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The Effect of Aloe vera Extract Variation in Electrospun Polyvinyl Alcohol (PVA)-Aloe vera-Based Nanofiber Membrane

Journal of physics: Conference Series 2018年第1期1120卷

作者： D Hikmawati A R Rohmadanik A P Putra Siswanto Aminatun Physics Study Program Department of Physics Faculty of Science and Technology Universitas Airlangga Surabaya 61110 Indonesia Biomedical Engineering Study Program Department of Physics Faculty of Science and Technology Universitas Airlangga Surabaya 61110 Indonesia

Electrospinning technique is a method to produce nanofiber with high potential difference. Several main parameters in the electrospinning process are solution parameter, such as viscosity, surface tension and conductivity. Those parameters affect the morphology of nanofiber membrane produced by the electrospinning process. This study used 10% PVA in aquadest with several Aloe vera concentration (0, 2.5, 5, 7.5 and 10 % w/v). The viscosity of the solution increased when the concentration of the Aloe vera increased. SEM image of the nanofiber membrane showed that the diameter of the nanofiber increased with the increase of the Aloe vera concentration, with the highest diameter of 379.80 nm on the membrane with Aloe vera concentration of 10% w/v. The result of DSC test showed that there were shifts on the glass transition (Tg) and melting point (Tm) value along with the addition of Aloe vera in the PVA solution. This results was also emphasized with the result of FTIR test which showed the shift on the wavenumber absorbance due to the crosslinking between PVA and Aloe vera. The degradation test indicated that the presence of crosslinking could maintain the nanofiber structure, thus the membrane was not easily degraded.

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Response of Gravity, Magnetic, and Geoelectrical Resistivity Methods on Ngeni Southern Blitar Mineralization Zone

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Journal of physics: Conference Series 2018年第1期979卷

作者： Sunaryo Geophysical Engineering Program Study Physics Department Sciences Faculty University of Brawijaya Malang Indonesia

The research with entitle response of gravity, magnetic, and geoelectrical resistivity methods on Ngeni Southern Blitar mineralization zone has been done. This study aims to find the response of several geophysical methods of gravity, magnetic, and geoelectrical resistivity in an integrated manner. Gravity data acquisition was acquired 224 data which covers the whole region of Blitar district by using Gravity Meter La Coste & Romberg Model 'G', and magnetic data acquisition were acquired 195 data which covers the southern Blitar district only by using Proton Precession Magnetometer G-856. Meanwhile geoelectrical resistivity data only done in Ngeni village which is the location of phyropilite mining with the composition content of Fe, Si, Ca, S, Cu, and Mn by using ABEM Terrameter SAS 300C. Gravity data processing was performed to obtain the Bouguer anomaly value, which included unit conversion, tidal correction, drift correction, correction of tie point, base station correction, free air correction, and Bouguer correction. Magnetic data processing has been done by some corrections i.e daily, drift, and IGRF(International Geomagnetic Refference Field) to obtain the total magnetic anomaly. From gravity data processing has been obtained the simple Bouguer anomaly value in range from -10mGal until 115mGal. From this data processing has been obtained the total magnetic anomaly value in range from -650nT until 800nT. Meanwhile from geoelectrical resistivity 3.03Ωm until 11249.91 Ωm. There is a correlation between gravity anomaly, magnetic anomaly, and geoelectrical resistivity anomaly that are associated with deep anomaly, middle anomaly, and shallow anomaly.

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Identification of lithology properties of groundwater by using resistivity method in Girimulyo, Kulon Progo, Yogyakarta

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Journal of physics: Conference Series 2019年第1期1153卷

作者： Nurul Dzakiya F D Sastrawan R B Laksmana M M Anan Amara SA Geological Engineering Department of Institut Sains & Teknologi AKPRIND Yogyakarta Jl. Kalisahak No 28 Gondokusuman Yogyakarta 55222 INDONESIA Physics Study Program of Institut Teknologi Kalimantanv KM 15 Karang Joang North Balikpapan East Kalimantan 76127 INDONESIA

