ORCID Profile
0000-0002-6727-9283
Current Organisation
Universitas Halu Oleo
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Publisher: IOP Publishing
Date: 09-2018
Publisher: Oriental Scientific Publishing Company
Date: 25-10-2017
DOI: 10.13005/OJC/330557
Publisher: Oriental Scientific Publishing Company
Date: 25-06-2017
DOI: 10.13005/OJC/330314
Publisher: Springer Science and Business Media LLC
Date: 14-11-2018
Publisher: Chemical Engineering Department, Syiah Kuala University
Date: 17-08-2020
Abstract: The new composite material Al(III)-TiO2 has been synthesized and applied as a modifier of graphene paste electrode for the determination of fipronil pesticide by cyclic voltammetry. The methods were to synthesis of Aluminum-Titanium dioxide (AT), preparation of graphene paste electrode with mass varied Al(III)-TiO2 (GAT) (0.05 g, 0.1 g, 0.2 g), and fipronil electroanalytic respons. Addition of Al(III)-TiO2 to the graphene paste electrode shows redox properties which are well characterized by a fast electron transfer process. Based on the results of measurements in a solution containing fipronil, it is known that fipronil is oxidized at a potential value of 0.26 V. Furthermore, the fipronil oxidation process on the GAT surface is influenced by diffusion control, this is powered by R2 value 0.91 when plotted between peak oxidation currents (Ipa) vs. root scan rate. Other results show that measurement linearity is in the range 0.01 to 0.09 µg/L with a limit of detection (LOD) value of 0.0164 μg/L. Moreover, GAT shows good stability in the determination of fipronil with% RSD equal to 5%.
Publisher: Elsevier BV
Date: 09-2019
Publisher: Springer Science and Business Media LLC
Date: 25-03-2022
Publisher: MDPI AG
Date: 06-09-2022
Abstract: Platinum naturally crystalizes into a three-dimensional crystal due to its highly symmetrical fcc lattice, with a metallic bond which is non-directional and highly isotropic. This inherently means ultimately that 2D crystals of a few atoms thick growth are hardly available in this material. Here, we discovered that a combinative effect of formic acid reductant and hexamethylenetetramine surfactant during the reduction of their metal ions precursor can realize an ultimate thin 2D crystal growth in platinum. High-resolution transmission electron microscopy and filed-emission electron microscopy analysis have also discovered that the 2D crystal of Pt has 111 facets with a lateral dimension that can be up to more than 5 μm × 2 μm. The thickness of the 2D crystal of Pt is 1.55 nm. A mechanism for obtaining ultimate thin 2D crystal of Pt using the present approach is proposed.
Publisher: Elsevier BV
Date: 06-2017
Publisher: Oriental Scientific Publishing Company
Date: 28-12-2015
DOI: 10.13005/OJC/310462
Publisher: IOP Publishing
Date: 11-2017
Publisher: IOP Publishing
Date: 2021
DOI: 10.1088/1755-1315/622/1/012033
Abstract: This study is a follow-up of nickel slag waste used for building construction materials. Paving blocks were made using a mixture of cement and aggregates in a ratio of 1: 3 and 1: 5 which used a mixture of nickel slag waste and natural sand with aggregate gradation in zone III of the rather fine sand category based on SNI 03-2834-2000. Sand substitution with nickel slag waste has used a variation of the composition of the mixture of 0% (without slag), 25%, 75%, and 100% (without sand). The behaviour would be obtained the compressive strength value of paving blocks and average water absorption. Paving blocks compressive strength were tested at the age of 28 days, while the average value of water absorption was performed by immersing the paving block specimens for 24 hours. The physical strength and absorption value of paving block water refer to SNI 03-0691-1996. The results showed that the use of nickel slag waste in making paving blocks could increase the compressive strength of paving blocks, while water absorption in all compositions and variations of the paving blocks mixture was decreased in line with the increase of nickel slag composition.
