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Abstrak :
Saat ini divais spintronik untuk penyimpan data berbasis magnet telah menjadi perhatian para peneliti. Salah satu bahan yang berpotensi adalah feromagnetik berbentuk nanowire, seperti Racetrack Memory yang cara kerjanya berdasarkan pergerakan domain wall (DW). Pada penelitian ini, telah dilakukan analisa osilasi dan struktur domain wall di dalam kontriksi notch pada bahan feromagnetik (Fe, Ni, dan Co) berbentuk nanowire. Simulasi mikromagnetik menggunakan perangkat lunak bersifat publik bernama Object Oriented Micromagnetic Framework berdasarkan persamaan dinamika spin magnet Landau-Lifshitz- Gilbert. Ukuran nanowire 2000 200 5 nm, di bagian tengah diberikan notch ganda bersifat simetris berbentuk lengkung, segitiga, dan persegi. Di tengah notch diletakkan sebuah tipe struktur DW berbentuk transverse-wall (TW) dengan konfigurasi head-to-head. Penelitian diawali dengan pengamatan kondisi ground state yang diperoleh hasil bahwa DW stabil di tengah notch. Selanjutnya diberi medan magnet bolak-balik dengan amplitudo tetap 2 mT dan variasi frekuensi dari 0,3 -2,0 GHz. Hal yang menarik, terjadi osilasi DW dengan struktur TW yang stabil. Nilai amplitudo osilasi DW terlihat semakin turun dengan bertambahnya frekuensi medan bolak-balik, artinya notch berfungsi sebagai potensial pinning. Selanjutnya dilakukan perhitungan lebar DW berdasarkan FWHM dari data magnetisasi My dan hasil nilai lebar DW tergantung pada bentuk notch. Dari nilai lebar DW juga dihitung massa DW dengan memberlakukan DW sebagai model osilasi harmonik sederhana.

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Recently, the development spintronic devices become great attention because its potential for magnetic storage and magnetic sensor devices. One of the materials has potential is the ferromagnetic nanowire, such as Racetrack Memory based on the domain wall motion. In this study, we have analyzed the oscillation and structure of domain wall in the ferromagnetic nanowire Co, Fe, dan Ni. We used micromagnetic simulation with public micromagnetic software Object Oriented Micromagnetic Framework (OOMMF) based on the spin dynamic Landau- Lifshitz-Gilbert (LLG) equation. The dimension of nanowire is 2000 × 200 × 5 nm with double notch is positioned at the center of the nanowire. The shape of notchs consisted of arch-notch, triangle-notch, and rectangular-notch with initial a head-to-head transverse wall (TW) is located at the center of nanowire. Firstly, we investigated the DW in ground state condition and we found the DW is stable at the center of nanowire. Secondly, we applied AC magnetic field with various frequency from 0.3 GHz-2.0 GHz and the amplitude of AC field is fixed to be 2 mT. Interestingly, we observed the DW oscillation with stably TW structure. Increasing the frequency of AC field, the amplitude of DW oscillation showed to decrease. This mean that the notch acted as the pinning potential. Furthermore, we also calculated the DW width based on FWHM from My magnetization and depended on the shape of the notch. From DW width, we also determined the DW mass with driven simple harmonic model.

Abstrak :
[ABSTRAK
Material serpih adalah sejenis serpih minyak yaitu material clay atau karbonat yang mengandung banyak organik belum matang, apabila dipanaskan pada suhu tertentu, kandungan organiknya menjadi matang dan berubah secara fisika dan kimia, sehingga dapat menghasilkan bahan energi seperti migas. Dalam penelitian ini campuran material dimodifikasi dengan perbandingan: A=B, AB dan AB. Pengujian TOC menghasilkan clay-organik (SMC) dan karbonat-organik (SMK) menunjukkan kualitas yang sangat baik sebagai serpih minyak (TOC≥12.0%), yang diperkuat hasil analisis SEM (morfologi dan komposisi) dan XRD (interaksi dua material). Hasil analisis Termogravimetri menunjukkan energi aktivasi material serpih clay (209-355 kJ/mol) lebih kecil dibanding karbonat (749-1339 kJ/mol), dan temperatur untuk proses reaksi material serpih clay (40-600OC) lebih kecil dibanding karbonat (75-740OC). Karakteristik tersebut menyebabkan tingkat maturasi material serpih clay lebih cepat dibanding karbonat, diperkuat Tmax serpih clay (315-323OC) lebih kecil dibanding Tmax serpih karbonat (415-493OC). CEC 2 (serpih minyak) memiliki karakteristik yang sama dengan serpih clay (Ea=239 kJ/mol dan T=40- 600OC). OD1-Ast3 memiliki tingkat maturasi yang paling bagus (Ea=234 kJ/mol dan Tmax=315OC) sesuai dengan serpih minyak (CEC 2). Hasil pengujian Rock Eval Pyrolisis menunjukkan material serpih clay dan karbonat mempunyai potensi tinggi (menghasilkan oil dan gas). Hasil pemanasan material serpih diperkuat oleh hasil pengujian FTIR yaitu senyawa dengan gugus fungsi tertentu terlepas dan muncul puncak baru di bilangan gelombang 2900 cm-1 yang menunjukkan keberadaan hidrokarbon ikatan tunggal dari rantai karbon panjang C-H.;

