bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental investigation of fiber reinforced composite leaf springs
Authors: Koçhan Cemal , Belevi Melih 
Published: October 2017

Abstract
The aim of this study is to experimentally investigate fiber reinforced polymeric composite leaf springs which could be used in a light commercial vehicle instead of a double steel leaf spring. E-glass/epoxy, carbon/epoxy and E-glass-carbon/epoxy flat leaf springs were produced by vacuum assisted resin transfer molding (VARTM) method with specially designed mold. Experimental results show that spring rates were 91.4, 98.4 and 97.1 N × mm−1 for carbon/epoxy, E-glass/epoxy and E-glass-carbon/epoxy leaf springs, respectively. Fatigue tests indicate that the carbon/epoxy leaf springs have the longest average usage life with approximately 89 % weight reduction, although E-glass/epoxy ones satisfy the minimum usage life requirements with higher load carrying capacity with 82 % weight reduction.
Comparison of three methods for determining Vickers hardness by instrumented indentation testing
Authors: Wang Jialiang 
Published: October 2017

Abstract
To address the problem of poor accuracy associated with using instrumented indentation tests to determine Vickers hardness, and the problem of selection of the most appropriate instrumented indentation approach, the finite element method was adopted to determine theoretical Vickers hardness values of different materials. On the basis of these theoretical values, a theoretical accuracy analysis of three representative methods was conducted for determining Vickers hardness via instrumented indentation: ISO method, Kang method and Ma method. Moreover, the results of the analysis were experimentally verified. The results show that with increasing ratio between the unloading work We and total unloading work Wt (i. e., We/Wt), the theoretical error of Vickers hardness determined using each of the investigated instrumented indentation methods initially decreases and then increases. Compared to the other two instrumented indentation methods, the Ma method gave the lowest theoretical error of Vickers hardness. When the We/Wt ratio ranged from 0.01 to 0.3, with different values of the plane strain elastic modulus ratio η and strain-hardening ratio n, the errors of Vickers hardness determined using each of the investigated methods were all discrete. By contrast, when We/Wt ranged from 0.3 to 0.81, the errors were relatively concentrated. This work provides a theoretical basis for the further study of new methods for determining Vickers hardness via instrumented indentation testing.
Application of a clay-slag geopolymer matrix for repairing damaged concrete: Laboratory and industrial-scale experiments
Authors: Perná Ivana , Hanzlíček Tomáš , Boura Patrik , Lučaník Adam 
Published: October 2017

Abstract
Blast-furnace slag, a remnant of the old iron production, was used for a preparation of a clay-slag geopolymer which was applied to old concrete surface. An interface investigation by scan electron microscopy (SEM) confirmed the hypothesis that a clay-slag geopolymer can be used for repairing concrete. Based on the laboratory experiments, a highly damaged and contaminated old concrete floor with potholes ranging from 2 mm to 20 cm, located in metal manufacturing industrial plant, has been repaired overnight by a clay-slag geopolymer matrix (ratio of 1 : 0.5) filled with sand and pebbles (the total content of 70 wt.-%). This industrial-scale experiment has proven that geopolymers are suitable for damaged concrete repair and the daily rush in heavy industrial conditions has confirmed the resistance and surface hardness of the geopolymer mixture used. The article documents the original state of the floor, its state after eight hours and also two and four years later.
Characterization of adhesively bonded high strength steel surfaces treated with grit blasting and self-indicating pretreatment (SIP) adhesion mediator
Authors: Anagreh Nabil , Dweiri Radwan , Masadeh Sami 
Published: October 2017

Abstract
This work aimed at investigating the adhesion behavior of high strength steels (dual phase steel of grade DP 600 and microalloyed steel of grade ZStE340) which were glued with epoxy and polyurethane adhesives. To improve the adhesion strength of the steel surfaces, the surfaces were treated with three different methods: grit blasting with corundum or duroplast, self-indicating pretreatment (SIP) adhesion mediator, or a combination of grit blasting and SIP. The samples were aged in hot climate for 25 days. SEM investigations showed that the surface roughness values were significantly increased after grit blasting. Using EDX analysis, the surface of DP 600 steel after grit blasting indicated that the zinc concentration on the surface was clearly decreased, obviously in case of duroplast blasting. Whereas, the surface of ZStE340 steel after grit blasting showed that the carbon concentration was decreased. Adhesion strength of the samples in their fresh condition is dependent on adhesive type, steel grade and pretreatment method. SIP treatment was found to have a positive impact on the adhesion strength of the DP 600 steel regardless the type of adhesive. The effect of grit blasting on adhesion strength was more pronounced in case of ZStE340 steel. Generally, the adhesion strength of the aged DP 600 or ZStE340 samples was slightly decreased, with some exceptions confined to ZStE340 glued with EP 3 which showed an increase in the aging strength. The fracture surfaces of all samples were also examined in this work by naked eye and SEM.
Phase formation in alloy-type anode materials in the quaternary system Li–Sn–Si–C
Authors: Drüe Martin , Liang Song-Mao , Seyring Martin , Kozlov Artem , Song Xiaoyan , Rettenmayr Markus , Schmid-Fetzer Rainer 
Published: October 2017

