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Comparative structural and electrochemical properties of mixed P2/O′3-layered sodium nickel manganese oxide prepared by sol-gel and electrospinning methods:Effect of Na-excess content 被引量:1
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作者 Thongsuk Sichumsaeng Atchara Chinnakorn +3 位作者 Ornuma Kalawa Jintara Padchasri Pinit Kidkhunthod Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第10期1887-1896,共10页
The effect of Na-excess content in the precursor on the structural and electrochemical performances of sodium nickel manganese oxide(NNMO)prepared by sol-gel and electrospinning methods is investigated in this paper.X... The effect of Na-excess content in the precursor on the structural and electrochemical performances of sodium nickel manganese oxide(NNMO)prepared by sol-gel and electrospinning methods is investigated in this paper.X-ray diffraction results of the prepared NNMO without adding Na-excess content indicate sodium loss,while the mixed phase of P2/O′3-type layered NNMO presented after adding Na-excess content.Compared with the sol-gel method,the secondary phase of NiO is more suppressed by using the electrospinning method,which is further confirmed by field emission scanning electron microscope images.N_(2) adsorption-desorption isotherms show no remarkably difference in specific surface areas between different preparation methods and Na-excess contents.The analysis of X-ray absorption near edge structure indicates that the oxidation states of Ni and Mn are+2 and+4,respectively.For the electrochemical properties,superior electrochemical performance is observed in the NNMO electrode with a low Na-excess content of 5wt%.The highest specific capacitance is 36.07 F·g^(-1)at0.1 A·g^(-1)in the NNMO electrode prepared by using the sol-gel method.By contrast,the NNMO electrode prepared using the electrospinning method with decreased Na-excess content shows excellent cycling stability of 100%after charge-discharge measurements for 300 cycles.Therefore,controlling the Na excess in the precursor together with the preparation method is important for improving the electrochemical performance of Na-based electrode materials in supercapacitors. 展开更多
关键词 sodium nickel manganese oxide mixed P2/O′3-type Na-excess content sol-gel method electrospinning method electrochemical properties
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Influence of Waveguide Properties on Wave Prototypes Likely to Accompany the Dynamics of Four-Wave Mixing in Optical Fibers
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作者 Jean Roger Bogning Marcelle Nina Zambo Abou’ou +4 位作者 Christian Regis Ngouo Tchinda Mathurin Fomekong Oriel Loh Ndichia Stallone Mezezem Songna François Béceau Pelap 《Journal of Applied Mathematics and Physics》 2024年第7期2601-2633,共33页
In this article, we study the impacts of nonlinearity and dispersion on signals likely to propagate in the context of the dynamics of four-wave mixing. Thus, we use an indirect resolution technique based on the use of... In this article, we study the impacts of nonlinearity and dispersion on signals likely to propagate in the context of the dynamics of four-wave mixing. Thus, we use an indirect resolution technique based on the use of the iB-function to first decouple the nonlinear partial differential equations that govern the propagation dynamics in this case, and subsequently solve them to propose some prototype solutions. These analytical solutions have been obtained;we check the impact of nonlinearity and dispersion. The interest of this work lies not only in the resolution of the partial differential equations that govern the dynamics of wave propagation in this case since these equations not at all easy to integrate analytically and their analytical solutions are very rare, in other words, we propose analytically the solutions of the nonlinear coupled partial differential equations which govern the dynamics of four-wave mixing in optical fibers. Beyond the physical interest of this work, there is also an appreciable mathematical interest. 展开更多
关键词 Optical Fiber Four Waves mixing Implicit Bogning Function Coupled Nonlinear Partial Differential Equations Nonlinear Coefficient Dispersive Coefficient Waveguide Properties
