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Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam
Published by Universitas Riau
ISSN : -     EISSN : -     DOI : -
Core Subject : Education,
Mathematics
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Articles 424 Documents
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DAMPAK KEBERADAAN SARANG RAYAP TERHADAP SIKLUS NITROGEN PADA LAHAN GAMBUT TERDEGRADASI DI DESA TANJUNG LEBAN KABUPATEN BENGKALIS Fransisca '; Tengku Ariful Amri; Sofia Anita
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Peat soil in the Bengkalis Regency, Riau Province,  degrades partially due to fires and land clearing so that decreases soils fertility. Therefore, a solution is needed to increase the fertility of peatlands. This study aimed to understand the effect of termite nest presence on nitrogen cycle at the degraded peatlandecosystem in the Tanjung Leban Village, Bengkalis Regency. The measured parameterswere the amount of ammonium (NH4+) and nitrate (NO3-) ions in soil samples around termite nests, and they were analyzed using an Auto-analyzer. The analysis results of 10 termite nests indicated that the highest values of NH4 + and NO3-ions were in soil samples S8and S 10, respectively. In addition, the other soil samples and control didnot show a significant difference. Based on this results, we concluded that the termite nests in the study sites generally did not significantly affect the nitrogen cycle in thatarea. This results were based on the analysis of variance (ANOVA) and Duncan's test at α=0.05.
ANALISIS SIFAT-SIFAT PERMUKAAN BIRNESSITEYANG DIPREPARASI DARI DUA AGEN PEREDUKSI BERBEDA Hartini Azhar; Amir Awaluddin; Akmal Muchtar
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

The layered manganese oxides having birnessite structure have been successfully synthesized using the two different types of reducing agents by solid-state ceramic method.  The reducing agent used  in  this  study was  oxalic acid and glucose.  Birnessite synthesized has been characterized using XRD, SEM and methylene blue adsorption. The XRD results indicated that the two types of reducing  agents produced mainly birnessite phases with different crystallinity .Birnessites  synthesized from two reducing agents have different surface properties as indicated from data of SEM and methylene blue adsorption.
STUDI XRD MANGAN OKSIDA BIRNESSITE YANG DIPREPARASI MELALUI METODE SOL-GEL DAN KERAMIK Dian Anggraini; Amir Awaluddin; Pepi Helza Yanti
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Birnessite  is a naturally occurring layered manganese oxide found as a manganese nodules  in sea floor or    soil deposit. In this study, birnessite was synthesized  using two types of methods, solid state ceramic  approach and sol-gel reaction both KMnO4 and maltose were used as reactants in these two methods.  The products were then characterized using XRD for determination of phases, crystallinity and purity. The results showed  the both techniques lead to  the  formation of birnessite with different crystallinity and purity. The ceramic method produced  more crystalline and pure birnessite than that of sol-gel.  The typical reaction parameters for the synthesis birnessite by the ceramic method were 3:1 mole ratio (KMnO4over maltose) calcination at  700o C for 7 hours with  the  93,7%  purity  of  birnessite. However,  by  the sol-gel  method birnessite  produced only  31,8%  with the following condition  4:1 mole  ratio (KMnO4 over maltose) and calcination temperature of 450o C for 2 hours.
SINTESIS DAN UJI AKTIVITAS ANTIBAKTERI SENYAWA ANALOG PIRAZOLIN TURUNAN 3’BROMOKALKON INTI NAFTALEN Sriatun Sadiah; Yuharmen '; Jasril '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Analog compound  of  3'bromochalcone  pyrazoline  derivative  5-  (3-bromofenil)  -3-(naphthalene-2-yl)  -1-fenill-4.5-dihydro-1H pirazol (PP2) was  synthesized through nucleophilic addition reactions using glacial acetic acid catalyst under microwave radiation. PP2  compound  was obtained as yellow crystal  with yield  of  77.73%.  The purity of pyrazoline analog coumpound has been tested using TLC  observation, determination of melting point,  HPLC  analysis  and characterized by UV spectroscopy, IR spectroscopy, Mass spectroscopy and NMR spectroscopy. Antibacterial test conducted by the agar diffusion method with concentration of 10 μg/disk dan 30 μg/disk against Gram-positive bacteria, B. subtilis and S. aureus, and Gram-negative bacteria, E. coli and S. typhi. PP2  compound  showed that there was a low antibacterial activity. However, the inhibition of PP2 against Gram-positive bacteria is greater than  that of Gram-negative bacteria.
