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1.
ACS Sens ; 9(8): 3947-3957, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39046188

RESUMEN

In recent years, flexible and stretchable strain sensors have emerged as a prominent area of research, primarily due to their remarkable stretchability and extremely low strain detection threshold. Nevertheless, the advancement of sensors is currently constrained by issues such as complexity, high costs, and limited durability. To tackle the aforementioned issues, this study introduces a lepidophyte-inspired flexible, stretchable strain sensor (LIFSSS). The stretchable bioelectronics composites were composed of multiwalled carbon nanotubes, graphene, neodymium iron boron, and polydimethylsiloxane. Unique biolepidophyted microstructures and magnetic conductive nanocomposites interact with each other through synergistic interactions, resulting in the effective detection of tensile strain and magnetic excitation. The LIFSSS exhibits a 170% tensile range, a linearity of 0.99 in 50-170% strain (0.96 for full-scale range), and a fine durability of 7000 cycles at 110% tensile range. The sensor accurately detects variations in linear tensile force, human movement, and microexpressions. Moreover, LIFSSS demonstrates enhanced efficacy in sign language recognition for individuals with hearing impairments and magnetic grasping for robotic manipulators. Hence, the LIFSSS proposed in this study shows potential applications in various fields, including bioelectronics, electronic skin, and physiological activity monitoring.


Asunto(s)
Dimetilpolisiloxanos , Grafito , Nanocompuestos , Nanotubos de Carbono , Dispositivos Electrónicos Vestibles , Nanocompuestos/química , Nanotubos de Carbono/química , Humanos , Dimetilpolisiloxanos/química , Grafito/química , Neodimio/química , Resistencia a la Tracción , Técnicas Biosensibles/métodos , Fenómenos Biomecánicos
2.
Luminescence ; 39(7): e4836, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023133

RESUMEN

The near-infrared (NIR) down-conversion process for broadband sensitization has been studied in Eu2+-Nd3+ co-doped BaAl2O4. This material has a broad absorption band of 200-480 nm and can convert photons in the visible region into NIR photons. The NIR emission at 1064 nm, attributed to the Nd3+:4F3/2 → 4I11/2 transition, matches the bandgap of Si, allowing Si solar cells to utilize the solar spectrum better. The energy transfer (ET) process between Eu2+ and Nd3+ was demonstrated using photoluminescence spectra and luminescence decay curves, and Eu2+ may transfer energy to Nd3+ through the cooperative energy transfer (CET) to achieve the down-conversion process. The energy transfer efficiency (ETE) and theoretical quantum efficiency (QE) were 68.61% and 156.34%, respectively, when 4 mol% Nd3+ was introduced. The results indicate that BaAl2O4:Eu2+-Nd3+ can serve as a potential modulator of the solar spectrum and is expected to be applied to Si solar cells.


Asunto(s)
Europio , Rayos Infrarrojos , Neodimio , Silicio , Energía Solar , Europio/química , Silicio/química , Neodimio/química , Luminiscencia , Transferencia de Energía , Bario/química , Mediciones Luminiscentes
3.
Luminescence ; 39(7): e4832, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39031322

RESUMEN

The aim of this research is to investigate novel compositions of oxyfluoride glasses doped with Neodymium (Nd3+) rare earth ions in the visible spectrum. This area has not been extensively studied in the existing literature, so it is vital to understand the favorable photoluminescence characteristics within this part of the electromagnetic spectrum. Therefore, we synthesized and characterized SiO2-PbO-PbF2 (SPF) doped with 1% neodymium (Nd3+) ions glasses. Spectroscopic analyses, based on Judd-Ofelt theory, were conducted on absorption spectra. These analyses enabled to determine absorption cross-sections, transition probabilities, and Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 for the different transition. Additionally, we calculated various radiative properties, such as branching ratios, integrated cross-sections, radiative lifetimes, emission cross-section, optical gain, and the multicolor behavior (chromaticity coordinates, CIE diagram) under different excitation wavelengths. The results suggest promising prospects for using these oxyfluoride silicate glasses doped with Nd3+ as a fluorophore, potentially for lasing materials around 630-nm emission and in other photonic applications.


