bluuebunny/crossref_metadata_2025_split huggingface dataset:
Potency of Modified Cassava Flour as Binder and Thickener in Formulation of Instant Infant Porridge using Fortificant of Natural Folic Acid
Authors: Susilowati Agustine , Maryati Yati , Aspiyanto  
Published: July 2020

Abstract
A dry mixing process in preparation instant and pour infant porridges fortified by natural folic acid of A and B, and added by modified cassava (mocav) flour as thickener and binder had been conducted. Fortificant of natural folic acid of A and B are a mixture of soy bean tempeh, nixtamalized yellow corn and fermented broccoli, and a mixture of mung bean tempeh, nixtamalized yellow corn, and fermented broccoli. This experiment aims to optimize by adding mocav flour and the best type of natural folic acid in preparing instant and pour infant porridges for complementary breastfeeding (CBF) and its characteristic on the whole composition, particularly folic acid, characteristic of folic acid monomer, volatile compounds, particle size, and particle size distribution on instant and pour infant porridges. The experiment were done on mocav flour with concentrations of 0, 6, 12, 18, 24, and 30% (w/w of base formula of infant porridge) with fortificant of natural folic acid of A and B, and pouring to produce instant and pour infant porridges A and B. The result of experiment showed that based on folic acid, process optimization was achieved on fortificant A at mocav concentration 18% (w/w, based formula of porridge) and increase folic acid 532.26% (5.30-folds), dissolved protein 226.62% (2.27-folds), total sugars 120.44% (1.20-fold), however drop total solids 4.61% and reducing sugars 14.94% in instant infant porridge compared to each components concentration in base formula of infant porridge. In this condition, volatile compounds of instant infant porridge and pour infant porridge dominated by acetic acid and its derivatives (44.21%), and furan and its derivatives (29.812%).
Computational study of Cu2+, Fe2+, Fe3+, Mn2+ and Mn3+ binding sites identification on HSA 4K2C
Authors: Wibowo Syahputra , Sumitro Sutiman B , Widyarti Sri 
Published: July 2020

Abstract
This research aims to computationally characterize HSA 4K2C protein and describe as well as its ability to bind transition metal ions. Data mining is performed to obtain HSA 4K2C from PDB and transition metal ions such as Cu2+ (ID: 27099), Fe2+ (ID: 27284), Mn2+ (ID: 27854), Mn3+ (ID: 105130) and Fe3+ (ID: 29936) from PubChem. The analysis consists of ProtParam, Motif Search, CFSSP, DLP-SVM, and docking. Docking used PyRx Autodock Vina. Analysis of receptor-ligand interactions used DS 2016. The results of the ProtParam analysis provide some information on HAS 4K2C, which is it has 585 amino acids with an isoelectric point (pI) of 5.67, an index of protein instability of 38.85, then total amino acids (aa) residues of negatively charged (Asp + Glu) are 98 while the positively charged ones (Arg + Lys) are 83. Motive Search shows that there are three HSA motifs namely motif 1 (aa. 551-575), motif 2 (aa. 353-377), and motif 3 (aa. 61-185). CFSP shows α -helix structure is the dominant structure compared to β-sheet, turn and coil in 4K2C. DLP-SVM shows two domain linkers where DL-1 (aa. 410-451) and DL-2 (aa. 96-122). Docking shows the ability of HSA 4K2C in binding metal ions such as Cu2+, Fe2+, Mn2+, Mn3+ and Fe3+.
Purification of Keratinase from Bacillus sp. MD24 using Ammonium Sulfate Fractionation
Authors: Zuhriyah U F , Susanti E , Suharti  
Published: July 2020

