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Influence of Nd Substitution for Ca on Formation of 2223 Phase in the Superconductors (Bi,Pb)-Sr-Ca-Cu-O System: (Bi1.4Pb0.6)Sr2(Ca2-xNdx)Cu3O10+δ M . Sumadiyasa Sumadiyasa
Jurnal ILMU DASAR Vol 8 No 1 (2007)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

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Abstract

The influence of Nd substitutions for Ca on formation of 2223 phase in the superconductors (Bi,Pb)-Sr-Ca-Cu-O system : (Bi1.4Pb0.6)Sr2(Ca2-xNdx)Cu3O10+δ has been studied. Samples were made by solid state reaction methods, with sintering temperature at 860oC for 40 hours continuously in air atmosphere. From the XRD characterization it is revealed that the samples are poly crystals and the volume fraction of Bi-2223 phase is less than 45%. All of samples show Meissner effect weakly on 77 K, which is indicate that in the samples has formed few superconducting high-Tc phase. This result is in accords with of the resistivity as function of temperature measurement, show that the Tcon-set at 88 K - 107 K, which is range of the critical temperature (Tc) of the Bi-2212 phase and Bi-2223 phase. 
Pengaruh Suhu Sintering terhadap Pembentukan Senyawa Gd0,95La0,05Ba1,95Sr0,05Cu3O7-? Asni Mulyati Jeni; Made Sumadiyasa; Ida Bagus Made Suryatika
BULETIN FISIKA Vol 24 No 1 (2023): 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.2023.v24.i01.p02

Abstract

Telah dilakukan penelitian variasi suhu sintering antara 900 ºC – 950 ºC selama 12 jam pada sintesis fase Gd1Ba2Cu3O7-? tersubstitusi La dan Sr dengan komposisi stoikiometri Gd0,95La0,05Ba1,95Sr0,05Cu3O7-d. Penelitian ini bertujuan untuk mengetahui pada suhu berapa senyawa Gd0,95La0,05Ba1,95Sr0,05Cu3O7-d dapat terbentuk secara maksimal. Sampel dengan komposisi Gd0,95La0,05Ba1,95Sr0,05Cu3O7-d dibuat dari bahan awal Gd2O3, La2O3, BaO, Sr2O3 dan CuO. Sampel disintesis dengan menggunakan metode reaksi padatan (solid-state reaction) dengan pencampuran basah (wet-mixing) dengan asam nitrat (HNO3) sebagai pelarut. Sampel disintering dalam bentuk pelet di dalam tungku tanpa pemberian annealing gas oksigen. Sampel hasil sintesis dikarakterisasi dengan X-Ray Difraction (XRD) dan dianalisis dengan Program Match-3. Dengan menggunakan referensi Entry number 96-153-9606, hasil analisisnya menunjukkan bahwa suhu sintering adalah berdampak terhadap pembentukan senyawa fase Gd0,95La0,05Ba1,95Sr0,05Cu3O7-d. Memperlihatkan bahwa fraksi volume bertambah seiring dengan bertambahnya suhu sintering, terutama pada suhu 930°C sampai dengan 950 °C. Fraksi volume tertinggi sebesar 75,4263 % didapat pada sampel yang disintering pada suhu 950°C. Hasil refinemen dengan metode analisis Rietveld menunjukkan fase Gd0,95La0,05Ba1,95Sr0,05Cu3O7-d yang terbentuk adalah dalam simetri ortorombik. Volume unit sel adalah cenderung meningkat seiring bertambahnya suhu sintering.
Sintesis Carbon Dot Dengan Bahan Dasar Asam Sitrat Menggunakan Metode Pemanasan Secara Berulang di Dalam Oven Microwave G. Agus Permana Putra Sujana; Made Sumadiyasa; Isnaeni Isnaeni
BULETIN FISIKA Vol 22 No 1 (2021): 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.2021.v22.i01.p05

Abstract

Abstrak – In this research, a carbon dot has been synthesized using citric acid and polyethylene by heating repeatedly in the microwave. The results of the synthesis were characterized by UV-Vis, FTIR, Photoluminescence (PL) and TRPL spectroscopy. The UV-Vis characterizations show that the sample has shown two peaks with the wavelength 200-280 nm and ~330 nm. This marks the p®p* and n®p* excitation transitions which are characteristic of the carbon dot. FTIR characterization has shown the presence of O-H strain vibration bands, C=O aromatic carbonyl, C-O strain and sulfate strain vibration frequencies on wave numbers 3292, 1623, 1129 and 996 cm-1, respectively. From the PL characterization using excitation laser beams of 320, 420 and 530 nm (violet, blue and green) obtained that the carbon dot samples produced radiation emission at wavelengths of 453, 525 and 590 nm, respectively. The TRPL calculation results show that the average lifetime of the photoluminescence is in the order of 10-9 s, which is characteristic of fluorescence photoluminescence. These results show that a carbon dot has been successfully synthesized with radiadifferent emission characteristics depends on the laser beam.
Jarak Pisah Sudut Puncak Difraksi Antara Bidang (hkl) Utama Sebagai Indikator Keorthorhombikan Struktur Kisi Kristal Fase GdBa2Cu3O7-? I Komang Wahyu Surya Permana; Made Sumadiyasa; Windarjoto Windarjoto
BULETIN FISIKA Vol 22 No 1 (2021): 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.2021.v22.i01.p06

