Jurnal Sains Materi Indonesia最新文献

{"title":"STUDY OF CERIA STABILIZED ZIRCONIA MICROSPHERES MORPHOLOGY BY SMALL-ANGLE SCATTERING AND MICROSCOPY","authors":"A. Insani, A. Patriati, N. Suparno, R. Langenati, S. Soontaranoon, Ridwan Ridwan","doi":"10.17146/JSMI.2019.20.2.5474","DOIUrl":"https://doi.org/10.17146/JSMI.2019.20.2.5474","url":null,"abstract":"STUDY OF CERIA STABILIZED ZIRCONIA MICROSPHERES MORPHOLOGY BY SMALL-ANGLE SCATTERING AND MICROSCOPY. Ceria stabilized zirconia microspheres of about 500 microns were prepared by external gelation. The morphology in nano and micro scale of the microsphere was evaluated. The nanostructure of CSZ microsphere after drying was studied by small angle neutron and x-ray scattering (SANS and SAXS). In this state, the existing of the mixture of ceria oxide and zirconia oxide was observed inside the polymer matrix. The roundness and surface properties of the CSZ microsphere were observed under the optical microscopy (OM) and scanning electron microscopy (SEM). The data showed their good size uniformity, smooth surface, but also the imperfect phase of the gelation.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"258 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132284914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE EFFECT OF CALCINATION ON MICROWAVE ABSORBING PROPERTIES OF Fe3O4/TiO2 COMPOSITE","authors":"A. Fisli, D. S. Winatapura, W. A. Adi, Y. Taryana","doi":"10.17146/JSMI.2019.20.2.5292","DOIUrl":"https://doi.org/10.17146/JSMI.2019.20.2.5292","url":null,"abstract":"THE EFFECT OF CALCINATION  ON MICROWAVE ABSORBING PROPERTIES OF Fe 3 O 4 /TiO 2 COMPOSITE. The Fe 3 O 4 /TiO 2 composites have been fabricated by simple precipitation method for microwave absorbing. The obtained powder of Fe 3 O 4 /TiO 2 which 10 % iron oxide containing were calcinated from 300 o C – 700 o C for 3 hours. The characteristic of samples was investigated by various techniques. The TEM image showed the composites form agglomeration with particles size of around 20 nm.  The all sample contents most of the anatase phase. The increasing of calcination temperature is the bigger of crystallite size. The Raman bands shift towards lower wavenumber and their full-widths at half-maximum (FWHM) of the bands decreases as the particles size increase. The measurement of the magnetic properties illustrated that the Fe 3 O 4 /TiO 2 exhibited paramagnetic behavior at room temperature. The microwave absorbing properties of the sample was measured by VNA  using frequency microwave filter in  X-band range  (8-12 GHz). The reflection loss (RL) values were calculated for thickness 1 mm of the sample. The minimum reflectivity peak value tends to decrease with the increase of the calcination temperature due to increasing the crystallite size of the particles. The lowest reflectivity value of Fe 3 O 4 /TiO 2 was occurred calcinated at 600 o C with -13.4 dB loss at 10.9 GHz, that is more 80% absorbed of the electromagnetic wave in thickness 1 mm of the sample. The microwave absorption properties the calcinated 700 o C the sample decrease due to the loss of magnetic properties of the sample. This study concluded that increase in average crystalline size, microwave absorption properties increased. However, the decrease dratisly of magnetic properties of the sample causes microwave absorption properties to decrease.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114357539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE POTENTIAL OF INDONESIAN GRAPHITE AS RDE FUEL MATRIX","authors":"D. Mustika, S. Sudirman, A. Fisli, I. Joni, M. Th.Rina","doi":"10.17146/JSMI.2019.20.2.5472","DOIUrl":"https://doi.org/10.17146/JSMI.2019.20.2.5472","url":null,"abstract":"THE POTENTIAL OF INDONESIAN GRAPHITE AS RDE FUEL MATRIX. The development plan of Ex- perimental Power Reactor (RDE) in Indonesia is non-commercial and leads to the technology type of Pebble Bed Reactor (PBR) - High Temperature Gas Cooled Reactor (HTGR). The fuel used for PBR reactors is kernel dispersed in spherical fuel elements. The matrix used in PBR nuclear fuel is graphite which functions as a neutron moderator, fuel protective material and heat conductor. Domestication of the domestic fuel matrix needs to be conducted to improve national independence. Therefore, it is necessary to do research on the potential of local graphite to be used as RDE fuel matrix. This study focused on the identification and characterization of local and commercial graphite. The results are compared with the literature, how far it is fulfilling nuclear grade graphite for PBR fuel matrix. Characterization of graphite includes phase analysis with XRD, micro- structure with SEM, surface area/porosity, impurities determination with AAS, ICP-OES and NAA, equivalent boron content, carbon content, density, particle size distribution and ash content. The characterization results show that the carbon content obtained was 87.0 ± 4.2% for local graphite and 100% for commercial