cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Vertical Structure of the Outer Accretion Disk in Persistent Low-Mass X-Ray Binaries
Creators: name: Mescheryakov, Alexander V.
name: Shakura, Nikolai I.
name: Suleimanov, Valery F.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We have investigated the influence of X-ray irradiation on the vertical structure of the outer accretion disk in low-mass X-ray binaries by performing a self-consistent calculation of the vertical structure and X-ray radiation transfer in the disk. Penetrating deep into the disk, the field of scattered X-ray photons with energy $E\gtrsim10$\,keV exerts a significant influence on the vertical structure of the accretion disk at a distance $R\gtrsim10^{10}$\,cm from the neutron star. At a distance $R\sim10^{11}$\,cm, where the total surface density in the disk reaches $Σ_0\sim20$\,g\,cm$^{-2}$, X-ray heating affects all layers of an optically thick disk. The X-ray heating effect is enhanced significantly in the presence of an extended atmospheric layer with a temperature $T_{atm}\sim(2\div3)\times10^6$\,K above the accretion disk. We have derived simple analytic formulas for the disk heating by scattered X-ray photons using an approximate solution of the transfer equation by the Sobolev method. This approximation has a $\gtrsim10$\,% accuracy in the range of X-ray photon energies $E<20$\,keV.
description: 19 pages, 8 figures, published in Astronomy Letters
GRAPHENE-BASED TERNARY NANOCOMPOSITES FOR PHOTOCATALYTIC WATER SPLITTING
Creators: name: ZHOUYOU WANG
Publisher: name: Monash University
Year: 2018
Subjects: subject: 90499 Chemical Engineering not elsewhere classified
subject: FOS: Chemical engineering

description: Energy shortage and growing environmental pollution are among the humanity's greatest challenges. Technology to directly convert solar energy into chemical energy has been regarded as one of the most promising sustainable and clean energy sources. Significant efforts have been made to search for materials that can achieve high energy conversion. So far, titanium dioxide / metal system and titanium dioxide / graphene system are among the most studied materials. This Ph.D. dissertation aims to address some of the disadvantages observed in these systems by designing an unique structure based on titanium dioxide/ metal /graphene system with high energy conversion.
Homogenous and heterogeneous magnetism in (Zn,Co)O
Creators: name: Sawicki, M.
name: Guziewicz, E.
name: Lukasiewicz, M. I.
name: Proselkov, O.
name: Kowalik, I. A.
name: Lisowski, W.
name: Dluzewski, P.
name: Wittlin, A.
name: Jaworski, M.
name: Wolska, A.
name: Paszkowicz, W.
name: Jakiela, R.
name: Witkowski, B. S.
name: Wachnicki, L.
name: Klepka, M. T.
name: Luque, F. J.
name: Arvanitis, D.
name: Sobczak, J. W.
name: Krawczyk, M.
name: Jablonski, A.
name: Stefanowicz, W.
name: Sztenkiel, D.
name: Godlewski, M.
name: Dietl, T.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A series of (ZnO)m(CoO)n digital alloys and superlattices grown by atomic layer deposition has been investigated by a range of experimental methods. The data provide evidences that the Co interdiffusion in the digital alloy structures is sufficient to produce truly random Zn1-xCoxO mixed crystals with x up to 40%. Conversely, in the superlattice structures the interdiffusion is not strong enough to homogenize the Co content along the growth direction results in the formation of (Zn,Co)O films with spatially modulated Co concentrations. All structures deposited at 160\circC show magnetic properties specific to dilute magnetic semiconductors with localized spins S = 3/2 coupled by strong but short range antiferromagnetic interactions that lead to low temperature spin-glass freezing. It is demonstrated that ferromagnetic-like features, visible exclusively in layers grown at 200\circC and above, are associated with an interfacial mesh of metallic Co granules residing between the substrate and the (Zn,Co)O layer. This explains why the magnitude of ferromagnetic signal is virtually independent of the film thickness as well as elucidates the origin of magnetic anisotropy. Our conclusions have been derived for layers in which the Co concentration, distribution, and aggregation have been determined by: secondary-ion mass spectroscopy, electron probe micro-analysis, high-resolution transmission electron microscopy with capabilities allowing for chemical analysis; x-ray absorption near-edge structure; extended x-ray absorption fine-structure; x-ray photoemission spectroscopy, and x-ray circular magnetic dichroism. Macroscopic properties of these layers have been investigated by superconducting quantum interference device magnetometery and microwave dielectric losses allowing to confirm the important role of metallic inclusions.
description: 23 pages, 22 figures
How long does it take to form a molecular cloud?
Creators: name: Clark, Paul C.
name: Glover, Simon C. O.
name: Klessen, Ralf S.
name: Bonnell, Ian A.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the first numerical simulations that self-consistently follow the formation of dense molecular clouds in colliding flows. Our calculations include a time-dependent model for the H2 and CO chemistry that runs alongside a detailed treatment of the dominant heating and cooling processes in the ISM. We adopt initial conditions characteristic of the warm neutral medium and study two different flow velocities - a slow flow with v = 6.8 km/s and a fast flow with v = 13.6 km/s. The clouds formed by the collision of these flows form stars, with star formation beginning after 16 Myr in the case of the slower flow, but after only 4.4 Myr in the case of the faster flow. In both flows, the formation of CO-dominated regions occurs only around 2 Myr before the onset of star formation. Prior to this, the clouds produce very little emission in the J = 1 -> 0 transition line of CO, and would probably not be identified as molecular clouds in observational surveys. In contrast, our models show that H2-dominated regions can form much earlier, with the timing depending on the details of the flow. In the case of the slow flow, small pockets of gas become fully molecular around 10 Myr before star formation begins, while in the fast flow, the first H2-dominated regions occur around 3 Myr before the first prestellar cores form. Our results are consistent with models of molecular cloud formation in which the clouds are dominated by "dark" molecular gas for a considerable proportion of their assembly history.
description: 16 pages, 10 figures. Submitted to MNRAS
title: Der Menschenrechtsausschuss der Vereinten Nationen und die Klimakrise
title: Die Entscheidung Billy et al. gegen Australien und ihr Beitrag zur „Begrünung“ des Menschenrechtsschutzes
titleType: Subtitle
Creators: name: Buser, Andreas
Publisher: name: Universitätsverlag Potsdam
Year: 2023
Subjects: subject: 340 Recht