Asunto(s)
Vidrio , Neodimio , Silicatos , Dióxido de Silicio , Neodimio/química , Vidrio/química , Silicatos/química , Dióxido de Silicio/química , Fluoruros/química , Plomo/química , Óxidos/química , Fenómenos Ópticos , Luminiscencia , Color
4.
Nat Commun ; 15(1): 5876, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997277

RESUMEN

Biological ion channels exhibit high selectivity and permeability of ions because of their asymmetrical pore structures and surface chemistries. Here, we demonstrate a biomimetic nanofluidic channel (BNC) with an asymmetrical structure and glycyl-L-proline (GLP) -functionalization for ultrafast, selective, and unidirectional Dy3+ extraction over other lanthanide (Ln3+) ions with very similar electronic configurations. The selective extraction mainly depends on the amplified chemical affinity differences between the Ln3+ ions and GLPs in nanoconfinement. In particular, the conductivities of Ln3+ ions across the BNC even reach up to two orders of magnitude higher than in a bulk solution, and a high Dy3+/Nd3+ selectivity of approximately 60 could be achieved. The designed BNC can effectively extract Dy3+ ions with ultralow concentrations and thereby purify Nd3+ ions to an ultimate content of 99.8 wt.%, which contribute to the recycling of rare earth resources and environmental protection. Theoretical simulations reveal that the BNC preferentially binds to Dy3+ ion due to its highest affinity among Ln3+ ions in nanoconfinement, which attributes to the coupling of ion radius and coordination matching. These findings suggest that BNC-based ion selectivity system provides alternative routes to achieving highly efficient lanthanide separation.


Asunto(s)
Disprosio , Disprosio/química , Iones , Biomimética/métodos , Nanotecnología/métodos , Neodimio/química
5.
J Chromatogr A ; 1729: 465033, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38852269

RESUMEN

Efficient rare earth element (REE) separations are becoming increasingly important to technologies ranging from renewable energy and high-performance magnets to applied radioisotope separations. These separations are made challenging by the extremely similar chemical and physical characteristics of the individual elements, which almost always occupy the 3+ oxidation state under ambient conditions. Herein, we discuss the development of a novel REE separation aimed at obtaining purified samples of neodymium (Nd) on a multi-milligram scale using high-speed counter-current chromatography (HSCCC). The method takes advantage of the subtle differences in ionic radii between neighboring REEs to tune elution rates in dilute acid through implementation of the di-(2-ethylhexyl)phosphoric acid (HDEHP)-infused stationary phase (SP) of the column. A La/Ce/Nd/Sm separation was demonstrated at a significantly higher metal loading than previously accomplished by HSCCC (15 mg, RNd/REE > 0.85), while the Pr/Nd separation was achieved at lower metal loadings (0.3 mg, RNd/Pr = 0.75 - 0.83). The challenges associated with scaling REE separations via HSCCC are presented and discussed within.


Asunto(s)
Distribución en Contracorriente , Neodimio , Distribución en Contracorriente/métodos , Neodimio/química , Neodimio/aislamiento & purificación , Organofosfatos
6.
ACS Appl Bio Mater ; 7(6): 3821-3827, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38787698

