Ketut Sofjan Firdausi, Ketut Sofjan
Departemen Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro, Semarang

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DETERMINATION OF RELATIVE DISSOCIATION ENERGY FROM ELECTRO-OPTICS AS A NEW SINGLE-PROPOSED PARAMETER OF VEGETABLE OIL QUALITY Firdausi, Ketut Sofjan; Afiefah, Izzah; Sugito, Heri; Septianti, Ririn Widya; Richardina, Very; Soesanto, Qidir Maulana Binu; Azam, Much
Journal of Physics and Its Applications Vol 2, No 1 (2019): November 2019
Publisher : Diponegoro University Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i1.5181

Abstract

In this report, we study the electro-optics effect on cooking oil to obtain the relative dissociation energy as a new single proposed parameter of oil quality. The sample was canola oil which had been heated in 0.5 hours, 2 hours and 4 hours. The light source used in the experiment was a green pointer laser with a wave length of 532 nm. The sample was applied to a potential difference from 0 to 9 kV to obtain the electro-optics effect in form of the change of the polarization angle Dq as function of potential difference DV. The relative dissociation energy was obtained from the fitting data of the relative Lenard-Jones potential energy curves represented by change of polarization per unit change of potential difference, Dq/DV. The result shows that the relative dissociation energy is reduced as the oil quality decreased after heated. The relative dissociation energy provides simple physical understanding about electro-optics effect on cooking oils. The study of electro-optics polarization that represents relative Lenard-Jones potential energy is a new but somewhat intuitive, which can be further improved and emphasized for grouping, mapping, and determining various cooking oil quality and halal food due to the lard contamination.
METODE POLARISASI TRANSMISI UNTUK DETEKSI CEMARAN LEMAK BABI PADA MINYAK GORENG Putri, Nidia Kharisma; Firdausi, Ketut Sofjan; Sugito, Heri
YOUNGSTER PHYSICS JOURNAL Vol 6, No 4 (2017): Youngster Physics Journal Oktober 2017
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

This study was conducted to search for "fingerprint" of the existence of lard in vegetable  oil contaminated by lard as an evaluation of the halal of cooking oil by using transmission polarization method. The sample used was palm oil that has been mixed with chicken oil and lard. The light source used was green laser with wavelenght 532 nm. Measurement was conducted based on change of polarization transmission angle, with addition of external electric field produced by two parallel plates connected to 0-6kV DC voltage. The result shows that contaminated palm oil has greater polarization angle changes than pure palm oil. And  palm oil that has been contamined by lard has the greatest polarization angle than a pure palm oil and palm oil contaminated by chicken oil. Transmisson polarization method can be used to evaluate halal of cooking oil.Keywords: Polarization, Electrooptics,Cooking oil, Halal
PENGUKURAN PERUBAHAN POLARISASI PADA AIR BERAS MENGGUNAKAN HAMBURAN MIE Wahyuni, Wahyuni; Firdausi, Ketut Sofjan
YOUNGSTER PHYSICS JOURNAL Vol 5, No 4 (2016): Youngster Physics Journal Oktober 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

Have been done scattering studies of rice water using polarization method with the light sources is a green laser with a wavelength of 532 nm and variations of the density of rice water. The test samples consist of three kinds of rice water obtained from different rice tipes.Change of scattering polarization direction is perpendicular to the incident light. Then observed the changes of scattering polarization angle seen in analyzer. The result showed that the scatttering polarization angle changes produced by the green laser in the rice water is increased to the amount of rice water particles. Then changes of scattering polarization angle in qualitative influenced by the size of rice water particles.
PENGUKURAN PERUBAHAN SUDUT POLARISASI OLEH FLUORESENSI PADA SAMPEL MINYAK ZAITUN Simbolon, Nyadaniati; Firdausi, Ketut Sofjan
YOUNGSTER PHYSICS JOURNAL Vol 5, No 4 (2016): Youngster Physics Journal Oktober 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