Publisher: Elsevier BV
Date: 08-2019
Publisher: Elsevier BV
Date: 04-2015
Publisher: Springer Science and Business Media LLC
Date: 23-05-2020
Publisher: Asian Journal of Chemistry
Date: 2018
Publisher: Asian Journal of Chemistry
Date: 2018
Publisher: Journal of Applied Pharmaceutical Science
Date: 05-11-2020
Publisher: Springer Science and Business Media LLC
Date: 22-08-2019
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012038
Abstract: This study reports the processing and separation of gum rosin from pine gum (Pinusmerkusii). The research method was carried out with several stages, namely the process of tapping pine gum, the process of separation and purification. After the refining process, the gum rosin and turpentine oil are separated using a simple distillation technique. The results of gum rosin separation obtained from the distillation process were 86.67 with a soft point of 78.8°C, a vaporizing component of 0.976%, an acid number of 175.3125 and a saponification number of 178.81875. In addition to knowing the components of the gum rosin s les obtained, the identification of compounds was carried out using Fourier Transform Infrared Spectrophotometer (FTIR) and Gas Chromatography-Mass Spectrometry (GC-MS). The results of FTIR identification showed the presence of sp 2 C-H,-OH, sp 3 C-H, C=O,-CH 2 and - CH 3 groups, while GC-MS identification showed the presence components of Caryophyllene, Pimaric acid, Dehydroabietic acid, Abieticacid, and á-Pinene. The identification results indicate that the residue from the simple distillation is gum rosin.
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012039
Abstract: Preparation of Cu-doped TiO 2 nanoparticles (Cu/TiO 2 ) as antifungal Phytophthorapalmivorahas been carried out. In this study, we did a synthesis of Cu/TiO 2 nanoparticles by the sol-gel method and determine the performance of the modification of Cu/TiO 2 nanoparticles as antifungal agents P. palmivora . The stages of this research include synthesis of Cu/TiO 2 nanoparticles using the sol-gel method, characterization of Cu/TiO 2 nanoparticles using UV-Vis DRS and characterization of Cu/TiO 2 nanoparticles using SEM-EDX, and P. palmivora antifungal activity test. TiO 2 is known to be used as an antifungal agent and to increase photocatalyticactivity, TiO 2 is doped with Cu metal ions to be active in visible light. The results showed that Cu/TiO 2 has a band gap energy of 3.12 eV. Based on the results of SEM-EDX analysis of TiO 2 -Cu nanoparticles confirmed the presence of elements Cu (2.16%), Ti (28.74%) and O (69.10%) with morphological shapes such as irregular spheres. Cu/TiO 2 nanoparticles have a strong ability at concentrations of 0.05% and 2.5% in inhibiting the growth of the fungus P. palmivora . Percent inhibition respectively 60.41% and 75% and at concentrations % have activities that can kill P. palmivora fungus.
Publisher: Springer Science and Business Media LLC
Date: 31-05-2021
DOI: 10.1038/S41598-021-90891-3
Abstract: Research on the transformation of Oil Palm Empty Fruit Bunches (OPEFB) through pretreatment process using ionic liquid triethylammonium hydrogen sulphate (IL [TEA][HSO 4 ]) was completed. The stages of the transformation process carried out were the synthesis of IL with the one-spot method, optimization of IL composition and pretreatment temperature, and IL recovery. The success of the IL synthesis stage was analyzed by FTIR, H-NMR and TGA. Based on the results obtained, it showed that IL [TEA][HSO 4 ] was successfully synthesized. This was indicated by the presence of IR absorption at 1/λ = 2814.97 cm −1 , 1401.07 cm −1 , 1233.30 cm −1 and 847.92 cm −1 which were functional groups for NH, CH 3 , CN and SO 2 , respectively. These results were supported by H-NMR data at δ (ppm) = 1.217–1.236 (N–CH 2 –CH 3 ), 3.005–3.023 (–H), 3.427–3.445 (N–H + ) and 3.867 (N + H 3 ). The TGA results showed that the melting point and decomposition temperature of the IL were 49 °C and 274.3 °C, respectively. Based on pretreatment optimization, it showed that the best IL composition for cellulose production was 85 wt%. Meanwhile, temperature optimization showed that the best temperature was 120 °C. In these two optimum conditions, the cellulose content was obtained at 45.84 wt%. Testing of IL [TEA][HSO 4 ] recovery performance for reuse has shown promising results. During the pretreatment process, IL [TEA][HSO 4 ] recovery effectively increased the cellulose content of OPEFB to 29.13 wt% and decreased the lignin content to 32.57%. The success of the recovery process is indicated by the increasing density properties of IL [TEA][HSO 4 ]. This increase occurs when using a temperature of 80–100 °C. The overall conditions obtained from this work suggest that IL [TEA][HSO 4 ] was effective during the transformation process of OPEFB into cellulose. This shows the potential of IL [TEA][HSO 4 ] in the future in the renewable energy sector.