Identification of lithology properties of groundwater has been done in Nglengkeh and surrounding area, Pendoworejo Village, Girimulyo District, Kulon Progo, Special Region of Yogyakarta. There are 13 points survey (ST) with long of 80-250 meters spread across the surface. This measurement is done in Nanggulan Claystone and Old Andesit Intrusion which each have widh 71.8% and 6.3% of the total research area. Nanggulan Claystone consists of claystone, siltstone and sandstone while The Old Andesite Intrusion consists of andesites. The results of interpretation resistivity data indicate three lithology properties to groundwater are aquiclude, aquifer and aquifuge. This area are dominated by aquiclude that consist of siltstone with resistivity 12-25 Ωm and claystone 1-10 Ωm at depth 3 meters and 25 meters. Rocks, as aquifers, are sandstones and siltclay. The type of aquifer identified is unconfined aquifer of soil by the name of silt clay with resistivity 14-20 Ωm at a depth of about 23 meters. Sandstone as confined aquifer with resistivity 25-75 Ωm in depth of 25-45 meters. Aquifuge which consist of andesite intrusion has resistivity 380-1984 Ωm. It was found only in ST 11 at depth ± 35 meters and ST 12 at depth ± 80 meters. The variations lithology properties to groundwater and unconfirmity of a sedimentary layer in the reseach area are controlled by stratigraphic parameters and exogenic processes (weathering and erosion).

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Preparation Of Superhydrophobic Zinc Oxide Nanorods Coating On Stainless Steel Via Chemical Bath Deposition

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IOP Conference Series: Materials Science and engineering 2019年第1期547卷

作者： Ahmad Nuruddin Brian Yuliarto Santi Kurniasih Henry Setiyanto Aditianto Ramelan Engineering Physics Research Group Faculty of Industrial Technology Institut Teknologi Bandung Bandung 40132 Indonesia Materials Engineering Study Program Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Jalan Ganesha 10 Bandung 40132 Indonesia Analytical Chemistry Research Group Faculty of Mathematics and Sciences Institut Teknologi Bandung Bandung 40132 Indonesia

The stearic acid modified zinc oxide nanorod surface was coated with a stainless steel substrate to improve the contact angle and the sliding angle. Facilitated through ZnO seeding on the substrate, the ZnO nanorod was deposited via chemical bath deposition at different precursor concentrations. The surface hydrophobicity was modified by varying concentrations of stearic acid at and submmersion time. The contact angle was investigated in relation to the surface microstructure and modification. Results indicate that the density of ZnO nanorods on the substrate surface and stearic acid coverage are prerequisites for improving surface hydrophobicity. Superhydrophobic properties with a contact angle of 162° was obtained for ZnO deposited with 35 mM zinc nitrate and submerged in 8 mM stearic acid for 36 h, which allowed 5 μL water droplets to slide at 3.8°.

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Optimization of Frequency and Stirring Rate for Synthesis of Magnetite (Fe 3 O 4 ) Nanoparticles by Using Coprecipitation- Ultrasonic Irradiation Methods

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Procedia engineering 2017年 170卷 55-59页

作者： Retno Rahmawati Mohammad Gilang Permana Bill Harison Nugraha Brian Yuliarto Suyatman Deddy Kurniadi Engineering Physics Department Faculty of Industrial Technology ITB Bandung 40132 Indonesia Physics Study Program Faculty of Sains and Technology UIN SunanKalijaga Yogyakarta 55281 Indonesia

Magnetite (Fe 3 O 4 ) nanoparticles from iron sand as starting materials have been successfully synthesized by using coprecipitation- ultrasonicirradiation methods. This paper reports the preparation and optimization result of ultrasonic frequency and stirring rate during the synthesis process. The frequencies of ultrasonic conducted in this research are 300, 400 and 400 kHz. The stirring rates performed in the synthesis process are varied from 500 to 900 rpm. The qualitative analysis by using X-Ray Diffractometer (XRD) showed that the structure of Fe 3 O 4 nanoparticles have a same phase with ICCD No. 75-0449. Moreover, the quantitative analysis by using Debye-Scherer equation showed that the crystallite size of Fe 3 O 4 ranging from 21 to 25 nm depend on the ultrasonic frequency and stirring rate. Meanwhile, the transmission electron microscopy (TEM) result revealed that the Fe 3 O 4 tend to form spherical shape with little agglomeration on the morphology of the Fe 3 O 4 . The magnetic properties of Fe 3 O 4 were investigated by using vibrating sample magnetometer (VSM). The VSM measurement result showed that the Fe 3 O 4 have saturation magnetization (Ms), remanent magnetization (Mr) and coercivity field (Hc) at 25 emu/gram, 6,0562 emu/gram, and 0,0108 T, respectively. Based on the magnetic characterization, the Fe 3 O 4 nanoparticles have a potential to be appliedin biomedical field.