AbstractInvestigations on the thermodynamics of alloy-type anode materials have been carried out for the quaternary Li–C–Si–Sn system. Phase equilibria and phase stabilities were characterized in the binary subsystems Li–C, Li–Si, Li–Sn. The Calphad method was first used to optimize or completely re-establish all binary subsystems containing Li. For reasons of consistency, the binary subsystem Si–C had to be revisited and its Calphad description was modified. The ternary phase diagrams were then tentatively calculated by extrapolation from the binary subsystems and confirmed by key experiments. No ternary compounds were found. In order to verify the applicability of the anode materials in real batteries, some of the materials were nanostructured by ball milling and spark plasma sintering, the corresponding nanostructures were characterized. Theoretical predictions that nanograined Li2C2 can also be used as cathode material were verified experimentally. The methodologies worked out in the present project (e. g. nanoscale structure transmission electron microscopy analysis, glow discharge optical emission spectroscopy) were also employed in other projects and led to publications concerning other materials such as Mg alloys, carbon nanofibers and an Mn-based antiperovskite.
Effect of flow, heat transfer and magnetic energy on the grain refinement of 7A04 alloy under electromagnetic pulse
Authors: Bai Qingwei , Ma Yonglin , Xing Shuqing , Bao Xinyu , Feng Yanfei , Yu Wenxia , Kang Xiaolan 
Published: October 2017

Abstract
In this paper, a transient numerical simulation method was used to analyze the direct chill casting process of 7A04 alloy under electromagnetic pulse treatment. The distribution and evolution of the electromagnetic force, fluid and thermal fields were studied to determine their effect on the solidification characteristics of alloy ingots. A modified nucleation theory for the refinement of grain size was presented considering the effect of electromagnetic energy on the critical Gibbs free energy

Δ

G
*

$\Delta {G^*}$

of the unity, which was verified by the corresponding experiments. The results showed that the swirl rings of the axial section in the melt were restrained and a lower temperature gradient was formed in the radial section when the magnetic flux intensity was increased. Under these conditions for nucleation, the grain refinement could be explained by the electromagnetic pulse energy that reduced the energy barrier and improved the nucleation rate, either heterogeneous nucleation or homogeneous nucleation.
Evidence for Galaxy Dynamics Tracing Background Cosmology Below the de Sitter Scale of Acceleration
Authors: van Putten Maurice H. P. M. 
Published: October 2017

Abstract
Galaxy dynamics probe weak gravity at accelerations below the de Sitter scale of acceleration

, where c is the velocity of light and H is the Hubble parameter. Low- and high-redshift galaxies hereby offer a novel probe of weak gravity in an evolving cosmology, satisfying

/

with matter content

sans tension to H
0 in surveys of the local universe. Galaxy rotation curves show anomalous galaxy dynamics in weak gravity

across a transition radius

in galaxies of mass

, where a

N
is the Newtonian acceleration based on baryonic matter content. We identify this behavior with a holographic origin of inertia from entanglement entropy, which introduces a C
0 onset across

with asymptotic behavior described by a Milgrom parameter satisfying

, where

is a fundamental eigenfrequency of the cosmological horizon. Extending an earlier confrontation with data covering

at redshift

in Lellie et al., the modest anomalous behavior in the Genzel et al. sample at redshifts

is found to be mostly due to clustering

close to the C
0 onset to weak gravity and an increase of up to 65% in a
0.
Uplift, Feedback, and Buoyancy: Radio Lobe Dynamics in NGC 4472
Authors: Gendron-Marsolais M. , Kraft R. P. , Bogdan A. , Hlavacek-Larrondo J. , Forman W. R. , Jones C. , Su Y. , Nulsen P. , Randall S. W. , Roediger E. 
Published: October 2017

