First in-beam application of thallium bromide semiconductor detectors to particle-induced X-ray emission

For the first time, particle-induced X-ray emission (PIXE) spectra were obtained using TlBr detectors. The TlBr detector was fabricated from a crystal grown with material purified by the zone purification. Its active volume was 1.5 mm × 1.5 mm × 3.1 mm, and it exhibited an energy resolution of a 6.2 keV full-width at half-maximum (FWHM) for 59.5 keV at room temperature. The detector was installed into a PIXE system at Aomori Prefecture Quantum Science Center. A Pb plate target in the PIXE chamber was irradiated with a 20 MeV proton beam, and X-ray peaks for Pb K[Formula: see text] and K[Formula: see text] were successfully detected by the TlBr detector at room temperature.

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CsOH and its Lighter Homologues – a Comparison

Zeitschrift für Naturforschung B ◽

10.5560/znb.2014-4163 ◽

2014 ◽

Vol 69 (11-12) ◽

pp. 1229-1236

Author(s):

Matthias Wörsching ◽

Constantin Hoch

Keyword(s):

Gas Phase ◽

Room Temperature ◽

Structure Type ◽

Alkali Metal Hydroxide ◽

X Ray ◽

Raman Spectroscopic ◽

Cesium Hydroxide ◽

Free Ion ◽

The One ◽

First Time

Abstract Cesium hydroxide, CsOH, was for the first time characterised on the basis of single-crystal data. The structure is isotypic to the one of the room-temperature modification of NaOH and can be derived from the NaCl structure type thus allowing the comparison of all alkali metal hydroxide structures. Raman spectroscopic investigations show the hydroxide anion to behave almost as a free ion as in the gas phase. The X-ray investigations indicate possible H atom positions.

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Physical Stability and Viscoelastic Properties of Co-Amorphous Ezetimibe/Simvastatin System

Pharmaceuticals ◽

10.3390/ph12010040 ◽

2019 ◽

Vol 12 (1) ◽

pp. 40 ◽

Cited By ~ 1

Author(s):

Justyna Knapik-Kowalczuk ◽

Krzysztof Chmiel ◽

Karolina Jurkiewicz ◽

Natália Correia ◽

Wiesław Sawicki ◽

...

Keyword(s):

Elevated Temperature ◽

Viscoelastic Properties ◽

Room Temperature ◽

Physical Stability ◽

Ternary Systems ◽

Storage Conditions ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Conditions ◽

First Time

The purpose of this paper is to examine the physical stability as well as viscoelastic properties of the binary amorphous ezetimibe–simvastatin system. According to our knowledge, this is the first time that such an amorphous composition is prepared and investigated. The tendency toward re-crystallization of the amorphous ezetimibe–simvastatin system, at both standard storage and elevated temperature conditions, have been studied by means of X-ray diffraction (XRD). Our investigations have revealed that simvastatin remarkably improves the physical stability of ezetimibe, despite the fact that it works as a plasticizer. Pure amorphous ezetimibe, when stored at room temperature, begins to re-crystallize after 14 days after amorphization. On the other hand, the ezetimibe-simvastatin binary mixture (at the same storage conditions) is physically stable for at least 1 year. However, the devitrification of the binary amorphous composition was observed at elevated temperature conditions (T = 373 K). Therefore, we used a third compound to hinder the re-crystallization. Finally, both the physical stability as well as viscoelastic properties of the ternary systems containing different concentrations of the latter component have been thoroughly investigated.

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Temperature dependence of the AV3O7 (A = Ca, Sr) structure

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768107050550 ◽

2007 ◽

Vol 63 (6) ◽

pp. 836-842 ◽

Cited By ~ 1

Author(s):

Sebastian Prinz ◽

Karine M. Sparta ◽

Georg Roth

Keyword(s):

Single Crystal ◽

Temperature Dependence ◽

Crystal Structures ◽

Room Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Space Groups ◽

Temperature Ranges ◽

First Time

The V4+ (spin ½) oxovanadates AV3O7 (A = Ca, Sr) were synthesized and studied by means of single-crystal X-ray diffraction. The room-temperature structures of both compounds are orthorhombic and their respective space groups are Pnma and Pmmn. The previously assumed structure of SrV3O7 has been revised and the temperature dependence of both crystal structures in the temperature ranges 297–100 K and 315–100 K, respectively, is discussed for the first time.

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Polymorphism in Ho2(MoO4)3

Powder Diffraction ◽

10.1017/s0885715613001176 ◽

2013 ◽

Vol 28 (S2) ◽

pp. S33-S40 ◽

Cited By ~ 4

Author(s):

C. González-Silgo ◽

C. Guzmán-Afonso ◽

V. M. Sánchez-Fajardo ◽

S. Acosta-Gutiérrez ◽

A. Sánchez-Soares ◽

...

