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  • Author: J.-Z. Li, x
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Summary

Acetylated wood-silicate (AWS) composites and propionylated wood-silicate (PWS) composites were prepared and their dimensional stability and flame resistance evaluated. The results displayed that: (1) With the existing of silicate gels, the AWS and PWS composites showed lower values of bulking coefficient (B), antiswelling efficiency (ASE) during water and moisture absorptions, and moisture excluding efficiency (MEE) than the corresponding acetylated wood and propionylated woods, but the AWS and PWS composites still exhibited a fairly good dimensional stability. (2) The oxygen indexes (OIs) of the AWS and PWS composites were higher than those of untreated wood specimens, and increased with an increase in weight percent gain (WPGs) of silicate gel, endowing them with flame-resistance.

Abstract

The ion-exchange behavior of Zr and Hf in H2SO4 and H2SO4/HClO4 mixed solutions has been studied by a batch method using the carrier-free radiotracers 88Zr and 175Hf. It is found that the ion-exchange behavior of Zr and Hf is basically similar to each other, and that Zr and Hf are adsorbed on the cation-exchange resin as well as on an anion-exchange one in H2SO4. In 0.11−0.99 M H2SO4, the logarithmic values of distribution coefficients (K d) of Zr and Hf on the cation- and anion-exchange resins linearly decrease with log[H+]eq and log[HSO4 -]eq, respectively, indicating that M4+ and M(SO4)3 2- (M=Zr and Hf) are the predominant cationic and anionic species adsorbed on the resins, respectively. The K d values of Zr and Hf on the cation-exchange resin in H2SO4/HClO4 at [H+]eq=1.0 M also decrease with an increase of [HSO4 -]eq, reflecting successive formation of sulfate complexes. The slope analysis demonstrates that Zr and Hf are coordinated by one SO4 2- ion at 0.011 and 0.020 M [HSO4 -]eq, respectively, and by two SO4 2- ions at 0.079 and 0.20 M [HSO4 -]eq, respectively.

Abstract

Induction of 2n pollen is a required technique for cultivating polyploid via sexual polyploidy. Orthogonal design or Taguchi Design was applied to select the best treatment process of 2n pollen induction in Populus × popularis from different levels of the meiosis stage of male flower buds, colchicine concentration, times of injection, and interval between injections. Flow cytometry and chromosome counting were used to identify the triploids from the offspring of P. × euramericana. (Dode) Guinier pollinated with induced pollen of P. × popularis. The results showed that high 2n pollen rate can be achieved by selecting the flower buds during diakinesis stage in meiosis, and then injecting 0.6% colchicine 4 times with 2 hours interval. The 2n pollen rate reached 62.10% by this process, and two triploids were obtained, which indicates that it is possible for cultivating triploids via 2n pollen induction by colchicine treatment in poplar. Results and protocol related to 2n pollen induction, polyploid identification and effect of 2n pollen in this study might be applicable in polyploidy breeding in section Aigeiros and Tacamahaca of poplar.

Summary

The diagnosis of trichinellosis is rather difficult because fever, myalgia and eosinophilia are nonspecific, and diagnosis may be delayed. We describe a small familiar outbreak of trichinellosis occurred in early 2009 in Tibet, southwestern China, due to consumption of raw pork. The patients with trichinellosis were diagnosed by muscle biopsy and serological tests (ELISA and IFA) early at 12 days after onset of disease. Both of the pre-encapsulated and encapsulated Trichinella larvae collected from biopsy muscles and residual pork were identified as Trichinella spiralis by multiplex PCR. This is the first species identification of Trichinella isolates from the biopsy muscles of patients with trichinellosis in China.