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1.
Small ; : e2402896, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898745

RESUMEN

Developing high-performance and stable Sn-based perovskite solar cells (PSCs) is difficult due to the inherent tendency of Sn2+ oxidation and, the huge energy mismatch between perovskite and Phenyl-C61-butyric acid methyl ester (PCBM), a frequently employed electron transport layer (ETL). This study demonstrates that perovskite surface defects can be passivated and PCBM's electrical properties improved by doping n-type polymer N2200 into PCBM. The doping of PCBM with N2200 results in enhanced band alignment and improved electrical properties of PCBM. The presence of electron-donating atoms such as S, and O in N2200, effectively coordinates with free Sn2+ to prevent further oxidation. The doping of PCBM with N2200 offers a reduced conduction band offset (from 0.38 to 0.21 eV) at the interface between the ETL and perovskite. As a result, the N2200 doped PCBM-based PSCs show an enhanced open circuit voltage of 0.79 V with impressive power conversion efficiency (PCE) of 12.98% (certified PCE 11.95%). Significantly, the N2200 doped PCBM-based PSCs exhibited exceptional stability and retained above 90% of their initial PCE when subjected to continuous illumination at maximum power point tracking for 1000 h under one sun.

2.
Eur J Nucl Med Mol Imaging ; 51(7): 2124-2133, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38285206

RESUMEN

PURPOSE: This paper discusses the optimization of pharmacokinetic modelling and alternate simplified quantification method for [18F]AlF-P16-093, a novel tracer for in vivo imaging of prostate cancer. METHODS: Dynamic PET/CT scans were conducted on eight primary prostate cancer patients, followed by a whole-body scan at 60 min post-injection. Time-activity curves (TACs) were obtained by drawing volumes of interest for primary prostatic and metastatic lesions. Optimal kinetic modelling involved evaluating three compartmental models (1T2K, 2T3K, and 2T4K) accounting for fractional blood volume (Vb). The simplified quantification method was then determined based on the correlation between the static uptake measure and total distribution volume (Vt) obtained from the optimal pharmacokinetic analysis. RESULTS: In total, 17 intraprostatic lesions, 10 lymph nodes, and 36 osseous metastases were evaluated. Visually, the contrast of the tumor increased and showed the steepest incline within the first few minutes, whereas background activity decreased over time. Full pharmacokinetic analysis revealed that a reversible two-compartmental (2T4K) model is the preferred kinetic model for the given tracer. The kinetic parameters K1, k3, Vb, and Vt were all significantly higher in lesions when compared with normal tissue (P < 0.01). Several simplified protocols were tested for approximating comprehensive dynamic quantification in tumors, with image-based SURmean (the ratio of tumor SUVmean to blood SUVmean) within the 28-34 min window found to be sufficient for approximating the total distribution Vt values (R2 = 0.949, P < 0.01). Both Vt and SURmean correlated significantly with the total serum prostate-specific antigen (tPSA) levels (P < 0.01). CONCLUSIONS: This study introduced an optimized pharmacokinetic modelling approach and a simplified acquisition method for [18F]AlF-P16-093, a novel PSMA-targeted radioligand, highlighting the feasibility of utilizing one static PET imaging (between 30 and 60 min) for the diagnosis of prostate cancer. Note that the image-derived input function in this study may not reflect the true corrected plasma input function, therefore the interpretation of the associated kinetic parameter estimates should be done with caution.


Asunto(s)
Modelos Biológicos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/metabolismo , Anciano , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Persona de Mediana Edad , Radiofármacos/farmacocinética , Cinética , Lisina/análogos & derivados , Urea/análogos & derivados
3.
Inorg Chem ; 63(35): 16206-16216, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39168940

RESUMEN

Preparing chiral plasmonic nanoparticles (NPs) with strong chiroptical responses is crucial in numerous fields including constructing optical materials, chiral sensing, and chiral-dependent biological processes. However, precise regulation over the chiral optical activity and chiral configuration of plasmonic NPs is still a challenge. In this work, we report Au helicoid NPs with different chiral structures and reversal chirality directed by the oligomeric structure of inducer glutathione (GSH). By precisely controlling the oligomeric structure of GSH and other synthetic parameters, we successfully prepared chiral Au helicoid NPs with a high anisotropy factor of 0.03. The obtained chiral Au NPs demonstrated an excellent performance in discriminating penicillamine (Pen) enantiomers. Our findings provide a construction strategy for chiral Au NPs and contribute insight into the regulation effect of chiral inducers on the growth of chiral metal NPs.


