Sol-gel Synthesis and Hydrothermal Crystallization of Indium Germanate

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Machining performance of TiN coatings incorporating indium as a solid lubricant

The machining and wear performance of TiN-coated and patterned carbide inserts incorporating indium as a solid lubricant are reported in this study. Cutting tests were conducted by turning hardened 4340 steel in both lubricated and dry conditions. During turning, periodic flank wear measurements were made. The chips formed during cutting were examined by scanning electron microscopy, as the condition of the chip reflects the conditions obtained during machining. Inserts subject to dry machining were also examined using optical microscopy and X-ray photoelectron spectroscopy to determine the extent of damage on the rake surface as well as the degree of material transfer. The results showed indium to be effective in reducing flank wear during lubricated machining, but little additional benefit of patterning was observed. For dry machining, some degree of improvement was noted in the patterned sample, but the degree of lubricity brought about by the indium coating was not sufficient and the overall flank wear was higher than the lubricated tests. However, the wear and damage on the rake surface along the path of the chip was reduced by the presence of the In-containing microreservoirs. An additional test was conducted using an instrument that simulates temperature effects during machining, and it was found that the lubricity achieved by In coatings is lost above 450 °C. These results suggest that the use of indium is limited to below this temperature, and above this temperature transforms to a less lubricious indium oxide.     

Formation and corrosion of InP/In contacts in hydrochloric acid

Flatband potentials, charge carrier concentrations and their frequency dispersions of p-type and n-type InP in 1.0 M HCl were determined. The cathodic decomposition of InP in this acidic solution is compared with the deposition process of indium from 1.0 M-HCl containing 0.1 M InCl₃. The share of the involved reactions, hydrogen evolution, InP decomposition and indium deposition are investigated. The reaction rates are generally smaller on p-type InP and the reaction speed is much slower but the principal reactions are the same. The kinetics of the indium deposition and dissolution are studied in detail. These reactions are discussed in terms of the preparation of watersplitting photoelectrodes with modified surfaces.     

某高砷难选锌铟矿选矿试验研究

某难选高砷锌铟矿含铟260 g/t、锌1.55%、砷1.15%,铟的存在形式多样、矿物嵌布粒度细微导致该矿铟回收率低、精矿含砷偏高。在矿石性质基础之上采用全硫混合浮选—混合精矿再磨分离的工艺回收原矿中的铟与锌。通过闭路试验获得了锌品位53.09%、铟品位7 112 g/t的锌铟精矿,锌和铟和回收率分别为90.80%与73.91%。精矿中砷含量降低至0.53%,选别指标较好。     

Insights into the simultaneous chronopotentiometric stripping measurement of indium(III), thallium(I) and zinc(II) in acidic medium at the in situ prepared antimony film carbon paste electrode

The simultaneous measurement of microgram per liter concentration levels of indium(III), thallium(I) and zinc(II) at the antimony film carbon paste electrode (SbF-CPE) is demonstrated. The antimony film was deposited in situ on a carbon paste substrate electrode and employed in chronopotentiometric stripping mode in deoxygenated solutions of 0.01 M hydrochloric acid (pH 2). The chronopotentiometric stripping performance of the SbF-CPE was studied and compared with constant current chronopotentiometric stripping and anodic stripping voltammetric operation. In comparison with its bismuth and mercury counterparts, the SbF-CPE exhibited advantageous electroanalytical performance; namely, at the bismuth film electrode, the measurement of zinc(II) was practically impossible due to hydrogen evolution, whereas the mercury film electrode exhibited a poorly developed signal for thallium(I). The SbF-CPE revealed favorable calculated LoDs (3σ) of 1.4 μg L⁻¹ for thallium(I) and 2.4 μg L⁻¹ for indium(III) along with good linear response in the examined concentration range from 10 to 100 μg L⁻¹ with correlations coefficients (R²) of 0.992 for thallium(I) and 0.994 for indium(III) associated with a 120 s deposition time. The chronopotentiometric stripping performance of the SbF-CPE was characterized also by satisfactory reproducibility of 1.62% for indium(III), 3.96% for thallium(I) and 2.11% for zinc(II) (c = 40 μg L⁻¹, n = 11).     