The aim of this research is to show how the quality difference of cooking oil affect polarization angle changes of fluorescence. The fluorescence could be usefull to identify quality of matter according to colour changes. In this research, to identify fluoresence polarization changes edible and expired olive oil used as sample with different expired date. To produce fluorescence, a green laser with wavelength 532 nm pass by polarizer and produce polarized light. Analizer sets perpendicular to polarization plane. The result show that quality difference affect the fluorescence polarization changes. The worst quality of oil the higher polarization changes. Smallest polarization changes we get in the best quality edible olive oil as 50,90 and 61,60 for the expired one.
ANALISIS KUALITAS MINYAK GORENG BERDASARKAN NILAI GRADIEN PERUBAHAN SUDUT POLARISASI MENGGUNAKAN METODE ELEKTROOPTIS Ekasari, Ekasari; Firdausi, Ketut Sofjan
YOUNGSTER PHYSICS JOURNAL Vol 5, No 2 (2016): Youngster Physics Journal April 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

Palm cooking oil quality testing has been done using natural polarization and electro-optics. Tests conducted to determine the quality of oil based active optical properties of the oil. The addition of external electric field aims to get the value of the polarization angle changes each brand oil. Oil samples were tested in the form of palm oil with a variety of brand new and has ditreatmen oil for frying foodstuffs. Test parameters after the addition of external electric field gradient that is of value elektrooptis. The test results, samples of oil to the value of large polarization angle gradient changes indicated have relatively low quality. Instead gradient small polarization angle, indicating high quality oil. Elektrooptis smallest gradient value of 0,51o/ kV, while the largest gradient value is 0,68o / kV. Keywords: polarization, elektrooptis, oil quality
LEARNING VECTOR QUANTIZATION PADA PENGENALAN POLA TANDATANGAN Mubarika, Sofia; Munir, M.; Firdausi, Ketut Sofjan; Widarto, Widarto
JURNAL SAINS DAN MATEMATIKA Volume 14 issue 4 Year 2006
Publisher : JURNAL SAINS DAN MATEMATIKA

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ABSTRACT---In this paper, we analyze and compute distribution of thermal neutron flux in core of Kartini?s Reactor using ?Swadaya? detector, both for axial (function of z) and radial (function r) direction. First, ?Swadaya? detector is calibrated by activation plate method, which the output from detector is current. The result of calibration is thermal neutron flux (?) dependent on current (I) that can be written as ? = 4,57x1020I - 2,74x1011. Distribution for neutron thermal flux for axial direction and radial direction respectively ? = 5,10 x 1012 + 5,99 x 1013 and ? = 1.08 x 1012 + 1,00 x 103 which in reactor core ? has largest value in center position for radial direction.   Keywords: flux neutron distribution, nucleus reactor, Swadaya detector
Mapping Various Cooking Oil using Fluorescence Polarization Firdausi, Ketut Sofjan; Afiefah, I.; Sugito, Heri; Azam, Much.
Journal of Physics and Its Applications Vol 1, No 1 (2018): November 2018
Publisher : Journal of Physics and Its Applications

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1675.834 KB) | DOI: 10.14710/jpa.v1i1.3913

Abstract

In this report we have succeeded to map various cooking oils using change of fluorescence polarization. Various cooking oils consisted of several vegetables oils and animal oils (chicken oil and lard) were used in the experiment, and some oils were measured in two different times. The change of polarization angle &tetha; was measured as the difference between linear polarized green pointer laser as incoming light and fluorescence light using a pair of polarizers. The direct measurement of fluorescence polarization gives a new unique result of critical polarizer’s angle φc that can group vegetable cooking oils into group 1 (at φc = 10o for VCO, olive, and soybean), group 2 (at φc = 20o for palm, corn and rice bran), group 3 (at φc = 30o for sunflower and canola), and also animals cooking oils into group 4 (at φc = 20o for chicken oil), and group 5 (at φc = 40o for lard). Mostly cooking oils can be distinguished using modified maps. The large difference φc and &tetha; of lard from vegetable oils provides an advantage to develop for testing halal oil due to lard contamination. The capability of this method has benefits, at least, as a complement and simple method in comparison to other expensive sophisticated instruments such as fluorescence spectroscopy or GCMS methods with their derivation’s instruments.
STUDI POLARISASI FLUORESENSI MENGGUNAKAN SAMPEL MINYAK SAWIT Febriyanto, Aziel Nimrod; Firdausi, Ketut Sofjan
YOUNGSTER PHYSICS JOURNAL Vol 5, No 4 (2016): Youngster Physics Journal Oktober 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

