Applied Mechanics and Materials Vols. 713-715

Abstract: In this paper, used hanging vibrating cone (HVC) concentrator to separate tailings overflow from shaping plant of China Tin Group under different conditions. Through analyzing the results of tests, founded that unavoidable ions in pulp have a great impact on fine cassiterite gravity separation.

Abstract: In this study, poly (vinylidene fluoride) (PVDF) hybrid membranes were prepared from polymeric blend of PVDF/tannic acid (TA)-Attapulgite (ATP)/PEG system via phase inversion induced by immersion precipitation in water coagulation bath. The membrane formation mechanism of PVDF/TA-ATP/PEG casting solutions in water bath thermodynamics at different temperatures and the process of membrane formation were investigated via cloud point determination and ultrasonic time-domain reflectometry (UTDR). The structures and properties of the membrane were characterized by scanning electron microscopy (SEM), and water permeation experiment, respectively. It was found that the rate of precipitation controlled by the Coagulation-Bath thermodynamics. With the coagulation temperature increasing, the gelation line was moved to non-solvent axis and the pure water flux were decreased.

Abstract: Nasogastric tubes are a widely used and vital piece of medical equipment for providing daily nutrition to patients, particularly in cases involving elderly patients or those with chronic diseases. However, current methods for stabilising nasogastric tubes are inadequate. Therefore, in this study, we employed a questionnaire survey to analyse the opinions and needs of medical staff. Subsequently, we incorporated these opinions with the innovation principles of the teoriya resheniya izobretatelskikh zadatch (meaning “the theory of inventive problem solving”) to develop a novel type of nasogastric tube stabiliser.

Abstract: The electronic structure and optical properties of wurtzite ZnO nanofilms with different thickness are investigated systematically by using the first-principles approach. The results indicate that the valence band properties of the ZnO nanofilms are mainly determined by the Zn: 3d state and O: 2p state. And its conduction band properties are determined by Zn: 4s state and Zn: 4p state. The band gap decreases with the thickness of nanofilms increasing in [0001] direction. It is also found that the interband transition absorption edge of ZnO nanofilms decreasing from 5.5 eV to 2.7 eV with the thickness of nanofilms increasing from single layer to five layers. The interband transition of reflection spectrum occurs mainly in the range of 10 eV to 18 eV, which is in line with the ionic bonding characteristic of wurtzite ZnO.

Abstract: 3D printing technology which is also named as fast prototypinghas shown excellent resultsto manufacture more complex and sophiscated products;hence is increasingly being developed and widely applied. Fused Deposition Modeling (FDM) is one of the most popular 3D printing techniques available today because it's simple and easy to make, these cheap printers nowadays are using this technology. Acrylonitrile Butadiene Styrene (ABS) is the material which is most commonly used among three kinds of common materials of FDM technology ABS, PLA, PVA. To design a patternfor using FDM technology using the printer UP2in particular, the exact calculations and the mechanical properties of the material ABS are required.The article focuses on testing the Izod impact strength.

Abstract: A fluid system consisting of polymer-based thickening agent (ACPAM) and a surfactant (Linear alkyl benzene sulfonate, LAS) is reported. The ACPAM polymer showed good thickening performance. At concentration 0.6 wt%, the viscosity of ACPAM solution reached 265 mPa∙s. ACPAM polymer solution was easily cross-linked by LAS at a wide pH range. The ACPAM gel system can be broken by ammonium persulfate under the temperature of 80~90°C. The residue content of the breaking fluid was low. Meanwhile, the ACPAM fluid system showed an excellent thermal stability & shearing resistance performance. It can be used in high temperature reservoir upto temperature 150°C.

Abstract: A steel channel with the size of 30×2×1.2 m was made to simulate the full surface fire of 50000 m³ methanol tank in coal-to-olefins industry. Some fire characteristic parameters of methanol were investigated, including flame spread rate, flame height, temperature distribution and radiation heat flux distribution. It is found that the flame spread rate of methanol is 1.98 m/s and the flame height could reach to 3.2 m. The temperature of methanol flame is first up and then down with the increase of height, while the highest temperature is 768 ^oC. It is also found that the radiation heat flux of methanol flame is in the changes between 4.4 kW/m² and 12.2 kW/m². The feature of methanol fire is different from the normal oil fire, which is worth for us to pay more attention.

Abstract: A modified model was presented for describing corrosion fatigue crack growth rate of aluminum alloy accurately. Considering the local damage around the crack tip is more reasonable for accelerating crack growth rate under corrosive environment, a damaged influence factors which characterize the damage degree of local damage near the crack tip has been introduced to revise the corrosion fatigue crack growth rate, and the experimental results are in good agreement with predictions of amendment fatigue crack growth rate model. The proposed model based on damaged influence factors is reasonable, and proposed a theoretical reference for aluminum alloy damage tolerance analysis.

Abstract: Copper testing strips are wrapped with three layers of Kraft paper and carried out aging experiment in corrosive sulfur contaminated insulating oil at 150 °C for 10 days. It is found that the copper sulfide is first formed on the surface of copper and tainted to the inner side of the insulation paper. Then the copper sulfide permeates through the paper and damages the dielectric property. In addition, flaking mechanism on the transformer failure is proposed. On the basis of this observation, different concentration of Irgamet 39 used as passivator is treated with the transformer oil containing corrosive sulfur, investigating the acidity, dielectric loss and corrosion to seek optimized condition. At last, long term stability of Irgamet 39 is studied by means of 208 transformers in service.

Abstract: The effects of multi-axial compression (MAC) on the microstructures and mechanical properties of pure magnesium were investigated. It has been shown that grain refinement and grain growth occurred simultaneously during the MAC process. After 5 MAC passes, the grain size is mainly distributed in the range of 5~25 μm. The hardness of the specimens increases with increasing the strain (MAC pass), with the increment at lower strain being more obvious than that at higher strain. Compression tests showed that the samples show significant difference in mechanical properties along different directions due to the texture development. With increasing the MAC pass, the texture has been weakened due to multi-axial deformation.