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Optical and electrical properties of BaSnO_(3) and In_2O_(3) mixed transparent conductive films deposited by filtered cathodic vacuum arc technique at room temperature
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作者 姚建可 钟文森 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期559-562,共4页
For the crystalline temperature of BaSnO_(3)(BTO)was above 650℃,the transparent conductive BTO-based films were always deposited above this temperature on epitaxy substrates by pulsed laser deposition or molecular be... For the crystalline temperature of BaSnO_(3)(BTO)was above 650℃,the transparent conductive BTO-based films were always deposited above this temperature on epitaxy substrates by pulsed laser deposition or molecular beam epitaxy till now which limited there application in low temperature device process.In the article,the microstructure,optical and electrical of BTO and In_(2)O_(3) mixed transparent conductive BaInSnO_(x)(BITO)film deposited by filtered cathodic vacuum arc technique(FCVA)on glass substrate at room temperature were firstly reported.The BITO film with thickness of 300 nm had mainly In_(2)O_(3) polycrystalline phase,and minor polycrystalline BTO phase with(001),(011),(111),(002),(222)crystal faces which were first deposited at room temperature on amorphous glass.The transmittance was 70%–80%in the visible light region with linear refractive index of 1.94 and extinction coefficient of 0.004 at 550-nm wavelength.The basic optical properties included the real and imaginary parts,high frequency dielectric constants,the absorption coefficient,the Urbach energy,the indirect and direct band gaps,the oscillator and dispersion energies,the static refractive index and dielectric constant,the average oscillator wavelength,oscillator length strength,the linear and the third-order nonlinear optical susceptibilities,and the nonlinear refractive index were all calculated.The film was the n-type conductor with sheet resistance of 704.7Ω/□,resistivity of 0.02Ω⋅cm,mobility of 18.9 cm2/V⋅s,and carrier electron concentration of 1.6×10^(19) cm^(−3) at room temperature.The results suggested that the BITO film deposited by FCVA had potential application in transparent conductive films-based low temperature device process. 展开更多
关键词 BaSnO_(3)and In_2O_(3)mixed film filtered cathodic vacuum arc deposition transparent conductive films microstructure optical properties electrical properties
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Impacts of solid physical properties on the performances of a slurry external airlift loop reactor integrating mixing and separation 被引量:2
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作者 Tian Zhang Qingshan Huang +3 位作者 Shujun Geng Aqiang Chen Yan Liu Haidong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期1-12,共12页
Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diam... Solid physical properties are vital for the design, optimization, and scale-up of gas–liquid–solid multiphase reactors. The complex and interactional effects of the solid physical properties, including particle diameter, density, wettability, and sphericity, on the hydrodynamic behaviors in a new external airlift loop reactor(EALR) integrating mixing and separation are decoupled in this work. Two semi-empirical equations are proposed and validated to predict the overall gas holdup and liquid circulating velocity satisfactorily, and then the individual influence of such solid physical properties is further investigated. The results demonstrate that both the overall gas holdup in the riser and the liquid circulating velocity in the downcomer increase with the contact angle, but decrease with particle size, density, and sphericity.Additionally, the impact of the particle size on the liquid circulating velocity is also profoundly revealed on a micro-level considering the particle size distribution. Moreover, the axial solid concentration distribution is discussed, and the uniformity of the slurry is described by the mixing index of the solid particles. The results show that a more homogeneous mixture can be achieved by adding finer particles other than attaining violent turbulence. Therefore, this work lays a foundation for the design, scale-up, and industrialization of the EALRs. 展开更多
