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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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PRODUKSI BIODIESEL DARI CPO DENGAN PROSES ESTERIFIKASI DENGAN KATALIS H2SO4 DAN TRANSESTERIFIKASI DENGAN KATALIS CaO DARI CANGKANG KERANG DARAH Tengku Ryhaan Permata Sari Devi; Nurhayati '; Amilia Linggawati
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Abstract

Biodiesel is one of alternative fuel to replace diesel that was derived from petroleum. The objective of this research is to optimize biodiesel production from CPO raw material through esterification reaction catalyzed with H2SO4 and transesterification catalyzed with CaO originally from blood cockle. The esterification reaction was carried out with the weight variation of the catalyst and mol ratio of oil to methanol. Before performing biodiesel synthesis the water content and free fatty acid (FFA) were determined. Water content obtained was 0,4% and FFA was 5,0187%. The maximum biodiesel produced was 77,93% that was obtained from reaction by 2%wt H2SO4 catalyst with mol ratio of oil to methanol 1:24.
PEMBUATAN DAN KARAKTERISASI KARBON AKTIF DARI BAMBU BETUNG DENGAN AKTIVASI MENGGUNAKAN ACTIVATING AGENT H2O Rijali, Anggiyan; Malik, Usman; ', Zulkarnain
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Research on syinthesis of activated carbon has been conducted from bamboo betung with carbonization temperature of 400°C, 500°C and 600°C with duration time of 20, 40 and 60 minutes, respectively. Physical activation was carried out at 900°C for 20, 40, and 60 minutes with H2O steam as an activating agent. Bamboo betung characteristics as activated carbon was studied by analyzing shrinkage mass levels, proximate test, activated carbon absorption of the iodine and yield. Increasing of mass shrinkage was proportional to carbonization time. the higher carbonization temperature, the smaller water content and the greater content of ash. The higher temperature time resulted the higher value of iodine, and the longer activation time could decreased the yield. The best results of activated carbon was obtained at a temperature of 600°C in 60 minutes with shrinkage levels of mass of 69%, 3.8% of moisture content, 8.1% of ash contents and 31.5% of yield. Whereas the iodin number was found to be 379 mg/g.
PENENTUAN PENGURANGAN KEBISINGAN OLEH KARPET PADA RUANG TERTUTUP Yugo Setiawan; Juandi M; Krisman '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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It has been done a test of noise reduction using carpet by variating its thichness and its distance to noise source in a room (glass box). The thichnes of carpet was 0,246 cm, 0,492 cm and 0,738 cm. The noise reduction was measured at three different position of 30 cm, 50 cm and 70 cm from the noise source. The frequency of noise source used was 125, 250, 500, 1000, 2000, 4000 Hz. The measurement was performed at 95 cm to the nosie source by using sound level meter (SLM) SL 4112. The result showed that for a same thichness and variated measurement distance, the value of noise reduction was independent to the frequency. Noise reduction was getting smaller as increasing the thickness of the carpet. It’s value was maximum at the frequency of 2000 Hz and minimum at the frequency of 500 - 1000 Hz. The relation noise reduction to with frequency yielded a certain pattern, which was the larger carpet thichness the higher the nosie reduction would be. The lowest noise reduction was found at frequency of 500 - 1000 Hz, and the maximum noise reduction was accured at 2000 Hz.
MORFOMETRIK DAN MERISTIK IKAN BUNTAL MAS (Tetraodon fluviatilis H.B.) DI MUARA PERAIRAN BENGKALIS PROVINSI RIAU Tri Setia Ningsih; Roza Elvyra; Yusfiati '
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Morphometric and meristic analysis of pufferfish (Tetraodon fluviatilis H.B.) in estuary of Bengkalisconducted in April-August 2014, which aims to determine the characteristics morphometric andmeristik pufferfish (T. fluviatilis H.B.) in three different habitats. This study used the method of direct data collection sampling from study sites. Sampling was carried out at three different stations are three i.e Pakning River, Bengkel River Station and the Jangkang River with 30 male and 30 female. The results showed morphometric characters pufferfish gold female and male on the Pakning River greater than the Bengkel River and Jangkang River with status allometric growth is positive, negative allometric and isometric. The results showed of morphometric analysis pufferfish (T. fluviatilis H.B.) using T-test showed a significant difference in the pufferfish gold male and female at each study site. Analysis of meristik pufferfish gold male and female at each study site showed a significant difference.
