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Perubahan Struktur Kristal Fase (Gd1-xLax)Ba2Cu3O7-δ dengan x Made Sumadiyasa; Nyoman Wndri; Ni Nyoman Rupiasih
Jurnal Fisika Indonesia Vol 21, No 3 (2017)
Publisher : Department of Physics Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (494.399 KB) | DOI: 10.22146/jfi.42388

Abstract

Telah dilakukan sintesis senyawa (Gd1-xLax)Ba2Cu3O7-δ  dengan x £ 2,5. Sintesis dilakukan dengan metodereaksi padatan dengan pencampuran basah. Penelitian ditujukan untuk mengetahui perubahan struktur kisi kristal dari fase Gd1Ba2Cu3O7-δ  jika dilakukan substitusi La terhadap Gd. Hasil sintesis dikarakterisasi dengan X-Ray Diffraction  (XRD). Dengan menggunakan  software Match 3, dan Rietica diperoleh bahwa pada semua sampel telah terbentuk senyawa fase Gd1Ba2Cu3O7-δ dengan struktur kristal bersimetri orthorombik. Dari perubahan nilai parameter kisi kristalnya mengindikasikan bahwa peningkatan kandungan La mengakibatkan perubahan simetri dari orthorombik menjadi tetragonal. Dari visualisasi struktur kisi kristal dapat diamati adanya perubahan posisi dari O(2) dan O(3), yaitu dengan bertambahnya kandungan La posisi O(2) dan O(3) cenderung bergeser mendekat  ke arah kation Ba.
Pengaruh Ikat Silang Glutaraldehid Terhadap Morfologi Nanofiber Komposit PVA/Chitosan/Kolagen Ria Yuliani; Dewa Ayu Sukma Pranastia; Ni Nyoman Rupiasih; I Wayan Supardi; K N Suarbawa
BULETIN FISIKA Vol 25 No 1 (2024): BULETIN FISIKA February Edition
Publisher : Departement of Physics Faculty of Mathematics and Natural Sciences, and Institute of Research and Community Services Udayana University, Kampus Bukit Jimbaran Badung Bali

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/BF.2024.V25.i01.p08

Abstract

Salah satu teknik untuk meningkatkan stabilitas nanofiber komposit PVA/kitosan/kolagen (PChK) dalam air adalah dapat dilakukan melalui ikatan silang dengan glutaraldehid (GA). Berkaitan dengan hal tersebut, tujuan dari penelitian ini adalah untuk mengetahui pengaruh ikatan silang GA terhadap morfologi nanofiber komposit PChK. Nanofiber komposit yang digunakan adalah P8Ch2K2, P8Ch2K4, dan P8Ch2K8. Larutan yang digunakan dalam ikatan silang ini adalah larutan Aseton:GA:HCl dengan rasio 9:1:0,01 dan waktu reaksi ±4 jam. Karakterisasi nanofiber dilakukan dengan SEM dan dianalisis menggunakan ImageJ dan Origin. Diperoleh bahwa nanofiber ikat silang GA memiliki diameter serat rata-rata lebih besar yaitu dengan peningkatan rata-rata 7,54% dan panjang serat lebih kontinu yaitu dengan peningkatan panjang rata-rata 42,06%, dibandingkan dengan nanofibers tanpa ikat silang GA.
THE EFFICACY OF CHITOSAN FROM WINDU SHRIMP SHELLS AS A PRESERVATIVE OF FRESH KENYAR FISH IN THE FORM OF DARNE DURING STORAGE AT ROOM TEMPERATURE Ni Nyoman Rupiasih; Yosefa Yakunda Tandu; Nyoman Wendri; S. S. Jagtap
Jurnal Neutrino:Jurnal Fisika dan Aplikasinya Vol 15, No 1 (2022): October
Publisher : Department of Physics, Maulana Malik Ibrahim State Islamic University of Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/neu.v15i1.17094

