INFLUENCE OF Nb ON THE MICROSTRUCTURE OF F_(e76.5-x) C_(u1)Nb_(x) Si_(13.5)B_9 NANOCRYSTALLINE STUDIED BY M■SSBAUER SPECTROCOPY

测量制备态和退火的Ｆｅ７６．５－ｘＣｕ１ＮｂｘＳｉ１３．５Ｂ９（ｘ＝０．１０、３．０、５．２、７．２）合金Ｍｏｓｓｂａｕｅｒ谱，结果表明，晶化后Ｎｂ、Ｂ等元素向晶界区扩散，在残余非晶形成了富Ｎｂ、Ｂ区和Ｎｂ、Ｂ区、Ｎｂ抑制非昌相的晶化和Ｆｅ２Ｂ相的析出，并对磁织构有一定的影响。     

Fe—40Al及其含Mn或Ti合金的Mossbauer谱

用Ｍｏｓｓｂａｕｅｒ谱研究了Ｂ２结构金属间化合物Ｆｅ－４０Ａｌ及其加Ｍｎ或Ｔｉ量分别为１，５，１０ａｔ．－％的合金．在室温下，Ｆｅ－４０Ａｌ及其合金的Ｍｏｓｓｂａｕｅｒ谱均接近单峰谱线，Ｆｅ原子无明显磁矩对加入第三组元的Ｆｅ—４０Ａｌ合金的Ｍｏｓｓｂａｕｅｒ谱用最小二乘法拟合为两条洛仑兹曲线之和，认为Ｍｎ原子既占据Ｆｅ原子位置，也占据Ａｌ原子位置；而Ｔｉ原子优先占据Ｆｅ原子位置，超过５ａｔ．－％时，才有少量Ｔｉ原子占据Ａｌ原子位置．     

Fe—40La及其含Mn或Ti合金的Mossbauer谱

用Ｍｏｓｓｂａｕｅｒ谱研究了Ｂ２结构金属间化合物Ｆｅ－４０Ａｌ及其加Ｍｎ或Ｔｉ量分别为１，５，１０ａｔ．－％的合金，在室温下，Ｆｅ－４０Ａｌ及其合金的Ｍｏｓｓｂａｕｅｒ谱均接近单峰谱线，Ｆｅ原子无明显磁矩。对加入第三组元的Ｆｅ－４０Ａｌ合金的Ｍｏｓｓｂａｕｅｒ谱用最小二乘法拟合为两条洛仑兹曲线之和，认为Ｍｎ原子既占据Ｆ原子位置，也占据Ａｌ原子位置；而Ｔｉ原子优先占据了Ｆｅ原子位置，超过５ａｔ．－％     

STUDY FOR MECHANICAL ALLOYING OF Fe─M BY MOSSBAUER SPECTROSCOPY

将Ｆｅ－Ｍ（Ｍ＝Ｃ５ＳｉＯ２Ａｌ２Ｏ３）混合物在Ａｒ中高能球磨５６ｇ后测量Ｍｏｓｂａｕｅｒ谱，结果表明，（Ｆｅ）２－（ＳｉＯ２）１仍为Ｆｅ和ＳｉＯ２的机械混合物：（Ｆｅ）６－（Ｃ）３已完全合金化，生成两种Ｆｅ３Ｃ；（Ｆｅ）２－（Ａｌ２Ｏ３）１则成为Ｆｅ（７３％），尖晶石型的ＦｅＡｌ２Ｏ４）２２％），ｑｑｎｔＦｅ的团聚族（５％）和Ａｌ２Ｏ３的混合物。     

Fe（OH）3中微量金属离子对水热合成α—Fe2O3粒径的影响

本文研究了某些金属离子（Ａｌ＾３＋、Ｍｎ＾２＋、Ｚｎ＾２＋、Ｃｒ＾２＋、Ｎｉ＾２＋、Ｃｏ＾２＋）Ｆｅ（ＯＨ）３凝胶经水热法合成的α－Ｆｅ２Ｏ３微粉颗粒大小的影响。研究结果出现，随着金属离子的浓度在一定范围内（０．０１０－０．０５０ｍｏｌ·Ｌ＾－１）的增加，α－Ｆｅ２Ｏ３颗粒有减小的趋势。其中加入Ｃｏ＾２＋（０．０５０ｍｏｌ·Ｌ＾－１）、Ｍｎ＾２＋（０．１００ｍｏｌ·Ｌ＾－１）可以得到粒径为７５ｎｍ     

