Jurnal ILMU DASAR
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Graphite as A Hydrogen Storage in Fuel Cell System: Computational Material Study for Renewable Energy
Get PDFThe Hydrogen storage based-graphite materials have been investigated theoretically via Density Functional Theory (DFT) approach. The native graphite was compared to the modified graphite, namely the intercalation graphite (GICs, graphite intercalated compounds). Here the GICs was intercalated by alkali metals (Li, Na and K). The electronic structures, energetics and atomic orbital contributions of hydrogen-graphite system, GICs, and hydrogen-GICs were studied by calculation approach of gradient corrected PBE (Perdew-Burke-Ernzerhof) for recovery of exchange-correlation energy. The calculation was supported by using basis set of the plane waves whereas the computation of electron-core by using Ultrasoft Vanderbilt pseudopotential. The computational calculation provides four main studies i.e. molecular geometry relaxation, determination of electronic bands structure of energy, energy state density (DOS) and atomic orbital contribution by charge density differences.Keywords: Density Functional Theory, hydrogen gas, graphite intercalated materia
Effect of Addition of Monosodium Glutamate (MSG) on Coagulation Basin to Characteristics of Cellulose Acetate Membranes
No full textThe aim of recearch is study the effect of MSG in coagulation basin on cellulose acetat membranes properties. It was preparated by phase inversion technique. As the result showed that the higher the concentration of MSG in coagulation basin, which is character of membrane permeability coefficients and lower water flux. Dextran rejection of 11, 40, 100-200, and 500 kDa increased. The morphology analysis has shown that sub layer membranes structure with 2% MSG addition more uniform than 0,5% MSG addition.Keywords: cellulose acetat, phase inversion, MSG, coagulation basi
Antioxidant Activity Study And Α-glucosidase Inhibitor Phenolic Leaf Extract Bungur (Lagerstroemia speciosa) From Meru National Park Betiri
Get PDFStudy activities phenolic extract of bungur leaf as an antioxidant and inhibitor for the enzyme α-glucosidase was performed by spectrophotometric method. The extraction was carried out by three solvents with different polarity level in order to get three types of extracts namely hexane extract Bungur (HB), ethyl acetate extract Bungur (EAB), and the methanol extract Bungur (MB). The units, used in the analysis, is the total phenolic that standardized in gallic acid. The antioxidant activity of phenolic extracts Bungur leaf can be seen from its ability to reduce free radicals through the damping test DPPH radical, superoxide anion, and hydroxyl. Potential extract phenolic leaf Bungur as an inhibitor of α-glucosidase were analyzed by inhibition of α-glucosidase, but in this study also tested the inhibition of the enzyme α-amylase because both of these enzymes worked on the digestive system and hydrolyze carbohydrates. The results generally showed that the methanol extract of leaves Bungur potential as antioxidants that compared with standard vitamin C. In addition, it had as well as potential for inhibitors of α-glucosidase and α-amylase that compared akarbosa standard, which is expected to be a natural antidiabetic agent.Keywords: phenolic, bungur, antioxidant, inhibitor, α-amilase, α-glukosidaseÂ
Synthesis and Characterization of Hydrogels based on Graft Copolymerization of Acrylamide on Chitin resulted from Enzymatic Isolation of Shrimp Waste
No full textShrimp waste containing chitin 15-20%. Chitin can be isolated enzymatically by using proteaseenzymes derived from the waste itself. Waste of shrimp marinated in 1M H2SO4 for 10 days at pH1-2 and do control the pH and concentration of N-total every 24 hours. So that, this process canreduce the use of chemicals and environmental pollution. Enzymatic chitin obtained ash content1.789% and 5.322% of N-total. Results of IR showed characteristic functional groups of chitin areOH 3390.5 cm-1, NH (secondary amide) 3348.71 cm-1, C = O 1648.20 cm-1, C-N at 1313.96 cm-1,C-O 1115, 28 cm-1. Chitin is dissolved in 8% NaOH / Urea 4% for 36 hours (-20oC). Hydrogelsmade with a ratio (1: 6); (1: 8); (1:16); (1:24) w / w. The results showed the increasing amount ofacrylamide monomer, the greater the value% graft and absorption of water. Enzymatic chitinhydrogel showed the maximum value % graft is 2492.073%; and water absorption 1.794 g / g. IRhydrogel results indicate primary amide N-H stretching of acrylamide at 3349.77 and 3202.88 cm-1, C = O 1662.03 cm-1Keywords: hydrogel, chitin, acrylamide, graft copolymerizationÂ
Diversity and Density Gastropods in Mangrove Forest of Si Runtoh Beach, Baluran National Park
Get PDFThe mangrove forest is one of the coastal ecosystems of unique and productive. One of the animals that can be found in the mangrove ecosystem are gastropods. Gastropods constitute the largest class of the phylum of mollusks. Gastropods can usually be found in tidal areas, because these animals have a very high adaptability. The existence of mangrove gastropods in the area can be used as an indicator that the mangrove on the beach working properly or not. Diversity and density of research conducted in the mangrove forest Si Beach Runtoh Baluran National Park in February until April 2014 during a low tide maximal. The sampling method used in this research is the method of transects made per station. Transect length is 100 m, the total number of stations is 8, and the distance between the station 25 m. In one station consists of 8 transects, transects 15 m spacing, each transect consists of three plots measuring 5 m x 5 m. The results showed a diversity of mangrove Gastropods Si Beach Runtoh Baluran National Park is H '= 4,180 were classified as moderate while gastropods density obtained is 0.832 individu/m2.