description: Die Entscheidung des Menschenrechtsausschusses der Vereinten Nationen im Fall Billy et al. gegen Australien zum Schutz der Beschwerdeführenden vor den Folgen des Klimawandels wurde als bedeutsamer Erfolg gefeiert. Der Ausschuss bewertet allerdings nur die Adaptationsmaßnahmen Australiens als unzureichend. Der Artikel untersucht, ob die Entscheidung einen Beitrag zur Weiterentwicklung des Klimaschutz- und Klimaanpassungsrechts auf Menschenrechtsebene leistet. Eine nähere Analyse der Entscheidungsgründe zeigt, dass sie weniger progressiv sind als teilweise angenommen. Dennoch stellt die Entscheidung einen Präzedenzfall dar, der angesichts der zunehmenden Bedeutung der Klimaanpassung, auch für nationale Gerichte und regionale Menschenrechtsgerichtshöfe wegweisend ist.
description: The decision of the UN Human Rights Committee in the case of Billy et al. v Australia for the protection of the complainants from the consequences of climate change was celebrated as a significant victory. The Committee, however, only evaluated Australia's adaptation measures as insufficient. The article examines whether the decision contributes to the further development of climate protection and adaptation law on a human rights level. A closer analysis of the case demonstrates that findings by the Committee are less progressive than sometimes assumed. Nevertheless, the decision constitutes a precedent, which, given the increasing importance of climate adaptation, is also important for national courts and regional human rights courts.
Realization of a distributed Bragg reflector for propagating guided matter waves
Creators: name: Fabre, Charlotte M.
name: Cheiney, Pierrick
name: Gattobigio, Giovanni Luca
name: Vermersch, Francois
name: Faure, Stéphane
name: Mathevet, Renaud
name: Lahaye, Thierry
name: Guéry-Odelin, David
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report on the experimental realization of a Bragg reflector for guided matter waves. A Bose-Einstein condensate with controlled velocity distribution impinges onto an attractive optical lattice of finite length and directly probes its band structure. We study the dynamics of the scattering by this potential and compare the results with simple one-dimensional models. We emphasize the importance of taking into account the gaussian envelope of the optical lattice which gives rise to Bragg cavity effects. Our results are a further step towards integrated atom optics setups for quasi-cw matter waves.
description: 4 pages, 5 figures + supplementary material (2 pages, 2 figures)
Deformation and Breakage of Agglomerates: 3D Printing, Experiment and Numerical Analysis
Creators: name: RUIHUAN GE
Publisher: name: Monash University
Year: 2018
Subjects: subject: 90406 Powder and Particle Technology
subject: FOS: Chemical engineering

description: My PhD research project entitled “Creating tuneable agglomerates via 3D printing” is funded by International Fine Particle Research Institute (IFPRI) and Australia ARC Discovery grant. The original objective of this project is to develop a particulate system and experimental methodology to validate particle models. This research has demonstrated, for the first time, how new 3D printing technology can be used to bring “in silico” particles into the physical environment. This method can be widely adopted across the particle modelling community in future and lead to a step change in DEM model sophistication, accuracy and industrial utility.
Androgen receptor modulation by non-androgenic factors and the basal transcription factor TAF1
Creators: name: Tavassoli, Peyman
Publisher: name: University of British Columbia
Year: 2010

