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"ABSTRAKDesertasi ini membahas tentang karakteristik Paduan Mg3CoNi2 Sebagai Penyerap Hidrogen. Paduan dibuat dengan metode pemaduan mekanik. Untuk mendapatkan sampel yang optimal telah dilakukan variasi pembuatan sample dengan mengombinasikan rasio berat bola terhadap sampel 1:1 dan 8:1 dengan waktu milling selama 10 menit, 5, 10, 15, 20, 30, 40 dan 60 jam. Peralatan milling adalah konvensional milling dan High Energy Milling SPEX 8000. Dari pengukuran XRD diketahui bahwa semua sampel mengalami oksidasi dengan bertambahnya waktu milling yaitu terbentuknya fasa MgO yang semakin banyak. Untuk mengurangi oksidasi dilakukan teknik pemaduan basah dengan cara menambahkan toluen ke dalam sampel yang akan dimilling. Dari pengukuran XRD diketahui bahwa fasa yang terbentuk sebagian besar adalah Mg2Ni dan sedikit MgNi2 sedangkan fasa Mg2Co dan MgCo2 tidak terbentuk. Hal ini karena energi pembentukan Mg2Co dan MgCo2 lebih besar dari pada pembentukan Mg2Ni dan MgNi2. Fasa Mg2Ni yang terbentuk mengalami penurunan parameter kisi dari 5,22 nm menjadi 4,59 nm dan dari 13,29 nm menjadi 11,72 nm. Dari hasil pengamatan dengan SEM juga menunjukkan pengurangan ukuran partikel dan dari pengamatan dengan SANS menunjukkan penambahan luas permukaan. Kapasitas penyerapan hidrogen terbanyak diperoleh pada sampel yang dimilling selama 40 jam pada temperatur 200_C, yaitu sebesar 3,3 % berat. Keberadaan hidrogen di dalam sampel ditunjukkan dengan terjadinya perubahan ukuran kristal pada sudut 40,95_ dan pada sudut 47,7_. Keberadaan hidrogen dalam sampel juga dibuktikan dengan turunnya intensitas hamburan neutron pada pengamatan dengan menggunakan SANS.

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ABSTRACTThis dissertation is discussing about the characteristics of Mg3CoNi2 alloy as a hydrogen storage. The alloy is made by mechanical alloying method. To obtain the optimal sample, a variation making of sample has been done by combining the ball to the sample weight ratio of 1:1 and 8:1 with the milling time of 10 s, 5, 10, 15, 20, 30, 40 and 60 hours. The milling apparatus used is a conventional milling and a High Energy Milling SPEX 8000. From the XRD measurement results it is known that all obtained by dry preparation method sample are oxidized into MgO phase, especially for longer milling time. To reduce the oxidation effects a wet alloying method has been done by adding toluene to the sample to be milled. From the XRD measurement results it is known that the phases formed are mostly Mg2Ni and small amount of MgNi2, while the phases of Mg2Co and MgCo2 are not formed. This is because the energy of Mg2Co and MgCo2 formations are bigger than those for Mg2Ni and MgNi2 formation. The lattice parameters of Mg2Ni formed decrease from 5,22 nm to 4,59 nm and from 13,29 nm to 11,72 nm. From the observation results using SEM the decrease of particle size is also shown and from SANS investigations it is shown that surface area increased with increasing milling time. The highest hydrogen absorption capacity was obtained from 40 hours milled sample at hydriding temperature of 200_C. The presence of hydrogen in the sample is indicated the change of the crystallite size calculated the angle of 40,95_and 47,7_. The presence of hydrogen in the sample is also proven with the decrease of neutron scattering intensity analyzed using SANS."