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ABSTRACT
The material is a kind of shale oil shale is clay or carbonate material containing organic many immature, when heated to a certain temperature, the organic content of becoming mature and change in physics and chemistry, so it can produce energy materials such as oil and gas. In this study a mixture of materials modified by comparison: A=B, AB and A>B. TOC testing of clay-organic (SMC) produce and organic carbonates (SMK) demonstrate excellent quality as shale oil (TOC≥12.0%), which confirmed the results of scanning electron microscopy (SEM) analysis (morphology and composition) and X-ray diffraction (XRD) (interaction of two materials). The results of thermogravimetric analysis showed activation energy shale clay material (209-355 kJ/mol) is smaller than the carbonate (749-1339 kJ/mol), and the temperature of the reaction process shale clay material (40-600OC) is smaller than the carbonate (75- 740OC). These characteristics cause the maturation level of clay shale material faster than carbonate, shale clay reinforced Tmax (315-323OC) is smaller than Tmax flakes carbonate (415-493OC). CEC 2 (shale oil) has the same characteristics as the flakes of clay (Ea=239 kJ/mol and T=40-600OC). OD1-Ast3 have the most good maturation rate (Ea=234 kJ/mol and Tmax=315OC) in accordance with the shale oil (CEC 2). Test results show the Rock Eval Pyrolisis clay shale and carbonate material has a high potential (produce oil and gas). Results heating shale material reinforced by FTIR testing results are compounds with specific functional groups apart and a new peak appeared at wavenumber 2900 cm-1 which indicate the presence of hydrocarbons single bonds of the carbon chain length of CH.;The material is a kind of shale oil shale is clay or carbonate material containing organic many immature, when heated to a certain temperature, the organic content of becoming mature and change in physics and chemistry, so it can produce energy materials such as oil and gas. In this study a mixture of materials modified by comparison: A=B, AB and A>B. TOC testing of clay-organic (SMC) produce and organic carbonates (SMK) demonstrate excellent quality as shale oil (TOC≥12.0%), which confirmed the results of scanning electron microscopy (SEM) analysis (morphology and composition) and X-ray diffraction (XRD) (interaction of two materials). The results of thermogravimetric analysis showed activation energy shale clay material (209-355 kJ/mol) is smaller than the carbonate (749-1339 kJ/mol), and the temperature of the reaction process shale clay material (40-600OC) is smaller than the carbonate (75- 740OC). These characteristics cause the maturation level of clay shale material faster than carbonate, shale clay reinforced Tmax (315-323OC) is smaller than Tmax flakes carbonate (415-493OC). CEC 2 (shale oil) has the same characteristics as the flakes of clay (Ea=239 kJ/mol and T=40-600OC). OD1-Ast3 have the most good maturation rate (Ea=234 kJ/mol and Tmax=315OC) in accordance with the shale oil (CEC 2). Test results show the Rock Eval Pyrolisis clay shale and carbonate material has a high potential (produce oil and gas). Results heating shale material reinforced by FTIR testing results are compounds with specific functional groups apart and a new peak appeared at wavenumber 2900 cm-1 which indicate the presence of hydrocarbons single bonds of the carbon chain length of CH., The material is a kind of shale oil shale is clay or carbonate material containing organic many immature, when heated to a certain temperature, the organic content of becoming mature and change in physics and chemistry, so it can produce energy materials such as oil and gas. In this study a mixture of materials modified by comparison: A=B, AB and A>B. TOC testing of clay-organic (SMC) produce and organic carbonates (SMK) demonstrate excellent quality as shale oil (TOC≥12.0%), which confirmed the results of scanning electron microscopy (SEM) analysis (morphology and composition) and X-ray diffraction (XRD) (interaction of two materials). The results of thermogravimetric analysis showed activation energy shale clay material (209-355 kJ/mol) is smaller than the carbonate (749-1339 kJ/mol), and the temperature of the reaction process shale clay material (40-600OC) is smaller than the carbonate (75- 740OC). These characteristics cause the maturation level of clay shale material faster than carbonate, shale clay reinforced Tmax (315-323OC) is smaller than Tmax flakes carbonate (415-493OC). CEC 2 (shale oil) has the same characteristics as the flakes of clay (Ea=239 kJ/mol and T=40-600OC). OD1-Ast3 have the most good maturation rate (Ea=234 kJ/mol and Tmax=315OC) in accordance with the shale oil (CEC 2). Test results show the Rock Eval Pyrolisis clay shale and carbonate material has a high potential (produce oil and gas). Results heating shale material reinforced by FTIR testing results are compounds with specific functional groups apart and a new peak appeared at wavenumber 2900 cm-1 which indicate the presence of hydrocarbons single bonds of the carbon chain length of CH.]

