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Summary  Two new bisphenol monomers containing naphthylene groups were synthesized by a Friedel-Crafts acylation reaction followed by a demethylation reaction. Four naphthylated poly(aryl ether ketone)s (PANEKs) were successfully prepared via a typical nucleophilic substitution polycondensation. These PANEKs exhibited excellent properties including high Tgs (above 204oC) and good thermal stability (the temperature at 5% weight loss in air was above 430oC). They had improved solubility, and flexible and transparent membranes could be cast from their solutions. The good mechanical property (tensile strength of 82.2∼102.8 MPa, Young’s moduli of 2.1∼2.4 GPa, and elongation at break of 17∼31%) indicated they were strong materials. Low dielectric constant (2.8-2.9 at 1 MHz) and moisture absorptions (i [ABSTRACT FROM AUTHOR]

Two novel hyperbranched poly (aryl ether)s with azobenzene moieties in both the main chain and side chain of the branched arms were prepared by using B3 + A2 methodology via a nucleophilic aromatic substitution polycondensation. Structures of the hyperbranched poly (aryl ether)s with azobenzene moieties (azo-HPAEs) were characterized by means of IR, UV-visible, 1H NMR spectroscopy, and XRD. It is shown that both the azo-HPAEs exhibit high glass transition temperatures (Tg), excellent thermal stability and homogeneous photochromic behavior. By exposing their spin-coating films to an interference pattern of laser beam, both the azo-HPAEs could be used for rapid (within 30 s) fabrication of surface-relief gratings (SRGs). The obtained SRGs present no shape changes even at temperatures up to 200 °C. Especially, the azo-HPAE with azobenzene moieties in the side chain shows larger photoinduced birefringence intensity and better reversible optical storage than the one with azobenzene moieties in the main chain upon irradiation with 532 nm Nd:YAG laser. The novel azo-PAEs are photoactive to UV light (355 nm), making them potentially useful for high density information storage. [ABSTRACT FROM AUTHOR]

As an emerging non-contact cold chain preservation technology, the impact of the DENBA+ on plant cell wall metabolism and its mechanism of inhibiting softening have not been addressed. In this study, strawberries were used as an experimental model to investigate the effect of space electric field storage on cell wall metabolism. Compared with the control, 500 V DENBA+ treatment was able to reduce the firmness loss of strawberries by 18.3 % on 18 d. Additionally, the DENBA+ exhibited a pronounced ability to suppress fruit softening enzyme (FaPG1 and FaβGal4) expression, delay the rise in polygalacturonates (PG), pectin methyl esterase (PME), cellulase (Cx), and β-galactosidase (β-Gal) activities, postpone the decline in cell wall matrix (CWM), insoluble solid pectin (ISP), and colloidal soluble pectin (CSP) content along with hemicellulose and cellulose levels while attenuating water-soluble pectin (WSP) accumulation during cold storage period. These findings contribute to the maintenance of fruit cell wall structural integrity with the aim of sustaining strawberry firmness and retarding the progression of aging. • DENBA+ delayed the degradation of strawberry cell walls. • DENBA+ inhibited the cell wall-modifying enzymes activities of strawberry. • DENBA+ keeps the strawberries from softening. • DENBA+ affected the expression levels of FAPG1，FaPME1 and FaβGAL4. [ABSTRACT FROM AUTHOR]

Abstract: An unidirectional ultra-high modulus M40J carbon fiber reinforced 5A06 aluminum alloy with volume fraction of 55% was fabricated by the pressure infiltration method. The effect of thermal cycling (−70 to 120°C and −196 to 120°C) on the mechanical properties of Cf/Al composites was investigated. Bending modulus increased abruptly after five thermal cycles and then reached a platform. However, after 50 cycles, the bending modulus decreased with the increase of cycles due to generation and propagation of microcracks at C fiber/Al interface. The bending strength of composites showed fluctuations between 800 and 1000MPa, and the amount and length of pull-out fiber increased with the increase of the thermal cycling times regardless of temperature difference. Microstructure observation revealed the formation of microcracks and interface debonding at the C fiber/Al interface after thermal cycling treatment, and the amount of the microcracks and interface debonding increased with the temperature difference. The main interfacial products in annealed Cf/Al composites were rod-like Al3Mg2 and bulky Al58Mg42, and no significant Al4C3 was observed at C fiber/Al interface. The thermal cycling treatment used in the present work had little effect on the interface microstructure of Cf/Al composites. Very few dislocations were observed in the Al matrix of annealed Cf/Al composites. However, the amount of dislocations in the Al matrix increased gradually with the increase of thermal cycles. Moreover, the amount of dislocations would decrease after a certain thermal cycles due to movement and annihilation of unlike-sign dislocations. [Copyright &y& Elsevier]

To effectively screen and characterize high sugar traits in sweet sorghum, we developed a sequence-characterized amplified regions (SCAR) marker, which had a 3.25 cM of linkage distance with the high sugar trait in sorghum. A total of 210 random primers was used to screen the polymorphism between a pair of parent lines, sweet sorghum LTR102 (as the female in this experiment), and common grain sorghum 654 (as the male), wherein 48 primers could produce at least one polymorphic fragment. The primer S3 36, which also produced a polymorphic fragment between the high sugar bulks and normal bulks of F5 progenies, was further analyzed. The genomic DNA of LTR102 was amplified by S336 to produce an 1119 bp of fragment. We sequenced this DNA, and synthesized a pair of SCAR primers (named as S3361119) specific to the DNA. The co-segregation between the SCAR marker and the high sugar trait was analyzed, and a 3.33% of recombinant rate was detected in F5 individuals, corresponding a 3.25 cM of linkage distance. This would provide an assistant means for sweet sorghum breeding. © 2014 Friends Science Publishers [ABSTRACT FROM AUTHOR]