Preparation of In0.5Sc1.5Mo3O12 nanofibers and its negative thermal expansion property

Orthorhombic In_0.5Sc_1.5Mo₃O₁₂ nanofibers were prepared by electrospinning followed by a heat treatment. The effects of post-annealing temperatures on the phase composition, microstructure and morphology were investigated by XRD, SEM, HRTEM and XPS. Negative thermal expansion (NTE) behaviors of the In_0.5Sc_1.5Mo₃O₁₂ nanofibers were analyzed by high-temperature XRD. Results indicate that the as-prepared In_0.5Sc_1.5Mo₃O₁₂ nanofibers show an amorphous structure with smooth and homogeneous shape. The average diameter of the as-prepared In_0.5Sc_1.5Mo₃O₁₂ nanofibers is around 515 nm. Well crystallized orthorhombic In_0.5Sc_1.5Mo₃O₁₂ nanofibers could be prepared after post-annealing at 550 °C for 2 h with an average diameter of about 192 nm. The crystallinity of In_0.5Sc_1.5Mo₃O₁₂ nanofibers gradually improved with the increase of annealing temperature. However, too high post-annealing temperature leads to a damage of sample's fiber structure. The high-temperature XRD results reveal that In_0.5Sc_1.5Mo₃O₁₂ nanofibers show an anisotropic NTE, and the coefficients of thermal expansion (CTEs) along a-axis and c-axis were −5.95 × 10⁻⁶ °C⁻¹ and -3.54 × 10⁻⁶ °C⁻¹, while the one along b-axis is 5.61 × 10⁻⁶ °C⁻¹. The volumetric CTE of In_0.5Sc_1.5Mo₃O₁₂ nanofibers is −3.90 × 10⁻⁶ °C⁻¹ and the linear one is 1.3 × 10⁻⁶ °C⁻¹ in 25–700 °C.     

High-resolution X-ray photoelectron spectroscopy study of InTe thin film in structural phase transition from amorphous to crystalline phase

We investigated the chemical states of InTe thin film in the structural phase transition from the amorphous to the crystalline phase, using high-resolution X-ray photoelectron spectroscopy with synchrotron radiation. We confirmed the structural phase transition by transmission electron microscopy. Clean amorphous InTe (a-InTe) free of oxygen impurity was obtained after Ne⁺ ion sputtering at the ion beam energy of 1 kV for 1 h. Additionally, we obtained crystalline InTe (c-InTe) from clean a-InTe by annealing at 250 °C in an ultra-high vacuum. During the transition to the crystalline phase, the binding energy of the Te 4d core-level was unchanged, but the peak width was somewhat wider than in the amorphous phase. In the case of the In 4d core-level, the chemical shift was 0.1 eV at the higher binding energy between the amorphous and crystalline phases. The valence band maximum was shifted at the higher binding energy of 0.34 eV. We assumed that the Te atom was almost fixed and that the In atoms moved in the tight binding energy state to the center of the 4-Te atoms.     

In-situ monitoring of InP(100) and GaP(100) interfaces and characterization with RDS at 20 K

MOVPE-preparation of highly ordered InP(100) and GaP(100) surfaces was monitored with in-situ reflectance difference spectroscopy (RDS). Specific ordered P-terminated and ordered cation-terminated surface reconstructions were identified with specific structured RD spectra with the highest peaks. After contamination-free transfer of the samples to UHV, RDS measurements were performed also at 20 K. The experimental RD spectrum for the In-terminated, (2×4) reconstructed InP(100) surface shows a remarkable similarity to a recently published theoretical spectrum, whereas there is only moderate similarity between the experimental RD spectrum for the (2×4) reconstructed Ga-terminated GaP(100) surface and a recently proposed theoretical spectrum.     

Effect of surface roughness and surface modification of indium tin oxide electrode on its potential response to tryptophan

The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2 nm of R_a evaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with R_a values ranging between ∼2 and ∼3 nm but not for those with R_a of ∼1 nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface.     

锑化铟锭条的全自动霍耳效应测试系统

为了解决InSb锭条霍耳效应的测试任务‘研制出一套微机控制的全自动测试系统,可对各种截面形状的半导体锭条进行无破坏性的霍耳效应测量。本系统包括一台HP-85型计算机和705型扫描器、220型恒流源以及195型数字多用表,一个自制的多功能测试单元。本文叙述了系统的测量原理,分析了系统中各部分仪器和机构的连接配合控制及其具有的功能,介绍了抗干扰问题的解决方法并进行了误差分析。进行了大量的室温下的测量,并与本征理论值比较,证明系统的测量精度与误差分析是相一致的。此系统大大提高了InSb锭条的测量速度和精度,是研究InSb材料(包括其他半导体材料)十分有用的工具。