Applied Mechanics and Materials Vols. 713-715

Abstract: This study was conducted to screen the acid and bile resistant Bifidobacterium bifidum strains through repeatedly domesticating. In acid-resistant domestications, low pH tolerance Bifidobacterium bifidum single colonies were obtained by gradually lowering the pH of the liquid TPY basic medium. And then the achieved acid-resistant strains were domesticated through gradually increasing the concentration of bile salt in milk medium. Each time acid and bile resistant single colony was selected after the domestication. The results showed the domesticated Bifidobacterium bifidum strain presents high acid and bile resistant capabilities; morphologic observation and sugar ferment experiments results indicate the domesticated stains did not have any unique mutations. This research showed practical application potential development viable maintenance of Bifidobacterium bifidum products.

Abstract: Anilox is the most important part in flexography, we simplified the structure of anilox roller into an axisymmetric trapezoidal groove, while established a numerical simulation of the ink transfer process by using the finite element method. We had done research on ink transfer characteristics in the flexographic printing process. The ink transfer ratio decreased when the upper plate contact angle increased, while increased when the dovetail groove contact angle increased; the aspect ratio also have impacts on the ink transfer.

Abstract: Welding temperature is the main factor that influences welding quality in high frequency induction welding process of composite aluminum alloy thin-walled tube. The finite element analysis software ANSYS is used to simulate temperature field. One complete penetration of thin-walled tube and boundary conditions of thermal calculation are taken into account. Then a linear thermal model is used to load and calculate to draw temperature distribution and thermal cycle curves of welding process. Research results provide corresponding theoretical basis for further analysis of welding stress and strain.

Abstract: A simple and cost-effective low temperature (600 oC) solid phase method was proposed for the synthesis of CdTiO₃ submicron particles, using Cd (OH)₂ and P25 TiO₂ as the starting materials. The composition and structure of the as-synthesized CdTiO₃ submicron particles were characterized by X-ray diffraction and transmission electron microscopy. Besides, the optical properties of the as-synthesized CdTiO₃ submicron particles were characterized by UV-vis diffuse reflection spectrum and photoluminescence spectrum.

Abstract: The Cadmium^II Isophthalicacid Benzimidazole complex [Cd₂(C₈H₄O₄)₂ (C₇H₆N₂)₄(H₂O)₃], Triqua-bis (isophthalicacidato-O,O')-tetra (benzimidazole) bis (Cadmium^II),the Cd^II atom is coordinated by two isophthalicacid anions and two benzimidazole and one water molecule in a distorted octahedral configuration with six-coordinations geometry. And one isophthalicacid ligand chelates to the Cd^II atom through its one carboxylic O atoms, but the other isophthalicacid ligand chelates to the Cd^II atom through its two carboxylic O atoms. The same as another Cd^II atom. So we get a Binuclear Cd^II metal complexe. The fact clearly suggests not so much significant contribution from the electrostatic interaction in the Cd-O bonding in bidentate Binuclear Cd^II metal complexes as we gotten in mononuclear Mn^II metal complexes. Adjacent complex link to each other via hydrogen bonds forming the three-dimensional supramolecular structure.

Abstract: The semi-solid rheoforming process of AZ91D alloy with 9 % plastic deformation was investigated. The effect of holding time on the rheoforming formability of AZ91D alloy was analyzed. The relationship between holding time and microstructure, mechanical property was also researched. The results show that with increasing of holding time from 0 to 60 min at 575 °C, the filling distance increases firstly and then decreases, the solid fraction decreases firstly and then increases, the tensile strength and elongation are also increase firstly and then decrease. However, the increasing of holding time would lead to shape factor decreasing but particle coarsening. When holding time is 30 min, the solid fraction is lowest and the filling distance increases greatly. Compared to the conventional casting sample, the tensile strength and elongation of the rheoforming parts increase 43.9 % and 187.5 %, respectively.

Abstract: Microarc oxidation (MAO) surface modification course on high-purity Mg at constant DC and the resultant ceramic coatings were investigated. MAO was the course in which the pre-existing film/coating was modified or substituted and strengthened repeatedly. SEM disclosed the inhomogeneous formation rate of ceramic coating in different micro-regions at anode surface during MAO. Three-stage behavior of MAO including pre-microarc discharge stage, transitional stage and then further modifying stage was put forward. The latter two stages proceeded under continuous discharge conditions, accompanied by intensive evolution of gas. EDS analyses indicated that the resultants of MAO consisted mainly of Mg, O and Si elements. XRD analyses revealed the dependence of phase composition on treatment time and coating layer depth.

Abstract: Poly (vinylidene fluoride)/attapulgite (PVDF/ATP) hybrid membrane was prepared for removal of Cr (VI) ions from wastewater with PVDF as matrix and ATP as adsorbent which was functionalized by cetyl trimethyl ammonium bromide (CTAB) and then modified by tannins (TA). The adsorption kinetics and equilibrium isotherms of the hybrid membranes were particular concerned. The results indicated that the PVDF/ATP membrane displayed a good adsorption capacity for Cr (VI) ions, the adsorption equilibrium could be established within 5 hours and the maximum adsorption capacity was 21.4 mg/g. The adsorption kinetics fit well with Lagergren second-order equation and the adsorption isotherms can be well described by Langmuir and Freundlich models.

Abstract: With five strains of plant pathogenic fungus Exserohilum turcicum Pass. as test material, carbendazim and chlorothalonil as bacteriostats for compare, the bacteriostasis of silver nanoparticles on the growth of mycelium, the spore germination, as well as the inhibition zone and conductivity was studied. The results show: the bacteriostatic effect of silver nanoparticles is all significantly better than blank control, indicating that silver nanoparticles has better bacteriostatic effect on E. turcicum Pass. And there is an interspecific difference for silver nanoparticles’s bacteriostatic effect on the five strains, the bacteriostatic effect of the strain 85-3 is better than 85-1, 85-2, 85-4 and H15. In the comparison among silver nanoparticles, carbendazim and chlorothalonil, the latter two have no significant difference in their bacteriostatic effect, but they are better than silver nanoparticles. Silver nanoparticles’s bacteriostatic effect is achieved by changing the permeability of the cytomembrane.

Abstract: The laser alloy cladding technology is used to treat the surface of 40Cr, and the two alloy powders are used separately. The process parameters are different, such as laser power, feed rate and scanning speed etc. The microstructure and hardness of cladding layers are analyzed by using scanning electron microscope and hardness tester. Generally, the surface quality is improved apparently. Under the similar laser power and powder quantity, the thickness of Ni60 cladding layer is much larger than Fe60. The hardness of Ni60 layer and Fe60 layer are all higher than substrate. There are more cracks in Ni60 layer than in Fe60 layer. The parameters of sample No.1 is optimal.