关键词 Slurry reactor HYDRODYNAMICS Particle mixING Solid physical property
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Hydrothermal Synthesis, Crystal Structure and Magnetic Property of a Novel Mixed Valence Decatungstate: [Cu(2,2′-bipy)_2]_2Na_2W_6~VW4^(VI)O_(30)·2H_2O 被引量:1
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作者 李涛海 吕健 +1 位作者 高水英 曹荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期57-62,共6页
A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crys... A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crystal of 1 is of triclinic, space group P1^- with a= 10.9393(10), b = 12.0492(2), c = 12.3783(2)A, a = 80.631(10), β= 70.226(10), γ= 72.329(9)^o, V = 1459.64(4)A^3, Z = 1, Dc = 3.582 g/cm^3, F(000) = 1404, R = 0.0553 and wR = 0.1242 for 4607 observed reflections (I 〉 2σ(I)). The EPR spectrum of 1 indicates that its unpaired electrons are placed in the dx2-y2 orbital of the ground state of Cun. Furthermore, compound 1 shows an antiferromagnetic interaction. 展开更多
关键词 crystal structure DECATUNGSTATE mixed valence magnetic property
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Effect of Mixed Forests of Chinese Fir and Tsoong's Tree on Soil Properties 被引量:22
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作者 ZHENGYUSHAN DINGYINGXIANG 《Pedosphere》 SCIE CAS CSCD 1998年第2期161-168,共8页
Tsoong’stre(TsongiodendronodorumChun)isanancientandvestigespecieswhichisexclusivelydistributedinChina.Thetre... Tsoong’stre(TsongiodendronodorumChun)isanancientandvestigespecieswhichisexclusivelydistributedinChina.Thetreegrowsfastanditsw... 展开更多
关键词 杉木 混交林 土壤性质 观光森林
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Floristic Composition, Structure and Soil Properties of Mixed Deciduous Forest and Deciduous Dipterocarp Forest: Case Study in Madan Watershed, Myanmar 被引量:1
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作者 Kyaw Kyaw Myo San Thwin Nyunt Khaing 《American Journal of Plant Sciences》 2016年第2期279-287,共9页
Patterns of woody regeneration in terms of species composition and diversity were studied in mixed deciduous forest (MDF) and deciduous dipterocarp forest (DDF) in Minbyin reserved forest of Lewe Township. A total of ... Patterns of woody regeneration in terms of species composition and diversity were studied in mixed deciduous forest (MDF) and deciduous dipterocarp forest (DDF) in Minbyin reserved forest of Lewe Township. A total of 57 plant species of MDF belonging to 28 families and 342 individuals and 25 plant species of DDF consist of 15 families and 285 individuals were identified. Plant species diversity was quantitatively higher in the MDF (H' = 3.68) compared to the DDF (H' = 2.39). Tectona grandis showed the highest density (30), dominance (4.40 m<sup>2</sup>) and IVI (27.01) of MDF and Dipterocarpus tuberculatus also composed the highest density (109), dominance (9.02 m<sup>2</sup>) and IVI (81.87) in DDF. The smallest diameter class (10 - 20 cm) comprised with 29 species, 103 individuals in MDF and 18 species, 85 individuals in DDF. The size class distribution displayed a reverse J-shaped pattern. The largest numbers of species were concentrated in the smallest height class in both investigated forests because of height and diameter distribution is closely related. The total densities of seedlings and saplings were 1219 and 531 ha<sup>-1</sup> in MDF and 988 and 444 ha<sup>-1</sup> in DDF respectively. Although soil texture of (40 - 50 cm) and (90 - 100 cm) were sandy clay loam in mixed deciduous forest, the other layers of both investigated forests were sandy loam. 展开更多
关键词 Floristic Composition and Structure mixed Deciduous Forest Deciduous Dipterocarp Forest REGENERATION Soil Properties
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A Zinc(Ⅱ) Coordination Framework Based on Terpyridine and 5-Nitroisophthalic Acid Mixed Ligands: Synthesis, Crystal Structure and Fluorescence Property 被引量:7
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作者 陈勇强 田源 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第11期1587-1592,共6页
A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determin... A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated. 展开更多
