Papers by Keyword: Structure Characterization

Abstract: Titanium alloys due to their low density and high mechanical properties are a group of materials that are being used willingly nowadays. A promising method of titanium heat treatment is laser surface alloying. Process parameters like laser beam power, its transverse speed, amount of alloying elements and shield gas, have influence on the material. Different chemical composition and morphology can be achieved resulting in a change of properties on the surface of the material. The paper presents the investigation of titanium GRADE 1 processed with iron‐nickel powder using laser alloying. The treatment was performed using a high power diode laser. Different laser beam power values were used.

Abstract: Powder bed fusion (PBF) is an additive manufacturing technique, which allows to build complex functional mechanical parts layer-by-layer, starting from a computer-aided design (CAD) model. PBF is particularly attractive for biomedical applications, where a high degree of individualization is required. In this work, the microstructure of two biomedical alloys, namely Co-Cr-Mo and Ti-6Al-4V, were studied by X-ray diffraction and electron microscopy techniques. Hardness and tensile tests were performed on the sintered parts.

Abstract: New organic silicon nano-materials which has photo-curing performance was prepared by sol-gel method using γ-methacryloxy propylt rimethoxy silane as the starting materials. The micro-structures of the organic silicon nano-materials were characterized by FTIR and NMR. TEM was used to observe the nanometer particle size and the distribution of the nanometer particle in the organic silicon nanomaterials. The photo-curing properties of the new materials were tested. Results show that the new organic silicon nano-materials has uniform particle distribution and side chain of methacryloxy groups and can be UV-curing.

Abstract: A novel polypropylene strong acid cationic exchange fiber (SACEF) was prepared by sulphonation reaction of polypropylene graft styrene (PP-g-St) fiber. The structure of SACEF was characterized through IR, TG, DTG, EA and SEM testing. The physicochemical properties of PSACEF, including adsorption capacity, adsorption dynamics, water content, and regeneration stability were evaluated. The results showed that the adsorption capacity of SACEF was 4.42 mmol·g^-1. Infrared spectra indicated that hydrogen on the benzene ring was substituted by sulfuric acid group. TG and DTG confirmed that SACEF was more stable under the 250 °C. The adsorption dynamics suggested that the adsorption on SACEF was fast and it nearly reached equilibrium within 1 min. The water content of SACEF was 55%~60%. SACEF showed good regeneration performance. The adsorption capacity was constant after being used many times.

Abstract: Melamine formaldehyde (MF) resin and its derivatives are always considered to be an excellent flame retardant material, which has a wide application in the flame retardant fabric, thermal insulation and high temperature filter Materials etc. The melamine formaldehyde resin (MF) and polyvinyl alcohol (PVA) blend electrospinning were studied in this work. MF-PVA electrospun fiber membrane was successfully prepared, and the limit oxygen index (LOI), scanning electron microscopy (SEM), infrared spectrum (IR) and X-ray diffraction (XRD) have been used to analyze and characterize the fiber. The results show that: The blending fiber is endowed with effective flame retardant property by the amino group and triazine ring group in MF/PVA fibers, and the LOI reaches 28~31. The MF and PVA blend fiber showed best uniformity when the blending solid content ratio of MF-PVA is 1:1. MF/ PVA blend fiber has certain crystallization capacity, which influences both the mechanical properties and flexibility of blending fiber.

Abstract: A new bi-capped Keggin heteropoly molybdovanadated derivative, [Co (en)₃]₂[SiMo₈V₆O₄₂]∙6H₂O (1) (en = ethylendiamine) has been hydrothermally synthesized and structurally characterized by the elemental analysis, IR, XPS and single crystal X-ray diffraction. The crystal structure analysis reveals that compound 1 consists of [Co (en)₃]²⁺ transition metal coordination fragment and the [SiMo₈V₆O₄₂]^4- building blocks, which are linked together via hydrogen-bonding interactions to form a new 3-D supramolecular networks.

Abstract: A new supramolecular compound, [Co (en)₃]₂[H₃PMo₈V₆O₄₂]∙5H₂O (1) has been hydrothermally synthesized and structurally characterized by the elemental analysis, IR and single crystal X-ray diffraction. Compound 1 consists of [Co (en)₂]²⁺ transition metal coordination fragment, [H₃PMo₈V₆O₄₂]^4- building blocks and crystal water molecules, which are linked together via hydrogen-bonding interactions to form a new 3-D supramolecular networks. The degradation of methylene blue (MB) under UV-vis irradiation with 1 as the heterogeneous photocatalyst has been investigated, showing a good photocatalytic property of 1 for MB degradation.

Abstract: In order to obtain an important azobenzene liquid crystal with high birefrience, click chemistry reaction was used to preparation the compound. In this paper, the novle azobenzene liquid crystal was synthesized by (4-Ethynyl-phenyl)-(4-trifluoromethyl-phenyl)-diazene and C₈H₁₇Br as raw materials. In addition, the synthesized compound was characterized by FT-IR and ¹H-NMR to confirm the consistent structure, and the liquid crystal phase behaviors of phase sequences were investigated by polarizingmicroscope (POM).

Abstract: Seven novel aryloxy-acetyl ferrocene derivatives were parallel synthesized under microwave irradiation conditions from chloroacetyl ferrocenes and substituted phenols with the aim of obtaining potential antioxidant agents. The target compounds were identified by IR, ¹H NMR, MS and elemental analysis, and their antioxidant assays indicated that all the aryloxy-acetyl ferrocenes had certain effect on eliminating 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Their antioxidation activity significantly improved when rising the temperature until the temperature was 35°C. The structure-activity relationship analysis showed the electron-donating substituted aryloxyl group could strengthen the radical scavenging abilities, while the electron-withdrawing effects would block antioxidant abilities.

Abstract: Ultrathin silica films were grown on polyimide substrates using surface sol-gel method and the film growth process was characterized by ellipsometry, atomic force microscopy, X-ray photoelectron spectroscopy, Fourier transformed infrared spectroscopy. The polyimide substrates were pretreated by chemical process for promoting the growth of silica film. On the modified polymide surface, the growth of silica films shows an island-like growth type, but not a lay-by-lay process. Moreover, the deposited silica films are not a strict SiO₂ film.