Judul: Desain Komputasi Material Katoda Baterai Berbasis Na-Mn-O-(Ni) Na2Mn3-zNizO7
Abstrak: Perkembangan teknologi dibidang komputasi yang begitu pesat membuat eksperimen yang bersifat real dapat dimodelkan atau diprediksi secara komputasi yang tentunya akan dapat membantu dalam penekanan biaya dan penghematan akan penggunaan sumber daya alam. Salah satu aplikasi pemodelan komputasi yang cukup luas digunakan adalah penentuan rapatan energi dan sifat elektronik dari suatu material. Salah satu material yang masih dalam proses pengembangan dan berpotensi diaplikasian secara luas adalah material berbasis sodium pada baterai. Penulisan tesis ini berfokus pada proses penentuan rapatan energi dan sifat elektronik pada model baterai sodium (SIB) dengan doping nikel dan kombinasi mangan-oksigen (Na2Mn3-zNizO7) menggunakan perhitungan First principle pada software Quantum Espresso. Selain faktor kelimpahan natrium dan nikel di alam sebagai alternatif untuk mengatasi keterbatasan material litium, material Na2Mn3-zNizO7 memiliki kemiripan struktur dengan baterai berbasis litium yang sudah di gunakan secara luas. Proses perpindahan ion Na+ dan energi aktivasi telah disimulasikan, begitu juga tegangan dan sifat elektronik dari material telah dihitung dan menunjukkan adanya potensial untuk dijadikan sebagai katoda. Diharapkan akan adanya penelitian yang lebih lanjut terkait dengan karakterisitik lain yang belum dihitung seperti kestabilan terhadap suhu dan daya tahan. Katoda yang telah dirancang dapat di kombinasikan dengan elektrolit berbasis pelarut organik, sehingga tujuan pendayagunaan potensi alam domestik yang ramah lingkungan dapat tercapai.
Keyword: DFT, Molecular Dynamics, Quantum Espresso, Renewable Energy, SIB

Judul: Effects of NaMnN2 Material Phase Differences on the Properties and Performance of Sodium Ion Battery Cathodes
Abstrak: Kemajuan teknologi menyebabkan kebutuhan akan baterai isi ulang meningkat. Namun baterai ion litium sebagai baterai yang umum digunakan mengalami kenaikan harga yang tinggi karena kelangkaan litium di alam. Baterai ion natrium sebagai baterai alternatif dari baterai ion litium belum menemukan kandidat material katoda yang tepat. NaMnN2 dari keluarga Layered N-based TMDs-like diharapkan dapat menjadi material katoda baterai ion natrium yang murah dan baik. Density Functional Theory digunakan dalam penelitian ini untuk membuktikan pengaruh fasa terhadap sifat elektronik dan performansi material katoda NaMnN2, sehingga dapat diperoleh fasa terbaik bagi keluarga Layered N-based TMDs-like sebagai katoda baterai ion natrium. Hasil penelitian menunjukan bahwa secara teoretis NaMnN2 berpotensi sebagai katoda baterai ion natrium yang memiliki performansi baik. Selain itu, NaMnN2 fasa 2H memiliki keunggulan pada kestabilan siklus, memiliki konduktivitas yang sangat baik, serta mengalami difusivitas ion Na yang baik dengan energi penghalang sebesar 0,41 eV. Material NaMnN2 fasa 1T unggul dalam tegangan yang lebih tinggi, mencapai 3,93 V, serta memiliki rapat energi yang besarnya mencapai 995,22 Wh/kg., Technological advancements have caused the need for rechargeable batteries to increase. However, lithium ion battery as a commonly used battery has experienced a high price increase due to the scarcity of lithium in nature. Sodium ion battery as an alternative battery to lithium ion battery has not found the right cathode material candidate. NaMnN2 from the Layered N-based TMDs-like family is expected to be a cheap and good sodium ion battery cathode material. Density Functional Theory is used in this study to prove the effect of phase on the electronic properties and performance of NaMnN2 cathode material, so that the best phase can be obtained for the Layered N-based TMDs-like family as a sodium ion battery cathode. The results showed that theoretically NaMnN2 has the potential as a cathode of sodium ion battery which has good performance. In addition, 2H-phase of NaMnN2 has advantages in cycle stability, has excellent conductivity, and experiences good sodium ion diffusivity with a barrier energy of 0,41 eV. The 1T phase NaMnN2 material excels in higher voltages, reaching 3,93 V, and has an energy density of up to 995,22 Wh/kg.
