Judul: Application of phycocyanin from microalgae Spirulina platensis as light harvesting in anatase TiO2 nanoparticle solar cell.
Abstrak: The dye sensitized solar cell (DSSC) has been assemblied used hybrid titanium oxide (TiO2) film/phycocyanin. The TiO2 film was synthesized by sol gel method with titanium chlorida (TiCl4) as precursor by hydrolysis used sulfuric acid (H2SO4). Furthermore, it calcinated for 2,5 hours in variation of annealing temperature (400oC, 600oC, 800oC, dan 1000oC). In XRD patterns exhibited which annealing temperature at 400oC to 800oC were anatase phase all. When annealed at temperature 1000oC, it caused phase transformation from anatase to rutile. The crystals size according to XRD patterns were 13,75 nm, 20,79 nm, 25,25 nm, 48,88 nm and particle size from SEM images were 43,06 nm, 44,91 nm dan 64,99 nm, 80,40 nm, respectively. The crystals and particle size increased with annealing temperature. The film thickness influenced material absorption. The optical measurement of TiO2 film and TiO2/phycocyanin hybrid film used UV-Vis spectrophotometer. Additional phycocyanin caused peak width of absorbed region from ultraviolet to visible region. The band gap energy of TiO2 can be calculated using the cut off wavelength obtained from the absorbance spectrum of a nanoparticles TiO2 films. Based on intersection between linear and energy (hv) axis. In this study just limited for anatase phase. It was caused anatase band gap is wider than rutile phase. That’s meaningful for solar cell application such as dye sensitized solar cell (DSSC). The absorption coefficient average at difference annealing temperature such as at 400oC, 600oC, 800oC were 8,1600x102, 1,7535x103 and 4,0154x102, where α < 104 include to direct transition. Band gap energy 400oC, 600oC, 800oC were 3,79 eV, 3,59 eV, and 3,35 eV, respectively. Based on this result, exhibition that band gap energy of TiO2 semiconductor film decreased with increasing annealing temperature. Spirulina platensis was cultivated in technical modification (Hastuti) with aeration under light intensity about 3000 lux. The cell density (stationer phase) for eighth day which OD value was more than 0,5. It means, the culture can be harvested. In 80 liters Spirulina platensis culture have been produced biomass dry about 10,46 gram and extracted phycocyanin in dry powders was 5,50 gram. The phycocyanin absorption spectrum at the wavelength of 619,36 nm (visible region) which had relaxation energy was 2,945 eV. The emission peak at the wavelength of 708,55 nm with relaxation energy about 2,793 eV. The Stokes shift based on difference energy absorption and emission calculated about 0,152 eV. Both of this showed phycocyanin can absorbed and radiated the sun light which received. This choice characteristic pigment was a good one related to sensitizer in solar cell application. Integration between light harvesting protein and TiO2 semiconductor surface had important role in improving of output as solar cell materials. The presence of carboxylate group (-COOH) made pigment be more efficient was due to anchored to the surface of TiO2 ampoter. The phycocyanin pigment had carboxylate group which reacted with TiO2 surface formed ester. The carboxylate group increased of dye electronics couple from excited state (p anti bonding orbital) to semiconductor acceptor state (TiO2 conduction band). The samples which made based on annealing temperature variation formed be solar cell respectively. Furthermore, cells be assembled for
Keyword: anatase, dye sensitized solar cell, efficiency, gap energy, phycocyanin

Judul: Study Literature of Potential of Parijoto Extract and Tapak Dara Leaf as Photosensitizer in Dye Sensitized Solar Cell
Abstrak: Ketersediaan energi fosil semakin menipis sehingga diperlukan solusi untuk mengatasinya, yaitu dengan sel surya generasi ketiga yang menggunakan bahan organik, dikenal sebagai dye sensitized solar cell (DSSC). DSSC terdiri atas elektrode kerja, larutan elektrolit, elektrode lawan, dan pemekacahaya. Pemekacahaya menjadi komponen penting pada DSSC karena berfungsi menyerap energi cahaya pada panjang gelombang tertentu sehingga banyak dikembangkan untuk DSSC karena lebih ramah lingkungan dan ketersediaan yang melimpah. Antosianin dan alkaloid dapat digunakan pada DSSC sebagai pemekacahaya alami. Dalam kajian ini dijelaskan potensi ekstrak buah parijoto (Medinilla speciosa) dan daun tapak dara (Catharanthus roseus L.) sebagai pemekacahaya serta energi yang menyertai pada permukaan TiO2 sebagai fotoanode pada DSSC. Hasilnya menunjukkan bahwa antosianin dapat digunakan sebagai pemekacahaya pada DSSC meskipun memiliki nilai efisiensi yang masih rendah. Selain itu, alkaloid diperkirakan berpotensi sebagai pemekacahaya, penggunaan kedua golongan senyawa alami tersebut diharapkan mampu meningkatkan kinerja DSSC. Kata kunci: alkaloid, antosianin, DSSC, pemekacahaya, The availability of fossil energy is running low, so a solution is required to resolve this. The solution is to utilize third-generation solar cells that use organic materials, known as dye-sensitized solar cells (DSSC). The DSSC consists of a working electrode, electrolyte, counter electrode, and photosensitizer. The photosensitizer is an essential component in DSSC because it plays an essential role in absorbing light energy at a specific wavelength. Natural photosensitizers have been developed for DSSC because they are more environmentally friendly and have abundant availability. Anthocyanins and alkaloids can be used in DSSC as natural photosensitizers. The review describes the potential of parijoto fruit (Medinilla speciosa) and tapak dara (Catharanthus roseus L.) leaf extracts as a photosensitizer and the energy on the surface of TiO2 as a photoanode in the DSSC. The results showed that anthocyanin could be used as photosensitizers in DSSC despite the low efficiency. In addition, alkaloids estimated potential used as photosensitizers. These two sensitizers are expected to improve the DSSC performance. Keywords: alkaloid, anthocyanin, DSSC, photosensitizer
Keyword: alkaloid, anthocyanin, DSSC, photosensitizer

Judul: Prolapsus vagina kronis, kausa dan teknik reposisinya
Abstrak: Prolapsus vagina kronis merupakan penyembulan bagian belakang hewan, khususnya lantai vagina melalui vulva, diikuti dengan perpindahan serviks dan uterus ke belakang. Pada sapi kejadian prolapsus vagina sering pada masa 2-3 bulan akhir kebuntingan, sedangkan pada domba dan hewan sejenisnya terjadi beberapa minggu sebelum melahirkan. Kasus prolapsus vagina kadang-kadang dapat terjadi setelah melahirkan, dan jarang terjadi tanpa ada hubungannya dengan kebuntingan atau kelahiran. Penyebab prolapsus vagina kronis belum dapat dipastikan, beberapa faktor umumnya ambil bagian. Faktor uta- ma adalah tingginya kadar hormon estrogen pada akhir kebuntingan. Faktor mekanis dengan meningkatnya tekanan intra abdominal dan gaya berat dari fetus dalam kandungan. Beberapa faktor predisposisi yang dapat menunjang terjadinya prolapsus vagina adalah: perlukaan saluran kelahiran, kelahiran yang rapat, makanan yang kurang baik, terbatasnya pergerakan, faktor lingkungan dan hereditas. Prolapsus vagina kronis umumnya hampir terjadi pada semua hewan piara, lebih sering pada sapi dan domba. Pada sapi sering terjadi pada sapi potong jenis Hereford ...
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