Advanced Materials Research Vols. 415-417

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Abstract: The title compound has been prepared from the reaction of fluorescein and 1-bromobutane in the presence of potassium carbonate. Its crystal and molecular structure is determined by single crystal X-ray diffraction. Its crystal is monoclinic space group P2(1)/n with lattice parameters: a = 8.0460(19) Å, b = 13.198(3) Å, c = 22.208(5) Å, α = 90.00º, β = 94.140(3)º, γ = 90.00º, V= 2352.1(9)Å3, Density (calculated) 1.228 mg /m3, μ(mm-1) = 0.08, absorption coefficient = 0.082m−1, F(000) 1034, Z = 4. In the crystal structure, intermolecular O-H hydrogen bands are responsible for the formation of a 3-dimensional net-work. The UV-vis absorption and fluorescence spectra of both dibutyl ester-ether fluorescein was studied.
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Abstract: A kind of the ionic bolaform surfactant was synthesized in four steps, with 4-nitrotoluene as raw materials. Firstly, bis-(2-methyl-4-nitrophenyl)-methane (BMNM) was synthesized using paraformaldehyde as a coupling agent; then, bis-(2-methyl-4-aminophenyl) methane BMAM) was obtained through a reduction reaction of BMNM; in the following step, bis-(2-methyl-4-p-hydroxy- azophenyl)methane was prepared through diazotization-coupling reaction; at last, Bolaform surfactant was obtained through a addition reaction of butane sultone and bis-(2-methyl-4-p- hydroxy-azophenyl)methane. The products were characterized by IR and 1HNMR. The surface tension and UV-Vis absorption and fluorescence spectra of aqueous solution of this Bolaform surfactant were tested. The cis/trans photoisomerization of Bolaform surfactants were studied in DMSO solution at 365nm irradiation, which indicate this Bolaform surfactantis photosentive and easily to control surface activity by photoisomerization.
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Abstract: IVB-group transition-metal nitrides are hot research materials due to their high hardness, good thermal stability, and excellent mechanical properties. In this paper, we studied the lattice parameters, elastic properties, electronic structures, and hardness of the face centered cubic TiN, ZrN, and HfN. The research shows that all the three types have excellent elastic properties. According to the result, elastic properties of HfN are the best of the three, as its bulk modulus and shear modulus are 278GPa and 240GPa respectively. With the calculation of electronic density of states, we find that all the three types are metallic. The wide pseudogap in DOS and the large overlap population indicate the strong Ti-N, Zr-N, and Hf-N bonds. The lower value of the density of states on the Fermi level shows that crystal structure of HfN is more stable. That is why the elastic properties of HfN are better than the others, mainly. The calculated hardness of TiN is 23.6GPa, which is the highest.
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Abstract: Waste plastics are environment problems needed to be solved. Amount of studies have showed that waste plastics can be used as a part of construction materials. However, the hydrophobic property of organic polymers is a fatal issue should be solved. In this study, acrylamide monomer (AAm) was grafted onto PE surface by using benzophenone (BP) as a photoinitiator. Contact angle, surface functional groups, and surface morphology of PE films were characterized for original and AAM-grafting PE films. The interfacial zone of PE and CSH was observed with SEM. Experimental results showed that AAm could be successfully grafted onto PE surface. The hydrohilicity of PE was enhanced by AAm grafting.
1457
Abstract: In recent years, epoxy asphalt is used widely in the waterproof cohesive layer material of steel deck pavement. This material has obvious advantages in cohesion, deformation capacity and hot stability. This paper analyses the effects of water and temperature on the performances of epoxy asphalt waterproof cohesive layer by indoor shearing and pulling tests. It has important theoretical significance and practical value for the development and application of epoxy asphalt waterproof cohesive layer material.
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Abstract: The mineral structure and hydration activity changes of the Jiyuan gangue calcined at different temperatures were studied in the paper. Differential scanning calorimeter (DSC), X-ray diffraction (XRD) testing, strength testing of cement and Microhardness analysis methods were used to study the thermal activation of coal gangue mineral composition, and macroscopic characterization of the activity of heat-activated coal gangue. The results showed that after heat activation, the destruction of the gangue can be effective in the silicon-oxygen bond, aluminum-oxygen bond, forming amorphous material, and thereby enhanced the activity of coal gangue. Best thermal activation process conditions of Jiyuan gangue is calcined at 800°C for 2h. Adding 40% of the heat-activated coal gangue Activated at this condition to cement, the compressive strength than the same dosage as is the compressive strength of coal gangue increased 106%.
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Abstract: The aim of this study is to analyse the adhesion mechanism of prepainted steel sheet at UV ageing to simulate nature environment by means of T-bend, FTIR, SEM, EIS. After 2000 hours of ageing in the UV chamber we observed the adhesion decline of prepainted steel sheet by the T-bend test. Taking into account the characteristic peak position and intensity of FTIR spectroscopy was Hardly any change during the ageing period, there is no chemistry reaction on the organic coatings. However, After 2000 hours ageing the electrochemical impedance spectroscopy (EIS) of the prepainted steel sheet showed lower impedance. SEM result indicated that larger defects were found on the coating surface, which it is easy that the outside corrosive substances to meet metal substrate. In this way, the corrosive medium accelerated corrosion electrochemical reaction on the metal. growing corrosion products diffused between the metal substrate and the organic coating to destroy their binding. At last, the increscent corrosive area on metal interface caused the adhesion decline.
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Abstract: Abstract. Based on the electro-thermal property of carbon fiber-reinforced concrete, two groups of carbon fiber with equal quality dispersed in cement mortar deferring to layered and gradient distribution separately. The heat change of electro-thermal layer (with carbon fiber) and non- electro-thermal layer (without carbon fiber) of the two kinds of specimen was contrasted, and the corresponding thermal stress value among each layer was calculated theoretically. The results indicate that comparing with the carbon fiber layered distribution, carbon fiber gradient distribution decreases the thermal stress maximum of neighboring layers from 15.42MPa to 5.21MPa. The decrease of heating stress increases heat stability, by which can enhance cement mortar service life.
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Abstract: The case studies on the damaged pile foundation caused by lateral flow due to soil liquefaction during the big earthquake were discussed. The distributed load method was utilized to calculate the stress and displacement. The effect of the lateral flow to pile foundation in liquefiable soil also is simulated. Through compared the analysis result to the site dig-investigate report, the mechanism of the damaged pile modes were conjectured very well. the calculated stress and deformation of piles indicated good agreement with the actually observed one. The practicability and availability of the distributed load method was substantiated.
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Abstract: The second phase nucleation and precipitation around the edge dislocation are studied using phase-field method. A new free energy function is established. The simulation results are in good agreement with that of theory of dislocation and theory of non-uniform nucleation.
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