燕 刘彬文 +4 位作者 曾卉一 姜小明 张明建 郑发鲲 郭国聪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1135-1139,共5页
Two new quaternary sulfides,La3Sn0.25GeS71 and Sm3 Sn0.25GeS72,have been synthesized by a facile solid-state reaction,and their crystal structures were determined by singlecrystal X-ray diffraction analysis.The two co... Two new quaternary sulfides,La3Sn0.25GeS71 and Sm3 Sn0.25GeS72,have been synthesized by a facile solid-state reaction,and their crystal structures were determined by singlecrystal X-ray diffraction analysis.The two compounds crystallize in the P6 3 space group,and the crystal data are as follows-La3Sn0.25GeS7:a=10.3335(7),c=5.8455(7),Z=2;Sm3Sn0.25GeS7:a=9.999(3),c=5.787(2),Z=2.Single-crystal analysis indicated that the two compounds consist of three types of building blocks:LnS 8 anti-tetragonal prism,SnS 6 octahedron,and GeS 4 tetrahedron. 展开更多
关键词 RARE-EARTH NON-CENTROSYMMETRIC crystal structure SULFIDE
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Synthesis, Single-crystal Structure and Fluorescence Property of a New Boron Compound Based on 2-(2'-hydroxyphenyl)-1H-benzimidazole
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作者 尹国杰 楚希杰 +3 位作者 张涛 毛海舫 王朝阳 阳勇福 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1994-2002,1847,共10页
A new boron compound [C27H21BN4O3] based on 2-(2?-hydroxyphenyl)-1 Hbenzimidazole has been synthesized and characterized by single-crystal X-ray diffraction, and its crystal crystallizes in the monoclinic system, spac... A new boron compound [C27H21BN4O3] based on 2-(2?-hydroxyphenyl)-1 Hbenzimidazole has been synthesized and characterized by single-crystal X-ray diffraction, and its crystal crystallizes in the monoclinic system, space group P21/n with a = 9.6544(5), b = 14.1558(8), c = 16.4314(9) ?, β = 97.730°, Mr = 460.29, V = 2225.2(2) ?~3, Z = 4, Dc = 1.374 g/cm~3, μ = 0.74 mm-1, S = 1.051, F(000) = 960, the final R = 0.0643 and w R = 0.1569 for 2233 observed reflections(I > 2σ(I)). The title compound is a B(III) center mononuclear molecule in the asymmetric unit. The typical structural characteristic of the title compound is the methanol group adopting a μ2-bridging mode to link two different adjacent chelating modes though two types of hydrogen bonds to form a one-dimensional supramolecular structure. Additionally, aromatic π-π stacking interactions between adjacent benzimidazolyl groups lead to a three-dimensional network. Furthermore, the stability and fluorescence property revealed the potential applications in the organic photoelectric material. 展开更多
关键词 SYNTHESIS crystal structure STABILITY fluorescence property
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Syntheses and Single-crystal Structures of Er_3Ge_xGeS_7 (1/4≤x≤1/2)
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作者 曾卉一 郭胜平 +1 位作者 郑发鲲 郭国聪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第10期1205-1209,共5页
As part of our systematic research on the acentric rare earth chalcogenides, the ErAlGeS5/KBr, Er3AgGeS7/KBr and Er6Ge3S14/KBr systems were investigated and three compounds belonging to the R6B2C2Q14 (R = rare earth,... As part of our systematic research on the acentric rare earth chalcogenides, the ErAlGeS5/KBr, Er3AgGeS7/KBr and Er6Ge3S14/KBr systems were investigated and three compounds belonging to the R6B2C2Q14 (R = rare earth, B = 6-coordinated element, C = 4-coordinated element, Q = S and Se) family were identified. These compounds crystallize in the P63 space group, and the crystal data are as follows: Er3Ge1/4GeS7, a = 9.6480(14), c = 5.7920(12) A^°, Z = 2; Er3Ge0.382(8)GeS7, a = 9.6360(14), c = 5.8460(12) A^°, Z = 2; Er3Ge1/2GeS7, a = 9.6061(13), c = 5.8346(18)A^°, Z = 2. Single-crystal analysis indicated that the Er3GexGeS7 (x = 1/4, 0.382(8), 1/2) structures consist of three types of building blocks: ErS7, GeS4 and GeS6 units. Er3MxGeS7 are deficient compounds with the B sites occupied partly by Ge(Ⅳ) and/or Ge(Ⅱ). 展开更多
关键词 rare-earth ehaleogenides aeentrie crystal structure DEFICIENT
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Single-crystal Structure of ScAlMgO_4
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作者 周海涛 梁宇 +2 位作者 黄万霞 叶宁 邹宇琦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期947-950,共4页