Keyword(s):

Phase Transition ◽

Thermal Expansion ◽

Room Temperature ◽

Linear Expansion ◽

Negative Thermal Expansion ◽

Thermal Treatments ◽

Positive Coefficient ◽

X Ray ◽

Expansion Coefficients ◽

First Time

Two polymorphs of Holmium molybdate, known as β'-phase and γ-phase, were prepared by solid state reaction with different thermal treatments. These polycrystalline samples have been studied for the first time by X-ray thermodiffractometry from room temperature up to 1300 K. We found that the initial β'-phase undergoes a transition to a β-phase and then to a γ-phase. The γ (hydrated)-phase, turns to the γ (dehydrated)-phase and then to the β-phase. Each sequence involves a reversible and an irreversible phase transition for Ho2(MoO4)3. Both polymorphs have remarkable physical properties like nonlinear optics, ferroelectricity and negative thermal expansion. We have calculated the linear expansion coefficients of both phases. We have obtained a positive coefficient for the β'-phase and a negative one for the γ-phase. Moreover, we have made a comparison of the obtained coefficients with previous results for other rare earth molybdates.

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A Versatile New Reagent for Nitrosation under Mild Conditions

10.26434/chemrxiv.13726513 ◽

2021 ◽

Author(s):

Jordan D. Galloway ◽

Cristian Sarabia ◽

James C. Fettinger ◽

Hrant Hratchian ◽

Ryan Baxter

Keyword(s):

Room Temperature ◽

Computational Analysis ◽

Functional Group ◽

Nitroso Compounds ◽

Chemical Reagent ◽

Experimental Conditions ◽

X Ray ◽

Mild Conditions ◽

Rotational Isomers ◽

First Time

We report a new chemical reagent for transnitrosation under mild experimental conditions. This new reagent is stable to air and moisture across a broad range of temperatures, and is effective for transnitrosation in multiple solvents. Compared to traditional nitrosation methods, our reagent shows high functional group tolerance for substrates that are susceptible to oxidation or reversible transnitrosation. Several challenging nitroso-compounds are accessed here for the first time, including 15N isotopologues. X-ray data confirms two rotational isomers of the reagent are configurationally stable at room temperature, although only one isomer is effective for transnitrosation. Computational analysis describes the energetics of rotamer interconversion, including interesting geometry-dependent hybridization ef-fects.

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A Novel Cd(II) Isophthalate Complex with Triethanolamine: Crystal Structure, Fluorescence and Antimicrobial Activity

Acta Chimica Slovenica ◽

10.17344/acsi.2020.6620 ◽

2021 ◽

Vol 68 (2) ◽

pp. 466-474

Author(s):

Zuhal Yolcu ◽

Sinem Yurtcan ◽

Meryem Çıtlakoğlu

Keyword(s):

Antimicrobial Activity ◽

Room Temperature ◽

Diffusion Method ◽

Gram Negative Bacteria ◽

Single Crystal Diffraction ◽

X Ray ◽

Ft Ir ◽

First Time ◽

Trigonal Prismatic

A mixed ligand Cd(II) complex [Cd(IsoPht)(TEA)H2O]·3H2O was synthesized for the first time by using isophthalic acid (H2IsoPht) and tetradentate triethanolamine (TEA) and characterized by X-ray single-crystal diffraction, FT-IR, and thermogravimetric analysis (TGA). This novel complex crystallizes in the triclinic system with P-1 space group and distorted monocapped trigonal prismatic geometry. The Cd(II) has seven coordinates with bidentate IsoPht, a TEA in the tetradentate mode, and an aqua ligand. The fluorescence properties of the Cd(II) complex and TEA ligand were investigated at room temperature. The present Cd(II) complex was also tested for its antimicrobial activity by in vitro agar diffusion method against some Gram-positive and Gram-negative bacteria and a fungus.

