Advanced Materials Research Vols. 490-495

Abstract: The deformation of the prestress frame of open-die forging hydraulic press is studied in the paper. Firstly, the computing formula of true prestressing force of frame is deduced, and then the finite element model of prestress frame is established. With the model, the deformation of prestress frame is studied when the press works under different operating modes including upsetting, elongating and saddle forging and the effect of different operating modes on the deformation are revealed. The main achievements include: The true prestressing force of frame can be gained with nominal prestressing force, section area and working length of tension rods, section area and length of columns. Under prestress, the stress of the field of up beam and down beam acted by the axial force of tension rods and columns is bigger, that of the other field is very small. Under working loads, up beam and down beam tend to open out, tension rods and columns tend to bend in, and the bending effect cause the stress of inner field of tension rods bigger than that of outer field and the stress of inner field of columns smaller than that of outer field. The deformation of down beam under saddle forging is different with that under upsetting and elongating. The stress of center field of down beam under upsetting and elongating is higher and that of front and back field of down beam under upsetting is higher. The main achievements of the study are useful to design the prestress frame of open-die forging hydraulic press and the research method can be used to study the prestress frame of other equipments.

Abstract: An aluminum layer can be gotten on the worn-out work piece surface through ultrasonic-aided hot-dip and converted into alumina layer having wear-resistance performance though micro arc oxidation which can realize remanufacturing. The key technology of hot-dip aluminizing phase in above remanufacturing process is controlling the plating coat thickness. The influences of withdrawing speed, hot-dip temperature and hot-dip time on the plating coat thickness are analyzed in this paper.

Abstract: At present, doors and windows are still weak parts of building envelope structure in building energy-efficiency, and these energy-saving glasses applied currently do not have the intelligent adjustment function according to temperature, that is not conducive to building energy saving. In this paper, the key technologies to make energy saving glass with intelligent regulatory functions were studied: the preparation of nanopowder with regulatory insulation function and the dispersion of the nanopowder. The results show that: the long-term stable and uniform ATO dispersion can be batch produced by choosing a suitable dispersant, applying of rod mill combined with ultrasound process. Using industrial sulfuric acid oxygen vanadium, ammonium bicarbonate and sodium tungstate as raw material the nanometer VO2 synthesized can undergo phase change at room temperature. During the phase transition it has the obvious hot optical switching characteristics, and so it has the potential to achieve intelligent control functions of building glass.

Abstract: Hard and brittle materials such as silicon and ceramic materials are difficult to machining due to their brittle properties. By the ductile-mode machining, delicate features with high accuracy can be created on these materials by mechanical micro/nano machining. This paper introduced the experimental study on the ductile-mode milling of ceramics. First, the experimental background and plans have been introduced. Then, on the sub-micron milling center, experimental results show that ductile-mode machining can be achieved. Both machining parameters and machining conditions are very important in order to realize the ductile-mode machining

Abstract: Based on the treatment situation and the modification of effluent standard of printing and dyeing wastewater, a novel integrated and three-dimensional anoxic-aerobic process (A/O) is put forward. The experiment studies the startup of A/O process with simulated printing and dyeing wastewater. The results show that the removal efficiencies of CODcr, NH4+-N and chroma are 67.6%, 90.9% and 54.5% at the steady stage, respectively. The novel A/O process has perfect and steady performance for treatment of printing and dyeing wastewater.

Abstract: Chosed silicone resin with better waterproof and weatherability as raw material, epoxy resin and polyester as modifiers, developed a modified adhesive resin. By researching of the relation between content and property, the matching curing agent with polyfunctional groups was prepared, the modified resin was completely solidified. Properties test and analysis demonstated that the cured modified resin provided super resistance of salt fog and better surface abrasion resistance and perfectible high-temperature resistance

Abstract: Poly(N,N-diethylacrylamide) (PDEA) hydrogels possess a lower critical solution temperature (LCST) at around 31oC. When the external temperature is raised above the LCST, the hydrogels experience abrupt and drastic shrinkage. This unique property makes them very useful for biomedical applications such as on-off switches for modulated drug delivery and tissue engineering. In this study, itaconic acid (IA) was co-polymerized with N, N-diethylacrylamide (DEA) monomer to improve the LCST to the physiologic temperature about 37oC. These copolymer hydrogels were prepared by changing the initial DEA/IA molar ratio and total monomer concentration. The interior morphologies of hydrogels were characterized by scanning electron microscopy (SEM). In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) and LCST of the hydrogels increase with the increase of IA content in the feed. The deswelling dynamics behaviors of the different composition ratios of the P(DEA-co-IA) hydrogels on the different temperatures was investigated in detail.

Abstract: A new unsymmetrical photochromic diarylethene has been synthesized, namely {1-(2,5-dimethyl-3-thienyl),2-[2-methyl-5-(4-trifluoromethylphenyl)-3-thienyl]}perfluorocyclopentene. Its properties, including photochromic reactivity in solution and fluorescence property both in solution and in PMMA film were investigated. It underwent reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light. The isomeric compound functioned as a fluorescence switch by photoirradiation both in solution and in PMMA film. The fluorescence intensity also showed regular changes along with the change of concentration.

Abstract: A novel photochromic diarylethene with thiophene and benzene compound, 1-{[2-methyl-5-(1, 3-dioxolane)-3-thienyl]}-2-(2-cyanophenyl)perfluorocyclopentene(1a) has been synthesized. Its photochemical properties, including photochromic behavior and fluorescent features, have been investigated in detail. The compound showed good photochromism both in solution and in PMMA. The diarylethene exhibited a fluorescence switches along with the photochromism from open-ring isomers to closed-ring isomers. When irradiated by UV light, the photocyclization reaction was occurred and the emission intensity of the diarylethene decreased significantly, due to producing the non-fluorescence closed-ring isomers. The back irradiation by appropriate wavelength visible light regenerated its open-ring isomers and recovered the original emission intensity.

Abstract: A new unsymmetrical photochromic diarylethene bearing a benzothiophene aryl unit, 1-[2-methyl-5-(1,3-dithiolpentane)-3-thienyl]-2-[2-methyl-3-benzothiophenyl]perfluoroyclopentene has been synthesized, and its photochromic, fluorescence and optical recording strorage properties were investigated. The compound exhibited pronounced photochromic and clear fluorescence switching properties upon alternating irradiation with UV and visible light; the colorless open form with fluorescence character could be regenerated by irradiation with visible light. In terms of potential use for optical storage and readout, this compound displays fluorescence discrimination between its open and closed form. This fluorescence switching could be the basis of a remote control nondestructive readout method.