Publisher: IOP Publishing
Date: 02-2019
Publisher: Elsevier BV
Date: 04-2015
Publisher: Asian Agricultural and Biological Engineering Association
Date: 10-2019
Publisher: Springer Science and Business Media LLC
Date: 21-05-2022
Publisher: Elsevier BV
Date: 10-2019
Publisher: Elsevier BV
Date: 12-2023
Publisher: Japan Oil Chemists' Society
Date: 2021
DOI: 10.5650/JOS.ESS20282
Publisher: IOP Publishing
Date: 02-2020
DOI: 10.1088/1742-6596/1463/1/012011
Abstract: Research has been conducted to synthesize and characterization composite LAO-TiO 2 based on LAO mass variation and calcination temperature and its application as an adsorbent of lead metal (Pb). Characterization is done using X-Ray Diffraction (XRD) at an angle of 2θ: 5-60° of LAO mass variation for pillarization, which are 2, 3, and 5 with calcination temperature of 200, 250 and 300°C. The testing of the composite LAO-TiO 2 as lead (Pb) metal absorbent using Atomic Absorption Spectroscopy (AAS). The result shows the most significant basal spacing (d-spacing) is on mass variation 5 g (K5) after calcination with temperature 200 10.19 Å. Composite LAO-TiO 2 Application as lead (Pb) metal adsorbent shows the adsorption capacity (Q) obtained ranges from 4.4-4.9 mg/g.
Publisher: MDPI AG
Date: 25-10-2020
Abstract: Synthesis of Ni- and N-doped Titania Nanotube Arrays (Ni-N-TiNTAs) was conducted to produce photocatalysts for hydrogen production from a glycerol–water mixture. Ni-N-TiNTAs were synthesized in two steps, namely anodization and chemical reduction. Ti foil was anodized at 50 V for two h in an electrolyte solution containing 0.2% urea as a source of N atoms. Ni doping (at various content of 5%, 10%, 15%, and 20% wt) was performed by one-hour chemical reduction with sodium borohydride as a reducing agent. The photocatalyst was annealed at different temperatures, i.e., 500 °C, 550 °C, and 600 °C under 60 mL/min N2 gas for two h. On the basis of X-ray Diffraction (XRD) patterns, Ni-N-TiNTAs are mostly of anatase crystallite phase when annealed at 500 °C and 550 °C, while that of rutile was observable when calcination was done at 600 °C. The morphology of the photocatalysts was scrutinized by means of Field Emission Scanning Electron Microscopy (FESEM) imaging, which reveals nanotubular structures, with elemental composition measured by Energy Dispersive X-ray (EDX). The bandgap of the photocatalysts was analyzed using Ultraviolet Diffuse Reflectance Spectroscopy (UV DRS), which showed a lower value for the case of Ni-N-TiNTAs as compared to those of TiNTAs and N-TiNTAs. Photocatalytic tests showed that the highest amount of hydrogen produced (ca. 30973 μmol/m2) was obtained in the case of Ni-N-TiNTAs with a Ni content of 10wt%.
Publisher: Royal Society of Chemistry (RSC)
Date: 1998
DOI: 10.1039/A708203G
Publisher: Faculty of Pharmacy and Pharmaceutical Sciences, University of Karachi
Date: 07-2020
Publisher: IOP Publishing
Date: 05-2018
Publisher: Journal of Applied Pharmaceutical Science
Date: 05-02-2020
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012041
Abstract: FeTiO 3 doped TiO 2 /Ti eletrode synthesized through a sol-gel and dip-coating methods for Reactive Green 19 (RG-19) degradation under UV-Visible irradiation. The electrode was characterized by Scanning Electron Microscope (SEM), Linear Sweep Voltammetry (LSV), and Multi Pulse Amperometry (MPA). The electrodesurface show that a FeTiO 3 layer is quite thin and evenly distributed on the surface of the TiO 2 /Ti electrode. The photocurrent responses of TiO 2 /Ti and FeTiO 3 doped TiO 2 /Ti showed the TiO 2 /Ti electrode was active in UV light, while FeTiO 3 doped TiO 2 /Ti was active in the visible light. The optimum condition show that the TiO 2 /Ti dopedFeTiO 3 provided RG-19 degradation activity of 95%.