关键词： coprecipitation-irradiation ultrasonic Fe 3 O 4 iron sand optimization

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Monitoring electrical energy in electronic energy audits through internet of things technology

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Journal of physics: Conference Series 2019年第7期1402卷

作者： M P T Sulistyanto K B Pranata A N Afandi S Sendari I Sulistiyowati Informatics Study Program Faculty of Science and Technology Universitas Kanjuruhan Malang Jl. S. Supriadi No. 48 Malang Jawa Timur Indonesia Physics Education Study Program Faculty of Science and Technology Universitas Kanjuruhan Malang Jl. S. Supriadi No. 48 Malang Jawa Timur Indonesia Department of Electrical Engineering Faculty of Engineering Universitas Negeri Malang Teknik Elektro Universitas Muhammadiyah Sidoarjo Jl. Raya Gelam 250 Candi Sidoarjo Jawa Timur Indonesia

Energy conservation, especially electricity, can be done by conducting an energy audit. Energy audit activities can analyse and find energy-saving opportunities from energy use. This study developed a prototype of a wireless electrical energy monitoring system on a laboratory scale to monitor the use of electrical energy from both electrical equipment using a microcontroller as a sensor node. These nodes have installed several sensors, namely the current sensor, humidity sensor, temperature sensor and light sensor. The protocol used in communication between nodes and servers is the HTTP protocol in the Internet of Things design that can communicate using internet network intermediaries. Data on the server can be monitored in real time using the application on the client side.

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Preparation of cellulose nanocrystals from empty fruit bunch of palm oil by using phosphotungstic acid

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IOP Conference Series: Earth and Environmental Science 2018年第1期105卷

作者： Y W Budhi M Fakhrudin N T U Culsum V Suendo F Iskandar Chemical Engineering Study Program Faculty of Industrial Technology Bandung Institute of Technology Bandung 40132 Indonesia Chemistry Study Program Faculty of Mathematic and Science Bandung Institute of Technology Bandung 40132 Indonesia Physics Study Program Faculty of Mathematic and Science Bandung Institute of Technology Bandung 40132 Indonesia

Empty fruit bunch (EFB) of palm oil, an abundant agro-waste in Indonesia, was used as raw material of Cellulose Nanocrystals (CNCs) preparation. Instead of conventional acid mineral, phosphotungstic acid (H3PW12O40, HPW) was used to hydrolyze cellulose due to recycling ability and easy handling. Before hydrolysis process, dried EFB was treated by 3% NaOH solution at 90°C for 2 hours and then bleached using 2% NaClO2 solution at 80°C for 3 hours to remove hemicellulose and lignin. Hydrolysis reaction parameters such as temperature, acid concentration, and reaction time were optimized with fixed solid-liquid ratio of 1:40. Response surface method was used for experimental design to determine the optimum condition of each parameter by using software Minitab. In this study, pulp from dried EFB produced 44.8% yield of CNCs. Dynamic Light Scattering (DLS) analysis showed that most of CNCs equivalent diameter was 140 nm. Crystallinity index was observed at 73.3% using X-ray Diffraction (XRD) analysis. Thus, a green established process for the preparation of CNCs was achieved.

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High-Temperature Oxidation Behavior of Fe-18Al Alloy Added with 2 %ZrO2 Nanoparticles

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IOP Conference Series: Materials Science and engineering 2019年第1期515卷

作者： P Pawawoi D H Prajitno A A Dewi A Manaf Postgraduate Program of Materials Science Study Department of Physics Faculty of Mathematics and Natural Sciences Universitas Indonesia Depok 16514 PTNBR- BATAN Jln. Tamansari 71 Bandung 40317 Bandung Metallurgical Engineering of Jenderal Achmad Yani University Jln. Gatot Subroto PO. Box 807 Bandung 40285

The oxidation behaviour of ZrO2 nanoparticles added to Fe-18Al alloy has been studied. Isothermal oxidation behaviour with various temperatures and times was investigated and the results of microstructure showed the presence of Fe3Al intermetallic phases in grey color, Al2O3 oxide in white color, and the porosity indicated by dark color. The results of XRD and SEM-EDS analysis also confirmed the presence of the ZrO2 nanoparticles in addition to Fe3Al intermetallic phases and Al2O3 oxide phases. The addition of ZrO2 nanoparticles tended to decrease oxidation rate by promoting Al2O3 layers.

