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Mechanical Properties Of 3D-Structure Composites Based On Warp-Knitted Spacer Fabrics

Chen S., Long H. R., Liu Y. H., Hu F. H.

Autex Research Journal

2015

Vol. 15, no. 2

127--137

In this paper, the mechanical properties (compression and impact behaviours) of three-dimension structure (3D-structure) composites based on warp-knitted spacer fabrics have been thoroughly investigated. In order to discuss the effect of fabric structural parameters on the mechanical performance of composites, six different types of warp-knitted spacer fabrics having different structural parameters (such as outer layer structure, diameter of spacer yarn, spacer yarn inclination angle and thickness) were involved for comparison study. The 3D-structure composites were fabricated based on a flexible polyurethane foam. The produced composites were characterised for compression and impact properties. The findings obtained indicate that the fabric structural parameters have strong influence on the compression and impact responses of 3D-structure composites. Additionally, the impact test carried out on the 3D-structure composites shows that the impact loads do not affect the integrity of composite structure. All the results reveal that the product exhibits promising mechanical performance and its service life can be sustained.

Analysis of essential oil of Nardostachys chinensis Batal by GC-MS combined with chemometric techniques

Wang F., Liu S., Luo M. Y, Qin Y., Lei P, Liu Y. H, Liang Y. Z

Acta Chromatographica

2015

Vol. 27, no. 1

157--175

The essential oil extracted from Nardostachys chinensis Batal (NCB) was analyzed by gas chromatography-mass spectrometry (GC-MS) combined with two chemometric resolution methods (CRM), heuristic evolving latent projections (HELP), and selective ion analysis (SIA). Qualitative analysis was performed by comparing the obtained pure mass spectra with those in National Institute of Standards and Technology (NIST) mass spectra database. Identification of some compounds was assisted by comparison of programmed temperature retention indices (PTRIs). The quantitative results were obtained by overall volume integration (OVI). A total of 69 compounds in the essential oil of N. chinensis Batal were identified, accounting for 93.98% of the total content. The major compounds were (−)-spathulenol, epiglobulol, trans-longipinocarveol, and patchouli alcohol which contribute to the antimicrobial and antioxidant activity. The results showed that the efficiency and reliability were greatly improved by use of chemometric techniques and programmed temperature retention index as assistants of GC-MS in identification of the plant essential oil.

Graft copolymerization of methyl acrylate onto sodium alginate initiated by potassium diperiodatocuprate(III)

Liu Y. H., Li Y., Yang L., Liu Y., Bai L.

Polimery

2005

T. 50, nr 1

37-42

Graft copolymerization of methyl acrylate onto sodium alginate initiated by potassium diperiodatocuprate(III)Summary - A novel redox system, potassium diperiodatocuprate(III) (DPC) - sodium alginate (SA), was employed to initiate the graft copolymerization of methyl acrylate (MA) onto SA in alkali medium. The effects of reaction variables, such as the initiator concentration, the ratio of monomer and SA, SA backbone concentration, as well as temperature and time, were investigated, and the grafting conditions were optimized. Graft copolymers with both high grafting efficiency and high part of grafting were obtained, which indicated that DPC-SA redox system is an efficient initiator for this graft copolymerization. The structures and the thermal stability of SA and SA-g-PMA were characterized by scanning electron microscope (SEM), infrared spectroscopy (IR) and thermogravimetric analysis (TGA). A mechanism is proposed to explain the generation of radicals and the initiation.

Do inicjowania kopolimeryzacji szczepionej akrylanu metylu (MA) na alginianie sodu (SA) w środowisku alkalicznym zastosowano nowy układ redoks-dinadjodanomiedzian(III) potasu (DPC)/SA. Zbadano wpływ stężenia DPC i SA, stosunku masowego MA/SA, a także czasu (15-55 min) i temperatury (20- 60 oC) reakcji na sumaryczną konwersję (C), wydajność szczepienia (GE) oraz procentowy stopień szczepienia (PG) (rys. 1-5). Ustalono warunki, w których reakcja szczepienia przebiega z dużymi wartościami GE i PG. Strukturę zarówno wyjściowego SA, jak i produktu szczepienia (SA-g-PMA) scharakteryzowano metodami SEM oraz FT-IR. Metodą TGA określono stabilność cieplną obydwu tych substancji stwierdzając, że SA-g-PMA jest wyraźnie lepszy pod tym względem od wyjściowego SA. Zaproponowano mechanizm badanej reakcji wyjaśniający powstawanie inicjujących ją rodników.