Advanced Materials Research Vol. 528

Abstract: In order to obtain a nanocrystalline and amorphous structure in the Mg2Ni-type alloy, the Ni in Mg2Ni alloy has been partially substituted by M (M=Co, Cu), and the melt spinning has been used to fabricate the Mg20Ni10-xMx (M=Co, Cu; x=0-4) hydrogen storage alloys. The microstructures of the alloys were characterized by XRD, SEM and HRTEM. The effects of substituting Ni with M (M=Co, Cu) on the gaseous and electrochemical hydrogen storage kinetics of the as-spun alloys were investigated. The results indicate that the as-spun (M=Co) alloys display a nanocrystalline and amorphous structure, while the as-spun (M=Cu) alloys hold an entire nanocrystalline structure, suggesting that the substitution of Co for Ni facilitates the glass formation in the Mg2Ni-type alloy. The substitution of M (M=Co, Cu) for Ni exerts a trifling impact on the hydriding kinetics of the alloys, but it renders a marked enhancement of dehydriding capacity and kinetics. Furthermore, the measurements of the high rate discharge ability (HRD) and the hydrogen diffusion coefficient (D) as well as the electrochemical impedance spectra (EIS) of the alloys exhibit that the electrochemical kinetics of the as-spun (30 m/s) alloys is significantly ameliorated by substituting Ni with M (M=Co, Cu).

Abstract: Gd and Sb doped SnO2 conductive nanoparticles were prepared by the coprecipitation method with SnCl4•5H2O, SbCl3 and Gd2O3 as the raw materials. The crystal phase and structure of the prepared conductive nanoparticles were characterized by FTIR, XRD and TEM techniques, respectively. The resistivity of the prepared conductive nanoparticles was 0.29 Ωcm; FTIR spectrum showed that the vibration peak are wide peak in 723 cm-1～451cm-1, the Gd and Sb doped SnO2 conductive nanoparticles have intense absorption in 4000 cm-1～1600 cm-1; Gd and Sb doped SnO2 have a structure of tetragonal rutile; complex doping is achieved well by coprecipitation method and is recognized as replacement doping or caulking doping; TME shows that the particles were weakly agglomerated, the size of the particles calcined at 800°C ranged approximately from 10 to 30 nm.

Abstract: Objective In order to increase the Paeonol dissolution and content, cortex moutan were smashed into nanoparticles, and the dissolution and content were compared by microscopy before and after super-micro-particle pulverization. Methods Super-micro-particle pulverization and general grinding were used to broke Cortex moutan into particles. The microscopic morphous characteristics of the before- and after- ultra-disintegration particles were compared by microscopy. Methods of HPLC was used to determine the content and dissolution of Paeonol with different grinding conditions. Methods of precipitation and funnel way were used to examine the stability and fluidity of cortex moutan nano-particles. Results Cortex moutan powder after super-micro-particle pulverization appears sphere or like-sphere, and its average size is 200nm~300nm. After the superfine grinding Paeonol dissolution increases 76.19% in comparison with without nano pulverization. The nanoparticle rest angle is θ=33°.The precipitation ratio of Cortex moutan powder with general grinding is 0.28 at 24h, and the precipitation ratio of its nano-power has been to 0.98 at 60min. Conclusion Paeonol dissolution, stability and fluidity of Cortex moutan nanoparticles were improved greatly and this nanoparticles is beneficial to industrial production for traditional Chinese medicine.

Abstract: To prepare out a novel preparation of liuweidihuang which effectively preserves Paeonol, Ursolic acid and Polysaccharides, and the preparation process should be scientific, lower-price and simple. The microscopic characteristics and its physicochemical properties of super-micro-particle of liuweidihuang from above process were also discussed. Methods According to the therapeutic and physicochemical properties of materials in liuweidihuang, the processed technology is as follow: Ripe rehmannia glutinosa,Tuckahoe and Alisma digitalis were boiled for 4.5h., the root bark of the peony tree(Paeonia suffruticosa), dogberry and yam were smashed to nanoparticles. Then select the reasonable method to drying the mixture. The microscopic shape characteristics of the before- and after- broken particles was compared. Paeonol content and dissolution were determined by HPLC. The stability and fluidity of liuweidihuang nanoparticles were examined by precipitation and funnel way. Results The approach of prepared liuweidihuang nano-microcapsules is scientific, lower-price and simple. The average size of processed super-micro-particle of liuweidihuang is 400±46nm. The hardness of the table is 9.7kg/cm2. The thickness of the table is 0.6cm. The friability of the tablet is ＜1%. Each tested item complied with standards of troches of Chinese medicine, and it is beneficial to industrial production for Chinese medicine.. Conclusion The nano-microcapsule is dispersive, desiccative, mobilizable, stable and three times concentrated than traditional pills of Liuweidihuang. It also can be used to produce different forms of drugs in the market.