Abstract
A keratin degrading bacterium, Bacillus sp MD24, was isolated from soil. The crude keratinase produced by the bacterium has been reported to dehair goat skin. However, the dehairing process took 72 hours. In order to shorten the dehairing time it is necessary to increase the keratinase concentration. This could be done by optimizing keratinase production either finding the best fermentation media or optimizing fermentation condition. Another way to increase the concentration could be done by partially purifying the enzyme. Keratinase from Bacillus sp MD24 had been produced under submerged fermentation, however, it produced a relatively low amount of enzyme. Although an effort to increase enzyme production had been reported by solid state fermentation, the enzyme concentration was not enough for industrial purposes. This work aimed to increase enzyme concentration by partial purification through enzyme precipitation using ammonium sulphate. The research was conducted in three stages: (1) regeneration the bacterium, (2) production of keratinase, and (3) purification of keratinase with ammonium sulfate fractionation. Keratinase activity was measured by Anson method and protein concentration was measured by Lowry method. Enzyme purity was clarified using a combination of specific activity, purity level, and SDS-PAGE analysis. Based on the analysis result, ammonium sulphate did not act as a good precipitation agent for the keratinase. Two major bands were suggested as keratinase with an estimated molecular weight of 25 and 66 kDa as monomer and dimer form, respectively.
Synthesis of 5-(4-bromobutyl)-2,3-dimethyl-1,4-benzoquinone and the Solubility Test in n-Octanol/Water Partition System
Authors: Zuhroh Nadiyah , Ulfa Siti Mariyah 
Published: July 2020

Abstract
The modification structure of 1,4-benzoquinone is fascinating in the frame of drug design. The solubility properties of a new drug are important, especially for oral drug administration. The 2-isopropyl-5-methyl-1,4-benzoquinone (known as thymoquinone) which is the major constituent in Nigella sativa seed extract is known as an active compound with poor lipophilicity. Here, we reported the synthesis of 5-(4-bromobutyl)-2,3-dimethyl-1,4-benzoquinone which analog with thymoquinone having higher lipophilicity. The synthesis proposed by oxidation reaction of 2,3-dimethyl-1,4-hydroquinone (1) with H2SO4 followed by bromoalkylation reaction using bromopentanoic acid in the presence of AgNO3 and (NH4)2S2O8. The oxidation product 2,3-dimethyl-1,4-benzoquinone (2) and alkylated-quinone 5-(4-bromobutyl)-2,3-dimethyl-1,4-benzoquinone (3) were obtained in 52.64% and 5.85%, respectively. The FTIR analysis of 3 showed the additional C-Br stretching at 562 cm−1. The solubility test in n-octanol/water system using HPLC gave the log P value of 5-(4-bromobutyl)-2,3-dimethyl-1,4-benzoquinone (3) is 2.99, higher than thymoquinone. By this result, it is suggested that the modification of 1,4-benzoquinone by bromo alkylating agent increased the solubility of the compound.
Electrochemical Behavior of Nickel Laterite Ores Dissolution in Sulphuric Acid Solutions
Authors: Abidin Faizinal , Gunawan Wibowo Abdul Hatta , Ambari Arya An , Harjanto Sri 
Published: July 2020

Abstract
Hydrometallurgical process of laterite nickel ore is carried out by leaching techniques at high temperatures. At atmospheric temperatures, the acquisition of nickel is low. Therefore, this study aims to characterize the electrochemical laterite nickel ore using a solution of sulfuric acid and hydrochloric acid at atmospheric temperature. Sulfuric and chloride acid solutions were used with solution concentrations of 1 M, 2 M, 4 M and 6 M. The study was carried out by sample and solution preparation, characterization by SEM-EDAX and Petrography method, and electrochemical characterization using the OCP, EIS method and LSV. The characterization results showed that the highest dissolution rate in both solutions was obtained at a concentration of 6 M solution. Increased concentrations of sulfuric acid reduced the value of OCP testing, while an increase in the concentration of hydrochloric acid increased the value of OCP. The EIS test results showed that the lowest R2 or Rct value in sulfuric acid solution was obtained at 2M concentration of 269.59 Ω while in hydrochloric acid solution it was obtained at a concentration of 6M of 523.07 Ω. The results of the second LP acid solution showed the formation of a passive layer at each concentration. The highest dissolution rate occurred at a concentration of 6M in each solution where the corrosion rate of sulfuric acid was 1.00 mm / year, while in hydrochloric acid it was 9.55 mm / year. Increasing the concentration of the two solutions led to the breakdown of the passive layer on the surface which can be seen from the Nyquist curve, the value of R2 is lower, the value of Q1 is higher and the value of N is lower, but in the sulfuric acid solution the formation of passive layers returns to increasing concentration starting from 4M. The three electrochemical tests show an increase in concentration to the optimum concentration increasing the dissolution rate and breaking the passive layer on the surface.
The Effect of Aging and Crystallization Time on the Synthesis and Characteristics of Zeolite-Y from Malang-Quartzite Silica
Authors: Arni Sukrawati , Sumari Sumari , Santoso Aman , Tamara Tasya 
Published: July 2020

