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

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.

Influence of Waveguide Properties on Wave Prototypes Likely to Accompany the Dynamics of Four-Wave Mixing in Optical Fibers

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.

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

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.

Composition and properties of soil humus in a mixed forest of Cunninghamia lanceolata and Tsoongiodendron odorum

This study was conducted in Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian Province in January 1999. Taking pure stand of Chinese fir as control, the authors measured and studied the content of organic carbon, content of humic acid (HA), ratio of HA to fulvic acid (FA), and the characteristics of infrared light spectrum and visible light spectrum of soil humus in the mixed forest of Chinese fir and Tsoong?tree. Compared to humus composition in the pure stand of Chinese fir, the content of soil organic C, HA content, and the E4 value of HA for different layers of soil, except for the ratio of HA to FA, showed a significant increase in the mixed forest, while the ratios of E4 to E6 had a little decrease. The infrared light spectrum of humic acid had an absorptive peak at 1650 cm-1. It is concluded that the levels of humification and aromaticity of soil humus are higher in the mixed forest, which is favorable for the improvement of soil structure and nutrient supply, thus improving the soil fertility to a certain degree.

Mixed grain structure and mechanical property anisotropy of AZ40 magnesium alloy bar with diameter of 160 mm

The mixed grain structure and mechanical property anisotropy of AZ40 magnesium alloy bar with a diameter of 160 mm manufactured by ＂multi-direction forging（MDF） ＋ extrusion ＋ online cooling＂ technique were investigated by optical microscopy（OM）, scanning electron microscopy（SEM）, X-ray diffraction macro-texture measurement and room temperature（RT） tensile test. The results show that mixed grain structure is caused by the micro-segregation of Al in semi-continuous casting ingot. Homogenization of（380 °C, 8 h） ＋（410 °C, 12 h） cannot totally eliminate such micro-segregation. During MDF and extrusion, the dendrite interiors with 3%-4% Al（mass fraction） transform to fine grain zones, yet the dendrite edges with about 6% Al transform to coarse grain zones. XRD macro-textures of the outer, R/2 and center show typical fiber texture characteristics and the intensity of [0001]//Ra D orientation in the outer（11.245） is about twice as big as those in the R/2（6.026） and center（6.979）. The as-extruded AZ40 magnesium alloy bar has high elongation（A） and moderate ultimate tensile strength（Rm） in both extrusion direction（ED） and radius direction（Ra D）, i.e., A of 19%-25% and Rm of 256-264 MPa; however, yield strength（Rp0.2） shows anisotropy and heterogeneity, i.e., 103 MPa in Ra D, 137 MPa in ED-C（the center） and 161 MPa in ED-O（the outer）, which are mainly caused by the texture.（155 °C, 7 h） ＋（170 °C, 24 h） aging has no influence on strength and elongation of AZ40 magnesium bar.

Impacts of solid physical properties on the performances of a slurry external airlift loop reactor integrating mixing and separation

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.

Effects of Green Manure Mixed Cropping Patterns on Physical and Chemical Properties of Soil and Economic Characters of Flue-cured Tobacco

[Objective] The aim was to clear the suitable green manure cropping pat- terns in Xiangxi tobacco-planting areas. [Method] 8 treatments were set to study the effects of the monoculture and mixed cropping of common vetch （Vicia gigantea Bge.）, perennial ryegrass （Lofium） and rapeseed （Brassica campestris L.） on physi- cal and chemical properties of soil and economic characters of flue-cured tobacco. [Result] （1） Green manure turnover can reduce soil bulk density by 1.08%-8.62%, and the effect of green manure mixed cropping pattern was the best. （2） Green manure turnover also can increase the soil nutrient, soil organic matter, total nitro- gen （N）, total phosphorus （P）, total potassium （K）, alkali-hydrolyzale N, rapidly available P and rapidly available K by 1.44%-6.10%, 0.01-0.12 g/kg, 1.89%- 11.32%, 0.12%-3.56%, 1.06%-11.76%, 0.04%-18.93% and 0.98%-23.12%, respec- tively, and the effect of the monoculture of common vetch was the best.（3） The overall change of soil pH was not obvious.（4）Green manure turnover can increase the yield and output of flue-cured tobacco, and the effect of the monoculture of common vetch was the best. [Conclusion] The monoculture of common vetch can be generalized in the dry land of Xiangxi tobacco-planting areas.

