Advanced Materials Research Vols. 706-708

Abstract: A monolithic column of molecularly imprinted polymer was prepared by an in situ polymerization method with a new compound R, S 3-(4-Fluorophenyl) -2, 2-Dimethylcyclopane Carboxamide which has fluorin organic compound as the template. The molecular recognition capabilities of the prepared monolithic MIP were evaluated by separating the enantiomers. The characteristics of the column and the influences of mobile phases were studied. The results showed that the monolithic column has chiral recognition capability for the template and the enantiomers were baseline separated even in aqueous solution.

Abstract: The 95% of ethanol crude extract of aerial stem and rhizome of houttuynia cordata was sequentially extracted with petroleum ether, ethyl acetate, n-butyl alcohol and water. Antimicrobial activity and minimum inhibitory concentration (MIC) of the different extracts against Staphylococlus aureus, Escherichia coli, Bacillus subtilis, Aspergillus niger and Saccharomycetes were examined with filter paper method. And antimicrobial activity between aerial stem and rhizome was compared. The result showed that, among the extracts of aerial stem and rhizome of houttuynia cordata, with regard to antimicrobial activity, water extract was strongest against Staphylococlus aureus, and ethyl acetate extract was strongest against Escherichia coli, and n-butyl alcohol extract was strongest against Bacillus subtilis and Saccharomycetes, while each extract had no significant antimicrobial activity against Aspergillus niger. Moreover, the antimicrobial activity of rhizome was stronger than that of the aerial stem.

Abstract: A novel copolymer based on bromobenzene and 3,4-ethylenedioxythiophene (EDOT) was electrochemically prepared in boron trifluoride diethyl etherate (BFEE) via direct anodic oxidation of the monomer mixtures on indium-tin oxide working electrodes. The corresponding polymer was characterized by cyclic voltammetry and UV-vis spectroscopy. The copolymer had a very well-defined and reversible redox process. The band gap of the copolymer was calculated as 1.42 eV, respectively from the onset of π-π* transition of conjugated backbone. Furthermore, the copolymer exhibited multicolor electrochromism, high redox stability and reasonable response time.

Abstract: Olympic torches are the fantastic combination of successful design, appropriate materials and optimum processing which are the basic concept concepts in the major of Materials science and engineering. London Olympic torch was designed to be a three-sided pyramidal in shape, reflecting the features of the Olympic host country and the implication of designers. The material of Olympic torch selected aluminum alloys with a lightweight, high-strength, low thermal conductivity and environmentally friendly recycle; if low weight and high strength are key criteria for the torch, perhaps we can look forward to the incorporation of grapheme in the 2016 Olympic Games torch. The processing of Olympic torch involved laser cutting for 8000 holes and physical vapor deposition for gold-colored titanium nitride film on the surface of the aluminum plates, which embodied the best manufacturing route and the host country's technological capabilities.

Abstract: High-resolution synchrotron radiation x-ray absorption spectroscopy on Zn K-, Cd L3- and Te L3-edges for Cd1-xZnxTe ternary alloys with x = 0.10, 0.30, 0.50 and 0.90 are presented. A detailed analysis of the extended x-ray absorption fine structure using the IFEFFIT program, and the chemical bonds of Zn-Te are obtained, suggesting distortion of the Te sub-lattice. The x-ray absorption near-edge structure of the Zn K-, Cd L3- and Te L3-edge are investigated, and the electronic structures of Cd1-xZnxTe with various compositions are studied.

Abstract: Applying the appropriate ratio of hydrochloric acid and nitric acid mixed solvents, the aluminum and aluminum alloy products were completely digested, and then the digestion solution was diluted with water to a constant volume, and directly using inductively coupled plasma atomic emission spectrometry (ICP-OES) to test Ga and the content of which is from 0.005 to 1.0%. This paper has examined the effect of high aluminum matrix and coexisting elements on the interference of testing micro gallium, and by optimizing the parameters of the instrument detection such as gallium analytical line, detection integration region and synchronization background correction position, etc., effectively eliminated the spectral interferences of coexistence impurity elements. The method have optimized instrument working conditions of the plasma emission spectrometer, and taken matrix matching and synchronization background correction combination of technical measures to eliminate the matrix effect of aluminum products. The method is simple and practical, easy to operate, and avoid the complicated chemical separation and enrichment procedures, with fewer steps, shorter inspection cycle, wide detection range, high precision and accuracy. The results of the method for the determination of the gallium in the aluminum and aluminum products show that: the detection limit of 0.0002%, the background equivalent concentration of 0.00004% and the RSD is less than 2%, the recoveries is from 96.0% to 104.0%.

Abstract: τMicrowave dielectric properties of 0.95MgTiO₃-0.05CaTiO₃ ceramics and their performances as H-shaped microstrip patch antenna were investigated. Best values of dielectric constant (ε_r) and quality factor (Q×f) of 19.00 and 66800GHz, respectively, were obtained for the microwave ceramics sintered at 1300°C for 3h. A near-zero temperature coefficient of resonant frequency (τ_f) of -4.7ppm/°C was obtained for the ceramics with sintering 1280°C for 3h. A new kind of H-shaped microstrip patch antenna with two resonant frequencies was fabricated by using of this kind of ceramics as antenna substrate. The return loss bandwidth of the patch antenna was extended with the increasing of substrate thickness at both resonant frequencies of the antennas, around 1.530GHz and 2.750GHz, respectively.

Abstract: To investigate the protective effects and the possible molecular mechanisms of chlorogenic acid on H₂O₂-induced dysfunction and apoptosis in human umbilical vein endothelial cells (HUVECs). HUVECs were divided into three groups: H₂O₂ groups (0, 5, 10, 20, 50mM), chlorogenic acid (100nmol/L) groups and atorvastatin (10μmol/L) groups. The eNOS mRNA expression was measured by RT-PCR. The content of NO in the supernatant was detected by the nitrate reductase assay. Cells activity was evaluated by the MTT assay. The level of reactive oxygen species (ROS) in cells was measured using H₂DCF-DA as a fluorescence probe. Results demonstrated that H₂O₂ caused a significant down-regulation of eNOS mRNA expression and decreased the secretion of NO in a dose-dependent manner compared with the control group. Furthermore, H2O2 induced cell apoptosis, increased ROS accumulation. Nevertheless, these effects of H₂O₂ could be blocked by chlorogenic acid in chlorogenic acid pretreatment groups. CONCLUSION:chlorogenic acid can inhibite H₂O₂-induced dysfunction and apoptosis in HUVECs, which may be related to its effects on suppressing oxidative stress, up-regulating eNOS pathway. These results suggest the usefulness of chlorogenic acid particularly in the treatment of cardiovascular disease.

Abstract: In this study, AlF₃ was added into the Zinc flux and the spreading area of Zn20Sn of every flux formula was measured. The spreading area of Zn20Sn of different temperatures of the optimal content of the AlF₃ was measured as well. The result showed that the spreading area of Zn20Sn increased with the content of AlF₃ increasing when the content was below 2%. the spreading area of Zn20Sn decreased with content of AlF₃ increasing when the content of AlF₃ exceeded 2%. The spreading area of Zn20Sn was increased 126% than that of the matrix solder when the temperature was 470°C and the content of AlF₃ was 2%.

Abstract: Cu-32wt.%Zn alloy was subjected to equal channel angular pressing (ECAP) and subsequent low temperature annealing treatment, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion rate of the ultrafine-grained alloy decreases, in comparison with the coarse-grained alloy. Meanwhile, it is noted that the corrosion resistance of the sample subjected to ECAP can be further improved by relief annealing.