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BACKGROUND The dissolution of antimony ore by aqua regia is often incomplete and antimony is easy to hydrolyze in the process of extraction, which leads to inaccurate results. Although atomic fluorescence spectrometry has been widely used in the determination of antimony, it is easy to introduce large dilution error for the determination of high-content antimony (>5%) due to the narrow linear range of the instrument. OBJECTIVES To solve the problem of incomplete dissolution of antimony ores and hydrolysis of antimony in the extraction process, and establish a new method with wider linear range for determination of antimony in antimony ores. METHODS Based on inductively coupled plasma-optical emission spectrometry (ICP-OES), the antimony ore was fully dissolved by hydrofluoric acid, nitric acid and hydrochloric acid, and the hydrolysis of antimony was fully inhibited by the complexation of tartaric acid and antimony. RESULTS The results showed that the solution of the mixed hydrofluoric acid, nitric acid and hydrochloric acid can effectively decompose the silicate components in antimony ores, which can make antimony ores dissolve more completely. The determination result of antimony was better than that of aqua regia, and the detection limit was lower (1.10μg/g). The determination result of antimony obtained by the mixed extraction method of tartaric acid and hydrochloric acid was better than that of aqua regia. The precision of the method was 0.11%-1.11%, which was more stable than that of hydrochloric acid or aqua regia. By using an inductively coupled plasma emission spectrometer, a wider linear range can be obtained by optimizing the spectrum of antimony element analysis, therefore realizing the accurate determination of high-content antimony. CONCLUSIONS This method can dissolve antimony ore quickly and effectively, and avoid the hydrolysis of antimony. The method is confirmed by national first grade standard materials, and the result is in agreement with the certified values. This method is suitable for the analysis of 0.7%-40% antimony in antimony ores.

Open stockyard is widely adopted as coal temporary storage on traditional coal terminal, which leads to the environment pollution. This paper describes the design and realization of the coal silo storage technology application on coal terminal phase-3 project of Huanghua Port. The new technology brings advantages on environmental protection, energy saving and efficiency increasing by downsizing staff. It can provide references for similar projects. [ABSTRACT FROM AUTHOR]

The design of an S-band transmitter is described in detail in this paper and testing results are analyzed. The software simulates body structure and the frequency ranges from the resonance point.In order to realize the miniature, MEMS filter, microwave monolithic integrated circuit and micropackage thin film technics are adopted in the design. The test results show that the flatness of the gain of the S-band transmitter is less than 1 dB, the rejection of spurious signals in of the band is more than 80 dBc,the rejection of local oscillator is more than 57 dBc，and the suppresion of the third-order intermodulation is more than 66 dBc. The dimension of the whole channel is 55 mm×35 mm×14 mm,which has perfect performances and high integration.

Objective: To compare the biomechanical properties of two ultra-strong sutures and suturing methods in panda rope bridge technique (PRBT) application, and provide guidance for clinical selection of suture threads and suture methods., Methods: Forty Achilles tendons from bulls were randomly divided into 4 groups ( n =10) and transected at the 4 cm proximal to the tendon insertion. Groups A and B used Ethibond sutures (USP 5), the proximal end was fixed at the myotendious junction with Krackow sutures and the distal end was fixed through a calcaneus canal. Groups A and B had 4 and 8 threads through the stump plane, respectively. Groups C and D used Ultrabraid sutures (USP 2), the proximal end was fixed at the myotendious junction with Krackow sutures and the distal end was fixed in the calcaneus with two anchors. Groups C and D had 4 and 8 threads through the stump plane, respectively. The dynamic tensile forces of 20-100, 20-200, 20-300, and 20-400 N were tested respectively by using a dynamic tensile testing machine at 0.5 Hz for 250 cycles. After each stage of testing, the gap between stumps was measured with a caliper and the type of suture failure was recorded., Results: After dynamic tensile forces of 20-100 N and 20-200 N, the gaps of the four groups arranged from small to large were groups D, B, C, and A. The differences between groups A and B and groups C and D were significant ( P <0.05). But after dynamic tensile forces of 20-300 N and 20-400 N, the gaps were more than 5 mm in all groups. The suture retention rates of the four groups after dynamic tensile forces of 20-100 N and 20-200 N were all 100%. The suture retention rates of groups A, B, C, and D were 0, 80%, 60%, and 100%, respectively after dynamic tensile forces of 20-300 N. The differences of suture retention rates between group A and groups B and D were significant ( P <0.05). There was no significant difference between groups B, C, and D ( P >0.05). After dynamic tensile forces of 20-400 N, the suture retention rates of groups A, B, C, and D were 0, 50%, 0, and 70%, respectively. There were significant differences between groups A and B and groups C and D ( P <0.05)., Conclusion: Repairing Achilles tendon rupture via PRBT with 8 ultra-strong sutures through the stump plane can meet the mechanical requirements for walking by using ankle boots and heel pads in the early accelerated rehabilitation after operation.