Abstrak :
ABSTRAK
Pada penelitian ini telah disintesis material komposit berbasis logam atau metal matrix composite MMC . Komposisi Al/SiC, dan AlCu/SiC sebagai material komposit hasil peleburan dan pemadatan solidifikasi dilakukan proses lebih lanjut dengan menggunakan penekanan panas 5 ton hot press pada temperatur 300o C. Analisis data XRD merupakan fasa tunggal Al dengan sistem kristal FCC yang memiliki kontanta kisi 4.0560 dengan bidang kristal pada intensitas terbesar 111 , 002 , 022 , 113 , 222 dan telah terjadi perubahan arah bidang kristal secara signifikan akibat penekanan panas hot press dan pendinginan cepat arah sejajar yaitu pada bidang 111 dan 002 dan arah tegak lurus atau melintang pada bidang kristal 022 . Hasil foto SEM pada permukaan morfologi padatan Al, Al/SiC 4 berat, dan AlCu/SiC 4 , permukaan pada arah sejajar tampak lebih merata dan lebih homogen secara bentuk struktur. Sedangkan permukaan pada arah tegak lurus atau penampang melintang sampel memiliki bentuk struktur yang berbeda dan membentuk arah memanjang tegak lurus terhadap arah penekanan pada proses penekanan panas. Nilai kekerasan Vickers HV secara keseluruhan sampel komposit AlCu/SiC hasil penekanan panas hot press lebih besar dibandingkan dengan Al/SiC untuk pendinginan lambat dan cepat. Juga termasuk dimana posisi permukaan melintang atau tegak lurus perpendicular memiliki nilai HV yang lebih besar dibandingkan dengan permukaan sejajar in-plan . Laju korosi mulai dari yang terbesar sampai terkecil adalah Al 1,8986. 10-3 , Al/SiC 1,2509. 10-3 mm/tahun , AlCu 1,1716. 10-3 mm/tahun , AlCu/SiC 1,1144. 10-3 mm/tahun , dan Al2024 1,0648. 10-3 mm/tahun . Hal ini menunjukkan bahwa ketahanan korosi diperoleh pada sampel AlCu dan AlCu/SiC.

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ABSTRACT
Hybrid aluminum metal or metal matrix composite MMC have been synthesized and characterized. The composition of Al SiC, and AlCu SiC as a composite material melting and solidification solidification process is carried further by using heat suppression 5 tons hot press at a temperature of 300oC. Analysis of x ray Diffraction XRD show that the spectrum indicates a single phase Al with crystal system face center cubic FCC which constants lattice 4.0560 and the crystal orientations are 111 , 002 , 022 , 113 , and 222 . The direction of the crystal orientations were influenced by compression heat hot press and fast cooling. It can be seen from the direction 111 and 002 . The SEM images on the surface morphology of solids Al, Al SiC 4 by weight, and AlCu SiC 4 , the surface in a direction parallel seems more equitable and more homogen in the form of the structure. While, the surface in the direction perpendicular or cross sectional sample has a form different structures and forming a longitudinal direction perpendicular to the direction of the emphasis on hot press process. The Hardness Vickers value HV overall composite sample AlCu SiC heat suppression results hot press is greater than the Al SiC for slow and fast cooling. Also included where the surface position of transverse or perpendicular perpendicular has a HV value greater than the surface parallel in plan . The corrosion rate starting from the largest to smallest is Al 1.8986 x10 3 mm y , Al SiC 1.2509 x 10 3 mm y , AlCu 1.1716 x 10 3 mm y , AlCu SiC 1.1144 x 10 3 mm y , and Al2024 1.0648 x 10 3 mm y . These indicated that the corrosion resistance obtained on the sample AlCu and AlCu SiC.