Advanced Materials Research Vols. 998-999

Abstract: Quantum mechanical calculations have been performed to study the equilibrium among the key intermediates (iminium ion, oxazolidione, and enamine) in the proline-catalyzed reactions under base-free and base-present conditions. The results confirmed that the tautomeric equilibrium among these species can be tuned by the basic additives. The computations satisfactorily rationalized the experimental observations and provide a clue on how to stabilize the enamine intermediates.

Abstract: Uniform and well-dispersed ellipsoidal BaWO₄:Dy³⁺ particles have been prepared via a simple hydrothermal method. The as-obtained particles are non-aggregated with narrow size distribution and are composed of closely packed nanoparticles. During the hydrothermal process, the chelating agent trisodium citrate plays an important role for the formation of BaWO₄:Dy³⁺ hierarchical ellipsoidal particles. The BaWO₄:Dy³⁺ phosphor shows intense yellow emission corresponding to ⁴F₉/₂-⁶H_13/2 transition of the Dy³⁺ ions under ultraviolet light excitation, which may find potential applications in fields of fluorescent lamps, display systems, and optoelectronic devices.

Abstract: The oxidation polymerization simplifies the brush plating process, by which a conductive polymer film is formed on Polyamide Engineering Plastics surface before direct brush plating. In the article, analysis is made on the various process parameters and the influence of the brush plating solution composition on deposition rate . And discussion has been done on the polyamide engineering plastics brush plating process , which includes three phases, namely preprocess, catalysis and brush-plating. the demand on brush-plating process is as following: The workpiece is connected to the positive; the working voltage is 14 V; the movement speed of the brush is from 0.04 m/s to 0.06 m/s; the temperature of brush-plating solution should remains at 80 °C; PH value is between 4.3 to 4.5.The test consequence shows that there are many advantages of brush-plating nickel-phosphorus alloy on the polyamide engineering plastics surface such as simple operating , brush-plating layer with high strength, no stripping and no cracks,and high abrasive resistance, all of which have greatly extended the life of polyamide engineering plastics service.

Abstract: In the 21st century, environmental pollution has become increasingly serious. Pollution control and management has been the major issue and must be resolved. In this paper, TiO2 as a representative oxide semiconductor photo catalytic material, which is an ideal environmental pollution cleaning product due to its unique properties. The low temperature magnetron sputter coating was employed to deposit Nanostructured TiO2 films on the surface of nonwovens and polymer fibers to functionalize the textile materials. The use of magnetron sputter coating not only overcame the problems of Nanoparticle aggregation as filling particles, but also shortened the production processes and eliminated the water pollution. The use of magnetron sputter coating, on the other hand, could cut the processing cost. This research explored the formation principle, preparation techniques, properties and reliability of the Nanostructured TiO2 deposited on the surface of textile substrates to meet the demands of the markets for functional textiles.

Abstract: Using the empirical formula with three free parameters recently proposed, ionization cross sections are given for the representation of cross sections for single ionization of free atoms from the ground stages by electron impact. Almost all experimental results can be approximated by this formula with 20% over the whole energy range between the threshold and 1 . All experimental results can be approximated with experimental error. The formula proposed is not suitable to regenerate the exact contour of fine structure in the ionization cross section curve. The probable error is estimated to be approximately 20%, but the error is larger than 40% and no fine structures are accounted for near the threshold.

Abstract: In this paper, using capillary zone electrophoresis method determined Vitamin C content in brown rice. 20 mmol/L borax solution and 20% acetonitrile concentration, 20kV voltage, 254 nm UV detection wavelength was chosen for electrophoretic analysis condition. Measured vitamin C content in brown rice was 0.043 mg/g (RSD=7.1%) (n=7).

Abstract: Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistence of the advanced hepatocarcinoma to chemotherapy. Curcumol (Cur), a novel compound extracted from rhizoma curcumae, exhibits various anticancer activities and can be treat hepatocarcinoma. However, the low solubility hinders development. We evaluate both the in vitro and in vivo antitumor activity of Cur-nanosuspension (Cur-N) relative to efficacy of bulk Cur. Cur-N with a particle size of 231.2 ± 7.2 nm and a zeta potential of −27.3 ± 0.6 mV, prepared by the high-pressure homogenization (HPH) technique. CCK-8 assay showed that Cur-N effectively inhibited the proliferation of H22 cells. In vivo studies also showed higher antitumor efficacy against H22 solid tumor bearing mice. These results suggest that the delivery of Cur-N is a promising approach for treating tumors.

Abstract: Repeating administration of methamphetamine (METH) can result in locomotor sensitization, a progressive increase in their psychomotor activating effects. l-Stepholidine (l-SPD), an alkaloid extract of the Chinese herb Stephania intermedia, is the first compound known to exhibit mixed dopamine D1 receptor agonist/D2 antagonist properties and is a potential medication for the treatment of drug addiction. Therefore, the effects of l-SPD on the hyperactivity, development and expression of METH-induced locomotor sensitization were investigated. The results indicated that l-SPD dose-dependently inhibited hyperlocomotion induced by acute METH and prevented the sensitized motor behavior induced by chronic METH administration. l-SPD likely acts as a D1 partial agonist and a D2 antagonist to produce its in vivo effects and may be a promising agent for treatment of METH addiction.

Abstract: Previous studies demonstrated that 20(S)-ginsenoside Rg3 (20S-Rg3) could effectively inhibit tumor cell proliferation as well as K⁺ channel currents expressed in xenopus oocytes. However, the effect of 20S-Rg3 on the growth of human glioma cells and the ion channels expressed in tumor cells was rarely reported in the literature. In the present study, we investigated the effect and the underlying mechanism of 20S-Rg3 on cell proliferation and apoptosis of human glioma U87-MG cells. In vitro results exhibited that 20S-Rg3 had potent cytotoxic effect and significantly inhibited the proliferation of U87-MG cells in a dose-and time-dependent manner. Typical arrest at G₂/M phase was induced, and the apoptosis rate of U87-MG cells was significantly higher in the 20S-Rg3 treatment group than in the control group. Electrophysiological results showed that 80 μmol/L 20S-Rg3 substantially inhibited voltage-gated K⁺ currents of U87-MG cells. Together, these results suggest that the suppression of voltage-gated K⁺ currents might play an important role in the 20S-Rg3-induced cell death, and these new findings provide useful data for further study of the antitumor effect of 20S-Rg3.

Abstract: In order to investigate the influence of electroacupuncture on heroin seeking behavior and the expression of CB2-Rs in the relapse-relevant brain regions, heroin self-administration rat model which represents the heroin relapse behaviors was developed with progressive fixed ratio program. The model rats were randomly divided into 3 groups: control group, heroin-addicted group and 2Hz electroacupuncture group (stimulating on acupoints zusanli and sanyinjiao). The expression of CB2-Rs in the relapse-relevant brain regions were assessed with immunohistochemistry technologies. The reinstatement of heroin seeking behavior induced by conditioned cue priming showed that compared with the heroin-addicted group, active pokes in the 2Hz electroacupuncture group decreased significantly (p<0.05). Compared with the control group, the expression of CB2-Rs in prefrontal cortex (PFC) and nucleus accumbens (NAc) was significantly decreased (p<0.05) in heroin-addicted group and increaseed significantly recover (p<0.05) in the 2Hz electroacupuncture group. Our present results showed that 2Hz-electroacupuncture could attenuate the conditioned cue-evoked heroin-seeking behavior and the inhibitory effect was mediated partially by the increase CB2-Rs expression in relapse-relevant brain regions in heroin-addicted rats.