Abstract
We present results from deep (380 ks) Chandra observations of the active galactic nucleus (AGN) outburst in the massive early-type galaxy NGC 4472. We detect cavities in the gas coincident with the radio lobes and estimate the eastern and western lobe enthalpy to be

erg and

erg and the average power required to inflate the lobes to be

erg s−1 and

erg s−1, respectively. We also detect enhanced X-ray rims around the radio lobes with sharp surface brightness discontinuities between the shells and the ambient gas. The temperature of the gas in the shells is less than that of the ambient medium, suggesting that they are not AGN-driven shocks but rather gas uplifted from the core by the buoyant rise of the radio bubbles. We estimate the energy required to lift the gas to be up to

erg and

erg for the eastern and western rims, respectively, constituting a significant fraction of the total outburst energy. A more conservative estimate suggests that the gas in the rim was uplifted at a smaller distance, requiring only 20%–25% of this energy. In either case, if a significant fraction of this uplift energy is thermalized via hydrodynamic instabilities or thermal conduction, our results suggest that it could be an important source of heating in cool core clusters and groups. We also find evidence for a central abundance drop in NGC 4472. The iron abundance profile shows that the region along the cavity system has a lower metallicity than the surrounding undisturbed gas, similar to the central region. This also shows that bubbles have lifted low-metallicity gas from the center.
A Three-dimensional Magnetohydrodynamic Simulation of the Formation of Solar Chromospheric Jets with Twisted Magnetic Field Lines
Authors: Iijima H. , Yokoyama T. 
Published: October 2017

Abstract
This paper presents a three-dimensional simulation of chromospheric jets with twisted magnetic field lines. Detailed treatments of the photospheric radiative transfer and the equations of state allow us to model realistic thermal convection near the solar surface, which excites various MHD waves and produces chromospheric jets in the simulation. A tall chromospheric jet with a maximum height of 10–11 Mm and lifetime of 8–10 minutes is formed above a strong magnetic field concentration. The magnetic field lines are strongly entangled in the chromosphere, which helps the chromospheric jet to be driven by the Lorentz force. The jet exhibits oscillatory motion as a natural consequence of its generation mechanism. We also find that the produced chromospheric jet forms a cluster with a diameter of several Mm with finer strands. These results imply a close relationship between the simulated jet and solar spicules.
The Three-part Structure of a Filament-unrelated Solar Coronal Mass Ejection
Authors: Song H. Q. , Cheng X. , Chen Y. , Zhang J. , Wang B. , Li L. P. , Li B. , Hu Q. , Li G. 
Published: October 2017

Abstract
Coronal mass ejections (CMEs) often exhibit the typical three-part structure in the corona when observed with white-light coronagraphs, i.e., the bright leading front, dark cavity, and bright core, corresponding to a high-low-high density sequence. As CMEs result from eruptions of magnetic flux ropes (MFRs), which can possess either lower (e.g., coronal-cavity MFRs) or higher (e.g., hot-channel MFRs) density compared to their surroundings in the corona, the traditional opinion regards the three-part structure as the manifestations of coronal plasma pileup (high density), coronal-cavity MFR (low density), and filament (high density) contained in the trailing part of MFR, respectively. In this paper, we demonstrate that filament-unrelated CMEs can also exhibit the classical three-part structure. The observations were made from different perspectives through an event that occurred on 2011 October 4. The CME cavity corresponds to the low-density zone between the leading front and the high-density core, and it is obvious in the low corona and gradually becomes fuzzy when propagating outward. The bright core corresponds to a high-density structure that is suggested to be an erupting MFR. The MFR is recorded from both edge-on and face-on perspectives, exhibiting different morphologies that are due to projection effects. We stress that the zone (MFR) with lower (higher) density in comparison to the surroundings can appear as the dark cavity (bright core) when observed through white-light coronagraphs, which is not necessarily the coronal-cavity MFR (erupted filament).
White Dwarf Rotation as a Function of Mass and a Dichotomy of Mode Line Widths: Kepler Observations of 27 Pulsating DA White Dwarfs through K2 Campaign 8
Authors: Hermes J. J. , Gänsicke B. T. , Kawaler Steven D. , Greiss S. , Tremblay P.-E. , Fusillo N. P. Gentile , Raddi R. , Fanale S. M. , Bell Keaton J. , Dennihy E. , Fuchs J. T. , Dunlap B. H. , Clemens J. C. , Montgomery M. H. , Winget D. E. , Chote P. , Marsh T. R. , Redfield S. 
Published: October 2017

