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"Combustion synthesis, or more specifically self-propagating high temperature synthesis, is an efficient manufacturing process that is used for a variety of advanced materials including powders, near-net shape products and functionally graded materials. This project investigated the combustion synthesis of one nonstoichiometric titanium carbide system with the aim to produce high surface-area porous materials. The system investigated was the (1+x)Ti + C system where x = 1.4, x = 1.6 and x = 1.7 and were successful SHS reactions. The combusted samples produced from the x = 1.4 system were qualitatively analysed with Scanning Electron Microscopy, showing porosity variation in the distance from the ignition point. X-Ray Powder Diffraction was performed on one of the samples and shows similar composition yet differing crystal structures to some comparable TiCx compounds. Velocity Profiles were taken to determine that the reaction wavefront begins in the middle of the sample and after ignition travels more rapidly on the outside. 500W of power is required to heat the Tungsten filament to the temperature required to initiate propagation of the reaction. The x = 1.6 and x = 1.7 velocity profiles were analysed and it was concluded that the x = 1.6 reaction wavefront is faster than the x = 1.7 reaction wavefront."

"Material Bi-Sr-Ca-Cu-O atau BSCCO dapat berperan sebagai superkonduktor suhu tinggi atau high temperature superconductor (HTS) dengan suhu kritis berkisar 80-110 K yang termasuk ke dalam jenis superkonduktor berbasis kuprat. Terdapat 3 fasa berbeda dalam menentukan superkonduktor suhu tinggi untuk material dengan rumus kimia umum Bi2Sr2Can−1CunO2n+4+x ini. Pembagiannya bergantung kepada jumlah atom kuprat penyusunnya, yaitu Bi2Sr2CuO (Bi-2201, n = 1), Bi2Sr2CaCu2O (Bi-2212, n = 2), dan Bi2Sr2Ca2Cu3O (Bi-2223, n = 3). Sejak pertama kali ditemukan pada tahun 1998 sampai saat ini, telah banyak penelitian terkait fabrikasi BSCCO dengan berbagai macam metode dan penambahan unsur lain dengan tujuan mengetahui pengaruhnya terhadap sifat fisik dan kelistrikannya. Pada penelitian ini, penulis melakukan percobaan terkait fabrikasi material BSCCO dengan penambahan unsur Titanium (TiO2). Terdapat empat buah sampel yang terbentuk, dengan fasa Bi-2212 yang lebih dominan dan stabil terbentuk. Adapun morfologi dan pesebaran daripada masing-masing unsur ditunjukkan dengan pengujian SEM dan EDS Mapping. Untuk mengetahui superkonduktivitas, termasuk suhu kritis (Tc), dari masing-masing sampel maka dilakukan uji superkonduktivitas dengan alat cryogenic magnetometer.

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Bi-Sr-Ca-Cu-O or BSCCO material can act as a high temperature superconductor (HTS) with a critical temperature of 80-110 K which is cuprates-based superconductor type. There are 3 different phases in determining the superconducting high temperature for BSCCO material with general chemical formula of Bi2Sr2Can−1CunO2n+4+x. To determine each phase has different number of constituent cuprates atoms, namely Bi2Sr2CuO (Bi-2201, n = 1), Bi2Sr2CaCu2O (Bi-2212, n = 2), and Bi2Sr2Ca2Cu3O (Bi-2223, n = 3). Since the first discovered of BSCCO in 1998 until now, there have been many studies related to BSCCO fabrication with various methods and the addition of other elements with the aim of knowing its effect on its physical and electrical properties. In this study, the authors conducted experiments regarding the fabrication of BSCCO materials with the addition of Titanium (TiO2). There were four samples that were successfully formed with the more dominant and stable Bi-2212 phase formed. The morphology and distribution of each element is shown by SEM and EDS Mapping tests. To determine the superconductivity, including the critical temperature (Tc), of each sample, a superconductivity test was performed using a cryogenic magnetometer."

"Thermal waters at Ciarrinem and Cilayu,Pameungpeuk, West Java, Indonesia have different characteristics: Cairinem water is a steam heated sulfate type and accurs as hot springs,whereas Cilayu water discharges as hot pools and is a chloride water type