"The effect of hydrogen and hydrides on the integrity of zirconium alloy components : delayed hydride cracking provides a detailed explanation focusing on the properties of hydrogen and hydrides in these alloys. Whilst the emphasis lies on zirconium alloys, the combination of both the empirical and mechanistic approaches creates a solid understanding that can also be applied to other hydride forming metals. This up-to-date reference focuses on documented research surrounding DHC, including current methodologies for design and assessment of the results of periodic in-service inspections of pressure tubes in nuclear reactors. Emphasis is placed on showing how our understanding of DHC is supported by progress in general understanding of such broad fields as the study of hysteresis associated with first order phase transformations, phase relationships in coherent crystalline metallic solids, the physics of point and line defects, diffusion of substitutional and interstitial atoms in crystalline solids, and continuum fracture and solid mechanics. Furthermore, an account of current methodologies is given illustrating how such understanding of hydrogen, hydrides and DHC in zirconium alloys underpins these methodologies for assessments of real life cases in the Canadian nuclear industry."

"Bronze (Cu - Sn) are the most commonly used materials for self lubricating bearings produced by powder metallurgy process. The characteristics and the performance of these bearings are highly dependent on the chemical composition and the microstructure, especially the fraction of open porosity. While the microstructure fully dependent on the control of the compaction and sintering process. In this study, the effects of three parameters were investigated : (1) the Sn content (5 % , 10 % and 15 %); (2) the compaction pressure (200 MPa, 300 MPa and 400 MPa); and (3) the sintering temperature (800°C, 850°C and 900°C) on the characteristics of Cu-Sn P/M alloys. The increase in compaction pressure will increase the green density and the green strength, while the increase in Sn content will decrease the green strength. In general, the increase in sintering temperature will decrease the sintered density followed by the swelling of the sintered. The increase in sintering temperature also decrease the macrohardness and the compressive strength. The amount of porosity and the second phase , 8 phase - Cu31Sna, formed during sintering is increased with the increase in Sn content and then followed by the increase in grain size."

"Research and commercial activity in developing hydrogen as a fuel is driving increased attention on hydrogen-materials interactions. In particular, a renewed and intensifying interest in developing hydrogen fuel cells has prompted extensive research with the objective to enable the safe design of components for transporting and storing hydrogen fuel. This volume is the proceedings from the premier conference on hydrogen effects in materials, bridging scientific research and engineering applications. The proceedings volume highlights several themes: the technological importance of hydrogen effects on structural materials; the impact of bridging science and engineering; and the opportunity to apply new research tools, including simulation techniques as well as experimental methods."

"Jaringan internet selain mempercepat era informasi juga telah merevolusi kemampuan manusia dan juga mesin. Seiring perkembangan teknologi danmaraknya otomasasi, kecerdasan buatan (AI) mengusung ancaman signifikan terhadap diseminasi informasidi media digitaldan internet. Teknologi AI yang kian realistis dan sulit untuk terdeteksi menambah keprihatinan public terhadap potensi penyalahgunaan. Dengan itu, penelitian ini beragumen bahwa era pasca-kebenaran telah diakselerasi dengan munculnya kecerdasan buatan dan algoritmaprediksi yang berkemampuan untuh mengubahrealita dan persepsi. Teknologi hiper-realistis tersebut dapat membawa niatan jahat seperti memaksa dan mengintimidasi suatu individu atau organisasi, menyebarkan informasi palsu, sabotase, dan sebagainya;mengakibatkan runtuhnya keaslian dan kebenaran. Maka dari itu, penelitian ini bertujuan untuk mengeksplorasi implikasi sosial, politik dan budaya dari manipulasi yang dihasilkan AI yang tersebar di media sosial dan internet.The birth of the internet had accelerated the information age and revolutionized the capabilities of both man and machine. Digital media and the internet are now the facilitators of information. However, with rapid development towards automation, technology had now posed a significant threat to communication as artificial intelligence are now the perpetrators of the diffusion of misinformation. As the technology is increasingly realistic and undetectable, concerns are rising over its misuse. This paper argues that the world is heading towards a post-truth era with the emergence of artificial intelligence and predictive algorithm altering reality as we know it. Such hyper-realistic technology can host malicious intentions such as to coerce and intimidate an individual or organization, spread misinformation, sabotage, etc; resulting in the demise of authenticity and truth. This paper aims to explore the social and political implications of AI generated manipulations spread across social media and the internet. 

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