Posman Manurung
Universitas Lampung

Published : 11 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 11 Documents
Search

Pengaruh Laju Penginjeksian Doping Sulfur terhadap Aktivitas Fotokatalis Nanotitania Menggunakan Metode Sol Gel Delfi Oktavia Amrani; Posman Manurung; Pulung Karo Karo
Jurnal Teori dan Aplikasi Fisika Vol 7, No 2 (2019): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v7i2.2246

Abstract

Abstract. Synthesis of sulfur doped titania (S-TiO2) was carried out through sol-gel method. Titanium isopropoxide (TTIP), tween-80, isopropanol and sulfuric acid (H2SO4) as a source of sulfur doping were used as raw material. The aimed of this research is to study the effect of the rate of sulfur doping injection by using an injection pump toward S-TiO2 photocatalyst activity. Four sulfur doping samples were prepared with rate injection of 4 ml/30; 4 ml/60; 4 ml/90 and 4 ml/120 minutes respectively. Titania powder was calcined at temperatur of 450 oC for 5 hours. The sintered samples were tested for photodegradation of remazol yellow under UV irradiation. Physical characteristics were analyzed using transmission electron microscopy (TEM) and UV-Vis Spectrophotometer. The result of the UV-Vis spectrophotometer showed that sample with an injection rate of 4 ml/30 minutes showed higer photocatalyst activity with the particle size is (7,1 nm ± 1,9 nm)
Pengaruh Ethanolamina (MEA) dalam Pembentukan TiO2 dari Bahan Awal Ti Butoksida Rika Rahayu; Posman Manurung; Yanti Yulianti
Jurnal Teori dan Aplikasi Fisika Vol 7, No 2 (2019): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v7i2.1946

Abstract

Titanium dioxide has been prepared through the sol gel method using the addition of ethanolamine. The research was conducted to study the effect of MEA on the formation of TiO2. The amount of MEA was varied to 0; 0.5; 1; 1.5; and 2 ml respectively. The samples were calcined at a temperature of 500 ºC. TiO2was characterized using X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and photocatalyst tests using UV lamps. The XRD characterization results showed that in the A  sample an anatase phase was formed whereas in the Csample an anatase phase and a brookite phase were formed. The resultof TEM characterization using ImageJ software show that the particle size of TiO2 is26,1  nm, respectively. The results of the characterization of the fastest photocatalyst catalyst test occurred in sample C which the variation of MEA is 1 ml.  
Sifat Fisis Komposit Polietilen/Nanotitania Sebagai Fungsi Ketebalan Nola Fricilia; Posman Manurung; Agus Riyanto
Jurnal Teori dan Aplikasi Fisika Vol 7, No 1 (2019): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v7i1.1930

Abstract

Physical properties of polyethylene (PE)/nanotitania composite as a function of thickness have been studied. The material used is PE and nanotitania. The blending of PE with nanotitania was carried out by melting polyethylene at 95 °C for 5 minutes then added nanotitania 5 wt% and 10 wt% and heated at 124 ° C for 30 minutes. Then printed using barcoater with size 6, 12 and 25 µm with four repetitions. Variations were performed to determine the effect of composite thickness of polyethylene/nanotitania on electrical properties and functional groups. FTIR results show that as the thickness of the absorption sample increases, new functional groups appear, namely hydroxyl and carbonyl. The LCR results show the smallest conductivity value, sample 5 wt% PE / nanotitania with 6 µm size and the largest 10% PE/nanotitania sample with a size of 25 µm each at 2,302 x 10-5 S/m and 3,121 x 10-5 S/m at a frequency of 105 Hz. While the largest dielectric constant value is a sample of PE/nanotitania 5 wt% with a size of 6 µm and the smallest sample PE/nanotitania 10 wt% with a size of 6 µm at a frequency of 105 Hz. Based on these characteristics, the 5 wt% PE/nanotitania sample with a size of 6 µm is the material with the best dielectric properties so that the sample has the potential to be used as a cable insulator.
Pengaruh Thiourea Sebagai Sumber Doping Sulfur terhadap Sintesis Nanotitania Nabilah Rafidiyah; Posman Manurung; Pulung Karo Karo
Jurnal Teori dan Aplikasi Fisika Vol 5, No 2 (2017): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v5i2.1815

