Judul: Degradasi methylene blue dengan metode fotokatalisis dan fotoelektrokatalisis menggunakan film TiO2
Abstrak: Dengan metode squeegee printing, dapat dibuat lapisan semikonduktor TiO2 pada substrat Indium TinOxide. Hasil karakterisasi XRD menunjukkan bahwa film yang dihasilkan adalah anatase dengan nilai parameter kisi kristal a = b = 3.7945 dan c = 9.579, serta ukuran kristal adalah 24.545 nm. Pengaruh konsentrasi awal Methylene Blue, pH awal, pemberian potensial bias, dan penambahan H2O2 dievaluasi. Degradasi MB memperlihatkan hasil yang optimal pada konsentrasi awal MB 5 x 10-6 M, dan pada keadaan basa, yaitu pH 11. Pada keadaan basa, film TiO2 akan bermuatan negatif, dan karena MB merupakan dye kationik maka adsorbsi MB pada partikel TiO2 akan meningkat, sehingga degradasi MB juga akan meningkat. Adanya penambahan potensial bias eksternal dan H2O2 dapat meningkatkan degradasi MB karena kedua metode ini dapat menghalangi terjadi rekombinasi elektron dan hole. Kombinasi fotoelektrokatalisis dan penambahan H2O2 memperlihatkan hasil terbaik diikuti fotoelektrokatalisis, fotokatalisis+H2O2, fotolisis+ H2O2 dan fotokatalisis, dengan persen degradasi berturut-turut adalah 89.23%, 84.19%, 83.68%, 76.63%, dan 61.50%.
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Judul: Sintesis Fotokatalis Nanokomposit Fe2O3/Carbon-Dots dengan Metode Hidrotermal dan Iradiasi Microwave untuk Mendegradasi Methylene Blue
Abstrak: Fotokatalisis merupakan suatu metode yang efisien untuk mendegradasi senyawa organik menggunakan material semikonduktor sebagai fotokatalis. Fe2O3 disintesis dengan metode hidrotermal. Carbon dots (CDs) disintesis dari ekstrak kulit singkong dengan metode hidrotermal berbantuan microwave dengan panjang gelombang emisi 501 nm. Nanokomposit Fe2O3/CDs disintesis dengan metode iradiasi microwave. Struktur kristal, morfologi permukaan, komposisi kimia dan gugus fungsi berturut-turut dikarakterisasi menggunakan X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX) dan Fourier Transform Infrared (FTIR). Sifat optik CDs berupa absorbansi dan fluoresensi diamati dengan menggunakan spektroskopi UV-Vis. Penelitian ini bertujuan mengetahui efektivitas fotokatalis Fe2O3/CDs dalam mendegradasi Methylene Blue di bawah iradiasi cahaya tampak. Penggunaan fotokatalis Fe2O3/CDs terbukti meningkatkan efektivitas dan laju kinetik penurunan konsentrasi Methylene blue. Penambahan CDs meningkatkan laju degradasi larutan Methylene blue dengan fotokatalis Fe2O3/CDs di bawah iradiasi cahaya tampak, yakni sekitar 4.8 kali lipat dibandingkan dengan konstanta laju degradasi larutan Methylene blue tanpa fotokatalis yaitu sebesar 0.001 menit-1.
Keyword: carbon dot, fotokatalis, hidrotermal, iradiasi microwave, nanokomposit

Judul: Studies on growth spurt and aging in higher primates
Abstrak: single measurement that best defines the health and nutritional status of children, just as it provides an indirect measurement of the quality of life of an entire population. The pattern of human growth reflects the biocultural evolution of our species. The human pattern of growth and development (ontogeny) appears to differ markedly from patterns of ontogeny in other primate species. Three studies are reported here which deal to the growth and development of human and chimpanzee (Pan troglodytes). These three studies allow us to contrast the phenomena of adolescence growth spurt and female elderly bone loss in chimpanzee and human as chimpanzee is the closest species to humans within extant nonhuman primates. In the first, a cross-sectional study of growth of the body size and somatotype of 363 Javanese girls and 299 Javanese boys aged 4 to 20 years from Magelang Regency, Indonesia was described. In the second, cross-sectional and longitudinal studies in the growth of chimpanzee second metacarpal bone linear dimensions from individuals aged 0 to 43.6 years were used for comparison. While in the third, cross-sectional and longitudinal studies in the growth of chimpanzee body size (body mass and anterior trunk length) and second metacarpal bone mineral content were derived. In measuring the second metacarpal dimensions and mineral content, a total of 568 radiographs of chimpanzee's proximodistal left hands were used. They were taken from 68 females and 49 males aged 0 to 43.62 years old. We applied an image analysis system, Scion Image Release Alpha 4.0.3.2 software for Windows to measure bone linear dimensions and bone mineral content. Humans present complex and sinuous growth curves for both body weight and height. A clear growth spurt could be demonstrated by cross-sectional analysis in our girl subjects at around aged 11.5 years and in our boy subjects at around aged 12.5 years. In longitudinal series, not in cross-sectional, several representative chimpanzees of both sexes showed a pre-adult growth spurt on the body sizes, bone dimensions and bone mineral content. They ranged at age 4.5 to 8.5 years. This underscore the fact that adolescent growth spurt in linear dimension was not a universal feature of anthropoid primate ontogeny. Bone loss is a well established characteristic of human female aging. Based on crosssectional analyses the sequential decline of bone mass in female chimpanzee may be said to be genuine. On the other hand, we found in adulthood through elderly, male chimpanzees show a longer plateau than female chimpanzee, that is, bone mineral content is maintained in male.
Keyword: Javanese children, growth spurt, chimpanzee, second metacarpal bone, bone loss, Higher Primates