Abstract
The purpose of this study is to determine the effect of aging and crystallization time on the synthesis and characteristics of zeolite-Y. The raw material of silica used was obtained from the silica extraction of Malang quartzite by leaching and sol-gel methods. The extracted silica was analyzed using XRF and XRD. Synthesis of zeolite-Y was carried out using hydrothermal method by mixing NaOH, Al(OH)3, SiO2, and H2O according to the molar ratio of the elements in zeolite-Y. The aging process was carried out with time variations of 12, 24, 48 hours and the crystallization process were carried out with time variations of 6, 9, 12 hours at a 150 °C. The synthesized zeolite-Y was analyzed using XRF, XRD, FTIR, and SEM. The results showed that quartzite silica could be extracted by leaching and sol-gel methods with a yield of 99.1 wt%. The optimum condition of synthesis zeolite-Y was obtained at the aging time of 12 hours and the crystallization time of 12 hours.
The Structural and Optical Band Gap Energy Evaluation of TiO2-Fe2O3 Composite
Authors: Iqbal Rendy Muhamad , Pramoda Wardani Dyah Ayu , Hakim Luqman , Damsyik Akhmad , Safitri Riaa , Fansuri Hamzah 
Published: July 2020

Abstract
Solar cells, one of which is Dye Sensitizer Solar Cell (DSSC), are promising alternative energy in the 2000s. Compared to many other energy sources, solar cell does not emit waste (clean energy). An important component that generates electricity in DSSC is photoanode. TiO2, the most widely used materials as photoanodes in the current era, is widely used photoanode although the energy gap of the TiO2 band is quite large (3.43 eV). This study aims to reduce the energy gap of TiO2 band by forming composites with Fe2O3. Various compositions of TiO2 and Fe2O3 fine powders mixtures were dispersed in methanol and stirred until homogeneous in order to synthesize the photoanode. The methanol was then evaporated to obtain a dried mixture of solids, followed by calcination to form composites. The resulted composites were characterized by XRD and Diffuse Reflectance UV-Vis Spectrophotometer. XRD analysis results showed that the composites are composed of TiO2 and Fe2O3 mixtures. Diffuse Reflectance UV-Vis analysis results showed that there was a change in bandgap energy due to the mixing of TiO2 with Fe2O3. The lowest band gap energy is 2.67 eV at 1: 4 ratios. The smallest and largest refractive index values calculated by the Ravindra relation are 2.0725 and 2.4286, respectively. The refractive index value is the reversely proportional of the band gap energy value, the greater the band gap energy, the smaller the refractive index value.
Effect of sonication frequency in synthesis of silica aerogel-activated carbon nanocomposite
Authors: Muthomimah Siti , Rahayu Widi , Nazriati  , Aliyatulmuna Adilah 
Published: July 2020