Abstract

Sulfur–doped TiO2 were prepared by sol gel method using thiourea as sulfur source. The amount of thiourea solutions are 0; 0.5; 1.0; 1.5 and 2 ml, respectively. Sulfur-doped TiO2 was calcinated at 450 °C. Sulfur-doped TiO2 and pure TiO2 were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM). Photocatalyst tests were carried out undersunlight and UV lamp. Based on XRD characterization, the samples are anatase phase. And particle size was calculated using Scherrer equation and results of  8.94 and 12.98 nm, respectiely for TBT-1.5 and TBT-0.5. TEM characterization showed that particle size of sulfur-doped TiO2 and pure TiO2 are 8.6 and 12.5 nm. Compared to undoped TiO2, sulfur-doped TiO2 has a better photocatalyst activity for degradation of remazol golden yellow under visible light.
Pengaruh Variasi NaOH terhadap Karakteristik Nanosilika Berbasis Batu Apung Nurqori Setiawati; Posman Manurung; Simon Sembiring
Jurnal Teori dan Aplikasi Fisika Vol 6, No 2 (2018): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v6i2.1842

Abstract

Nanoparticle of silica from pumice rockhas been synthesizedby using extracted method of NaOH with varying of 2,5 Mand 3,5 M.The pumice was extracted using NaOH, silica titration usingH2SO4 and purification of silica using HCl. The solution was calcination at 700°C for 2 hours. The XRD result showed that diffraction pattern of amorphous silica. The EDS result confirmed the purity of silica for NaOH 3,5 M were 75,84%. Particle size from TEM result is(11,32 ± 0,922) nm for NaOH 3,5 M. The surface area for NaOH of 2,5 M and 3,5 M are 178,7 m2/g and186,2m2/g respectively.
Pengaruh Variasi HCl Pada Pemurnian Silika Berbasis Batu Apung Jayanti Pusvitasari; Posman Manurung; Pulung Karo Karo
Jurnal Teori dan Aplikasi Fisika Vol 6, No 1 (2018): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v6i1.1833

Abstract

Silica from pumice natural rock was extracted by varying HCl of 1M and 2M. Fristly, pumice was heated to 400°C for 4 hours to activate the component of material.Three steps were used in obtaining pure silica. Silica extraction by using NaOH, silica titration by using H2SO4, and purification silica with HCl. The purified powder was calcined at 800°C. The characterization of XRD (X-Ray Diffraction) and SEM-EDS (Scanning Elektron Microscopy - Energy Dispersive Spectrometry) were performed for samples after and before purification to know the phase structure and microstructure and pumice powder content. The XRD results was show diffraction pattern of the amorphous shaped SiO2 with some crystalline peaks is an other oxide compound than SiO2 for the starting material, and an anorite crystal phase in the HCl 1M and 2M variations. This is confirmed by EDS results what showing the silica content has the highest percentage of 65.88% for the raw material, 67.83% for HCL 1M and 69.63% for HCl 2M variation after purification. While the SEM results identified the microstructure for the raw material has a clear but not entirely homogeneous that is the identification of the sample in an amorphous state, whereas the sample after purification of the microstructural result shows non-homogeneous grain size, unclear grain boundary boundaries and an algomeration (agglomeration ) which is also the identification of the sample in an amorphous state.Silica from pumice natural rock was extracted by varying HCl of 1M and 2M. Fristly, pumice was heated to 400°C for 4 hours to activate the component of material.Three steps were used in obtaining pure silica. Silica extraction by using NaOH, silica titration by using H2SO4, and purification silica with HCl. The purified powder was calcined at 800°C. The characterization of XRD (X-Ray Diffraction) and SEM-EDS (Scanning Elektron Microscopy - Energy Dispersive Spectrometry) were performed for samples after and before purification to know the phase structure and microstructure and pumice powder content. The XRD results was show diffraction pattern of the amorphous shaped SiO2 with some crystalline peaks is an other oxide compound than SiO2 for the starting material, and an anorite crystal phase in the HCl 1M and 2M variations. This is confirmed by EDS results what showing the silica content has the highest percentage of 65.88% for the raw material, 67.83% for HCL 1M and 69.63% for HCl 2M variation after purification. While the SEM results identified the microstructure for the raw material has a clear but not entirely homogeneous that is the identification of the sample in an amorphous state, whereas the sample after purification of the microstructural result shows non-homogeneous grain size, unclear grain boundary boundaries and an algomeration (agglomeration ) which is also the identification of the sample in an amorphous state.
Pengaruh Ethanolamina Terhadap Pembentukan Fasa, Ukuran Partikel, dan Luas Permukaan Spesifik Nanotitania Menggunakan Metode Sol Gel Renita Maharani Fauzi; Posman Manurung; Yanti Yulianti
Jurnal Teori dan Aplikasi Fisika Vol 9, No 2 (2021): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v9i2.2716

