scholarly journals Nanostructural Arrangements and Surface Morphology on Ureasil-Polyether Films Loaded with Dexamethasone Acetate

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1362
Author(s):  
Joao Augusto Oshiro ◽  
Angelo Lusuardi ◽  
Elena M. Beamud ◽  
Leila Aparecida Chiavacci ◽  
M. Teresa Cuberes
Keyword(s):  
Film Surface ◽  
Crystalline Phases ◽  
Essential Information ◽  
X Ray ◽  
Force Microscopy ◽  
Ether Oxygen ◽  
Dexamethasone Acetate ◽  
Poly Ethylene ◽  
The One ◽  
Poly Propylene

Ureasil-Poly(ethylene oxide) (ureasil-PEO500) and ureasil-Poly(propylene oxide) (u-PPO400) films, unloaded and loaded with dexamethasone acetate (DMA), have been investigated by carrying out atomic force microscopy (AFM), ultrasonic force microscopy (UFM), contact-angle, and drug release experiments. In addition, X-ray diffraction, small angle X-ray scattering, and infrared spectroscopy have provided essential information to understand the films’ structural organization. Our results reveal that while in u-PEO500 DMA occupies sites near the ether oxygen and remains absent from the film surface, in u-PPO400 new crystalline phases are formed when DMA is loaded, which show up as ~30–100 nm in diameter rounded clusters aligned along a well-defined direction, presumably related to the one defined by the characteristic polymer ropes distinguished on the surface of the unloaded u-POP film; occasionally, larger needle-shaped DMA crystals are also observed. UFM reveals that in the unloaded u-PPO matrix the polymer ropes are made up of strands, which in turn consist of aligned ~180 nm in diameter stiffer rounded clusters possibly formed by siloxane-node aggregates; the new crystalline phases may grow in-between the strands when the drug is loaded. The results illustrate the potential of AFM-based procedures, in combination with additional physico-chemical techniques, to picture the nanostructural arrangements in polymer matrices intended for drug delivery.

Ni-Doped ZnO Thin Films: Deposition, Characterization and Photocatalytic Applications

2021 ◽  
Vol 21 (3) ◽  
pp. 1560-1569
Author(s):  
K. Moorthy ◽  
S. S. R. Inbanathan ◽  
C. Gopinathan ◽  
N. P. Lalla ◽  
Abdulaziz Ali Alghamdi ◽  
...  
Keyword(s):  
Thin Films ◽  
Uv Light ◽  
Characteristic Root ◽  
Film Surface ◽  
Hexagonal Wurtzite Structure ◽  
Zno Thin Films ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Doped Zno

Root like structured Ni-doped zinc oxide [Zn(1-x)NixO (x = 0.09)] thin films were deposited on a non-conducting glass substrate by indigenously developed spray pyrolysis system at optimized substrate hotness of 573±5 K. Thus obtained Ni-doped ZnO thin films were characterized by UV-visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Atomic Force Microscopy (AFM). XRD result revealed that Ni-doped ZnO has a polycrystalline nature with a hexagonal wurtzite structure. For pure ZnO and Ni-doped ZnO thin films, the particle sizes were 60.9 and 53.3 nm while lattice strain values were 1.56×10−3 and 1.14×10−3, respectively. The film surface showed characteristic root-like structure as observed by the SEM. It was observed that the Ni-doped ZnO thin films were grown in high density along with more extent of branching as compared to pure ZnO thin films but retained the root-like morphologies, however, the branches were more-thinner and of shorter lengths. AFM analysis showed that the surface grains of the Ni-doped samples are homogeneous with less RMS roughness values compared with the undoped ZnO samples. The photocatalytic activity of the prepared thin films was evaluated by the degradation of methyl orange (MO) dye under UV light irradiation. Pure ZnO and Ni-doped ZnO thin films took 150 min and 100 min to degrade about 60% MO dye, respectively.

X-ray photoelectron spectroscopy characterization and morphology of MgO thin films grown on single-crystalline diamond (100)

2002 ◽  
Vol 17 (8) ◽  
pp. 1914-1922 ◽  
Author(s):  
S. M. Lee ◽  
T. Ito ◽  
H. Murakami
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Film Surface ◽  
Growth Front ◽  
Electron Beam Evaporation ◽  
Single Crystalline ◽  
X Ray ◽  
Force Microscopy ◽  
Magnesium Peroxide ◽  
Surface Morphologies

The morphology and composition of MgO films grown on single-crystalline diamond (100) have been studied. MgO thin films were deposited in the substrate temperature range from room temperature (RT) to 723 K by means of electron beam evaporation using a MgO powder source. Atomic force microscopy images indicated that the film grown at RT without O2 supply was relatively uniform and flat whereas that deposited in oxygen ambient yielded higher growth rates and rough surface morphologies. X-ray photoelectron spectroscopy analyses demonstrate that the MgO film deposited at RT without O2 has the composition closest to that of the stoichiometric MgO and that a thin contaminant layer composed mainly of magnesium peroxide (before etching) or hydroxide (after etching) was unintentionally formed on the film surface, respectively.These results will be discussed in relation to the interaction among the evaporated species and intentionally supplied oxygen molecules at the growth front as well as the interfacial energy between diamond and MgO.

