bluuebunny/crossref_metadata_2025_split huggingface dataset:
TiO2/Co3O4 nanocomposite: Synthesis via Catharanthus roseus (L.) G. Don leaf extract, characterization and its photocatalytic activity for malachite green degradation
Authors: Syahfitri T W W , Yulizar Y , Gunlazuardi J , Apriandanu D O B 
Published: October 2020

Abstract
TiO2/Co3O4 nanocomposite was successfully synthesized using leaf extract of Catharanthus roseus (L.) G. Don. (CRE), precursors of TTIP and Co(NO3)2. FT-IR characterization shows that TiO2/Co3O4 has been formed due to the presence of secondary metabolites in CRE which have a major role as a weak base source for nanocomposite synthesis. Particle size analysis was employed by PSA and TEM, which were found to be 38.04 nm and 90.80 nm, respectively. Besides, the UV-Vis DRS result shows that TiO2/Co3O4 has bandgap energy at 2.8 eV. According to the morphological analysis, TiO2/Co3O4 nanocomposite has a spherical shape confirmed by SEM. The structural analysis was confirmed by XRD that TiO2/Co3O4 nanocompositehas a diffraction pattern combination of TiO2 and Co3O4 nanoparticle. The photocatalytic activity of TiO2/Co3O4 nanocomposite was examined for malachite green degradation. The result shows that the degradation percentage was 82.61 % under visible light illumination for 120 min.
Nickel ferrite nanocrystalline as a green and recyclable catalyst for the synthesis of Spiro-oxindole-chromene
Authors: Oktavia S H , Cahyana A H , Yunarti R T 
Published: October 2020

Abstract
A separable NiFe2O4 nanocrystalline catalyst was synthesized via a simple co-precipitation method. The catalytic activity of this heterogenous catalyst was investigated to synthesize Spiro-oxindole-chromene derivates via Knoevenagel condensation, and Michael addition reaction under conventional heating condition. The catalyst showed a prominent catalytic activity in a good yield (86.74 %). This easily separated catalyst could be recycled efficiently for four cycles without significant loss of its activity. Furthermore, the products were investigated for the antioxidant activity using DPPH method. The IC50 of the compounds was found to be 182.3 ppm. The use of catalysts has been proven a simple, efficient and environmentally friendly reaction. Based on the results, it is known that the reaction could not be achieved without the presence of NiFe2O4 catalyst.
Preliminary study of electrooxidation isoeugenol into vanillin using platina and boron-doped diamond electrode
Authors: Hilyatudini  , Riyanto H G , Wibowo W , Ivandini T A 
Published: October 2020

Abstract
Vanillin was synthesized from isoeugenol through an electrochemical method using Pt and BDD electrodes using chronoamperometry technique in a one-compartment electrochemical cell. The oxidation at C-C bond termination was expected to occur to form an aldehyde group. The oxidation potential of isoeugenol at Pt and BDD electrodes were fixed at +0.61 V and +0.96 V, respectively. The oxidation results were confirmed by GC, GC-MS, and FTIR. Thin layer chromatography result showed that vanillin could be produced at Pt and BDD electrodes with the yield percentage of 2.9 % and 1.33 %, respectively.
Electroreduction of CO2 using modified boron-doped diamond electrode as the working electrode
Authors: Rahmawati I , Yetri N Y , Gunlazuardi J , Ivandini T A 
Published: October 2020

Abstract
Electroreduction of CO2 becomes a popular study to resolve the problems due to the increase of CO2 in atmosphere. In this work, electroreduction of CO2 was studied using various working electrodes in 0.1 M NaCl solutions. A reduction peak potential around -1.5, -1.1 and -1.2 V, respectively, was observed at BDD, Cu, Cu-BDD, while Cu2O-BDD with different deposition times showed typical peaks at around -1.3 V. Liquid chromatography analysis on the solutions after CO2 electroreduction at the applied potential of -1.3 V (vs Ag/AgCl) showed that by using BDD and Cu electrodes only formic acid and formaldehyde could be produced. However, the use of various Cu2O concentrations deposited on BDD electrodes can produce not only formic acid and formaldehyde, but also acetic acid and methanol with high selectivity of the products, indicating the electrode is promising to have more various products in the electrochemical reduction of CO2.
Sm2O3 nanoparticles preparation using caesalpinia pulcherrima leaf extract, characterization and photocatalytic activity
Authors: Putri N , Yulizar Y , Umar A , Apriandanu D O B 
Published: October 2020

