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1.

Abstract  

The density and surface tension of binary In–Sn and ternary Cu–In–Sn alloys have been measured by a sessile-drop method. Decrease of the density and of the surface tension was observed with rising temperature. With increased Sn content in the alloys, the density increased while the surface tension reduced slightly. Addition of Cu could significantly increase the density and surface tension in the Cu–In–Sn system. The surface tension of the Cu–In–Sn alloys was also calculated by means of Butler’s equation, and compared with experimental values, showing good agreement.  相似文献   

2.
The standard enthalpy of formation of several Pd–M alloys (M = In, Sn and Zn) has been measured using a high temperature direct drop calorimeter. The reliability of the calorimetric results has been determined and supported by using different analytical techniques: light optical microscopy, scanning electron microscopy equipped with electron probe microanalysis (EPMA with EDS detector) and X-ray powder diffraction analysis. The values of ΔfH (kJ/mol atoms) for the following phases were obtained for the formation in the solid state at 300 K: PdIn (49 at.%In): ?69.0 ± 1.0; Pd2In3 ?57.0 ± 1.0; Pd3In7: ?43.0 ± 1.0; PdSn2: ?50.0 ± 1.0; Pd2Zn9 (77 at.%Zn): ?33.7 ± 1.0; Pd2Zn9 (78 at.%Zn): ?34.0 ± 1.0; Pd2Zn9 (80 at.%Zn): ?35.0 ± 1.0. The results show exothermic values which increase from the Pd–Zn to the Pd–Sn and Pd–In systems; the data obtained have been discussed in comparison with those available in literature.  相似文献   

3.
The mixed oxide compounds, (M1/2Sb1/2Sn)O4, M = In and Fe are prepared by the high-temperature solid-state reaction, at 800 °C for M = In and at 1,150 °C for M = Fe. High-energy ballmilling is used to reduce the particle size to nm-range. The compounds are characterized by X-ray diffraction, Rietveld refinement, scanning electron microscopy, and Brunauer–Emmett–Teller surface area methods. The Li-storage and cycling properties of the bare and ballmilled compounds are evaluated by galvanostatic cycling at ~0.15 C and in the voltage ranges 0.005–1.0 and 0.005–1.2 V vs. Li up to 50 (or 100) cycles and by cyclic voltammetry (CV) at room temperature. Effect of electrode heat treatment and carbon nanotube (CNT) addition is also studied. Initial reversible capacities in the range 425–550 mAh g?1 are observed depending on the metal (M) upper cut-off voltage, CNT content and electrode heat treatment. Ballmilled (In1/2Sb1/2Sn)O4 showed a stable capacity of 445 mAh g-1 up to 30 cycles and 5 % capacity fading after 50 cycles. In all other cases, capacity fading is observed ranging from 9 to 60 %. The CV showed that the main cathodic and anodic peaks occur at 0.15–0.25 V and ~0.5 V vs. Li, respectively, for both M. The reaction mechanism involves alloying–de-alloying reactions of Sn and In with Li3Sb or Fe acting as conducting matrix, and corroborated by the ex-situ X-ray diffraction data on (In1/2Sb1/2Sn)O4.  相似文献   

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采用全势线性缀加平面波(FPLAPW)方法, 在广义梯度近似(GGA)+自旋轨道耦合(SOC)+自旋极化(SP)下计算了具有AuCu3构型的Pu3M和PuM3 (M=Ga, In, Sn, Ge)化合物的平衡结构、电子结构和形成热. 计算的晶格常数与实验值符合得很好; 态密度分析表明Pu 和M 原子轨道间的杂化作用决定于Pu 6d-Pu 5f、Mp-Pu 6d和Msp-M sp轨道杂化之间的竞争, 而这种竞争又依赖于M的含量; 电负性差和电子杂化效应是影响Pu3M和PuM3化合物形成热和稳定性的两个重要因素, 电负性差越大, M的s、p带中心距费米能级越远, Pu3M(PuM3)化合物的形成热越负, 稳定性越高.  相似文献   

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A theoretical formalism that links thermodynamic properties to transport properties has been used to study the viscosity of Sn–Zn and In–Zn liquid alloys at various temperatures. The formalism was successful at describing the thermodynamic properties of these alloys and showed a better estimation of the viscosity of the Sn–Zn alloy than that of the In–Zn alloy.  相似文献   

