Judul: Karboksimetilasi Selulosa Mikrofibril Guna Meningkatkan Sifat Termal dan Mekanik Komposit Poliasam Laktat
Abstrak: Composite of polylactic acid (PLA) reinforced with microfibrillated cellulose (MFC) could replace petroleum-based plastics for automotives and electronics purposes. Unfortunately, the hydrophilicity of nanofibers make it difficult to attain good dispersion in a hydrophobic PLA matrix. Therefore, MFC was modified to carboxymethyl-MFC (CM-MFC) with DS 0.1 and 0.4 to enhance dispersion of nanofibers in a PLA matrix, thus improve the thermal and mechanical properties of the PLA composite. CM-MFC with DS 0.1 and 0.4 were obtained under reaction conditions of water and isopropanol (1:1 and 0:1). PLA composites were prepared using organic solvent, followed by kneading and hot pressing. The thermal and mechanical properties of PLA composites showed that the carboxymethylated MFC in the solvent accelerated the crystallization of PLA and improved the modulus of elasticity, tensile strength, and maximum strain by 0.4 GPa, 9 MPa, and 1%, respectively, at a fiber content of 10 (b/b)%. Based on these information, the dispersion and properties of PLA/MFC composites were enhanced using carboxymethylation at DS 0.1.
Keyword: PLA composite, carboxymethylation

Judul: Perbaikan Sifat Termal dan Mekanik Komposit Poliasam Laktat- Nanoselulosa melalui Asetilasi
Abstrak: Microfibrillated cellulose (MFC) has nano-sized dimension, high molecular weight, and high crystallinity that can be used as reinforcement and filler in polylactic acid (PLA) composites. Property differences between hydrophobic PLA and hydrophilic MFC cause low compatibility and dispersibility will decrease the thermal and mechanical properties of the PLA composites. Therefore, improvement of these properties should be done by modifying the MFC to MFCacetate. Degree of substitution (DS) of the MFC-acetate tested in the PLA composites were 0.2, 0.5, and 0.8. The success of acetylation was evidenced by infrared spectrophotometer: reduced absorption of -OH group at 3300 cm-1, existence of C=O stretching at 1770 cm-1 and C-O acetyl at 1235 cm-1. Compatibility and dispersibility in the composite was achieved by increasing the DS of acetyl. The best thermal and mechanical properties was achieved by DS 0.5 with high heat resistance, low crystalization temperature (Tcc), and melting temperature (Tm), namely 88 °C and 166 °C, respectively. Mechanical properties of the resulting DS 0.5 showed higher maximum strain, tensile strength, and modulus of elasticity as compared to the pure PLA and PLA/MFC composite by 1.6%, 31.3 MPa, and 2.7 GPa, respectively.
Keyword: polylactic acid, MFC-acetate, microfibrillated cellulose, cellulose acetate

Judul: Ragam jenis ektoparasit burung tekukur (Streptopelia chinensis) dan burung puter (Streptopelia bitorquata) di penangkaran
Abstrak: Spotted dove and Javan turtle dove are the bird species that are easily raised in captivity. Nevertheless, good management is required to successfully breed and raise the birds in captivity; otherwise, the condition may endanger the sustainability of the two bird species. Information on ectoparasites on the bodies of this bird as well as their captivity breeding has not been available, although admittedly taking ectoparasites from these bird families has much been done so that a research is obviously needed. This study aimed to find out various kinds of Spotted dove and Javan turtle dove ectoparasites and to learn various kinds of parasitic insects around the Spotted dove and Javan turtle dove cages. The study was conducted from April to June 2010. The methods of data collection included the general condition of the location, collection of ectoparasites specimens, processing and specimens identification. The data analysis was done descriptively and tabulated with the degree of infestation. The kinds of ectoparasites from the class of insects found in the body of Spotted dove were Goniocotes sp. and Columbicola columbae of phthiraptera order and Pseudolynchia canariensis of diptera order, and arachnida class, that is, tungau from the pterolichidae family. In terms of ectoparasites, Spotted dove and Javan turtle dove were similar, except that Javan turtle dove had no Pseudolynchia canariensis. Goniocotes sp. and Columbicola columbae were mallopaga order (biting lice) and were obligate. The kinds of parasitic insects in the vicinity of Spotted dove and Javan turtle dove cages were from the Ordo Diptera. The diptera classified as parasites included Anopheles, Culex, Psychodidae, Culicoides and Simulium, most of them vectors of disease. The presence of ectoparasites was closely related to how a breeding place is managed.
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