Asunto(s)
Glutatión , Oro , Nanopartículas del Metal , Penicilamina , Oro/química , Penicilamina/química , Nanopartículas del Metal/química , Estereoisomerismo , Glutatión/química , Estructura Molecular , Tamaño de la Partícula
4.
Inorg Chem ; 62(46): 19087-19095, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37934916

RESUMEN

Triplet energy transfer (TET) from semiconductor quantum dots (QDs) is an emerging strategy for sensitizing molecular triplets that have great potential in many applications. Here, CdSe QDs with varying sizes and 1-pyrenecarboxylic acid (PCA) are selected as the triplet donor and acceptor, respectively, to study the TET and charge transfer dynamics as well as enhanced singlet oxygen (1O2) generation properties. The results from static and transient spectroscopy measurements demonstrate that both the TET and hole transfer occur at the QDs-PCA interface. The observed significant drop in TET efficiency from 52 to 8% with increasing QD size results from the reduced TET driving force between the QDs and PCA, which is further confirmed by the more efficient sensitization of the anthracene derivative with a large TET driving force. In contrast, the hole transfer efficiency displays a small decrease with an increasing QD size due to a slight change in the hole driving force. The sensitized PCA triplets show a good ability of 1O2 generation, and the 1O2 formation rate increases 10-fold as the QD size decreases from 3.3 to 2.4 nm. These findings provide a profound understanding of the TET and hole transfer mechanism from QDs to molecules and are significant in designing efficient 1O2 generation systems based on semiconductor QDs and triplet molecules.

5.
Phys Chem Chem Phys ; 25(12): 8913-8920, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36916640

RESUMEN

Triplet energy transfer (TET) from semiconductor quantum dots (QDs) to molecular triplets has potential applications in photon up-conversion and singlet oxygen generation. Here, we have constructed a complex consisting of CdTe QDs as the donor and 9-anthracenecarboxylic acid (ACA) as the triplet acceptor, and studied the TET pathways and enhanced singlet oxygen generation properties. The results from steady-state and time-resolved spectroscopy demonstrate efficient TET with a total efficiency of over 80% from photoexcited CdTe QDs to ACA. Dynamical analysis clearly indicates two distinctive TET channels - hot electron exchange and thermalized electron exchange - mediating the TET process in the CdTe QDs-ACA complex. The TET efficiencies from hot electron exchange at high energetic levels and thermalized electron exchange on the lowest exciton state can reach ∼27% and ∼85%, respectively, following 530 nm excitation. This efficient TET endows the CdTe QDs-ACA complex with a good capability of generating singlet oxygen species with a yield of up to ∼59%. These findings contribute further insights to the mechanisms of interfacial TET processes and are significant in designing efficient TET systems based on semiconductor nanoparticles and triplet molecules.

6.
Angew Chem Int Ed Engl ; 62(13): e202300158, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36740576

RESUMEN

Fast and continuous ion insertion is blocked in the common electrodes operating with widely accepted single-ion storage mechanism, primarily due to Coulomb repulsion between the same ions. It results in an irreconcilable conflict between capacity and rate performance. Herein, we designed a porous organic framework with novel multiple-ion co-storage modes, including PF6 - /Li+ , OTF- /Mg2+ , and OTF- /Zn2+ co-storage. The Coulomb interactions between cationic and anionic carriers in the framework can significantly promote electrode kinetics, by rejuvenating fast ion carrier migration toward framework interior. Consequently, the framework via PF6 - /Li+ co-storage mode shows a high energy density of 878 Wh kg-1 cycled more than 20 000 cycles, with an excellent power density of 28 kW kg-1 that is already comparable to commercial supercapacitors. The both greatly improved energy and power densities via the co-storage mode may pave a way for exploring new electrodes that are not available from common single-ion electrodes.

