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Recent Submissions

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SINTESIS DAN KARAKTERISASI KATALIS CaO-SiO2 DARI CANGKANG KERANG DARAH DAN SABUT PINANG UNTUK PRODUKSI BIODIESEL
(Elfitra, 2023-12) Marlinda, Ririn
Calcium oxide (CaO) is a catalyst that is widely used for biodiesel synthesis reactions because it has relatively high base strength, but the CaO catalyst has the weakness of a low surface area. Therefore, to increase biodiesel yield the CaO catalyst needs to be modified using silica to increase the surface area of the catalyst and its catalytic activity. The aim of this research is to synthesize and characterize the CaO catalyst modified by SiO2 areca palm ash using the impregnation method with the SiO2 ratio of 3% w/w to the weight of CaO. The resulting catalyst was applied for biodiesel production with yield optimization using a Response Surface Methodology (RSM) design. Analysis using BET shows that the surface area of CaO-SiO2 has increased. XRF analysis for the 3% CaO-SiO2 catalyst obtained a SiO2 composition of 0.66 and a CaO composition of 97.496%. Based on the optimum results, the highest biodiesel yield was 94.29%.
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SINTESIS NANOPARTIKEL PERAK MENGGUNAKAN EKSTRAK DAUN JABON PUTIH (Anthocephalus cadamba Miq.)
(Elfitra, 2023-12) Nainggolan, Rezky Yoshua
Biosynthesis is one of the synthesis methods that used plants as reductor. The secondary metabolite compund in plants can be used as bioreductor fo synthesize silver nanoparticles. The purpose of this research was to synthesize silver nanoparticles using jabon putih leaf extract (Anthocephalus cadamba Miq.) using biosynthesis method. The extract was obtained from maseration method by mixing 5 g jabon putih leaves with 250 mL Aqua demineralized. After that, silver nanoparticles was synthesized with biosynthesis method that accompanied with variation of pH and AgNO3 solution’s concetration. The pH was variated in 3, 5, 7, 9, and 11 and AgNO3 solution’s concetration was variated in 0.1 mM, 1 mM, and 10 mM. the formed silver nanoparticles were analyzed using UV-Vis Spectrophotometry and Fourier Transform Infra Red (FTIR). The result of this research are showed in UV-Vis and FTIR’s Spectra. UV-Vis spectra analysis showed the existence of an optimum stable absorbance peak at wavelength of 431 nm with the absorbance of 1.331. This result was further supported by FTIR spectra, which shows the presence of the O-H group, a functional group that reduce Ag+ ions into Ag0. The best conditions to synthesize silver nanoparticles in this research were found to be at pH 3 with a concentration of AgNO3 solution of 1 mM.
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AKTIVITAS ANTIDEPRESAN EKSTRAK n-HEKSANA BIJI PINANG TUA DENGAN METODA FORCED SWIM TEST PADA MENCIT JANTAN (Mus musculus)
(Elfitra, 2023-12) Rahayu
Depression is a mental health disorder characterized by unstable mood and frequent emotional changes. Antidepressant drugs can be used as initial pharmacological therapy for depressive disorders. The Forced Swim Test (FST) method is a method used to see antidepressant activity. This study aims to determine the antidepressant activity of n-hexane extract of mature areca nut seeds using the FST method acutely. FST was used because it is one of the most widely used in vivo methods for detecting antidepressant drugs in test animals. The injection into mice was carried out intraperitoneally 1 hour before FST at a dose of 10 mg/kg and the control group was only injected with 0.9% saline. N-hexane extract of old areca nut seeds at a dose of 10 mg/kg was not effective as an antidepressant because there was no significant reduction in immobility time compared to controls.
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PENGARUH PENAMBAHAN KARBON NANOTUBE PADA DENSITAS KARBON AKTIF BERBASIS KULIT BIJI MAHONI
(Elfitra, 2023-12) Sitinjak, Polikarpus Ebenezer
The influence of adding Carbon Nanotube (CNT) on the density of activated carbon derived from mahogany seed husk. Various additions of CNT, namely 2%, 4%, and 8%, were applied during the synthesis of activated carbon to assess their impact on the material density. The characterization process involved measuring the thickness, diameter, and weight of the activated carbon before and after pyrolysis. The results of the analysis indicate that the addition of CNT significantly affects the density of activated carbon, with the highest reduction value reaching 41.20%. The incorporation of CNT at certain levels can lead to measurable changes in the material density characteristics.
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SINTESIS KOMPOSIT MnOx/ABU CANGKANG KELAPA SAWIT UNTUK DEGRADASI METILEN BIRU: VARIASI SUHU KALSINASI
(Elfitra, 2024-12) Sibarani, Panji Haratua; Awaluddin, Amir
Manganese oxide is an important compound in nature for the transformation of various compounds into simpler compounds. Synthesis of manganese oxide can be carried out using the sol-gel method. The aim of this research is to examine the effect of calcination temperature on the characteristics and catalytic activity of MnOx/ACKS composites. The synthesis of the MnOx/ACKS composite was carried out by mixing KMnO4, glucose and activated ACKS. The MnOx/ACKS composite was characterized using XRay Diffraction (XRD). The XRD characterization results show that the MnOx/ACKS composite consists of a quartz phase and a mixed phase of manganese oxide such as managanosite, cryptomelane, hausmanite and binnerssite. Degradation of methylene blue at a concentration of 12.5 ppm, a volume of 5 mL of H2O2 and a composite mass of 25 mg was able to degrade methylene blue by 86.67% within 120 minutes.