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All Journal Spektra: Jurnal Fisika dan Aplikasinya Jurnal Teori dan Aplikasi Fisika
Leni Rumiyanti
Universitas Lampung
Aerospace Engineering Electrical & Electronics Engineering Energy Materials Science & Nanotechnology Physics

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Pengaruh Temperatur terhadap Karakterisasi Klinker Semen dengan Substitusi 20% Batu Basalt terhadap Massa Batu Kapur dan 20% Batubara terhadap Massa Total sebagai Reduktor Leni Rumiyanti; Yuliana Sari; Muhammad Amin
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.v7i1.2141

Abstract

This study was conducted to determine the effect of temperature on the chemical content and crystal structure on clinker of cement with 20% substitution of basalt stone on the mass of limestone and 20% of coal against total mass. The raw material used is basalt stone from East Lampung and anthracite coal. The percentage of limestone used is 80%. All raw materials are milled, sifted, then formed pellets with a diameter of 0.8 - 1.4 cm. Pellets are dried at room temperature, then heated and burned with temperature variations of 1000 ° C, 1100 ° C and 1200 ° C for 1 hour. XRF results showed that basalt rock had a content of SiO2 + Al2O3 + Fe2O3 of 79.293% so that basalt could be said to have pozzolanic properties. The CaO content for cement clinker decreased, the results of XRF with combustion temperatures of 1000 ° C, 1100 ° C and 1200 ° C respectively were 62,329%, 55,606%, and 54,148%. Materials A, B and C respectively were burning at 1000°C, 1100°C, and 1200oC for 1 hour. The crystalline phase formed in material A is calcium iron oxide with the highest peak belonging to Ca at position 2θ which is 26.6627° and another crystal phase, gehlenite, syn. The crystalline phase formed in material B is akermanite-gehlenite syn with the highest peak belonging to Ca at position 2θ which is 31.2747° and other crystalline phases namely and wollastonite, ferroan 1A. While the crystalline phase formed in material C is akermanite-gehlenite with the highest peak belonging to Ca at position 2θ which is 31.3051° and syn and other crystalline phases namely wollastonite, ferroan 1A.
PENGARUH KONSENTRASI INHIBITOR KOROSI EKSTRAK KULIT PISANG KEPOK (Musa paradisiaca L) TERHADAP LAJU KOROSI BAJA KARBON API 5L PADA SUHU PERENDAMAN 40OC DAN 80OC Titan Nurahman; Ediman Ginting Suka; Leni Rumiyanti
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.v9i2.2719

Abstract

Abstract. Research has been carried out on the effect of the concentration of Kepok banana peel extract as an inhibitor on API 5L carbon steel in 3% NaCl corrosive medium. API 5L carbon steel immersion was carried out for 7 hours with two variations of immersion temperature, namely 40 and 80 oC and five variations in the concentration of corrosion inhibitors, namely 0%, 2%, 4%, 6%, 8%. Corrosion rate testing was carried out using the weight loss method. The results showed that the largest corrosion rates at immersion temperatures of 40 and 80 oC were at 0% inhibitor concentrations, namely 60.91 mm / y and 86.91 mm / y. Meanwhile, the lowest corrosion rate was at the inhibitor concentration of 8% at immersion temperatures of 40 and 80 oC, namely 32.51 mm / y and 63.92 mm / y. The greatest effectiveness of corrosion inhibitors occurred at a concentration of 8% at immersion temperatures of 40 and 80 oC of 56.63%, and 26.44%. The results of the X-Ray Diffraction (XRD) characterization showed that the phase formed was pure Fe. Scanning Electron Microscopy (SEM) characterization showed uneven clusters and smaller size, holes and cracks were also less in 8% inhibitor at immersion temperature of 40 and 80 oC compared to inhibitor 0% at immersion temperature 40 and 80 oC.
Pengujian Gugus Fungsi Silika Berbasis Sekam Padi Dengan Variasi Suhu & Konsentrasi Cetyltrimethylammonium Bromide Sebagai Bahan Baku Mesoporous Silica Leni Rumiyanti; Catur Destiana; Ria Oktaviani; Simon Sembiring; Syafriadi Syafriadi; Ni Luh Gede Ratna Juliasih
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.v9i2.2727