Abstract: Composite powder was obtained from nanometer TiO₂ combined with honokiol or quercetin. The linking-pattern, UV absorbance and antimicrobial performance were studied in this paper. The results showed that the primary linking-pattern between nano-TiO₂ and honokiol or quercetin is mainly in physical adsorption with little in chemical adsorption. The absorbance of the composite powder becomes stronger than the precursor and the range of UV absorbance range to ultraviolet rays extends dextrad. The composite powder is a kind of high grade material for making multi-functional product with its antimicrobial performance and properties of broad-spectrum sunblock.

Abstract: Packaging process is one of the main manufacturing steps in the wafer fabrication industries. However, nano-particles would be produced during the packaging process. The produced nano-particle-contained wastewater has characteristics of dark color and high turbidity. Because the nano-particles would usually result in the clogging of the membrane filtration system when it is used for water treatment and reclamation, the application of a pre-treatment system is required to extend the membrane life. The objective of this study was to develop a pre-treatment system for packaging wastewater treatment before membrane system was applied for further water quality improvement. In this laboratory-scale study, a hybrid treatment system containing a chemical coagulation/flocculation followed by ultra-filtration (UF) membrane technology was developed for the wafer fabrication wastewater treatment. The chemical coagulation/flocculation unit was used as the pre-treatment process to improve the efficiency of the following ultra-filtration (UF) membrane system. The packaging wastewater was collected from a wafer fabrication factory and used to evaluate the feasibility of the coagulation/flocculation process on nano-scale particle removal. Results show that approximately 98% of turbidity could be removed at pH 7 when 2.2 mg/L of polyaluminum chloride (PAC) (used as coagulant) and 0.5 mg/L of polyacrylamide (cPAM) (used as flocculant) were added during the coagulation/flocculation process. Results indicate that the coagulation/flocculation is a feasible pre-treatment process for nano-particle removal before UF membrane is applied for further water purification. Results from this study will be helpful in designing a scale-up system for practical applications.

Abstract: During the broadband viscoelasticity measurement process, when the frequency of the excitation force become high relative to the resonant frequency or the bandwidth of the instrument dynamics, the adverse instrument dynamics is motivated, which causes the cantilever resonance and generates large measurement errors in the measurement data. To solve this problem, an approach to suppress the cantilever resonance on the broadband viscoelasticity measurement is proposed. Firstly, Atomic force microscope (AFM) system dynamic is analyzed by using a dynamic signal analyzer (DSA) in the z-axis. And a notch filter is designed as a prefilter of the AFM system to filter the input drive voltage in order to offset the resonance peak in the AFM model. Secondly, an adaptive filter based on LMS is designed to further eliminate the residual cantilever resonance effects on the complex compliance of soft materials, referring to the Hertz contact model. Finally, the proposed approach is illustrated by implementing it to remove the cantilever resonance effects on the broadband viscoelasticity measurement of a polydimethylsiloxane (PDMS) sample using AFM.

Abstract: PLGA nanoparticles (PLGA-NPs) are being extensively studied as drug carriers for their controlled release, biodegradability and biocompatibility. This study evaluated the cellular uptake of PEGylated PLGA-NPs in Hela cells. MePEG-PLGA (5%-15%) was used to prepare PEG modified PLGA nanoparticles (PEG-PLGA-NPs), and the fluorescent marker DiI was encapsulated in the nanoparticles for the visualized analysis. The nanoparticles were characterized for surface morphology, particle size, zeta potential, and for cellular uptake by Hela cells. Results showed that PLGA nanoparticles were lowly cytotoxic and could be uptaken by Hela cells freely. PEG-PLGA-NPs had faster cellular uptake than that of nude PLGA nanoparticles, especially 10%PEG-PLGA-NPs. It suggested that the surface modification of PLGA-NPs by PEG notably improved the cellular uptake.

Abstract: With carbon nanotube as cold cathode, the field emission display based on the improved film-electrode was fabricated. The indium tin oxide film covered on the glass surface was etched to form the film-electrode. For one film-electrode stripe, the left bar electrode and the right bar electrode were formed on the both side of the bottom electrode. The carbon nanotube would be prepared on the bottom electrode surface. The cathode covering layer fabricated with the sintered insulation slurry would cover the left and right bar electrodes. It was confirmed that the emission current could be controlled by the formed electric-field with the improved film-electrode.

Abstract: Density functional theory (DFT) calculations were performed to investigate the structures of trifluoromethyl silsesquioxanes Si_2nO_3n(CF₃)_2n (n=1-5). Our study focuses on the structures, stabilities, and electronic properties of the trifluoromethyl silsesquioxanes. The large HOMO–LUMO gaps, which range from 5.38 to 8.02 eV, imply optimal electronic structures for these molecules.