Abstract

Nanotitania has been prepared by sol gel method using ethanolamine as surfactant. This research was conducted to determine the effect of ethanolamine on the phase formation, particle size and surface area of TiO2. In this study Ti-butoxide was used as a precursor and ethanol as a solvent, and then HCl. The amount of ethanolamine was varied to 0; 0.5; 1; 1.5; and 2 ml. The samples were calcined at a temperature of 500ºC for 4 hours. TiO2 was characterized using X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Surface Area Analyzer (SAA) with BET method. The results of XRD characterization showed that in samples A-0.0 and A-0.5 an anatase phase was formed, whereas in the sample A-1,0 and A-1,5 an anatase, brookite, and rutile phases were formed with a weight percentage of 57,65 ± 1,6% wt; 27,06 ± 1,8% wt, and 15,29 ± 0,4% wt. Meanwhile, for sample A-1,5  it is 69,96 ± 1.6% wt, 24,52 ± 1,5% wt, and 5,52 ± 0,3% wt. Sample A-2.0 only produced anatase and brookite phases with weight percentages of 78,53 ± 1.5% wt and 21,47 ± 1.5% wt. The results of TEM characterization using ImageJ software show that the TiO2 particle size in sample A-1,0 was 15,8 ± 1,0 nm. The results of the analysis surface area of sample A-1, produced the largest specific surface area, that is 172 m2/g, the smallest specific surface area was produced in sample A-1,5  that is 72,07 m2/g.
Efek Variasi Konsentrasi NaOH pada Pembentukan Struktur Selulosa Cladophora sp. Sri Wahyu Suciyati; Posman Manurung; Junaidi Junaidi; Rudy Situmeang
Jurnal Teori dan Aplikasi Fisika Vol 10, No 1 (2022): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v10i1.2888

Abstract

The effect of NaOH concentration values was observed on the cellulose structure of Cladophora. Cladophora cellulose is synthesized from Cladophora sp., a green alga that lives in aquatic environments (seawater and freshwater) and soil surfaces (rocks and wetlands). Cellulose synthesis is carried out through the processes of bleaching, alkali hydrolysis, and acid hydrolysis. Bleaching uses NaClO2, alkaline hydrolysis uses NaOH with varying concentrations (0.4; 0.5; 0.6; 0.7; 0.8 M), while acid hydrolysis uses 5% HCl. The physical properties of cellulose were analyzed using Fourier Transformation Infra-Red (FTIR) to determine functional groups, X-Ray Diffraction (XRD) to determine crystal structure, and scanning electron microscopy (SEM) to determine the morphology of cellulose structure.  FTIR pattern analysis showed peaks with OH group stretching at 3331, 3347, 3360 cm-1, CH group stretching at around 2929 cm-1, C = O stretching at 1640-1650 cm-1, and CH2 flexural stretching at 1420-1430 cm-1 in all samples. XRD pattern analysis confirmed the recovery of Cladophora cellulose from a highly crystalline of sample c (NaOH 0.5 M) with a crystallinity index of 94.0 % and a particle size of 31.54 nm. SEM image analysis showed the surface morphology of Cladophora rod-shaped raw material with an average diameter of 21.30 µm. At the same time, Cladophora cellulose refers to the formation of a web-like nanofibril network with an average diameter of 30.63 nm. These results indicate that the synthesis has successfully removed lignin, hemicellulose, and amorphous group in Cladophora and formed crystalline cellulose confirmed by nano-sized cellulose.
KARAKTERISTIK FUNGSIONALITAS DAN MIKROSTRUKTUR KOMPOSIT ASPAL-SILIKA-KARBOSIL Lady Permatasari; Simon Sembiring; Posman Manurung
Jurnal Teori dan Aplikasi Fisika Vol 10, No 1 (2022): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v10i1.2908