Abstract

The orthorombicity of a crystal lattice structure is indicated by the difference in lattice parameter values ??a, b and c. This study aims to show that the split distance value between the angles of the diffraction peaks of the two planes (hkl) closest is the same as the orthorombicity value crystal structure on the GdBa2Cu3O7-? phase. For this purpose, in this study, a compound Gd0,85La0,15Ba2-xSrxCu3O7- has been synthesized with variations of x = 0.00, 0.05, 0.10, 0.20, 0.30 and 0.50. Samples were synthesized using a solid reaction method with wet mixing, sintered at a temperature of 900°C for 12 hours. From the results of XRD spectrum analysis with Match-3 and Rietica software, it is found that by the increasing the content of Sr the pattern of changes in the value of the split distance the angles of the diffraction peaks of (hkl) planes closest, the measurement and calculation results are the same with the changing pattern of the orthorombicity value. The measurement and calculation results, the split distance value between the diffraction peaks angle for the plane of (020) and (200) is almost equal to one-tenth of the orthorombicity value. Thus, the split distance value between the angles of the diffraction peaks of the two (hkl) planes closest can be used as an indicator of the orthorombicity a GdBa2Cu3O7-? phase crystal structure.
PEMANFAATAN KOTORAN SAPI SEBAGAI BAHAN BIOGAS SKALA RUMAH TANGGA ANGGOTA SUBAK BANYUMATI DESA UMA ANYAR SERIRIT BULELENG P. Suardana; M. Sumadiyasa; W. G. Suharta; A. A. Ngr. Gunawan; K. N. Suarbawa
Buletin Udayana Mengabdi Vol 16 No 1 (2017)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat

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Abstract

Telah dilakukan sosialisasi kepada anggota masyarakat Subak Banyumati Desa Uma Anyar mengenai dampak yang diakibatkan oleh polusi gas metana yang dihasilkan dari kotoran sapi dan telah melakukan usaha pemberdayaan anggota masyarakat Subak Banyumati untuk mengembangkan sistim pertanian terintegrasi antara pertanian, peternakan, dan pemanfaatan teknologi untuk meningkatkan nilai tambah kotoran sapi melalui pelatihan “Pemanfaatan Kotoran Sapi Sebagai Bahan Biogas Skala Rumah Tangga”. Dengan terlaksananya program pengabdian masyarakat ini anggota masyarakat Subak Banyumati mampu membuat instalasi biogas skala rumah tangga hingga menghasilkan gas metana dan mengoprasikannya untuk memasak. Dengan demikian masyarakat Desa Ume Anyar pada umumnya dan anggota masyrakat Subak Banyumati pada khususnya mampu memanfaatkan kotoran sapi sebagai bahan biogas dan mampu membuat pupuk kompos dalam waktu yang lebih cepat dari sebelumnya, serta yang tidak kalah pentingnya adalah masyarakat berkontribusi mengurangi polusi udara oleh gas metana.
SINTESIS FASE Nd1Ba2Cu3O7-d DENGAN Ba(OH)2.8H2O SEBAGAI PENGGANTI Ba2CO3 DENGAN METODA REAKSI PADATAN DENGAN MEDIA PENCAMPUR ALKOHOL I Gede Astina; M. Sumadiyasa; I N. Artawan; W. G. Suharta
BULETIN FISIKA Vol 15 No 2 (2014): 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

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Abstract

The phase of Nd1Ba2Cu3O7-? has been synthesized by replacing Ba2CO3 to Ba(OH)2.8H2O. Thesynthesis has been done by solid reaction method in air atmosphere without annealing. The sampleswere mixed with alcohol partially and otherwise. The characterization using x-ray radiation (XRD), thatthe samples have shown the diffraction pattern appropriated to the pattern of diffraction of theNd1Ba2Cu3O7 phase with the volume fraction greater than 93% are resulted. The refinement with thesoftware Rietica procedure shown the Nd1Ba2Cu3O7 phase in symmetry orthorombyc form and the valueof c2 is less than 1.8 only on the Ba(OH)2.8H2O sample through the calcination process are produced.The superconductivity at temperatures >77K through the Meissner effect characterization andmeasurements of resistivity as in the temperature function on the sample are not arose. Since therequired oxygen content not enough to the formation of Nd1Ba2Cu3O7 phase in high-Tc. This is shown bythe crystal structure of the Nd1Ba2Cu3O7 phase in the symmetry orthorombic-II and thetragonal areformed.
PENGARUH TEMPERATUR LARUTAN TERHADAP KARAKTERISTIK RAPAT ARUS-BEDA POTENSIAL MEMBRAN KITOSAN Angelia Bella Kusumaningtyas; Ni Nyoman Rupiasih; Made Sumadiyasa
BULETIN FISIKA Vol 17 No 2 (2016): 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

