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"Kondisi lingkungan dapat memberikan efek yang sangat besar dalam bentuk kegagalan komposit karbon/epoksi. Kondisi lingkungan menjadi perhatian dalam dunia penerbangan karena dapat mempengaruhi kekuatan mekanik dan sifat termal dari material yang dijadikan bahan penyusun struktur pesawat. Penelitian ini dilakukan untuk mengetahui pengaruh kondisi lingkungan, khususnya kemampuan penyerapan kadar air, kekuatan mekanik, sifat termal, dan jenis kerusakan dari komposit karbon/epoksi unidirectional. Komposit ini dibuat dengan metode dry hand lay-up. Untuk mengetahui hal tersebut, komposit karbon diberikan kondisi lingkungan yang berbeda, yaitu keadaan tanpa perendaman, direndam dalam air panas, dan air laut dalam waktu tertentu. Dari hasil pengamatan penyerapan kadar air dari, didapatkan kandungan kadar air maksimum yang terserap ke dalam komposit karbon/epoksi dalam lingkungan air panas 0,89 selama 1100 jam dan air laut 0,57 selama 1200 jam perendaman. Uji mekanik short-beam shear menunjukkan persentase penurunan nilai kekuatan antarlamina dari hasil uji mekanik pada keadaan air panas dan air laut berturut-turut sebesar 9,66 dan 0,92 dibandingkan dengan bahan tanpa perendaman. Suhu transisi gelas relatif sama dari tiap kondisi lingkungan. Hasil pengamatan mikroskop optik dan Scanning Electron Microscope tidak memperlihatkan perbedaan yang berarti dari ketiga komposit. Jadi material komposit karbon/epoksi unidirectional tidak mengalami perubahan berarti pada sifat termal dan kerusakan permukaan akibat pengaruh air panas dan air laut.

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Environmental conditions can result a profound effect in a forms of carbon epoxy composite failures. Environmental conditions are one of the main considerations in the aerospace industry as they can affect the mechanical strength and thermal properties of the materials that be used as aircraft structures. This study was aimed to determine the effect of environmental conditions, especially the moisture absorption, mechanical strength, thermal properties, and types of damage of unidirectional carbon epoxy composites. The composites were fabricated by a dry hand lay up process. The composites were conditioned in different environment which were normal condition or without immersion, soaked in both hot water, and seawater within a certain time. The maximum moisture content that was absorbed in the composites was 0.89 for 1100 hours in hot water and was 0.57 in seawater for 1200 hours of immersion. Furthermore, short beam shear test results showed that the interlaminate strength values reduced 9.66 and 0.92 in hot water and sea water conditions respectively compared to composites in normal condition. The glass transition temperature of hot water and sea water conditioned materials were relatively similar compared to materials in normal condition. According to optical microscope and Scanning Electron Microscope observations, there was no visible difference on the surface of three materials. Thus, the thermal property and the appearance of the unidirectional carbon epoxy composites did not change in hot water and sea water."

"Natural fiber-reinforced composites have the potential to replace synthetic composites, leading to less expensive, stronger and more environmentally-friendly materials. This book provides a detailed review on how a broad range of biofibers can be used as reinforcements in composites and assesses their overall performance.The book is divided into five major parts according to the origins of the different biofibers. Part I contains chapters on bast fibers, part II leaf fibers, part III seed fibers, part IV grass, reed and cane fibers, and finally part V covers wood, cellulosic and other fibers including cellulosic nanofibers. Each chapter reviews a specific type of biofiber providing detailed information on the sources of each fiber, their cultivation, how to process and prepare them, and how to integrate them into composite materials. The chapters outline current and potential applications for each fiber and discuss their main strengths and weaknesses."

"Dewasa ini penggunaan material komposit serat karbon mulai banyak digunakan dalam berbagai sektor industri karena memiliki sifat-sifat yang mampu memenuhi tuntutan teknologi, seperti ringan, tahan fatik, dan tahan terhadap temperatur tinggi. Penelitian terhadap perfoma komposit serat karbon baik termal dan mekanik masih jarang dilakukan. Oleh karena itu dilakukanlah pengujian untuk mengetahui hal tersebut. Komposit serat karbon yang digunakan memiliki variasi densitas berbeda yaitu 200 dan 240 gr/m2Metode yang digunakan dalam penelitian ini berbasis pada kalorimeter kerucut. Pembakaran dilakukan pada nilai fluks kalor maksimum 23,61 kW/m2 dan minimum 14,15 kW/m2. Pada penelitian ini juga dilakukan pengujian tarik dan SEM untuk mengetahui sifat mekanik dari komposit serat karbon. Hasil dari penelitian ini menunjukkan semakin tinggi fluks kalor, maka laju produksi kalor dari pembakaran komposit serat karbon juga meningkat dimana laju produksi maksimum yang dicapai bernilai 160-170 kW/m2. Sementara itu dari pengujian mekanik didapatkan bahwa material komposit serat karbon memiliki sifat diantara ulet dan getas.

