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Ditemukan 9 dokumen yang sesuai dengan query
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Sergio
"Salah satu upaya yang dapat dilakukan untuk mengembangan material maju adalah penggunaan kawat superkonduktor sebagai material dasar untuk banyak aplikasi di dunia kedokteran. Magnesium diborida MgB2 adalah salah satu kawat superkonduktor yang memiliki potensi besar untuk dipakai sebagai pengganti kawat superkonduktor tipe Nb. Superkonduktor MgB2 memiliki temperatur kritis yang relative tinggi high temperature superconductor, HTS. Masalah yang timbul dalam proses pembuatan kawat superkonduktor MgB2 adalah terbentuknya retak pada permukaan. Pembentukan retak permukaan ini harus dicegah karena akanmenggangu nilai superkonduktifitasnya. Beberapa upaya telah dilakukan untuk mencegah terbentuknya retak permukaan, antara lain penggunaan Fe tube. Meskipun temperatur kritis dari MgB2 sudah lebih tinggi dari superkonduktor tipe Nb, namun ternyata temperatur kritis dari MgB2 masih dapat ditingkatkan, diantara lain menggunakan dopan. Dalam penelitian ini, dopan nano-SiC digunakan untuk meningkatkan temperatur kritis dari MgB2. Dalam penelitian ini, metoda in-situ Powder in Tube PIT digunakan untuk membuat kawat superkonduktor. Proses ini dilanjutkan dengan proses perlakuan panas pada lingkungan gas Argon. Setelah kawat superkonduktor dibuat, akan dilakukan analisis karakterisasinya dengan memakai XRD, SEM dan pengukuran resistivity untuk mengetahui sifat superkonduktivitas kawat tersebut. Untuk hasilnya, ditemukan beberapa senyawa yang tidak diinginkan seperti MgO, Mg2Si dan Si whiskers. Ini disebabkan karena berbagai faktor seperti kurangnya panas ataupun keadaan lingkungan tidak vakum.

One of the attempts performed to improve advanced materials is the application of superconducting wires as base materials for medical application. Magnesium Diboride MgB2 is one of the most promising superconducting wires that can be used to replace superconducting wires Nb. MgB2 superconductor has relatively high critical temperature, however, the main problem in manufacturing MgB2 superconducting wires is the formation of crack at the surface. This crack formation should be avoided, because crack will weaken the superconductivity of a material. There are several ways to avoid the formation of crack, which include the usage of Fe tube. The critical temperature of pure MgB2 is higher than Nb group superconductor, and this critical temperature of MgB2 still can be enhanced by several methods such like doping. Recently, it was found that doping of SiC can make the critical temperature of MgB2 superconductor enhanced. In this research, Powder in Tube PIT were used. These powders were then poured into the Fe tubes with heat treatment under an argon environment. These samples were then characterized by using X Ray Diffraction XRD , Scanning Electron Microscopy SEM and resistivity testing under TC. The results show that nano SiC can be a very high potential doping agent for MgB2 superconducting wires, however, further sample preparation should be considered in manufacturing MgB2 wires. This is true since the unexpected phases such like MgO and Mg2Si exist in the phase. Applying heat treatment to MgB2 can causes instability in MgB2, and thus having all sample prepared under vacuum is recommended. There is also a chance for the boron inside the MgB2 can also doped inside the SiC, especially for nano SiC which have high surface area. Hence, liquid phase sintering would likely to be recommended, due to dissolving of boron into molten magnesium.
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Depok: Fakultas Teknik Universitas Indonesia, 2017
S67657
UI - Skripsi Membership  Universitas Indonesia Library
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Franco, Sergio
Boston: McGraw-Hill , 2002
621.381 5 FRA d
Buku Teks  Universitas Indonesia Library
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Zyman, Sergio
New York: Harper Business, 2000
658.8 ZYM e;658.8 ZYM m (1)
Buku Teks SO  Universitas Indonesia Library
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Zyman, Sergio
Hoboken, N.J.: John Wiley & Sons, 2002
659.1 ZYM e
Buku Teks SO  Universitas Indonesia Library
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Franco, Sergio
Boston: McGraw-Hill, 1998
621.381 5 FRA d
Buku Teks  Universitas Indonesia Library
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Benedetto, Sergio
New York: Kluwer Academic, 1999
621.382 BEN p
Buku Teks  Universitas Indonesia Library
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Franco, Sergio
Boston: McGraw-Hill , 2015
621.381 5 FRA d
Buku Teks  Universitas Indonesia Library
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Velastin, Sergio A. author
"Conventional video surveillance, where people sit in front of banks of TV monitors may soon become obsolete as key enabling technologies develop. This book details recent developments in machine vision algorithms capable of handling complex visual data acquired by camera systems. It also explores advances in distributed computing and distributed intelligence systems, capable of handling numerous devices and adapting to the evolution of the complex communication networks, thereby inferring a better interpretation of the dynamics of people and objects."
London: Institution of Engineering and Technology, 2008
e20452602
eBooks  Universitas Indonesia Library
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Chavez, Sergio
"Based on observations and in-depth interviews, Border Lives tells the story of how diverse groups of individuals came to establish roots in Tijuana, beginning shortly after the termination of the Bracero Program (1942-64) and ending in the present. It describes how these different groups of migrants and residents adapt to a dynamic borderlands economy and draw on the border as a resource to construct their livelihoods. The book details the consequences of border-enforcement and immigration restrictions over several decades, documenting the ways in which policies create precarious situations for those who cross the border and come in contact with them on a regular basis. The book shows how individuals have used the border as a resource in the past, and how current residents are forced to seek ways to access the opportunities that the border offers in the future. Yet for all of these border crossers-former, current, and future-the border itself figures significantly, not only in their livelihood strategy but also in their lifestyle, shaping their knowledge, action, and their relationships, controlling their time, and allowing them to convert US wages into a Mexican standard of living, without losing the social and cultural comforts of Tijuana-as-home."
Oxford: Oxford University Press, 2016
e20470411
eBooks  Universitas Indonesia Library