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"Fourier transform infrared (FTIR) microspectrometry was used to characterize thin conducting films of poly[2 methoxy-5(2-ethylhexylox)-1,4] phenyelenevinylene (MEH-PPV)....."

"Pada penelitian ini dilakukan kajian pengembangan teknik deteksi ortofosfat dalam sistem akuatik yang dapat menyebabkan fenomena eutrofikasi. Sistem deteksi ortofosfat yang dipakai pada penelitian ini menggunakan sistem Diffusive Gradients in Thin Films DGT dengan lapisan pengikat berbasis biokomposit Fe-Loaded-Kitosan-Bentonit Fe-CSBent. Spesi fosfat berdifusi melalui lapisan difusi gel poliakrilamida kemudian diikat oleh agen pengikat biokomposit Fe-CSBent dalam lapisan pengikat gel poliakrilamida. Pengikatan fosfat oleh biokomposit Fe-CSBent melalui tiga mekanisme, yaitu interaksi elektrostatik, pembentukkan kompleks Lewis, dan pergantian ion ion-exchange. Pada penelitian ini diuji kemampuan DGT berbasis biokomposit Fe-CSBent dalam mengikat fosfat dengan variasi waktu, konsentrasi analit, pH, pengaruh sodium tripolyphosphate STPP sebagau anion pengganggu, dan aplikasi pada sistem akuatik. Massa fosfat yang terikat diketahui setelah dielusi dengan asam dan diukur kadar fosfatnya dengan metode fosfomolibdenum biru menggunakan spektrofotometri UV-Vis. Berdasarkan hasil percobaan, perangkat DGT berbasis biokomposit Fe-CSBent lebih efisien mengikat ortofosfat dengan konsentrasi fosfat yang terikat sebesar 2,2970 ? g/mL, dibandingkan dengan perangkat DGT berbasis biokomposit CSBent mengikat fosfat dengan konsentrasi sebesar 1,7333 ? g/mL. Berdasarkan penelitian ini juga diketahui bahwa keberadaan STPP mempengaruhi jumlah konsentrasi ortofosfat yang terikat pada gel pengikat berbasis biokomposit Fe-CSBent. Perangkat DGT berbasis biokomposit Fe-CSBent yang dibuat selektif dalam memprediksi jumlah fosfat yang bioavailabel, namun keberadaan spesi fosfat lain selain fosfat bebas yang diketahui berdasarkan percobaan gangguan sodium tripolyphosphate STPP dan secara ex situ dapat mempengaruhi pengikatan ortofosfat oleh DGT.

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In this work, a study of orthophosphate detection techniques in the aquatic system that causes eutrophication has been conducted. The orthophosphate adsorption technique used in this study was Diffusive Gradients in Thin Films DGT with Fe Loaded Chitosan Bentonite Fe CSBent biocomposite as binding agent. The phosphate diffuses through the polyacrylamide gel as diffusion layer and then bonded by a Fe CSBent biocomposite as binding agent in the polyacrylamide gel as binding layer. The mechanism of phosphate binding by Fe CSBent was governed by ion exchange, electrostatic attraction, and inner sphere complexation. In this experiment, we tested the Fe CSBent biocomposite based DGT capability in phosphate binding with influenced parameters such as agitation time, pH of the solution, initial phosphate concentration, presence of co existent anions i.e. sodium tripolyphosphate STPP, and application in aquatic systems. The phosphate mass can be calculated after eluting with acid and then measured by blue phosphomolybdenum method using UV Vis spectrophotometry. Based on the experiment, Fe CSBent biocomposite based DGT more efficiently binds orthophosphates with concentration is 2,2970 g mL, compared with a CSBent biocomposite based DGT with concentration is 1,7333 g mL. Based on this experiment, it was also known that the presence of STPP influences the amount of orthophosphate concentration binds to Fe CSBent biocomposite in binding gel. DGT Fe CSBent device which was made is selective in predicting bioavailable phosphate, but the presence of other phosphate species such as polyphosphate may influence orthophosphate binding by DGT."

"Sn/Se/Sn stacked layers were thermally deposited onto glass substrates at subsequent thicknesses of 150/300/150 nm, and were then annealed in a carbon block under running argon gas at 200 C for three hours to form stoichiometric SnSe thin films. The dark electrical resistivity measurements were made using van der pauw method on the samples heated up between 297-443 K. The resistivities of SnSe thin films were found to change with the sample temperature. Essentially, the resistivity decreased exponentially from 1.77 cm to 0.32 cm with an increase of temperature. The corresponding activation energies were 0.11 eV for the 297-373 K range and 0.17 eV for the 373-433 K temperature range, respectively "

"Thin film yang memiliki sifat PMA (Perpendicular Magnetic Anisotropy) memiliki arah momen magnet yang tegak lurus dengan permukaan film. Sifat ini memungkinkan thin film diaplikasikan dalam perpendicular magnetic recording yang digunakan sebagai penyimpanan data komputer. Maka dari itu, penting untuk mempelajari sifat magnetik dari thin film terutama mekanisme magnetization reversal. Pada penelitian ini akan dilihat hubungan antara mekanisme magnetization reversal pada thin film Co/Pt dan CoFeB/Pd dengan parameter  pada model Fatuzzo-Labrune. Jika magnetisasi kedua thin film dibalik dari kondisi tersaturasi sempurna, maka nilai  yang berarti mekanisme magnetization reversal akan didominasi oleh domain wall motion. Ketika magnetisasi kedua thin film dibalik dari kondisi tidak tersaturasi sempurna, maka nilai  akan berubah bergantung pada kondisi awal magnetisasi thin film. Kita akan melihat bahwa dari kedua kondisi yang berbeda, mekanisme magnetization reversal dapat dijelaskan dengan baik oleh model Fatuzzo-Labrune.

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Thin film with PMA (Perpendicular Magnetic Anisotropy) has magnetic moment perpendicular with its surface. This property allows thin film to be applied to perpendicular magnetic recording used in computer data storage. Therefore, it is important to study magnetic properties, especially magnetization reversal mechanism. In this study, we will see the correlation between magnetization reversal mechanism of Co/Pt and CoFeB/Pd thin films and  parameter on the Fatuzzo-Labrune model. If the magnetization reversal process of both films started from a fully saturated state, the value of  which means magnetization reversal mechanism will be dominated by domain wall motion. If the magnetization reversal process of both films is not started from a fully saturated state, the parameter  will change depends on the initial magnetization state. We will see that from two different conditions, magnetization reversal mechanism is well described by Fatuzzo-Labrune model."