Crystals of scandium magnesium aluminate, ScAlMgO4, were grown from the melt prepared from stoichiometric quantities of Sc2O3, Al2O3 and MgO. Single-crystal X-ray diffraction indicates that ScAlMgO4 crystallizes in th... Crystals of scandium magnesium aluminate, ScAlMgO4, were grown from the melt prepared from stoichiometric quantities of Sc2O3, Al2O3 and MgO. Single-crystal X-ray diffraction indicates that ScAlMgO4 crystallizes in the space group R3 m with a = b = 3.2506(9) A, c = 25.152(8)A, V= 230.16(11)A^3, Z= 3, F(000) = 234,μ = 2.424 cm^-1, the final R = 0.0381 and wR = 0.1061 for 1874 observed reflections with I 〉 2σ(I). In ScAlMgO4, all Sc atoms are coordinated octahedrally, whereas AI or Mg atoms are forming a tetrahedron, or in a triangular bipyramid if one distant O atom is included. The structure of ScAlMgO4 is characterized by { [AlMgO4]^3-}∞^2 layers parallel to the ab plane, and they are further connected into a 3-dimen-sional framework by Sc atoms via O(1) atoms between the layers. 展开更多
关键词 scandium magnesium aluminate Czochralski method crystal structure
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Synthesis, Single-crystal Structure, and Optical and Magnetic Properties of CaEr_2S_4
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作者 ZENG Hui-Yi Mattausch Hansjtirgen +3 位作者 ZHENG Fa-Kun DONG Zhen-Chao GUO Guo-Cong HUANG Jin-Shun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第8期973-979,共7页
Brown needle-like crystals of CaEr2S4 were isolated as the major product from a reaction of elements and binary sulfides by a two-step flux technique. CaEr2S4 crystallizes in the orthorhombic space group Pnma with a=1... Brown needle-like crystals of CaEr2S4 were isolated as the major product from a reaction of elements and binary sulfides by a two-step flux technique. CaEr2S4 crystallizes in the orthorhombic space group Pnma with a=12.845(4), b=3.862(4), c=13.001(2)(A), V=645.0(7)(A)3,Z=4, F(000)=880,μ(MoKα)=27.794 mm^-1, the final R=0.0528 and wR=0.0562 for 1070observed reflections with I 〉 3σ(I). The CaEr2S4 structure forms a three-dimensional framework that consists of interconnected tetra-octahedral Er4S18 fragments. Ca^2+cations, in a monocapped trigonal prism geometry, are stuffed in two parallel rows into the one-dimensional channels along the b direction. CaEr2S4 is an infrared-transparent semiconductor with a band gap of 1.81 eV. Magnetic susceptibility measurements over 6~300 K indicate a Curie-Weiss paramagnetic behavior for the phase, with an effective magnetic moment of 9.64(1) μB per Er^3+ ion. 展开更多
关键词 rare-earth chalcogenides FLUX crystal growth crystal structure optical and magnetic properties
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Synthesis and Single-crystal Structure of a Silver(Ⅰ) Carboxyarylphosphonate: [Ag(H_2BCP)(4,4'-bipy)]·2H_2O
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作者 雷然 张汉辉 +5 位作者 胡进 柴小川 张帅 李创新 陈义平 孙艳琼 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第4期655-659,共5页
The title compound, a novel Ag(Ⅰ) carboxyarylphosphonate [Ag(H2BCP)(4,4'- bipy)]·2H2O (H3BCP = p-H2O3PCH2C6H4COOH, 4,4'-bipy = 4,4'-bipyridine), was synthesized by a hydrothermal reaction and characte... The title compound, a novel Ag(Ⅰ) carboxyarylphosphonate [Ag(H2BCP)(4,4'- bipy)]·2H2O (H3BCP = p-H2O3PCH2C6H4COOH, 4,4'-bipy = 4,4'-bipyridine), was synthesized by a hydrothermal reaction and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. It belongs to monoclinic system, space group P21/c with a = 5.7038(11), b = 22.397(4), c = 5.602(4) , β = 106.26(3)°, V = 1913.4(7) 3, Z = 4, C18H20N2O7PAg, Mr = 515.20, Dc = 1.788 g/cm3, μ = 1.182 mm–1, F(000) = 1040, the final R = 0.0404 and wR = 0.1216 for 4178 observed reflections with I 2σ(Ⅰ). In the structure, the Ag(Ⅰ) cations are bridged by 4,4'-bipy to give rise to 1D chains running along the b axis. These chains are linked further by the interactions of O (from BCP ligands) and Ag atoms to yield 2D layers. Hydrogen bonding interactions and weak π-π stacking interactions between 4,4'-bipy rings assemble such adjacent layers to generate a 3D supramolecular architecture. 展开更多
关键词 metal carboxyarylphosphonate Ag(Ⅰ) complex crystal structure
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Synthesis and Single-crystal Structure of a One-dimensional Zinc(Ⅱ) Phosphonate: [Zn_3(PhPO_3)_2(PhPO_3H)_2(Phen)_2]_n
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作者 曹彦宁 张汉辉 +5 位作者 黄长沧 张凤利 陈义平 张帅 张春刚 胡进 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第1期37-40,共4页