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"Proses pembentukan logam dikenal luas di bidang manufaktur. Salah satu produk pembentukan adalah welded eye bolt yang dibentuk pada temperatur tinggi. Beberapa masalah ditemui pada welded eye bolt dimana terjadi kegagalan berupa retak maupun ukuran penampang yang tidak merata sepanjang daerah pembentukan panas.Pada penelitian ini diuji keuletan temperatur tinggi baja karbon batangan ASTM A36 sebagai bahan dasar welded eye bolt, agar diperoleh hubungan antara temperatur terhadap mampu bentuk material sebagai bahan masukan dalam .proses pembentukan panas berikutnya. Metode penelitian meliputi karakterisasi material melalui analisis kimia dan pengujian tarik pada temperatur ruang dan temperatur tinggi (T600, T700, T800). Kemudian dilakukan pembentukan welded eye bolt berdiameter 16, 20, 24 mm pada T600, T700, T800- Sampel proses pembentukan kemudian diuji kekerasan dan dilakukan pengamatan struktur mikro dengan menggunakan SEM.Hasil pengujian tarik bahan dasar welded eye bolt pada temperatur ruang, Tsoo, T700, Tsoo memperlihatkan bahwa kekuatan tarik dan luluh turun dengan naiknya temperatur. Pengamatan struktur mikro menunjukkan bahwa ukuran butir pada Teoo dan T700 relatif sama, namun pada T800 ukuran butir lebih besar. Pengamatan struktur mikro juga menunjukkan terdapatnya inklusi. Hasil optimal pembentukan menunjukkan bahwa T600 dan T700 lebih baik dibandingkan pada T800,- Sedangkan keuletan T700 lebih baik daripada T600- Jadi pembentukan komponen welded eye bolt pada T700 lebih direkomendasikan.

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Metal forming is applied widely in the field of manufacturing. One forming component is the welded eye bolt which is formed at a high temperature. Some problems have been found during forming which include cracks and the cross section not being uniform along the forming area.

This research investigated the high temperature ducility of round bar carbon Steel ASTM A36, which will be formed into welded eye bolts, so that we can establish the relationship between the forming temperature and formability of the material as an input in next hot forming process. The method of this research consist of characterizing the material by Chemical analysis and conducting the tensile test at room temperature and high temperatures (T600, T700, T800)- The forming process was then continued for the welded eye bolt components which have 16, 20, and 24 mm diameter at T600, T700, T800- Samples of the forming process were hardness tested and microstructure was observed by using SEM.

The tensile testing results of the welded eye bolt material at room temperature and T600, T700, T800 showed that the tensile strength and yield strength decreased at higher temperatures. Microstructure analysis showed that the grain size at Tsoo and T700 are similar, but the grain size at Tgoo is bigger. Inclusions were also observed. Optimum result show forming at T600 and T700 are better than T800, and ductility of T700 is better than T800- From these results T700 is recommended for the forming process of welded eye bolt components."

"ABSTRACTPLTMG Panaran adalah Pembangkit Listrik Tenaga Mesin Gas yang berlokasi di Panaran PBatam dimana setiap unit mesin di PLTMG panaran memiliki 6 buah finfan cooler yang berfungsi untuk mendinginkan suhu HT (High Temperature) pada mesin. Saat ini pengoperasian finfan cooler di PLTMG Panaran di operasikan secara manual oleh operator dengan melihat kondisi pembebanan serta suhu luar ruangan (ambient temperature). Terdapat beberapa kekurangan dalam pengoperasian secara manual diantaranya inefisiensi daya serta kemungkinan derating engine atau penurunan daya mampu ketika operator lupa atau tidak tepat dalam menentukan jumlah aktifnya motor finfan cooler. Sistem kontrol otomatis dengan metode fuzzy ini merupakan sistem yang tepat untuk memperbaiki kelemahan sistem kontrol manual yang ada di PLTMG saat ini. Sistem ini akan mengatur putaran motor sesuai dengan kebutuhan atau kestabilan unit mesin secara otomatis berdasarkan kondisi pembebanan serta suhu luar ruangan. Diharapkan dalam pengoperasian dapat memudahkan operator serta menurunkan ineffisiensi dalam pemakaian daya motor finfan dan juga diharapkan sistem kontrol cerdas dapat diterapkan oleh PT. PLN Persero untuk proyek 35.000 MW. "

"The second edition was significantly extended by including film-substrate lattice matching and buffer layer considerations in thin film HTSCs, brick-wall microstructure in the epitaxial films, electronic structure of the CuO2 layer in cuprates, s-wave and d-wave coupling in HTSCs and possible scenarios of theories of high Tc superconductivity."

"Nuclear Magnetic Resonance (NMR) has been a fundamental player in the studies of superconducting materials for many decades. This local probe technique allows for the study of the static electronic properties as well as of the low energy excitations of the electrons in the normal and the superconducting state. On that account it has also been widely applied to Fe-based superconductors from the very beginning of their discovery in February 2008. This dissertation comprises some of these very first NMR results, reflecting the unconventional nature of superconductivity and its strong link to magnetism in the investigated compounds LaO1–xFxFeAs and LiFeAs."