ANALISIS LOGAM (Fe, Pb), Nitrat (NO3-), DAN SULFIDA (S2-) PADA LIMBAH TAMBANG BATUBARA PT. TRI BAKTI SARIMAS DI DESA PANGKALAN KUANSING Fadhli Kurniawan; Tengku Abu Hanifah; Subardi Bali
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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ne"> PT.Tri Bakti Sarimas (TBS) on Kuantan Singingi Regency has a great potency as liquid waste supplier in large quantity to environment as it contains hazardous heavy metals. This company has made four ponds as main water treatment facilities. Its efficiency of waste treatment installation (IPAL) could be determined by identificating the content of heavy metals (Fe and Pb), sulfide and nitrate contents at liquid waste reservoir inlet, second treatment pond, outlet and residence’s local pond. Determination of heavy metals (Fe and Pb) were done by using Atomic Absorption spectrophotometer (AAS) while UV-Vis spectrophotometer was used for sulfide and nitrate content identification. The respectively amount of Fe at inlet, second treatment pond, outlet, and residence’s local pond was 8,85 mg/L; 8,26 mg/L; 7,07 mg/L; 6,76 mg/L, respectively amount of Pb was 3,93 mg/L; 3,25 mg/L; 2,88 mg/L; 2,93 mg/L, respectively amount of sulfide (S-2 ) was 0,19 mg/L; 0,17 mg/L; 0,16 mg/L; 0,13 mg/L and respectively amount of nitrate (NO-3) was 1,23 mg/L; 0,73 mg/L; 0,51 mg/L; 0,03 mg/L. Waste water treatment in PT. TBS which has been used dolomite as adsorbent, shown the less efficiency for Fe, Pb, Sulfide and nitrate with average loss percentage less than 50 %.
SINTESIS DAN KARAKTERISASI MEMBRAN BIONANOKOMPOSIT SELULOSA BAKTERI-Ag SEBAGAI MEMBRAN ANTIBAKTERI Dwi Cahyaningsih; Andi Dahliaty; Amilia Linggawati
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Bacterial cellulose is a potential biopolymer that can be used in the medical field as an antibacterial membrane. Antibacterial membrane was synthesized from bacterial cellulose that was composited with silver nanoparticle that has antibacterial activity. Silver nanoparticles were impregnated into bacterial cellulose membrane to produce bacterial cellulose-Ag bionanocomposite membrane. Synthesis of silver nanoparticles was performed using reduction method with various concentrations of AgNO3 as precursor (0.5 mM, 1 mM, 1.5 mM) and sodium citrate as reducing and stabilizing agent. Bacterial cellulose-Ag bionanocomposite membrane was characterized by Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDX). The results of SEM-EDX characterization showed that bacterial cellulose-Ag bionanocomposite membrane with AgNO3 0.5 mM has smallest size of silver nanoparticles (30-60 nm) and distributed homogeneously in the bacterial cellulose membrane. Antibacterial test against Staphylococcus aureus and Escherichia coli was carried out by the agar diffusion and turbidimetry method. Bacterial cellulose-Ag bionanocomposite membrane did not show antibacterial activity in the agar diffusion method. In turbidimetry method, bacterial cellulose-Ag bionanocomposite membrane with AgNO3 0.5 mM showed antibacterial activity against Staphylococcus aureus and Escherichia coli. It was able to decrease Optical Density of Staphylococcus aureus (26,69%) and Escherichia coli (22,91%) compared to controls.
