Applied Mechanics and Materials Vols. 713-715

Abstract: This study uses a complete decomposition method to analyze the nature of the two factors that influence the changes in fertilizer use intensity by crops: fertilizer use efficiency effect and crop structure change effect. We find that: the reduction of fertilizer use efficiency was the main factor in the growth of fertilizer use intensity in the aggregate agricultural economy, while the structure change had a minor effect on lowering fertilizer use intensity; the crop structure change effect and fertilizer use efficiency effect both have positive effects on the growth of fertilizer use intensity in grain crops; the decline of fertilizer use intensity by economic crops was largely due to the crop structure change from high fertilizer use intensity type to low fertilizer use intensity type, while the increase of fertilizer use intensity by horticultural crops was mainly attributable to the structure change effect.

Abstract: Pure polystyrene (PS) was subjected to natural weathering in Qionghai (QH) and Ruoqiang (RQ) of China, representing hot and humid climate and xerothermic climate respectively. The degradation profile of pure PS was studied by Fourier Transform Infrared (FTIR) Spectroscopy, Differential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM), X-ray Photoelectron Spectroscopy (XPS) and Spectrophotometer. Artificial accelerated weathering tests protocol A and B were carried out to simulate hot and humid climate and xerothermic climate respectively. Results show that pure PS degrade slowly at the initial stage and then become faster. Color shift could be an appropriate indicator for evaluating simulated effect of artificial accelerated weathering and protocol A simulate hot and humid climate perfectly while protocol B turns out weak for xerothermic climate.

Abstract: The paper introduced the design procedure and design method of warm mixing regeneration mixture AC13. The water stability of warm mixing regeneration mixture was studied systematically with Evotherm warm mixing agent and self-prepared interface dispersant, the form change of old asphalt membrane and old aggregate in RAP was analyzed based on interface effect, and the optimum interface dispersant dosage was determined on this base. Results showed that: with the the interface dispersant dosage rising, significant changes of the TSR and splitting strength frozen-thawed before and after of warm mixing regeneration mixture occurred; when the interface dispersant dosage reached 2‰(based on RAP), both the TSR and splitting strength frozen-thawed before and after of warm mixing regeneration mixture were high,which verified the excellent water stability of warm mixing regeneration mixture; superfluous interface dispersant had negative effects on the water stability of warm mixing regeneration mixture.The exfoliation between old asphalt membrane and old aggregate and secondary coat were realized by interface effect.

Abstract: A waterborne anticorrosive coatings was prepared with homemade organic silicone 3-(trimethoxysilyl) propyl methacrylate modified epoxy acrylate emulsion as basic material, glass flake as anticorrosive filter and titanium dioxide as pigment and other additives. The anti-acid alkali salt, AC impedance, polarization curve tests were done to evaluate the coatings’ anticorrosion properties and to optimal its formula and process. The results showed that the best formula was: glass flake 35%, particle size 80 meshes, titanium dioxide as anticorrosive pigment 18% and the emulsion with epoxy at 45% content as base material. In this case, the coatings’ anti-acid, alkali and salt’s properties is good, the impedance values was up to eight orders of magnitude, the corrosion current was 9.59 × 10^-8A and every indicator met the requirements of the JB/T224-2007 "Building with Steel Structure Anticorrosion Coatings". The water-epoxy anti-corrosion coating has safe environmental protection, zero VOC, excellent anti-corrosion properties and other indexes meet national standards.

Abstract: Biotic ligand model (BLM) is a tool with the consideration of aquatic organism would have interaction with metals in different forms. Water chemical characteristics would also have some influence with bioavailability. In this study, BLM’s theoretical basis and realization process were discussed in detail, followed by the application status of the model. Finally, current challenges and future direction of BLM were pointed out. BLM assumes that the biological effect happens during the chemical equilibrium, which means that the model might only explain the acute toxicity results.

Abstract: For C-Si-Mn low carbon HSLA(High Strength Low Alloyed) steel, the influence of microstructure and properties were researched on the different annealing processes. The result showed that the microstructure at room temperature of the steel were polygonal ferrite, island martensite and punctate bainite. With the increase of the annealing temperature, the content of martensite and bainiteincreased and the content of ferrite decreased. Accordingly, tensile strengthincreased from 1069MPa to 1498MPa, and the elongation decreased from 13.8% to 5.1%. With the increase of the overaging temperature, tensile strength decreased from 1315MPa to 1152MPa, and the elongationincreased from8.5% to9.8%. Finally, the optimum annealing process obtained that the annealing temperature was 820°C for 80s, slow cooling to 680°C, water quenching to room temperature, the overaging temperature was 280°C for 300s and air cooling to room temperature. The material obtained higher tensile strength and better elongation.

Abstract: A kind of new plasticizer glycerol carbonate (GC) was synthesized. The poly (acrylonitrile-methyl methacrylate) (P(AN-MMA)) was prepared by bulk polymerization. During the polymerization, glycerol carbonate with 1M lithium perchlorate (LiClO₄) was added to (P(AN-MMA)) to form the gel electrolyte. The effect of the plasticizer on the conductivity of the copolymer electrolyte was studied. The ionic conductivity was found to be 3.3 × 10^-4 S·cm^-1 at room temperature via AC impedance measurement.

Abstract: The semisolid shear rheological properties of AZ91D alloy were tested. The effect of holding time on the rheological characteristics was investigated. The results show that: during the shear rheological test at 570 °C, a critical shear stress and a maximum shear stress are happened. And with the holding time increasing, solid fraction decreasing and solid particles distributing more uniformly, the rheological rate increases, but the critical shear stress and the maximum shear stress decrease.

Abstract: This article presents the dependence of porous silicon (PSi) morphology on preparation conditions and the coalition between morphology and optical properties. p-type (100) silicon wafers were etched in an electrolyte incorporating 1:1 (by volume) ethanol and aqueous solution of hydrofluoric acid (40 wt. %) at various etching current densities and times. Detailed information about evolution of PSi morphology with variation of preparation conditions was investigated by field emission scanning electron microscopy (FESEM) and atomic force microscope (AFM). The results have shown that the pore sizes of PSi are gradually increasing, and the thicknesses of PSi layer are increased with the speed of about 11-12 nm/s as the etching duration increased. Addition, the optimal photoluminescence of PSi is achieved in room temperature with the strongest photoluminescence spectra when the corrosion current density was 30 mA / cm² with 30 min etching time.

Abstract: Based on the background of continuously increasing requirements on the performance of recycle pavement materials, the effect of rejuvenator with different content (3%, 6%, 9% and 12%) and different type on recycled porous asphalt mixture was studied in this paper. The results shown that comparing with the ordinary rejuvenator which softening the aged binder effectively, the modified functional rejuvenator can also enhance the temperature stability and deformation resistance capacity of aged asphalt. In addition, the recycled porous asphalt mixture with modified functional rejuvenator has more excellent high temperature stability, water stability and fatigue performance. The result has great significance for the development of pavement recycling technology.