PENENTUAN TINGKAT KEMATANGAN TERMAL MINYAK MENTAH PENDALIAN IV KOTO, ROKAN HULU BERDASARKAN PARAMETER INDEKS METILPHENANTREN Ilham, Rendi; Tamboesai, Emrizal M.; Sophia, Halida
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Determination of thermal maturity level aims to determine the feasibility of  petroleum wells to be exploited because there are many  new wells of petroleum unexploited in the Riau area,  especially Pendalian oil field.   Determination of    thermal maturity  level Pendalian oil fieldwas  done by taking three samples from different wells. The samples were characterized using gas chromatography (GC) for a saturated fractions  and using gas chromatography-mass spectroscopy (GC-MS) for aromatic  fractions.In this study the ratio of isoprenoid and n-alkanewere  used as initial parameters in determining the thermal maturity and  reinforced with methy lphenatren  index.Metilphenantren index were  used  of MPI-3 and metilphenantren ratio (MPR).The results of the ratio of n-alkane  and isoprenoid indicated  that oil of Pendalian oil field was  mature.This was also confirmed by methylphenantren index that hadvalues of MPI-3 0.741; 0.748; 0.731,  and values of MPR 0.829;  0.814; 0.831 indicated  that Pendalian oil field  was  mature  and classified into a low maturity level.
SINTESIS PIRAZOLIN DARI KALKON 3-KLORO INTI NAFTALEN DAN UJI AKTIVITASNYA SEBAGAI ANTIBAKTERI Ary Puspita; Hilwan Yuda Teruna; Jasril '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Pyrazolines have been reported to possess many of interesting biological activities such as antimicrobial,  antidepressant,  antitumor, antioxidant, antiinflammatory, anticancer and  anticonvulsant  activity .  In this research, a  compound  of 1-phenyl-3-(2-naphthyl)-5-(3-chlorophenyl)-2-pyrazoline  was synthesized by cyclization of  (E)-3-(3-chlorophenyl)-1-naphthalene-2-yl-prop-2-en-1-on and phenylhydrazine  using glacial acetic acid  as  a  catalyst under  microwave  irradiation. The compound showed a good yield and  it  was characterized by UV, IR, 1 H-NMR  and 13 C-NMR  spectroscopy. The antibacterial activity of this compound was determined using agar diffusion method against Gram positive bacteria  (Bacillus subtilis  and  Staphylococcus aureus) and Gram negative bacteria  (Escherichia coli  and  Salmonella typhi). The compound showed very poor activity against Salmonella typhi.
ISOLASI DAN PEMEKATAN ENZIM SELULASE Trichoderma sp. LBKURCC28 MENGGUNAKAN METODE PENGGARAMAN (NH 4 ) 2SO 4 80% SERTA PENENTUAN AKTIVITAS DAN AKTIVITAS SPESIFIK ENZIM Febry Kurniawan; Titania T. Nugroho; Andi Dahliaty
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Cellulase enzyme activity can be increased by concentrating the enzyme using saturated ammonium sulfate ((NH4) 2SO4) 80%. Precipitated enzyme was redissolved by the addition of acetate buffer solution pH 5.5 to 1/70 times its original volume. Cellulase enzyme activity was determined using substrates CMC and avicel. The test results showed that the activity of concentrated CMCase increased 75 times and avicelase enzyme activity increased 9 times. Activity and specific activity concentrated CMCasewas 0,4060±0,0845 U/ml and 0,7306±0,1526 U/mg respectively, while activity and specific activity of concentrated avicelase were 0,0129±0,0182 U/ml and 0,0232±0,0328 U/mg respectively.