关键词 coordination framework mixed-ligand approach crystal structure property
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Synthesis, Structure and Luminescent Property of a 2D Cd(Ⅱ) Coordination Polymer Based on Mixed-ligands of 1,3-Bis(imidazol)propane and Pyridine-3,5-dicarboxylic Acid 被引量:19
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作者 卢久富 刘举 +1 位作者 姜敏 葛红光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第2期248-252,共5页
A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compou... A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 1.40178(7), b = 1.72502(12), c = 1.41635(6) ran, β = 92.653(4)°, V = 3.4212(3) nm3, Z = 4, C16HIsCdNsO4, Mr = 453.73, Dc = 1.762 g/cm3, F(000) = 1808,μ = 1.310 mm1, R = 0.0899 and wR = 0.1945. In compound 1, each 3,5-pdc ligand links three Cd(lI) ions and each Cd(Ⅱ) attaches to bip ligands to form a complicated 2D double-layer structure. In addition, the thermal stability and luminescent property of 1 have been studied in the solid state at room temperature. 展开更多
关键词 Cd(Ⅱ) coordination polymer mixed-LIGANDS crystal structure luminescent property
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Electronic properties of 2D materials and their junctions
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作者 Taposhree Dutta Neha Yadav +8 位作者 Yongling Wu Gary J.Cheng Xiu Liang Seeram Ramakrishna Aoussaj Sbai Rajeev Gupta Aniruddha Mondal Zheng Hongyu Ashish Yadav 《Nano Materials Science》 EI CAS CSCD 2024年第1期1-23,共23页
With an extensive range of distinctive features at nano meter-scale thicknesses,two-dimensional(2D)materials drawn the attention of the scientific community.Despite tremendous advancements in exploratory research on 2... With an extensive range of distinctive features at nano meter-scale thicknesses,two-dimensional(2D)materials drawn the attention of the scientific community.Despite tremendous advancements in exploratory research on 2D materials,knowledge of 2D electrical transport and carrier dynamics still in its infancy.Thus,here we highlighted the electrical characteristics of 2D materials with electronic band structure,electronic transport,dielectric constant,carriers mobility.The atomic thinness of 2D materials makes substantially scaled field-effect transistors(FETs)with reduced short-channel effects conceivable,even though strong carrier mobility required for high performance,low-voltage device operations.We also discussed here about factors affecting 2D materials which easily enhanced the activity of those materials for various applications.Presently,Those 2D materials used in state-of-the-art electrical and optoelectronic devices because of the extensive nature of their electronic band structure.2D materials offer unprecedented freedom for the design of novel p-n junction device topologies in contrast to conventional bulk semiconductors.We also,describe the numerous 2D p-n junctions,such as homo junction and hetero junction including mixed dimensional junctions.Finally,we talked about the problems and potential for the future. 展开更多
关键词 2D materials Electrical properties p-n junctions mixed hereto junctions Homo junctions Electrical transport
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Synthesis, Structure, and Magnetic and Luminescent Properties of Rare Earth Coordination Polymers Constructed from Mixed Dicarboxylates
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作者 Nada Abdulhadi 张展睿 冯国强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第3期351-361,共11页
Three unique metal-organic framework coordination polymers, [Eu_2(bptc)(bdc)_2(H_2O)]_n(1), [Gd_2(bptc)(bdc)_2(H_2O)_4]_n(2) and [Dy_2(bptc)(bdc)_2(H_2O)_4]n(3)(1,2-H_2 BDC = 1,2-benzenedicarboylic acid, H_2 bptc = 4,... Three unique metal-organic framework coordination polymers, [Eu_2(bptc)(bdc)_2(H_2O)]_n(1), [Gd_2(bptc)(bdc)_2(H_2O)_4]_n(2) and [Dy_2(bptc)(bdc)_2(H_2O)_4]n(3)(1,2-H_2 BDC = 1,2-benzenedicarboylic acid, H_2 bptc = 4,4?-biphenyldicarboxylic acid) were synthesized by mixing two different multi-carboxylic acids with Ln2 O3(Ln = Eu, Gd and Dy) in hydrothermal condition. The three compounds are all three-dimensional and compounds 2 and 3 contain 4.289 × 6.507 ?~2 rectangularshaped one-dimensional open channels along the a direction. Additionally, the magnetic, luminescent and thermogravimetric properties were studied in detail. 展开更多