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Abstract

The study about the characteristics of the diffusion current density-potential (J-V) of chitosan membrane has been done. It aims to determine the effect of concentration (C) and temperature (T) solution to J-V characteristic curve of the membrane. The membrane made of chitosan, as the base material (matrix) and 1% acetic acid as the solvent, with the composition of matrix/solvent of 2%. In the ion transport experiments, KCl electrolyte solution with various concentration of 0.1 mM, 1 mM, 10 mM, 100 mM, and 1000 mM and with variation of temperature of 300.9 to 340.9 K. The results showed that the value of the diffusion current density of ion sincreases with increasing the ratio of the concentration of solution in room 1 (C1) and room 2 (C2). The J-V curve shows non-linear relationship and it’s shifted toward larger potential with increased in temperature. These results indicate that the concentration gradient and temperature greatly affect the J-V characteristics of chitosan membrane.
PENGARUH WAKTU PAPARAN RADIASI UV-C TERHADAP KARAKTERISTIK RAPAT ARUS DIFUSI ION PADA MEMBRAN KITOSAN Putu Ika Paramitha Putri; Made Sumadiyasa; Ni Nyoman Rupiasih
BULETIN FISIKA Vol 17 No 1 (2016): 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

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Abstract

It has conducted research about the effects of UV-C irradiation to the current density of ion diffusion characteristics of chitosan membranes. A series of chitosan membranes with various ratios of components was used such as 1%, 2%, 3% and4%, the electrolyte solution was NaCl with various concentration of 0.1 mM , 1 mM, 10 mM, 100 mM, and 1000 mM, and time exposure of 5, 15, 30, and 60 minutes. Ion transport processes were carried out in a cell membrane model which composed of two compartments, and the potential difference was measured using a pair of Activon AEP calomel electrodes. All the measurements were conducted at room temperature of about 28.1oC. The result showed that the current density increased with increasing some parameters e.g. the ratio of concentration of solution in both compartments (C1/C2), the amount of chitosan (1%, 2%, 3% and4%), and exposure time.
Analysis of Superconductor of Nd1Ba2Cu3O7 and Nd3Ba5Cu8O18 Phases Using FTIR Spectrophotometer Putra Adnyana, IGA; Sumadiyasa, Made; Wendri, Nyoman
BULETIN FISIKA Vol 21 No 2 (2020): 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

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Abstract

I has been synthesized superconducting materials of the Nd1Ba2Cu3O7, Nd3Ba5Cu8O18 and Y3Ba5Cu8O18 phases. The study was conducted to determine whether the data from the phase Y1Ba2Cu3O7 can be used as a base to identify superconducting material of the Nd3Ba5Cu8O18 phase. Synthesis was done by solid state reaction method with initial mixing in HNO3 solution mixture with Y2O3, Nd2O3, BaCO3, and CuO, with the ratio adjusted to the stoichiometry calculation. Samples in the form of pellets with a diameter of 1.5 cm were sintered at 950 oC for 24 hours in an atmospheric environment. The FTIR measurements have been carried out with a standard KBr. The theoretical calculation spectra and vibration mode data from YBa2Cu3O7-d can be used to identify Nd1Ba2Cu3O7, Nd3Ba5Cu8O18 dan Y3Ba5Cu8O18, with peak absorption in the range of wave numbers that are almost the same, namely 400-450 cm-1, which is the four oxygen atoms O(2,3) mode, 426-439 cm-1 is the in-phase mode of oxygen atom O(2,3), and the vibrational mode of peaks O(4) is observed at 488 cm-1.
DTA-TG Analysis of Gd0.95La0.05Ba1.95Sr0.05Cu3Oy Compounds Made Sumadiyasa; I Putu Suardana; Nyoman Wendri
BULETIN FISIKA Vol 21 No 1 (2020): 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

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Abstract

The sintering temperature is played a vital role in the evolution of phase structure, microstructure, and the properties of the superconductor. In this study, the Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d phase compound has been synthesized by the wet method using HNO3 as a solvent. The samples were divided into two groups. The first sample was calcined at 400 °C for 2 hours + 500 °C for 2 hours + 600 °C for 6 hours. The second sample treated by the same process and then continued by heating at 900 °C for 15 minutes. The effect of the calcination temperature for the synthesis of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d bulks was investigated using the DTA-TG method. The results showed that the optimum reaction temperature for the formation of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d phase was 938 °C. The additional heating temperature e.g. 900 °C for 15 minutes on the calcination process can reduce the optimum formation temperature of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d compounds by 20 °C. The peritectic melting reaction temperatures of the sample without the addition of heating and with the addition of heating at temperature 900 °C for 15 minutes are 1032°C and 1035°C, respectively. The melting temperatures of both samples are 1164 °C and 1200 °C.