Production and characterization of titanium and iron oxide nano-sized thin films

We present a simple and reproducible method to obtain TiO2 and Fe2O3 mixed-oxide thin films by reactive radio-frequency sputtering. The influence of iron concentration on the structural properties of the layers has been studied. Structural characterization, carried out by electron microscopy analysis, allowed one to correlate the inhibition of the grain growth of titania to the presence of iron oxide and to its segregation at grain boundaries. This behavior should be ascribed to a superficial-tension phenomenon. As a possible application of these thin films, we have investigated the gas-sensing properties toward CO, with particular focus on the role of Fe. The layers were capable to sense CO down to the level requested for environmental monitoring.

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SYNTHESIS AND CHARACTERIZATION OF HG-BASED SUPERCONDUCTING THIN FILMS PRODUCED STARTING FROM LASER-DEPOSITED PRECURSORS

International Journal of Modern Physics B ◽

10.1142/s021797920000248x ◽

2000 ◽

Vol 14 (25n27) ◽

pp. 2731-2736 ◽

Cited By ~ 1

Author(s):

M. BINDI ◽

F. FUSO ◽

N. PUCCINI ◽

E. ARIMONDO ◽

A. TAMPIERI ◽

...

Keyword(s):

Thin Films ◽

Laser Deposition ◽

Precursor Film ◽

Superconducting Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Electron Microscopy Analysis ◽

Zero Resistance ◽

Microscopy Analysis

Correctly c-axis oriented HgBa 2 CaCu 2 O 6+δ thin films have been produced on (100) MgO single crystal substrates and characterized. Pulsed laser deposition has been exploited to deposit Hg-free Re-doped precursor which then underwent synthesis in evacuated and sealed quartz tubes. X-ray diffraction pattern of the precursor target shows the expected composition of oxides. Scanning electron microscopy analysis have been performed on the surface of the precursor film. Hg-1212 films have been analyzed by θ-2θ Bragg-Brentano X-ray diffractometry. The patterns show little contributions in composition of Hg-1223 phase. The films exhibit a transition temperature >120 K with zero-resistance at around 115 K.

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Growth and characterization of NdBa2Cu3O7-x thin films deposited by d.c. sputtering

International Journal of Modern Physics B ◽

10.1142/s0217979200002740 ◽

2000 ◽

Vol 14 (25n27) ◽

pp. 2664-2669

Author(s):

M. C. CUCOLO ◽

A. M. CUCOLO

Keyword(s):

Thin Films ◽

X Ray Diffraction ◽

Surface Stability ◽

Deposition Parameters ◽

High Oxygen Pressure ◽

Fabrication Procedure ◽

Electron Microscopy Analysis ◽

Microscopy Analysis ◽

Diffraction Patterns

Among the ReBa 2 Cu 3 O 7-x (ReBCO, Re=rare earth) cuprate family the NdBa 2 Cu 3 O 7-x system (NdBCO) is known to have the highest critical temperature and critical current. Moreover, in comparison with the YBa 2 Cu 3 O 7-x compound, NdBCO shows a better surface stability and morfology that are basic requirements for the realization of high temperature superconducting (HTS) devices. We have investigated the fabrication procedure of NdBCO films on (001) SrTiO 3 substrates using a dc sputtering technique in high oxygen pressure. The effect of several deposition parameters on the structural and superconducting properties of the NdBCO thin films, has been investigated. The x-ray diffraction patterns showed that the deposited films were c-axis oriented without any impurity phase. The surface morfology was studied by a standard Scanning Electron Microscopy analysis (SEM). T c (ρ=0) ≥ 91 K and J c (77 K ) ≤ 0.6 106 A/cm 2 have been obtained at the optimized sputtering conditions.

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Antiparasitic Properties of Cardiovascular Agents against Human Intravascular Parasite Schistosoma mansoni

Pharmaceuticals ◽

10.3390/ph14070686 ◽

2021 ◽

Vol 14 (7) ◽

pp. 686

Author(s):

Raquel Porto ◽

Ana C. Mengarda ◽

Rayssa A. Cajas ◽

Maria C. Salvadori ◽

Fernanda S. Teixeira ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Screening Strategy ◽

Early Infection ◽

Global Public Health ◽

Parasitic Worm ◽

Electron Microscopy Analysis ◽

Health Significance ◽

Microscopy Analysis

The intravascular parasitic worm Schistosoma mansoni is a causative agent of schistosomiasis, a disease of great global public health significance. Praziquantel is the only drug available to treat schistosomiasis and there is an urgent demand for new anthelmintic agents. Adopting a phenotypic drug screening strategy, here, we evaluated the antiparasitic properties of 46 commercially available cardiovascular drugs against S. mansoni. From these screenings, we found that amiodarone, telmisartan, propafenone, methyldopa, and doxazosin affected the viability of schistosomes in vitro, with effective concentrations of 50% (EC50) and 90% (EC90) values ranging from 8 to 50 µM. These results were further supported by scanning electron microscopy analysis. Subsequently, the most effective drug (amiodarone) was further tested in a murine model of schistosomiasis for both early and chronic S. mansoni infections using a single oral dose of 400 mg/kg or 100 mg/kg daily for five consecutive days. Amiodarone had a low efficacy in chronic infection, with the worm and egg burden reduction ranging from 10 to 30%. In contrast, amiodarone caused a significant reduction in worm and egg burden in early infection (>50%). Comparatively, treatment with amiodarone is more effective in early infection than praziquantel, demonstrating the potential role of this cardiovascular drug as an antischistosomal agent.

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