Advanced Materials Research Vol. 1035

Abstract: The soluble poly (ether ether ketone) (PEEK) containing trifluoromethyl group (FPEEK) was prepared by nucleophilic polycondensation reaction of 4, 4'-difluorobenzophenone and 4, 4′-(hexafluoroisopropylidene) diphenol in the presence of an excess of anhydrous K₂CO₃ with tetramethylene sulfone as the solvent. The structure and thermal stability of FPEEK were studied by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, X-ray diffractometer and thermogravimetric analyzer. The solubility of FPEEK was also investigated using different organic solvents. Then the solution of FPEEK in N, N-dimethylformamide (DMF) was applied to prepare insulating coating. The mechanical properties of the coating were tested. The results show that FPEEK is soluble in common organic solvents such as chloroform, tetrahydrofuran and DMF. FPEEK shows high thermal stability with the initial degradation temperature of 536 °C in nitrogen. The insulating coatings of FPEEK exhibit the good adhesion, flexibility and impact resistance.

Abstract: One-dimensional dielectric photonic crystals (PCs) with complex substitutional defect layers, consisting of superconducting (SC) and dielectric sublayers are theoretically studied. The influence of the incidence angle on the photonic gap spectra is theoretically analyzed. The pronounced difference in the transmittivity spectra of the PCs with right-handed (RH) and left-handed (LH) positions of the superconducting defect sublayer with respect to the dielectric defect sublayer is demonstrated. It is observed that, for the case of RH SC defect sublayer, the position of the defect mode and the transmittivity at the defect mode frequency strongly depend on the thickness of the superconducting sublayer as well as on the temperature. But the defect modes of the PCs with LH SC defect sublayer are nearly invariant upon the change of the thickness of the superconducting sublayer and the temperature.

Abstract: For understanding the dynamic behavior of open and closed foam subject to a shock wave, this paper through experiments, to gain a deeper understanding of the incidence, reflection and transmission of a shock wave when it interacted with cellular foam. Moreover, by analyzing the loss of the peak overpressure and positive impulse, we were able to respectively know the positive impulse of the incidence, reflection and transmission shock wave. The experimental results indicated that the attenuation capability for foam to the shock wave was caused by the internal friction and deformation of solid phase, which would absorb the energy of the shock wave. From the results we gain an understanding that the mechanical phenomenon of open foam to shock wave are not fully consistent with those of closed foam , while the attenuation of open foam to shock wave is more effective than that of closed foam.

Abstract: The photoaging of coating based on toluene diisocyanate (TDI) and N75 was investigated though artificial light exposure. The properties of studied polyurethane coatings, such as film gloss loss and discoloration were examined at some aging interval. In addition, scanning electronic microscopy (SEM) and Fourier transform infra-red spectroscopy (FTIR) were used to measure the morphology and chemical change of coatings before and after exposed under UV light. It was found that the addition of N75 had a significant effect on the discoloration of polyurethane coating. Furthermore, SEM images showed that greater degradation occurred in the coating without N75. These findings were also supported by the results obtained from FTIR analysis and gloss loss. The above results suggested that a mixed curing agent system with a mass ratio of TDI to N75 between 5:5 and 3:7 be a possible substitute of pure N75 for weather resistance PU coatings.

Abstract: A coating methods and the structure of Low-E glass are described in this paper, and the optical and thermal properties of the samples are analyzed as well. The results show that the Low-E glass has a high transmittance in visible region and with a higher reflectance in middle-infrared band and far-infrared band. It can effectively prevent the heat through the glass. Therefore, Low-E glass can save energy by letting enough sunlight into the room and by impeding the heat through the glass effectively.

Abstract: The chiral monomer,N-acryloyl-L alanine, was synthesized by condensation reaction between acryloyl chloride and L-alanine using ethyl acetate and water as two-phase solvents, tetrabutyl ammonium bromide as phase transfer catalyst and ethyl acetate as the extraction solvent.And then, poly (N-acryloyl-L-alanine) was successfully prepared by free radical polymerization of above synthesized monomer using 2,2'-Azobis (2-methylpropionitrile) AIBN as initiator in ionic liquids. Their structures were characterized by ¹HNMR and IR. Optically activities were tested with Rotary Spectrometer. Melting point and glass transition temperature were tested with DSC. The molecular weight of the polymer was characterized with GPC.

Abstract: Optical Emission Spectrum (OES) was utilized to monitor the deposition procedure of copper film byradio frequency (RF) magnetron sputtering.The plasma was found to contain Ar, Ar+, Cu and Cu+ when Argon was the working gas. The OES intensity of each composition increased with the increase of the input power of sputtering. Furthermore, intensity of Cu was higher than that ofAr, Ar+ and Cu+. The mechanical property of as-deposited Cu film was measured by scratch test method. It was found that with the increase of the input power, the adhesion strength possessed the maximum value while the square resistance decreased and surface roughness obviously. Theory calculation shows these properties were connected to kinetic energy of atoms in the plasma.

Abstract: The adsorption properties of water molecules on oligo and polysaccharides are attributed to the OH groups of the glucose rings in the molecules. The water molecules are adsorbed onto OH groups by hydrogen bond formation. Near infrared spectroscopic and gravimetric techniques were used in analysing the adsorption characteristics of malto-oligosaccharides and some polysaccharides. Near infrared spectra of the dry oligo and polysaccharides were acquired during the adsorption of water molecules at a relative humidity of 50-55%. The amounts of water adsorbed by the samples were also recorded by an analytical balance. Second derivative techniques were used in decomposing the OH combination frequencies of the adsorbed water molecules in the region 5300-5000 cm ^-1.The results indicate that the water molecules are adsorbed on to C2 and C3-OH groups at a higher rate compared to the adsorption onto C1-OH groups in the molecules. Adsorption also takes place onto the ethereal oxygen atoms in the glucose rings in malto-oligosaccarides. The gravimetric results show that the adsorption of water molecules increases with the number of glucose units in the malto-oligosaccharides except maltotriose which has the highest adsorption over a period of 75 minutes. Furthermore, the adsorption characteristics of amylose and amylopectin are similar.

Abstract: Lateral flow test kit has become a popular device for immunoassay of biologically important molecules. Colloidal gold strip has been commercially available for point-of-care clinical testing at hospital or simply at home for self-testing. A method for reading the reaction results of colloidal gold strip assays is proposed. The RGB (red-green-blue) image of a reacted strip is captured by smartphone under natural-light illumination. The two-dimensional grayscale image of each color channel is transformed into nine images by spatially shifting the image in eight adjacent directions. After all three color channel images are transformed, an array including twenty-seven images is constructed. Multiway principle component analysis is then used to the array, extracting texture information of the original image. When the extracted texture is added back to the original image, color of control line and test line regions can be effectively enhanced for reading by naked eyes.

Abstract: Hollow nickel ferrite microspheres with a diameter of about 1.5 to 2.5 μm were synthesized using an emulsion-based solvothermal method in combination with calcination at 550°C. The structures and morphologies of the nickel ferrite microspheres were characterized using an X-ray diffractometer, a transmission electron microscopy and a field emission scanning electron microscopy. Magnetization measurement was carried out using a vibrating sample magnetometer at room temperature. The saturation magnetization and coercivity of nickel ferrite microspheres could reach 19.41 emu/g and 202.28 Oe, respectively. Hollow nickel ferrite microspheres might be used as catalysts, magnetic materials and microwave absorbers.