Temperature and Magnetic Field-Assisted Switching of Magnetization and Observation of Exchange Bias in YbCrO₃ Nanocrystals

In this paper, we demonstrate an interesting feature in YbCrO₃ (YCO) nanocrystals, in which the material shows temperature and external magnetic field-assisted switching (a complete sign reversal) of zero field cooled magnetization (<i>M</i>_ZFC) and observation of exchange bias (EB) as a result of competing spin interaction at low temperature. This feature can be applied in nonvolatile memories, where, simply by changing the magnitude of the <i>H</i>_ext and <i>T</i>, the polarity of the magnetization can be switched between negative and positive. We also observed negative magnetization in YCO. Our results showed that, below its Nèel temperature (<i>T</i>_N ≈ 119 K), the <i>M</i>_ZFC crosses over to negative sign for <i>H</i> < 1000 Oe. At 60 K, YCO showed a significant negative <i>M</i>_ZFC ≈ −0.05 emu/g (at 100 Oe) due to the competing effects of Yb^<i>3+</i>, Cr³⁺ spins, thermal activation energy, and <i>H</i>_ext. At further lower temperatures, the <i>M</i>_ZFC showed a crossover to positive values, and the crossover temperature showed the dependence on <i>H</i>_ext (∼19 K for 100 Oe curve). The YCO also showed <i>H</i>_ext and <i>T</i>-dependent <i>H</i>_EB, which changed its sign with <i>T</i>. The observed <i>T</i>-dependent sign reversal in the EB was closely associated with the sign reversal of <i>M</i>_ZFC. The symmetric shift in field-cooled isothermal hysteresis curves confirmed that the observed EB was not due to the unsaturated minor loop. The training cycle further confirmed that the <i>H</i>_EB value decreased to ∼2% of the initial value of observed EB, which was very small compared to the observed <i>H</i>_EB in YCO, which indicated stable spin configuration at the locally formed ferromagnetic/antiferromagnetic interface

Physical Mechanism Behind Enhanced Photoelectrochemical and Photocatalytic Properties of Superhydrophilic Assemblies of 3D-TiO₂ Microspheres with Arrays of Oriented, Single-Crystalline TiO₂ Nanowires as Building Blocks Deposited on Fluorine-Doped Tin Oxide

In comparison to the one-dimensional (1D) semiconductor nanostructures, the hierarchical, three-dimensional (3D) microstructures, composed of the arrays of 1D nanostructures as building blocks, show quite unique physicochemical properties due to efficient photon capture and enhanced surface to volume ratio, which aid in advancing the performance of various optoelectronic devices. In this contribution, we report the fabrication of surfactant-free, radially assembled, 3D titania (rutile-phase) microsphere arrays (3D-TMSAs) composed of bundles of single-crystalline titania nanowires (NWs) directly on fluorine-doped conducting oxide (FTO) substrates with tunable architecture. The effects of growth parameters on the morphology of the 3D-TMSAs have been studied thoroughly. The 3D-TMSAs grown on the FTO-substrate showed superior photon-harvesting owing to the increase in light-scattering. The photocatalytic and photon to electron conversion efficiency of dye-sensitized solar cells (DSSC), where the optimized 3D-TMSAs were used as an anode, showed around 44% increase in the photoconversion efficiency compared to that of Degussa P-25 as a result of the synergistic effect of higher surface area and enhanced photon scattering probability. The TMSA film showed superhydrophilicity without any prior UV irradiation. In addition, the presence of bundles of almost parallel NWs led to the formation of arrays of microcapacitors, which showed stable dielectric performance. The fabrication of single-crystalline, oriented, self-assembled TMSAs with bundles of titania nanowires as their building blocks deposited on transparent conducting oxide (TCO) substrates has vast potential in the area of photoelectrochemical research

Synthesis of 2‑Nitroglycals from Glycals Using the Tetrabutylammonium Nitrate–Trifluoroacetic Anhydride–Triethylamine Reagent System and Base-Catalyzed Ferrier Rearrangement of Acetylated 2‑Nitroglycals

A reagent system comprising tetrabutylammonium nitrate–trifluoroacetic anhydride–triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-<i>O</i>-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity has been examined, and some of the products have been converted into 2,3-diamino-2,3-dideoxyglycosides and methyl <i>N</i>-acetyl-d-lividosaminide

Synthesis of 2‑Nitroglycals from Glycals Using the Tetrabutylammonium Nitrate–Trifluoroacetic Anhydride–Triethylamine Reagent System and Base-Catalyzed Ferrier Rearrangement of Acetylated 2‑Nitroglycals

A reagent system comprising tetrabutylammonium nitrate–trifluoroacetic anhydride–triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-<i>O</i>-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity has been examined, and some of the products have been converted into 2,3-diamino-2,3-dideoxyglycosides and methyl <i>N</i>-acetyl-d-lividosaminide

Inhibition of α-Glucosidase Enzyme by “Click” Inspired Pharmacophore Framework 1,3,4-Thiadiazole-1,2,3-Triazole Hybrids - supplementary material

checkCIF/PLATON reports  1H-NMR spectra of all the compounds   13C-NMR spectra of all the compounds   SC-XRD data of compounds 4 and 5    HRMS spectra of all the compounds    IC50 curves of all the compounds   Lineweaver-Burk plots of 9n, 9e, 9m and 9h    Secondary plots of 9n, 9e, 9m and 9h </p

Causes of post-operative visual impairment in the 1^st and 2^nd or higher generation Indian migrants living in Singapore.

<p>PVA = presenting visual acuity; BCVA = best-corrected visual acuity.</p><p>“Other” included one individual with pterygium, one with phthisis, one with trauma and one with myopic maculopathy. The exact cause in three individuals cannot be determined.</p

Comparison of prevalence, risk factors and outcomes of cataract surgery from selected population-based studies in Asia.

<p>APEDS = Andhra Pradesh Eye Disease Study; SiMES = Singapore Malay Eye Study; SINDI = Singapore Indian Eye Study; ACES = Aravind Comprehensive Eye Study; CIEMS = Central India Eye & Medical Study; BCVA = best corrected visual acuity; PCO = posterior capsular opacification; CME = cystoid macular edema; AMD = age-related macular degeneration; DR = diabetic retinopathy.</p><p>“−”: not reported.</p>*<p>Age-standardized to the Indian adult population from the 2010 Singapore Census.</p

Socioeconomic and systemic factors associated with post-operative visual impairment in the 1^st and 2^nd or higher generation Indian migrants living in Singapore.

<p>VI = visual impairment, defined as presenting visual acuity ≤20/60. OR = odds ratio; CI = confidence interval.</p>*<p>p<0.05.</p

Flow diagram of the measurement protocol.

<p>Flow diagram of the measurement protocol.</p

Prevalence of cataract surgery by country of birth: 1^st and 2^nd or higher generation Indian immigrants living in Singapore.

<p>N = number of individuals in the age group; CI = confidence interval.</p>*<p>Any cataract surgery was defined as lens extraction (pseudophakia or aphakia) in either or both eyes.</p>†<p>Age- and gender-adjusted to the Indian adult population from the 2010 Singapore census.</p>§<p>Bilateral cataract surgery was defined as lens extraction (pseudophakia or aphakia) in both eyes.</p