Advanced Materials Research Vols. 535-537

Abstract: The surface modification of chromium sesquioxide with lauric acid was investigated, and the optimum technical condition was obtained according to the activation indexes of products, i.e. 1% of modifier in weight，70°C in temperature and 40 minutes in time. Contact angle, FT-IR, XRD and particle size distribution were conducted on both unmodified and modified chromium sesquioxide. The results indicate that lauric acid molecules are adsorbed on the surface of chromium sesquioxide chemically and new bonds formed. The surface modification does not destroy the crystal structure of chromium sesquioxide even though the particle size of chromium sesquioxide is reduced from 4.01μm to 2.71μm. The contact angle of the modified chromium sesquioxide with water is 143 °, which indicates that the surface of the chromium sesquioxide changes from hydrophilic to hydrophobic.

Abstract: The functionalization of single-walled carbon nanotubes (SWCNTs) by noncovalent approach turned to be an effect strategy. Porphyrin and its derivatives are ideal materials for the decoration of SWCNTs. In this work, 5-(4-carboxypheny1)-10,15,20-triphenylporphyrin (H2CPTPP) was synthesized and covalently combined to the chitosan. The prepared chitosan/H2CPTPP composite was further conjugated with the oxidized SWCNTs to form chitosan/H2CPTPP/SWCNTs ternary composite. The results indicated that the carboxyl group of H2CPTPP was successfully introduced into the chitosan, which was confirmed by Fourier Transform infrared (FT/IR) spectroscopy, Raman shift and X-ray photoelectron spectroscopy (XPS). The solution of chitosan/ H2CPTPP/SWCNTs composite displays fluorescence quenching effect compared with that of chitosan/H2CPTPP composite at 615 nm and 654 nm upon excitation at 425nm.

Abstract: The advantages and disadvantages for several hybrid energy management strategies were analyzed in this paper. Power follower strategy served as the control strategy for some fuel cell electric vehicle. The control strategy was modeled and simulated in Advisor. The results indicate that the control strategy can manage the multiple energy sources well.

Abstract: It was detail studied that the preparation of new chelating materials derived from bagasse pith for adsorption of Cu2+ ion. The bagasse pith was modified by the ethylenediaminetetraacetic dianhydride (EDTAD) and the mechanism of sorption property for heavy metal ion was studied. The FTIR was used to characterize the esterified pith(EP). The results show that the optimal conditions are 24 h of reaction time and 1.5 g of EDTAD dosage and the maximum adsorption capacity for Cu2+ is 76.76mg/g. The peaks at 1743.62 cm−1, 1598.59 cm−1,1408.06 cm−1 in FTIR suggest carbonyl functions in the materials. The Langmuir model can describe the process of adsorbing Cu2+onto EP.

Abstract: Linen fibers oxidated by sodium periodate were anion-modified with sodium bisulfite, and treated linen fibers were dyed with cationic dyes. The thermodynamics principle of dyeing on modified linen fibers has been investigated by means of drawing adsorption isotherms,calculating dyeing saturation value and measuring dyeing levelness. The results indicate that adsorption isotherm of dyeing modified linen fibers with cationic dyes belongs to Langmuir adsorption isotherm,and the levelness of modified linen fabrics was better, the results indicate that the function of modification agent on linen fibers were more comprehensive and balanced.

Abstract: To prevent a long nozzle (LN) of non-preheating from rupture caused by thermal shock, heat insulation material (HIM) with a lower coefficient of thermal conductivity (CTC) was compounded in the inner hole (inner layer) or around the outer wall (outer layer), and the thermal stress was investigated. The two-dimension axially symmetric model of LN was proposed by simplifying the structure and boundary conditions. The influences of the HIM to the thermal stress of LN were analyzed by finite element method. The results show that the thermal stress suffered by LN can be drastically reduced by the inner layer, making the slow variation, but when its thickness increases from 2 mm to 3 mm, it almost has no influence on the thermal stress. The maximum thermal stress at the neck of LN reduces with the depression of the CTC at the inner layer thickness of 2 mm. The maximum thermal stress of LN can’t be reduced by outer layer, but the lasting time of higher stress can be shortened, and the thermal stress at the later period of steel-irrigating can be lowed. When the outer layer thickness is more than 2 mm, the increase of it has little influence on the thermal stress of LN, and the change of its CTC has little influence on the thermal stress either. The LN with tri-layer has lower thermal stress during all the period of steel-irrigating.

Abstract: The ligand, 5-Bromosalicyladehyde-nicotinoylhydrazone, and its complex of Mg (II) were synthesized. The formation of complexes was confirmed by elemental analyses, UV and infrared spectra. The luminescence properties of ligand and its Mg (II) complex were investigated in solid, respectively. The results show that the ligand exhibit green luminescence at 524 nm and the Mg (II) complex exhibit blue luminescence at 462 nm.

Abstract: The influences of BaF2 addition on phase composition, electrical property and energy storage density in strontium barium niobate based glass-ceramics prepared using melt-casting followed by controlled crystallization were investigated. The results indicate that adding 1wt% BaF2 improves the precipitation of Ba0.27Sr0.75Nb2O6 phase. However, the secondary phases, Ba3SrNb2O9 and BaBF5 are formed as the amount of BaF2 exceeds 3wt% when heated at 800°C/3h+900°C/3h in the glass-ceramics. The dielectric constant, microstructure, volume resistivity and breakdown strength are related to BaF2 content. The maximum breakdown strength (1450 kV/cm) and the energy storage density (5.1J/cm3) can be obtained in the glass-ceramic sample with 1wt% BaF2 addition, which would be suitable to be used as the dielectric materials for high energy storage capacitors.

Abstract: Ultraviolet aging of B.mori silk fabric was researched under different natural season weathering conditions. Exposed samples were removed periodically and characterized by several analytical techniques. During different natural season weathering, the results showed that the yellowness index of B.mori silk fabric surface appeared obviously rising in natural weathering especially in summer season, reaching 28.78% higher than 25.78% of yellowness index under spring season weathering; The peak intensity of amide I and amide II significantly declined, even disappeared; And the same time, the thermal behavior of B.mori silk changed similarly under different natural season weathering; In addition, breaking strength of B.mori silk fabric decreased approximately 86.27%, 95.11% under spring and summer season weathering, respectively. So, it was obviously shown that during the summer season weathering, the natural aging rate of B.mori silk was more quickly than spring season weathering, which was helpful to understand the aging behavior and measure the correlation aging effect between spring and summer season weathering condition.

Abstract: The crystallization kinetics of Li₂O-Al₂O₃-TiO₂-P₂O₅ (LATP) glass was studied by differential scanning calorimeter (DSC) and X-ray diffraction (XRD) techniques. The results showed that DSC curves of LATP glass have a single glass transition temperature followed by one crystallization peak for β = 5 K/min and two crystallization temperatures T_p1 and T_p2 for β ≥ 10 K/min. The activation energies of crystallization obtained from Kissinger model of the first exothermal peak and the second exothermal peak of LATP glass are 251 kJ/mol and 310 kJ/mol, respectively. The Avrami exponents of the both crystallization peaks are approximately 3, indicating that the three-dimensional crystalline growth during its amorphous to crystalline transformation. LiTi₂(PO₄)₃ and unknown crystalline phases firstly form when the mother glass was annealed at 973 K. With increasing of annealing temperature, AlPO₄ phase appears.