Materials Science Forum Vols. 663-665

Abstract: Based Plank’s radiation law, thermal radiation intensity depends on radiation wavelength and material temperature. As the increase of material temperature, thermal radiation wavelength will decrease from infrared waves, next to visible light, last to ultraviolet light. In order to research the spectral distribution of molten pool at different temperature in laser fabricating, thermal radiation of standard BF1400 blackbody furnace in National Institute of Metrology of China was measured by CCD technique. Its high-temperature cavity radiators glow which was dim red at 600 oC, bright red at 800 oC, yellowish red at 1000 oC, bright yellow at 1200 oC. The thermal radiation in visible spectrum range could be acquired by CCD, which was translated into grey data of red, green and blue radiation intensity. It was shown that grey gain at red, green and blue wavelength was different greatly as increase of blackbody temperature, extremely large at red wavelength, little at blue and green wavelength. When thermal radiation of molten metal pool at red, green and blue wavelength in laser fabricating was acquired to analyze the relation between spectrum and temperature, the green and blue wavelength will be good choose for its colorimetry temperature analysis.

Abstract: Antimony bismuth alloy films were deposited on Si and K9 glass substrates by magnetron-control sputtering method. The structure of the film was studied with x-ray diffraction (XRD). The thermal property of the film was researched by differential scanning calorimetry (DSC). The optical constants of the films including refractive index (n) and extinction coefficients (k) are measured by ellipsometry, and the dielectric constants (=r+ii), absorption coefficients  were also calculated.

Abstract: Carbazole derivative is one sort of important nonlinear optical materials. In this work, new symmetric-type D-π-D carbazole derivatives, 3, 6 - di- substituted carbazole chromophores with two styryl bridges of the two-dimensional conjugated D-π-D system were synthesized via Witting reaction and characterized by IR, NMR and MS. The third-order nonlinear optical properties of the material were investigated using single-beam Z-scan technique with Sapphire femtosecond laser pulses at 800nm, repetition rate of 1 KHz and pulse width of 140fs. The results of Z-scan with and without an aperture showed that larger third-order nonlinear optical polarizabilities γ can be readily obtained in such carbazole chromophores because of the incorporation with two styryl bridges, increasing of conformational planarity and molecular conjugation length.

Abstract: The polymerizable monomer encapsulating CdTe quantum dot was synthesized by the electrostatic reaction. Then CdTe/PMMA was successfully obtained via free radical bulk copolymerization with the mixture of the polymerizable monomer and methyl methacrylate, which emit green light under visible light. The structure and optical properties of CdTe/PMMA were investigated by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), Uv-vis absorption spectrum, and fluorescence spectrum, respectively. The results indicated that the CdTe/PMMA emit green light under ultraviolet and visible region (380-500nm). When the polymerizable monomer encapsulating CdTe quantum dot was 1.2%, the fluorescence quantum yield of CdTe/PMMA was 7.1%.

Abstract: A simple combustion process has been proposed to systematically synthesize Ca3((P, V)O4)2: Eu3+. All the Ca3((P, V)O4)2: Eu3+ products were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spect rophotometer. The results indicate that Ca3((P, V)O4)2: Eu3+ phosphor particles is special morphology with quadrate of length 2.5 μm and breadth 1 μm. From the photoluminescence spectra for Ca3((P, V)O4)2: Eu3+, the remarkable emission transition 5D0 – 7F0 are assigned to Eu3+ ions substituted for Ca2+, and the most intense emission transition 5D0 – 7F2 indicates at noncenter symmetrical environment for Eu3+ ions. It was observed that the spectral features possess sharp and bright emission for a red emitting nanophosphors potential applications.

Abstract: In this paper, we report a simple two-step approach (microwave-calcinating) to prepare skin-colored N-doped ZnO nanocrystals. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS) and UV-visible absorption were used to characterize the as-synthesized products. The FESEM results reveal the products mainly take on the morphology of porous flake constructed by 20 nm nanoparticles. UV-Vis spectrum shows a strong absorption peak located at 384nm.

Abstract: According to the optical-electric properties of liquid crystal, an eye controlled focus (ECF) anti-glare imaging detector is designed. Considering the existed concept of point metering controlled by the eye, a new concept of photometry, point-by-point single-pixel metering controlled by the eye, is brought forward. The method of ECF in the detector is researched. Firstly the pupil’s image is attained, and then the detector focuses with the focused function. Besides, a distinct image and a vague one are processed. The focused function values of the two images are 8.5057×103 and 7.2381×103 respectively.

Abstract: A stable and high lubricant ultrathin film was fabricated by self-assembled procedure at room temperature. Thickness of the films was regularly increased with the layer-by-layer self-assembly process in which poly (acrylic acid)-ferric hydroxide (PAA-Fe(OH)3) sol as anion polyelectrolyte and photosensitive diazoresin (DR) as cationic polyelectrolyte. And the process which based on electrostatic attraction was verified by UV-vis measurement. Furthermore, the ionic bonds in the films converted to covalent bonds under UV irradiation. Finally, the surface morphology and microtribology of the films were investigated by atomic force microscopy (AFM) and friction force microscopy (FFM). The results indicate that the films are flat and uniform through the self-assembly technique and the surface friction coefficients maintain at a rather low value.

Abstract: Color conversion method has been used to fabricate chromatic-stability white organic light-emitting diodes (OLEDs). Experimental results found little CIE coordinate migration while changing operation voltage from 5 V to 12 V. A simple thin-film encapsulation (TFE) structure has been developed through vacuum thermal deposition in combination with plasma enhanced chemical vapor deposition. The luminance of the encapsulated white OLED remain unchanged during the test time. The novel approach is being expected to lower the cost and achieve high-performance TFE.

Abstract: Tungsten oxide (WO3) film material is applied extensively because of its electrochromic property, gasochromic property, photochromic property, electrochemistry, etc. Based on the preliminary study on the preparation and hydrogen sensing properties of platinum-doped WO3 films, we studied the optical properties of hydrogen sensitive WO3 films for surface plasmon resonance (SPR) optic-fiber micro-sensor. In this work, firstly, the structure of SPR optic-fiber hydrogen micro-sensor was discussed. Secondly, we studied the transmissivity of the platinum-doped WO3 films. Thirdly, the reflection index of the films in different environments was discussed. This work can provide theory support for the design of SPR optic-fiber micro-sensor.