description: There is considerable evidence to suggest that progression of prostate cancers to castration-resistant is due to inappropriate activation of the androgen receptor (AR) and hence, the AR is a good target for the treatment of this disease. In this study we used two approaches to investigate AR activation and inhibition. First, we developed high-throughput, non-invasive, cell-based screening assays to rapidly and biologically assess factors that modulate prostate cancer growth and affect AR activity. Using these assays, we found that differentiated osteoblast-like condition media enhanced prostate cancer cell growth, but not AR activity. In addition, we applied this system to screen compounds, selected through in silico approaches against a crucial pocket on the AR protein. The application of our in silico tools and our cell based screening assay resulted in identification of 17 compounds out of 4 millions that can inhibit AR activity. Importantly, some of these compounds are more potent than bicalutamide, which is one of the most potent antiandrogen drugs currently used to treat patients with metastatic prostate cancer. In the context of AR transcription target genes, the presence of AR coactivators is essential for AR activity. Using the repressed transactivator yeast two-hybrid system, we found that TATA binding protein-associated factor 1 (TAF1) interacted with the AR. In tissue microarrays, TAF1 was shown to steadily increase with duration of neoadjuvant androgen withdrawal and with progression to castration resistance. GST pull-down assays established TAF1/AR interaction and co-immunoprecipitation and ChIP assays revealed colocalization of TAF1 and AR on the prostate specific antigen (PSA) promoter in prostate cancer cells. With respect to modulation of AR activity, while full-length TAF1 showed enhancement of both AR and some generic gene transcriptional activity, selective AR coactivator activity was demonstrated in transactivation experiments using cloned TAF1 N-terminal kinase and ubiquitin-activating/conjugating (E1/E2) domains. In keeping with AR coactivation by the E1/E2 domain, TAF1 was found to greatly increase the cellular amount of poly-ubiquitinated AR. In conclusion, our results indicate that TAF1 is a coactivator of AR and its overexpression could be part of a compensatory mechanism adapted by cancer cells to overcome reduced levels of circulating androgens.
Biotechnological assessment of the ferulic acid esterase for sustainable and renewable processing of lignocellulosic biomass
Creators: name: CAMERON JAMES HUNT
Publisher: name: Monash University
Year: 2018
Subjects: subject: 100301 Biocatalysis and Enzyme Technology
subject: FOS: Industrial biotechnology
subject: Biological Engineering
subject: Biotechnology
subject: 60102 Bioinformatics
subject: FOS: Computer and information sciences

description: Plant wastes from the farming and forestry industries can be used to produce new types of fuels, chemicals, and to make energy. However, these wastes need special processing to break them down and separate out the useful parts. This research looked at using a protein called ferulic acid esterase to help separate the parts out more efficiently. Two new proteins were investigated and found to be useful in this separation, and in the production of speciality chemicals. A new system for sorting this class of proteins was also developed, which gives a better indication of which proteins do which things.
Probing the metal-insulator transition of NdNiO3 by electrostatic doping
Creators: name: Son, Junwoo
name: Jalan, Bharat
name: Kajdos, Adam P.
name: Balents, Leon
name: Allen, S. James
name: Stemmer, Susanne
Publisher: name: arXiv
Year: 2011
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Modulation of the charge carrier density in a Mott material by remote doping from a highly doped conventional band insulator is proposed to test theoretical predictions of band filling control of the Mott metal-insulator transition without introducing lattice distortions or disorder, as is the case for chemical doping. The approach is experimentally tested using ultrathin (2.5 nm) NdNiO3 films that are epitaxially grown on La-doped SrTiO3 films. We show that remote doping systematically changes the charge carrier density in the NdNiO3 film and causes a moderate shift in the metal-insulator transition temperature. These results are discussed in the context of theoretical models of this class of materials exhibiting a metal-insulator transition.
description: The article has been accepted by Applied Physics Letters. After it is published, it will be found at http://apl.aip.org/
The Role of Non-native Interactions in the Folding of Knotted Proteins
Creators: name: Skrbic, T.
name: Micheletti, C.
name: Faccioli, P.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Biomolecules (q-bio.BM)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Stochastic simulations of coarse-grained protein models are used to investigate the propensity to form knots in early stages of protein folding. The study is carried out comparatively for two homologous carbamoyltransferases, a natively-knotted N-acetylornithine carbamoyltransferase (AOTCase) and an unknotted ornithine carbamoyltransferase (OTCase). In addition, two different sets of pairwise amino acid interactions are considered: one promoting exclusively native interactions, and the other additionally including non-native quasi-chemical and electrostatic interactions. With the former model neither protein show a propensity to form knots. With the additional non-native interactions, knotting propensity remains negligible for the natively-unknotted OTCase while for AOTCase it is much enhanced. Analysis of the trajectories suggests that the different entanglement of the two transcarbamylases follows from the tendency of the C-terminal to point away from (for OTCase) or approach and eventually thread (for AOTCase) other regions of partly-folded protein. The analysis of the OTCase/AOTCase pair clarifies that natively-knotted proteins can spontaneously knot during early folding stages and that non-native sequence-dependent interactions are important for promoting and disfavoring early knotting events.
description: Accepted for publication on PLOS Computational Biology
Design of Highly Stretchable Conductors for Next-generation Electronics
Creators: name: YAN WANG
Publisher: name: Monash University
Year: 2018
Subjects: subject: 90403 Chemical Engineering Design
subject: FOS: Chemical engineering

