Judul: DFT/TDDFT Study of Electronic and Optical Properties of Modified Black Tea Waste Pigment as Solar Cell Sensitizer
Abstrak: Dye sensitized solar cell (DSSC) pertama kali dikenalkan oleh Regan dan Gratzel. Salah satu bagian DSSC yaitu fotoanoda yang berisikan pewarna alami dan semikonduktor TiO2. Pewarna alami terbaru berasal dari limbah teh hitam yang didominasi pigmen theaflavin. Problematika saat ini rendahnya efisiensi DSSC alami daripada sintetis. Untuk meningkatkan efisiensi dengan menambahkan molekul donor dan bridge thiophene. Tujuan penelitian menganalisis pengaruh jumlah bridge thiophene dan perbedaan gugus donor pada pigmen warna limbah teh hitam terhadap sifat elektronik dan optik DSSC. Metode yang digunakan berbasis teori dan komputasi dengan pendekatan DFT dan TDDFT. Hasil penelitian menyimpulkan bahwa penambahan bridge thiophene pada dye theaflavin dapat memperbaiki dan meningkatkan sifat elektronik dan optik dari DSSC. Molekul donor yang lebih signifikan untuk meningkatkan parameter-parameter natural DSSC yaitu amina.
Keyword: DFT dan TDDFT, DSSC, Sifat elektronik dan optik, Theaflavin, Thiophene, Molekul Donor

Judul: Performance of Dye Sensitized Solar Cell Based on Sulfonated Polystyrene and Natural Dye Butterfly Pea Flower
Abstrak: Dye Sensitized Solar Cell (DSSC) adalah seperangkat sel surya yang berbasis fotoelektrokomia yang melibatkan transfer muatan listrik dari suatu fase ke fase lain Pewarna yang digunakan pada penelitian ini adalah sari alami bunga telang yang didapatkan dari proses tanpa maserasi. DSSC terdiri atas elektrode kerja, pewarna, 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 bunga telang 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 memengaruhi nilai efisiensi kinerja DSSC. Nilai efisiensi DSSC dengan perlakuan pencampuran dan penambahan PSS menghasilkan efisiensi tertinggi sebesar 1,56%. Teknik pewarnaan terhadap PSS melalui proses pencampuran memperoleh efisiensi kinerja lebih baik dibandingkan dengan proses perendaman., Dye Sensitized Solar Cell (DSSC) is a set of solar cells based on photoelectrochemistry which involves the transfer of electrical charge from one phase to another. The dye used in this research is the natural essence of butterfly pea flowers obtained from a process without maceration. DSSC consists of a working electrode, dye, and counter electrode. The electrolyte solution that is commonly used is I- /I3 - , but this electrolyte has the weakness of being volatile so that it can reduce the efficiency value DSSC. This study aims to determine the use of natural butterfly pea flower 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 1.56%. The staining technique for PSS through the mixing process obtained better performance efficiency compared to the soaking process.
Keyword: bunga telang, DSSC, efisiensi, polistirena tersulfonasi

Judul: Distribution and Diversity of Ectoparasite Mites on Geckos in Indonesia
Abstrak: Data on the diversity and dispersal of parasitic mites on house geckos in Indonesia are very scarce. In this work, the distribution and diversity of mites living on three species of house geckos, namely Cosymbotus platyurus, Hemidactylus frenatus, and H. garnotii collected throughout Indonesia, has been elaborated. Geckos and mites were captured and immediately preserved in 70% ethanol. Whole mount of the mites was prepared by clearing in lactophenol followed by mounting on polyvinyl lactophenol solutions. The SEM preparation was conducted to examine the detail morphological characters of the mites. The results showed that among 448 individuals of geckos, 221 geckos were infected by Geckobia mites. Prevalences of C. platyurus, H. frenatus, and H. garnotii infested by mites were 14.8%, 50.69%, and 79.6%, respectively. Three different spesies of Geckobia (G1, G2, and G3) could be differentiated; and based on similarities of their morphological characters to ones described in published literatures, Geckobia G2 is Geckobia glebosum and Geckobia G3 is Geckobia bataviensis while G1 could not be identified to the species level. The highest mean intensity of Geckobia G1 infestation was found on H. garnotii (I=7.0), G. glebosum infestation on H. frenatus (I=3.5), and G. bataviensis infestation on H. garnotii (I=11.8). In general, C. platyurus was infested by the least number of mites. Geckobia G1 were found living on the skin folds on the claws, G. glebosum were found mainly on the body and thigh, and G. bataviensis were found on almost all parts of the host’s body. Geckobia mites are distributed randomly throughout Indonesian Archipelago, following the pattern of distribution of their hosts. So it is concluded that Geckobia G1, G. glebosum, and G. bataviensis are sympatric.
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