Abstract

This study is about the efficacy of chitosan from windu shrimp shells (Panaeus monodon) as a preservative for fresh fish in the form of darne (steak), namely fresh kenyar fish (Sarda orientalis) during storage at room temperature. The chitosan solution used are chitosan solution with concentration of 1%, 1.5%, 2%, and 2.5%. The fish samples which soaked in that solutions are named T1, T2, T3, and T4, respectively .. The soaking time were 20, 40 and 60 minutes. As control were fish without treatment (C-0) and fish soaked in acetic acid (C-A). All samples stored at room temperature. The activity of chitosan as fish preservative was analyzed through pH and antimicrobial test. The pH test were made in the range of 0, 24, 48 and 72 h. The antimicrobial test was done on the storage period 24 h. The results showed that the greater the concentration of chitosan solution, the shorter the soaking time required to obtain the benefits of chitosan as an antimicrobial agent for fish preservation, especially kenyar fish in the form of darne. The fish that are still suitable for consumption for 24 hours of storage are fish that are soaked in a 2.5% (T4) chitosan solution at either 20, 40, or 60 minutes of soaking time.
EFFECT OF COLLAGEN CONCENTRATION ON MORPHOLOGY OF PVA/CHITOSAN FIBERS MADE BY ELECTROSPINNING METHOD Ni Nyoman Rupiasih; Dewa Ayu Sukma Pranastia; Made Sumadiyasa; P. B. Vidyasagar
Jurnal Neutrino:Jurnal Fisika dan Aplikasinya Vol 15, No 2 (2023): APRIL
Publisher : Department of Physics, Maulana Malik Ibrahim State Islamic University of Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/neu.v15i2.17665

Abstract

The purpose of this study was to determine the impact of the addition of collagen concentration on morphology of PVA/chitosan nanofiber. The research was conducted by making 10% PVA solution, 2% chitosan solution, and collagen solutions with various concentrations of 2%, 4%, and 8%. The PVA/chitosan/collagen nanofibers were made with ratios of 8:2:2, 8:2:4, and 8:2:8 and were named P8/Ch2/C2, P8/Ch2/C4, and P8/Ch2/C8. As a control was PVA/chitosan with a ratio of 8:2, which was named P8/Ch2/C0. The nanofiber was made by electrospinning method with the following parameters: a voltage of 10 kV, a distance from the spinneret tip to the collector of 10 cm, and a flow rate of 1.00 µl/h. Nanofiber characterization was carried out using FTIR and SEM. SEM images were analyzed using ImageJ and Origin to measure the diameter and length of the fibers. It obtained that, the best ratio of PVA/chitosan/collagen to make a good nanofiber is 8:2:2, with the characteristics are the least number of beads and solution droplets, the most continuous fiber, and the average diameter is 145.55±8.64 nm. This result showed that, the addition of collagen can improve the morphology of PVA/chitosan nanofibers, where the characteristics of fibers made depending on the concentration of collagen added.
Metoda Kalibrasi Sensor Perak Kapasitif Berbasis Mikrokontroler ATmega328 Sebagai Alat Ukur Beda Potensial Membran A. A. N. Surya Mahendra Putra; Ni Nyoman Rupiasih; I Wayan Supardi
BULETIN FISIKA Vol 25 No 2 (2024): BULETIN FISIKA
Publisher : Departement of Physics Faculty of Mathematics and Natural Sciences, and Institute of Research and Community Services Udayana University, Kampus Bukit Jimbaran Badung Bali

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/BF.2024.v25.i02.p11

Abstract

In making a measuring instrument, especially an electronics-based measuring instrument, it is necessary to calibrate the instrument made with a standard instrument while also knowing its measurement characteristics. In this study, a potential difference measuring instrument that was made using a silver capacitive sensor based on an ATmega328 microcontroller was calibrated using a standard reference electrode, namely Hanna HI 5414. The instrument was tested using a chitosan membrane and KCl solution. From the sensor calibration, an equation was found, namely Y = 0.9935 X + 0.0001 and has been converted to the ATmega328 microcontroller. The test results show that the accuracy of the measuring instrument reaches 99.82% with a measurement time of ± 3900 s faster than the standard instrument.
Biosintesis Dan Karakterisasi Nanopartikel Perak Menggunakan Ekstrak Rimpang Rumput Teki (Cyperus rotundus L.) Rosvita Hilbrida Sulastri; I Wayan Supardi; Ni Nyoman Rupiasih; I Gde Antha Kasmawan; I Gusti Agung Putra Adnyana; I Nengah Sandi
BULETIN FISIKA Vol 25 No 1 (2024): BULETIN FISIKA February Edition
Publisher : Departement of Physics Faculty of Mathematics and Natural Sciences, and Institute of Research and Community Services Udayana University, Kampus Bukit Jimbaran Badung Bali