description: This thesis has focused on the development and application of highly stretchable electronic conductors based on two novel intrinsically stretchable materials: ionic liquids and standing enokitake-like gold nanowire arrays. These two materials outperform most state-of-arts stretchable conductors. And we specially demonstrated their applications for highly durable biomedical sensors, intrinsically stretchable supercapacitors, “second-skin” facial expression recognition smart mask, and high performance transparent stretchable energy storage devices.
Localized end states in density modulated quantum wires and rings
Creators: name: Gangadharaiah, Suhas
name: Trifunovic, Luka
name: Loss, Daniel
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study finite quantum wires and rings in the presence of a charge density wave gap induced by a periodic modulation of the chemical potential. We show that the Tamm-Shockley bound states emerging at the ends of the wire are stable against weak disorder and interactions, for discrete open chains and for continuum systems. The low-energy physics can be mapped onto the Jackiw-Rebbi equations describing massive Dirac fermions and bound end states. We treat interactions via the continuum model and show that they increase the charge gap and further localize the end states. In an Aharonov-Bohm ring with weak link, the bound states give rise to an unusual $4π$-peridodicity in the spectrum and persistent current as function of an external flux. The electrons placed in the two localized states on the opposite ends of the wire can interact via exchange interactions and this setup can be used as a double quantum dot hosting spin-qubits.
description: 5 pages, 4 figures
Curse of dimensionality reduction in max-plus based approximation methods: theoretical estimates and improved pruning algorithms
Creators: name: Gaubert, Stephane
name: McEneaney, William
name: Qu, Zheng
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optimization and Control (math.OC)
subject: Systems and Control (eess.SY)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Max-plus based methods have been recently developed to approximate the value function of possibly high dimensional optimal control problems. A critical step of these methods consists in approximating a function by a supremum of a small number of functions (max-plus "basis functions") taken from a prescribed dictionary. We study several variants of this approximation problem, which we show to be continuous versions of the facility location and $k$-center combinatorial optimization problems, in which the connection costs arise from a Bregman distance. We give theoretical error estimates, quantifying the number of basis functions needed to reach a prescribed accuracy. We derive from our approach a refinement of the curse of dimensionality free method introduced previously by McEneaney, with a higher accuracy for a comparable computational cost.
description: 8pages 5 figures
Numerical investigation of particle size segregation in piling, hopper filling and discharging processes
Creators: name: TENGFANG ZHANG
Publisher: name: Monash University
Year: 2018
Subjects: subject: 90406 Powder and Particle Technology
subject: FOS: Chemical engineering
subject: 80110 Simulation and Modelling
subject: FOS: Computer and information sciences

description: This thesis examines the size segregation phenomenon in the piling, hopper filling and discharging processes, and the application in a paul-wurth hopper by discrete element method. It clarifies the underlying mechanisms of segregation by the microscopic parameters, including velocity, porosity and forces obtained from the simulation. These four processes are analysed comprehensively. The effects of material property, moisture content, size ratio and volume fraction are investigated. At last, several correlations are proposed to reveal the structural characteristics.
Entrained Flow Gasification of Victorian Brown Coals using CO2 as Reactant
Creators: name: TAO XU
Publisher: name: Monash University
Year: 2018
Subjects: subject: 30602 Chemical Thermodynamics and Energetics
subject: FOS: Chemical sciences
subject: 90499 Chemical Engineering not elsewhere classified
subject: FOS: Chemical engineering
subject: 91305 Energy Generation, Conversion and Storage Engineering
subject: FOS: Mechanical engineering