Abstract
In this research, Sm2O3 nanoparticles (NPs) have been prepared via Caesalpinia pulcherrima leaf extract (CPE), whichh contains secondary metabolites contained as a weak base source and a capping agent. The nanoparticles were confirmed by UV-Vis DRS, FT-IR spectroscopy, XRD, PSA and TEM. FT-IR spectrum showed that CPE contains the secondary metabolites which play an essential role in the preparation of Sm2O3 NPs. UV-Vis DRS result showed that the bandgap value of Sm2O3 NPs was approximately 4.76 eV which works in the UV region. Based on the XRD analysis, Sm2O3 NPs have a structure of cubic. PSA characterization showed that the average particle size distribution of Sm2O3 was around 84.47 nm. TEM image confirmed that Sm2O3 was in nanoscale with the particle size of 73.27 nm. Finally, Sm2O3 NPs have been tested for the photodegradation of malachite green (MG) under UV light illumination. The degradation percentage of MG using Sm2O3 NPs photocatalyst was 80.14 % for 2 h.
Investigation on the effect of Zirconium doping on the structural and electrical properties of BiFe1-x
Zr
x
O3 with x = 0.01, 0.03 and 0.05
Authors: Aflahannisa  , Triyono D 
Published: October 2020

Abstract
Multiferroic material was interesting because it has many potential applications in sensors, spintronic devices, actuators, memory devices, microelectronic devices, and convertors. Material multiferroic has two or more primary ferroic properties in the same phase. BiFeO3 is a multiferroic material that has two ferroic properties such as antiferromagnetism and ferroelectricity. BiFe1-xZrxO3 with x = 0.01, 0.03 and 0.05 have been prepared by sol-gel method to study effect structural and electrical properties. X-ray diffraction result shows that all of the samples have a hexagonal structure with space group R3c and lattice parameter, volume, density increased when the concentration of zirconium increased. Zr-substitution caused the dielectric constant decrease when the concentration of Zr increases at a lower frequency.
Microstructure and mechanical properties of magnesium Si3N4 reinforced composite fabricated by stir casting method
Authors: Manggabarani A A D , Syahrial A Z 
Published: October 2020

Abstract
Currently, the development of materials to improve the efficiency of fuel usage is increasingly carried out, one of which is a matrix composite. The stages of making composites in this study started from the preparation of magnesium matrix and Si3N4 reinforcement to casting with a stirring casting method. The addition of Si3N4 reinforce was carried out by varying the volume fraction by 2 vf-%, 4 vf-%, 6 vf-%, and 8 vf-% which was then characterized by metallographic testing, SEM-EDS, tensile testing, hardness, impact, wear, density and porosity, and XRD. The results of this study showed an increase in mechanical properties by adding Si3N4 as reinforcing particles. The magnesium composite produced different mechanical properties in each variation of the addition of the reinforce. The best mechanical properties resulted from the addition of a reinforce is with a volume fraction of 8 vf-% which produced a hardness value of 94 HRH and a wear rate of 0.0045 mm3/m.
An impedance spectroscopy study of sol-gel prepared La0.9Sr0.1Fe0.7Mo0.3O3 perovskite
Authors: Triyono D , Rafsanjani R A , Laysandra H 
Published: October 2020

Abstract
In this present work, impedance spectroscopy was applied to investigate the electrical properties of La0.9Sr0.1Fe0.7Mo0.3O3 (LSFMo) perovskite prepared by sol-gel and sintering methods. SEM analysis reveals the non-uniform grain distributed in samples with average grain size 347 nm. The complex impedance has been examined in the frequency range of 100 Hz–1 MHz and temperature range of 75–250 °C. The Nyquist plots were identified to form single semicircular arc described as grain behavior working in conduction mechanism. The dielectric and complex conductivity is shown depending on the temperature and frequency. The evolution of ln σDC vs 103/T (K−1) satisfies Arrhenius law and the activation energy is found to be 0.45 eV for this conduction mechanism.
A preliminary study on modified chitosan-curcuminoids as material active food packaging with antioxidant and antibacterial activities
Authors: Azkia A , Baihaqi A I , Prabowo H A , Hendri  , Handayani S , Agustiany T 
Published: October 2020

