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BACKGROUND Composition analysis of copper concentrate is an important method to determine its quality, especially the analysis of the main element copper. Currently, the main analytical methods for the determination of copper content in copper concentrate include iodometry, inductively coupled plasma-optical emission spectrometry (ICP-OES), flame atomic absorption spectrometry (FAAS), X-ray fluorescence spectrometry (XRF), and electrolytic gravimetric methods. OBJECTIVES To ensure the uniformity, accuracy, and reliability of the standard values, interlaboratory comparison activities for the determination of copper, magnesium, lead, and zinc in copper concentrate were organized. METHODS Through the statistical analysis of the test results of the participating laboratories, the technical level and ability of the participating laboratories in the determination of copper, magnesium, lead, and zinc in copper concentrates were evaluated. RESULTS The results showed that most laboratory results were satisfactory, the satisfaction rate of copper in the copper concentrate was 92.9%, and the average satisfaction rate of copper, magnesium, lead, and zinc was 89.0%. The outliers in a few laboratories were mainly attributed to sample pretreatment, lack of understanding and mastering of the analytical methods by the testing personnel, and other related factors, such as the instrument status. CONCLUSIONS Because of incomplete sample decomposition, the alkali leaching method could not be used for pretreatment of copper concentrate. Additionally, the alkali fusion method is not recommended for copper concentrate pretreatment because of its complicated process and matrix interference. Acid dissolution titration is preferred as a pretreatment method for the determination of copper in the copper concentrate. The acid-dissolution ICP-OES method for simultaneous determination of Cu, Mg, Pb, and Zn in the copper concentrate is efficient and rapid with satisfactory results. However, further experiments are required to investigate their stabilities.

To solve the problem of high sheet resistance of transparent conducting films prepared by conventional sol-gel method, IZO films were deposited on sapphire wafer and post treated by pulse laser irradiation. The effects of pulse laser power density on the composition, microstructure, electrical and optical properties of IZO films were analyzed by using energy dispersive X-ray spectroscopy, X-Ray diffraction, Raman spectrometer, four-probe test system and ultraviolet-visible absorption spectroscopy. The results show that the pulse laser does not change the composition of the films, but their electrical properties are improved significantly, which can be ascribed to the change of the film microstructure. With the increase of the pulse laser power density, the structure of the films is transformed from multiphase to amorphous, reducing the effect of deep-level defect at the phase boundary on the scattering and capture of free carriers. When the laser power density is 120 mJ/cm², the high quality IZO films with the sheet resistance of 302 Ω/sq and the transmittance of 77% at 550 nm can be achieved. [ABSTRACT FROM AUTHOR]