description: Victoria has abundant brown coal resource, but they are mainly used for mine-mouth power generation units with very low efficiency and high greenhouse gas emissions. Entrained flow gasification is a technology with great potential for Victorian brown coal utilization to produce high-value products. However, little is known about entrained flow gasification of Victorian brown coal. Therefore, the major objective of this study is to obtain a better understanding of entrained flow gasification of Victorian brown coal with CO2 using different experimental and modelling approaches. The focus of this research is to examine: 1) the effect of a wide range of operational variables on gasification performance and emission of air pollutants, 2) the mineral transformation during coal pyrolysis and char gasification, 3) a comparison of entrained flow gasification behaviour of Victorian brown coal and biomass, 4) the kinetic modelling of char-CO2 gasification of Victorian brown coal.
Kelvin-Helmholtz instability in partially ionized compressible plasmas
Creators: name: Soler, R.
name: Diaz, A. J.
name: Ballester, J. L.
name: Goossens, M.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The Kelvin-Helmholtz Instability (KHI) has been observed in the solar atmosphere. Ion-neutral collisions may play a relevant role for the growth rate and evolution of the KHI in solar partially ionized plasmas as in, e.g., solar prominences. Here, we investigate the linear phase of the KHI at an interface between two partially ionized magnetized plasmas in the presence of a shear flow. The effects of ion-neutral collisions and compressibility are included in the analysis. We obtain the dispersion relation of the linear modes and perform parametric studies of the unstable solutions. We find that in the incompressible case the KHI is present for any velocity shear regardless the value of the collision frequency. In the compressible case, the domain of instability depends strongly on the plasma parameters, specially the collision frequency and the density contrast. For high collision frequencies and low density contrasts the KHI is present for super-Alfvenic velocity shear only. For high density contrasts the threshold velocity shear can be reduced to sub-Alfvenic values. For the particular case of turbulent plumes in prominences, we conclude that sub-Alfvenic flow velocities can trigger the KHI thanks to the ion-neutral coupling.
description: Accepted for publication in ApJ
Metal Organic Framework Molecular Sieving Membranes for Energy-efficient Gas Separation
Creators: name: YAOXIN HU
Publisher: name: Monash University
Year: 2020
Subjects: subject: 30301 Chemical Characterisation of Materials
subject: FOS: Chemical sciences

description: Molecular sieving metal organic frameworks (MOFs) membranes offer great potential for gas separation in terms of their low energy consumption. This thesis aims to develop novel and facile methods to fabricate high performance MOF membranes for energy efficient gas separation. Membranes constructed from two dimensional (2D) layered MOFs can be ultrathin, thus enabling the minimization of transport resistance, whilst, maximizing permeability. This thesis demonstrates the synthesis of novel 2D materials/MOF hybrid nanosheets successfully. Utilizing these 2D hybrid nanosheets as building blocks, facile and advanced fabrication strategies were developed for ultrathin molecular sieving MOF-based membranes.
Modified Chaplygin Gas as a Unified Dark Matter and Dark Energy Model and Cosmic Constraints
Creators: name: Xu, Lixin
name: Wang, Yuting
name: Noh, Hyerim
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: A modified Chaplygin gas model (MCG), $ρ_{MCG}/ρ_{MCG0}=[B_{s}+(1-B_{s})a^{-3(1+B)(1+α)}]^{1/(1+α)}$, as a unified dark matter model and dark energy model is constrained by using current available cosmic observational data points which include type Ia supernovae, baryon acoustic oscillation and the seventh year full WMAP data points. As a contrast to the consideration in the literatures, we {\it do not} separate the MCG into two components, i.e. dark mater and dark energy component, but we take it as a whole energy component-a unified dark sector. By using Markov Chain Monte Carlo method, a tight constraint is obtained: $α= 0.000727_{- 0.00140- 0.00234}^{+ 0.00142+ 0.00391}$, $B=0.000777_{- 0.000302- 0.000697}^{+ 0.000201+ 0.000915}$ and $B_s= 0.782_{- 0.0162- 0.0329}^{+ 0.0163+ 0.0307}$ .}
description: 6 pages, 3 figures
Oil/water separation by Nano Cellulose Aerogel Sponge Filter
Creators: name: ZHIYONG HE
Publisher: name: Monash University
Year: 2017
Subjects: subject: 30301 Chemical Characterisation of Materials
subject: FOS: Chemical sciences
subject: Environmental Chemistry

description: A nano-cellulose aerogel filter with exhibiting super-hydrophilic and underwater-super-oleophobic behaviours is synthesized by a facile method of cross-linking between cellulose fibres and polyamideamine-epichlorohydrin. The prepared aerogel showed excellent oil/water separation efficiency for both oil/water mixtures and oil/water surfactant-free emulsion, which showed that the cellulose aerogel filter can be used for oil/water separation and recovery. However, the aerogel filter was still faced with difficulties in separating oil/water surfactant-stabilized emulsion due to its relatively large pores within the structure. Therefore, a second layer was coated onto the single layer cellulose aerogel in order to achieve improved performance in separating oil/water stabilized emulsion.
Sunspot rotation, filament, and flare: The event on 2000 February 10
Creators: name: Yan, X. L.
name: Qu, Z. Q.
name: Kong, D. F.
name: Xu, C. L.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We find that a sunspot with positive polarity had an obvious counter-clockwise rotation and resulted in the formation and eruption of an inverse S-shaped filament in NOAA active region (AR) 08858 from 2000 February 9 to 10. The sunspot had two umbrae which rotated around each other by 195 degrees within about twenty-four hours. The average rotation rate was nearly 8 degrees per hour. The fastest rotation in the photosphere took place during 14:00UT to 22:01UT on February 9, with the rotation rate of nearly 16 degrees per hour. The fastest rotation in the chromosphere and the corona took place during 15:28UT to 19:00UT on February 9, with the rotation rate of nearly 20 degrees per hour. Interestingly, the rapid increase of the positive magnetic flux just occurred during the fastest rotation of the rotating sunspot, the bright loop-shaped structure and the filament. During the sunspot rotation, the inverse S-shaped filament gradually formed in the EUV filament channel. The filament experienced two eruptions. In the first eruption, the filament rose quickly and then the filament loops carrying the cool and the hot material were seen to spiral into the sunspot counterclockwise. About ten minutes later, the filament became active and finally erupted. The filament eruption was accompanied with a C-class flare and a halo coronal mass ejection (CME). These results provide evidence that sunspot rotation plays an important role in the formation and eruption of the sigmoidal active-region filament.
description: 20 pages, 9 figures, Accepted for publication in ApJ
The set-theoretic multiverse
Creators: name: Hamkins, Joel David
Publisher: name: arXiv
Year: 2011
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03Axx, 03Exx