Dynamics of Nanocomposite Formation and Impact Modification of Polyethyleneterephthalate

2004 ◽  
Vol 856 ◽  
Author(s):  
Elif Alyamac ◽  
Ulku Yilmazer
Keyword(s):  
Ethylene Terephthalate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Poly Ethylene Terephthalate ◽  
Impact Modifier ◽  
Diffraction Patterns ◽  
Poly Ethylene ◽  
The One ◽  
Impact Modification ◽  
Ethylene Methyl Acrylate

ABSTRACTThis study was conducted to investigate the effects of component concentrations and addition order of the components, on the final properties of ternary nanocomposites composed of poly(ethylene terephthalate), organoclay, and an ethylene/methyl acrylate/glycidyl methacrylate (E-MA-GMA) terpolymer acting as an impact modifier for PET. Among the investigated addition orders, the best sequence of component addition (PI-C i.e. PET, Impact Modifier-Clay) was the one in which poly (ethylene terephthalate) was first compounded with E-MA-GMA. Later, this mixture was compounded with the organoclay in the subsequent run. In X-ray diffraction analysis, extensive layer separation associated with delamination of the original clay structure was observed in PI-C and (CI-P i.e. Clay, Impact Modifier-PET) sequences with both 1 and 3 wt. % clay contents. X-ray diffraction patterns showed that, at these conditions, exfoliated structures were obtained.

Nanogranular Fe-Cu-Ag Thin Films: Structure, Microstructure and Giant Magnetoresistance

2008 ◽  
Vol 8 (6) ◽  
pp. 2964-2970 ◽  
Author(s):  
S. Rout ◽  
Senthil M. Kumar ◽  
S. Bhattacharya ◽  
D. K. Aswal ◽  
S. K. Gupta
Keyword(s):  
Thin Films ◽  
Giant Magnetoresistance ◽  
Magnetic Particles ◽  
Film Surface ◽  
X Ray ◽  
Force Microscopy ◽  
Transmission Electron ◽  
Ag Particles ◽  
Surface Image ◽  
Microstructure Morphology

FexCuyAgz granular thin films with several compositions were prepared by dc magnetron sputtering. These films consist of small Fe magnetic particles embedded in a nonmagnetic CuAg matrix. Structure, microstructure, morphology and magnetotransport properties were studied. The compositions of these samples were determined by energy-dispersive X-ray analysis. X-ray diffraction results showed strong Ag(111) peaks and broad Cu(111) peaks in all the samples. The variation of the (111) lattice spacings indicates a partial intermixing of Fe, Cu and Ag atoms. Microstructural studies using transmission electron microscopy (TEM) on a selected sample showed only Ag reflections and no reflection from Cu and Fe. Both XRD and TEM studies did not reveal any diffraction peak due to Fe and Cu for this sample. The fitting of the experimental grain size data obtained from TEM micrograph to the lognormal distribution function has allowed an estimation of the average grain diameter of 3.7 nm. The surface image of the Fe22Ag78 film observed using a scanning electron microscope showed the presence of droplet like Ag particles on the film surface. The Cu substitution results in smooth films without any Ag particles on the surface. Surface morphology by atomic force microscopy shows that the Fe39Cu13Ag48 film has a surface roughness of 0.75 nm. Finally, we have obtained a maximum giant magnetoresistance ratio of 3.2% in these films measured at 300 K for an in-plane magnetic field of 20 kOe.

scholarly journals Molecular and Structure–Properties Comparison of an Anionically Synthesized Diblock Copolymer of the PS-b-PI Sequence and Its Hydrogenated or Sulfonated Derivatives

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4167
Author(s):  
Nikolaos Politakos ◽  
Ioannis Moutsios ◽  
Gkreti-Maria Manesi ◽  
Konstantinos Artopoiadis ◽  
Konstantina Tsitoni ◽  
...  
Keyword(s):  
Chemical Modification ◽  
Diblock Copolymer ◽  
Film Structure ◽  
X Ray ◽  
Force Microscopy ◽  
Annealing Temperatures ◽  
X Ray Scattering ◽  
Atomic Force ◽  
Poly Ethylene ◽  
Structure Properties

