Advanced Materials Research Vols. 989-994

Abstract: The non-calcined phosphogypsum was modified and purified by quicklime, aged, treated by balling and cement coating, and then mixed with an appropriate amount of water, the cementitious material, gravel and so on. After using the vibration pressure molding process and the nature curing, the prepared high-strength and water-resistant phosphogypsum small hollow block can produce a softening coefficient of 0.82 and a compressive strength of 7.5 MPa, and the other properties meet the MU7.5 grade requirements of normal concrete small hollow block on the GB 8239-1997, which broadens the application range of phosphogypsum small hollow block, and may provide a new way to solve the comprehensive utilization of phosphogypsum.

Abstract: The aim of this research is to improve the electrical performance of the nanometer copper film by laser micro shock processing. The nanometer copper film was prepared by the magnetron sputtering. The mechanism of laser micro shock processing effect on electrical resistivity, hardness and elastic modulus was investigated. The results show that the electrical resistivity of copper film after laser micro shock reduced by 22.5 % on average. And, the hardness and the elastic modulus increased by 38.5 % and 45.2 % on average, respectively. According to our research, we conclude that, the existence of a large number of twin, twin boundary, fault and the grow up grain are the main factor of the improvement of the electrical performance; and the existence of twin, stress concentration holes and fault are the key to improve its mechanical properties.

Abstract: In order to improve the quality of sample and decrease the stress during process, it is important to study the residual stress distribution during direct laser metal deposition (LMDS) process. In this paper, according to the “element life and death” technique of finite element method ,with APDL, we simulated the effects of Laser power, scanning velocity, substrate preheat temperature and powder addition speed in top layer of samples residual stress distribution during whole LMDS process are studied. The residual stress distribution under different process parameters is researched in detail. Using the same process parameters, the simulation results show good agreement with the features of sample which fabricated by LMDS.

Abstract: Removal of benzene and effects of various parameters on the removal efficiency in the aqueous solution with plasma are studied. Results indicated that the degradation rate can be considerably raised by prolonging the discharge time, removal proceeded faster when the treatment was conducted in alkaline or acidic than in neutral media. Fe²⁺ shows an evident accelerated effect on the benzene elimination, and the presence of H₂O₂ benefited the degradation. It is demonstrated that the hydroxyl radicals were the most responsible oxidants in the benzene degradation. The major intermediate products resulted from the degradation were identified by an HPLC analysis and a degradation path way was proposed.

Abstract: Exhaustive Rhodamine B oxidation by means of contact glow discharge plasma in aqueous solution has been investigated. The rate of degradation in different conditions such as pH、H₂O₂、Fe²⁺、n-butanol, and other factors affecting was studied. The results showed that, there are faster removal rate when the solution was in a relatively higher acidity; H₂O₂ presence can improve the efficiency rate.Fe²⁺ can promote reaction. Radical scavenger, n-butanol, inhibits the Rhodamine B removal significantly. Some major intermediate products were detected by HPLC and GC-MS, respectively.

Abstract: ZnO: Al film was deposited on TPT substrate with SiO₂ buffer layer by RF magnetron sputtering. The obtained film had a hexagonal structure and highly (002) preferred orientation. The lattice constant distortion of the film with buffer layer was decreased and the compressive stress was 0.779GPa. The carrier concentratio reached to 3.15×10⁺²⁰/cm3. The resistivity of ZAO film with SiO₂ buffer layer was about 9.2×10^-3 Ω·cm and the average transmittance was over 72% in the range of 380~900nm.

Abstract: Fracture failure analysis on device clamp screws of one 110kV transmission line has been carried out based on results of macro-observation, pre-tightening test, mechanical property examination, chemical composition analysis, microstructure observation, SEM observation and EDAX analysis. It is concluded that the main reason of the screw fracture lies in misuse material and improper heat processing which led to material degradation. Suggestions are put forward finally.

Abstract: Based on the two-dimensional Hashin failure criteria and the introduction of material degradation damage factor, low-speed impact model of composite laminated plate was established by ABAQUS with fiber and matrix’s failure modes being taken into consideration. The mode is verified by referring to Karakuzu test. Next, it analyzes single ply thickness’ effect on laminated plate’s response and damaged under low-velocity impact. The result shows that with the thickness increasing, impact contact time and laminated plate impact point’s deflection displacement reduce, while the impact force and volatile shocks are more obvious.

Abstract: The process for ethylene glycol (EG) by catalytic hydrolysis of ethylene carbonate (EC) was studied. The influencing factors of the reaction products were studied which include the reaction temperature, the mole ratio of H₂O to EC, the mass fraction of the catalyst and the reaction time. The optimal conditions were identified as follows: the reaction temperature is 140-145°C, n (H₂O) :n (EC) = 2.0-2.5 : 1, the catalyst of Al₂O₃ is about 2.0wt%, the reaction time is about two hours. Under the above conditions, EC can be completely hydrolyzed and the selectivity of EG is above 98%.

Abstract: 3,4-Dihydropyrimidin-2(1H)-ones derivatives were synthesized in moderate to high yields in one-pot three component reaction from the corresponding aldehydes, 1,3-dicarbonyl compounds and urea, Coconut shell char sulfonic acid (CSCSA) used as a reusable, and efficient catalyst. Compared to the classical acid catalyst, This new protocol for the Biginelli reaction includes the following important features: excellent yields, non-toxic, inexpensive and easily available reagent.