A new Zn(II) phosphonate complex, [Zn3(PhPO3)2(PhPO3H)2(Phen)2]n (Phen = 1,10-phenanthroline), has been synthesized and structurally determined by X-ray single-crystal diffraction. The complex crystallizes i... A new Zn(II) phosphonate complex, [Zn3(PhPO3)2(PhPO3H)2(Phen)2]n (Phen = 1,10-phenanthroline), has been synthesized and structurally determined by X-ray single-crystal diffraction. The complex crystallizes in the monoclinic system, space group C2/c with a = 14.997(3), b = 18.108(4), c = 17.237(3) A, β = 96.61(3)°, V = 4649.9(16) A3, Z = 4, C48H38N4O12P4Zn3, Mr = 1182.87, Dc = 1.690 g/cm3^,μ = 1.743 mm^-1, F(000) = 2400, the final R = 0.0363 and wR = 0.0963. In the structure, the connectivity between two 5-coordinated Zn(II) atoms and four phosphonates as well as two Phen ligands form a Zn2(PhPO3H)2(PhPO3)2(Phen)2 unit, and such a neighboring unit is bridged by 4-coordinated Zn(II) to give rise to a 1D chain along the c axis. The π-π stacking interactions between Phen rings assemble adjacent chains packed together to form a 3D supermolecular architecture. 展开更多
关键词 metal phosphonate phenylphosphonic acid Zn(Ⅱ) complex inorganic-organic hybrid compounds crystal structure
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Synthesis,Single-crystal Structure,and Computational Studies of a Yavapaiite Structure Compound:Pb(Sb0.5Fe0.5)(PO4)2
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作者 张炜龙 陈达贵 +3 位作者 李小燕 郭振刚 林晨升 余运龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第1期75-82,共8页
The single crystals and powder of a Yavapaiite Structure phosphate,namely,PbSb0.5Fe0.5(PO4)2,were synthesized by solid state method and characterized by X-ray single-crystal diffraction and powder diffraction.The ti... The single crystals and powder of a Yavapaiite Structure phosphate,namely,PbSb0.5Fe0.5(PO4)2,were synthesized by solid state method and characterized by X-ray single-crystal diffraction and powder diffraction.The title compound crystallizes in the monoclinic system,space group C2/c(No.15) with a = 16.716(4),b = 5.186(7),c = 8.130(2)A,β = 114.93(6)°,Z = 4,R(I 〉 2s(I)) = 0.0430,R indices(all data) = 0.0460,and T = 293(2) K.The title compound belongs to the Yavapaiite Structure A^(Ⅱ)M^(Ⅳ)(PO4)2 compounds,and the Sb1 atom and Fe1 atoms occupy the same site(M) and their occupancy factors are refined to be 0.5 and 0.5 having a sum occupancy factor of 1.0.Its structure consists of [M(PO)4]n^2n- layers running parallel to the(b,c) plane built up of cornerconnected MO6 octahedra and PO4 tetrahedra.Additionally,the calculations of energy band structure,and density of states have been performed with the density functional theory method.The studies of computational calculation and UV experimental results show that the new compound is an indirect band-gap insulator. 展开更多
关键词 phosphates solid-state syntheses single crystal yavapaiite structure computational calculation
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Syntheses of Two Chiral Clusters [η~5-C_5H_4C(NR)CH_3]- RuNiM(CO)_5(μ_3-S) (R =NH-C_6H_3-2,4-(NO_2)_2,M=Mo,3;M=W,4) and the Single-crystal Structure of Cluster 3
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作者 边治国 陈玉岗 +1 位作者 殷元骐 李庆山 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第3期301-304,共4页
The new chiral clusters [h5-C5H4C(NR)CH3]RuNiM(CO)5(m3-S) (R = NH-C6H3-2,4- (NO2)2, M = Mo, 3; M = W, 4) were synthesized and the structure of cluster 3 was determined by single-crystal X-ray analysis. Crystal data: C... The new chiral clusters [h5-C5H4C(NR)CH3]RuNiM(CO)5(m3-S) (R = NH-C6H3-2,4- (NO2)2, M = Mo, 3; M = W, 4) were synthesized and the structure of cluster 3 was determined by single-crystal X-ray analysis. Crystal data: C23H16O9N4MoNiRuS, Mr = 780.18, orthorhombic, space group Pbca with the following crystallographic parameters: a = 13.207(4), b = 16.036(5), c = 25.513(8) , Z = 8, V = 5403(3) 3, Dc = 1.918 g/cm3, m = 1.834 mm-1 and F(000) = 3072. The final R = 0.0512 and wR = 0.1132 for 2525 reflections with I > 2.00s(I). 展开更多
关键词 合成 手性基团 [η5-C5H4C(NR)CH3]RuNiM(CO)5(μ3-S) NH-C6H3-2 4-(NO2) 晶体结构 MO W 单晶 结构表征 多金属配合物
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Insight into the capacity degradation and structural evolution of single-crystal Ni-rich cathodes
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作者 Xiaodong Zhang Jiao Lin +5 位作者 Ersha Fan Qingrong Huang Su Ma Renjie Chen Feng Wu Li Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期68-76,I0003,共10页