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/BF.2024.V25.i01.p14

Abstract

Silver nanoparticles (AgNP) have been successfully synthesized using the rhizome extract of nutgrass (Cyperus rotundus L.). The method of synthesizing nanoparticles using biological materials, both microorganisms and plants, is called biosynthesis. The variation in the ratio of AgNO3 solution and nutgrass rhizome extract in units of µL and mL were 2:10, 5:10, 10:10, 15:10, 20:10, and 30:10, respectively. The process of forming silver nanoparticles was observed and characterized by UV-Vis spectrophotometer, FTIR, and SEM. The synthesis ratio that gives optimal result is 20 µL : 10 mL. The obtained silver nanoparticles have characteristic including Surface Plasmon Resonance (SPR) wavelength of 456.50 nm and random-shaped particles with an average size of 31-40 µm. The function groups formed include O-H with a peak around 3456.59 cm-1, a C-H group around 2391.93 cm-1, an O=C=O group stretching around 1155.41 cm-1, and the alkene group C=C bending with a peak at around 934.55 cm-1.
Identifikasi Kandungan Logam Pada Sampel Air Dari Sumber Air Panas Alam Di Ulumbu Desa Wewo Kecamatan Satar Mese Kabupaten Manggarai Tengah Helena Idah; Ida Bagus Made Suryatika; Ida Bagus Alit Paramarta; A.A. Ngurah Gunawan; Nyoman Wendri; Ni Nyoman Rupiasih
BULETIN FISIKA Vol 25 No 1 (2024): BULETIN FISIKA February Edition
Publisher : Departement of Physics Faculty of Mathematics and Natural Sciences, and Institute of Research and Community Services Udayana University, Kampus Bukit Jimbaran Badung Bali

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/BF.2024.V25.i01.p13

Abstract

Tests have been conducted on the metal content of Calcium (Ca), Magnesium (Mg), Iron (Fe), Zinc (Zn), Copper (Cu), and Timbal (Pb), on samples of natural hot water Ulumbu Wewo Village Satar Mese Central Manggarai Regency. The research was conducted at the Joint Laboratory of the Faculty of MIPA Udayana University using Atomic Absorption Spectrometry (AAS). The data of the study showed samples of hot water from hot water bathing attractions in Ulumbu Village Wewo Satar Mese District of Central Manggarai Regency contain Ca, Mg, Fe, Zn, Cu, Pb which at each point was different. Calcium content at point 1: 1.6001 mg/L, point 2: 26.9995 mg/L. point 3: 22.3959 mg/L, point 4: 1.1805 mg/L, and point 5: 6.7990 mg/L; magnesium content at point 1: 9.8199 mg/L, point 2: 5.5111 mg/L, point 3: 3.2000 mg/L, point 4: 5.6998 mg/L, and point 5: 8.5598 mg/L; iron content at point 1: 71.8500 mg/L, point 2: 28.7231 mg/L, point 3: 14.3057 mg/L, point 4: 59.3206 mg/L, and point 5: 64.1108 mg/L; the zinc content was only found at point 1 of: 0.5423 mg/L; copper content at point 1: 1.9899 mg/L, point 2: 0.4967 mg/L, point 3: 0.5701 mg/L, point 4: 0.8975 mg/L, and point 5: 1.4201 mg/L and lead content at point 1: 2.7687 mg/L, point 2: 3.8499 mg/L, point 3: 4.4291 mg/L, point 4: 4.8486 mg/L, and point 5: 5.7186 mg/L.
Optimasi Slice Thickness dengan Nilai Signal to Noise Ratio dan Contrast to Noise Ratio untuk Meningkatkan Kualitas Citra MRI Genu Anastasia Victor, Agnes Maria Salvi; Sutapa, Gusti Ngurah; Gunawan, A. A. Ngurah; Sandi, I Nengah; Rupiasih, Ni Nyoman; Simpen, I Nengah
Kappa Journal Vol 9 No 1 (2025): April
Publisher : Universitas Hamzanwadi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29408/kpj.v9i1.29591

Abstract

Research has been conducted on the effect of slice thickness variation on the quality of Genu MRI images. This study was conducted at the Radiology Installation of Bali Mandara Hospital using primary data from Genu MRI examination results.The independent variable in this study is the variation of slice thickness values of 3, 5, and 7 mm. There were 30 patientsmeasured and the tissues analyzed were ligament, bone, fat, and noise as background using the ROI method and the segmentation results wereresults were taken at the mean value and standard deviation in the background. The difference in SNR and CNR values due to variations in slice thickness values can be tested using the Factorial Anova test. The results of this study obtained that there is an effect of slice thickness variation on SNR and CNR values that will have an impact on the quality of MRI Genu images. The greater the slice thickness value analyzed, the greater the SNR and CNR values produced and the better the image quality. In ligament tissue, the average SNR values of 3, 5 and 7 mm are 23.830; 36.594; and 50.524, respectively. In bone tissue, 191.352; 277.399, and 344.170 were obtained. In fat tissue, SNRs of 9,460, 292,022, and 367,463 were obtained. Changing the slice thickness will directly affect the SNR. It can be seen that the higher the slice thickness value given, the higher the SNR and CNR values for each tissue evaluated and the longer the scanning time required. In the slice thickness variation.