Judul: Kajian teknik elektrokoagulasi untuk pemisahan mikroalga
Abstrak: Although microalgae can grow fast in liquid wastes, there was no efficient technique yet for remove them. An electro-coagulation technique was examined to remove microalgae from the liquid wastes. For the batch system electro-coagulation process used in this experiments two aluminum electrode. This type of metal selected because it could introduce the coagulation agent into the liquid, there by microalgae could be removed. The used wastes are wastewater from animal husbandry and synthetic wastewater. The experiment was done by batch method used 1 Liter microalgae for each treatment on direct current variated from 9, 12 and 15 Volt and operation time from 10 to 40 minutes. The result of treatment were remarkably good and the efficiencies to total suspended solid (TSS) as the amount of microalgae removed reached to 51,55% for husbandry wastewater and 28,98% for synthetic on the direct current of 15 Volt and operation time 40 minutes. Beside can removed microalgae from wastewater electro-coagulation give effect for the other parameters of the wastewater like turbidity, color, concentration of COD, concentration of phosphate and pH value. The reduction of those parameters value reached along with the raising direct current voltage and operating time.
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Judul: Karakterisasi Pertumbuhan Mikroalga dan Eliminasi Nutrien dari Limbah Cair Peternakan dengan Sistem Semi Kontinu
Abstrak: One way of wastewater treatment is a biological process with the help of a combination of microorganism such as bacteria and microalgae. Degradation organic content of waste water by bacteria and then the result of degradation by bacteria in the form of nitrate and CO2 utilized by microalgae. Microalgae also produce O2 as a result of photosynthetic bacteria that can be used. The growth of microalgae is very closely related to the availability of macro and micro nutrients as well as influenced by environmental conditions. Microalgae needed nutrients consist of macro nutrients (N, P, K, S, Fe, Mg, Si and Ca) and micro nutrients (Mn, Zn, Co, Bo, Mo, B, Cu, etc. ). Environmental factors that influence the growth of microalgae, including light, temperature, water pH, and salinity. The purpose of this research to know microalgae growth caracterization in wastewater cattle breeding and to know nutrient eliminate caracterization from wastewater cattle breeding on microalgae cultivation with semi-continuous system. In this research, microalgae was cultivated, using microalgae inoculum from Lake LSI IPB and use wastewater of cattle breeding from MT Farm Ciampea. Pretreatment wastewater used aerator in a tank for five weeks. The purpose of this pretreatment to reduce odor generated liquid waste and reduce organic matter content. In a preliminary study done by two microalgae cultivation treatments on the vessel I (75% wastewater: 25% inoculum microalgae) and the vessel II (50% wastewater: 50% inoculum microalgae). Techniques of microalgae culture has done semi continuous. Harvesting was conducted periodically, and the addition of nutrients to the volume culture as much as the amount have harvested. Of the two treatment obtained a preliminary study of the best cultivation method is in the vessel I, where the abundance of microalgae were compared with the second vessel. At the main study by using waste ratio 75%: 25% visible microalgae abundance of microalgae in the early experiments of H-12 and the harvesting of 25% with semi-continuous system, and the H-16 was again semi-continuous harvesting system as well as 75%. From this treatment more quickly visible growth after harvesting microalgae microalgae as much as 75%, because the waste was added too many (75% = proportional to that harvested). In the first experiment with detention time of 12 days nitrogen concentration was decreased 5.79%, orthophosphate concentration was decreased 0.34%, and COD concentration was decreased 75%. In the second experiment with two days detention time nitrogen concentration was decreased 0.63%, orthophosphate concentration was decreased 0.15%, and COD concentration was decreased 33%. In the third experiment with detention time of 6 days the nitrogen concentration was decreased 3.14%, orthophosphate concentration was decreased 0.42%, and COD concentration was decreased 78%. Harvesting with the test results of TSS in H-12 abundance of microalgae in 2135 mg / L. Microalgae are good for handling wastewater has a high nutrient content. In addition nutrient content that have contained in mediakultivasi, light, temperature and pH are important factors also in microalgae cultivation. To enhance the ability of microalgae to eliminate the nutrient contained in the wastewater, waste volume ratio must be greater than the volume of microalgae.
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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