Abstract
We present photometry and spectroscopy for 27 pulsating hydrogen-atmosphere white dwarfs (DAVs; a.k.a. ZZ Ceti stars) observed by the Kepler space telescope up to K2 Campaign 8, an extensive compilation of observations with unprecedented duration (>75 days) and duty cycle (>90%). The space-based photometry reveals pulsation properties previously inaccessible to ground-based observations. We observe a sharp dichotomy in oscillation mode line widths at roughly 800 s, such that white dwarf pulsations with periods exceeding 800 s have substantially broader mode line widths, more reminiscent of a damped harmonic oscillator than a heat-driven pulsator. Extended Kepler coverage also permits extensive mode identification: we identify the spherical degree of 87 out of 201 unique radial orders, providing direct constraints of the rotation period for 20 of these 27 DAVs, more than doubling the number of white dwarfs with rotation periods determined via asteroseismology. We also obtain spectroscopy from 4 m-class telescopes for all DAVs with Kepler photometry. Using these homogeneously analyzed spectra, we estimate the overall mass of all 27 DAVs, which allows us to measure white dwarf rotation as a function of mass, constraining the endpoints of angular momentum in low- and intermediate-mass stars. We find that 0.51–0.73 M
⊙ white dwarfs, which evolved from 1.7–3.0 M
⊙ ZAMS progenitors, have a mean rotation period of 35 hr with a standard deviation of 28 hr, with notable exceptions for higher-mass white dwarfs. Finally, we announce an online repository for our Kepler data and follow-up spectroscopy, which we collect at http://k2wd.org.
First Characterization of the Neutral ISM in Two Local Volume Dwarf Galaxies
Authors: Bralts-Kelly Lilly , Bulatek Alyssa M. , Chinski Sarah , Ford Robert N. , Gilbonio Hannah E. , Helmel Greta , McGlasson Riley , Mizener Andrew , Cannon John M. , Kaisin Serafim , Karachentsev Igor , Denn Grant 
Published: October 2017

Abstract
We present the first H i spectral-line images of the nearby, star-forming dwarf galaxies UGC 11411 and UGC 8245, acquired as part of the “Observing for University Classes” program with the Karl G. Jansky Very Large Array (VLA). These low-resolution images localize the H i gas and reveal the bulk kinematics of each system. Comparing with Hubble Space Telescope (HST) broadband and ground-based Hα imaging, we find that the ongoing star formation in each galaxy is associated with the highest H i mass surface density regions. UGC 8245 has a much lower current star formation rate than UGC 11411, which harbors very high surface brightness Hα emission in the inner disk and diffuse, lower surface brightness nebular gas that extends well beyond the stellar disk as traced by HST. We measure the dynamical masses of each galaxy and find that the halo of UGC 11411 is more than an order of magnitude more massive than the halo of UGC 8245, even though the H i and stellar masses of the sources are similar. We show that UGC 8245 shares similar physical properties with other well-studied low-mass galaxies, while UGC 11411 is more highly dark matter dominated. Both systems have negative peculiar velocities that are associated with a coherent flow of nearby galaxies at high supergalactic latitude.
Simultaneous Observations of p-mode Light Walls and Magnetic Reconnection Ejections above Sunspot Light Bridges
Authors: Hou Yijun , Zhang Jun , Li Ting , Yang Shuhong , Li Xiaohong 
Published: October 2017

Abstract
Recent high-resolution observations from the Interface Region Imaging Spectrograph reveal bright wall-shaped structures in active regions (ARs), especially above sunspot light bridges. Their most prominent feature is the bright oscillating front in the 1400/1330 Å channel. These structures are named light walls and are often interpreted to be driven by p-mode waves. Above the light bridge of AR 12222 on 2014 December 06, we observed intermittent ejections superimposed on an oscillating light wall in the 1400 Å passband. At the base location of each ejection, the emission enhancement was detected in the Solar Dynamics Observatory 1600 Å channel. Thus, we suggest that in wall bases (light bridges), in addition to the leaked p-mode waves consistently driving the oscillating light wall, magnetic reconnection could happen intermittently at some locations and eject the heated plasma upward. Similarly, in the second event occurring in AR 12371 on 2015 June 16, a jet was simultaneously detected in addition to the light wall with a wave-shaped bright front above the light bridge. At the footpoint of this jet, lasting brightening was observed, implying magnetic reconnection at the base. We propose that in these events, two mechanisms, p-mode waves and magnetic reconnection, simultaneously play roles in the light bridge, and lead to the distinct kinetic features of the light walls and the ejection-like activities, respectively. To illustrate the two mechanisms and their resulting activities above light bridges, in this study we present a cartoon model.
HIV-1 Viral Load and Resistance in Genital Secretions in Patients Taking Protease-Inhibitor-Based Second-Line Therapy in Africa
Authors: Hoppe Anne , Giuliano Marina , Lugemwa Abbas , Thompson Jennifer A , Floridia Marco , Walker Ann S , Senoga Ismail , Abwola Mary C , Pirillo Maria F , Kityo Cissy M , Arenas-Pinto Alejandro , Paton Nicholas I ,   the EARNEST Trial Team
Published: October 2017

