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Sound absorption properties of polyamide 6 (PA6) nanofibre webs and a widely used sound absorption foam coated with nanofibre webs have been investigated. Initial studies have focused on the electrospinning by using PA6 polymer to obtain uniform and bead-free nanofibres. Thereafter, nanofibres are electrospun on an absorption foam through two spinning durations of 10 h and 20 h. Thicknesses, mass per unit area values, porosities, pore sizes, and Brunauer-Emmet-Teller surface areas of the webs are determined. At characterization stage, sound absorption coefficients of pure nanofibre webs, pure foam, and foams enhanced with nanofibre webs are measured by acoustic impedance tube method. Noise reduction coefficients (NRC) are also calculated. Sound absorption coefficients at 6400 Hz are observed as 0.76 and 0.74 for nanofibre webs electrospun during 10 h and 20 h respectively. The NRC values are found as 0.189, 0.197 and 0.192 for pure foam sample and nanofibre webs electrospun during 10 h and 20 h respectively. Overall results of the study indicate that moderate mid-high frequency sound absorption and noise reduction coefficients are obtained by using the nanofibre web coated foams. [ABSTRACT FROM AUTHOR]

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After washing cycles, textiles having minimum deformation, maximum dimensional stability and the same performance of an unused product are major expectations of customers. This study examined the effects of washing cycles on the cyclic deformation of elastane knitted fabrics in detail. 12 knitted fabrics with two different linear densities of viscose yarn and three different polyamide/elastane gimped yarn of two different tightness levels (normal and tight) were used in the experiments. M&S P15A test method were used to evaluate the cyclic deformation of unwashed and washed fabrics (0, 5, 15 and 25 cycles) for four different recovery time periods (0 min, 2 min, 30 min and 24 h). Dimensional change, tightness factor and mass per unit area values were also examined in order to investigate the residual deformation of the fabrics after each washing stages. Consequently, it is determined that the fabrics having 21 tex viscose ground yarn and 78dtex20f elastane gimped yarn with higher setting show less residual extension (%). 5 and 15 washing cycles and a 30 min. recovery time are found significant for all repeated washings. [ABSTRACT FROM AUTHOR]

Old growth mangroves in existing protected areas store more carbon than restored forests or plantations. Carbon storage in such forests has economic value independent of additionality, offering opportunities for policy makers to ensure their maintenance, and inclusion in climate change mitigation strategies. Mangrove forests of the Everglades National Park (ENP), South Florida, though protected, face external stressors such as hydrological alterations because of flooding control structures and agriculture impacts and saltwater intrusion as a result of increasing sea level rise. Moreover, decreased funding of Everglades’ restoration activities following the recent economic crisis (beginning 2008) threatens the restoration of the Greater Everglades including mangrove dominated coastal regions. We evaluate several economic and ecological challenges confronting the economic valuation of total (vegetation plus soil) organic carbon (TOC) storage in the ENP mangroves. Estimated TOC storage for this forested wetland ranges from 70 to 537 Mg C/ha and is higher than values reported for tropical, boreal, and temperate forests. We calculate the average abatement cost of C specific for ENP mangroves to value the TOC from $2–$3.4 billion; estimated unit area values are $13,859/ha–$23,728/ha. The valuation of the stored/legacy carbon is based on the: 1) ecogeomorphic attributes, 2) regional socio-economic milieu, and 3) status of the ENP mangroves as a protected area. The assessment of C storage estimates and its economic value can change public perception about how this regulating ecosystem service of ENP mangrove wetlands (144,447 ha) supports human well-being and numerous economic activities. This perception, in turn, can contribute to future policy changes such that the ENP mangroves, the largest mangrove area in the continental USA, can be included as a potential alternative in climate change mitigation strategies. [ABSTRACT FROM AUTHOR]

Testing the thermal properties of thermal interface material (TIM) has been a big challenge for decades. Recent development trends made this challenge even bigger, as now the values that have to be measured are extremely small. In this paper, we present a newly developed TIM tester equipment that is targeting to overcome all the problems that present industrial TIM testing methods face. The main idea behind our design is to use the capabilities of microelectronics in order to make small sized sensors both for temperature and heat-flux sensings. This way it is possible to place these sensors in the closest proximity of the measured sample. This paper presents details of all the technical solutions of the newly developed static TIM tester that is capable to measure Rth of unit area values in the order of 0.01 K cm² / W with good accuracy. Special attention is made to analyze and eliminate the possible sources of measurement inaccuracy. A number of measurement examples prove the usability of the developed measuring instrument. [ABSTRACT FROM AUTHOR]