Abstract

Research has been conducted to test silica function groups based on rice husks with temperature variations and concentrations of Cetyltrimethylammonium Bromide as raw materials for mesoporous silica. In this study, rice husk silica was synthesized by alkaline method with variations in CTAB concentrations of 2.0%, 2.5%, 3.0%, 3.5%, and hydrothermal treatments with temperature variations of 120, 130, 145, and 160ºC for 1 hour in an autoclave. Fourier-Transform Infrared (FTIR) results showed the presence of the most dominant clusters, namely Si-O-Si and other groups such as C-H, -H, O-H, and –OH. Therefore, silica-based rice husks can be used as raw materials mesoporous silica
Synthesis of Superconductor Bi1,6Pb0,4Sr2Ca2Cu3O(10+x) for Meissner Test Demonstration Using Solid Reaction Method Liyana Mardova; Amilia Rasitiani; Dwi Asmi; Leni Rumiyanti; Sigit Dwi Yudanto
Jurnal Teori dan Aplikasi Fisika Vol 8, No 2 (2020): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v8i2.2592

Abstract

The research has been done in the field of Field Work Practice to synthesize superconductors Bi1,6Pb0,4Sr2Ca2Cu3O10+x for Meissner test using solid reaction method. The objective of this research is to make superconductor Bi1,6Pb0,4Sr2Ca2Cu3O10 x with solid reaction method and to know the result of superconducting character of Bi1,6Pb0,4Sr2Ca2Cu3O10 +x based on Meissner test. From the results of Meissner test that has been done on this superconductor sample looks super magnet and superconductor repel each other rejects or super magnet drift.Sehingga it can be concluded that the sample has a strong Meissner effect. From the results of Tc test using cryogenic tools obtained Tc Zero temperature of 103.4 K and Tc Onset of 116.67 K. From the data obtained it can be concluded that the sample has reached phase 2223.
Skrinning Fitokimia Ekstrak Daun Sirsak (Annona muricata) Dan Pengaruhnya Terhadap Laju Korosi Baja Karbon ST 37 Leni Rumiyanti; Amilia Rasitiani; Ediman Giting Suka
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.v7i1.1917

Abstract

Research has been conducted on a phytochemical screening of soursop leaf extract (Annona muricata) and its effect on the corrosion rate of ST 37 carbon steel. Extraction of soursop leaves was carried out by the maceration method, while corrosion rate testing was carried out by weight loss method. ST 37 carbon immersion was carried out for 10 days with 7 variations of concentration, namely 0%, 5%, 10%, 15%, 20%, 25%, 30%, and 35%. The results of phytochemical screening showed that the soursop leaf extract contained saponins, triterpenoids, tannins, alkaloids, and flavonoids. The greatest corrosion rate was obtained at a concentration of 0%, which was 1.3 x 104 mm / y, while the lowest corrosion rate was at a concentration of 30%, which was 0.032 x 104 mm / y. The greatest corrosion inhibition efficiency occurred at a concentration of 35% at 97.53%. Based on the results of the reaserch, it can be concluded that the higher the concentration of soursop leaf extract used, the lower the corrosion rate and the higher the inhibition efficiency of the corrosion
OPTIMIZATION OF THE USE OF FLY ASH AS AN ADDITIVE PORTLAND COMPOSITE CEMENT (PCC) Leni Rumiyanti; Listiani Listiani; Tika Damayanti
Spektra: Jurnal Fisika dan Aplikasinya Vol 4 No 2 (2019): SPEKTRA: Jurnal Fisika dan Aplikasinya, Volume 4 Issue 2, August 2019
Publisher : Program Studi Fisika Universitas Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (336.915 KB) | DOI: 10.21009/SPEKTRA.042.02

Abstract

Research has been carried out on the optimization of the use of Lahat Fly Ash as an Additive Portland Composite Cement (PCC) which aims to determine the optimum conditions for adding Lahat fly ash to produce cement with physical and chemical requirements in accordance with SNI 7064:2014 and discover the ideal composition of cement with fly additions Lahat ash from various cement compositions. The quality analysis in making PCC cement is chemically in the form of Insoluble Residue (IR), Loss of Ignition (LOI), and free lime (FCaO) as well as the quality of physics in the form of Blaine, setting time, and cement mortar compressive strength. The results obtained after the process of making PCC cement with the addition of 14% Lahat fly ash, namely PCC cement in optimum conditions with physical and chemical requirements in accordance with SNI 7064: 2014 where the ideal composition of PCC cement manufacture is 14% Lahat fly ash, clinker 62%, 3% gypsum, 18% limestone, and 3% pozzolans in making PCC cement. Therefore, Lahat fly ash can be used as an alternative mixture in making PCC cement.
Co-Authors Amilia Rasitiani Catur Destiana Dwi Asmi Ediman Ginting Suka Ediman Giting Suka Listiani Listiani Liyana Mardova Muhammad Amin Ni Luh Gede Ratna Juliasih Ria Oktaviani Sigit Dwi Yudanto Simon Sembiring Syafriadi Syafriadi Tika Damayanti Titan Nurahman Yuliana Sari