Makara Journal of Science
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KAOLIN SEBAGAI SUMBER SiO2 UNTUK PEMBUATAN KATALIS Ni/SiO2: KARAKTERISASI DAN UJI KATALIS PADA HIDROGENASI BENZENA MENJADI SIKLOHEKSANA
No full textKaolin as a SiO2 Source for Ni/SiO2 Catalyst Syntheses: Characterization and Application of Catalyst for Hydrogenation Benzene to Cyclohexane. Kaolin one of clay minerals has been employed as a SiO2 source and produced a mixture of two type SiO2, quartz and quartz alpha, with the amount of 60 % of kaolin used. The SiO2 produced had been diverted to silica gel and used as supporting agent for Ni/SiO2 catalyst through impregnation of Ni(NO3)2 solution to form Ka and Kb catalysts, that having surface area smaller than the silica gel. The pore size and volume of Ka catalyst is bigger than Kb catalyst. Catalytic properties of Ni/SiO2 catalysts have been investigated for benzene hydrogenation and resulting Ka catalyst had produced more cyclohexane than Kb catalyst. Keywords: kaolin, silica gel, Ni/SiO2 catalyst, benzene hydrogenation, cyclohexan
PENGARUH MUSIM TERHADAP FLUKTUASI KADAR FOSFAT DAN NITRAT DI LAUT BANDA
No full textThe Influence of Season to Nitrate and Phosphate Content Eutrophication in Banda Sea. Observation on phosphate and nitrate nutrient content were carried out in May, August, November, 1996 and February 1997 in Banda Sea. The results showed the averages content of phosphate and nitrate in August is higher compared to May, November and February. Phosphate content in August 1.492 g.at/l, while in May, November and February are 1.025 g.at/l, 0.878g.at/l and 0.766 g.at/l. Nitrate content in August is 1.932 g.at/l, while in May, November and February are 0.975g.at/l, 0.804 g.at/l and 0.670 g.at/l respectively. This result fixed with statistical Analysis (Randomized Block Anova) (Fh > F t 1%). This condition is caused by upwelling process in Banda Sea at that time.Keywords: Banda sea, phosphate, nitrate, upwellin
SENYAWA TRITERPENOID DARI EKSTRAK N-HEKSANA KULIT BATANG TANAMAN Garcinia benthami
No full textTriterpenoids compounds from N-hexane extract of the stem bark of Garcinia benthami. Two triperpenoids compounds, i.e. friedelin (1) and 3β-hydroxy-lanosta-9(11),24-dien-26-oic acid (2) were isolated from the n-hexane extract of the stem bark of Garcinia benthami. The structures of these compounds were elucidated by IR, MS,1H-NMR and 13C-NMR spectroscopy and by comparison of their spectroscopic data with those reported data from the literature. Keywords: Garcinia benthami, and triterpenoid  
SUKSESI MIKROBA DAN ASPEK BIOKIMIAWI FERMENTASI MANDAI DENGAN KADAR GARAM RENDAH
No full textMicrobial succession and biochemical aspects of mandai fermentation at low salt concentration. Mandai is fermented food that traditionally made from the flesh of jack fruit (Arthocarphus champeden Spreg.). Usually mandai is made as high salt concentration. However, the objective of this research is to study the succession and biochemical aspects of microbials during fermentation at low salt concentration (10% w/v) for 14 days. During the period of fermentation microbial cell numbers and biochemical aspects were observed at the 3rd, 5th, 7th and 14th day. Total cell number of bacteria and yeast were measured by pour plate method. The measurement was also conducted on flesh before incubation. The biochemical aspect observation included the contents of reducing sugar, N-total, salt, and pH. The research results indicated that the pattern of microbial succession occurred the fermentation. Yeast cells grew dominantly (2.8 x 109 CFU/g) on the 5th day fermentation but bacteria were dominant at the end (1.1 x 107 CFU/g). The highest decrease of reducing sugar and N-total contents were 0.240% at the 14th day and 0.159% at the 5th day, respectively. However, salt concentration was relatively stable and pH was varied within the range of 3.71-6.12 for the whole period fermentation. Keywords: fermentation, low salt, mandai, successio
PENGARUH SUHU DAN LAMA PROSES MENGGORENG (DEEP FRYING) TERHADAP PEMBENTUKAN ASAM LEMAK TRANS
No full textInfluencing of Deep Frying in Forming of Trans Fatty Acid. Frying process is one of the cooking’s techniques using vegetable oil. This process is commonly used in food industry, restaurants, food services, food retail and household scale. This is a laboratory experimental study which performed in laboratory of Public Health Nutrition FKM-UI and Integrated Laboratory IPB, Bogor from December 2005 until March 2006. It was conducted by two (2) type of treatment (used cooking oil ex cassava and meat) with 4 (four) times for each treatment. The objective of this study is to know the influence of frying by using deep frying (frying in high temperature and in a long time) and repeating to trans fatty acid formation in cooking oil. From the result revealed that fatty acid type mostly contained in a fresh cooking oil is oleic acid. Trans fatty acid was formed after second repeating of deep frying and increased in line with the frequent of repeating. Correlation test result had shown that negative association between elaidic acid (trans) and oleic acid (cis) (r = - 0,8; p value = 0.016). In accordance with the beginning of trans fatty acid formation, it would be better to use the cooking oil not more than twice. Keywords: deep frying, trans fatty acid, cooking oil  
DOMINASI CYANOBACTERIA PADA MUSIM PERALIHAN DI PERAIRAN LAUT BANDA DAN SEKITARNYA