立方A^4＋M^5＋2O7型化合物与新型负热膨胀材料

概述了立方Ａ＾４＋Ｍ＾５＋２Ｏ７型化合物的结构特点，讨论了ＡＶ２－ｘＰｘＯ７型（Ａ＝Ｚｒ或Ｈｆ；ｘ＝０．１～１．２）及其部分取代的Ａ＾４＋１－ｙＢ＾４＋ｙＶ２－ｘＰｘＯ７型（Ｂ＝Ｔｉ，Ｃｅ，Ｔｈ，Ｕ，Ｍｏ，Ｐｔ，Ｐｂ，Ｓｎ，Ｇｅ或Ｓｉ；ｙ＝０．１～０．４）和Ａ＾４＋１－ｙＣ＾１＋ｙＤ＾３＋ｙＶ２－ｘＰｘＯ７型（Ｃ为碱金属元素，Ｄ为稀土金属元素）材料的负热膨胀性能。     

一个与准晶相关的新Al—Cu相

本文报道一个新Ａｌ－Ｃｕ相，具有正交结构，空间群Ｆｄｄｄ，点阵常数为：ａ＝０．８１６６ｎｍ，ｂ＝０．９９９５ｎｍ，ｃ＝１．４１４９ｎｍ，表达式为Ａｌ４３．２Ｃｕ５６．８，该相与Ａｌ－Ｃｕ－Ｆｅ准晶的价电子浓度相同，是一个由ＣｓＣｌ结构衍生的类似相。     

超负磁致伸缩晶体Sm—Fe,Sm—Dy—Fe和Sm—Dy—Fe—Al的研究

本文研究了轻稀土负磁致伸缩ＳｍＦｅｘ（１．４０≤ｘ≤１．９４），ＳｍｘＤｙ１－ｘＦｅｙ（０．８４≤ｘ≤０．９２，１．８０≤ｙ≤１．９０），Ｓｍ０．９０Ｄｙ０．１０（Ｆｅ０．９５Ａｌ０．０５）１．８０晶体的制备，热处理及磁学性能，发现ＳｍＦｅｘ合金的λ－ｘ曲线存在两个峰值，峰值的ｘ点热处理发生的变化有一定的规律性，还比较了热处理前后，Ｓｍ－Ｆｅ、Ｓｍ－Ｄｙ－Ｆｅ和Ｓｍ－Ｄｙ－Ｆｅ－Ａｌ的相组成对性能     

一个与准晶相关的新Al－Cu相

本文报道一个新Ａｌ－Ｃｕ相具有正交结构，空间群Ｆｄｄｄ．点阵常数为：ａ＝０．８１６６ｎｍ，ｂ＝０．９９９５ｎｍ，ｃ＝１．４１４９ｎｍ，表达式为Ａｌ４３．２Ｃｕ５６．８．该相与Ａｌ－Ｃｕ－Ｆｅ准晶的价电子浓度相同，是一个由ＣｓＣｌ结构衍生的类似相．     

Fe73.5Cu1Mo3Si13.5B9微晶软磁合金的结构及其对磁性的影响

对Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１３．５Ｂ９微晶软磁合金的结构及其对合金磁性的影响了研究，结果表明，在最佳磁性能下，晶相点阵常数ａ＝０．２８４３ｎｍ，相当于Ｆｅ（Ｓｉ）固溶体中含Ｓｉ％（ｍｏｌ／ｍｏｌ）：１８－２０，体积百分数Ｖ＝７４．８％，晶粒尺寸Ｄ＝１４．６ｎｍ；残余非晶层厚度δ＝１．２３ｎｍ；当Ｔ退火≥５６０℃时明显有Ｆｅ－Ｂ化合物析出。Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１３．５Ｂ９合金的磁性不仅与     

Band offset of the In2S3/indium tin oxide interface measured by X-ray photoelectron spectroscopy

In₂S₃ thin films have been grown on Indium Tin Oxide (ITO) by Chemical Spray Pyrolysis. The structural and physical-chemical properties of the films have been investigated by means of X-ray Diffraction and X-ray Photoelectron spectroscopy (XPS). The valence band discontinuity at the In₂S₃/ITO interface has been determined by XPS resulting in a value of 1.9 ± 0.2 eV. Consequently, the conduction band offset has been estimated to be 1.0 ± 0.4 eV.     