description: The multiverse view in set theory, introduced and argued for in this article, is the view that there are many distinct concepts of set, each instantiated in a corresponding set-theoretic universe. The universe view, in contrast, asserts that there is an absolute background set concept, with a corresponding absolute set-theoretic universe in which every set-theoretic question has a definite answer. The multiverse position, I argue, explains our experience with the enormous diversity of set-theoretic possibilities, a phenomenon that challenges the universe view. In particular, I argue that the continuum hypothesis is settled on the multiverse view by our extensive knowledge about how it behaves in the multiverse, and as a result it can no longer be settled in the manner formerly hoped for.
description: 35 pages
Synthesis of NiO-Nanoparticles Templated on Chitosan Biopolymer for Photocatalytic Degradation of Methylene Blue Dye
Creators: name: CHENG KEONG CHOO
Publisher: name: Monash University
Year: 2017
Subjects: subject: 30306 Synthesis of Materials
subject: FOS: Chemical sciences
subject: 30601 Catalysis and Mechanisms of Reactions
subject: 91207 Metals and Alloy Materials
subject: FOS: Materials engineering

description: In this study, nickel oxide nanoparticle is produced by two different synthesis techniques, namely extrusion-dripping/sol-gel and hydrothermal processing using chitosan biopolymer as templating material. The properties of synthesized nanoparticles were examined through various characterisation techniques. Furthermore, the catalytic performance of both materials were compared based on the photocatalytic degradation of methylene blue dye.
Strong coupling between mechanical modes in a nanotube resonator
Creators: name: Eichler, A.
name: Ruiz, M. del Álamo
name: Plaza, J. A.
name: Bachtold, A.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We report on the nonlinear coupling between the mechanical modes of a nanotube resonator. The coupling is revealed in a pump-probe experiment where a mode driven by a pump force is shown to modify the motion of a second mode measured with a probe force. In a second series of experiments, we actuate the resonator with only one oscillating force. Mechanical resonances feature exotic lineshapes with reproducible dips, peaks, and jumps when the measured mode is commensurate with another mode with a frequency ratio of either 2 or 3. Conventional lineshapes are recovered by detuning the frequency ratio using the voltage on a nearby gate electrode. The exotic lineshapes are attributed to strong coupling between the mechanical modes. The possibility to control the strength of the coupling with the gate voltage holds promise for various experiments, such as quantum manipulation, mechanical signal processing, and the study of the quantum-toclassical transition.
description: manuscript and supporting material, 31 pages, 15 figures
Synthesis and Transport Mechanism of Reduced Graphene Oxide Membranes for Water Processing
Creators: name: HUIYUAN LIU
Publisher: name: Monash University
Year: 2020
Subjects: subject: 100708 Nanomaterials
subject: FOS: Nanotechnology

description: In this thesis, a facile and efficient method has been developed to fabricate ultrathin freestanding rGO membranes for forward osmosis process. The rGO membranes achieve 3-4 times higher water flux than commercial FO membranes. In addition, the rGO membranes exhibit improved stability in aqueous solutions and have a high rejection of both organic and inorganic species. Further investigation into the mass transport mechanism in these membranes reveals that nanowrinkles are the fast channels for water molecules, while the inter-edge gaps are essential for the selective transport of water over salts in rGO membranes.
Engineering adhesive proteins enhanced by self-assembling peptide and enzyme cross-linking
Creators: name: JAMIE JOSEPH CASTILLO
Publisher: name: Monash University
Year: 2017
Subjects: Biological Engineering
Biotechnology

