All rights reserved.”
“A series of core-shell type cationic soap-free latex were prepared by using styrene(St), butyl acrylate(BA), and methyl methacrylate(MMA) as main materials and introducing rosin as the functional monomer. Cationic
starch (CS-8), which has low relative viscosity, was used as the emulsifier and dispersant. The influencing factors of the reaction were studied and the optimal conditions were achieved. Then the products were characterized by scanning electron microscope (SEM), FT-IR, laser particle sizer, and particle charge detector (PCD). The results showed that the excellent performance and good sizing effects of SAE were achieved when the reaction conditions were as follows: the starch amount was 8 wt %, the charge Selleckchem MK2206 of the initiator (APS) was 0.5%, and the amount of rosin was 2 wt %. Under these conditions, the particle size of the latex was around 100 nm and had a narrow distribution, and the charge density of latex was 0.61 mmol L(-1). The water-resistant performance of paper was improved significantly when SAE was modified with rosin, and the Cobb value decreased by 46.8% compared to that of the paper sized by SAE without rosin. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 611-616, Selleck Screening Library 2012″
“Because of ever-increasing environmental deterioration
it is likely that the influx of UV-B radiation (280-320 nm) will increase as a result of the depletion of stratospheric ozone. Given this fact it is essential that we better understand both the rapid and the adaptive responses of plants to UV-B stress. Here, we compare the metabolic responses of wild-type Arabidopsis with that of mutants impaired in flavonoid LY3023414 (transparent testa 4, tt4; transparent testa 5, tt5) or sinapoyl-malate (sinapoylglucose accumulator 1, sng1) biosynthesis, exposed to a short 24-h or a longer 96-h exposure to this photo-oxidative stress. In control experiments we subjected the genotypes to long-day conditions as well as to 24- and 96-h treatments of continuous light. Following
these treatments we evaluated the dynamic response of metabolites including flavonoids, sinapoyl-malate precursors and ascorbate, which are well known to play a role in cellular protection from UV-B stress, as well as a broader range of primary metabolites, in an attempt to more fully comprehend the metabolic shift following the cellular perception of this stress. Our data reveals that short-term responses occur only at the level of primary metabolites, suggesting that these effectively prime the cell to facilitate the later production of UV-B-absorbing secondary metabolites. The combined results of these studies together with transcript profiles using samples irradiated by 24-h UV-B light are discussed in the context of current models concerning the metabolic response of plants to the stress imposed by excessive UV-B irradiation.