Glass formation tendency in the system SeO2-Ag2O-B2O3

The glass formation regions in the system SeO₂-Ag₂O-B₂O₃ have been determined using the melt quenching method of evacuated silica ampoules. The structural units forming the amorphous network have been established by IR spectroscopy. The presence of SeO₃ (ν = 820 cm⁻¹; 760-750 cm⁻¹), BO₃ (ν = 1340, 1270 cm⁻¹) and BO₄ (ν = 1050 cm⁻¹) units has been confirmed. Crystallization of Ag₂SeO₃ only has been observed in a wide concentrate region near the glass formation boundary. A model explaining the unsatisfactory glass formation ability in the system investigated has been developed. It has been suggested that Ag⁺ ions are predominantly located near the selenite units, which stimulates the formation of isolated SeO₃ groups. The transformation of BO₃ into BO₄ units is hindered by the absence of free Ag⁺ ions near the borate units.     

Super H2O-barrier film using Cat-CVD (HWCVD)-grown SiCN for film-based electronics

“Super H₂O-barrier film” with a water vapor transmission rate (WVTR) less than 1 mg/m²/day has been developed. The barrier layer is a single layer of amorphous SiCN grown by organic Cat-CVD (O-Cat-CVD) with a thickness of 100 nm. SiCN has been grown by using a gas mixture of monomethylsilane (MMS; Si (CH₃)H₃), NH₃ and H₂ on polyethylene-naphthalate (PEN) film substrates. It has been found that the WVTR drastically depends on the W-filament temperature of O-Cat-CVD. The WVTR changed from 5 × 10⁻¹ to 1 × 10⁻³, corresponding to the W-filament temperature increase from 1100 to 1200 C. We have recently succeeded in developing the “super H₂O-barrier film” by the coating of single layers of SiCN for both sides of the PEN film without using the widely used polymer/inorganic multilayer coating. The both-side coating has been found to be crucial to avoid the H₂O penetration into PEN films and also to avoid the breakdown of the SiCN/PEN interface caused by the H₂O accumulation at the interface.     

Reactive magnetron sputtering from a composite target for large area BaPbO3 thin film electrode

Radio frequency reactive magnetron sputtering from a composite target made of PbO pellets uniformly positioned on a metallic Ba disc has been utilized for BaPbO₃ electrode deposition on 150 mm Si wafers. The reactive sputtering process has been analyzed in relation to sputtering parameters for composite targets with different percentage of PbO coverage. The process optimization method for in situ crystallized BaPbO₃ thin film fabrication has been emphasized. The growth of BaPbO₃ films has been discussed from the viewpoint of the BaO-PbO phase diagram and thermodynamics of Ba_n + 1Pb_nO_3n + 1 (n = 1, 2, ∞) phase formation. The microstructure analysis of the deposited films has been performed with atomic force microscopy and wide-angle X-ray diffraction (XRD) techniques. The grazing angle XRD measurements reveal the formation of a Ba₂PbO₄ phase in the film fabricated at 450 °C. The Ba₂PbO₄ phase content decreases with decreasing substrate temperature. The BaPbO₃ film deposited at a substrate temperature of 430 °C on naturally oxidized (001) Si wafers shows an electrical resistivity of 1.13 mΩ·cm. The BaPbO₃ films deposited on SiO₂ (native oxide)/Si wafer do not exhibit a preferred orientation whereas use of (111) Pt/SiO₂/Si substrate results in highly (111)-oriented films.     

Neutron diffraction investigation of a tellurite-tungstate glass

The short range atomic order of a 20 mol% WO₃-TeO₂ glass has been investigated. The alteration of the stereochemical polyhedra characteristics have been studied and correlation with the model RDF_partial (radial distribution function) and RDF_total for TeO₂ and WO₃ glass has been carried out. A structural interpretation of the influence of the modifier on the P1, P2 and P3 peaks location has also been carried out. A comparison of RDF_partial, and RDF_total, with RDF_exp curve of the glass has been accomplished. Stability of the 0-0 distances (peak P2) has been established as well as a broadening effect at Te-Te, Te-second 0 distances (peak P3). The Te-Te atomic distances are most sensitive towards glass transition. A structural model based on TeO₄, WO₄ and WO₆ polyhedra has been presented.Part of the results in this investigation were reported at a poster session on the XIII International Congress on Glass, Hamburg, 4–9 July 1983.     