RESUMEN

Near-infrared fluorescence (NIRF) thermometry is an emerging method for the noncontact measurement of in vivo deep temperatures. Fluorescence-lifetime-based methods are effective because they are unaffected by optical loss due to excitation or detection paths. Moreover, the physiological changes in body temperature in deep tissues and their pharmacological effects are yet to be fully explored. In this study, we investigated the potential application of the NIRF lifetime-based method for temperature measurement of in vivo deep tissues in the abdomen using rare-earth-based particle materials. ß-NaYF4 particles codoped with Nd3+ and Yb3+ (excitation: 808 nm, emission: 980 nm) were used as NIRF thermometers, and their fluorescence decay curves were exponential. Slope linearity analysis (SLA), a screening method, was proposed to extract pixels with valid data. This method involves performing a linearity evaluation of the semilogarithmic plot of the decay curve collected at three delay times after cutting off the pulsed laser irradiation. After intragastric administration of the thermometer, the stomach temperature was monitored by using an NIRF time-gated imaging setup. Concurrently, a heater was attached to the lower abdomens of the mice under anesthesia. A decrease in the stomach temperature under anesthesia and its recovery via the heater indicated changes in the fluorescence lifetime of the thermometer placed inside the body. Thus, NaYF4:Nd3+/Yb3+ functions as a fluorescence thermometer that can measure in vivo temperature based on the temperature dependence of the fluorescence lifetime at 980 nm under 808 nm excitation. This study demonstrated the ability of a rare-earth-based NIRF thermometer to measure deep tissues in live mice, with the proposed SLA method for excluding the noisy deviations from the analysis for measuring temperature using the NIRF lifetime of a rare-earth-based thermometer.


Asunto(s)
Fluoruros , Imagen Óptica , Iterbio , Itrio , Animales , Ratones , Itrio/química , Iterbio/química , Fluoruros/química , Neodimio/química , Materiales Biocompatibles/química , Ensayo de Materiales , Tamaño de la Partícula , Temperatura , Termometría/métodos , Rayos Infrarrojos
7.
Sci Rep ; 14(1): 9877, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38684756

RESUMEN

Our study focused on the optical behavior, methylene blue (MB) dye degradation potential, antibacterial performance, and silver and trioxide mineral interaction with different bacterial species. We found that the addition of silver nanoparticles (Ag NPs) to neodymium oxide (Nd2O3) resulted in a significant response, with an enlargement of the inhibition zone for bacterial species such as Staphylococcus aureus and Escherichia coli. Specifically, the inhibition zone for S. aureus increased from 9.3 ± 0.5 mm for pure Nd2O3 to 16.7 ± 0.4 mm for the Ag/Nd2O3 nano-composite, while for E. coli, it increased from 8.8 ± 0.4 mm for Nd2O3 to 15.9 ± 0.3 mm for Ag/Nd2O3. Furthermore, the optical behavior of the composites showed a clear band-gap narrowing with the addition of Ag NPs, resulting in enhanced electronic localization. The direct and indirect transitions reduced from 6.7 to 6.1 eV and from 5.2 to 2.9 eV, respectively. Overall, these results suggest that the Ag/Nd2O3 nano-composite has potential applications in sensor industries and water treatment, thanks to its enhanced optical behavior, antibacterial performance, and efficient MB degradation capabilities. In terms of MB degradation, the Ag/Nd2O3 mixed system exhibited more efficient degradation compared to pure Nd2O3. After 150 min, the MB concentration in the mixed system decreased to almost half of its starting point, while pure Nd2O3 only reached 33%.


Asunto(s)
Antibacterianos , Escherichia coli , Nanopartículas del Metal , Azul de Metileno , Neodimio , Óxidos , Plata , Staphylococcus aureus , Azul de Metileno/química , Nanopartículas del Metal/química , Plata/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Neodimio/química , Óxidos/química , Adsorción
8.
Environ Pollut ; 349: 123978, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38615839