Keywords: gastropods, diversity, densit
Application of Young Coconut Water and “Kascing†Fertilizer to Red Palm Seed Germination
No full textRedpalm isornamentplantwhichpotentiallytobecultured.Thescarcityofredpalmmadeithashighmarket value and need to be preserved. However, the germination growth of red palm is slower than other kinds of palm, so the best way to germinate the red palm seed is needed. The aim of this research is to determine the effect of apliccation some young coconut water concentration and kascing fertilizer to red palm seed germination. The research used factorial completely randomized design with 5 replication, the first factor is young coconut water concentration (0%, 25%, 50%, 75%, and 100%) and the second factor is germination media (steril sand and kascing fertilizer). Variables measured were live germination percentage, speed germination rate, radicula length, and plumula height. Results of this study showed that the best germination media is steril sand and 0% concentration of young coconut water
Synthesis zeolitic Imidazolate Framework-8 (Zif-8) In Solvothermal: The Effect Comparison of Metal-Ligand
Get PDFSynthesis of ZIF-8 (zeolitic Imidazolate Frameworks-8) have been successfully carried out by the reaction of zinc nitrate and 2-methylimidazolate in DMF (N'N-dimethylformamide) solvent at a temperature of 120 °C for 24 hours. Synthesis of ZIF-8 has been conducted five times with variations molar ratio of metal (Zn2+):ligand (MeIM) consecutive 1:1; 1:1.5; 1:2; 1:2.5 and 1:3 to study the influence of metal-ligand ratio of the crystallinity and morphology of ZIF-8 that was produced. The results of characterization by X-ray diffraction, FTIR and SEM show that ZIF-8 is synthesized with a ratio of metal: ligand = 1:2 showed the highest crystallinity and has the most irregular surface morphology with form box. Keywords: ZIF-8, solvotermal, metal/ligand ratioÂ
Utilization of Supported Liquid Membrane (SLM) in Separation of Pb(II) by Varying Concentration of Carrier and Feed Solution
Get PDFSupported liquid membrane (SLM) was prepared by reacting host material with carrier compounds. Carrier compound was Polyethylene Glycol-400 (PEG-400) that have been used with the variation of concentration 0, 2, 4, and 6%. The effect of its variations in SLM was characterized by FTIR and the performance was examined by transporting feed solution Pb(NO3)2 with variation 1, 5, 10, 15, and 25 ppm for 3 hours in pH 3. FTIR spectra depicted that the increasing concentration of PEG would arise the intensity of typical PEG’s functional groups such as -OH, C-O-C, and CH2-CH2 sp3. The optimum transport Pb(II) was achieved by SLM with 6% PEG. Variation of feed solution concentration showed the main effect in SLM activity. The higher of feed solution concentration would decrease of transport activity. The % extract and % recovery 1 ppm was higher than 25 ppm with 72,5% and 70,27% than 6,1% and 3,59%, respectively.
Keywords: supported liquid membrane, Pb(II), poly ethylene glycol, extraction and recovery, carrier compound
 
Effect of Environmental Factors on The Relative Fitness and Spatial Distribution of Mangrove Crabs (Scylla spp) in Blok Bedul Segoro Anak, Alas Purwo National Park, Indonesia
Get PDFThe mangrove forest are natural and renewable. resources Mangrove has the physical, chemicaland biological function which highly support the fulfillment of human needs and serve as a bufferbalance of the ecosystem in coastal areas. One of the functions associated with the mangrovebiological existence as a source of diversity of marine life. Marine life is affected by the presenceof mangrove forests among mangrove crab (Scylla serrata) to maintain the ecological balance andcause the energy cycle running fast. This study aims to determine the condition of environmentalfactors, the relative fitness and spatial distribution of mangrove crabin the mangrove forests BlockBedul Kali Segoro Alas Purwo National Park. Data from the study are described and classified bysimilarity of environmental factors, then performed multiple linear regression betweenenvironmental factors with relative fitness and spatial distribution of mangrove crabs. The resultsshowed that the average relative fitness mangrove crabs at all the research station is 69 with astandard deviation of 13.51. Spatial distribution of mangrove crab at any observation station isless than 1, so it can be concluded that the distribution is uniform. Environmental factors withrelative fitness mud crab significant correlation, but no significant correlation betweenenvironmental factors with the spatial distribution of mangrove crabs.
Keywords: Relative Fitnes Crab Mangrove, Mangrove Crab Spatial Distribution, Alas Purwo National Par
Development Design Labako Batik with Combine Fractal Geometry Dragon Curve and Tobacco Leaf Motif
No full textLabako Batik is a typical batik Jember, derived from the term "La Bako" is the language of Madura that describes the activities of farmers to plant and process the leaves of tobacco. The resulting motives are inspired by the potential of natural resources in Jember such as tobacco, cocoa, dragon fruit, coffee, bamboo, birds and butterflies. The selection of tobacco leaf pattern because Jember Regency as one of the best tobacco producing cities in Indonesia, so that the form of tobacco leaf becomes the most dominant characteristic in making Batako Labako. In recent years the application of fractal forms in batik began to be popularly known as fractal batik. Fractal batik is batik whose design is made with mathematical formulas done with computer technology. Development of Labako batik motif by generating the pattern of tobacco leaves using L-System and then combining with the fractal geometry of dragon curve that has been modeled, using techniques of geometry transformation in Matlab software. Keywords: labako batik, tobacco leaf, fractal, dragon curve, l-syste