graphite. Meanwhile, for the purposes of nuclear graphite it requires a carbon content of >99%. The impurity content in local and commercial graphite still does not meet the RDE fuel matrix standard. The results of XRD analysis show that the local graphite phase is the same as the commercial graphite phase, namely the 2H graphite hexagonal crystal system with the lattice group of P 63/mmc. Particle size distribution and surface area of local graphite are higher compared to nuclear graphite literature. The ash content of commercial graphite was 0.236 ± 0.029 and local graphite was 9.587 ± 0.010%. The results of this study indicate that the local graphite from the flotation still requires a further refinement process to obtain local graphite that can be used as a fuel matrix for RDE.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115036651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"UTILISATION OF SLAG POWDER FOR CEMENT SUBSTITUTION BASED ON THE COMPRESSIVE STRENGTH AND PENETRATION OF CHLORIDE IONS","authors":"Y. Amalia, S. Soepriyanto","doi":"10.17146/JSMI.2019.20.2.5446","DOIUrl":"https://doi.org/10.17146/JSMI.2019.20.2.5446","url":null,"abstract":"UTILIZATION OF SLAG POWDER FOR CEMENT SUBSTITUTION BASED ON THE COMPRESSIVE STRENGTH AND PENETRATION OF CHLORIDE IONS. The availability of waste from nickel ore smelting in the form of slag has increased, this is due to the high nickel production to meet the increasing needs for development and for compound- ing materials for construction materials. This research aims to make a paste from the mixture of Nickel Pig Iron (NPI) slag from PT Indoferro which is used as a substitute for making cement paste. The materials used in this study are cement, nickel slag, water, and zeolite. The cement paste is made with a dimension of 10 cm x 5 cm with each slag used as an amplifier on the paste with a volume variation of 15%, 30%, 45%, and 60%. Each material is weighed according to mix design then mixing the materials, after they are homogeneous, they are put into the mold and then let stand for 24 hours until the paste solidifies and hardens, after 24 hours, the paste sample is removed from the mold and treated at room temperature, after the life is qualified, the paste sample is tested. Results of the compression test show that variations of slag addition to the paste mixture giving maximum compressive strength is the 15% variant for NPI slag. The increase in compressive strength of the slag mixture paste may occur because slag contains cement compounds which can chemically react with Calcium Hydroxide (CH) com- pounds as a result of the hydration reaction of cement with water to form a Calcium Silicate Hydrate (CSH) compound from the hydration result between water and cement to increase adhesion and compressive strength on cement paste.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121976286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THERMAL DECOMPOSITION KINETICS OF LANTHANUM OXALATE HYDRATE PRODUCT TREATMENT FROM MONAZITE","authors":"Mv Purwani, Suyanti Suyanti, W. A. Adi","doi":"10.17146/JSMI.2019.20.2.5295","DOIUrl":"https://doi.org/10.17146/JSMI.2019.20.2.5295","url":null,"abstract":"THERMAL DECOMPOSITION KINETICS OF LANTHANUM OXALATE HYDRATE PRODUCT TREATMENT FROM MONAZITE . Unreacted shrinking core model variation was developed for calcination and solid thermal decomposition reaction to non catalytic gas and no gas reactants were involved. In this research, thermal decomposition of lanthanum oxalate hydrate product treatment of monazite. The parameters for modeling are the time and temperature of thermal decomposition. The time was between 0 - 150 minutes with 30 minute intervals and the temperature range between 600 – 700 o C with 100 o C intervals. Based on the experimental data it can be concluded that the most suitable model was unreacted core sphere ash diffusion controls and obtained the relation between temperature T o C with diffusion coefficient D following equation D = 0.0011 T + 0.5175 with linearity R² = 0.9561. Another possible model was the sphere reaction control and obtained the relationship between 1 / T (K) and reaction rate constant k s was k s = 48873.e -4.88 / RT with activation energy = 4.88 kJ. The relationship between time t with r c (radius of particles at time t) at various temperatures and the relation between temperature and r c at various times follows the exponential line equation. If temperature and time parameters were combined will find the relation between time and temperature with r c following the equation ln r c = -0.9536 (9E-04 T + 0.005 T) + 4.9976.