关键词 METAL-ORGANIC framework mixed CARBOXYLATES rare earth metals physical properties
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Studies on Colloidal Properties of Mixed Metal Hydroxide-Clay Aqueous Suspension
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作者 NOU wan-guo ZHANG Chun-guang +1 位作者 SUN De-jun HAN Shu-hua and WANG Guo-ting(Institute of Colloid and Interface Chemistry,Shandong University,Jinan,250100) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1995年第4期316-322,共7页
he electrical property,stability and rheological property of mixed metal hydroxide(MMH)-clay aqueous suspensions were studied via determining elec- trophoretic mobilities,heterocoagulation and rheological parameters.... he electrical property,stability and rheological property of mixed metal hydroxide(MMH)-clay aqueous suspensions were studied via determining elec- trophoretic mobilities,heterocoagulation and rheological parameters. The suspen- sions of MMH-Na-montmorillonite and MMH-Kaolinite may be transformed from negatively charged systems into positively charged systems through changing the ratio of MMH to clav. The increase of MMH content makes the stability of dilute MMH-clay suspensions decreased in negatively chrged systems and increased in positively chrged systems. The complete coagulations at near neutral systems oc- curs. In the concentrated MMH-clay suspension,the steric network structures may be formed between MMH and clay particles,which cause the apparent viscosity(AV)and Bingham yield point(YP) of the suspentqion to increase. There is a suit- able ratio of MMH to clay at which the AV and YP of the suspension attain a maximum value,which in agreement with “bridging theory”of polymer flocculation. 展开更多
关键词 mixed metal hydroxide CLAY Colloidal property SUSPENSION
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Syntheses,Structures and Properties of Lanthanide Coordination Polymers Constructed from Mixed Acid
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作者 孙长艳 吕琼 +3 位作者 张慧燕 李文军 常志东 郑向军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第1期27-32,共6页
Two new coordination polymers,[Ln(oba)(ox)0.5(H2O)2]n(Ln = Ho(1),Eu(2);H2oba = 4,4?-oxybis(benzoic acid),H2ox = oxalic acid) have been synthesized under hydrothermal conditions.According to single-cryst... Two new coordination polymers,[Ln(oba)(ox)0.5(H2O)2]n(Ln = Ho(1),Eu(2);H2oba = 4,4?-oxybis(benzoic acid),H2ox = oxalic acid) have been synthesized under hydrothermal conditions.According to single-crystal X-ray diffraction analyses,complex 1 crystallizes in the monoclinic system,space group P21/c with a = 13.783(2),b =10.0120(15),c = 12.1974(18) ,β = 105.217(2)°,V = 1624.2(4) 3,C15H12O9Ho,Mr = 501.18,Z = 4,Dc = 2.050 g/cm3,F(000) = 964,μ = 4.919 mm-1,λ(MoKα) = 0.71073 ?,GOOF = 1.124,the final R = 0.0239 and wR = 0.0570 for 3310 independent reflections with Rint = 0.0298.Complexes 2 and 1 are isostructural.Oba and ox ligands bridge the Ln(III) ions into 2D layers with(4,4) topology,which are further interlinked into a 3D supramolecular network by hydrogen bonds.TG curves of the two complexes are studied to examine their thermal stabilities.Additionally,complex 2 shows red fluorescence in the solid state at room temperature. 展开更多
关键词 mixed acid lanthanide ion fluorescent property crystal structure
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Structure and Luminescent Property of a Tetrahedral Silver(Ⅰ) Cluster Complex Based on Phosphor and Sulphur Mixed-ligand System 被引量:1
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作者 王跃 石永芳 +3 位作者 李晓波 邹晓川 何昱岑 王霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第7期1216-1222,共7页