Abstract

Synthesis and characterization of asphalt have been modified with silica and carbosil composite. This research was conducted to determine the functionality and microstructure of the asphalt-silica-carbosil composite with a weight composition ratio of 0:50:50; 15:42.5:42.5; 20:40:40; 25:37.5:37.5; 30:35:35; 35:32.5:32.5. Silica is obtained from rice husk using the sol gel method and carbosil was obtained by the pyrolysis method. The results of FTIR analysis obtained that the functional groups formed from each composition variation were O-H, C-H, C≡C, C=O, Si-O-Si, and Si-O. The results of microstructural analysis showed the presence of lumps scattered on the surface. The composition of the elements formed is dominated by elements of C, Si, O, N, and a little Na, K and S. Variations in the composition of the sample indicate an increase in the density value, a decrease in the value of water absorption and hardness.Telah dilakukan sintesis dan karakterisasi aspal yang dimodifikasi dengan komposit silika dan karbosil. Penelitian ini dilakukan untuk mengetahui fungsionalitas dan mikrostruktur komposit aspal-silika-karbosil dengan perbandingan komposisi berat 0:50:50; 15:42.5:42.5; 20:40:40; 25:37.5:37.5; 30:35:35; 35:32.5:32.5. Silika diperoleh dengan menggunakan metode alkalis dan karbosil diperoleh dengan metode pirolisis. Hasil analisis FTIR diperoleh gugus fungsi yang terbentuk dari setiap variasi komposisi yaitu O-H, C-H, C≡C, C=O, Si-O-Si, dan Si-O. Hasil analisis mikrostruktur menunjukkan adanya gumpalan yang mengindikasikan sebagai silika-karbosil yang tersebar di permukaan. Komposisi unsur yang terbentuk adalah didominasi unsur C, Si, O, N, dan sedikit Na, K dan S. Variasi komposisi sampel menunjukkan adanya peningkatan nilai densitas, penurunan nilai daya serap air dan kekerasan.
Pengaruh Temperatur Austenisasi terhadap Struktur Mikro dan Nilai Kekerasan Material 14%Cr-3%Ni-2%Mo-2%C untuk Aplikasi Bola Gerus Imaniar Romaeni; Posman Manurung; Fajar Nurjaman
Jurnal Teori dan Aplikasi Fisika Vol 5, No 2 (2017): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v5i2.1381

Abstract

This study was conducted to determine the effect of heat treatment in the form of sub-critical, austenization, quenching and tempering the hardness values of the white cast iron material as consideration for testing wear resistance of local and foreign products as grinding balls. Samples was treated sub-critical at a temperature of 700°C with a hold time of 2 hours and continued with austenization temperature variation of 850, 950 and 1050°C with a hold time of each sample is 5 hours. The optimum hardness value was obtained at a temperature of 950°C austenization in the amount of 68.3 HRC and decreased at a temperature of 1050°C. It is because the solubility of carbon elements making up the matrix. Next will be tempering at a temperature of 250°C and holding time 2 hours hardness values decreased but the value of wear resistance is obtained even better ie grinding balls of 0.03 g/kg of product due to the combination of its constituent elements, namely chromium-molybdenum and nickel are high the presence of wear phenomena induced martensite.