Researches on novel natural fibers in polymer-based composites will help promote the invention of novel reinforcement and expand their possible applications.Herein,in this study,novel cellulosic fibers were extracted ...Researches on novel natural fibers in polymer-based composites will help promote the invention of novel reinforcement and expand their possible applications.Herein,in this study,novel cellulosic fibers were extracted from the stem of manau rattan(Calamus manan)by mechanical separation.The chemical,thermal,mechanical and morphological properties of manau rattan fibers were comprehensively analyzed and studied by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)analysis,thermogravimetric analysis(TGA),single fiber tensile test and scanning electron microscopy(SEM).Component analysis re-sults showed that the cellulose,hemicellulose and lignin contents of C.manan fibers were 42wt%,20wt%,and 27wt%,respectively.The surface of the rattan fiber was hydrophilic according to the oxygen/carbon ratio of 0.49.The C.manan has a crystalline index of 48.28%,inducing a max-imum degradation temperature of 332.8°C.This reveals that it can be used as a reinforcement for thermoplastic composites whose operating temperature is below 300°C.The average ten-sile strength can reach(273.28±52.88)MPa,which is beneficial to improve the mechanical properties of rattan fiber reinforced composites.The SEM images displayed the rough surface of the fiber,which helped to enhance the interfacial adhesion between the fibers and matrices in composites.These results indicate the great potential of C.manan fibers as the reinforcement in polymer-based composites.展开更多
The Manaus Free Trade Area （ZFM） will end in 2023, but there is a proposal to amend the Brazilian Federal Constitution so that it lasts until 2073. From the understanding of discourse as a social practice, this pape...The Manaus Free Trade Area （ZFM） will end in 2023, but there is a proposal to amend the Brazilian Federal Constitution so that it lasts until 2073. From the understanding of discourse as a social practice, this paper is based on the analysis of 265 parliamentary pronouncements, 19 numbers of an institutional magazine, and 626 news texts from the most important local newspaper, all published between 2007 and 2010. It reveals a shift in the discourse about the ZFM, guided by ecological modernization. The industries are now presented as responsible for preserving the rainforest： it is said that if the tax incentives stop, there will be unemployment and deforestation. This tragic story line does not recognize the role of traditional peoples and communities in forest conservation and neither is open to the public debate about other models of development for the Amazon.展开更多
Here in the most unlikely of places, in the city of Manaus, at the heart of the Amazon rainforest, stands this grand building-the Teatro Amazonas, or the Amazon Theatre and Opera House. The end of the 19th century was...Here in the most unlikely of places, in the city of Manaus, at the heart of the Amazon rainforest, stands this grand building-the Teatro Amazonas, or the Amazon Theatre and Opera House. The end of the 19th century was a boom time for the Amazonian region of Brazil. It was 1)flush with money from exports from its large 2)rubber 3)plantations. Manaus quickly became one of Brazil's richest cities. And this Opera House was to be the jewel in the jungle.展开更多
基金support by National Natural Science Foundation of China(No.51803093)Natural Science Foundation of Jiangsu Province(No.BK20180770).
文摘Researches on novel natural fibers in polymer-based composites will help promote the invention of novel reinforcement and expand their possible applications.Herein,in this study,novel cellulosic fibers were extracted from the stem of manau rattan(Calamus manan)by mechanical separation.The chemical,thermal,mechanical and morphological properties of manau rattan fibers were comprehensively analyzed and studied by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)analysis,thermogravimetric analysis(TGA),single fiber tensile test and scanning electron microscopy(SEM).Component analysis re-sults showed that the cellulose,hemicellulose and lignin contents of C.manan fibers were 42wt%,20wt%,and 27wt%,respectively.The surface of the rattan fiber was hydrophilic according to the oxygen/carbon ratio of 0.49.The C.manan has a crystalline index of 48.28%,inducing a max-imum degradation temperature of 332.8°C.This reveals that it can be used as a reinforcement for thermoplastic composites whose operating temperature is below 300°C.The average ten-sile strength can reach(273.28±52.88)MPa,which is beneficial to improve the mechanical properties of rattan fiber reinforced composites.The SEM images displayed the rough surface of the fiber,which helped to enhance the interfacial adhesion between the fibers and matrices in composites.These results indicate the great potential of C.manan fibers as the reinforcement in polymer-based composites.
文摘The Manaus Free Trade Area （ZFM） will end in 2023, but there is a proposal to amend the Brazilian Federal Constitution so that it lasts until 2073. From the understanding of discourse as a social practice, this paper is based on the analysis of 265 parliamentary pronouncements, 19 numbers of an institutional magazine, and 626 news texts from the most important local newspaper, all published between 2007 and 2010. It reveals a shift in the discourse about the ZFM, guided by ecological modernization. The industries are now presented as responsible for preserving the rainforest： it is said that if the tax incentives stop, there will be unemployment and deforestation. This tragic story line does not recognize the role of traditional peoples and communities in forest conservation and neither is open to the public debate about other models of development for the Amazon.
文摘Here in the most unlikely of places, in the city of Manaus, at the heart of the Amazon rainforest, stands this grand building-the Teatro Amazonas, or the Amazon Theatre and Opera House. The end of the 19th century was a boom time for the Amazonian region of Brazil. It was 1)flush with money from exports from its large 2)rubber 3)plantations. Manaus quickly became one of Brazil's richest cities. And this Opera House was to be the jewel in the jungle.