RESUMEN

Sustainable technologies for the recovery of rare earth elements (REE) from waste need to be developed to decrease the volume of ore mining extractions and its negative environmental consequences, while simultaneously restoring previously impacted lands. This is critical due to the extensive application of REE in everyday life from electronic devices to energy and medical technologies, and the dispersed distribution of REE resources in the world. REE recovery by plants has been previously studied but the feasibility of REE phytoextraction from a poorly soluble solid phase (i.e., nanoparticles) by different plant species has been rarely investigated. In this study, the effect of biostimulation and bioaugmentation on phytorecovery of REE nanoparticles (REE-NP) was investigated by exposing ryegrass seeds to REE-NP in hydroponic environments. This was studied in two sets of experiments: bioaugmentation (using CeO2 nanoparticles and Methylobacterium extorquens AM1 pure culture), and biostimulation (using CeO2 or Nd2O3 nanoparticles and endogenous microorganisms). Addition of M. extorquens AM1 in bioaugmentation experiment including 500 mg/L CeO2 nanoparticles could not promote the nanoparticles accumulation in both natural and surface-sterilized treatments. However, it enhanced the translocation of Ce from roots to shoots in sterile samples. Moreover, another REE-utilizing bacterium, Bacillus subtilis, was enriched more than M. extorquens in control samples (no M. extorquens AM1), and associated with 52% and 14% higher Ce extraction in both natural (165 µg/gdried-plant) and surface-sterilized samples (136 µg/gdried-plant), respectively; showing the superior effect of endogenous microorganisms' enrichment over bioaugmentation in this experiment. In the biostimulation experiments, up to 705 µg/gdried-plant Ce and 19,641 µg/gdried-plant Nd could be extracted when 500 mg/L REE-NP were added. Furthermore, SEM-EDS analysis of the surface and longitudinal cross-sections of roots in Nd2O3 treatments confirmed surface and intracellular accumulation of Nd2O3-NP. These results demonstrate stimulation of endogenous microbial community can lead to an enhanced REE phytoaccumulation.


Asunto(s)
Biodegradación Ambiental , Cerio , Hidroponía , Lolium , Cerio/química , Cerio/metabolismo , Lolium/metabolismo , Neodimio/química , Óxidos/química , Contaminantes del Suelo/metabolismo , Nanopartículas/química
9.
Luminescence ; 39(5): e4754, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38679894

RESUMEN

Near-infrared mechanoluminescence is a phenomenon that produces high penetrating near-infrared light under external stimulation. Near-infrared light coincides with the biological window, lower optical loss, and the fact that the mechanoluminescence material is a medium that converts mechanical energy into light energy. The near-infrared mechanoluminescence material has potential application prospects in the fields of biological imaging, medical diagnosis, and monitoring of building materials. In this article, we report on a perovskite-type Sr3Sn2O7:Nd3+ near-infrared mechanoluminescence material, and its peaks locate in the first near-infrared window (800-1000 nm) and the second near-infrared window (1080, 1350 nm), respectively. Under the condition of pre-sintering with Li2CO3 as flux, the best sintering conditions are obtained, and the luminescence of material is in perfect agreement with the applied mechanical stress. In addition, a near-infrared mechanoluminescence sensor is proposed to solve the problem of building damage and timely maintenance.


Asunto(s)
Rayos Infrarrojos , Mediciones Luminiscentes , Titanio , Luminiscencia , Óxidos/química , Estroncio/química , Neodimio/química , Compuestos de Calcio/química
10.
Small ; 20(25): e2310180, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38342676

RESUMEN

Knee replacement surgery confronts challenges including patient dissatisfaction and the necessity for secondary procedures. A key requirement lies in dual-modal measurement of force and temperature of artificial joints during postoperative monitoring. Here, a novel non-toxic near-infrared (NIR) phosphor Sr3Sn2O7:Nd, Yb, is designed to realize the dual-modal measurement. The strategy is to entail phonon-assisted upconversion luminescence (UCL) and trap-controlled mechanoluminescence (ML) in a single phosphor well within the NIR biological transmission window. The phosphor is embedded in medical bone cement forming a smart joint in total knee replacements illustrated as a proof-of-concept. The sensing device can be charged in vitro by a commercial X-ray source with a safe dose rate for ML, and excited by a low power 980 nm laser for UCL. It attains impressive force and temperature sensing capabilities, exhibiting a force resolution of 0.5% per 10 N, force detection threshold of 15 N, and a relative temperature sensitive of up to 1.3% K-1 at 309 K. The stability against humidity and thermal shock together with the robustness of the device are attested. This work introduces a novel methodological paradigm, paving the way for innovative research to enhance the functionality of artificial tissues and joints in living organisms.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Temperatura , Humanos , Estroncio/química , Iterbio/química , Luminiscencia , Neodimio/química , Mediciones Luminiscentes/métodos , Rayos Infrarrojos
11.
Rev. ADM ; 57(4): 137-42, jul.-ago. 2000. ilus
Artículo en Español | LILACS | ID: lil-278271