DESTILASI AIR LAUT MENGGUNAKAN PEMANAS MATAHARI DENGAN REFLEKTOR CERMIN CEKUNG Fanrico Sanjaya Tambunan; Muhammad Edisar; Juandi M
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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A research has been done in distilling seawater using solar heater with and without concave mirror reflector. The concave reflector mirror has been made with its diameter of 2.2 meters, height of 0.3 meters and focus of 1 meter. The reflector was placed on the ground and was directly illuminated by the sunlight. The collector which contained seawater was exactly placed on the focus of the reflektor. During the heating, thetemperature was measured every hour from 08.00 to 16.00 WIB. The observation was done for seven days. The results showed that maximum temperature of seawater using the reflector was about 100o C and 140oC at the focus and the best daily destilling volumewas 688 ml. The results distilling without reflector showed maximum temperature of seawater was about 64oC and the best daily destilling volume was 180 ml. The laboratory testing of the samples before and after distilling showed that there was significantly improvement of water quality, especially in salinity which decreased to be zero after distilling.
IMPUTASI MENGGUNAKAN PENAKSIR REGRESI UNTUK MENAKSIR RATA-RATA POPULASI PADA SAMPLING GANDA Bernad Fundika Marpaung; Rustam Efendi; Haposan Sirait
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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Estimators discussed in this paper are estimators that estimate a population mean with imputation method under double sampling design using regression estimators. Imputation methodsare used to estimate the missing data. This is a review of an article written by Thakur et. al [Journal of Reliability and Statistical Studies, 5(2): 21- 31]. There are three estimators that discussed and each of them is an unbiased estimator. The minimum variance of each estimator is compared in order to decide the most efficient estimator.
KOMUNITAS VEGETASI PIONIR DAN PERKIRAAN AKUMULASIBIOMASSA PADA LAHAN GAMBUT BEKAS TERBAKAR DI AREA TRANSISICAGAR BIOSFER GIAM SIAK KECIL – BUKIT BATU RIAU Dien Septiani; Haris Gunawan; Nery Sofiyanti
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
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After-burned peatland formed a new pioneer vegetation communities for biomass stored. In the next process, this vegetation reduce carbon emission into the air which caused by the releasing of stored carbon in natural peatland. The purpose of this research is to know the characteristics of natural succession in the early stage of pioneervegetation communities in after-burned peatland. Total biomass accumulation was counted using allometric equation BP = 0,1236 D2,3677, Wtotal= 0,1531080 (D)2,40, Btotal = 0.1923 D2.15, M = 7.50 × 10–2(D)2.60 dan M = 1.49 × 10–1(D)2.09 . The pioneer vegetation which were observed after the peatland fire were tenggek burung (Euodia sp.), kayu ara (Ficus sp.), mahang (Macaranga triloba), karet (Havea brasiliensis), sendayan (Scleria sumatrensis), alang–alang (Imperata cylindrica), senduduk (Melastoma malabathricum), paku-pakuan (Neprolepis hirsutula) dan rumput teki (Cyperus rotundus). The abundance of woody vegetation, Euodia sp., become very dominant after the first stage of  successionin after-burned peatland. Total surface biomass accumulation from the beginning of succession in all types of pioneervegetation was338,91 kg/ha/years.
METODE AGGREGATE COST PADA PREMI PENSIUN UNTUK KASUS MULTIPLE DECREMENT Riska br Silitonga; Hasriati '; Tumpal Parulian Nababan
Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam Vol 2, No 1 (2015): Wisuda Februari 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Matematika dan Ilmu Pengetahuan Alam

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This article discusses the aggregate cost method which is used to determine premium pension insurance under uniform assumption for the case of multiple decrements. The calculation of the premium is obtained by determining due life annuity and yearly present value benefit recieved by members of life insurance. Due life annuity and premium payment in a year is evaluated by determining in advance the life probability using uniform assumption for the case of multiple decrements.

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