Background HIV is transmitted primarily through sexual intercourse, and the objective of this study was therefore to assess whether there is occult viral replication and resistance in genital secretions in patients on protease inhibitor (PI)-based second-line therapy. Methods HIV-infected adults taking ritonavir-boosted lopinavir with either two nucleoside reverse transcriptase inhibitors (NRTIs), raltegravir or as monotherapy for 96 weeks, were enrolled at seven clinical sites in Uganda. Viral load (VL) was measured in cervico-vaginal secretions or semen and in a corresponding plasma sample. Genotypic resistance was assessed in genital secretion samples and plasma samples. Results were compared between compartments and with the plasma resistance profile at first-line failure. Results Of the 111 participants enrolled (91 female, 20 male), 16 (14%) and 30 (27%) had VL >1,000 and >40 copies/ml, respectively, in plasma; 3 (3%) and 23 (21%) had VL >1,000 copies/ml and >40 copies/ml, respectively, in genital secretions. There was 74% agreement between plasma and genital secretion VL classification above/below 40 copies/ml threshold (kappa-statistic =0.29; P=0.001). RT mutations (both NRTI and non-nucleoside reverse transcriptase inhibitor) were detected in genital secretions in four patients (similar profile to corresponding plasma sample at first-line failure) and PI mutations were detected in two (one polymorphism with no impact on resistance; one with high-level PI resistance). Conclusions High level (>1,000 copies/ml) viral replication and development of new RT or PI resistance in the genital compartment were rare. The risks of transmission arising from resistance evolution in the genital compartment are likely to be low on PI-based second-line therapy.
Surgical Outcome of Congenital Cataract in Eyes With Microcornea
Authors: Matalia Jyoti , Shirke Sheetal , Shetty K. Bhujang , Matalia Himanshu 
Published: October 2017

Purpose:
To report the intraoperative and postoperative outcomes of congenital cataract surgery in eyes with microcornea.

Methods:
In this retrospective, interventional, comparative case series, the authors reviewed 47 eyes of 26 children with microcornea and congenital cataract (21 bilateral and 5 unilateral) who underwent lens aspiration with primary posterior capsulectomy and anterior vitrectomy between 2008 and 2014 with a minimum follow-up period of 6 months. Demographic profiles and systemic and ocular features were documented. Intraoperative and postoperative complications were studied separately for bilateral and unilateral cases. Patients were also divided into two groups on the basis of their ages at surgery (early surgery group: 3 months or younger; late surgery group: older than 3 months) and postoperative complications were compared. Visual outcome was analyzed in those with a follow-up period of more than 1 year.

Results:
Early surgery was performed in 24 eyes of 13 patients (11 bilateral and 2 unilateral) and late surgery in 23 eyes of 13 patients (10 bilateral and 3 unilateral). Intraoperatively, all eyes had poor pupillary dilatation and 6 (12.8%) eyes needed iris hooks. Postoperatively, the most common early complication was transient corneal edema observed in 22 (46.8%) eyes (13 and 8 eyes in the early and late surgery groups, respectively). Late complications included visual axis opacification in 6 (12.76%) eyes (3 in each group), and secondary glaucoma in 5 (10.64%) eyes (2 and 3 eyes in the early and late surgery groups, respectively). Vision was normal for age in 18 (60%) of the bilateral cases with a follow-up period of more than 1 year.

Conclusions:
Early surgical intervention for congenital cataract in eyes with microcornea can result in favorable outcomes with an acceptable rate of postoperative complications.

[
J Pediatr Ophthalmol Strabismus
. 2018;55(1):30–36.]