Bending behavior of coated yarns

Cotton yarns were coated with a polymer solution to hold surface fibers to the yarn body, which caused fiber-fly generation during knitting process. The physical property of the coated yarn, especially a bending rigidity was investigated in order to evaluate the performance of the coated yarn during knitting. SEM images showing the surface condition of the coated yarn demonstrated that the thickness of a coating material increased as the concentration of the coating solution increased. The results of the bending rigidity measured using KES-FB2 system showed that the bending rigidity of the coated yarn increased as the concentration of the coating solution increased. The results also revealed the possibility that yarn coated with a low amount of coating material should be employed for further research of reducing fiber-fly generation during knitting process.     

Effects of spinning processes on HVI fiber characteristics and spun yarn properties

The effects of opening, carding, and repeated drawings on single fiber and bundle cotton characteristics were studied by employing Mantis®, AFIS® and HVI Testers. Some of the significant changes in single fiber properties were found to be due to process parameters as well as the changes in the fiber crimps, parallelness of fibers within HVI beards, and the actual changes in the tensile properties of the fibers. The study showed that the HVI test data taken just prior to spinning had the highest correlation with the yarn tensile properties. Based on the study results, we point out the potential of HVI for future quality and process control in spinning by recommending a set of expanded HVI output that is more scientific and comprehensive for the future control needs.     

Formation,characterization, and glucose response in mice to rice starch with low digestibility produced by citric acid treatment

The optimum conditions for producing rice starch enriched in slowly digestible and resistant fractions by citric acid treatment determined by a response surface methodology (RSM) model equation, were: reaction temperature, 128.4 °C; reaction time, 13.8 h; and citric acid, 2.62 mmol/20 g starch. The slowly digestible and resistant starch fractions of the optimally acid-treated rice starch totalled 54.1%, which was 28.1% higher than the control. The slowly digestible and resistant fractions of the acid-treated rice starch did not differ significantly after heat treatment, whereas those of raw rice starch decreased by 49.6–63.8%, depending on the type of heat treatment (cooking at 100 °C or autoclaving). The slowly digestible fraction of the acid-treated starch increased by 8.9–14.2%. After autoclaving, the glucose response of the acid-treated starch was lower than untreated starch, but similar to that of Novelose 330. After heat treatment, the rate of blood glucose decrease was slower for the acid-treated starch than for Novelose 330. Compared to raw rice starch, the acid-treated starch exhibited increases in apparent amylose content, blue value, dextrose equivalent, cold-water solubility and transmittance, and decreases in wavelength of maximum absorbance, viscosity, and gel-forming ability.     

Application of micronutrients to citrus trees through microirrigation systems

Using conventional soil and foliar spray applications to correct micronutrient deficiency in citrus has not been completely satisfactory. Therefore, this study was developed to test the effectiveness of micronutrient application through microirrigation (fertigation) at rates similar to those recommended for foliar spray application. Three field experiments were conducted on ‘Valencia’ orange [Citrus sinensis (L.) Osb.] trees to study the absorption of Fe, Mn, Zn, and Cu by periodically analyzing leaf samples. The effectiveness of fertigation with micronutriems was found to depend on the fertilizer source. Application of chelated Fe, Mn, and Zn through irrigation systems increased the concentrations of these micronutrients in the leaves. The nitrate forms of Fe, Mn, and Zn were ineffective, as was the sulfate form of Zn. The sulfate form of Mn was occasionally effective, but the sulfate form of Cu was very effective. The application of chelated micronutrients through fertigation shows promise in central Florida.     

Seasonal variation of soil respiration rates in a secondary forest and agroforestry systems

Agroforestry systems are widely practiced in tropical forests to recover degraded and deforested areas and also to balance the global carbon budget. However, our understanding of difference in soil respiration rates between agroforestry and natural forest systems is very limited. This study compared the seasonal variations in soil respiration rates in relation to fine root biomass, microbial biomass, and soil organic carbon between a secondary forest and two agroforestry systems dominated by Gmelina arborea and Dipterocarps in the Philippines during the dry and the wet seasons. The secondary forest had significantly higher (p < 0.05) soil respiration rate, fine root biomass and soil organic matter than the agroforestry systems in the dry season. However, in the wet season, soil respiration and soil organic matter in the G. arborea dominated agroforestry system were as high as in the secondary forest. Whereas soil respiration was generally higher in the wet than in the dry season, there were no differences in fine root biomass, microbial biomass and soil organic matter between the two seasons. Soil respiration rate correlated positively and significantly with fine root biomass, microbial biomass, and soil organic C in all three sites. The results of this study indicate, to some degree, that different land use management practices have different effects on fine root biomass, microbial biomass and soil organic C which may affect soil respiration as well. Therefore, when introducing agroforestry system, a proper choice of species and management techniques which are similar to natural forest is recommended.     