Publisher: Elsevier BV
Date: 12-2017
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012040
Abstract: The design of the Chemical Oxygen Demand (COD) flow system using TiO 2 /Ti and N-TiO 2 /Ti electrodes has been carried out. TiO 2 /Ti electrodes were synthesized from the anodizing process followed by the sol-gel method as nitrogen doping (N) to obtain N-TiO 2 /Ti electrodes. The test results obtained that TiO 2 /Ti electrodes are only active in UV light and N-TiO 2 /Ti electrodes can be active in visible light. Determination of the COD value of the flow system for glucose and potassium hydrogen phthalate at various concentrations respectively of 5, 10, 20, and 30 ppm was carried out using the Multi Pulse Amperommetry (MPA) technique. The results of the COD sensor measurement of the flow system on the potassium hydrogen phthalate and glucose obtained light currents increase in proportion to the increase in concentration, which is also significantly proportional to the increase in COD value. The highest COD values for glucose and potassium hydrogen phthalate were at concentrations of 30 ppm respectively of 29.73 and 31.34 mg/L O 2 using TiO 2 /Ti electrodes and for N-TiO 2 /Ti electrodes respectively 30.91 and 29.20 mg / L O 2 .
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012043
Abstract: Fabrication of FeTiO 3 -TiO 2 /Ti composite electrodes has been successfully carried out by the hydrothermal method and dip coating. The purpose of this study was to determine the effect of the addition of Ilmenite (FeTiO 3 ) on TiO 2 /Ti plates which will be applied to degrade Reactive Red 141 by photoelectrocatalytic. The characterization results using XRD showed the success of FeTiO 3 support on TiO 2 /Ti produced in the form of anatase crystals with peaks of 2θ = 39.88°, 52.71°, 62.71°, 64.51° and 67.54°. The SEM results show that the thin films are 10 μm, 5 μm and 2 μm while the EDX results show that the FeTiO 3 dopant on the TiO 2 / Ti plate is marked by marked peaks of Fe, Ti and O each with an elemental composition of 0.17%, 74.73%, and 25.10%. Characterization using FTIR showed the emergence of O-H, Ti-O, and Fe-O groups respectively with wave number absorption 3383 cm −1 , 1132 cm −1 , and 474 cm −1 . Characterization using LSV showed that the TiO 2 /Ti electrode was active in UV light, while the FeTiO 3 -TiO 2 /Ti electrode was active in visible light. The degradation test against Reactive Red 141 using TiO 2 /Ti electrodes under UV light showed maximum performance at a concentration of 0.5 ppm with a percent degradation of 89.21% while using FeTiO 3 -TiO 2 /Ti electrodes under visible light showed maximum performance at a concentration of 0.5 ppm with 96.65% degradation.
Publisher: The Korean Electrochemical Society - English Journal
Date: 31-12-2019
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012042
Abstract: Cu-TiO 2 doped Ti thin layer was prepared by anodizing and electrodeposition. Characterization electrode using Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX) and activity test using Linear Sweep Voltammetry (LSV) under UV and visible light to degrade methylene orange. The result of electrode surface characterization using EDX showed that the Cu peak at 0.992 keV indicated the precious metal Cu on the TiO 2 /Ti electrode. The activity test of Cu-TiO 2 /Ti electrode by Linear Sweep Voltammetry (LSV) showed the electrode activities on the visible light. The TiO 2 /Ti electrode has activities on the UV light. Degradation test Cu-TiO 2 /Ti electrode by photoelectrocatalyst against methylene orange showed the percentage of degradation produced was 92.88%.
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012045
Abstract: The past few decades Dye-Sensitized Solar Cells (DSSC) based on TiO 2 nanoparticle have attracted much attention from researchers because of their promising Physico-chemical properties and high photoconversion efficiency. In this research, TiO 2 nanoparticles mediated with hexamethylenetetramine surfactant were successfully synthesized by the hydrolysis method. The influence of hexamethylenetetramine surfactant precursor concentration on DSSC photovoltaic performance was investigated. The prepared s les are characterized by field emission scanning electron microscopy, X-ray diffraction, and UV–vis absorption spectroscopy. SEM analysis results show that the HMT surfactant has a big influence on the morphology, particle size, and crystal phase of TiO 2 particles. The surface morphology exhibited the nanorice grain particles in all s les. By spectrophotometry, it was shown that the films had a bandgap of about 2.9 eV. The film promoted by HMT 0.3 M from DSSC showed a power conversion efficiency of 1.7%.
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012044
Abstract: Decomposition of lignin compounds into monomers from oil palm empty fruit bunches (OPEFB)has been successfully carried out. The purpose of this study was to determine the use of ilmenite as a lignin decomposerof OPEFB and to analyze the compounds produced using GC-MS method. The stages of the study consisted of preparation of ilmenite, pretreatment process of OPEFB, characterization of lignin isolates using FTIR, analysis of lignin content by UV-Vis, and photodegradation of lignin by GC-MS. Ilmenitewas known to have a potential for decomposing the lignin compound through a photodegradation reaction, in the presence of ultraviolet light. The results of this study indicated that a time of five hours decomposition could have degraded lignin up to 50%. The longer the degradation time, the more lignin was degraded to produce materials in the form of phenolic compounds, furan compounds, benzene derivatives and carbon compound derivatives from lignin monomers. One of the benzene derivatives obtained was 3,4-di (methoxycarbonyl) benzoic acid (C 11 H 10 O 6 ).