description: Conventional adhesives efficiently work on dry surfaces but fail in the presence of water. Currently, there is a great need for adhesives in surgical procedures and underwater construction. Nature gives a hint on how to develop wet adhesives. Mussels survive harsh underwater conditions by secreting an adhesive which attaches to different surfaces. However, natural extraction was found uneconomical. Recombinant engineering approach is a promising alternative method for large-scale adhesive production. Unfortunately, recombinant adhesives face drawbacks such as low performance. This thesis aims to address these drawbacks by designing and synthesising recombinant adhesives, developing a bioproduction, and evaluating their performance.
Optical and Luminescence Properties of Zinc Oxide
Creators: name: Rodnyi, P. A.
name: Khodyuk, I. V.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Nuclear Experiment (nucl-ex)
subject: Instrumentation and Detectors (physics.ins-det)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We generalize and systematize basic experimental data on optical and luminescence properties of ZnO single crystals, thin films, powders, ceramics, and nanocrystals. We consider and study mechanisms by which two main emission bands occur, a short-wavelength band near the fundamental absorption edge and a broad long-wavelength band, the maximum of which usually lies in the green spectral range. We determine a relationship between the two luminescence bands and study in detail the possibility of controlling the characteristics of ZnO by varying the maximum position of the short-wavelength band. We show that the optical and luminescence characteristics of ZnO largely depend on the choice of the corresponding impurity and the parameters of the synthesis and subsequent treatment of the sample. Prospects for using zinc oxide as a scintillator material are discussed. Additionally, we consider experimental results that are of principal interest for practice.
description: 15 pages, 7 figures, review article
Energy dependence of the dijet imbalance in Pb-Pb collisions at 2.76 ATeV
Creators: name: Renk, Thorsten
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The appearance of monojets is among the most striking signature of jet quenching in the context of ultrarelativistic heavy-ion collisions at the Large Hadron Collider. Experimentally, the asymmetry of back-to-back jets is quantified in terms of the dijet imbalance distribution by the ATLAS and CMS collaborations. Recently, the CMS collaboration has also studied the trigger jet momentum (P_T) dependence of the imbalance in the range between 120 and 500 GeV which is found to decrease with jet P_T. In this work, results from the in-medium shower code YaJEM are compared with this data set. These results suggest that the main effects observed in the data are the kinematical collimation of jets and the increase in the probability to produce more collimated quark jets with jet P_T, whereas there is no indication for any non-trivial energy dependence of the shower-medium interaction mechanism itself. The data furthermore can rule out models in which the jet shape is collimated due to the medium modification.
description: 4 pages, 1 figure
A Counterexample to rapid mixing of the Ge-Stefankovic Process
Creators: name: Goldberg, Leslie Ann
name: Jerrum, Mark
Publisher: name: arXiv
Year: 2011
Subjects: subject: Probability (math.PR)
subject: Data Structures and Algorithms (cs.DS)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 60J10 60C05 68W20 05C69 05C31

description: Ge and Stefankovic have recently introduced a novel two-variable graph polynomial. When specialised to a bipartite graphs G and evaluated at the point (1/2,1) this polynomial gives the number of independent sets in the graph. Inspired by this polynomial, they also introduced a Markov chain which, if rapidly mixing, would provide an efficient sampling procedure for independent sets in G. This sampling procedure in turn would imply the existence of efficient approximation algorithms for a number of significant counting problems whose complexity is so far unresolved. The proposed Markov chain is promising, in the sense that it overcomes the most obvious barrier to mixing. However, we show here, by exhibiting a sequence of counterexamples, that the mixing time of their Markov chain is exponential in the size of the input when the input is chosen from a particular infinite family of bipartite graphs.
O PROGRAMA DE EDUCAÇÃO TUTORIAL DE CIÊNCIA DA COMPUTAÇÃO DA UNIVERSIDADE FEDERAL DA PARAÍBA
Creators: name: LEONARDO VIDAL BATISTA, ufpb
Publisher: name: Zenodo
Year: 2023
Subjects: : programa de educação tutorial
ciência da computação