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"48 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114131306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MICRO-CRYSTAL STRUCTURE OF 57Fe15Cr25Ni0.32Mn0.96Si AUSTENITE STEEL AFTER 850°C-5H TEMPERATURE-QUENCHING TREATMENTS FOR HIGH TEMPERATURE MATERIAL APPLICATIONS","authors":"P. Parikin, Rudi Rudi, S. Sumaryo, S. Ahda","doi":"10.17146/JSMI.2018.20.1.5407","DOIUrl":"https://doi.org/10.17146/JSMI.2018.20.1.5407","url":null,"abstract":"MICRO-CRYSTAL STRUCTURE OF 57Fe15Cr25Ni0.32Mn0.96Si AUSTENITE STEEL AFTER 850°C-5H TEMPERATURE-QUENCHING TREATMENTS FOR HIGH TEMPERATURE MATERIAL APPLICATIONS. A serial austenite stainless steel, namely A2-type, has been synthesized by using casting technique at temperature more than 1250 °C in the induction furnace that used an electromagnetic inductive-thermal system. The steel is dedicated for structural component material in multi-purpose applications such as in high-temperature operating environments. So, the material must be resistant to mechanical loads, high temperature, corrosion and irradiation. In order to increase the strength of materials, temperature-quenching treatments are required in some cooling media. Mineral element was extracted from crude ores of Indonesian mines and commercial scrap materials, i.e: ferro scrap, ferro chrome, nickel, manganese, and ferro silicon; all of them in granular shape were prepared to alloy the steel. Titanium was not added to this austenite low carbon steel. The OES-chemical composition in %wt of the materials is 57%Fe, 15%Cr, 25%Ni, 0.34%C and less than 0.1% of impurities that comprised of: titanium, phosphor, copper, niobium and sulphur elements in the steel. X-ray diffraction pattern shows that ascast material had an fcc crystal structure with lattice parameter of 3.632 Å. Meanwhile, two of samples, i.e: annealing and oil quench, have strictly similar lattice parameter to that of air (normalizing) quench (3.580 Å). On the other hand, the lattice parameter of water quenched samples has a slightly lower lattice parameter than the ascast lattice , i.e. 3.587 Å. The peak shift of (111) and (200) -plane in the diffraction profile, is very significant, approximately 0.63 degrees between ascast sample and the last two samples. Ascast microstructure reveals that the austenite phase grains look large and describe an undeformed structure, with an average grain size of about 6 mm, while the annealed sample was larger. Air- and oil- quenched sample microstructures showed a fine grain which was very different to water quenched sample microstructure that showed a coarse grain. The viscousity (h) of the quenching medium had an important role in the formation of grain boundary, because the rate of decreasing temperature was heavily influenced by the diffusion of heat from the high to low temperature spaces.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123874747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE EFFECT OF PRETREATMENT OF MICROWAVE HEATING ON EFFICIENCY OF HYDROLYSIS TIME AND α-CELLULOSIC CHARACTERISTICS OF PALM OIL WASTE BIOMASS","authors":"F. Kasim, Khaswar Syamsu, D. Setyaningsih, P. Suryadarma, S. Sudirman","doi":"10.17146/jsmi.2018.20.1.5408","DOIUrl":"https://doi.org/10.17146/jsmi.2018.20.1.5408","url":null,"abstract":"THE EFFECT OF PRETREATMENT OF MICROWAVE HEATING ON EFFICIENCY OF HYDROLYSIS TIME AND α-CELLULOSIC CHARACTERISTICS OF PALM OIL WASTE BIOMASS. This research is underlied by the needs of various industries for alpha cellulose, especially for the needs of raw material for cellulose nanocristalline, from fiber derived from the most potential waste biomass in Indonesia, namely oil palm empty fruit bunches (OPEFB) and mesocarp fibers. This study aims to find out the effect of pretreatment by microwave heating on the efficiency of hydrolysis time and alpha cellulose characteristics from palm oil waste biomass. To produce alpha cellulose, acid hydrolysis is commonly used with the multistage pulping process method, where the fiber is dissolved into HNO3 mixed acid, 3.5% and NaNO2, heated at a temperature of 90 oC for 2 hours, hydrolyzed and delignified to remove lignin and bleached, then separated from betha and gamma cellulose by dissolving it with NaOH 17.5%. In this study, a preliminary treatment (pretreatment) with microwave heating was carried out before the fiber was hydrolyzed so that the hydrolysis process was more efficient without reducing the characteristics of the alpha cellulose produced. The research results showed that pretreatment with microwave heating can streamline the hydrolysis time from 2 hours to 1 hour, without reducing its characteristics, where the degree of fiber crystallinity (XRD) and the yield of alpha cellulose remain high. Microwave heating with 450 watts for 5 minutes (treatment A) is better than 300 watts of heating for 10 minutes (treatment B). From the results of the study, it can be concluded that the pretreatment with microwave heating can streamline the hydrolysis time of the fiber to obtain alpha cellulose and increase the yield of the produced alpha cellulose.