Single-crystal Ni-rich cathodes are a promising candidate for high-energy lithium-ion batteries due to their higher structural and cycling stability than polycrystalline materials.However,the phase evolution and capac... Single-crystal Ni-rich cathodes are a promising candidate for high-energy lithium-ion batteries due to their higher structural and cycling stability than polycrystalline materials.However,the phase evolution and capacity degradation of these single-crystal cathodes during continuous lithation/delithation cycling remains unclear.Understanding the mapping relationship between the macroscopic electrochemical properties and the material physicochemical properties is crucial.Here,we investigate the correlation between the physical-chemical characteristics,phase transition,and capacity decay using capacity differential curve feature identification and in-situ X-ray spectroscopic imaging.We systematically clarify the dominant mechanism of phase evolution in aging cycling.Appropriately high cut-off voltages can mitigate the slow kinetic and electrochemical properties of single-crystal cathodes.We also find that second-order differential capacity discharge characteristic curves can be used to identify the crystal structure disorder of Ni-rich cathodes.These findings constitute a step forward in elucidating the correlation between the electrochemical extrinsic properties and the physicochemical intrinsic properties and provide new perspectives for failure analysis of layered electrode materials. 展开更多
关键词 single-crystal cathodes Capacity decay Phase transition Differential capacity analysis
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:4
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method structure Rheological properties Antioxidant activity Bile acid binding capacity
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Seabed structures and foundations related to deep-sea resource development:A review based on design and research 被引量:1
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作者 Shengjie Rui Haojie Zhang +3 位作者 Hang Xu Xing Zha Mengtao Xu Kanmin Shen 《Deep Underground Science and Engineering》 2024年第2期131-148,共18页
The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and minerals.Various infrastructures such as floating structures,seabed structures,and foundations have been developed to... The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and minerals.Various infrastructures such as floating structures,seabed structures,and foundations have been developed to exploit these resources.The seabed structures and foundations can be mainly classified into three types:subsea production structures,offshore pipelines,and anchors.This study reviewed the development,installation,and operation of these infrastructures,including their structures,design,installation,marine environment loads,and applications.On this basis,the research gaps and further research directions were explored through this literature review.First,different floating structures were briefly analyzed and reviewed to introduce the design requirements of the seabed structures and foundations.Second,the subsea production structures,including subsea manifolds and their foundations,were reviewed and discussed.Third,the basic characteristics and design methods of deep‐sea pipelines,including subsea pipelines and risers,were analyzed and reviewed.Finally,the installation and bearing capacity of deep‐sea subsea anchors and seabed trench influence on the anchor were reviewed.Through the review,it was found that marine environment conditions are the key inputs for any offshore structure design.The fabrication,installation,and operation of infrastructures should carefully consider the marine loads and geological conditions.Different structures have their own mechanical problems.The fatigue and stability of pipelines mainly depend on the soil‐structure interaction.Anchor selection should consider soil types and possible trench formation.These focuses and research gaps can provide a helpful guide on further research,installation,and operation of deep‐sea structures and foundations. 展开更多
关键词 ANCHORS floating structures pipelines RISERS subsea foundations
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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Multi-Material Topology Optimization for Spatial-Varying Porous Structures 被引量:1
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作者 Chengwan Zhang Kai Long +4 位作者 Zhuo Chen Xiaoyu Yang Feiyu Lu Jinhua Zhang Zunyi Duan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期369-390,共22页
This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volu... This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures. 展开更多
关键词 Topology optimization porous structures local volume fraction augmented lagrangian multiple materials
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Estimation-free spatial-domain image reconstruction of structured illumination microscopy 被引量:1
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作者 Xiaoyan Li Shijie Tu +4 位作者 Yile Sun Yubing Han Xiang Hao Cuifang kuang Xu Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期45-58,共14页
Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditiona... Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditional Wiener-filtering-based reconstruction algorithm operates in the Fourier domain,it requires prior knowledge of the sinusoidal illumination patterns which makes the time-consuming procedure of parameter estimation to raw datasets necessary,besides,the parameter estimation is sensitive to noise or aberration-induced pattern distortion which leads to reconstruction artifacts.Here,we propose a spatial-domain image reconstruction method that does not require parameter estimation but calculates patterns from raw datasets,and a reconstructed image can be obtained just by calculating the spatial covariance of differential calculated patterns and differential filtered datasets(the notch filtering operation is performed to the raw datasets for attenuating and compensating the optical transfer function(OTF)).Experiments on reconstructing raw datasets including nonbiological,biological,and simulated samples demonstrate that our method has SR capability,high reconstruction speed,and high robustness to aberration and noise. 展开更多
关键词 structured illumination microscopy image reconstruction spatial domain digital micromirror device(DMD)
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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation 被引量:1
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作者 Jingjing Liang Meina Zhang +6 位作者 Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期421-433,共13页
Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were... Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were extracted from fermented and non-fermented L.edodes and purified via DEAE-52 and Sephadex G-100.The components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and NMR.The results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage patterns.Furthermore,their immunomodulatory activities were evaluated with immunosuppressive mice.NF-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields. 展开更多
关键词 Lentinus edodes polysaccharide Lactobacillus fermentum fermentation structural analysis Immunoregulatory activity Nuclear magnetic resonance
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Understanding the failure mechanism towards developing high-voltage single-crystal Ni-rich Co-free cathodes
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作者 Jixue Shen Bao Zhang +4 位作者 Changwang Hao Xiao Li Zhiming Xiao Xinyou He Xing Ou 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1045-1057,共13页
Benefited from its high process feasibility and controllable costs,binary-metal layered structured LiNi_(0.8)Mn_(0.2)O_(2)(NM)can effectively alleviate the cobalt supply crisis under the surge of global electric vehic... Benefited from its high process feasibility and controllable costs,binary-metal layered structured LiNi_(0.8)Mn_(0.2)O_(2)(NM)can effectively alleviate the cobalt supply crisis under the surge of global electric vehicles(EVs)sales,which is considered as the most promising nextgeneration cathode material for lithium-ion batteries(LIBs).However,the lack of deep understanding on the failure mechanism of NM has seriously hindered its application,especially under the harsh condition of high-voltage without sacrifices of reversible capacity.Herein,singlecrystal LiNi_(0.8)Mn_(0.2)O_(2) is selected and compared with traditional LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM),mainly focusing on the failure mechanism of Cofree cathode and illuminating the significant effect of Co element on the Li/Ni antisite defect and dynamic characteristic.Specifically,the presence of high Li/Ni antisite defect in NM cathode easily results in the extremely dramatic H2/H3 phase transition,which exacerbates the distortion of the lattice,mechanical strain changes and exhibits poor electrochemical performance,especially under the high cutoff voltage.Furthermore,the reaction kinetic of NM is impaired due to the absence of Co element,especially at the single-crystal architecture.Whereas,the negative influence of Li/Ni antisite defect is controllable at low current densities,owing to the attenuated polarization.Notably,Co-free NM can exhibit better safety performance than that of NCM cathode.These findings are beneficial for understanding the fundamental reaction mechanism of single-crystal Ni-rich Co-free cathode materials,providing new insights and great encouragements to design and develop the next generation of LIBs with low-cost and high-safety performances. 展开更多
关键词 Li/Ni antisite defect Dynamic characteristic HIGH-VOLTAGE single-crystal Ni-rich Co-free cathodes Lithium-ion batteries
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