9.
利用卡尔曼滤波(KF)技术,对互相干扰的Sn(Ⅳ),Pb(Ⅱ),In(Ⅲ),Cd(Ⅱ)体系进行了定量测试研究,在5.00×10^5~3.00×10^-4mol.L^-1的浓度范围内,各组分测试的相对误差为-4.0%~3.85%,对大理石抛光粉管理样中的Sn(Ⅳ),Pb(Ⅱ)进行了测定,结果与ICP-AES结果表明,回收率在95.0%~104%之间,为保证KF的精度,使用两个监控出口。数据说明效果良  相似文献   

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Gas diffusion electrodes (GDEs), including GDE-In0.90Sn0.10, GDE-In0.47Sn0.53 and GDE-In0.22Sn0.78, were prepared by electrodeposition of In–Sn alloys on carbon fiber paper, and then used to explore the electroreduction of CO2 to formate in aqueous solution. Compared with commercial indium or Sn foil catalysts, the GDE-In0.90Sn0.10 electrode in particular is shown to have excellent catalytic performance towards electroreduction of CO2 to formate, with a high Faradaic efficiency (~ 92%). More importantly, the catalytic activity of GDE-In0.90Sn0.10 remained reasonably stable over a 22-hour period of electrolysis, and a relatively high electrolytic current density (15 mA cm 2) was obtained in an aqueous medium, demonstrating its potential for electrochemical reduction of CO2 to formate.  相似文献   

12.
Activities of components in liquid Al–Ga and In–Sn alloys, the separation coefficients and vapour–liquid phase equilibrium in vacuum distillation were predicted using the molecular interaction volume model as a function of the activity coefficients. The results indicated that both Al and In are preferentially volatilised into vapour phase while Ga and Sn remain in residue. Similarly, we found that both the mass fraction and the content of Al and In in vapour phase increase as distillation temperature increases such that when the content of Al is 0.005985 wt% and In is 0.004141 wt% in vapour phase, respectively, in liquid phase, it was 70 wt% at T = 1073 K for both. The calculated values of activity and activity coefficients at various temperatures are presented. Comparison of the predicted values with experimental data indicates good agreement, thus verifying from statistical thermodynamics viewpoint that the model is stable and reliable.  相似文献   

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14.
基于剑桥晶体数据库中同配配合物的Sn(Ⅱ)-X和Sn(Ⅳ)-X (X=O,S,N,C,P,As,Se,Te,F,Cl,Br,I)键长数据,采用键价参数B=0.037 nm拟合得到Sn(Ⅱ)-X和Sn(Ⅳ)-X的键价参数R0,这样拟合的经验参数R0中有一些是首次推出.本文所报道的Sn(Ⅱ)-O键基于B=0.037 nm的R0值(0.1956 nm)可适用于多数Sn(Ⅱ)呈各种配位数时的氧化态指定,而文献报道的B=0.055 nm和R0=0.1859 nm主要对于低配位的情况能取得Sn(Ⅱ)原子价态指定的较好结果.本研究证明,进一步研究键价参数对键价和(BVS)计算至关重要的那些可能的因素实乃当务之急.  相似文献   

15.
The stannides RE2Au3Sn6 (RE = La, Ce, Pr, Nd, Sm) were synthesized from the elements by arc-melting. Small single crystals were grown by annealing samples in sealed tantalum tubes in an induction furnace with a special annealing sequence. The polycrystalline phases were characterized through their X-ray powder diffraction pattern. The structures of Ce2Au3Sn6, Pr2Au3Sn6, and Nd2Au3Sn6 were refined from single-crystal X-ray diffractometer data. The RE2Au3Sn6 stannides crystallize with the orthorhombic La2Zn3Ge6 type, space group Cmcm. The basic structural building units are Au1@Sn4 tetrahedra and Au2@Sn5 square pyramids. These units are condensed to layers and the structure can be described by a simple stacking of tetrahedral and pyramidal layers with the rare earth cations in between. Temperature dependent susceptibility studies indicate that all rare earth atoms are in the trivalent oxidation state, as their effective magnetic moments match the expected values of the free RE3+ ions. Pr2Au3Sn6 and Nd2Au3Sn6 exhibit antiferromagnetic ordering at TN = 6.3(1) and 6.7(1) K. Investigations of the electrical resistivity of La2Au3Sn6 and Ce2Au3Sn6 confirmed that these compounds are metallic, for La2Au3Sn6 a lower resistivity was observed, in line with the absence of screening unpaired electrons. 119Sn Mössbauer spectra for La2Au3Sn6, Ce2Au3Sn6, Pr2Au3Sn6 and Nd2Au3Sn6 show a complex superposition of three sub-spectra which can be differentiated through their distinctly different quadrupole splitting parameters. The isomer shifts (1.87 to 2.22 mm · s–1) indicate significant s electron density at the tin nuclei.  相似文献   