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The electron-capture origin of supernova 2018zd

arXiv

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arXiv 2020年

作者： Hiramatsu, Daichi Howell, D. Andrew van Dyk, Schuyler D. Goldberg, Jared A. Maeda, Keiichi Moriya, Takashi J. Tominaga, Nozomu Nomoto, Ken'ichi Hosseinzadeh, Griffin Arcavi, Iair McCully, Curtis Burke, Jamison Bostroem, K. Azalee Valenti, Stefano Dong, Yize Brown, Peter J. Andrews, Jennifer E. Bilinski, Christopher Williams, G. Grant Smith, Paul S. Smith, Nathan Sand, David J. Anand, Gagandeep S. Xu, Chengyuan Filippenko, Alexei V. Bersten, Melina C. Folatelli, Gastón Kelly, Patrick L. Noguchi, Toshihide Itagaki, Koichi Las Cumbres Observatory 6740 Cortona Drive Suite 102 GoletaCA93117-5575 United States Department of Physics University of California Santa BarbaraCA93106-9530 United States Caltech/Spitzer Science Center Caltech IPAC Mailcode 100-22 PasadenaCA91125 United States Department of Astronomy Kyoto University Kitashirakawa-Oiwake-cho Sakyo-ku Kyoto606-8502 Japan University of Tokyo Institutes for Advanced Study University of Tokyo 5-1-5 Kashiwanoha Kashiwa Chiba277-8583 Japan National Astronomical Observatory of Japan National Institutes of Natural Sciences 2-21-1 Osawa Mitaka Tokyo181-8588 Japan School of Physics and Astronomy Faculty of Science Monash University ClaytonVIC3800 Australia Department of Physics Faculty of Science and Engineering Konan University 8-9-1 Okamoto Hyogo Kobe658-8501 Japan Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138-1516 United States School of Physics and Astronomy Tel Aviv University Tel Aviv69978 Israel CIFAR Azrieli Global Scholars Program CIFAR Toronto Canada Department of Physics University of California 1 Shields Ave DavisCA95616-5270 United States Mitchell Institute for Fundamental Physics and Astronomy Texas A&M University College StationTX77843 United States Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721-0065 United States MMT Observatory P.O. Box 210065 TucsonAZ85721-0065 United States Infrared Processing and Analysis Center California Institute of Technology PasadenaCA91125 United States Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Media Arts and Technology University of California Santa BarbaraCA93106-6065 United States Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States CONICET Argentina Facultad de Ciencias Astronómi

In the transitional mass range (∼ 8-10 solar masses) between white dwarf formation and iron core-collapse supernovae, stars are expected to produce an electron-capture supernova. Theoretically, these progenitors are thought to be super-asymptotic giant branch stars with a degenerate O+Ne+Mg core, and electron capture onto Ne and Mg nuclei should initiate core collapse1,2,3,4. However, no supernovae have unequivocally been identified from an electron-capture origin, partly because of uncertainty in theoretical predictions. Here we present six indicators of electron-capture supernovae and show that supernova 2018zd is the only known supernova having strong evidence for or consistent with all six: progenitor identification, circumstellar material, chemical composition5,6,7, explosion energy, light curve, and nucleosynthesis8,9,10,11,12. For supernova 2018zd, we infer a super-asymptotic giant branch progenitor based on the faint candidate in the pre-explosion images and the chemically-enriched circumstellar material revealed by the early ultraviolet colours and flash spectroscopy. The light-curve morphology and nebular emission lines can be explained by the low explosion energy and neutron-rich nucleosynthesis produced in an electron-capture supernova. This identification provides insights into the complex stellar evolution, supernova physics, cosmic nucleosynthesis, and remnant populations in the transitional mass range. Copyright © 2020, The Authors. All rights reserved.

