Judul: Kinetic Analysis of Mixing Coagulants and Floculants for White Water Paper Industry Wastewater Treatment
Abstrak: Upaya meningkatkan efisiensi penurunan parameter total solid (TS), turbiditas, dan COD dilakukan dengan memanfaatkan proses koagulasi-flokulasi untuk pengolahan air limbah industri kertas berjenis white water. Kombinasi koagulan yang digunakan yaitu alum, poliamin, serta flokulan anionik poliakrilamida. Analisis kinetika pada mekanisme koagulasi-flokulasi dilakukan dengan persamaan laju reaksi orde satu, dua, dan tiga. Selain analisis kinetika, hasil eksperimen dibandingkan dengan model prediksi Gompertz untuk melihat potensi kesesuaian antara data eksperimen dan prediksi serta melihat proses adsorpsi berdasarkan model isoterm adsorpsi (Langmuir, Freundlich, dan Temkin). Proses koagulasi dan flokulasi dapat menurunkan konsentrasi polutan maksimum untuk TS, kekeruhan, dan COD berturut-turut 84%, 99%, dan 17%. Pada penelitian ini, persamaan laju reaksi orde tiga menunjukkan hasil yang paling sesuai dengan mekanisme koagulasi-flokulasi. Prediksi berdasarkan model Gompertz menghasilkan data yang baik pada eksperimen menggunakan koagulan tunggal. Analisis adsorpsi membuktikan koagulan PA memiliki kapasitas adsorpsi yang baik pada ketiga model isoterm.
Keyword: flokulasi, isoterm adsorpsi, koagulasi, kinetika, pemodelan

Judul: Determination of Sedimentation Unit Design Parameters Based on the Settling Type Model of Coagulation-Flocculation Process Results in Paper Industry Wastewater
Abstrak: Teknologi pengolahan koagulasi-flokulasi merupakan opsi teknologi yang sering digunakan untuk pengolahan limbah kertas. Unit koagulasi dan flokulasi membutuhkan unit sedimentasi untuk mengendapkan flok berupa padatan tersuspensi dan material organik. Parameter yang diamati pada penelitian ini adalah Total Solid (TS) dan Chemical Oxygen Demand (COD). Dalam perancangan unit sedimentasi, empat tipe pengendapan digunakan untuk analisis sedimentasi, yakni tipe discrete settling, tipe flocculant settling, tipe hindered settling, dan tipe compression settling. Analisis empat tipe pengendapan akan menghasilkan parameter desain unit sedimentasi seperti surface overflow rate (SOR), kecepatan pengendapan, solid loading rate dan waktu detensi. Pada hasil analisis, nilai efisiensi penyisihan partikel TS pada setiap sampel berkisar antara 35-80%. Nilai SOR pada bak pengendapan diketahui berkisar antara 3-11 m3/m2∙hari. Kecepatan pengendapan berkisar antara 0,002-0,006 m/menit dan waktu detensi menghasilkan nilai sebesar 22-69 menit. Nilai parameter tersebut kemudian akan dianalisis menjadi nilai dimensi unit sedimentasi berdasarkan sampel yang memiliki nilai penyisihan TS paling besar., The coagulation-flocculation treatment is a technology that often used for paper and pulp wastewater treatment. The coagulation and flocculation unit requires a sedimentation unit to precipitate the floc in form of suspended solids and organic matter. Observed parameters in this study were Total Solid (TS) and Chemical Oxygen Demand (COD). It is necessary to analyze the four types of sedimentation, such as discrete settling, flocculant settling, hindered settling, and compression settling. The analysis of settling types will be resulting in parameters of the sedimentation unit design such as surface overflow rate, settling velocity, solid loading rate and detention time. In the analysis results, it is known that the efficiency of TS particle removal in each sample ranges from 35-80%. For the surface overflow rate in the settling basin ranges from 3-11 m3 /m2 ∙day. Settling velocity values ranged from 0,002-0,006 m/min and detention time parameter produces a value of 22-69 minutes. These parameter values will be analyzed into the design values in form of sedimentation unit design based on the sample with the largest TS removal value.
Keyword: coagulation, flocculation, particle, sedimentation, settling

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