Abstract
The silica adsorption capacity can be improved by composing it with activated carbon. The study aims to know the effect of sonication frequency in the nanocomposite silica aerogel-activated carbon synthesis using sol-gel method with TMCS (trimethylchlorosilane) and HMDS (hexamethyldisilazane) as modifying agents. Synthesized nanocomposites were further characterized by means of functional groups analysis using FTIR (Fourier Transform Infrared Spectrophotometry) method, morphological analysis using SEM (Scanning Electron Microscopy) method, and surface area analysis using BET (Brunauer-Emmet-Teller) method. The results of functional group analysis using FTIR shows that nanocomposite has a group of Si - OH, Si - O - Si, Si – C, C - H, C = O, C – O, the peaks around of 3300 cm−1, 1051 cm−1 - 1180 cm−1, 1253 cm−1, 2960 cm−1, 1649 cm−1, 1417 cm−1; morphological analysis using SEM indicates that nanocomposite synthesis with 42 kHz frequency sonication has a smaller particle size than 35 kHz frequency, where are the surface area analysis using BET method obtained 674.897 m! / g at frequency of 42 kHz and 486.909 m2 / g synthesis at frequency of 35 kHz.
Optical Emission Spectroscopy Study of the Electron Temperature and Electron Density Dependence on the Pressure Chamber for the Carbon Deposition Produced by Argon Plasma Sputtering
Authors: Pambudi D R S , Hanif M A , Santjojo D J D H , Padaga M C , Masruroh  
Published: July 2020

Abstract
An investigation of the Optical Emission Spectroscopy (OES) to study the effect of the pressure chamber to the chemical species, electron temperature (Te) and electron density (Ne) was performed on RF 2 MHz plasma sputtering for carbon deposition. A carbon target and argon (Ar) gas were used to deposit carbon films. The carbon deposition was carried out at pressure chamber of 10, 15 and 20 Pa, and the RF voltage, flow rate and substrate temperature were kept at 120 volts, 60 ml/min, and 200°C, respectively. The emission spectrum of Ar plasma was monitored by OES in order to analyze the chemical species present in the plasma during the deposition process. The atomic spectroscopy data center (NIST) database was used to determine the species in the plasma and to calculate the Te and Ne. The OES emission shows the peak intensity which indicates the Ar I (Ar*) and Ar II (Ar+ ion). The electron temperature was calculated using the Boltzmann Plot while the electron density was calculated using Stark Broadening. The results show that both Te and Ne decreased on the increasing of the pressure chamber. The emission line measurements with Boltzmann Plot resulted in the electron temperature dependence of pressure is approximately 0.487±0.005, 0.481±0.006, and 0.474±0.011 eV, respectively. Moreover, the calculation of electron density resulted in approximately (5.495 ± 0.407) × 1018, (4.825 ± 0.384) × 1018, and (4.515 ± 1.037) × 1018 cm−3.
The Effect of SrO Impregnation on The Characteristics of Cobalt Ferrite (CoFe2O4) Nanoparticles Synthesized by Coprecipitation
Authors: Primadi Thutug Rahardiant , Santoso Aman , Fajaroh Fauziatul 
Published: July 2020

Abstract
Cobalt Ferrite (CoFe2O4) nanoparticles are magnetic materials that have greater hardness than Fe3O4. CoFe2O4 is widely applied in many fields, including as a heterogeneous catalyst in various chemical reactions such as photocatalysis, phenol degradation, and transesterification reactions. This is supported by the thermal and chemical stability possessed by CoFe2O4. Coating or impregnation of non-magnetic material on the surface of the ferrite, on one side will reduce its magnetism and possibly its surface area. But on the other hand, the positive impact of coating or impregnation is the increase in particle monodispersity. Weakening the magnetism of the particles will reduce the interaction of attraction between particles, so that the particles are getting more monodisperse. This will optimize its potential as a heterogeneous catalyst. In this research impregnation of strontium oxide (SrO) would be carried out on the surface of CoFe2O4. After that, the characters were compared with CoFe2O4 before being impregnated. The CoFe2O4 synthesis was carried out through the coprecipitation method, followed by wet impregnation with SrO. The results showed that the impregnation of SrO on CoFe2O4 increased the zeta potential of the particles which indicated the stability of the particles in the dispersion.
Effect of Sonication Time on Characteristics of Synthesized Silica Aerogel Activated Carbon Nanocomposite Based on Bagasse Ash
Authors: Rahayu Widi , Muthomimah Siti , Sumari Sumari , Nazriati Nazriati 
Published: July 2020