"Reaktor tipe HTGR merupakan reaktor berpendingin gas temperatur tinggi (~900°C). Terdapat 2 tipe elemen bakar HTGR yaitu praismatik dan pepple bed. Kedua tipe elemen bakar tersebut tersusun dari partikel berlapis TRISCO yang terdiri dari lapisan IPyC, SiC, dan OPyC yang berfungsi sebagai pengungkung produk fisi dan menjaga integritas bahan bakar. Reaktor beroperasi dengan temperatur tinggi, sehingga kinerja/kemampuan bahan bakar dalam menajan produk fisi perlu diketahui. Tujuan studi adalah untuk memperoleh pemahaman tentang karakteristik produk fisi yang dihasilkan bahan bakar, karakteristik penghalang dan kinerja bahan bakar dalam menahan produk fisi. Metode yang digunakan adalah kajian dan analisis dengan mengevaluasi kemampuan penghalang (barrier) dalam menahan produk fisi pada elemen bakar primatik dan pebble. Hasil studi menunjukkan bahwa terdapat beberapa mekanisme beberapa produk potensial lepasnya produk fisi, yaitu: difusi melalui lapisan, kerusakan lapisan, korosi SiC oleh produk fisi palladium dan dekomposisi termal SiC. Bahan bakar merupakan penghalang pertama terhadap beberapa mekanisme potensial lepasnya radionuklida produk fisi sedangkan lapisan SiC merupakan penghalang utama yang menahan sebagian besar produk fisi gas dan padat pada temperatur operasi normal (< 1250°C). "

"Cadmium sulphide (CdS), a member of group II-VI semiconductors, is a promising material based on its applications. The present investigations describe the preparation and electrical characterization of CdS thin films. CdS thin films with thickness of 1000 nm were deposited by vacuum evaporation at room temperature. Characteristic parameters of Schottky junctions formed by a thermal vapor deposition of 500 nm of Al films on pre-coated CdS glass substrates were obtained experimentally from the I-V characteristics in the temperature range of 303–393 K. Diode parameters, such as the zero-bias barrier height ?b0, flat band barrier height ?bf, ideality factor ?, and series resistance RS were investigated using the thermionic emission method."

"Area prospek panasbumi Lili, Sulawesi Barat, Indonesia merupakan salah satu daerah prospek yang berasosiasi dengan aktivitas vulkanik yang terjadi sejak zaman Tersier. Aktivitas vulkanik ini diperkirakan merupakan aktivitas gunungapi bawah laut yang berkembang menjadi gunungapi darat berumur Kuarter bawah. Area prospek panasbumi ini memiliki mata air panas tipe klorida, dan tipe bikarbonat yang tersebar di sekitar area prospek. Dari hasil perhitungan geotermometer area prospek panasbumi Lili memiliki temperatur 189-201 °C, yang dikategorikan sebagai moderate to high temperature geothermal system. Untuk mengetahui batas, kedalaman, dan geometri dari reservoir yang ada, dilakukan pengukuran dengan metode Magnetotelluric (MT) serta metode geofisika lainnya sebagai pendukung seperti metode gravitasi, geomagnet, dan geolistrik. Pengukuran dilakukan dengan desain gridding agar dapat diketahui penyebaran resistivitas dari arah Utara-Selatan maupun Barat-Timur. Data MT tersebut dikoreksi terlebih dahulu terhadap efek statik dan noise dengan menggunakan Mat-Lab dan Site to Site Reference sebelum nantinya siap diinterpretasi. Pemodelan sistem panasbumi dari data magnetotellurik dengan menggunakan analisa 2-dimensi dan 3-dimensi. Hasil area prospek berada dari arah barat daya hingga ke tengah lokasi pengukuran menerus ke utara. Rekomendasi pengeboran di sekitar daerah outflow dengan kedalaman sekitar 1.8 km dekat dengan zona patahan yang mempunyai permeabilitas yang lebih besar untuk mendapatkan fluida panasnya.

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Geothermal prospect area in Lili, West Celebes, Indonesia is one of the prospect area in Indonesia associated by volcanic activity which happened since tertiary. This volcanic activity is predicted as undersea volcano which grown become to volcano quartenary. This geothermal prospect area has chloride and bicarbonate hot springs. Based on geothermometry calculation the geothermal prospect area of Lili has temperature 189-201 °C which is categorized as a moderate to high temperature geothermal system. To estimate the boundary, depth, and geometry of the reservoir, Magnetotelluric (MT) and other geophysics methods were used such as gravity, geomagnetic, and geoelectric method as supporting data.

Data acquisition was designed gridding method to delineated resistivity distribution in North-South or West-East orientation. MT data was then corrected for static effect and possible noise using Mat-lab and Site to site reference before comprehensive interpretation. Modeling of the geothermal system was carried out by using 2-dimensional MT resistivity and 3-dimensional visualization. As a result, the prospect area is exist in south west until center of measurement area. Pattern of this zone still continue to the north of measurement area. In addition, drilling recommendation is proposed around the outflow in Lili with depth at 1.8 km near the fault zone to get the hot fluid."