Abstract
The compound of inorganic nanoparticles is commonly mixed with polymeric materials for food packaging that has antibacterial function. However, the inorganic nanoparticles are toxic to human and the polymeric materials used are not easily biodegraded. The curcuminoids compound from turmeric extract has antioxidant and antibacterial activity which can be a candidate as polymer combination. The polymer used is chitosan which isolated from crab shell with the yield of 4.54 %. In this study, the modified chitosan-curcuminoids was synthesized by in-situ loading method and moulded into a film. Interaction between chitosan and curcuminoids is hydrogen interaction which determined using FTIR. Then, antioxidant activity was tested using radical DPPH scavenger. Antioxidant test results showed that modified chitosan with 20, 40, 60 80 and 100 ppm of ascorbic acid have inhibition levels of 15.49, 16.20, 16.90, 23.94 and 27.47 %, respectively. Modified chitosan with 25 ppm of curcuminoids have a comparable antioxidant activity to chitosan modified ascorbic acid 80 ppm with 24.65 % inhibition. Meanwhile, in the antibacterial test, chitosan modified with curcuminoids showed antibacterial activity toward E. coli and S. aureus bacteria with inhibition zone of 9 and 6 mm, respectively.
Methyl orange dye removal using Ni/Fe-NO3 and Ni/Fe-[α-SiW12O40] layered double hydroxides
Authors: Lesbani A , Taher T , Palapa N R , Mohadi R , Yuliana A , Mardiyanto  
Published: October 2020

Abstract
The material of layered double hydroxide (LDH) Ni/Fe-NO3 was prepared by coprecipitation method under basic condition. Ni/Fe LDH was modified by intercalation using K4[α-SiW12O40] to form Ni/Fe-[α-SiW12O40]. All materials were characterized by X-ray and FTIR spectroscopy. Ni/Fe LDH and intercalated Ni/Fe LDH were used as adsorbent of methyl orange dye from the aqueous solution. The parameter of adsorption such as kinetic and also thermodynamic adsorption of methyl orange on LDHs were investigated. X-Ray analysis showed that the diffraction at 11.53 ° [003] of Ni/Fe-NO3 has interlayer distance 7.67 Å shift to 8.20 ° [003] of Ni/Fe-[α-SiW12O40] with interlayer distance 10.78 Å. FTIR spectra of Ni/Fe-NO3 and Ni/Fe-[α-SiW12O40] show the wavenumber at 1600 cm−1 due to vibration of LDHs anion. Adsorption of methyl orange onto Ni/Fe-NO3 and Ni/Fe-[α-SiW12O40] follow the pseudo second-order kinetic model, where intercalated material has a higher reactivity than Ni/Fe-NO3 before intercalation. Isotherm model Freundlich was more fitted than isotherm Langmuir for the adsorption of methyl orange on LDHs with multilayer physical adsorption process. Adsorption capacity of methyl orange on Ni/Fe-[α-SiW12O40] as adsorbent was slightly higher (up to 7.226 mg.g−1) than Ni/Fe-NO3 as adsorbent (3.190 mg.g−1).
Conversion of delignified stem sorghum bicolor into levulinic acid using micro and mesoporous ZSM-5 catalysts
Authors: Siregar Y D I , Saepudin E , Krisnandi Y K 
Published: October 2020

Abstract
Sorghum bicolor stem is one of the biomass wastes that can be used as raw material for synthesizing platform chemicals. Levulinic acid is one of the chemicals that is currently a substance often synthesized or isolated. Levulinic acid can be catalytically synthesized from sorghum stem waste which is rich in cellulose. Cellulose in the sorghum stem is still bound to lignin and hemicellulose, therefore pretreatment is needed to reduce lignin. The method consists of pretreatment of biomass by delignification, manufacturing of micro and mesoporous ZSM-5 catalysts (double template method) and the reaction of the conversion of stem sorghum to levulinic acid is carried out in a mini reactor. Catalyst characterizations were conducted using FTIR, XRD, SEM EDX and product analysis by HPLC. The result of delignification is the cellulose content increased from 45.10 % to 76.66 %. The result of as-synthesized ZSM-5 showed the diffractogram patterns similar to the standard ZSM-5. SEM image showed a hexagonal coffin-like shape which is the characteristic of ZSM-5. The levulinic acid produced using meso-porous ZSM-5 catalyst was observed at the reaction time of 2–6 h, while the yield of levulinic acid using micro-porous ZSM-5 catalyst was observed at the end of the reaction time, i.e. 6–10 h. It can be concluded that the pore size of the catalyst and the duration of the conversion time influenced the yield of levulinic acid.
Electronic structure of 9 quintuple layers Bi2Se3 within Density Functional Theory
Authors: Hasan M , Majidi M A 
Published: October 2020