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MBE-Grown GaNAsBi Matched to GaAs with 1.3-μm Emission Wavelength

MRS Proceedings ◽

10.1557/proc-829-b11.6 ◽

2004 ◽

Vol 829 ◽

Author(s):

Masahiro Yoshimoto ◽

Wei Huang ◽

Kunishige Oe

Keyword(s):

Room Temperature ◽

Molecular Beam ◽

Laser Diodes ◽

Diffraction Peak ◽

X Ray Diffraction ◽

X Ray ◽

Lattice Matching ◽

Peak Energy ◽

First Time ◽

Lattice Matched

ABSTRACTGaNyAs1-x-yBix alloy lattice-matched to GaAs has been grown by molecular beam epitaxy (MBE). The lattice-matching of GaNyAs1-x-yBix to GaAs was investigated by X-ray diffraction measurements on a series of GaNyAs1-x-yBix with various GaN molar fractions. GaNyAs1-x-yBix lattice-matched to GaAs was obtained, which was confirmed by its diffraction peak overlapped with the peak of GaAs. Photoluminescence (PL) of 1.3 μm was observed from GaNyAs1-x-yBix epilayer matched to GaAs at room temperature. The temperature coefficient of the PL peak energy in a temperature range 150–300K for GaNyAs1-x-yBix was 1/3 of InGaAsP with a bandgap corresponding to 1.3-μm emission. Both lattice-matching to GaAs and bandgap adjustment to 1.3-μm waveband were achieved for GaNyAs1-x-yBix for the first time. This alloy will lead to the fabrication of laser diodes with an emission of temperature insensitive wavelength.

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Bridgman Growth of a Novel Piezoelectric Single-Crystal Material: Ca3NbGa3Si2O14

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.217 ◽

2007 ◽

Vol 336-338 ◽

pp. 217-219

Author(s):

An Hua Wu ◽

Jia Yue Xu ◽

Juan Zhou ◽

Bao Liang Lu ◽

Xian Jun Wu ◽

...

Keyword(s):

Acoustic Wave ◽

Room Temperature ◽

Single Phase ◽

Bulk Acoustic Wave ◽

X Ray ◽

Homologous Compounds ◽

Vertical Bridgman ◽

Acoustic Loss ◽

First Time ◽

Potential Substrate

Langasite (La3Ga5SiO14, LGS) and its isomorphs, were regarded as potential substrate materials for surface acoustic wave (SAW) and bulk acoustic wave (BAW) applications. Among these homologous compounds, the ordered structure crystals have attracted much attention for their low Ga2O3 content, high acoustic velocity and low acoustic loss. In this work, the ordered langasite structure crystals Ca3NbGa3Si2O14 (CNGS) were grown with vertical Bridgman method for the first time. The CNGS crystals with 25mm in diameter and 40mm in length were grown successfully from its stoichiometric melt through LGS crystal of Ø10mm×40mm being chosen as seed. X-ray powder diffraction experiments showed that the CNGS single crystals had a single phase and had the same structure as the LGS crystal. The transmittance spectra with the wavelength from 200 to 800nm were recorded by means of Spectrophotometer at room temperature.

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Mineralogy and formation of evaporite deposits from the Lewis Cliff ice tongue, Antarctica

Antarctic Science ◽

10.1017/s0954102014000406 ◽

2014 ◽

Vol 27 (1) ◽

pp. 73-84 ◽

Cited By ~ 7

Author(s):

Tingting Liu ◽

David L. Bish ◽

Richard A. Socki ◽

Ralph P. Harvey ◽

Eric Tonui

Keyword(s):

Room Temperature ◽

Precipitation Process ◽

Secondary Mineral ◽

X Ray Diffraction ◽

Sulfate Ions ◽

X Ray ◽

Bodies Of Water ◽

Evaporite Minerals ◽

Glacial Tills ◽

First Time

AbstractThe mineralogy of evaporites from the Lewis Cliff ice tongue (LCIT), Antarctica, and their mineral stabilities and transformation behaviours under different temperature and relative humidity (RH) conditions have been evaluated to elucidate formation mechanism(s). A variety of sodium (Na)-rich evaporite minerals were documented using RH-controlled powder X-ray diffraction (XRD) methods including Na-sulfates (mirabilite and thenardite), Na-carbonate/bicarbonates (nahcolite, occasional trona and natron) and Na-borates (qilianshanite and borax). Mirabilite begins to dehydrate to thenardite, and natron to trona and natrite when exposed to room temperature, even when maintained at RH values similar to those measured at the LCIT (50–70%). The boron-mineral qilianshanite was discovered for the first time in Antarctica within the evaporite mounds. The mirabilite-rich mounds are deduced to have formed via a freezing/sublimation process that occurred in glacial or subglacial bodies of water supplied by glacial tills containing microbially oxidized sulfate ions. The needle-like nahcolite crystals growing on the exteriors of the mounds suggest a dissolution/precipitation process involving atmospheric CO2 and water. The co-existence of nahcolite and boron-bearing minerals indicates the presence of a Na+-, HCO3-- and boron-bearing alkaline brine, which produces qilianshanite as a secondary mineral by reaction of nahcolite and borax in atmospheric CO2 and H2O.

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