16.
基于剑桥晶体数据库中同配配合物的Sn(Ⅱ)―X和Sn(Ⅳ)―X(X=O,S,N,C,P,As,Se,Te,F,Cl,Br,I)键长数据,采用键价参数B=0.037nm拟合得到Sn(Ⅱ)―X和Sn(Ⅳ)―X的键价参数R0,这样拟合的经验参数R0中有一些是首次推出.本文所报道的Sn(Ⅱ)―O键基于B=0.037nm的R0值(0.1956nm)可适用于多数Sn(Ⅱ)呈各种配位数时的氧化态指定,而文献报道的B=0.055nm和R0=0.1859nm主要对于低配位的情况能取得Sn(Ⅱ)原子价态指定的较好结果.本研究证明,进一步研究键价参数对键价和(BVS)计算至关重要的那些可能的因素实乃当务之急.  相似文献   

17.
用可控湿化学共沉淀法研制了In2O3-SnO2纳米复合物,通过控制金属盐浓度、阳离子比、沉淀pH值和老化时间,制得化学均一的两元复合物,引入适量的第三组分TiO2制得三元纳米复合氧化物,研究了TiO2添加对材料气敏和CH4催化反应活性的影响,用各种分析方法对复合物进行物性和结构表征,从对CH4气敏和催化活性测定的结果表明,两元25%In2O3-75%SnO2复合物和三元(25%In2O3-75%SnO2)-20%TiO2复合物对CH4具有较好的灵敏度和催化活性,两者有相同变化趋势,也提高了对CO的选择性,再经过掺杂对基质进行结构调变和表面修饰,进一步提高气敏和催化活性。用程序升温吸-脱附(TPD)实验和X-射线光电子能谱(XPS)分析研究了纳米复合物表面对待测气体和氧的吸脱附行为和组分间电子和化学的相互作用,探讨了气敏机制。  相似文献   

18.
Zusammenfassung Nb3Sn und Mo3Al bilden eine lückenlose Mischreihe. Nb3Sn löst bei 1600°C rd. 60 Mol% Ti3Sn, 30 Mol% Zr(3)Sn, 40 Mol% Hf(3)Sn bzw. 50 Mol% Nb(3)Si.Mit 5 Abbildungen  相似文献   

19.
Yue CY  Lei XW 《Inorganic chemistry》2012,51(4):2461-2471
Three new rare-earth (RE) niobium stannides, namely, Sc(2)Nb(4-x)Sn(5) (x = 0.37, 0.52), YNb(6)Sn(6), and ErNb(6)Sn(5), have been obtained by reacting the mixture of corresponding pure elements at high temperature and structurally characterized by single-crystal X-ray diffraction studies. Sc(2)Nb(4-x)Sn(5) crystallizes in the orthorhombic space group Ibam (No. 72) and belongs to the V(6)Si(5) type. Its structure features a three-dimensional (3D) network composed of two-dimensionally (2D) corrugated [Nb(2)Sn(2)] and [Nb(2)Sn(3)] layers interconnected via Nb-Sn bonds, forming one type of one-dimensional (1D) narrow tunnels along the c axis occupied by Sc atoms. YNb(6)Sn(6) crystallizes in the hexagonal space group P6/mmm (No. 191) and adopts the HfFe(6)Ge(6) type, and ErNb(6)Sn(5) crystallizes in the trigonal space group R3m (No. 166) and belongs to the LiFe(6)Ge(5) type. Their structures both feature 3D networks based on 2D [Nb(3)Sn], [Sn(2)], and [RESn(2)] layers (RE = Y, Er). In YNb(6)Sn(6), one type of [Nb(3)Sn] layer is interconnected by [Sn(2)] and [YSn(2)] layers via Nb-Sn bonds to form a 3D network. However, in ErNb(6)Sn(5), two types of [Nb(3)Sn] layers are interlinked by [Sn(2)] and [ErSn(2)] layers via Nb-Sn bonds into a 3D framework. Electronic structure calculations and magnetic property measurements for "Sc(2)Nb(4)Sn(5)" and YNb(6)Sn(6) indicate that both compounds show semimetallic and temperature-independent diamagnetic behavior.  相似文献   

20.
An experimental study of the temperature dependences of the surface tension of liquid high-entropy equiatomic alloys of a Cu–Sn–Bi–In–Pb system is conducted. Measurements are made within the temperature range of t L to 1300°C in the mode of heating and subsequent cooling of a sample. Overcooling of a melt prior to crystallization is detected. The depth of overcooling grows along with the number of components in the melt, while the temperature coefficient of surface tension falls. The experimental results qualitatively interpreted within the concepts of the specific surface entropy of a liquid.  相似文献   

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