Publisher: MDPI AG
Date: 02-03-2021
DOI: 10.3390/SU13052679
Abstract: Clean water is an unlimited and sustainable need that must be fulfilled every day and meet an appropriate standard in terms of quantity and quality. The research objective in this study was to analyze the quality of water in thirty freshwater springs and twenty four brackish springs in the karst area of Buton Tengah Regency to achieve sustainable water resource management. Data on the quality of freshwater springs and brackish water springs chemically and biologically have been analyzed in the biology laboratory of FMIPA Universitas Halu Oleo, then the results are compared with the standards for water quality contained in the regulations of the Minister of Health and Government Regulation of the Republic of Indonesia. The results showed that the freshwater springs in Talaga Raya District exceeded the water quality standards for hardness parameter, while the brackish springs in Mawasangka Tengah, Mawasangka Timur, Lakudo, and Mawasangka Districts has exceeded the water quality standards for parameters of total dissolved solids, hardness, and chloride. However, these parameters are relatively easy to overcome so that the use of freshwater springs can qualify as drinking water, while the use of brackish springs should be used to meet domestic non-drinking water needs.
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012047
Abstract: Preparation of TiO 2 /Ti and Mn-TiO 2 /Ti electrodes was successfully carried out. The purpose of this study was to effect the addition of manganese (Mn) to TiO 2 which will be used to degrade congo red organic compounds by photocatalysis. TiO 2 is made through an anodic oxidation process. Mn coating is done by doping using the electrodeposition method. The results of the characterization using XRD showed that the TiO 2 /Ti electrodes were produced in the form of anatase crystals. SEM results show that nanotubes formed on the surface of the thin layer of TiO 2 /Ti. EDX results show the presence of manganese metal on the surface of TiO 2 /Ti of 6.58%. The characterization results using LSV showed that the TiO 2 /Ti electrode was active in UV light at a concentration of 1 ppm with 51.23% degradation and the Mn-TiO 2 /Ti electrode was active at Visible light at a concentration of 1 ppm with 75.48% degradation.
Publisher: IOP Publishing
Date: 05-2021
DOI: 10.1088/1742-6596/1899/1/012046
Abstract: Studies on the synthesis of TiO 2 /Ti doped Se electrode to degrade reactive orange 84 (RO 84) compounds under UV-Visible irradiation have been successfully carried out. The research objective is to obtain the Se-TiO 2 /Ti electrodes and test performance in degrading RO 84 under irradiation of UV-Visible light by photoelectrochatalytic. Se-TiO 2 /Ti electrode were prepared by anodizing and dip coating methods. XRD analysis of TiO 2 /Ti electrode showed the formation of anatase crystals. The surface morphology of the electrode showed the nanotube structure while the composition of the elements in the electrodes was determined by EDX and the presence of selenium was detected at 0.80%. The characteristics of using Linear Sweep Voltammetry (LSV) show that TiO 2 /Ti electrodes are active in UV light, while Se-TiO 2 /Ti electrodes are active in visible light. Electrode activity test in degrading RO 84 showed that the Se-TiO 2 /Ti photoelectrocatalis performance with variations in UV and irradiation of visible light was good in integrating RO 84 with a degradation rate of 98%.
Publisher: American Chemical Society (ACS)
Date: 20-09-2018
Publisher: Wiley
Date: 06-2020
Publisher: IOP Publishing
Date: 2021
DOI: 10.1088/1742-6596/1763/1/012068
Abstract: Exploration of lichen natural compounds has attracted a lot of attention from researchers as potential medicinal raw materials because chemical compounds contained in lichen have many properties. The potential for developing secondary metabolite compounds of lichen has become a trend for various benefits, for ex le, in cosmetics, agriculture, health, and food. Lichen Teloschistes flavicans was a concern to study because there were not many reports of secondary metabolites that have antimicrobial activity. The research objective was to examine antimicrobial activity using 3-[1’-(2”,3”-dihydroxy-phenyl)-propyl]-7hydroxy-chroman-4-one compound from lichen Teloschistes flavicans . The antimicrobial activity test was a well diffusion method. Bioactivity was determined by calculating the clear zone formed around the well. Antimicrobial activity testing indicated the inhibition of bacterial growth at a concentration of 500 ppm and 1000 ppm with the respective inhibition zones namely E. coli (10-11 mm), S. Typhi (2-5 mm), K. pneumoniae (11-13 mm), and S. aureus (10-13 mm). Also, B. cereus bacteria and C. albicans fungi were only inhibited at a concentration of 1000 ppm with an inhibition zone of 6 mm each. This research provides scientific knowledge about the potential development of lichen T. Flavicans as an antimicrobial.