No full textDomination of Cyanobacteria at Transition Monsoon around Banda Sea Area. Banda Sea had affected by monsoonfactor, this condition also influenced fitoplankton condition, but information about fitoplankton condition especiallyCyanobacteria group still not complete yet. Therefore had done the researched about fitoplankton in October 1998 andNovember 1999, that months is regarded as vice of transition monsoon. Fitoplankton samples were taken from the surface to 200 m depth to known the abundant, composition, and distribution of Cyanobacteria. The results showed that the abundant of Trichodesmium erahtraeum varied between 0.02-1.2 x 102 coloni m-3, the highest vale found in 100 mdepth and the lowest in 200 m depth. The abundance of Trichodesmium thiebautii varied between 0-8.8 x 102 cel m-3. Distribution of Trichodesmium erythraeum found until 50 m depth, their abundance high relative, this condition causedby nitrate concentration (r2 =28,30 %) and temperature (r2 =17,30 %). Based on their abundance, diversity, evennessand distribution Trichodesmium eryhtraeum dan Trichodesmium thiebautii dominated in transition monsoon.Keywords: Banda Sea, Transition Monsoon Cyanobacteri
DAMPAK PENCEMARAN LOGAM BERAT TERHADAP KUALITAS AIR LAUT DAN SUMBERDAYA PERIKANAN (STUDI KASUS KEMATIAN MASSAL IKAN-IKAN DI TELUK JAKARTA)
No full textEffect of Heavy Metals Pollution to Seawater Quality and Fishery Resources (Case Study on Fish Death in Jakarta Bay). Observation on heavy metals content in sea water were carried out in Jakarta Bay waters in May 2004. Heavy metals observed were Hg, Pb, Cd, Cu, Zn and Ni. This observation is conducted with fishes total death in this waters. Observation is done in Ancol beach 1 (3 stations), Ancol beach 2 (4 stations), Cilincing (3 stations), and Dadap River estuary (4 Station). The results showed that the average concentration of Hg, Cd and Cu in Ancol beach 1 were <0.001 ppm respectively, Pb is 0.001 ppm, Zn is 0.004 ppm, and Ni is 0.001 ppm. In Ancol beach 2 the average concentration of Hg, Cd, and Zn were <0.001 ppm, Pb is 0.002 ppm, Cu is 0.001 ppm and Ni 0.0017 ppm. In Cilincingthe average concentration of Hg, Cd, and Zn were <0.001 ppm respectively, Pb and Cu were 0.002 ppm, and Ni was0.0045 ppm. In Dadap River Estuary the average concentration of Hg and Cd were 0.001 ppm, Pb and Zn were 0.0027ppm, Cu was 0.001 ppm, and Ni between 0.0012 ppm. The concentration of that sixth heavy metals in Ancol beach 1, 2,Cilincing, and Dadap River estuary still lower compared to the Threshold Value (TV) stated by The Office of StateMinistry for Life Environment (2004) for sea biota namely 0.001 ppm for Hg and Cd, 0.008 ppm for Pb and Cd, 0.05 ppm for Zn and Ni. That way the concentration of Hg, Pb, Cd, Cu, Zn, and Ni in Ancol beach 1, 2, Clilincing and Dadap estuary not danger for sea biota, while in Ancol beach 3, the average concentration of Hg, Pb, and Cd has danger for sea biota. Thereby total death of fishes in this waters not caused by heavy metals, but by others factors, one of that factors is blooming toxic phytoplankton which produced toxin where sea water change to be red, and this phenomena known as red tide.Keywords: Jakarta Bay, Heavy Metals, Pollutio
CuInSe2 THIN FILM FOR SOLAR CELL BY FLASH EVAPORATION
No full textDeposition of thin films for material solar cell CuInSe2 are relatively simple. In this research mainly focused on the use of flash evaporation method, and the material created can then be characterized by optical and electrical properties. The optical characterization is done by X-ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS), and transmission and reflection by UV-VIS spectrophotometry. Electrical characterization is done by utilizing the Hall effect equipment. From these characterization, the atomic structure, absorption coefficient, energy gap, material type, composition of each elements and the mobility of CuInSe2 can be measured and determined. During process evaporation were carried out at substrate temperatures the range between 20ºC–415ºC. Keywords: chalcopyrite, flash evaporation, stochiometric, and thin fil
EFEKTIFITAS METODE ADITIF SPLINE KUADRAT TERKECIL PARSIAL DALAM PENDUGAAN MODEL REGRESI
No full textEfectivity ofAdditive Spline for Partial Least Square Method in Regression Model Estimation. Additive Spline of Partial Least Square method (ASPL) as one generalization of Partial Least Square (PLS) method. ASPLS method can be acommodation to non linear and multicollinearity case of predictor variables. As a principle, The ASPLS method approach is cahracterized by two idea. The first is to used parametric transformations of predictors by spline function; the second is to make ASPLS components mutually uncorrelated, to preserve properties of the linear PLS components. The performance of ASPLS compared with other PLS method is illustrated with the fisher economic application especially the tuna fish production.Keywords: additive model, transformation spline, partial least squar
KANDUNGAN TOTAL SUSPENDED SOLID DAN SEDIMEN DI DASAR DI PERAIRAN PANIMBANG
No full textoai:journal.ui.ac.id:article/35Total Suspended Solid Content And Sediment On The Bottom Surface Of Panimbang Water. The study of dynamics oceanography have been executed on June 2004 in the East season. Distribution of total suspended solid on the surface and bottom waters at the Estuary of Ciliman River is lower than Estuary of Cibungur River. Generally mud and silty mud of sediment on the bottom surface waters covered the western part of Panimbang beach. Gravel, silty sand and muddy sand with forams, fraction of mollust and corals found at the Southwest of the study area. In that area is also found many floating of Bagan Apung which is assumed as rich with fishes.Keywords: total suspended solid, estuary, sediment, forams, fraction of mollust and coral