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1

The Bending, Impact Fracture Behavior and Characteristics of Stainless Steel Clad Plates with Different Rolling Temperature

An Q., Fan K. Y., Ge Y. F., Liu B. X., He J., Wang S., Chen C. X., Ji P. G., Tolochko O.

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 1

229--239

EN

The interface characteristics, bending and impact behavior, as well as fracture characteristics of stainless steel clad plates fabricated by vacuum hot rolling at different rolling temperatures of 1100°C, 1200°C and 1300°C are investigated in detail. The interface bonding strength is gradually increased with the increasing rolling temperature due to the sufficient diffusion behavior of alloy element. The bending toughness and impact toughness are gradually decreased, while the bending strength increase with the increase of the rolling temperature, which is attributed to mechanisms of matrix softening and interface strengthening at high rolling temperature. Due to the weak interface at 1100°C, the bending and impact crack propagation path was displaced by delamination cracks, which in turn lead to reduction in stress intensity of the main crack, playing an effective role in toughening the stainless steel clad plates. Moreover, the impact fracture morphologies of clad plates show a typical ductile-brittle transition phenomenon, which is attributed to the matrix softening behavior with the increasing rolling temperature.

2

Development micellar HPLC method for simultaneous determination of ephedrine, pseudoephedrine, and methylephedrine in Ephedra Herb and traditional Chinese medicinal preparations

Dong Y. M., An Q., Lu N. W., Li N.

Acta Chromatographica

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2015

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Vol. 27, no. 2

355--372

EN

A micellar high-performance liquid chromatography (HPLC) method has been described for simultaneous determination of ephedrine, pseudoephedrine, and methylephedrine in Ephedra Herb and two traditional Chinese preparations. The separation and determination of ephedrine, pseudoephedrine, and methylephedrine were performed using a mobile phase containing 1.75 × 10−1 mol•L−1 sodium dodecyl sulphate and 0.02 mol•L−1 potassium hydrogen phosphate with 10% (v/v) methanol at pH 3.0, running at 1.5 mL•min−1 by a Venusil XBP C18 (250 × 4.6 mm, 5 μm) column at 40 °C. The detected wavelength was set at 210 nm. The method was validated according to the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines. The main analytical parameters were linearity (r > 0.9990), intra- and inter-day precisions (relative standard deviation [RSD %], 0.33–1.63, and RSD %, 1.26–2.20, respectively), limit of quantifications [LOQs], and limit of detections [LODs] (2.6 × 10−4 and 7.8 × 10−5 mg•mL−1 for ephedrine, 6.8 × 10−4 and 2.0 × 10−4 mg•mL−1 for pseudoephedrine, and 5.0 × 10−4 and 1.5 × 10−4 mg•mL−1 for methylephedrine). RSDs of recoveries were <5.5% in the three samples. Based on the optimized chromatographic conditions and the eluted orders, a model of separation mechanism for the analytes was established. The results indicated that the proposed method was an accurate, “green” and cheap method.

3

A 128-channel high precision time measurement module

Kang L., Zhao L., Zhou J, Liu S., An Q.

Metrology and Measurement Systems

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2013

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Vol. 20, nr 2

275--286

EN

In the external target experiment for heavy ion collisions in the HIRFL-CSR, Multi-Wire Drift Chambers are used to measure the drift time of charged particles to obtain the track information. This 128-channel high precision time measurement module is designed to perform the time digitization. The data transfer is based on a PXI interface to guarantee a high data rate. Test results show that a 100 ps resolution with a data transfer rate up to 40 MBps has been achieved; this module has also been proven to function well with the detector through a commissioning test.

4

Infrared thermography as a new method for quality control of sheet metal parts in the press shop

An Q., Hortig D., Merklein M.

Archives of Civil and Mechanical Engineering

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2012

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Vol. 12, no. 2

148--155

EN

Active dynamic thermography was proved to be a new alternative for crack detection. To achieve zero failure sheet metal production in the press shop, this method was investigated for different steel components, which were directly collected from series production. And the cracks in the presented specimens differ in length and in depth, and a series study on these surface cracks is executed. The crack detection capabilities of active thermography with two different excitation sources were compared: optical and inductive excited thermography. Results of experiments obtained by these two techniques are showed and compared with each other. Opportunities of applying these methods in press shop are discussed.