Publisher: IOP Publishing
Date: 2021
DOI: 10.1088/1742-6596/1763/1/012069
Abstract: The TiO 2 /Ti and S-TiO 2 /Ti electrodes are effectively prepared using the anodizing process. The objective of this analysis is to determine the characteristics of the S-TiO 2 /Ti electrode and its efficiency as a photoelectrocatalytic sensor device. The composite electrode of S-TiO 2 /Ti was prepared using the Ti plate anodizing method in glycerol and NH 4 F 0.27 M with a bias potential of 25 V for 4 h followed by calcination at 500 °C for 90 minutes. Doping S to the TiO 2 /Ti electrode was carried out in sol-gel containing sulfur by the dip-coating process and then calcined for 10 minutes at 150 °C. The obtained TiO 2 /Ti and S-TiO 2 /Ti electrodes are characterized by UV-Vis DRS, XRD, SEM-EDX, and FTIR techniques. TiO 2 /Ti was shown to be active under UV light, while S-TiO 2 /Ti was active under visible light. We also observed that the best composition of the S-TiO 2 /Ti electrode was 1 M with a current value of 5.71x10 −5 A in the visible area. The S-doped TiO 2 /Ti electrode photoelectrocatalytic activity was stronger than the undoped electrodes under visible light area irradiation.
Publisher: Springer Science and Business Media LLC
Date: 04-2021
Publisher: IOP Publishing
Date: 05-2018
Publisher: IOP Publishing
Date: 05-2018
Publisher: Asian Journal of Chemistry
Date: 2017
Publisher: Oriental Scientific Publishing Company
Date: 25-12-2017
DOI: 10.13005/OJC/330651
Publisher: IOP Publishing
Date: 05-2018
Publisher: Oriental Scientific Publishing Company
Date: 22-12-2015
DOI: 10.13005/BBRA/1865
Publisher: IOP Publishing
Date: 06-2019
DOI: 10.1088/1742-6596/1242/1/012017
Abstract: Lignin from oil palm empty fruit bunches (OPEFB) has been degraded using ilmenite mineral (FeO.TiO 2 ). The FeO.TiO 2 was examined for antibacterial activity against E. coli , S. aureus , S. typhi , and X. oryzae . It was extracted from iron sands by a magnetic separator and pre-oxidized at 800ºC for 5 hours. Meanwhile, OPEFB was prepared with a pretreatment process using 10% NaOH solution to damage ester bonds between lignin, hemicellulose, and cellulose. Furthermore, the lignin was degraded by using FeO.TiO 2 catalyst with the study of catalyst mass, degradation time, and lignin concentration variation. Based on XRF and XRD data indicated that the pre-oxidation result of iron sand was contained Fe 2 O 3 (hematite) and FeO.TiO 2 minerals with the highest dominant of Fe content in the s le. The result of lignin photodegradation using FeO.TiO 2 catalyst showed that the lignin-derived compound obtained was Coniveryl Alcohol (C 10 H 12 O 3 ). Antibacterial activity test against 4 bacterial s les i.e E. coli , S. aureus , S. typhi , and X. oryzae showed that each test has good activity in inhibiting bacteria with a range of inhibiting diameter zone between ±20 nm. Based on this study provides that lignin-derived compounds from OPEFB can be used as a natural antibacterial.
Publisher: IOP Publishing
Date: 06-2019
Publisher: IOP Publishing
Date: 06-2019
DOI: 10.1088/1742-6596/1242/1/012016
Abstract: The objective of this research to synthesize the Selenium (Se) doped TiO 2 /Ti electrode as a novel chalcogenide material by anodizing and dip-coating method. The electrode was applied for Rhodamine B (RhB) degradation test in high-photoelectrochatalytic (PEC) performance. It is found out that the morphology and element containing on Se-TiO 2 /Ti electrode has honeycomb structure with the element composition of Ti (51.09%), O (36.91%), and Se (12.00%), respectively. In addition, the PEC response test using Linear Sweep Voltammetry (LSV) showed that the optical properties of Se-TiO 2 /Ti electrode was active under visible light, meanwhile the TiO 2 /Ti was active under ultraviolet (UV) light. The PEC test using Multi Pulse Amperometry (MPA) technique was exhibited that the 5 ppm RhB corresponded to the degradation of 73.27%.
