Judul: Carbohydrate, protein and lipid production of microalgae in a raceway pond system: use of fertilizer combinations of ZA-NaNO3 and SP36-K2HPO4as N and P nutrient source
Abstrak: Microalgae is a photosyinthetic unicellular microbe which able to convert sunlight, water, carbon dioxide and nutrients to biomass. Since its biomass contains high grade of carbohydrate and lipid, microalgae is a potential source of biofuel. The objectives of this research were to identify 4 selected microalgae strains, to determine the optimum combination of technical grade ZA-NaNO 3 and SP36-K2HPO4 as the N and P nutrient source for cultivation of the strains at laboratory scale, and to evaluate the effects of the optimum combination of the N and P nutrient source on carbohydrate, protein and lipid production of each strain at field scale in a raceway pond system. The results showed that microalgae ICBB 9111 strain is Synechococcus sp., while ICBB 9112, ICBB 9113, and ICBB 9114 are Chlamydomonas sp. The highest carbohydrate was produced by Synechococcus sp. ICBB 9111 (43.90 % dry weight, DW) at 50 % ZA, 50 % NaNO3 and 100 % SP36, 0% K2HPO4 treatment. The highest protein was produced by Chlamydomonas sp. ICBB 9114 (29.09 % DW) at 50 % ZA, 50 % NaNO3 and 100 % SP36, 0 % K2HPO4 treatment. The highest lipid was produced by Chlamydomonas sp. ICBB 9113 (32 % DW) at 50 % ZA, 50% NaNO3 and 50 % SP36, 50% K2HPO4treatment.
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Judul: Seleksi dan karakterisasi ganggang mikro indigen air tawar sebagai penghasil karbohidrat untuk energi terbarukan
Abstrak: The objective of this research is to explore and isolate indigenous micro algae that have a high carbohydrate producer as potentially for bioethanol production. The exploration from indigenous fresh water fifteen micro algae carried out in a BG 11 media and resulted four different types of micro algae such as ICBB-CC (9111, 9112, 9114 and 6354 PLB). By morpholgical identification, they were identified as Crucigenia quadrata, Scenedesmus bijuga, Chlorella vulgaris, and Chlorella vulgaris respectively. They were cultivated in a 5 L reactor using three types media of BG 11, MBM and PHM. The fastest growing isolate was ICBB 9111 of C. quadrata in MBM medium. The production biomassa of four isolates were developed in the raceway of 90-100L using MBM modifications medium with TSP aims , because of media has a value of optical density (OD) which increased from 0.09 to 0,200 within 3 (three) days. Harvesting is done from the OD value ≥ 0.6 continuously and harvesting stopped at OD values ≤ 0.5. Harvesting by means of filtration and drying naturally at room temperature. Temperature micro algae in ponds ranging channel 30-35 oC and maintained volume in such a way as early cultivation (by adding water to take advantage of existing nutrients). Production of dried-biomass/L/d and the results of the proximate analysis of carbohydrates into four isolates : Crucigenia quadrata ICBB 9111, Scenedesmus bijuga ICBB 9112, Chlorella vulgaris ICBB 9114 and Chlorella vulgaris PLB 6354) is 0,038 (42.27% dry weight), 0,035 (21.30% dry weight), 0.019 (16.66% dry weight) and 0,018 (17.22% dry weight). Production of dry biomass / L / day and the results of the proximate analysis of carbohydrates into four isolates ICBB-CC (9111, 9112, 9114 and 6354 PLB) is 0,038 (42.27% dry weight), 0,035 (21.30% dry weight), 0.019 (16.66% dry weight) and 0,018 (17.22% dry weight). Result of the selection of four types of micro algae ICBB-CC (9111, 9112, 9114 and 6354 PLB,) with modifications MBM TSP aims to get local micro algae isolates that have high carbohydrate content potentially for the production of ethanol.Optimal conditions for hydrolysis process 48 hours using a commercial enzyme that includes two stages: liquefaction process using enzymes α-amylase 600U at 95 ° C with a pH of 6 while for the saccharification process using enzymes amiloglukosidase 145U at a temperature of 60 ° C, pH 4.5 and 120 rpm rotation .Ethanol content of 40-hour fermented using S. Cerevisiae each sample, namely: 9111 amounted to 50.47 ppm, 105.86 ppm for 9112, 9114 amounted to 53.38 ppm and 41.17 ppm of PLB 6354.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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