Judul: Pengaruh Variasi Konsentasi Pendadah RuO2 Terhadap Struktur Kristal Dan Sifat Optik Dari Film Tipis BaTiO3
Abstrak: Pembuatan film tipis BaTiO3 bertujuan menganalisis sifat optik, struktur morfologi spectra XRD, dan citra SEM-EDAX. Film tipis Barium Titanat (BaTiO3) murni dan BaTiO3 dengan variasi pendadah RuO2 2%, 4%, dan 6% yang ditumbuhkan pada silikon tipe-p (100) dengan metode Chemical Solution Deposition (CSD). Film BaTiO3 dan BaRuTiO5 dibuat dalam konsentrasi 2 M. Film tersebut ditumbuhkan dengan tiga kali pelapisan menggunakan teknik spin coating pada kecepatan putar 6000 rpm, 8000 rpm, dan 10000 rpm selama 30 detik. Film kemudian di annealing pada suhu 850 oC selama 8 jam. Film dikarakterisasi menggunakan spektrofotometer UV-Vis untuk mengetahui sifat optik berupa analisis nilai reflektansi, indeks bias dan energy gap. Metode ini memiliki keunggulan dapat mengontrol stokiometri film tipis dengan kualitas yang baik, prosedur yang mudah dan biaya yang relatif murah. Energi band gap berkisar 3.25 sampai 3.27 eV dengan indeks bias 2.7749894 sampai 2.77498944. Film tipis BaTiO3 memiliki parameter kisi a = 4.035 sampai 4.097 Ǻ dan c = 4.043 sampai 4.107 Ǻ serta ukuran kristal berada pada rentang 0.175 μm sampai 0.5 μm.
Keyword: film tipis, sifat optik, barium titanat, chemical solution deposition, pendadah, ruthenium oksida

Judul: Characterization of the crystal structure and optics of  BaTiO3 thin film in Ruthenium powder
Abstrak: Sintesis dan karakterisasi film tipis BaTiO3 dengan variasi konsentrasi pendadah Rutenium 0%; 0,5%; dan 1% telah berhasil dilakukan menggunakan metode Chemical Solution Deposition. Film BaTiO3 yang dibuat dalam konsentrasi 2M ditumbuhkan dengan teknik spin coating dalam lima kali pelapisan dengan kecepatan putar 3000 rpm selama 30 detik dan melalui proses annealing selama 8 jam pada suhu 850°C. Film tipis BaTiO3 dikarakterisasi dengan XRD, UV-Vis dan FTIR untuk menganalisis struktur kristal dan sifat optik sampel. Hasil karakterisasi XRD dengan metode Cramer- cohen dan software MAUD menunjukkan bahwa parameter kisi semakin berkurang dan struktur kristal tetap berbentuk tetragonal. Karakterisasi spektrofotometer UV-Vis menunjukan peningkatan nilai reflektansi pada rentang panjang gelombang 380 - 600 nm dengan peningkatan nilai energi bandgap dari analisis Kubelka-Munk untuk direct bandgap sebesar 2,41 eV, 3,37 eV dan 3,42 eV. Kemudian karakterisasi spektroskopi FTIR mengadopsi relasi Kramers-Kronig diperoleh indeks bias (n), koefisien extinction (k) dan parameter dielektrik bagian real (ε1) juga bagian imajiner (ε2) pada bilangan gelombang dengan penambahan pendadah Rutenium memperkecil medan listrik dan menyebabkan penurunan nilai moda optik TO dan LO yang memengaruhi konstanta optik sampel., Synthesis and characterization of BaTiO3 thin films with various concentrations of 0%; 0,5%; and 1% ruthenium scavenger has been successfully carried out using the Chemical Solution Deposition method. The BaTiO3 film prepared in a concentration of 2M was grown using the spin coating technique in five layers with a rotational speed of 3000 rpm for 30 seconds and annealed for 8 hours at 850°C. BaTiO3 thin films were characterized by XRD, UV-Vis and FTIR to analyze the crystal structure and optical properties of the samples. The results of the XRD characterization using the Cramer- Cohen method and MAUD software show that the lattice parameters decrease and the crystal structure remains tetragonal. Characterization of the UV-Vis spectrophotometer shows an increase in reflectance values in the wavelength range of 380-600 nm with an increase in the bandgap energy value from the Kubelka-Munk analysis for direct bandgap of 2,41 eV, 3,37 eV and 3,42 eV. Then the FTIR spectroscopic characterization adopts the Kramers-Kronig relation obtained refractive index (n), extinction coefficient (k) and the dielectric parameters of the real part (ε1) as well as imaginary part (ε2) in wave numbers with the addition of ruthenium divider reduce the electric field and causes a decrease in moda value optical TO and LO which affect the optical constant of the sample.
Keyword: BaTiO3, bilangan gelombang, CSD, energi bandgap, parameter kisi, bandgap energy, lattice parameters, wavenumber

Judul: Phylogeography and Species Limits in the Papuan White Snake (Micropechis ikaheka) (Reptilia: Serpentes: Elapidae)
Abstrak: Papua white snake, Micropechis ikaheka, has been distingushed into two subspecies M.i. ikaheka and M.i. fasciatus. However, due to lack of data on their morphology, distribution and ecology, both subspecies often ignored in scintific discussions and refers only byas , Micropechis ikaheka. This study was designed to document the differences between M.i. ikaheka and M.i fasciatus by using scales characteristics and reproductive organ or hemipenes. The study also examine, zoogeography, habitat, diet and cannibalism of both subspecies to better understanding the the ecology of one of the most venomous snakes in the world. This study consists of three topics with method and also different in the size samples, respectively. The first study is the histology and microtopography of the skin were studied using paraffin method and Scanning Electron Microscope (SEM). The second is the hemipenis were examined by following Myers and Cadle (2003), and Zaher and Prudente (2003). The third is the abdominal surgery was carried out to document diet type and the investigate phenomenon of cannibalism in the snake. Specimens for this study came from the collection from Museum Zoologicum Bogoriense (MZB) and Universitas Negeri Papua’s Laboratory (LZU). The research result also indicated that the markers of skin and hemipenis described the same structure and microornamentation in all M. ikaheka groups being compared. Based specimens examined morphological descriptions do not s support the further differentiation in Micropechis. In short, two markers that used in this study could not sufficiently indicate the differences in the level of species and subspecies of M. ikaheka. The study, however, were able to delineate zoogeography and skin color patterns, which fall into four groups: M. i. ikaheka; M. i. fasciatus. M. i. ssp. “intermediate”; and M. i. ssp “black”. This study also revealed that color variations did not overlap in their geographic distribution. It is therefore, it suggested that environmental factors may contribute to the skin color variations. It also assumed that habitat discontinuous and biogeography factors may also cause the loss of the connection between the original populations (vicarians) or follow colonization events (dispersal). The examined of 22 stomach contents of M. ikaheka shows this species is carnivorous, and prey on vertebrates such as amphibians, fish, reptiles, and Mammals. These snakes are opportunistic predators since they prey on all that can be captured, but mainly reptiles (61.5%), followed by mammals and fish (both 15.4%), and amphibians (7.7%). Although categorized as terrestrial animal, the diet study showed that M. ikaheka snakes often go into the water to hunt for fish (the sample from Yapen island), including eel (the sample from Aru island). Based on prey items indentified, there is evidence that M. ikaheka is cannibal. At this time, there still no record on reason for cannibalism, but it is assumed that cannibalism was due to competition between populations and means to control population.
Keyword: geographic variation, white snake, papua