Effect of Mixed Forests of Chinese Fir and Tsoong's Tree on Soil Properties

An investigation and on 13 year old (1984～1996) Chinese fir and Tsoong's tree mixed forests in Jianou City, Fujian Province, China was carried out to compare the influences of different interplanting types of individual tree tree, row row, row strip (three rows) and pure Chinese fir stands on soil properties. Compared with the pure stands of Chinese fir, the mixed stands exerted a positive effect on soil fertility, with increases in soil organic matter, total N, available P and available K. Moreover, improvements were also observed in soil enzymatic activities, aggregate structure, structure stability, status of soil porosity, soil aeration and penetrability in mixed stands. The row row interplanted stands had the best effect on tree growth and soil properties among these mixed forests. In the southern subtropical region, the spreading of the row row mixing model of the two tree species would be helpful to preventing the soil from fertility deterioration caused by successive plantation of Chinese fir.

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

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.

Floristic Composition, Structure and Soil Properties of Mixed Deciduous Forest and Deciduous Dipterocarp Forest: Case Study in Madan Watershed, Myanmar

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 m2) and IVI (27.01) of MDF and Dipterocarpus tuberculatus also composed the highest density (109), dominance (9.02 m2) 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-1 in MDF and 988 and 444 ha-1 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.

A Zinc(Ⅱ) Coordination Framework Based on Terpyridine and 5-Nitroisophthalic Acid Mixed Ligands: Synthesis, Crystal Structure and Fluorescence Property

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.

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

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.

Electronic properties of 2D materials and their junctions

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.

Synthesis, Structure, and Magnetic and Luminescent Properties of Rare Earth Coordination Polymers Constructed from Mixed Dicarboxylates

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.

Studies on Colloidal Properties of Mixed Metal Hydroxide－Clay Aqueous Suspension

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.

Structure and Luminescent Property of a Tetrahedral Silver(Ⅰ) Cluster Complex Based on Phosphor and Sulphur Mixed-ligand System

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.

Syntheses,Structures and Properties of Lanthanide Coordination Polymers Constructed from Mixed Acid

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.

Critical Properties of Mixed Ising Spin System with Different Trimodal Transverse Fields in the Presence of Single-Ion Anisotropy

Within the framework of an effective field approximation, the effects of single-ion anisotropy and different trimodal transverse fields of two sublattices on the critical properties of the mixed spin-1/2 and spin-1 Ising system are investigated on the simple cubic lattice. A smaller single-lon anisotropy can magnify magnetic ordering phases and a larger one can depress magnetic ordering phase for T-Ω1/2 space at low temperatures, while a smaller single-ion anisotropy can hardly change the value of critical transverse field for T-Ω1 space. On the other hand, influences of two different trimodal transverse fields concentrations on tricritical points and magnetic ordering phases take on some interesting results in T-D space. The main reason comes from the common action of single-ion anisotropy, different transverse fields and two trimodal distributions.

Effect of Recycled Mixed Powder on the Mechanical Properties and Microstructure of Concrete

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.

Effects of Calcium Ions on Thermodynamic Properties of Mixed Bilirubin/Cholesterol Monolayers

The mixed monolayer behavior of bilirubin/cholesterol was studied through surface pressure-area （π-A） isotherms on aqueous solutions containing various concentrations of calcium ions. Based on the data of π-A isotherms, the mean area per molecule, collapse pressure, surface compressibility modulus, excess molecular areas, free energy of mixing, and excess free energy of mixing of the monolayers on different subphases were calculated. The results show an expansion in the structure of the mixed monolayer with Ca^2＋ in subphase, and non-ideal mixing of the components at the air/water interface is observed with positive deviation from the additivity rule in the excess molecular areas. The miscibility between the components is weakened with the increase of concentration of Ca^2＋ in subphase. The facts indicate the presence of coordination between Ca^2＋ and the two components. The mixed monolayer, in which the molar ratio of bilirubin to cholesterol is 3：2, is more stable from a thermodynamic point of view on pure water. But the stable 3：2 stoichiometry complex is destroyed with the increase of the concentration of Ca^2＋ in subphase. Otherwise, the mixed monolayers have more thermodynamic stability at lower surface pressure on Ca^2＋ subphase.