RESUMEN

El uso del rayo láser en odontología inició en la década de ;ps 80, principalmente el CO2 y el Nd/YAG (Neodimium/Ytrium-Aluminium-Garnet); su principal uso es en los tejidos blandos en la cavidad bucal, por ejemplo en tratamientos periodontales, en excisión de fibromas, etc., así como también el Er/YAG que se utiliza hoy en día para remover caries y perforar estructura dentaria. El uso de láser en odontología tiene sus limitaciones, ventajas y desventajas, así como cualquier otra técnica quirúrgica/operatoria. El entendimiento de las bases de la óptica láser y las reacciones de los tejidos son esenciales. Aún así el operador debe tener conocimiento de las diferentes aplicaciones para tratamiento


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Dióxido de Carbono/química , Mucosa Bucal/efectos de la radiación , Rayos Láser/normas , Rayos Láser/uso terapéutico , Diente/efectos de la radiación , Aluminio/química , Caries Dental/terapia , Erbio/química , Gingivectomía/métodos , Hemostasis/fisiología , Implantación Dental Endoósea/normas , Frenillo Lingual/cirugía , Microabrasión del Esmalte/métodos , Neodimio/química , Preparación de la Cavidad Dental/métodos , Protección Radiológica/métodos , Itrio/química
12.
Rev. Soc. Odontol. La Plata ; 13(25): 18-21, abr. 2000. ilus
Artículo en Español | LILACS | ID: lil-268020

RESUMEN

Este trabajo tiene la finalidad de promover el conocimiento del uso del láser en periodoncia, sus propiedades físicas, tipos de rayos láser actualmente disponibles y sus efectos de accón sobre tejidos orales y posibilidades de aplicación clínica. Los rayos láser más usados en odontología son el de dióxido de carbono (CO2) y el de neodymium:yttrium-aluminium-garnet (Nd:YAG), para una amplia variedad de procedimientos quirúrgicos, control de la microflora subgingival sobre la superficie radicular, donde se demostró efectos significativos


Asunto(s)
Dióxido de Carbono/química , Periodoncia/instrumentación , Rayos Láser/uso terapéutico , Itrio/química , Aluminio/química , Biopsia , Alargamiento de Corona/instrumentación , Coagulación con Láser/métodos , Encía/efectos de la radiación , Gingivectomía/métodos , Neodimio/química , Bolsa Periodontal , Periodoncio/efectos de la radiación , Raíz del Diente/efectos de la radiación
13.
Rev. Soc. Odontol. Plata ; 13(25): 18-21, abr. 2000. ilus
Artículo en Español | BINACIS | ID: bin-11983

RESUMEN

Este trabajo tiene la finalidad de promover el conocimiento del uso del láser en periodoncia, sus propiedades físicas, tipos de rayos láser actualmente disponibles y sus efectos de accón sobre tejidos orales y posibilidades de aplicación clínica. Los rayos láser más usados en odontología son el de dióxido de carbono (CO2) y el de neodymium:yttrium-aluminium-garnet (Nd:YAG), para una amplia variedad de procedimientos quirúrgicos, control de la microflora subgingival sobre la superficie radicular, donde se demostró efectos significativos (AU)


Asunto(s)
Rayos Láser/uso terapéutico , Periodoncia/instrumentación , Dióxido de Carbono/química , Itrio/química , Neodimio/química , Aluminio/química , Raíz del Diente/efectos de la radiación , Encía/efectos de la radiación , Periodoncio/efectos de la radiación , Gingivectomía/métodos , Coagulación con Láser/métodos , Alargamiento de Corona/instrumentación , Biopsia/métodos , Bolsa Periodontal
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