Performance characteristics of a conformal ultra‐wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non‐resectable tumours

Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth of 4.59 cm compared to 2.74 cm for the flat antenna. Clinical use of the antenna was then evaluated in six animals with locoregionally advanced solid tumours receiving adjuvant chemotherapy. During clinical applications, therapeutic temperatures were achieved at depths ≥4 cm. Objective responses were seen in all patients; tissue toxicity in one case limited further therapy. This antenna provides compact, efficient, focused and deep‐penetrating clinical hyperthermia for the treatment of solid tumours in veterinary patients.     

Preferences of urban dwellers on urban forest recreational services in South Korea

This paper aims to investigate the preferences of urban dwellers for various attributes of urban forests, with an emphasis on forest recreational services. A choice experiment was conducted using face-to-face interviews with 823 urban dwellers in 2010. Urban forest attributes such as trails, slope, biodiversity, environmental education programs and entrance fees were found to influence Korean citizens’ preferences regarding urban forests. Among the six urban forest attributes, biodiversity was the most influential among Korean urban dwellers in their choice of urban forest recreation. Three latent groups with relatively homogeneous preferences over various urban forest attributes were identified. Residential area, family composition and the purpose of their visit determined group membership. It was notable that the preferences of urban forest recreationists differ from the general preferences of visitors to forests located in remote areas. Urban forest planning and management should consider the attributes of urban forests and the preferences of citizens visiting urban forests to improve urban dwellers’ welfare.     

Spectroscopic Analyses on Chain Structure and Thermal Stabilization Behavior of Acrylonitrile/Methyl Acrylate/Itaconic Acid-based Copolymers Synthesized by Aqueous Suspension Polymerization

We have synthesized a series of copolymers with different compositions of acrylonitrile (AN, 80–100 wt%), methyl acrylate (MA, 4–20 wt%) and itaconic acid (IA, 0–3 wt%) by using an efficient aqueous suspension polymerization, and have investigated the molecular structure and thermal stabilization behavior of PAN homopolymer, AN/MA-based bipolymers, and AN/MA/IA-based terpolymers by adopting ¹H/¹³C-NMR and thermal FT-IR analyses. The viscosity-average molecular weight of the synthesized polymers were measured to be ~263,000 g/mol. The reactivity ratios of AN and MA for all the copolymers were evaluated to be 0.99 and 1.05, respectively. Accordingly, the output compositions of the synthesized copolymers were quite consistent with the input monomer compositions. The ¹³C NMR analysis revealed that all the synthesized polymers have an atactic chain configuration, regardless of the feed composition. The structural evolutions during the thermal stabilization process of the copolymers in air environment were characterized by monitoring the temperature-dependent changes of characteristic absorbance bands at 2240 cm^-1 (C≡N), 1595 cm^-1 (C=N) and 1660 cm^-1 (C=O) with aid of thermal FT-IR spectroscopy. It was found that the IA unit in the terpolymers accelerated the oxidation and cyclization reactions, unlike the retarding effect of MA unit, and that the onset temperatures of the oxidation reaction of the copolymers with IA unit was lower than that of the cyclization reaction.     

Inherently Flame Retardant Nylon 6 Nanocomposite Fibers

In this study, inherently flame retardant nanocomposite nylon 6 fibers infused with nanoclay and intumescent additives were compounded and melt-spun. Two approaches were adopted to mitigate the loss of mechanical properties typically observed nanocomposite fiber systems: (a) additive particle size reduction; and (b) elastomer toughening of the nanocomposite system. As a result, the ductility of the FR nanocomposite formulations was improved significantly. Structural and morphological characterization of the melt-spun fibers using TEM and XRD demonstrated good dispersion of the additives and exfoliation of the nanoclay platelets. Microscale Combustion Calorimetry analysis demonstrated effective reduction of heat release capacity and thus significant enhancement of flame retardant performance of the compounded fibers.