Amperometric hydrogen peroxide biosensor based on cobalt ferrite-chitosan nanocomposite

A novel H₂O₂ biosensor based on horseradish peroxidase (HRP) immobilized into CoFe₂O₄-chitosan nanocomposite has been developed for the detection of hydrogen peroxide. The nanocomposite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). HRP has been entrapped into CoFe₂O₄-chitosan nanocomposite film and the immobilized enzyme could retain its bioactivity. This biosensor exhibited a fast amperometric response to hydrogen peroxide. The linear range for H₂O₂ determination was from 3 × 10^− 2 to 8 mM, with a detection limit of 2 × 10^− 3 mM based on S/N = 3. The response time of the biosensor was 4 s. The effects of the pH and the temperature of the immobilized HRP electrode were also studied.     

Thin film solar cells based on the ternary compound Cu2SnS3

Alongside with Cu₂ZnSnS₄ and SnS, the p-type semiconductor Cu₂SnS₃ also consists of only Earth abundant and low-cost elements and shows comparable opto-electronic properties, with respect to Cu₂ZnSnS₄ and SnS, making it a promising candidate for photovoltaic applications of the future. In this work, the ternary compound has been produced via the annealing of an electrodeposited precursor in a sulfur and tin sulfide environment. The obtained absorber layer has been structurally investigated by X-ray diffraction and results indicate the crystal structure to be monoclinic. Its optical properties have been measured via photoluminescence, where an asymmetric peak at 0.95 eV has been found. The evaluation of the photoluminescence spectrum indicates a band gap of 0.93 eV which agrees well with the results from the external quantum efficiency. Furthermore, this semiconductor layer has been processed into a photovoltaic device with a power conversion efficiency of 0.54%, a short circuit current of 17.1 mA/cm², an open circuit voltage of 104 mV hampered by a small shunt resistance, a fill factor of 30.4%, and a maximal external quantum efficiency of just less than 60%. In addition, the potential of this Cu₂SnS₃ absorber layer for photovoltaic applications is discussed.     

Stability of 8-hydroxyquinoline aluminum films encapsulated by a single Al2O3 barrier deposited by low temperature atomic layer deposition

100 nm thick 8‐AlQ₃ films deposited onto silicon wafers have been encapsulated by mean of low temperature atomic layer deposition of Al₂O₃ (20 nm). Investigation of the film evolution under storage test as harsh as 65 °C/85% RH has been investigated up to ~ 1000 h and no severe degradation could be noticed. The results have been compared to raw AlQ₃ films which deteriorate far faster in the same conditions. For that purpose, fluorescence measurements and atomic force microscopy have been used to monitor the film evolution while transmission electron microscopy has been used to image the interface between AlQ₃ and Al₂O₃. This concept of bilayer AlQ₃/Al₂O₃ barrier films has finally been tested as an encapsulation barrier onto an organic light-emitting diode.     

Electrical resistivity of nickel-rich nickel-chromium alloys between 4 and 300 K

Electrical resistivity of Ni–Cr alloys containing 5.5, 11.3, 15.7, 16.8, 19.4, 22.0, 24.6, and 27.0 at % Cr has been measured as a function of the absolute temperatureT between 4 and 300 K. The sample with the Cr content of 22.0 at % exhibits a small minimum at about 10 K. No minimum has been observed in any other of the above samples, although an anomalousT dependence has been found in alloys containing 15.7, 16.8, and 19.4 at % Cr. The minimum has been discussed from the viewpoint of the Béal-Monod theory for the Kondo effect in concentrated systems and the mechanism by Greig and Rowlands based on aT-dependent decrease of the impurity electrical resistivity. It is concluded that the minimum in the Ni–Cr system is still a phenomenon which is not well understood at the present time.     

Electronic parameters and top surface chemical stability of RbPb2Br5

The RbPb₂Br₅ crystal has been grown by Bridgman method. The electronic structure of RbPb₂Br₅ has been measured with XPS for a powder sample. High chemical stability of RbPb₂Br₅ surface is verified by weak intensity of O 1s core level recorded by XPS and structural RHEED measurements. Chemical bonding effects have been observed by the comparative analysis of element core levels and crystal structure of RbPb₂Br₅ and several rubidium- and lead-containing bromides using binding energy difference parameters Δ_Rb = (BE Rb 3d − BE Br 3d) and Δ_Pb = (BE Pb 4f_7/2 − BE Br 3d).