Judul: Kinerja Dye Sensitized Solar Cell Berbahan Dasar Polistirena Tersulfonasi dan Pewarna Sari Alami Beta vulgaris L.
Abstrak: Dye Sensitized Solar Cell (DSSC) adalah perangkat sel surya generasi ketiga yang mampu mengkonversi energi cahaya menjadi energi listrik dengan bantuan zat warna. Pewarna yang digunakan pada penelitian ini adalah sari alami umbi bit merah yang didapatkan dari proses tanpa maserasi. Rangkaian DSSC terdiri atas elektrode kerja, zat warna, elektrolit, dan elektrode lawan. Larutan elektrolit yang umum digunakan adalah I-/I3- namun elektrolit ini mempunyai kelemahan mudah menguap sehingga dapat menurunkan nilai efisiensi DSSC. Penelitian ini bertujuan mengetahui penggunaan sari alami umbi bit merah (Beta vulgaris L.) sebagai zat warna pada sistem DSSC, pengaruh penambahan polistirena tersulfonasi disebabkan potensinya sebagai elektrolit DSSC dengan dua perlakuan berbeda, yaitu pencampuran dan perendaman pewarna terhadap TiO2 yang mempengaruhi nilai efisiensi kinerja DSSC. Nilai efisiensi DSSC dengan perlakuan pencampuran dan penambahan PSS menghasilkan efisiensi tertinggi sebesar 1,74%. Teknik pewarnaan terhadap PSS melalui proses pencampuran memperoleh efisiensi kinerja lebih baik dibandingkan dengan proses perendaman yang didapatkan perbedaan efisiensi senilai 36%., Dye Sensitized Solar Cell (DSSC) is a third-generation solar cell device capable of converting light energy into electrical energy with the help of dyes. The dye used in this study was the natural of beetroot obtained from the process without maceration. The DSSC circuit consists of a working electrode, a dye, an electrolyte, and an opposing electrode. The electrolyte solution commonly used is I-/I3- but this electrolyte has the disadvantage of being volatile so that it can reduce the efficiency value DSSC. This study aims to determine the use of natural juice of red beet tubers (Beta vulgaris L.) as dyes in the DSSC system, the effect of adding sulfonated polystyrene due to its potential as a DSSC electrolyte with two different treatments, namely mixing and soaking dyes against TiO2 which affects the efficiency value of DSSC performance. The efficiency value of DSSC with PSS mixing and addition treatment resulted in the highest efficiency of 1,74%. The staining technique for PSS through the mixing process obtained better performance efficiency compared to the soaking process which obtained a difference efficiency of 36%.
Keyword: beetroot, DSSC, efficiency, polystyrene sulfonated

Judul: Kajian Pustaka Kinerja Dye Sensitized Solar Cell-Polistirena Tersulfonasi-α-Fe2O3 dengan Pemeka Klorofil Daun Pepaya
Abstrak: Dye sensitized solar cells (DSSC) merupakan sel surya generasi ketiga untuk konversi energi cahaya menjadi energi listrik dengan biaya yang cukup rendah serta ramah lingkungan. Zat pemeka yang digunakan berupa klorofil daun pepaya dengan cincin porfirin yang mampu mentransfer elektron. Semikonduktor yang digunakan adalah hematit (α-Fe2O3) dengan sela pita yang cukup kecil dan kristalinitas yang baik sehingga mampu mempercepat proses transfer elektron. Polistirena tersulfonasi (PSS) merupakan polimer membran elektrolit dengan ketahanan termal tinggi yang dapat mengatasi kekurangan dari elektrolit iodida/triiodida (I-/I3-). Penelitian ini bertujuan mengkaji kinerja DSSC termodifikasi polimer elektrolit polistirena tersulfonasi dan semikonduktor α-Fe2O3 dengan zat pemeka berupa pigmen klorofil dari daun pepaya. Klorofil dari daun pepaya cukup potensial digunakan sebagai pemeka DSSC karena memiliki kadar klorofil cukup tinggi (29,6 mg/g). Tambahan PSS mampu meningkatkan efisiensi kinerja lebih dari 100%. Namun, aplikasi α-Fe2O3 sebagai semikonduktor DSSC masih rendah sehingga perlu dikembangkan lebih lanjut., Dye-sensitized solar cells (DSSC) are the third-generation solar cell for the conversion of light energy into electrical energy at a fairly low cost and environmentally friendly. The dye used was chlorophyll of papaya leaves with porphyrin rings that are capable of transferring electrons. The semiconductor used was hematite (α-Fe2O3) with a fairly small gap band and good crystallinity to speed up the electron transfer process. Sulfonated polystyrene (PSS) is a high thermal resistance electrolyte membrane polymer that can overcome the deficiency of iodide electrolyte solution/triiodide (I-/I3-). This study aims to examine the performance of the DSSC-modified sulfonated polystyrene α-Fe2O3 with dyes derived from papaya leave chlorophyll. The papaya leave is quite potential to be used as a DSSC dye due to its chlorophyll content as high as 29.6 mg/g. The PSS addition increases the efficiency by more than 100%. However, the α-Fe2O3 application as a DSSC semiconductor is low, therefore, further development is required.
Keyword: daun pepaya, DSSC, hematit, klorofil, polistirena tersulfonasi

Judul: Analisis Model Pandemik dan Prepandemik Avian Influenza pada Populasi Manusia
Abstrak: Avian influenza is a viral disease caused by a virus within the subtype of H5N1 in which its transmission caused by birds or human. In human population, transmission process of avian influenza is discussed in the model called: bird model, prepandemic model and pandemic model. The bird model has two equlibrium points. These are saddle disease free equilibrium and stable endemic equilibrium. The endemic equlibrium occurred when the reproduction number of avian influenza is greater than one. In the endemic equilibrium, avian influenza may infect both bird and human. The prepandemic model has two equilibrium points. These are avian influenza dominant equilibrium and human influenza dominant equilibrium. The human influenza dominant equilibrium occurred when the reproduction number of human influenza is greater than one. The pandemic model has one pandemic equlibrium. The human influenza pandemic occurred when the ratio of human influenza invasion, pandemic invasion and the reproduction number of human influenza is greater than one, respectively. The avian influenza pandemic occurred when the ratio of human influenza invasion, pandemic invasion is less than one and the reproduction number of avian influenza greater than one, respectively.
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