description: Este livro resume a história do PET de Ciência da Computação da UFPB, organizando, apresentando e analisando uma gama de dados que caracterizam os desdobramentos acadêmicos e sociais, a inserção dos egressos na pós-graduação e no mercado de trabalho, e os efeitos da participação no Programa sobre os próprios integrantes. O estudo compreende toda a história do PET Computação da UFPB, desde sua criação em 2006 até os primeiros meses de 2022
Adsorption of hard spheres: structure and effective density according to the potential distribution theorem
Creators: name: Lee, L. L.
name: Pellicane, G.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We propose a new type of effective densities via the potential distribution theorem. These densities are for the sake of enabling the mapping of the free energy of a uniform fluid onto that of a nonuniform fluid. The potential distribution theorem gives the work required to insert a test particle into the bath molecules under the action of the external (wall) potential. This insertion work W_ins can be obtained from Monte Carlo (MC) simulation (e.g. from Widom's test particle technique) or from an analytical theory. The pseudo-densities are constructed thusly so that when their values are substituted into a uniform-fluid equation of state (e.g. the Carnahan-Starling equation for the hard-sphere chemical potentials), the MC nonuniform insertion work is reproduced. We characterize the pseudo-density behavior for the hard spheres/hard wall system at moderate to high densities (from ρ^*= 0.5745 to 0.9135). We adopt the MC data of Groot et al. for this purpose. The pseudo-densities show oscillatory behavior out of phase (opposite) to that of the singlet densities. We also construct a new closure-based density functional theory (the star-function based density functional theory) that can give accurate description of the MC density profiles and insertion works. A viable theory is established for several cases in hard sphere adsorption.
description: 15 pages, 10 figures
Superfluid behaviour of a two-dimensional Bose gas
Creators: name: Desbuquois, Rémi
name: Chomaz, Lauriane
name: Yefsah, Tarik
name: Léonard, Julian
name: Beugnon, Jérôme
name: Weitenberg, Christof
name: Dalibard, Jean
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Two-dimensional (2D) systems play a special role in many-body physics. Because of thermal fluctuations, they cannot undergo a conventional phase transition associated to the breaking of a continuous symmetry. Nevertheless they may exhibit a phase transition to a state with quasi-long range order via the Berezinskii-Kosterlitz-Thouless (BKT) mechanism. A paradigm example is the 2D Bose fluid, such as a liquid helium film, which cannot Bose-condense at non-zero temperature although it becomes superfluid above a critical phase space density. Ultracold atomic gases constitute versatile systems in which the 2D quasi-long range coherence and the microscopic nature of the BKT transition were recently explored. However, a direct observation of superfluidity in terms of frictionless flow is still missing for these systems. Here we probe the superfluidity of a 2D trapped Bose gas with a moving obstacle formed by a micron-sized laser beam. We find a dramatic variation of the response of the fluid, depending on its degree of degeneracy at the obstacle location. In particular we do not observe any significant heating in the central, highly degenerate region if the velocity of the obstacle is below a critical value.
description: 5 pages, 3 figures
Photon-induced carrier transport in high efficiency midinfrared quantum cascade lasers
Creators: name: Mátyás, Alpár
name: Lugli, Paolo
name: Jirauschek, Christian
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Computational Physics (physics.comp-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: A midinfrared quantum cascade laser with high wall-plug efficiency is analyzed by means of an ensemble Monte Carlo method. Both the carrier transport and the cavity field dynamics are included in the simulation, offering a self-consistent approach for analyzing and optimizing the laser operation. It is shown that at low temperatures, photon emission and absorption can govern the carrier transport in such devices. Furthermore, we find that photon-induced scattering can strongly affect the kinetic electron distributions within the subbands. Our results are validated against available experimental data.
On intersections of closed curves on surfaces
Creators: name: Bogatyi, Semeon A.
name: Kudryavtseva, Elena A.
name: Zieschang, Heiner
Publisher: name: arXiv
Year: 2011
Subjects: subject: Algebraic Topology (math.AT)
subject: Differential Geometry (math.DG)
subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 54H25, 55M20, 55N33, 55N45, 57N05, 57N35, 57M10, 57M50

description: The problem on the minimal number (with respect to deformation) of intersection points of two closed curves on a surface is solved. Following the Nielsen approach, we define classes of intersection points and essential classes of intersection points, which "are preserved under deformation" and whose total number is called the Nielsen number. If each Nielsen class consists of a unique point and has a non-vanishing index after a suitable deformation of the pair of curves, one says that {\it the Wecken property holds}. We compute the minimal number of intersection points in terms of the Nielsen numbers and the Reidemeister numbers. In particular, we prove that the Wecken property does not hold for some pairs of closed curves. Moreover, all the non-vanishing indices of the Nielsen classes equal $\pm1$, while the non-vanishing Jezierski semi-indices equal 1. Similar questions are studied for the self-intersection problem of a curve on a surface.
description: 36 pages, 4 figures, in Russian
A Second-order bias model for the Logarithmic Halo Mass Density
Creators: name: Jee, Inh
name: Park, Changbom
name: Kim, Juhan
name: Choi, Yun-Young
name: Kim, Sungsoo S.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present an analytic model for the local bias of dark matter halos in a LCDM universe. The model uses the halo mass density instead of the halo number density and is searched for various halo mass cuts, smoothing lengths, and redshift epoches. We find that, when the logarithmic density is used, the second-order polynomial can fit the numerical relation between the halo mass distribution and the underlying matter distribution extremely well. In this model the logarithm of the dark matter density is expanded in terms of log halo mass density to the second order. The model remains excellent for all halo mass cuts (from M_{cut}=3\times10^{11}$ to $3\times10^{12}h^{-1}M_{\odot}$), smoothing scales (from $R=5h^{-1}$Mpc to $50h^{-1}$Mpc), and redshift ranges (from z=0 to 1.0) considered in this study. The stochastic term in the relation is found not entirely random, but a part of the term can be determined by the magnitude of the shear tensor.
description: 8 pages, 7 figures, accepted for publication on ApJ