关键词： Supernovae

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The palomar transient factory core-collapse supernova host-galaxy sample. I. Host-galaxy distribution functions and environment-dependence of CCSNe

arXiv

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arXiv 2020年

作者： Schulze, Steve Yaron, Ofer Sollerman, Jesper Leloudas, Giorgos Gal, Amit Wright, Angus H. Lunnan, Ragnhild Gal-Yam, Avishay Ofek, Eran O. Perley, Daniel A. Filippenko, Alexei V. Kasliwal, Mansi M. Kulkarni, Shri R. Nugent, Peter E. Quimby, Robert M. Sullivan, Mark Strothjohann, Nora Linn Arcavi, Iair Ben-Ami, Sagi Bianco, Federica Bloom, Joshua S. De, Kishalay Fraser, Morgan Fremling, Christoffer U. Horesh, Assaf Johansson, Joel Kelly, Patrick L. Knežević, Sladjana Maguire, Kate Nyholm, Anders Papadogiannakis, Seméli Petrushevska, Tanja Rubin, Adam Yan, Lin Yang, Yi Adams, Scott M. Bufano, Filomena Clubb, Kelsey I. Foley, Ryan J. Green, Yoav Harmanen, Jussi Ho, Anna Y.Q. Hook, Isobel M. Hosseinzadeh, Griffin Howell, D. Andrew Kong, Albert K.H. Kotak, Rubina Matheson, Thomas McCully, Curtis Milisavljevic, Dan Pan, Yen-Chen Poznanski, Dovi Shivvers, Isaac van Velzen, Sjoert Department of Particle Physics and Astrophysics Weizmann Institute of Science 234 Herzl St Rehovot76100 Israel Department of Astronomy Oskar Klein Centre Stockholm University AlbaNova Stockholm10691 Sweden DTU Space National Space Institute Technical University of Denmark Elektrovej 327 Kgs. LyngbyDK-2800 Denmark Department of Physics of Complex Systems Weizmann Institute of Science 234 Herzl St Rehovot76100 Israel Ruhr-Universität Bochum Astronomisches Institut German Centre for Cosmological Lensing Universitätsstr. 150 Bochum44801 Germany Astrophysics Research Institute Liverpool John Moores University 146 Brownlow Hill LiverpoolL3 5RF United Kingdom Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Senior Fellow Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States Division of Physics Mathematics and Astronomy California Institute of Technology PasadenaCA91125 United States Cahill Center for Astrophysics California Institute of Technology 1200 E. California Blvd PasadenaCA91125 United States Lawrence Berkeley National Laboratory 1 Cyclotron Road MS 50B-4206 BerkeleyCA94720 United States Department of Astronomy / Mount Laguna Observatory San Diego State University 5500 Campanile Drive San DiegoCA92812-1221 United States University of Tokyo Institutes for Advanced Study University of Tokyo KashiwaChiba277-8583 Japan School of Physics and Astronomy University of Southampton SouthamptonSO17 1BJ United Kingdom School of Physics and Astronomy Tel Aviv University Tel Aviv69978 Israel CIFAR Azrieli Global Scholars program CIFAR Toronto Canada Department of Physics and Astronomy University of Delaware NewarkDE19716 United States Joseph R. Biden Jr. School of Public Policy and Administration University of Delaware NewarkDE19716 United States Data Science Institute University of Delaware NewarkDE19716 United States Center for Urban

Several thousand core-collapse supernovae (CCSNe) of different flavors have been discovered so far. However, identifying their progenitors has remained an outstanding open question in astrophysics. Studies of SN host galaxies have proven to be powerful in providing constraints on the progenitor populations. In this paper, we present all CCSNe detected between 2009 and 2017 by the Palomar Transient Factory. This sample includes 888 SNe of 12 distinct classes out to redshift z ≈ 1. We present the photometric properties of their host galaxies from the far-ultraviolet to the mid-infrared and model the host-galaxy spectral energy distributions to derive physical properties. The galaxy mass functions of Type Ic, Ib, IIb, II, and IIn SNe ranges from 105 to 1011.5 M☉, probing the entire mass range of star-forming galaxies down to the least-massive star-forming galaxies known. Moreover, the galaxy mass distributions are consistent with models of star-formation-weighted mass functions. Regular CCSNe are hence direct tracers of star formation. Small but notable differences exist between some of the SN classes. Type Ib/c SNe prefer galaxies with slightly higher masses (i.e., higher metallicities) and star-formation rates than Type IIb and II SNe. These differences are less pronounced than previously thought. H-poor SLSNe and SNe Ic-BL are scarce in galaxies above 1010 M☉. Their progenitors require environments with metallicities of Copyright © 2020, The Authors. All rights reserved.

关键词： Galaxies

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