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Tang X.,Anhui Vocational and Technical College
Procedia Engineering | Year: 2011

Next generation networks supporting multimedia applications include hybrid/integrated satellite-terrestrial network architectures require stringent QOS provisioning for fixed and/or mobile services. In this paper, we have described Integrated Network architecture and technical challenges for the system realization based on the ITU-R current work plan. We developed a cross-layer design based simulation framework in order to understand the impact of rain fade and mitigation due to DVB-S2 on the multimedia applications. our simulation network models include DVB-S2/RCS for the satellite segment and two scenarios for terrestrial segments namely WiMAX and WiFi. In particular, our simulations demonstrated the advantage of cross layer design in system capacity gains for VoIP users in hybrid network with WiMAX as terrestrial segment. Also our results show the impact of fading on applications such as video conferencing VoIP, HTTP, Data Base Query and FTP in terms of QOS parameters e.g. bandwidth allocation, end-to-end delay, delay variation. © 2011 Published by Elsevier Ltd.

Wang B.-H.,Anhui Vocational and Technical College | Zhu R.-Y.,Tianjin Polytechnic University
Wool Textile Journal | Year: 2013

Wool fiber modification by freeze treatment was carried out by placing wet wool fabric in a household regrigerator-freezer in this study. Chemical and mechanical properties of treated samples was analyzed and compared with that of untreated one's. Investigation results showed that diameter of wool fiber with freeze treatment increased and the structure of wool fibers became more looser, attributed to wool swollen caused by water migration and ice crystal growth during freezing treatment. Relative researches showed that wool samples with freezing treatment had more chemical activities and better low temperature dyeing effects compared with that of untreated samples, while the fabric tensile strength did not affected obviously, illustrating effectiveness of freezing treatment as a physical ways for wool modification.

Hao J.,Hefei University of Technology | Hao J.,Anhui Vocational and Technical College | Gong M.,University of Chinese Academy of Sciences | Wu Y.,Yancheng Teachers University | And 3 more authors.
Journal of Hazardous Materials | Year: 2013

By changing -COOH content in poly(acrylic acid-co-methacryloxypropyl trimethoxy silane (poly(AA-co-γ-MPS)), a series of PVA/SiO2 cation exchange membranes are prepared from sol-gel process of poly(AA-co-γ-MPS) in presence of poly(vinyl alcohol) (PVA). The membranes have the initial decomposition temperature (IDT) values of 236-274°C. The tensile strength (TS) ranges from 17.4MPa to 44.4MPa. The dimensional stability in length (DS-length) is in the range of 10%-25%, and the DS-area is in the range of 21%-56% in 65°C water. The water content (WR) ranges from 61.2% to 81.7%, the ion exchange capacity (IEC) ranges from 1.69mmol/g to 1.90mmol/g. Effects of -COOH content on diffusion dialysis (DD) performance also are investigated for their potential applications. The membranes are tested for recovering NaOH from the mixture of NaOH/Na2WO4 at 25 - 45°C. The dialysis coefficients of NaOH (UOH) are in the range of 0.006-0.032m/h, which are higher than those of the previous membranes (UOH: 0.0015m/h, at 25°C). The selectivity (S) can reach up to 36.2. The DD performances have been correlated with the membrane structure, especially the continuous arrangement of -COOH in poly(AA-co-γ-MPS) chain. © 2012 Elsevier B.V.

Jin J.,Anhui Vocational and Technical College
Wool Textile Journal | Year: 2015

Based on nylon-6, this article studies the effect of physical property on filament number of nylon yarn, ratios of warp and weft densities, dyeing process and finishing technology used on different type superfine nylon down fabrics which are produced by different weave designing, processing methods and technology. The optimized process methods and satiation concluded by experiment data can be for the practical producing reference. Tests show that as the increases of filament number, the tearing strength and downproofness ability will be promoted accordingly with the superfine nylon down fabrics. If the ratio of warp and weft densities approaches one under the fabrics of the same specification, the more tearing strength with the less slippage, the better downproofness ability. When the specification of yarn is the same under the same other conditions, the tearing strength and downproofness ability with finish treatment have advantages over. Compared with open dyeing using beam dyeing machine, the rope dyeing using flow dyeing machines has advantages on good effects of downproofness ability, slippage and the tearing strength. If the specification of yarn and other conditions keep the same, the tearing strength and downproofness ability done with aqueous polyurethane adhesive have advantages over that of other finish treatment while there is no difference on slippage.

Xuan F.,Anhui University of Science and Technology | Xuan F.,Anhui Vocational and Technical College | Liu J.,Hefei University | Xu T.,Anhui University of Science and Technology
Polymers for Advanced Technologies | Year: 2011

Charged hybrid membranes with anionic- or cationic-exchange groups have attracted increasing interest due to their higher thermal stabilities and structural flexibilities which are considered suitable for use in some harsh conditions, such as higher temperature and strongly oxidizing circumstances, for industrial applications. To develop new routes to synthesize the negatively charged hybrid membranes, a series of hybrid membranes were prepared via free radical polymerization of glycidylmethacrylate (GMA) and γ-methacryloxypropyl trimethoxy silane (MPTMS) monomers, and ring-opening of epoxide to create negatively charged -SO3H groups in the polymer chains. The fundamental properties of these prepared membranes were characterized through TGA, ion-change capacity (IEC), and MALDI-TOF mass spectra. TGA showed that the thermal degradation temperature of these membranes could reach up to 300°C and the temperature of the first endothermic peak decreased with an increase in the content of -SO3H groups. IEC measurements showed that their IECs were within the range of 0.22-0.35mmolg-1. MALDI-TOF spectrometry indicated that the incorporation of GMA into the hybrid matrix could improve the structural stability of the membranes. These findings demonstrated that the ion-exchange properties and structural stability of negatively charged hybrid membranes can be conveniently controlled by adjusting the GMA moiety in the hybrid matrix. © 2009 John Wiley & Sons, Ltd.

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