Abstract
Bismuth Selenide (Bi2Se3) is a well-known 3D-type topological insulator. The interior part of this material is insulating, while its surface state is metallic which is protected by time-reversal symmetry. The experimental study of this material by varying its thickness reveals that the metallic surface state starts to appear at a minimum thickness of six Quintuple Layer (QL). This study was performed within the Density Functional Theory (DFT) in which a vacuum gap is added to the multilayer structure in order to capture the surface states of the material. While a previous study has explored the electronic structure of this material upto a thickness of 8 QL, a more detailed information of how the system evolves from this thickness to a fully bulk limit has not much been explored. With this motivation, we propose to calculate the electronic structure of this material with thickness of 9 QL. We perform the DFT calculation using Quantum Espresso (QE) package. Our results show that the band structure of this system reveals the surface metallic states with many additional bands as compared to those of thinner layer systems.
Simulation of CuO/ZnO heteroj unction for photovoltaic applications
Authors: Abdelfatah Mahmoud , El-Shafai Nagi M. , Ismail Walid , El-Mehasseb Ibrahim M. , El-Shaer Abdelhamid 
Published: October 2020

Abstract
Inorganic semiconductors become one of the most gifted candidate for photovoltaic applications instead of high cost silicon devices and organics ones. Therefore, in this paper, inorganic CuO/ZnO heteroj unction is simulated as thin layer solar cells employing SCAPS program. Both effect of CuO and ZnO layers thickness on basic parameters of solar cells is investigated deeply. Simulated results of this solar cell device indicate that the absorber layer is responsible for separation process of generated carriers. Higher efficiency of about 23 % could be achieved with 2 μ of CuO thickness and 100 nm of ZnO layer for devices. Generally, the main aspects that controlling the solar cell performance are depletion region width, built-in potential, the charge carrier collection length and generation and recombination rates.
Gold Nanorods as Contrast Agent for Photoacoustic Imaging (PAI) of Breast Cancer
Authors: Awad H , Abdallah T , Easawi K , Negm S , Talaat H 
Published: October 2020

Abstract
Gold Nanorods (AuNRs) can play a fundamental role in the enhancement of photoacoustic imaging (PAI). This is due to their high and tunable optical absorption cross-section. Normally, the most convenient and highly stable AuNRs are synthesized using Cetyltrimethylammonium bromide (CTAB) as a surfactant. In this work, surface modification with poly ethylene glycol (PEGylation) and Silica coating (SiO2-coating) were applied to help in reducing toxicity of CTAB capped AuNRs. Breast cancer cell line (MDA-MB-231) was used to assess the modified AuNRs as contrast agents. A much brighter PAI of cells loaded with SiO2-coated AuNRs was obtained. Such an enhanced PA image is due to the larger cellular uptake, as observed from bright field microscope images taken for the cells. On the other hand, the corresponding PA image for cells with PEGylated AuNRs is diminished. The increase in cell uptake, in case of SiO2-coated AuNRs, could result due to the adsorption of protein, contained in the cell culture media, on the negatively charged silica surface, which increases intercellular uptake by receptor-mediated endocytosis. Moreover, the increase of the brightness of PAI of SiO2-coated AuNRs may be due to the lowering of the interfacial thermal resistance between gold and the surrounding solvent. This allows the particle to release more heat to its environment which increases the generated acoustic signals from these particles.
Plasmonic Yolk-Shell Nano Structures for Solar Cells Absorbance Enhancement
Authors: AbdelAziz Hadeer H. , Ali Tamer A. , Rafat Nadia H. 
Published: October 2020