This study was conducted to compare the changes in fluorescence polarization angle for fresh cooking palm oil, expired or used cooking oils with electrooptic method. The samples are one brands with a variety of palm cooking oil expired, two fresh palm cooking oil samples and two samples of used cooking oil. Used a green laser with a wavelength of 532 nm as light source. The results showed that most small changes in polarization angle experienced by the samples of fresh oil then becomes greater for expired and used cooking oil samples. The biggest polarization angle changes occur in used cooking oils and oil expired that shows the low quality of the sample. The results showed that the polarization by fluorescence is possible to be used as a complementary test oil quality parameter.
PENGUKURAN SIFAT OPTIS AKTIF BAHAN NAFTALENA DAN ANTRASENA DALAM MEDAN LISTRIK LUAR Inayat, Fajri; Firdausi, Ketut Sofjan
YOUNGSTER PHYSICS JOURNAL Vol 5, No 4 (2016): Youngster Physics Journal Oktober 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

Naphthalene (C10H8) and anthracene (C14H10) are simetric organic matter. Both of them predicted didn?t have electrooptic characteristic. That characteristic will appear if we induce them with external electric field. In the examination, it was used source light incandescent lamp 100 W. The external electric field generated by HV DC generator of 0-7 kV. The electrooptics characteristic was determined by measuring the change of polarization angle of light as it passed through the difference concentration of naphthalene and anthracene while they were applied by external electric field.Based on the result of observation,  change of polarization angle of the light was increasing at each different potential between naphthalene (range 0,30 ? 10) and anthracene (range 0,10 - 0,70). Beside that, changes of polarization angle of the light was increase linearly to the increase of naphthalene concentration, while anthracene was not. These results consider for more research to do with alternative organic materials in photonic devices.
STUDY OF THE MOST RESPONSIBLE PARAMETERS ON POLARIZATION FOR POWERFUL PRELIMINARY TEST OF OIL QUALITY Firdausi, Ketut Sofjan; Suryono, Suryono; Priyono, Priyono; Muhlisin, Zaenul
YOUNGSTER PHYSICS JOURNAL Vol 7, No 2 (2018): Youngster Physics Journal April 2018
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

In this study, the most responsible parameters on polarization in total natural vegetable oils and fats have been investigated by determination of the relation between the polarization change and fatty acids (FA) composition. The change of light polarization was simply measured by using a pair of polarizer-analyser to indicate oil quality level, and the FA composition was obtained by using Gas Chromatography and Mass Spectrometer (GCMS) method. Various vegetable oils and fats were examined without any preliminary treatments. The experimental condition of the samples during measurement was assumed to be constant. It has been shown that various oils and fats have different angle of change of polarization, which indicates various oil quality level relative to each other, in agreement to the previous works. Especially for vegetable oils, high change of polarization has been considered as low quality of oil. The long chain of saturated fatty acids (SFA) and unsaturated fatty acids (UFA), which are distributed at third position (R3) and first position (R1) of triglycerides (TG) molecules, are responsible for the change of polarization and presented as a linear combination of the number of SFA or UFA. The result shows that the polarization could be used as powerful method for preliminary detection of oil quality level. The highest number of coefficient of C19:0 in lard indicates that this method has provided good prospect to evaluate the halal level of oil due to lard contamination.Keywords?polarization, triglyceride (TG), saturated fatty acid (SFA), unsaturated fatty acids (UFA)