An approach to obtaining various nanostructures utilizing a well-studied polystyrene-b-poly(isoprene) or PS-b-PI diblock copolymer system through chemical modification reactions is reported. The complete hydrogenation and partial sulfonation to the susceptible carbon double bonds of the PI segment led to the preparation of [polystyrene-b-poly(ethylene-alt-propylene)] as well as [polystyrene-b-poly(sulfonated isoprene-co-isoprene)], respectively. The hydrogenation of the polyisoprene block results in enhanced segmental immiscibility, whereas the relative sulfonation induces an amphiphilic character in the final modified material. The successful synthesis of the pristine diblock copolymer through anionic polymerization and the relative chemical modification reactions were verified using several molecular and structural characterization techniques. The thin film structure–properties relationship was investigated using atomic force microscopy under various conditions such as different solvents and annealing temperatures. Small-angle X-ray scattering was employed to identify the different observed nanostructures and their evolution upon thermal annealing.

Blue/White Emission from Hydrogenated Amorphous Silicon Carbide Films Prepared by PECVD

2009 ◽  
Vol 1153 ◽  
Author(s):  
Volodymyr Ivashchenko ◽  
Andrey Vasin ◽  
L. A. Ivashchenko ◽  
P. L. Skrynskyy
Keyword(s):  
Silicon Carbide ◽  
Photoelectron Spectroscopy ◽  
Chemical Vapor ◽  
Substrate Bias ◽  
Double Peak ◽  
Hydrogenated Silicon ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
The One

AbstractPhotoluminescence (PL) from hydrogenated silicon carbide (SiC:H) films is studied at room temperature. The films were deposited by plasma-enhanced chemical vapor (PECVD) technique with and without substrate bias using methyltrichlorosilane as a main precursor. After the deposition the samples were annealed at various temperatures in vacuum. The films were characterized by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The samples deposited without substrate bias (series A) were amorphous, whereas the samples deposited with negative substrate bias -100V (series B) were nanocrystalline. The one-peak (470 nm) and double-peak (415 and 437 nm) PL structures of the as-deposited samples A and B were observed, respectively. Annealing strongly enhanced intensity of PL of the samples B and trandformed PL spectrum from double-peak into broad featureless band with intensity at about 470 nm. The blue PL in as-deposited films B is supposed to be assigned to the radiative recombination in the sites located at the nanocrystallite surface, whereas the photo excitation of carries mostly occurs in nanocrystallite cores. A further increase in annealing temperature causes hydrogen effusion, which leads to an increase of the concentration of non-raidative recombination centers associated with dangling-bonds and as a result, to the quenching of PL.

scholarly journals Pseudomonas aeruginosa Biofilm Removal from Two Kinds of Granite Commonly Found in Catering Kitchen

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Khaddouj Amzil ◽  
Fatima Hamadi ◽  
Hassan Latrache ◽  
Rachida Mimouni ◽  
Hicham Abou Oualid ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Epifluorescence Microscopy ◽  
Plate Count ◽  
X Ray ◽  
Force Microscopy ◽  
Biofilm Removal ◽  
High Roughness ◽  
The One

The biofilm formation on the surfaces which are in direct contact with food products might lead to their contamination and, consequently, present serious health problems for the consumers. The goals of the present work were to study P. aeruginosa biofilm formation on two granites and to investigate the efficiency of sodium hypochlorite (NaCLO) against the same biofilm formed on these substrata using the plate count method (PCM) and epifluorescence microscopy (EP). More biofilm cells adhered to Rosa Porrino than Gris Pinhel, and the PCM method indicated that NaCLO was efficient against the biofilm installed on the Gris Pinhel at the concentration of 1.5% after 15 min of treatment, while it was not efficient against the one installed on the Rosa Porrino. By contrast, the EP showed that the biofilm persists on two granites after NaCLO treatment, at different concentrations and contact times. In addition, the surface properties of granites such as mineral composition, roughness, and physicochemical properties were determined by X-ray diffraction (XRD), scanning electron microscopy coupled with electron diffraction spectroscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared (FTIR), atomic force microscopy (AFM), and contact angle measurement (CAM), respectively. The results revealed that Gris Pinhel is hydrophilic with a high roughness value and Rosa Porrino is hydrophobic with low roughness, while both of them contain the quartz, feldspar, and mica as the main dominant compositions.

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