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"2013 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127322217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SYNTHESIS, STRUCTURAL ANALYSIS AND INITIAL ELECTRIC SCRATCHING ON PbZrXTi(1-X)O3 PIEZOELECTRIC MATERIAL","authors":"S. Ahda, M. Mardiyanto, P. Parikin","doi":"10.17146/JSMI.2018.20.1.4798","DOIUrl":"https://doi.org/10.17146/JSMI.2018.20.1.4798","url":null,"abstract":"SYNTHESIS, STRUCTURAL ANALYSIS AND INITIAL ELECTRIC SCRATCHING ON PbZrXTi(1-X)O3 PIEZOELECTRIC MATERIAL . PbZrTi(1-x)O3(PZT) material is currently one of the highest- quality piezoelectric materials and has been widely used in various applications, including as sensors in the observation system in nuclear reactor cores. In this study, a solid state reaction method was used to synthesize PbZrTi(1-x)O3(PZT) material with variations in compaction pressure of 7000 and 5000 psi. The sample synthesized was analyzed by the crystal structure system using Rietveld method of X-ray diffraction (XRD) pattern. The fitting results from Highscore program showed compounds with perovskite crystals system of tetragonal (PbZr0.52Ti0.48O3) and rhombohedral (PbZr0,58Ti0,42O3) and PbTiO3 (tetragonal). The electrifying process using an electrical voltage of kv DC has been successfully carried out on synthesis products. The voltage source used is from the electronic circuit Television (TV) 14-21 inches which has a flyback component and then continues with a voltage drop by making a voltage divider. The polling results can be identified by measuring the piezoelectric constant with the d33 meter device. Optimization of polling parameters to the material temperature was obtained at 100 oC, then applied polling sample of PbZrTi(1-x)O3(PZT) material added by PVDF (1.5, 2.5 and 5% weight percent) to samples with the compaction of 7000 and 5000 psi. Maximum d33 measurement (61 x 10-12 C/N) was obtained on PZT material with a pellet pressure of 7000 psi. Increasing the addition of PVDF results in a reduction of d33.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115246820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"APPLICATION OF SULFONATED POLYSTYRENE IN POLYMER ELECTROLYTE FUEL CELL","authors":"S. Hendrana, Erwin Erwin, Krisman Krisman, Syakbaniah Syakbaniah, Isna’im Isna’im, Yusmeri Yusmeri, Neti Satria, T. Susilawati, S. Sudirman","doi":"10.17146/JUSAMI.2018.20.1.5406","DOIUrl":"https://doi.org/10.17146/JUSAMI.2018.20.1.5406","url":null,"abstract":"APPLICATION OF SULFONATED POLYSTYRENE IN POLYMER ELECTROLYTE FUEL CELL. Sulfonated polystyrene (SPS) is polyelectrolyte solid that widely used in many aplications. In this works SPS is applied for some parts of polymer electrolyte fuel cell membrane due sulfonate group available in the structure. The investigation involve the application for membrane with addition of small molecules, i.e. benzimidazole and evaluating its microstructure and performance. Application of SPS solution as binding agent in MEA will also be presented.  The results show that when using SPS as fuel cell membrane, the additon of small molecules such as benzimidazole would modify its microstrusture as well as improve its ion conductivity. Meanwhile, some improvement still required for application of SPS solution as binding agent for preparation of Membrane Electrode Assembly or MEA.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131303772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FORMATION OF SPINEL STRUCTURE IN SYNTHESIS PROCESS OF Li1.37Mn2O4 USING HYDROTHERMAL METHOD","authors":"I. Purawiardi, E. M. Wigayati","doi":"10.17146/jsmi.2018.20.1.5405","DOIUrl":"https://doi.org/10.17146/jsmi.2018.20.1.5405","url":null,"abstract":"FORMATION OF SPINEL STRUCTURE IN SYNTHESIS PROCESS OF Li1.37Mn2O4 USING HYDROTHERMAL METHOD. Li1.37Mn2O4 is one form of Li1+xMn2O4 which is engineered from LiMn2O4 phase which is commonly used as a lithium cathode active ingredient. The crucial thing from Li1.37Mn2O4 synthesis is the spinel structure that is formed. This study aims to observe when the spinel structure of Li1.37Mn2O4 starts and when the transformation from a tetragonal structure into spinel occurs. The raw materials used are tetragonal LiOH and tetragonal MnO2. The synthesis was carried out using a hydrothermal method with a temperature of 200 oC with a variation of holding times of 50, 70, 90 and 110 hours. Observation of spinel structure was carried out using XRD and TEM. The results obtained were at the holding times of 50 and 70 hours, the spinel structure had not been formed. The spinel structure begins to form at 90 hours holding time which also indicates that the transformation from the tetragonal structure to spinel occurs at such holding time. The result of a 90-hour holding time is a regular spinel structure but there are still many Mn and Mn-O –based impurities. While the results of the 110-hour holding time produce a perfect yet irregular transformation of the spinel structure.","PeriodicalId":365391,"journal":{"name":"Jurnal Sains Materi Indonesia","volume":"13 48","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133204323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}