Search results for " powder"
showing 10 items of 93 documents
Synthesis of Fullerene- and Nanotube-Like SnS2 Nanoparticles and Sn/S/Carbon Nanocomposites
2009
SnS2 nested fullerene-type (IF) nanoparticles, nanotubes, and SnS2/C hybrid nanostructures were obtained by vapor transport starting from elemental tin and CS2. The reaction was carried out in a single-step process by heating elemental tin metal powder in a horizontal tube furnace at 800−1000 °C. TEM analysis allowed proposing a plausible mechanism for the formation of fullerene-like particles of SnS2 as well as tubes and scrolls from nanosheets of SnS2. Pure material could be obtained by optimizing the reaction based on a product analysis using powder X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) combined with energy-dispersive X-ray spectroscopy (EDX…
Neutron powder diffraction study in the mixed molecular system (NaCN)1−x(KCN)x
1989
A detailed structural analysis of (NaCN${)}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$(KCN${)}_{\mathrm{x}}$ mixed crystals with x=0.02, 0.19, and 0.95 was performed by neutron powder diffraction. The structural parameters of the cubic phases were refined, applying a model of preferred orientations. Different noncubic low-temperature phases were observed for x=0.02 and 0.95. For x=0.02 the antiferroelectric ordering of ${\mathrm{CN}}^{\mathrm{\ensuremath{-}}}$ dipoles at low temperatures is accompanied by significant alkali-alkali and alkali-${\mathrm{CN}}^{\mathrm{\ensuremath{-}}}$ sublattice shifts. Structural data are presented together with previous results for mixed crystals with x=0.59 and…
Location of Water and Xylene Molecules Adsorbed on Prehydrated Zeolite BaX. A Low-Temperature Neutron Powder Diffraction Study
1999
Magnetoelectric coupling driven by inverse magnetostriction in multiferroic BiMn3Mn4O12
2013
By means of neutron powder diffraction, we investigated the effect of the polar Bi$^{3+}$ ion on the magnetic ordering of the Mn$^{3+}$ ions in BiMn$_3$Mn$_4$O$_{12}$, the counterpart with \textit{quadruple} perovskite structure of the \textit{simple} perovskite BiMnO$_3$. The data are consistent with a \textit{noncentrosymmetric} spacegroup $Im$ which contrasts the \textit{centrosymmetric} one $I2/m$ previously reported for the isovalent and isomorphic compound LaMn$_3$Mn$_4$O$_{12}$, which gives evidence of a Bi$^{3+}$-induced polarization of the lattice. At low temperature, the two Mn$^{3+}$ sublattices of the $A'$ and $B$ sites order antiferromagnetically (AFM) in an independent manner …
Persistent lipsticks and their lip prints: new hidden evidence at the crime scene
2000
Latent lip print test results produced by permanent lipsticks are presented in this work. This cosmetic product, contrary to conventional lipsticks, does not leave visible prints and can thus be overlooked at the crime scene. As print vehicles the study used ceramics, glass, cotton fabric and paper. Lip prints were left to dwell for different periods and were later developed using aluminum powder, cobalt oxide powder and magnetic powder. The results show that identifiable lip prints can be obtained up to 30 days after being produced.
Low-temperature polymorphism in tungsten trioxide powders and its dependence on mechanical treatments
1999
The polymorphism of WO3 powder samples, resulting from mild mechanical treatments and from temperature changes between 30 K and room temperature, has been investigated by using Raman spectroscopy and X-ray di⁄raction. A transition from the monoclinic (I) c-phase to the triclinic d-phase after moderate mechanical treatments has been observed for untreated powder, just what happens when the same samples are rapidly cooled to low-temperature. Evidences of the low temperature monoclinic (II) polar e-phase have been found at room temperature in samples after a stronger milling treatment. The sequence of the low-temperature phase transitions appears to be strongly dependent on the mechanical hist…
Fluticasone/formoterol combination therapy versus budesonide/formoterol for the treatment of asthma: a randomized, controlled, non-inferiority trial …
2012
The inhaled corticosteroid fluticasone propionate (fluticasone) and the long-acting β₂ agonist formoterol fumarate (formoterol) have been combined in a single aerosol inhaler fluticasone/formoterol (flutiform(®)). This study compared the efficacy and safety of fluticasone/formoterol with the combination product budesonide/formoterol (Symbicort(®) Turbohaler(®)).A randomized, double-blind, double-dummy, multicenter, Phase 3 study comprising a 7- (± 3) day screening, 2-4-week run-in, and 12-week treatment periods. Patients aged ≥ 12 years with moderate to severe persistent asthma for ≥ 6 months before screening and forced expiratory volume in one second (FEV₁) 50-80% predicted and ≥ 15% rever…
Which factors affect the choice of the inhaler in chronic obstructive respiratory diseases?
2015
Inhalation is the preferred route of drug administration in chronic respiratory diseases because it optimises delivery of the active compounds to the targeted site and minimises side effects from systemic distribution. The choice of a device should be made after careful evaluation of the patient's clinical condition (degree of airway obstruction, comorbidities), as well as their ability to coordinate the inhalation manoeuvre and to generate sufficient inspiratory flow. These patient factors must be aligned with the specific advantages and limitations of each inhaler when making this important choice. Finally, adherence to treatment is not the responsibility of the patient alone, but should …
What drives inhaler prescription for asthma patients? Results from a real-life retrospective analysis
2020
Abstract Background The choice of inhaler device for asthma patients depends upon multiple attributes. We investigated factors that may drive general practitioners (GPs) and respiratory specialists in the prescription of inhaler devices for asthma patients who initiated inhalation therapy. Methods We retrospectively analysed prescriptions by GPs and respiratory specialists to asthma patients commencing inhaled corticosteroid/long-acting β2-agonist combination therapy available as both pressurised metered-dose inhalers (pMDIs) and dry powder inhalers (DPIs). Patient characteristics were compared by device and multivariate analysis was used to model the likelihood of receiving a pMDI as oppos…
Defect detection in laser powder deposition components by laser thermography and laser ultrasonic inspections
2013
Laser Powder Deposition (LDP) techniques are being adopted within aerospace and automotive manufacturing to produce innovative precision components. Non-destructive techniques (NDT) for detecting and quantifying flaws within these components enables performance and acceptance criteria to be verified, improving product safety and reducing ongoing maintenance and product repair costs. In this work, software enabled techniques are presented for in-process analysis of NDT laser ultrasonic signals and pulsed laser thermography images of sequential metallic LPD layers. LPD tracks can be as thin as 200μm while deposited at a rate of 500 mm/min, requiring ultrafast inspection and processing times. …