A tetrahedral silver(I) cluster complex {Ag4[HC(PPh2)3](S2PPh2)3}ClO4(1,HC(PPh2)3 = 1,1,1-tris(triphenylphosphino)methane, S2PPh2 = diphenyldithiophosphinate) was synthesized by assembling silver ion with phosphor and... A tetrahedral silver(I) cluster complex {Ag4[HC(PPh2)3](S2PPh2)3}ClO4(1,HC(PPh2)3 = 1,1,1-tris(triphenylphosphino)methane, S2PPh2 = diphenyldithiophosphinate) was synthesized by assembling silver ion with phosphor and sulphur mixed-ligand system. The complex was characterized by single-crystal X-ray crystallography, high-resolution mass spectroscopy and thermal analysis. In the crystal structure, an inverted tetrahedron was constructed from Ag4 metal skeleton. The Ag4 cage was stabilized by three diphenyldithiophosphinate ligands and one 1,1,1-tris(triphenylphosphino)methane ligand. 1 exhibits luminescent properties in solid state. A bright yellow-green emission centered at 533 nm has been observed in solid state. Large Stokes' shifts with long range of emissive lifetime indicate that the emission likely originates from a triplet state parentage. 展开更多
关键词 SILVER cluster crystal STRUCTURE luminescent property mixed-LIGAND
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Effect of Recycled Mixed Powder on the Mechanical Properties and Microstructure of Concrete
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作者 Chao Liu Huawei Liu Jian Wu 《Journal of Renewable Materials》 SCIE EI 2022年第5期1397-1414,共18页
In this paper,recycled bricks and recycled concrete were applied to prepare eco-friendly recycled mixed powder(RMP)cementitious material,as a supplementary to replace conventional cement for improve the recycling of c... In this paper,recycled bricks and recycled concrete were applied to prepare eco-friendly recycled mixed powder(RMP)cementitious material,as a supplementary to replace conventional cement for improve the recycling of construction and demolition waste.Based on the effect of cementitious materials on the hydration of silicate cement,the effects of RMP on the workability,mechanical properties and microstructure of recycled mixed powder concrete(RMPC)with the different replacement ratios and the 8:4 and 6:4 mixing ratio of recycled brick powder(RBP)and recycled concrete powder(RCP)were investigated.The results showed that the fluidity of the mix decreased with increasing of the replacement ratio and the mixing ratio of RBP and RCP,but the influence of the fluidity was smaller within 15%replacement ratio.As the replacement ratio increases,the internal pore structure of RMPC tends to be loose and porous,which exhibits a significant pore volume distribution characteristic.The number of large capillaries was considerably increased at replacement ratio of 45%.The 7 d compressive strength of RMPC was slightly lower than that of ordinary concrete.The compressive and splitting tensile strengths of RMPC at 28 d increased by 4.2%and 10.1%,respectively,with increasing curing age at 15%replacement ratio and 6:4 mixing ratio.The RMPC mechanical strengths with RBP and RCP at the mixing ratio of 6:4 was higher than those of 8:2.Finally,a basis for the recycling of RBP and RCP in the construction industry can be provided by the results of this study. 展开更多
关键词 Recycled concrete recycled mixed powder pore structure mechanical properties
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SYNTHESIS, MAGNETIC PROPERTY AND X-RAY CRYSTAL STUCTURE OF MIXED VALENT COBALT COMPLEX SALT [Co~Ⅲ Cl_2(py)_4][Co~Ⅱ Cl_3(py)]
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作者 Hao XU Jin Yu LI +4 位作者 Zhong Zhi WU Jian Zhong ZOU Zheng XU Xiao Zeng YOU Zheng Chao DONG 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期59-60,共2页
Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690.... Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690.64, a=28.652(5), b=14.108(4), c=7.424(3) ;β=90.09(1); V=3001(2)~3; Z=4, Dc=1.53g/cm^3. Final R factor is 0.041. The structure consists of a discrete cation [Co~ⅢCl_2(py)_4]^+ and an anion [Co~Ⅱ Cl_3(py)]^-. The Co~Ⅲ ion is coordinated by two Cl^- and four pyridine nitrogen atoms to form an octahedral geometry, and Co~Ⅱ is coordinated by three Cl^- and one pyridine nitrogen atom to form the apices of a tetrahedron. The variable-temperature magnetic susceptility measurement shows no magnet-exchange interaction between Co~Ⅲ and Co~Ⅱ ions. 展开更多
关键词 CO Cl3 MAGNETIC property AND X-RAY CRYSTAL STUCTURE OF mixed VALENT COBALT COMPLEX SALT SYNTHESIS PY
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Soil Physical and Chemical Properties of Pure Pinus massoniana and Its Mixed Forests in Different Ages in Southern Guangxi 被引量:1
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作者 Zhongming HAO Shuirong WU +2 位作者 Lin QIN Ling TAN Wenfu GUO 《Asian Agricultural Research》 2018年第8期53-57,共5页