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In this present days, the use of carbon fiber composite material used widely in various industrial sectors. This happens because carbon fiber composite have good properties that can fulfill the demands of technology requirements, such as lightweight, fatigue resistant, and withstand to high temperatures. Studies on carbon fiber composites performance, especially regarding its thermal and mechanical performance, are still not observed widely. Carbon fiber composites used in this study has density of 200 and 240 gr/m2.

The method used in this study based on cone calorimeter. Combustion was performed onthe maximum heat flux of 23.61 kW/m2 and a minimum heat flux of 14.15 kW/m2. This study also used the tensile test and SEM analysis to determine the mechanical properties of carbon fiber composites.

The results of this study showed that at the higher heat flux, the heat release rate (HRR) carbon fiber composites was increased withthe maximum valueof 160-170 kW/m2. Meanwhile, analysis of mechanical properties showed that the carbon fiber composite material has a characteristic between ductile and brittle."

"Penelitian ini bertujuan untuk mengetahui kekuatan rekat geser resin komposit serat sebagai substuktur dengan resin komposit partikulat berbeda komposisi. Resin komposit partikulat G-aenial posterior Kelompok A, 10 spesimen dan Tetric N-ceram Kelompok B,10 spesimen digunakan sebagai lapisan atas resin komposit serat EverX Posterior. Uji kuat rekat geser dilakukan menggunakan UTM dengan beban 100 kgf dan crosshead-speed 0.5 mm/menit. Data dianalisis menggunakan uji statistik independent sample t test. Hasil penelitian menunjukan nilai rerata kuat rekat geser yakni 18,64 1.5 MPa A dan 22,05 1,8 MPa B . Disimpulkan bahwa terdapat perbedaan kuat rekat geser yang bermakna pada kedua kelompok.

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The aim of this study was to identify shear bond strength fiber reinforced composite as a substructure with different composition of particulate filled composite. Particulate filled composite G aenial posterior Groups A, 10 specimen and Tetric N ceram Groups B, 10 specimen used as an upper layer of FRC EverX Posterior. Shear bond strength test was performed using UTM with a load of 100 kgf and crosshead speed of 0.5 mm min. Data were analyzed using statistical test independent sample t test. The result of this study showed the mean shear bond strength values are 18,64 1.5 MPa A and 22,05 1,8 MPa B . It was concluded that there is a significance difference of shear bond strength between two groups."

"Pengangkutan ikan hasil tangkapan nelayan tradisional merupakan hal penting setelah penangkapan ikan. Penggunaan wadah angkut ikan merupakan salah satu upaya menjaga kualitas ikan. Selama ini pemanfaatan wadah angkut ikan masih kurang efektif dan efisien sehingga terjadi kerugian karena kualitas dan nilai jual ikan rendah. Penelitian ini difokuskan pada kajian rancang bangun wadah angkut yang mudah dipindahkan dan ramah lingkungan agar ikan bernilai jual tinggi. Wadah dirancang untuk ikan hidup yang diperlengkapi sirkulasi air dan udara serta penyaringan kotoran sehingga salinasi dan pH air terkendali. Bahan wadah terbuat dari material komposit berpenguat serat pisang abaca. Komposit dibentuk menjadi anyaman tenunan dan anyaman tikar. Dari hasil pengujian tarik diperoleh kekuatan tarik rata - rata sebesar 9 MPa dan tegangan luluh rata - rata sebesar 6,538 MPa. Sedangkan hasil perhitungan pembebanan pelat diperoleh tebal komposit minimum sebelum terjadi defleksi 3 mm yaitu 3,27 mm.

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Transportation of fish catches is an important traditional fishing after catching a fish. The use of container transport fish is one of the efforts to maintain the quality of fish. During this time fish transport container utilization is still less effective and efficient so that there is a loss because of the quality and value of fish sold low. This study focused on the study design of container transport is easily removable and friendly environment for high value fish. Containers designed for live fish equipped air circulation and filtration of water and dirt so that the salinization and water pH control. Material container made of composite materials berpenguat abaca fiber. Composite formed into woven fabrics and woven mats. From the results obtained by tensile testing tensile strength - average of 9 MPa and yield stress - average of 6.538 MPa. While the calculation results obtained by the imposition of a thick composite plate minimum before the deflection of 3 mm is 3.27 mm."