Abstract
The purpose of this research was to identify the effect of sonication time on the characteristics of silica aerogel activated carbon (SA-AC) nanocomposite produced based on bagasse ash. SA-AC nanocomposites was synthesized by sol-gel method at ambient pressure. The silicic acid solution was mixed with activated carbon and the surface modifying agent (TMCS and HDMS). The mixture was then put in an ultrasonic bath at the varying sonication time of 5, 10, 15, and 20 seconds on frequency of 42 kHz. SA-AC nanocomposites were characterized by using FTIR, SEM, and BET. The results showed that SA-AC is formed, indicated by the wave number FTIR spectra of Si-O-Si (1076.28 cm−1), Si-C (1253.73 cm−1), C-H (2960.73 cm−1), C-O (1087.85 cm−1), C=C (2113.98 cm−1), and C=O (1942.32 cm−1). SA-AC nanocomposites synthesized by sonication assistence has a smaller agglomerate than that of without sonication. The largest surface area of SA-AC nanocomposite of 677.719 m2/g and the biggest pore volume of 0.6338 m3/g is obtained when the nanocomposite is synthesized at sonication time of 10 seconds
Inexpensive solar cell using TiO2/coffee composite as photon absorbing material
Authors: Rahman D Y , Utami F D , Margaretta D O , Amalia N , Sulistyowati R , Abdullah M 
Published: July 2020

Abstract
Solar cell using TiO2/coffee composite as photon absorbing material has been successfully fabricated. A suspension of TiO2/coffee was dropped on Fluorine Tin Oxide substrate which was previously heated on a hotplate with temperature of 100 °C. The fraction of coffee was varied from 10, 20, 30, 40, and 50 %, compared to the mass of TiO2. PVA-LiOH electrolyte polymer was functionalized as the hole transport medium. The highest efficiency of 0.76 % was achieved with 40% of coffee fraction. The solar cell is promising to be developed in the future due to the easy method and cheap materials used.
Preparation of Silver-Incorporated Rhynchospora corymbosa (L.) Cellulose via in-situ Green Reduction and Its Antibacterial Study
Authors: Rosdiana Fitri , Falahudin Aswin , Wibowo Risky Hadi , Yudha S. Salprima , Gustian Irfan 
Published: July 2020

Abstract
Silver incorporated R. corymbosa (L.) cellulose was obtained through the direct attachment (insertion) of silver ions to natural cellulose, followed by the green reduction of ions to metallic silver, using aqueous extract of fresh R. corymbosa (L.). In addition, Fourier transform infra-red (FTIR) analysis of the isolated cellulose showed some peaks at 3330 cm−1, 2890 cm−1, 1320 cm−1, 1030 cm−1, 895 cm−1 corresponding to OH stretching, methylene (-CH2-) stretching, OH bonding, C-O bonding, and 1,4 β-glycoside, respectively. The silver incorporated R. corymbosa (L.) cellulose was prepared by impregnating silver ions obtained from silver nitrate solution, followed by ion reduction to the metallic silver in-situ. Furthermore, another interesting outcome of this study is seen in the products’ ability to show inhibition zones in the growth medium of Escherichia coli.
Impedance Spectrum of QCM Sensor Coated With 18-Crown-6-Ether Solved in THF, Chloroform and Toluene
Authors: Setiana Mira , Zafirah Tyas N. , Masruroh  , Istiroyah  , Sakti Setyawan P. 
Published: July 2020

