Search results for "Opium"

Aggregation of [Ln(12)(III)] clusters by the dianion of 3-formylsalicylic acid. Synthesis, crystal structures, magnetic and luminescence properties

2019

Three isostrucutral dodecanuclear clusters with the general formula [Ln(12)(fsa)(12)(mu f(3)-OH)(12)(DMF)(12)]center dot nDMF (fsa(2-) is the dianion of 3-formylsalicylic acid; Ln = Eu 1, Gd 2, Dy 3) have been obtained from the reaction of fromylsalicyclic acid (H(2)fsa), tetrabutylammonium hydroxide and Ln(NO3)(3)center dot 6H(2)O in methanol/DMF. Their structure consists of four vertex-sharing heterocubanes. Each heterocubane unit is assembled from four Ln(III) ions, three mu(3)-OH groups and one mu(3)-oxygen atom arising from the fsa(2-) carboxylato group. The photophysical properties of the europium derivative investigated at both 300 and 80 K sustain a relative intense emission obtaine…

Pressure-induced instability of the fergusonite phase of EuNbO4 studied by in situ Raman spectroscopy, x-ray diffraction, and photoluminescence spect…

2020

In this article, we present high-pressure experimental investigations on EuNbO4, an interesting technologically important material, using synchrotron based x-ray powder diffraction, Raman spectroscopy, and europium photoluminescence measurements up to 39.2, 31.6, and 32.4 GPa, respectively. All three techniques show the stability of the ambient monoclinic phase until 20 GPa. Beyond that, a pressure-induced structural phase transition takes place with the coexistence of two phases over a wide pressure range. The structure of the high-pressure phase has been determined as orthorhombic (space group: Imma) with a volume discontinuity of nearly 9% at the transition indicating the nature of trans…

New low-temperature phosphate glasses as a host for Europium Ions

2021

Abstract Artificial lightining, especially that of light emitting diodes, and telecommunications are penetrating every part of human lives daily. Different compositions phosphate glasses were suggested as a suitable host material for Eu3+ ions. Here rare earth metal ions act as luminescent centers also perturbing the bond order of phosphate glass network comprised of (PO4)3−, [−(O)PO3]2−, [−(O)2PO2]−, [−(O)3PO] structural units, which is indicated by Raman spectroscopy, confirming successful integration of aforementioned ions into the glass material. Glasses doped with Eu3+ ions show their typical photoluminescence spectra in low symmetry environment, consisting of the highest intensity 5D0…

2021

Atomic layer deposition (ALD) technology has unlocked new ways of manipulating the growth of inorganic materials. The fine control at the atomic level allowed by ALD technology creates the perfect conditions for the inclusion of new cationic or anionic elements of the already-known materials. Consequently, novel material characteristics may arise with new functions for applications. This is especially relevant for inorganic luminescent materials where slight changes in the vicinity of the luminescent centers may originate new emission properties. Here, we studied the luminescent properties of CaS:Eu by introducing europium with oxygen ions by ALD, resulting in a novel CaS:EuO thin film. We …

Synthesis of Eu<sup>2+</sup> and Dy<sup>3+</sup> Doped Strontium Aluminates and their Properties

2016

Strontium aluminate phosphors were synthesized by the solution combustion method using citric acid, urea or glycine as reducing agent and europium and dysprosium as dopants. The content of both dopants was in the range of 1 – 2 mol%. Dependence of phase composition, crystallite size and specific surface area on calcinations temperature, used reducing agents and dopants were determined. Luminescent properties of the calcinated at 1300 °C powders contained SrAl2O4 (90 %) and Sr4Al24O25 (10%) phases with crystallite size of 80 nm were determined.

Chemical shift reagents in the study of polycyclic alcohols IX—1H NMR spectra of myrtenol and some other primary alcohols

1974

Structure proof of (—)-myrtenol, 3-cyclopentenyl-1-methanol and 5-norbornene-2-endo-methanol has been obtained from their proton magnetic resonance spectra in carbon tetrachloride containing different added amounts of tris(dipivaloylmethanato)europium. For each alcohol, a 1:1 complex structure with Eu(dpm)3 could be computed, in which the calculated pseudocontact shift effects on all skeleton protons of the ring system were consistent with the observed shift effect values. A considerable contact contribution of opposite sign to that of the pseudocontact part of the effect could be estimated for the methylene protons of the CH2OH group.

Once-daily tiotropium Respimat® 5 μg is an efficacious 24-h bronchodilator in adults with symptomatic asthma

2015

SummaryIntroductionOnce-daily tiotropium Respimat® 5 μg is an efficacious add-on therapy to inhaled corticosteroids (ICS) with or without long-acting β2-agonists in patients with symptomatic asthma. The objective of this study was to investigate whether the dosing regimen of tiotropium (once- versus twice-daily), delivered via the Respimat® SoftMist™ inhaler, affected 24-h bronchodilator efficacy and safety versus placebo Respimat® in patients with asthma who were symptomatic despite medium-dose ICS therapy.MethodsA randomised, double-blind, placebo-controlled, crossover study with 4-week treatment periods of tiotropium 5 μg (once-daily, evening) and 2.5 μg (twice-daily, morning and evening…

Tiotropium Respimat® in asthma: a double-blind, randomised, dose-ranging study in adult patients with moderate asthma

2013

Tiotropium, a once-daily long-acting anticholinergic bronchodilator, when administered via Respimat® SoftMist™ inhaler (tiotropium Respimat®) significantly reduces the risk of severe exacerbations and improves lung function in patients with severe persistent asthma that is not fully controlled despite using inhaled corticosteroids (ICS) and long-acting β2-agonists. To further explore the dose–response curve in asthma, we investigated the efficacy and safety of three different doses of tiotropium Respimat® as add-on to ICS in symptomatic patients with moderate persistent asthma. In this randomised, double-blind, placebo-controlled, four-way crossover study, patients were randomised to tiotro…

Effect of QVA149 on lung volumes and exercise tolerance in COPD patients: The BRIGHT study

2014

Summary Introduction QVA149 is a novel, inhaled, once-daily dual bronchodilator containing a fixed-dose combination of the long-acting β 2 -agonist indacaterol and the long-acting muscarinic antagonist glycopyrronium (NVA237), for the treatment of chronic obstructive pulmonary disease (COPD). This study evaluated the effects of QVA149 on exercise tolerance, hyperinflation, lung function and lung volumes versus placebo and tiotropium. Methods Patients with moderate-to-severe COPD were randomized to QVA149 110/50 μg, placebo or tiotropium 18 μg once daily in a blinded, 3-period crossover study for 3 weeks. The primary endpoint was exercise endurance time at Day 21 for QVA149 versus placebo. R…

Urine tropenol ester levels in workers handling tiotropium bromide synthesis: implications for exposure prevention and biomonitoring

2019

Tropenol ester is a highly toxic anticholinergic substance and an intermediate used in industrial production of the bronchodilator tiotropium bromide. The aim of this study was to systematically test workers involved in its production for tropenol ester in urine to identify any exposure pathways and define additional preventive measures. Twelve workers performing tasks involving potential exposure to tropenol ester were repeatedly monitored at the end of each production cycle. Medical exams revealed no symptoms of acute poisoning with tropenol ester, but biological monitoring of urine showed 36 positive findings in 79 samples, with tropenol ester concentrations ranging between the detection…