Abstract: Polyurethane-acrylic composite emulsion was synthesized by swelling polymerization with aqueous polyurethane dispersion as seed, and acrylic as monomers. The obtained polyurethane-acrylic (PUA) composite emulsion were characterized by means of IR spectra, and the results showed that the obtained emulsion was hybrid emulsion of polyurethane and acrylic, which had smaller particle size and higher viscosity and was more suitable for the preparation of ink. The obtained water-based PUA emulsion and alkyd resins were used as ink binder. The obtained water-based ink had good water resistance, color density, gloss and friction fastness.
Abstract: Cutting force experiments in turning aluminum-silicon alloy were carried out with cement carbide tool YG8. Experimental formulae of cutting force, back force and feed force were determined based on multi-variable linear regression analysis, and they were verified by analysis of variance, the results showed that the regressed models could be used to predict cutting force under certain conditions.
Abstract: Based on the “ex-situ” toughening concept, thermoplastic nylon (PA) nonwoven fabric with high porosity was chosen as the toughening layer, and the interlaminar toughened composites were fabricated via RTM process. Compression strength after impact (CAI) properties were investigated as well as the toughening mechanism. The results indicated that there is no bicontinuous phase structures formed by reaction-induced phase decomposition and inversion. The PA nonwoven fabrics still kept the original structure in composites interlaminar, and formed a macroscopical bicontinuous structure with the matrix resin, which also showed remarkable toughening effect. The CAI value increased from 212MPa to 281MPa.
Abstract: In present article, the low intensity magnetic separation process was studied for the low-grade niobium minerals by microwave magnetic roasting. The influence of magnetic density, particle size of grinding and dispersant addition on the magnetic separation effect of sinter ore with the best magnetisability was investigated emphatically. The results show that the iron recovery was decreased and the iron grade increased gradually with decreasing the magnetic density and particle size of grinding. The magnetic separation result of sinter ore was optimal under the magnetic density of 80KA / m and the grinding grain-size of 33 μm. Fine grinding can effectively make Fe separated from Nb, especially when the dispersant(industrial alcohol) was used in the process of magnetic separation , resulting in the improvement of the grade of iron from 57.2% to 60.5% and enrichment of Nb in the tailing ore(the grade of Nb was 5.01%). After the acid pickling of tailing ore containing Nb, the grade of Nb in the extract was improved to 12.36%, which was enriched four times more than that of low-grade niobium ore before microwave magnetic roasting.
Abstract: A ferro-hydrodynamic ( FHD ) model, based on modified Bernoulli theory, to estimate the average ferro-flow velocity is developed in this study. In which, the effective viscosity, strongly dependent on the magnetic intensity and volumetric concentration of ferro-particle, is considered. Referred to the Langevin function, the induced magnetic pressure together with hydraulic head as well as frictional head successfully formulates the modified ferro-Bernoulli model .To correct the analytic results, a self-designed experimental mechanism, equipped with light gate and current-carry solenoid, is set up as well ,which is used to measure the average velocity of piping flow via the duration recorded for ferro-fluid passing through both light gates While compared with experimental results, a good agreement of analytic solutions will be delivered within the working magnetic intensity ,0~36 mT, and the flow velocity is found to be significantly reduced during initial magnetization 0~12 mT as the working condition, subjected to ferro-concentration 0.04~0.4 at temperature 25 oc~45 oc, is specified in this study.
Abstract: The design and construction characteristics of cast-in-situ concrete hollow floor are introduced and the difficulties of the construction system are discussed in this paper. Based on the analysis of the engineering, the construction technology is introduced and its application is evaluated.
Abstract: As a conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. We investigate the preparation, configuration and capability of the unsaturated resin/ graphite nanosheets conductive composites and the oriented theory of the graphite nanosheets induced in the electric field. The measures and observation of scanning electron microscopy(SEM), X-ray diffraction(XRD), electric current have shown that the graphite nanosheets are oriented by electric field which were randomly dispersed in the polymer matrix at the beginning, and then oriented with their flakes along the electric field in the polyester resin.
Abstract: This paper studied on the application mechanics and characteristics of the polyurethane-acrylate composite emulsion applying to the pre-coated adhesive film of paper and plastic laminating. The formula design and synthesis method of the polyurethane-acrylate composite emulsion was researched, and the physical properties of the copolymer emulsion was tested by infrared spectroscopy (IR), particle size analysis, gel permeation chromatography (GPC). According to mix the waterborne polyurethane acrylate emulsion to the waterborne rosin emulsion, the hot melt pre-coated adhesive was obtained. The experimental results based on the physical properties and image analysis of the pre-coated adhesive film of paper and plastic laminating showed that: the adhesive film coated by this hot melt adhesive had a high gloss and adhesive force, it improved the application performance of the pre-coated adhesive film of paper and plastic laminating in the printing and packaging industry.
Abstract: As-received plastic PAEK membranes were inserted into each layer of T800H/5228A prepreg for improving composite tougheness, generally characterized by compression after impact.The microstructure revealed that a reaction-induced phase decomposition and inversion happened in the interlaminar region, as what does in PAEK/epoxy compound beyond 35phr content.Compression after impact and GIC,were doubled without biggish loss of other main in-plane mechanical properties.