The curious case of offset bars : markers for a baby galaxy disk or signposts of an interaction with dark matter sub halos?

>Magister Scientiae - MScWe have used the Spitzer Survey of Stellar Structure in Galaxies (S⁴G) as a representative sample of the local universe (total of 2352 galaxies in S⁴G) to make a catalog of offset disk barred galaxies. Using the combined variation of the position angle and the ellipticity (provided by ellipse fit) and also through visual inspection, we have been able to identify all offset structures in S⁴G. While primary bars are present in 2=3 of the disk galaxies in the visible universe, offset bars have a much lower fraction. Of the ̴ 1500 (3.6µm images) disk galaxies available in S⁴G, we classified only 49 as offset barred disk galaxies. We have determined basic properties (bar to total luminosity ratio, bar length, disk scale-length and bars of offset bars shape) using GALFIT, a widely used galaxy decomposition software package. Our main conclusion is that all the offset bars are boxy, independent of their offset from the galaxy center, or the mass of the host galaxy. Additionally we find that, the early type offset bars seem to be more boxy than the late types. The comparison of our offset sample with two other samples, respectively, low mass and high mass normal barred galaxies ("normal" for bars located at the photometric center of the host galaxy), reveals them to be at an intermediate position between the two normal samples. The bar length, disk scale-length and bar to total luminosity ratio are on average larger than the low mass normal and smaller than high mass normal barred galaxies. We have found, overall, a tighter correlation between the disk and bar properties for offset bars in comparison to the two normal samples. Our explanation is that, although the offset has no visible impact on the global shape of the bars, the process responsible for these disturbances seems to affect the star formation rate such that their disk and bars are on average more active than the normal barred galaxies in the same mass range, but not enough to surpass normal barred galaxies with much higher mass

Selective Catalytic Reduction of NO_<i>x</i> with NH₃ over Novel Fe–Ni–Ti Catalyst

A novel Fe–Ni–Ti composite oxide prepared via the hydrothermal method has been developed for the selective catalytic reduction of NO_<i>x</i> with NH₃. This environmentally benign catalyst showed high activity and excellent selectivity to N₂, which is superior to that of Fe–Ti and Ni–Ti catalysts. Catalyst characterization results revealed that over Fe–Ni–Ti catalyst the dual redox cycles (Fe³⁺ + Ni²⁺ ↔ Fe²⁺ + Ni³⁺, Ti⁴⁺ + Ni²⁺ ↔ Ti³⁺ + Ni³⁺) are crucial for the enhanced activity. The synergetic effect among Fe, Ni, and Ti leads to not only the increased redox property, but also improved surface acidity. DRIFT experiments demonstrated that more reactive NH₃/NH₄⁺ and M-NO₂ nitro species formed over Fe–Ni–Ti catalyst, thus resulting in the efficiently catalytic removal of NO_<i>x</i>

Rigid-Rod Sulfonated Polyamide as an Aqueous-Processable Binder for Li-Ion Battery Electrodes

Polymer binders are important components of most battery electrodes, ensuring high performance and long-term durability. Increasing demand for lithium-ion batteries in the automotive, stationary power, and portable electronics industries calls for a greener binder to replace poly(vinylidene difluoride) (PVDF). We evaluate the performance of aqueous solution-processed electrodes prepared with a rigid-rod polymer binder, poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT). The polyamide backbone and double-helical configuration of PBDT give rise to its mechanical strength and rigidity, and its functional nature (H-bonding amides and sulfonates) can provide specific binding with electrode particles. LiFePO4 electrodes prepared with 3 wt % PBDT show mechanical integrity and cycling stability, achieving over 1000 cycles at 4C rate with negligible capacity decay. These electrodes demonstrate comparable rate performance with their PVDF counterparts while eliminating fluorine from the electrode as well as the organic solvents needed for processing. This study reveals that PBDT holds great potential as a binder for advanced sustainable batteries

Supplementary document for In situ measurement of stiffness increase in posterior sclera after UV-riboflavin crosslinking by optical coherence elastography - 5997340.pdf

This document provides additional details related to the paper "In situ measurement of stiffness increase in posterior sclera after UV-riboflavin crosslinking by optical coherence elastography"

Adsorption and Hydrogenation of Acrolein on Ru(001)

Temperature-programmed reaction spectroscopy (TPRS) and reflection absorption infrared spectroscopy (RAIRS) were used to study the adsorption and hydrogenation of acrolein on Ru(001). At low coverages, acrolein adsorbs on the surface at 90 K mostly via the CO bond and completely decomposes to CO around 460 K. As the coverage increases, adsorption via the CC bond predominates and most of the acrolein either desorbs molecularly or decomposes to CO and H₂. However, a small amount of the acrolein also self-hydrogenates to yield all the possible hydrogenation products, propanal, 2-propenol, and 1-propanol, with TPRS peak temperatures of 180, 210, and 280 K respectively, with propanal having the highest yield. Co-adsorption with hydrogen enhances the adsorption via the CC bond and the yield of all the hydrogenation products. The formation of propanal and 1-propanol was also confirmed by RAIRS to occur at approximately the same temperatures as observed with TPRS, with the intensity of the RAIRS peaks indicating that the extent of hydrogenation is significantly higher than the yields obtained from TPRS

Detection of urine BPA, NP and OP in the uterine leiomyoma group (n = 98).

<p>Detection of urine BPA, NP and OP in the uterine leiomyoma group (n = 98).</p

Two new echinocystic acid derivatives catalyzed by filamentous fungus <i>Gliocladium roseum</i> CGMCC 3.3657

<p>Biotransformation of Echinocystic acid (EA,<b>1</b>) using <i>G. roseum</i> CGMCC 3.3657 has been investigated, which leads to the isolation and identification of two novel Echinocystic acid derivatives, 4, 16α-dihydroxy-3,4-seco-olean-12-en-3,28-dioic acid (<b>2</b>) and 16α-hydroxy, A-homo-3α-oxa-olean-12-en-3-one-28-oic acid (<b>3</b>). Their structures have been elucidated by analysis of spectroscopic data. This biocatalysis could serve as an efficient tool complementary to classical chemical methods for the transformation of EA.</p

Concentrations of urine environmental estrogens (ng mL⁻¹) in participants of uterine leiomyoma and control group (mean±SD, n = 156).

<p>(1)Participants with gravida > 3,compared with control group,<i>P</i><0.05);(2)Participants with gravida ≤ 3,compared with control group,<i>P</i><0.05).</p

Mesoporous Zirconium Phosphonate Hybrid Material as Adsorbent to Heavy Metal Ions

A new kind of inorganic–organic hybrid zirconium phosphonate material (NTAZP) with mesoporous structure was synthesized using nitrilotris­(methylene)-triphosphonic acid (ATMP) and zirconium dichloride oxide octahydrate. The sample possesses a spherical morphology, and the spheres are composed of lobular lamellae. The lobular lamellae have the structure of a worm-like mesoporous (about 2.7 nm) framework and a high surface area (about 160.4 m²/g), which were characterized by SEM, TEM, N₂ sorption, XRD, TG-DTA, elemental analysis, TOC (total organic carbon), XPS, and FT-IR spectroscopy techniques. The as-prepared NTAZP was used as adsorbent for the efficient removal of heavy metal ions (e.g., Pb²⁺, Cu²⁺, and Cd²⁺). Our results indicate that the material has good prospects for application as an adsorbent in wastewater processing

Detection of blood plasma BPA, NP and OP in the control group (n = 126).

<p>Detection of blood plasma BPA, NP and OP in the control group (n = 126).</p