Publisher: AIP Publishing
Date: 2020
DOI: 10.1063/5.0001501
Publisher: IOP Publishing
Date: 2021
DOI: 10.1088/1742-6596/1763/1/012070
Abstract: In this work, TiO 2 -Ag composites have been synthesized through the Ultrasonic Batch Cleaning technique and applied as an antifungal candidate against Phytophthora palmivora . P . palmivora is a pod rot fungus on cacao plants. Physically, the successful synthesis of TiO 2 -Ag has been characterized by a change in the color of the precipitate from white to grey. This success was confirmed by Scanning Electron Microscopy (SEM) analysis, where the presence of Ag + ions made the TiO 2 surface more regular. The Ag + ion was evenly distributed on the TiO 2 surface and covers the large TiO 2 particles. The results of EDX analysis have shown that the % composition of TiO 2 -Ag was 93.22%, each consisting of Ti of 50.37%, O of 37.57%, and Ag of 5.25%. Based on the antifungal activity test, TiO 2 -Ag has good antifungal activity against P. palmivora . The minimum inhibitory level occurred at a concentration of 2.50%, while the minimum lethal rate occurred at a concentration of 4.88%.
Publisher: Elsevier BV
Date: 03-2019
Publisher: Elsevier BV
Date: 07-2020
Publisher: Author(s)
Date: 2017
DOI: 10.1063/1.5011868
Publisher: Research Square Platform LLC
Date: 03-03-2022
DOI: 10.21203/RS.3.RS-1384241/V1
Abstract: Photoelectrochemical oxidation processes offer a highly sensitive method to detect organic pollutants from wastewaters. Photoactive semiconducting material is the key factor in this process that accelerates the oxidation of the organic pollutant agent for sensitive detection. Chalcogenide doped TiO 2 system has so far come up as a potential photocatalyst system for photoelectrochemical detection of organic compounds. Here, we report a highly sensitive detection of chemical oxygen demand of organic compound pollutant using sulfurized-TiO 2 (S-TiO 2 /Ti) nanotube arrays (NTA) photoelectrocatalyst. S-TiO 2 /Ti NTA that is prepared via consecutive anodization of Ti sheet and TiO 2 sulfurization process exhibited a high sensitivity to COD value of organic compounds pollutant, such asRed HE-3B (Reactive Red 120), Red HE-7B (Reactive Red 141), and Blue HE-RD (Reactive Blue 160). Our results indicated that the COD value is linearly correlated with the concentration of the organic compounds and is close to the COD theoretical value, inferring the high accuracy of the detection. This explains that the new S-TiO 2 /Ti NTA photoelectrocatalyst effectively enhances the electron transfer dynamic during the electrochemical measurement of an organic pollutant that is reflected by an impressive proportionality of electrochemical current to the concentration of the pollutant s le. The S-TiO 2 /Ti NTA promises a highly efficient pollutant detection in the environment.
Publisher: Institute of Research and Community Services Diponegoro University (LPPM UNDIP)
Date: 07-05-2020
DOI: 10.14710/JKSA.23.5.167-176
Abstract: The development of polypyrrole as a potential mediator membrane candidate for sodium dodecyl sulfate (SDS) sensor electrode has been investigated. The polypyrrole membrane was synthesized electrochemically from the pyrrole and coated at the surface of a 1.0 mm diameter of the gold-wire electrode. Electropolymerization of pyrrole and coating of the polypyrrole produced was performed by cyclic voltammetry technique in the electrochemical cell containing supporting electrolyte of 0.01 M NaClO4 with an optimum potential range of -0.9 V–1.0 V, the scanning rate of 100 mV/s, an electric current of 2 mA, and running of potential scanning of 10 cycles. By using the similar optimal parameters of cyclic voltammetry, electropolymerization of 0.01 M pyrrole solution containing 0.001 M SDS also produces a polypyrrole membrane coated at the gold-wire electrode surface. These coated electrodes have the potential response-ability toward DS- anions in the concentration range of 10-7 M–10-5 M with a limit of detection of 10-7 M and sensitivity of electrode of 9.9 mV/decade. This finding shows that the SDS solution’s role is as supporting electrolyte and also as a source of DS- dopant during the pyrrole electropolymerization processes. Dopants are trapped in the polymer membrane during the electrochemical formation of polypyrrole and role as ionophores for DS- anion in the analyte solution. A potential response to the electrode phenomena is excellent basic scientific information for further synthesis of conducting polymer and development of conducting polymer-coated wire electrode model, especially in the construction of ion-selective electrode (ISE) for the determination of anionic surfactants with those models.