Abstract
Crown ether is a form of ethylene oxide cyclo-oligomer. Crown ether has a strong ability to form a complex with cations. The crown ether has been used as part of the electrochemical sensor and optical sensor because of its selectivity to several cations. There was no report on the use of the 18-crown-6-ether as a single coating layer on the QCM sensor. This work investigates the loading effect of the 18-crown-6-ether as a selective coating for QCM sensors as a pre-requirement for a selective coating layer. The impedance spectrum of the QCM sensor coated with 18-crown-6-ether at different concentrations solved in three different solvents was measured. The effects of solvents and 18-crown-6-ether concentrations to the calculated thickness and the effect of the QCM sensor impedance was investigated. The solvents used are Toluene, Tetrahydrofuran (THF), and Chloroform. The results show that the film behaves like a rubber material, which is shown by the impedance value of the sensor at the series resonance frequency. It can be concluded that the thickness of the 18-crown-6-ether layer must be maintained less than one μm to avoid damping on the QCM sensor.
Effect of sulfur and sodium sulfate on phase transformation and microstructure on carbothermic reduction of Indonesian ilmenite
Authors: Setiawan Agung , Harjanto Sri 
Published: July 2020

Abstract
Utilization of ilmenite and pulverized biomass of palm kernel shell is a beneficial solution to deal with the depletion of high-grade titanium minerals and manage of palm oil waste. The purposes of this research are to analysis the phase transformation and microstructure with additive addition. Sulfur and sodium sulfate have used an additive with an additional dosage of 0%, 1.5%, 3.0%, and 4.5%, and the reductant was the pulverized palm kernel shell biomass. The ilmenite concentrate was reduced at 1200 °C for 60 minutes in inert condition (N2 atmosphere). Testing methods performed are Optical microscope (OM), X-Ray diffraction (XRD), Field-Emission Scanning Electron Microscopy (FE-SEM), and Energy Dispersive X-ray spectroscopy (EDX), calculating of the average particle size, and metal recovery. The results showed that the active additive used was sodium sulfate compared to sulfur. At the addition of 4.5 wt.% sodium sulfate, it was obtained phases of titanium suboxide, Ti6O11 and Ti3O5, with very high intensity. Recovery and grades of the reduced sample with 4.5 wt.% sodium sulfate are reached 70.91% and 94.20% Fe, respectively. Moreover, the average particle size of metallic iron increased from 11.96 μm to 38.36 μm with the addition of 4.5wt.% sodium sulfate.
The Fabrication of Zn-Zr Alloy through Centrifugal Casting and Box Furnace Method for Implant Application
Authors: Trinanda Achmad Fauzi , Ghani Fahmi Moh Waqyan , Pratiwi Rizki Yuni , Zakiyuddin Ahmad , Astutiningsih Sotya 
Published: July 2020

Abstract
Recently, zinc (Zn) is extensively observed as biomaterial or biodegradable implant for medical application. A biomaterial is any substance that has been engineered to interact with biological systems for a medical purpose. Zn is chosen because it has moderate degradation compared to Mg and Fe. Unfortunately, Zn has limitation on its mechanical properties that still low. The Alloying element is needed to improve the mechanical properties of Zn. Alloying element, such as zirconium (Zr) can improve the mechanical properties of Zn. In this study the addition of Zr with the composition variations of 0%, 0.5%, 1%, and 2% were used. Two kinds of alloying method used are centrifugal casting and box furnace with a temperature of 550°C. The aims of this study are to know the effect of each fabrication method to the mechanical properties and the result of Zn-Zr alloy microstructures. The results show that the microstructure of the alloy from centrifugal casting is more homogenous than the box furnace method. The mechanical properties of centrifugal casting are also higher than the box furnace method. The hardness value obtained from centrifugal casting of 0, 0.5, 1, 1.5 and 2% of Zr are 35.162 HV, 41.988 HV, 42.324 HV, 57.112 HV, respectively.