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Brazilian Dental Journal 2023Radiopaque properties in the infiltrant should be interesting for clinicians to feel more confident to indicate this treatment. Thus, the aim of this study was to...
Radiopaque properties in the infiltrant should be interesting for clinicians to feel more confident to indicate this treatment. Thus, the aim of this study was to evaluate the effect of the incorporation of barium and ytterbium particles on the physical properties of resin infiltrants. Groups were divided according to the addition of ytterbium oxide (Y) alone (30 or 40%) or Y with barium (YB) (15/15% or 20/20% respectively) in the Icon commercial infiltrant and in the experimental infiltrant base. Digital radiography (n=5), Microradiography (n=5), Microtomography (n=3), degree of conversion (n=5), water sorption (n=16), solubility (n=16), contact angle (n=16), flexural strength (n=16), elastic modulus (n=16) and Energy dispersive X-ray Spectroscopy (n=10) were performed. Analyses were performed using the R program, with a significance level of 5%, and microradiography and Microtomography analyses were evaluated qualitatively. In groups with 30 or 40% of ytterbium, radiopacity was higher or equal to enamel. Microradiography and Microtomography appear to have more radiopacity in groups with 40% (Y). Among the groups with no particle addition, those of the experimental infiltrant presented a higher degree of conversion than those of Icon®. In most groups, there was solubility below the ISO-recommended levels. The addition of particles resulted in higher viscosity. Groups with Icon had higher flexural strength and elastic modulus than groups with experimental infiltrant. The addition of 40% (Y) improved polymerization, had low solubility, and had greater radiopacity than enamel, however negatively affected the viscosity increasing then. Experimental groups with the base showed a higher water sorption than Icon groups.
Topics: Composite Resins; Barium; Ytterbium; Polymethacrylic Acids; Materials Testing; Water
PubMed: 37909646
DOI: 10.1590/0103-6440202305379 -
Optics Express Apr 2022A laser system for standoff coherent anti-Stokes Raman scattering (CARS) spectroscopy of various materials under ambient light conditions is presented. The system is...
A laser system for standoff coherent anti-Stokes Raman scattering (CARS) spectroscopy of various materials under ambient light conditions is presented. The system is based on an ytterbium laser and an ultrafast optical parametric amplifier for the generation of a broadband pump tunable from 880 to 930 nm, a Stokes at 1025 nm, and a narrowband probe at 512.5 nm. High-resolution Raman spectra encompassing the fingerprint region (400-1800 cm) are obtained in 5 ms for toluene, and 100 ms for two types of sugars, glucose and fructose, at a distance of 1 m. As a demonstration of the potential of the setup, hyperspectral images of a 2×2-cm target area are collected for a toluene cuvette and a glucose/fructose pressed disk. Our approach is suitable for implementation of a portable system for standoff CARS imaging of chemical and biological materials.
Topics: Fructose; Glucose; Lasers; Spectrum Analysis, Raman; Toluene; Ytterbium
PubMed: 35473258
DOI: 10.1364/OE.457373 -
RSC Advances Jun 2020To determine the chemotherapeutic and pharmacokinetic aspects of an ytterbium complex containing 2,9-dimethyl-1,10-phenanthroline (MePhen), binding studies were carried...
To determine the chemotherapeutic and pharmacokinetic aspects of an ytterbium complex containing 2,9-dimethyl-1,10-phenanthroline (MePhen), binding studies were carried out with FS-DNA/BSA by employing multiple biophysical methods and a molecular modeling study. There are different techniques including absorption spectroscopy, fluorescence spectroscopy, circular dichroism studies, viscosity experiments (only in the case of DNA), and competitive experiments used to determine the interaction mode between DNA/BSA and the ytterbium-complex. The results showed that the Yb-complex exhibited a high propensity for the interaction of BSA and DNA hydrophobic interactions and van der Waals forces. Further, a competitive examination and docking study showed that the interaction site of the ytterbium complex on BSA is site III. The results of docking calculations for DNA/BSA were in good agreement with experimental findings. The complex displays efficient DNA cleavage in the presence of hydrogen peroxide. Moreover, antimicrobial studies of different bacteria and fungi indicated its promising antibacterial activity. cytotoxicity studies of the Yb-complex, starch nano-encapsulated, and lipid nano-encapsulated were carried out in MCF-7 and A-549 cell lines, which revealed significantly good activity. The results of anticancer activity studies showed that the cytotoxic activity of the Yb-complex was increased when encapsulated with nanocarriers. Based on biological applications of the Yb-complex, it can be concluded that this complex and its nanocarriers can act as novel anticancer and antimicrobial candidates.