Publisher: Springer Science and Business Media LLC
Date: 30-05-2023
Publisher: AMG Transcend Association
Date: 03-2021
DOI: 10.33263/BRIAC116.1387813884
Abstract: In the last decade, lichen has become a research interest related to exploring secondary metabolites compounds. Lichen is a unique organism and contains specific chemical compounds rarely found in other natural sources one species is the lichen Teloschistes flavicans. The objective study explores the toxicity effects and antioxidants activity properties from lichen Teloschistes flavicans isolate. The isolation of secondary metabolites was carried out by extraction, separation, and purification by means of gravity column chromatography, thin-layer chromatography, and purity tests. Toxicity activity test used the Mayer method by looking at the LC50 value, while the antioxidant activity test used the DPPH method by looking at the IC50 value. The results of the isolation obtained a needle-shaped crystal with the name of the compound is 3-[1'-(2",3"-dihydroxy-phenyl)-propyl]-7-hydroxy-chroman-4-one and the molecular formula C18H18O5. The toxicity test showed that extract and isolate compounds have LC50 values of 9.38 and 162.18 µg/mL, indicating that the isolated compound was toxic. The antioxidant test showed that the extract and isolated compounds have antioxidant activity with IC50 values of 54.05 and 127.38. The results of these studies provide scientific development of natural compounds that have the potential to act as antioxidants for diseases in the human body.
Publisher: Springer Science and Business Media LLC
Date: 25-07-2020
Publisher: IOP Publishing
Date: 2021
DOI: 10.1088/1742-6596/1763/1/012067
Abstract: Electrochemical studies in detecting persistent organic pollutants (POPs) have attracted a lot of interest from researchers, especially the carbon paste electrode (CPE). The research objectives were to determine the electrochemical characteristics of TiO 2 /Ag-Li on the CPE in the system Fe 2+ /Fe 3+ and determine the fipronil in solution. TiO 2 /Ag-Li preparation was carried out by using the sol-gel method. Electrochemical performance of CPE was applied by cyclic voltammetry. The system developed was a reversible redox reaction and have peaks Ipa 110 µA and Ipc 105 µA. We also found that the composition of the best modifier addition to CPE was using TiO 2 /Ag-Li with a mass of 0.005 g. The optimum scan rate for the measurement of the fipronil test solution was obtained at 0.2 V/s with an Ipa value of 15 µA and an Epa value of 0.40 V. Based on the plot between the root scan rate and the oxidation current of the solution containing fipronil, the obtained R 2 value was 0.9806. This research provides the development of modifier CPE material with the well electrochemically performance and considered as a very effective monitored system for the environment contaminated by POPs waste.
Publisher: Soil Science Society of Poland
Date: 09-09-2020
Publisher: Oriental Scientific Publishing Company
Date: 23-10-2016
DOI: 10.13005/OJC/320545
Publisher: IOP Publishing
Date: 11-2017
Publisher: IOP Publishing
Date: 11-2017
Publisher: Institute of Research and Community Services Diponegoro University (LPPM UNDIP)
Date: 05-2020
DOI: 10.14710/JKSA.23.5.147-151
Abstract: This study was aimed to examine the production of microcrystalline cellulose (MCC) from tapioca solid waste (TSW), using HCl hydrolysis with various concentrations, i.e., 2 N, 2.5 N, 3 N, and 3.5 N. MCC was produced by delignifying the TSW with NaOH 20%, and bleaching with NaOCl 3.5% to produce α-cellulose, and subsequently hydrolyzing α-cellulose with three different HCl concentrations to produce MCC. The physicochemical properties of MCC were then analyzed, including Scanning Electron Micrograph (SEM), X-ray diffraction (XRD), and FTIR spectra. The results showed that hydrolysis with 2.0 N HCl resulted in a higher yield of 61.28%, α-cellulose content of 56.33%, moisture 6.25%, pH of 6.54 ash 0.23%, and water solubility 0.34%. SEM analysis showed the morphology and size of the MCC produced were like those of a commercial MCC (Avicel PH101), while the XRD analysis showed the higher concentration of HCl gave rise to an increased crystalline index. FT-IR spectrum analysis indicated that TSW, MCC produced, and commercial MCC had similar functional groups.
Publisher: IOP Publishing
Date: 11-2017
No related grants have been discovered for Muhammad Nurdin.