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All Journal BERKALA FISIKA SAINS DAN MATEMATIKA YOUNGSTER PHYSICS JOURNAL JITEK (Jurnal Ilmiah Teknosains) Journal of Physics and Its Applications
Ketut Sofjan Firdausi, Ketut Sofjan
Departemen Fisika, Fakultas Sains Dan Matematika, Universitas Diponegoro, Semarang
Agriculture, Biological Sciences & Forestry Astronomy Civil Engineering, Building, Construction & Architecture Computer Science & IT Earth & Planetary Sciences Materials Science & Nanotechnology Mathematics Mechanical Engineering Physics Veterinary

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Journal : BERKALA FISIKA

 1 
KORELASI POLARISASI ELEKTRO-OPTIS DENGAN KOMPOSISI ASAM LEMAK PADA MINYAK ZAITUN SEBAGAI METODE UJI ALTERNATIF MUTU MINYAK GORENG Nurhasanah, W Dewi; Sugito, Heri; Richardina, Very; Azam, Much; Firdausi, Ketut Sofjan
BERKALA FISIKA Vol 22, No 1 (2019): Berkala Fisika Vol. 22 No. 1 Tahun 2019
Publisher : BERKALA FISIKA

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Abstract

In this study the quality of olive oil which has been degraded due to heating has been tested using the electro-optical transmission polarization method. The light source used was a laser pointer with λ = 650 nm. The degradation of the quality of olive oil was measured to be based on changes in the electro-optical polarization angle, while changes in the composition of fatty acids were tested using Gas Chromatography and Mass Spectroscopy (GCMS). The results showed that the polarization angle increases in second order polynomial on the increase in voltage and linearly on the heating duration in the sample which showed a decrease in the quality of homogeneous olive oil. Assuming that the polarization change is a linear combination of the main fatty acids from olive oil, it is obtained that C19:2 and C19:0 fatty acids are the most contributing to oil quality, that is, the reduction in oil quality is indicated by increasing polarization which is accompanied by an increase in C19:0 fatty acids and a reduction in C19:2 fatty acids. Whereas specifically for electro-optical polarization, in addition to C19:2 and C19:0 fatty acids, C19:1 also appears which slightly increases polarization by increasing the fatty acid. This method can be developed further for investigation into other vegetable oils, as well as evaluating halal oil due to contamination of lard.Keywords: Electro-optical polarization, olive oil, fatty acid composition, change inpolarization angle
POLARISASI FLUORESENS PADA VIRGIN COCONUT OIL SETELAH MENGALAMI OZONASI Azzahroh, Muffaricha; Sugito, Heri; Richardina, Very; Azam, Much.; Firdausi, Ketut Sofjan
BERKALA FISIKA Vol 22, No 3 (2019): Berkala Fisika Vol. 22 No. 3 Tahun 2019
Publisher : BERKALA FISIKA

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This study investigates interaction effects between ozone and Virgin Coconut Oil (VCO) on fluorescence polarization. The ozonation time variations carried out on VCO were 30 minutes, 60 minutes and 90 minutes with ozone flow rates of 0.6L / minute. The degradation of VCO quality due to ozonation was determined by measuring changes in the fluorescence polarization angle of the light emitted by the sample, using a green laser pointer with a wavelength of 532 nm. Typical fluorescence polarization characteristics in the range of polarization angle variations from  = 0 to  = 180 are in accordance with the results of previous studies. Increasing the length of ozonation in the sample results in an increase in fluorescence polarization. The average fluorescence polarization in the range 0    180 rises linearly over the duration of ozonation, which indicates that ozone interactions are quite effective in degrading the quality of VCO. The validation results also obtained that the duration of ozonation also increases the amount of free fatty acids, however it needs to be further investigated whether the amount of free fatty acids directly contributes to fluorescence polarization. The study of interaction of ozone in solution in biophysics and also its benefits for skin therapy in medical science are very interesting to be further conducted.Keywords: Fluorescence polarization, Virgin Coconut Oil, polarization angle
REVIEW OF A SIMPLE POWERFUL POLARIZER FOR TESTING OF EDIBLE OIL QUALITY Firdausi, Ketut Sofjan; Rahmawati, Henik
BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 4 Tahun 2015
Publisher : BERKALA FISIKA

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Abstract

In this paper, we have shown that a simple pair of polarizer can be used to measure natural optical activity in total complex oil (vegetable oil and fats). A similar concept with quantum physics has been discussed to describe briefly the probability in finding a particle within certain region with the change of polarization due to the interaction light with saturated fatty acids. The light source was fluorescence lamp and the experimental condition was kept stable, i.e. constant temperature and constant humidity. The angle of polarization was measured repeatedly until 50 times. Our relative uncertainty measurement has been obtained up to 5% and this is obviously clear to be able to differentiate various different quality of oil. More important result is that ordinary light polarization can be used as powerful test to show various quality level of oils better than recent standard methods. A good prospect has also been obtained for halal level testing. It is found that average value of polarization in lard (pig oil) is relatively higher than the others.Keywords: polarization, oil quality, saturated fatty acid
PENGEMBANGAN KARAKTERISTIK OPTIS PADA LARUTAN PERAK KOLOID MENGGUNAKAN METODE ELEKTRO-OPTIS Tiwiyaningsih, Tiwiyaningsih; Rahmawati, Aidah; Nurhasanah, Wahidatun Dewi; Richardina, Very; Khumaeni, Ali; Firdausi, Ketut Sofjan; Sugito, Heri; Soesanto, Qidir Maulana Binu; Azam, Much
BERKALA FISIKA Vol 23, No 1 (2020): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

In this paper we present a new development of optical properties on colloidal silver solutions using electro-optics effect. Samples of silver nanoparticles (NPP) were obtained by ablation method and then diluted in water to obtain various concentrations. To obtain optical characteristics of colloidal silver solutions through the electro-optical effect, the changes in the polarization of light was measured as the sample was applied by high external potential difference. The light source used was laser pointer with  = 650 nm. The results show that the colloidal silver solution shows non-linear active optical properties with increasing concentration and at a concentration of 4.6 ppm maximum natural polarization occurs. In the case of electro-optics, a voltage increase results in electro-optical contributions which correspond to the effects of non-linear polarization due to high electric fields. However, at 8 kV the maximum polarization appears also at a concentration of 4.6 ppm, which is the same as the natural polarization at that concentration. The study of colloidal silver solutions is very interesting to be further developed by electro-optical methods, because challenges and unanswered phenomena can contribute or alternative perspectives in understanding the interaction of light with matter, especially colloidal silver solutions, and the like.
Co-Authors Ahmad Kamil Ali Khumaeni Aziel Nimrod Febriyanto Azzahroh, Muffaricha Ekasari Ekasari Fajri Inayat Henik Rahmawati, Henik Heri Sugito I. Afiefah Izzah Afiefah M. Munir Maliki Maliki Michelson Fahrurazi Much Azam Much. Azam Muchammad Azam, Muchammad Nidia Kharisma Putri Nurhasanah, W Dewi Nurhasanah, Wahidatun Dewi Nyadaniati Simbolon Priyono Priyono Qidir Maulana Rahmawati, Aidah Ririn Widya Septianti S. Suryono Soesanto, Qidir Maulana Binu Sofia Mubarika Haryana Syifa Azahra Tiwiyaningsih, Tiwiyaningsih Ulfa Maftukhah Very Richardina Very Richardina Wahyu Setia Budi Wahyuni Wahyuni Winarno Winarno Zaenul Muhlisin