Abstract
In this research we study the enhancement in power absorbance of thin film silicon solar cells by plasmonic yolk-shell (YS) nano particles. Plasmonic YS nano particles are simulated on top/bottom position of thin film Si layers. We suggest different structures of YS and simulate the behaviour of such structures using a FDTD simulations. We calculate the limiting photocurrent taking into consideration the enhanced absorbance of the cell. The simulation results show multi-peaked and broad band power absorbance enhancement all over the solar spectrum. The power absorbance enhanced into solar cell by 64% over planar ultra-thin 300 nm Si cell.
Efficient light harvesting in perovskite layer via three-dimensional TiO2 nanobranched nanorod scaffold
Authors: Daneshvar e Asl Shervin , Zarenezhad Hamaneh , Askari Masoud , Halali Mohammad , Sadrnezhaad Sayed Khatiboleslam 
Published: October 2020

Abstract
A comparative study was done on three types of TiO2 thin film morphology, i.e., mesoporous nanoparticles, nanorods, and nanobranched nanorods thin films, as the scaffold for the perovskite solar cell. The performances of the perovskite-coated thin films were compared in terms of charge carrier extraction, charge transport, and solar energy harvesting via photoluminescence and UV–vis spectroscopies. TiO2 nanobranched nanorods thin film showed better photovoltaic performance than those of mesoporous nanoparticles and nanorods thin films. The better optical properties of nanobranched nanorods thin film as the scaffold is ascribed to its unique morphological advantages, i.e., remarkable specific surface area along with high-speed pathways for charge carriers. These characteristics lead to great, compact, and uniform perovskite loading, excellent electron transport property, and desired light harvesting performance, which are preferable features for promoting the efficiency of the perovskite solar cells. This paper introduces an outstanding scaffold for fabrication of high-performance perovskite solar cells.
Reliability of the Dilute Russel Viper Venom Time (dRVVT) in Determining Lupus Anticoagulant (LAC) in Anticoagulated Patients
Authors: Khan Waleed , Rinder Henry , Tormey Christopher , Siddon Alexa 
Published: October 2020

Abstract

Objectives
Antiphospholipid syndrome (APS) can be complicated by thrombosis in the presence of laboratory evidence of persistent antiphospholipid antibodies, usually in the form of a LAC. The diagnostic criteria for APS/LAC require persistent prolongation of two phospholipid-dependent clotting assays, most often the dRVVT and a thromboplastin-based phospholipid-neutralization (PN) assay. When there is discrepancy between tests, LAC diagnosis is inconclusive. This testing is complicated by anticoagulation, which may yield false positive results. We investigated the impact of various anticoagulants on LAC diagnosis by evaluating the rates of dRVVT and PN discrepancy between anticoagulated and non-anticoagulated patients.

Methods
dRVVT and PN (LAC panel) values were examined for 1452 consecutive patients samples since April 2017, along with anticoagulant status at the time of testing. Each LAC panel was classified as positive (both dRVVT and PN abnormal), negative (both dRVVT and PN normal), or discrepant (one normal and one abnormal). The proportion of discrepant results between anticoagulated and non-anticoagulated patients was calculated and also stratified according to the class of anticoagulant.

Results
Discrepant results occurred in 161 of 493 anticoagulated patient samples (33%) versus 135 of 1012 non-anticoagulated patient samples (13%). The odds ratio (OR) for a discrepant result for anticoagulated patient samples was 3.15 (95% CI=2.43–4.09) compared to non-anticoagulated patient samples. When narrowed to individual anticoagulant classes, Lovenox had the lowest chance of yielding discrepant results (OR = 1.16 95% CI= 0.51–2.66), whereas Rivaroxaban (OR = 6.9 95% CI= 4.49–10.55) and Warfarin (OR = 5.4 95% CI= 3.43–8.55) had the highest odds of yielding discrepant results.

Conclusions
Patient anticoagulant status is an important determinant in laboratory testing for APS/LAC. The dRVVT and PN test are 3-fold more likely to yield inconclusive results when a patient is anticoagulated; the type of anticoagulant is even more critical given the large difference in rates of discrepant results for patients on Rivaroxaban and Warfarin versus patients on Lovenox. The difference in discrepancy rate is likely due to the differential impact of each class of anticoagulant on the various components of the coagulation cascade. Rivaroxaban is a direct factor X inhibitor, and Warfarin directly lowers active factor X, amongst other, levels; by contrast, Lovenox, which was not significantly discrepant, requires antithrombin to amplify inhibition of factor II and X activity.