PubMed: 35520322
DOI: 10.1039/d0ra03895d -
ACS Applied Materials & Interfaces Aug 2022Significant work has been done to develop nanoparticle contrast agents for computed tomography (CT), with a focus on identifying safer and more effective formulations....
Significant work has been done to develop nanoparticle contrast agents for computed tomography (CT), with a focus on identifying safer and more effective formulations. Contrast agents for spectral photon-counting computed tomography (SPCCT), a fast-growing imaging modality derived from conventional CT, have also recently gained considerable attention. In this study, we explored the synthesis of ultrasmall ytterbium nanoparticles (YbNP) and demonstrated that, potentially, they can be used as conventional CT and SPCCT contrast agents. These nanoparticles were tested for their cytotoxicity and contrast-generating properties with a variety of imaging systems. When scanned with conventional CT and SPCCT at clinically relevant energies, YbNP are significantly more attenuating than gold nanoparticles (AuNP), the contrast agents that have been most well studied. Furthermore, YbNP were studied for their potential application for labeling and monitoring hydrogels. The presence of the YbNP payload in hydrogels allowed for hydrogel localization and tracking . Additionally, the imaging results revealed that YbNP generate higher contrast when compared to AuNP used as a label. In summary, this is the first research study to examine ultrasmall YbNP as conventional CT and SPCCT contrast agents, as well as using them in a hydrogel system to make it radiopaque. These findings underscore YbNP's utility as CT and SPCCT contrast agents, as well as their potential for tracking hydrogels .
Topics: Contrast Media; Gold; Hydrogels; Metal Nanoparticles; Phantoms, Imaging; Photons; Tomography, X-Ray Computed; Ytterbium
PubMed: 35975982
DOI: 10.1021/acsami.2c12354 -
Nanomaterials (Basel, Switzerland) Feb 2023Lead-halide perovskite nanocrystals are an attractive class of materials since they can be easily fabricated, their optical properties can be tuned all over the visible... (Review)
Review
Lead-halide perovskite nanocrystals are an attractive class of materials since they can be easily fabricated, their optical properties can be tuned all over the visible spectral range, and they possess high emission quantum yields and narrow photoluminescence linewidths. Doping perovskites with lanthanides is one of the ways to widen the spectral range of their emission, making them attractive for further applications. Herein, we summarize the recent progress in the synthesis of ytterbium-doped perovskite nanocrystals in terms of the varying synthesis parameters such as temperature, ligand molar ratio, ytterbium precursor type, and dopant content. We further consider the dependence of morphology (size and ytterbium content) and optical parameters (photoluminescence quantum yield in visible and near-infrared spectral ranges) on the synthesis parameters. The developed open-source code approximates those dependencies as multiple-parameter linear regression and allows us to estimate the value of the photoluminescence quantum yield from the parameters of the perovskite synthesis. Further use and promotion of an open-source database will expand the possibilities of the developed code to predict the synthesis protocols for doped perovskite nanocrystals.
PubMed: 36839112
DOI: 10.3390/nano13040744 -
Chemical Science Oct 2020Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized by the reduction of their trivalent halide precursors with potassium graphite in the presence...
Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized by the reduction of their trivalent halide precursors with potassium graphite in the presence of biphenyl. While the samarium complex had a similar structure as previously reported rare earth metal biphenyl complexes, with the two samarium ions bound to the same phenyl ring, the ytterbium counterpart adopted a different structure, with the two ytterbium ions bound to different phenyl rings. Upon the addition of crown ether to encapsulate the potassium ions, the inverse-sandwich samarium biphenyl structure remained intact; however, the ytterbium biphenyl structure fell apart with the concomitant formation of a divalent ytterbium crown ether complex and potassium biphenylide. Spectroscopic and computational studies were performed to gain insight into the electronic structures and bonding interactions of these samarium and ytterbium biphenyl complexes. While the ytterbium ions were found to be divalent with a 4f electron configuration and form a primarily ionic bonding interaction with biphenyl dianion, the samarium ions were in the trivalent state with a 4f electron configuration and mainly utilized the 5d orbitals to form a δ-type bonding interaction with the π* orbitals of the biphenyl tetraanion, showing covalent character.
PubMed: 34168742
DOI: 10.1039/d0sc03555f -
Scientific Reports Jul 2022Hydrophilic photocatalytically active ZnO and ZnO thin films doped with YbO and EuO (rare earth metal oxide, REM) with optical transmittance exceeding 76% in the visible...