Six forest stands of 59,34 and 24 year-old Pinus massoniana forests and their mixed forests were selected at the Experimental Center of Tropical Forestry of Chinese Academy of Forestry,and 20 m × 20 m plot was se... Six forest stands of 59,34 and 24 year-old Pinus massoniana forests and their mixed forests were selected at the Experimental Center of Tropical Forestry of Chinese Academy of Forestry,and 20 m × 20 m plot was set up and soil samples were taken from 0-60 cm soil layers,to analyze the changes of soil nutrient content under different forest stands and forest ages. The results showed that soil moisture and the bulk density in the mesophytic forest land were higher than those of other forest lands. The highest soil porosity value was observed in the early forest land. Soil p H of different forest was 4. 45-4. 75,indicating the variation was small. Besides,it indicated that the mixed forest was more able to increase the soil fertility than the pure forest because that the variation of soil acidity,organic matter content and total P and K in 34 and24 year-old mixed forests were higher than those in pure forests of the same year old. However,the content of soil available P and K decreased with the increase of soil depth,and varied in terms of forest ages. From the changes of soil indicators in different forest lands,soil nutrients in the 34 year-old P. massoniana forest was superior to that of other forest stands. 展开更多
关键词 林业科学 中国 热带林业 理论研究
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Electron Donating Property and Catalytic Activity ofPerovskite-type Mixed Oxides (ABO_3) Consisting of Rare Earth and 3d Transition Metals
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作者 S.Sugunant and V.Meera(Dept. of Applied Chemistry, Cochin University of Science and Technology, Kochi-682022, India) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第3期229-231,共3页
The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have... The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have been correlated with the surface electron donor properties of these mixed oxides 展开更多
关键词 Activity type ABO3 Consisting of Rare Earth and 3d Transition Metals Electron Donating property and Catalytic Activity ofPerovskite-type mixed Oxides
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Magnetic Properties of One-Dimensional Ferromagnetic Mixed-Spin Model within Tyablikov Decoupling Approximation
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作者 陈渊 项颖 宋闯闯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期747-752,共6页
In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correla... In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correlationfunctions are obtained by using the Tyablikov decoupling approximation.Our results show that the magnetic susceptibilityand correlation length are a monotonically decreasing function of temperature regardless of the mixed spins.It isfound that in the case of S = s, our results of one-dimensional mixed-spin model is reduced to be those of the isotropicferromagnetic Heisenberg chain in the whole temperature region.Our results for the susceptibility are in agreement withthose obtained by other theoretical approaches. 展开更多
关键词 混合自旋模型 磁性能 铁磁 一维 逼近 解耦 格林函数方法 单调递减函数
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Critical Properties of Mixed Ising Spin System with Different Trimodal Transverse Fields in the Presence of Single-Ion Anisotropy
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作者 CHEN Qiang YAN Shi-Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1131-1136,共6页
在有效的地近似,效果 ofsingle 离子 anisotropy 和不同 trimodal 的框架以内,混合 spin-1/2 和 spin-1 Ising 系统的批评性质上的二个潜水艇格子的横向的地在简单立方的格子上被调查。更小的单个离子的 anisotropy 能放大阶段和一个... 在有效的地近似,效果 ofsingle 离子 anisotropy 和不同 trimodal 的框架以内,混合 spin-1/2 和 spin-1 Ising 系统的批评性质上的二个潜水艇格子的横向的地在简单立方的格子上被调查。更小的单个离子的 anisotropy 能放大阶段和一个更大的阶段能压抑磁性的订的磁性的订在低温度为 T- Ω _(1/2 ) 分阶段执行空间,当更小的 single-ionanisotropy 几乎不能改变价值时批评横向为 T- Ω _ 成立了 1 个空格。在另一方面,二不同 trimodal 影响 tricritical 点和磁性的订阶段上的集中在 T-D 空间在一些有趣的结果上拿的横向的 Selds。主要原因来自单个离子的 anisotropy,不同的横向的地和二 trimodaldistributions 的普通行动。 展开更多
关键词 临界性 混合自旋系统 三角形式横断场 单离子各向异性
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