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The elastic mechanical parameters of initial and pre-twisted copper wires were investigated with the aid of a self-developed micro-torsion tester. It was found that the apparent elastic shear modulus and the apparent Young tensile modulus of the copper wires decrease by 13.3 and 8.4% after pre-twist deformation, respectively. In addition, the indentation modulus also decreases as the deformation is increased. When the deformation is more than 30%, the indentation modulus of pre-twisted copper wires is smaller than that of initial copper wires. Microstructural analyses show that the elastic modulus decreases with the proportion of faults.

An optimized micro-torsion tester with high torque resolution, designed based on electromagnetism, is present. The torque capacity of this tester is 1.3 x 10(-3) N m with resolution of 4 x 10(-8) N m and the angle capacity is 115 deg with resolution of 0.016 deg. In order to verify the reliability of this tester, an improved torsion pendulum method is employed with the influences of damping, swing and axial force being carefully inspected. The same kind of copper wires with diameter of about 200 Am are tested using both this micro-torsion tester and the improved torsion pendulum. The two kinds of results of shear moduli are very close, which verifies the reliability of the self-developed micro-torsion tester. (C) 2017 Elsevier Ltd. All rights reserved.

To raise the recovery of oil during pyrolysis, reactions were performed on oily sludge using catalysts such as a molecular sieve and an Fe-containing molecular sieve catalyst in a tubular furnace reactor. The catalysts were prepared through hydrothermal method and characterized by various characterization methods. The results of the sample for the test have shown that more time could significantly increase the oil yield. The rate of oil recovery was increased with the increase of the catalytic in the initial phase and decreased at the back of the stage. In addition, higher temperature contributed to higher oil production, and at the same time the optimal ratio of molecular sieve catalytic to sludge was found to be 0.035. Research has revealed that the content of oil recovery rate could reach up to 85.52%. The effects of catalytic on the recovery improve rate of oil in oily sludge samples presented the following decreasing order of the molecular sieve and the Fe-containing molecular sieve.