Hydrophilic photocatalytically active ZnO and ZnO thin films doped with YbO and EuO (rare earth metal oxide, REM) with optical transmittance exceeding 76% in the visible light range (λ = 550 nm) were prepared by a combination of sol-gel technique, spin-coating and high temperature thermal treatment at 500 and 600 °C. The thin films were tested using advanced research methods, i.e.: morphology and topography and fractures along with approximate thickness values were investigated on scanning electron microscope (SEM), chemical composition was determined using X-ray Energy Dispersive Spectroscopy (X-ray Energy Spectroscopy), topography and roughness were measured on atomic force microscope (AFM), water contact angle values were determined by sitting water droplet method, optical properties of the fabricated materials were investigated using UV/Vis spectrophotometer. The decolorization efficiency of rhodamine B in aqueous solution was analyzed over a period of 190 min, obtaining degradation rates of: 54.7% and 43.1%, for ZnO and ZnO coatings doped with ytterbium oxide and europium oxide, respectively. The roughness of thin hybrid coatings did not exceed 50 nm, ensuring effective absorption of electromagnetic radiation by the layers. The methodology presented by the authors for the fabrication of thin hybrid films characterized by the key properties of self-cleaning coatings can be successfully applied to coatings of photovoltaic panels and architectural glass structures.
PubMed: 35790837
DOI: 10.1038/s41598-022-14899-z -
Turkish Journal of Chemistry 2022Metal oxide nanomaterials are widely used in many applications of renewable energy. Ytterbium oxide (YbO) also attracts attention due to its similar structure to ZnO...
Metal oxide nanomaterials are widely used in many applications of renewable energy. Ytterbium oxide (YbO) also attracts attention due to its similar structure to ZnO (~3,26 eV) and TiO (~3,36 eV) in terms of bandgap energy. In this study, YbO belonging to the lanthanide oxide family was produced as nanofiber forms by using the electrospinning technique, which allows for large-scale production, for the first time. The morphological, structural, optical, and phase properties of the produced nanofibers were investigated via XRD, SEM-Mapping, TEM, FTIR, UV-Vis, and XPS characterization techniques. As a result of these analyses, it was determined that the YbO nanofibers with a diameter of 125 ± 15 nm have a cubic crystal structure and a bandgap of 3.32 eV. The results of this study have shown that the YbO nanofibers are capable of performing performance evaluations in many different energy conversion applications and others.
PubMed: 37529746
DOI: 10.55730/1300-0527.3472 -
Journal of Nuclear Medicine : Official... Jan 1976A source of error in cerebrospinal fluid (CSF) infusion tests is leakage at the dural puncture site. The addition of a bolus of radionuclide to the infusion fluid was...
A source of error in cerebrospinal fluid (CSF) infusion tests is leakage at the dural puncture site. The addition of a bolus of radionuclide to the infusion fluid was helpful in detecting the existence of leakage as shown by increased infusion pressure in six of eight patients studied with and without scintigraphic evidence of leakage. Comparison of CSF dynamics in 26 patients studied by infusion cisternography and conventional cisternography showed similar patterns, suggesting no alteration of CSF dynamics by the artificial CSF infusion. Combining the two tests, therefore, resulted in simple identification of the leakage and saved the patient time and discomfort.
Topics: Cisterna Magna; Humans; Hydrocephalus; Pentetic Acid; Radionuclide Imaging; Ytterbium
PubMed: 1244453
DOI: No ID Found -
Dalton Transactions (Cambridge, England... Oct 2021The syntheses of the ytterbium(II) distannyl [Yb{Sn(SiMe)}·(thf)] (Yb-Sn) and of its digermyl analogue [Yb{Ge(SiMe)}·(thf)] (Yb-Ge) are presented. The compounds were...
The syntheses of the ytterbium(II) distannyl [Yb{Sn(SiMe)}·(thf)] (Yb-Sn) and of its digermyl analogue [Yb{Ge(SiMe)}·(thf)] (Yb-Ge) are presented. The compounds were characterised by multinuclear high-resolution solution NMR spectroscopy, including Yb NMR, and by X-ray diffraction crystallography. The bonding and electronic properties of the two complexes, along with those of the known ytterbium(II) disilyl derivative [Yb{Si(SiMe)}·(thf)] (Yb-Si) and those of the congeneric calcium distannyl [Ca{Sn(SiMe)}·(thf)] (Ca-Sn), were investigated in detail by DFT calculations. This analysis points at a primarily ionic Yb-tetrel bonding, with a small covalent contribution, attributed principally to the 5d(Yb) participation. This weak covalent character is found to be larger for the distannyl Yb-Sn than for its lighter Si- and Ge-derivatives. The covalent component is also found to be greater in Yb-Sn than in Ca-Sn, due to the availability of the 5d(Yb) orbitals for bonding.
PubMed: 34553734
DOI: 10.1039/d1dt02355a