"Kebutuhan material semikonduktor untuk industri elektronika di Indonesia semakin meningkat ditandai dengan tren sumbangan dari industri elektronika terhadap ekspor industri yang terus meningkat setiap tahunnya. Namun demikian, ternyata Indonesia masih mengimpor bahan baku material semikonduktor. Permasalahan lain dari penggunaan material semikonduktor adalah komponen semikonduktor yang tidak dipergunakan lagi akan dibuang menjadi sampah plastik yang sulit diuraikan. Oleh karena itu pembuatan material semikonduktor yang berasal dari bahan alam dapat menjadi solusi dari permasalahan tersebut. Salah satu material yang dapat digunakan untuk material semikonduktor adalah komposit serat nata de coco dengan filler silika. Metode yang digunakan untuk membuat komposit serat nata de coco dengan filler silika adalah metode perendaman dengan variasi ukuran partikel silika, konsentrasi suspensi silika, dan lama perendaman. Dari hasil SEM-EDX dapat diketahui bahwa silika telah terdeposisi pada serat. Hasil uji konduktivitas listrik menunjukkan bahwa semua komposit yang dihasilkan bersifat semikonduktor. Nilai konduktivitas tertinggi sebesar 1,21 x 10-5 S/cm atau kurang lebih 48 kali konduktivitas serat nata de coco polos dihasilkan dari komposit serat nata de coco/silika dengan ukuran partikel 370 nm, konsentrasi suspensi 6%w/v, dan lama perendaman 3 hari.

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The needs of semiconductor material for the electronic industry in Indonesia is increasing each year according to the postive trend of export from electronic industry in Indonesia. In contrast, the fact that Indonesia actually still import the raw material for the semiconductor material that is used in electronic industry is ironic. Another problem comes from the use of semiconductor material is that the unused semiconductor component can be a plastic waste that needs a long time to be degraded. As a solution for this condition, the making of semiconductor material from natural substances is needed. One of the natural substances that can be used as the semiconductor material is nata de coco fiber composite with silica filler. The submerged method is used in the production of nata de coco fiber composite with silica filler by using the immersion time, concentration of nanosilica suspension, and the size of silica particle as the variations. From the SEM-EDX results, it can be seen that silica particle is deposited on the nata de coco fiber. From the conductivity characterization, it is known that all of the composite can be categorized as semiconductor material. The highest electric conductivity, 1,21 x 10-5 S/cm or about 48 times higher than the conductivity of nata de coco fiber, is reached from the nata de coco fiber composite with silica filler that has a particle diameter of 370 nm, and submerged in silica suspension with concentration 6% w/v for 3 days."

"Penelitian ini bertujuan untuk menganalisis pengaruh jarak penyinaran terhadap depth of cure DOC resin komposit serat sebagai substruktur. Delapan belas spesimen EverX Posterior warna A3 berbentuk silinder diameter 6 mm dan tebal 4 mm dibagi menjadi 3 kelompok jarak penyinaran 0, 2, dan 4 mm yang dipolimerisasi dengan LED Litex 695, irradiansi 800 mW/cm2, selama 20 detik. Pengukuran DOC dilakukan melalui rasio kekerasan Vickers. Analisis data dilakukan menggunakan uji ANOVA satu arah. Hasil penelitian menunjukkan DOC pada jarak penyinaran 0, 2, dan 4 mm sebesar 79 0,7, 77 0,6, dan 75 0,8. Disimpulkan terdapat perbedaan bermakna pada nilai DOC pada seluruh jarak penyinaran.

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This study aims to analyze the effect of light curing distance on the depth of cure DOC of fiber reinforced composite as substructure. Eighteen specimens consist of EverX Posterior shade A3, formed into a cylindrical shape 6 mm in diameter and 4 mm thickness divided into 3 groups according to light curing distance 0, 2, and 4 mm which were polymerized with LED Litex 695, irradiance 800 mW cm2, for 20s. Meansurement of DOC was carried out by Vickers hardness ratio of specimens. Data were analyzed statistically by one way ANOVA test. The result showed the DOC at a light curing distances of 0, 2, and 4 mm was 79 0,7, 77 0,6, and 75 0,8. It was concluded that there is a significant difference in DOC among the light curing distance."

"Materials science and engineering of carbon, fundamentals provides a comprehensive introduction to carbon, the fourth most abundant element in the universe. The contents are organized into two main parts. Following a brief introduction on the history of carbon materials, Part 1 focuses on the fundamental science on the preparation and characterization of various carbon materials, and Part 2 concentrates on their engineering and applications, including hot areas like energy storage and environmental remediation. The book also includes up-to-date advanced information on such newer carbon-based materials as carbon nanotubes and nanofibers, fullerenes and graphenes."