Keyword: cathode, DFT, phase, Quantum Espresso, SIB

Judul: Kajian Keberadaan Virus Avian Influenza pada Unggas di Pasar Burung Pramuka, Jakarta
Abstrak: Avian Influenza (AI) which is caused by influenzavirus A of the family Orthomyxoviridae cause an important impact, including in health, social and economic sectors. AI viruses (AIV) can infect various birds and mammals, therefore bird market as a meeting place for human and poultry can potentially transmit AI virus among birds or from birds to human. Indonesia is a habitat of various bird species; therefore research about AIV on bird, especially which are sold in the Pramuka Bird Market, as the biggest bird market in Jakarta, is urgently needed. In general, the aim of this study was to examine the presence of AIV in various bird species sold in Pramuka Bird Market, Jakarta. Specifically, the aims of this study were: (1) to assess the presence of H5 AI virus in oropharyngeal swab, cloacal swab, and fecal samples of various bird species using real time Reverse Transcriptase-Polymerase Chain Reaction (rRT-PCR); (2) to detect the presence of antibodies against AIV (H5) in various bird species using hemagglutination inhibition (HI) test, and (3) to determine the relationship among weather and geographic origin of birds to the prevalence of AIV. During April until September 2011, a number of 862 field samples from 28 families and 96 bird species were collected in Pramuka Bird Market, Jakarta. These field samples consisted of 649 fecal samples, 114 cloacal swab samples, and 99 oropharyngeal swab samples. As many as 7 of 649 faecal samples (1.08%) were positive AI. However, none cloacal or oropharyngel swab were positive AI. Positive fecal samples were detected in four bird species, which are three magpie-robins (Copsychus saularis, family Turdidae), two white-eyes (Zosterops palpebrosus, family Zostropidae), a yellow-vented bulbul (Pycnonotus goiavier, family Pycnotidae), and a robin (Leiothrix lutea, family Sylviidae). In addition to field samples, during April until September 2011, 178 birds from 21 families and 47 species were purchased from the same bird market. From 178 birds, two birds (1.12%), which were two white-eyes (Zosterops palpebrosus, family Zostropidae), were positive AI. The whole positive samples were from Passeriformis order. However, based on rRT-PCR result, there were no H5 positive samples. A number of 163 serum samples were collected from 178 purchased birds from Pramuka Bird Market. Based on HI test using antigen A/Legok/IPB-SGT/1/2004 (H5N1) and A/Ck/West Java/PWT-Wij/2006 (H5N1), seven of 163 birds (4.29%) had positive antibodies to AI. There were differences in HI titers between the two antigens. By using A/Legok/IPB-SGT/1/2004 (H5N1) antigen, two sample were strongly positive (titers ≥ 24), while the other five samples were weakly positive (titers <24). Strongly positive results were obtained from two scooty-headed bulbul (Pycnonotus aurigaster, family Pycnotidae). While the weakly positive results were obtained from a swan (Cygnus sp., family Anatidae), a duck (Anas sp., family Anatidae), a munia (Lonchura maja, family Ploceidae), a spotted-dove (Streptopelia chinensis, family Columbidae), and a black-crowned iv night heron (Nyctorax nyctorax, family Ardeidae). By using A/Ck/West Java/PWT-Wij/2006 (H5N1) antigen, the average HI titer obtained was higher. Five samples were strongly positive (Lonchura maja, Cygnus sp., Nyctorax nyctorax, and two Pycnonotus aurigaster), while samples from Anas sp. and Streptopelia chinensis were weakly positive.
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