Missing OH reactivity in a forest: evidence for unknown reactive biogenic VOCs

Forest emissions of biogenic volatile organic compounds (BVOCs), such as isoprene and other terpenes, play a role in the production of tropospheric ozone and aerosols. In a northern Michigan forest, the direct measurement of total OH reactivity, which is the inverse of the OH lifetime, was significantly greater than expected. The difference between measured and expected OH reactivity, called the missing OH reactivity, increased with temperature, as did emission rates for terpenes and other BVOCs. These measurements are consistent with the hypothesis that unknown reactive BVOCs, perhaps terpenes, provide the missing OH reactivity.     

Effects of competition between phase separation and ester interchange reactions on the phase behavior in a phase-separated immiscible polyester blend: Monte carlo simulation

The effects of rate ratio of phase separation to ester interchange reactions and the repulsive pair interaction energy on the phase behavior in a phase-separated immiscible polyester blend are investigated using a Monte Carlo simulation method. The time evolution of structure factor and the degree of randomness are monitored as a function of homogenization time. When the phase separation is dominant over ester interchange reactions, the domain size slowly increases with homogenization time. However, when the pair interaction becomes less repulsive, the domain size does not significantly change with homogenization time. On the other hand, when ester interchange reactions are dominant over the phase separation, the homogenization proceeds without a change in the domain size. The higher the extent of phase separation, the lower the increasing rate of the DR. However, when the phase separation is sufficiently dominant, the effect of the extent of phase separation on the increasing rate of the degree of randomness become less significant.     

Preparation and characterization of melt-spun PVC filament yarns

Polyvinyl chloride (PVC) fibers were melt-spun to prepare mono and multifilament yarns. To find optimum spinning and drawing conditions, various parameters such as spinning temperature, spinneret diameter, drawing temperature, and drawing ratio were examined. From the observation of the spinnability under various conditions, we found that the optimum conditions were as following: the extrusion temperature and die temperature were 175–180°C and 185–190°C, and the drawing temperature and drawing ratio were 85–95°C and 3.4, respectively. Under these conditions, the spinneret diameter could be reduced to the minimum value, 0.5 mm. Spun PVC filament yarns were subjected to the different yarn texturing process of stuffing box and pin false-twist method. The PVC yarn fabric was prepared by the knitting of textured yarns. Finally, the anion-emission and antibiotic properties of the knitted PVC fabrics were precisely evaluated.     

Early generation selection for important agronomic characteristics in a potato breeding population

Methods used by potato breeders to screen seedlings in early generations for agronomic characteristics are reviewed. Alternative strategies for maximizing response to selection are compared. Data are presented to demonstrate the effect of various selection methods and to aid in developing a selection philosophy. A moderate intensity of selection over several generations appears to best effect a balance between genetic advance and loss of valuable genotypes, while at the same time allowing for reasonably efficient operation.     

Shepody: A long,smooth, white-skinned potato of medium maturity with excellent French fry quality

Shepody is a long, smooth, white-skinned potato cultivar with excellent French frying quality and Kennebec maturity. It has good specific gravity and boils and bakes well.     

The effect of multi-walled carbon nanotubes on the molecular orientation of poly(vinyl alcohol) in drawn composite films

Poly(vinyl alcohol) (PVA)/multi-walled carbon nanotube (MWNT) composite films were prepared by casting a DMSO solution of PVA and MWNTs, whereby the MWNTs were dispersed by sonication. A significant improvement in the mechanical properties of the PVA drawn films was achieved by the addition of a small amount of MWNTs. The initial modulus and the tensile strength of the PVA drawn film increased by 30% and 45% respectively, with the addition of 1 wt% MWNTs, which are close to those calculated from the rule of mixtures, and were strongly dependent upon the orientation of the PVA matrix. The mechanical properties, however, were not improved with a further increase in the MWNT content. The orientation of MWNTs in the composite was not well developed compared to that of the PVA matrix. This result suggests that the improvement of the molecular orientation of the PVA matrix plays a major role in the increase of the mechanical properties of the drawn PVA/MWNT composite films.     

The correlation analysis between the appearance-related performances and the mechanical properties on lyocell-interlining bonded fabric

Lyocell is drawing attention as a new material, environmentally friendly fiber. Precedent researches on lyocell are mostly on structure, characteristics, physical properties, and dyeability. There are few researches on interlining for lyocell clothes production. This study analyzes the correlation between the appearance-related performances of lyocell-interlining bonded fabric and the mechanical properties of fusible interlining, lyocell face fabric, and lyocell-interlining bonded fabric. The stiffness of lyocell-interlining bonded fabric correlates with LT, WT, G, 2HG, 2HG5, B, 2HB, WC, and RC of fusible interlining; LT, EMT, G, 2HG, 2HB, RC, and T of lyocell face fabric; LT, WT, G, 2HG, 2HG5, B, 2HB, and T of lyocell-interlining bonded fabric. The drapability of lyocell-interlining bonded fabric correlates with LT, WT, G, 2HG, 2HG5, B, 2HG, WC, and RC of fusible interlining; LT, EMT, G, 2HG, 2HG5 and RC of lyocell face fabric; LT, EMT, G, 2HG, 2HG5, B, 2HB, LC, RC, and T of lyocell-interlining bonded fabric. The crease recovery of lyocell-interlining bonded fabric correlates with RT, T, W, WT, G, and 2HG of fusible interlining; LC, W, LT, EMT, G, 2HG, and 2HG5 of lyocell face fabric; WC, T, LT, G, 2HG, and 2HG5 of lyocell-interlining bonded fabric.     

Synthesis and thermal properties of polyhydroxyamide copolymer and its derivatives

We synthesized a polyhydroxyamide (PHA) copolymer via low-temperature solution polymerization of 3,3'-dihydroxybenzidine with terephthaloyl chloride (80.0 mol%) and isophthaloyl chloride (20.0 mol%) in N,Ndimethylacetamide with the aid of LiCl. We prepared the PHA copolymer derivatives containing the fluorine-based substituents and investigated their solubility, cyclization behavior, and thermal properties using a differential scanning calorimeter (DSC), a thermogravimetric analyzer (TGA), and the simultaneous thermogravimetric analyzer coupled with a mass spectrometer (STA-MS). The chemical structures of the PHA copolymer and its derivatives, as well as the polybenzoxazoles (PBOs) obtained through thermal cyclization of the copolymer and derivatives, were determined by a fourier transform infrared (FT-IR) spectroscopic analysis. The PHA copolymer could be dissolved in organic solvents only with the aid of LiCl, while its derivatives were readily soluble in DMA_c and NMP without LiCl at room temperature. The DSC and TGA results demonstrated that the PHA copolymer derivatives could be converted to PBOs at a lower temperature than the PHA copolymer.