ISOLASI METABOLIT SEKUNDER DAN UJI TOKSISITAS EKSTRAK METANOL DAUN TANAMAN Cerbera odollam Gaertn. (APOCYNACEAE) Rissan Ramaesy Tobing; Hilwan Yuda Teruna; Yuharmen '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Cerbera odollam Gaertn is a plant found in Indonesia and used as a medicine. Isolationof its secondary metabolites and toxicity assay on leaves of this plant have been doneby macerating method with methanol solvent. The separation was carried out by vacuum liquid chromatography (VLC) and column chromatography, respectively. Characterization of the fractions was established using UV-Vis, FT-IR, and NMR. Toxicity assay was conducted by Brine Shrimp Lethality Test (BSLT) method. The LC 50 of 2 th , 4 th to 11 th fractions of the methanol extract were 874.78; 1076.71; 7.88; 0.85; 3.02; 0.23; 8.62; 3.94; 223.46; and 168.23 ppm respectively. The 3 th fraction was not toxic, where as other fractions were toxic and potential as anticancer.
SINTESIS BIODISEL MENGGUNAKAN KATALIS CaO CANGKANG KERANG DARAH: OPTIMALISASI TEMPERATUR REAKSI DAN KALSINASI KATALIS Zaidi Asyadiqi; Nurhayati '; Muhdarina '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Blood cockle shells (Anadara granosa) can be used as heterogeneous catalysts for biodiesel production because it contains CaCO 3 that can be decomposed into CaO. In this study, blood cockle shells was calcined at temperatures of 800, 900 and 1000 oC for 10 hours. The synthesis of biodiesel was done by transesterification process of cooking oil and methanol. The condition variables for biodiesel synthesis studied were reaction temperatures (55, 60, 65 and 70 °C) and catalyst calcination temperatures (800, 900 and 1000 °C). The optimum of biodiesel results was 71.58 % with catalyst weight conditions of 4 % (w/w), the mole ratio of oil- methanol 1: 6, reaction temperature at 60±2 oC for 3 hours using catalyst calcination at 900 o C for 10 hours. Biodiesel obtained has a water content of 0.031 %, density of 870 kg/m 3 , viscosity of 3.63 mm 2 /s, flash point of 150 oC, carbon residue of 0.029 %, acid number of 0.23 mg KOH/g, iodine number of 50.26 g-I 2 /100 g and cetane number of 67.9. All of the characteristics of biodiesel correspond to the SNI for biodiesel (SNI 04-7182-2006).
POTENSI ABU DARI TULANG IKAN TONGKOL SEBAGAI ADSORBEN ION MANGAN DALAM LARUTAN Puji Astuti; Sofia Anita; Tengku Abu Hanifah
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 1, No 2 (2014): Wisuda Oktober 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Tuna fish bone waste has not been used optimally yet. The tuna bone contains phosphate calcium and carbonate calcium so that oxide calcium can be formed when they are calcinated. Oxide calcium pattern which is relatively opened is hexagonal in shape, inside the shape H+ and other ions are trapped hence it is potential to be an adsorbent. This study was conducted to determine the absorption ability of oxide calcium based on various concentrations and contact times. Manganese analysis was performed using Atomic Absorption Spectroscopy (AAS). The highest absorption ability of oxide calcium to manganese based on variation of concentrations (10 mg/L, 30 mg/L dan 50 mg/L) was 60.334% for 50 mg/L of manganese concentration and immerse time of 20 hours with 5, 10, 15, 20, and 24 hours contact time. Optimum asorption was found at 20 hours of immerse time and 50 mg/L of manganese concentration analyzed with a value of 98.19%. Level of calcium and oxide calcium in ash of tuna bones analyzed by complexometry were 22.44% and 31.36%, respectively.

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