7.
Opt Express ; 29(4): 5213-5225, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726061

RESUMEN

Graphene-based materials have been attracted many attentions due to their excellent properties and potential applications in many fields. Graphene also provides a flexible substrate to develop novel functional materials by hybridizing with other organic or inorganic components. Herein, we report the functionalization of reduced graphene oxide (RGO) with an azobenzene derivative (BNB-t8) containing the π-conjugated moiety and hydrogen bonding groups, to improve the optical and nonlinear optical properties of RGO. With the introducing of BNB-t8, a new absorption band is formed and dominates the absorption spectrum, clearly demonstrates that the BNB-t8 has been hybridized with RGO, by combining the analysis of Raman and XRD data. Femtosecond Z-scan results present a highly enhanced saturable optical absorption of BNB-t8/RGO hybrid compared with that of RGO. By optimizing the hybridization ratio of BNB-t8 to RGO, the saturable absorption coefficient of BNB-t8/RGO hybrid reaches to -237 m/W, 38 times larger than that of RGO (-6.2 m/W). In the meantime, the third-order susceptibility χ(3) of BNB-t8/RGO hybrid is aslo enhanced by 8 times to be 5.18×10-13 esu. These enhancements of nonlinear optical properties of BNB-t8/RGO hybrid mainly arise from the charge transfer from RGO to BNB-t8. Femtosecond transient absorption measurements reveal that the charge separation takes place in 0.28 ps and the charge recombination in 2.0 ps, indicating a strong electron coupling and thus an enhanced electron delocalization in BNB-t8/RGO hybrid compared with those in RGO. We suggest that the noncovalent π-π interaction plays the dominant role for enhancing the electron delocalization of RGO after hybridizing with BNB-t8, while the hydrogen bonding interaction reinforce the coupling interaction between BNB-t8 and RGO moieties in the hybrid. The as-prepared BNB-t8/RGO hybrid with high saturable absorption coefficient with an ultrafast response presents a potential candidate as saturable absorber of mode-locked laser.

8.
Molecules ; 25(11)2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32486057

RESUMEN

Nanomaterials have been widely used in biomedical sciences; however, the mechanism of interaction between nanoparticles and biomolecules is still not fully understood. In the present study, we report the interaction mechanism between differently sized Ag nanoparticles and the improved light-oxygen-voltage (iLOV) protein. The steady-state and time-resolved fluorescence results demonstrated that the fluorescence intensity and lifetime of the iLOV protein decreased upon its adsorption onto Ag nanoparticles, and this decrease was dependent upon nanoparticle size. Further, we showed that the decrease of fluorescence intensity and lifetime arose from electron transfer between iLOV and Ag nanoparticles. Moreover, through point mutation and controlled experimentation, we demonstrated for the first time that electron transfer between iLOV and Ag nanoparticles is mediated by the tryptophan residue in the iLOV protein. These results are of great importance in revealing the function of iLOV protein as it applies to biomolecular sensors, the field of nano-photonics, and the interaction mechanism between the protein and nanoparticles.


Asunto(s)
Transporte de Electrón , Nanopartículas del Metal/química , Nanotecnología/métodos , Plata/química , Adsorción , Técnicas Electroquímicas , Electrones , Fluorescencia , Proteínas Luminiscentes/química , Oxígeno/química , Tamaño de la Partícula , Unión Proteica , Riboflavina/química , Espectrometría de Fluorescencia , Temperatura , Triptófano/química
9.
Small ; 14(48): e1803015, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30328265

RESUMEN

Layered serpentine Ni3 Ge2 O5 (OH)4 is compositionally active and structurally favorable for adsorption and diffusion of reactants in oxygen evolution reactions (OER). However, one of the major problems for these materials is limited active sites and low efficiency for OER. In this regard, a new catalyst consisting of layered serpentine Ni3 Ge2 O5 (OH)4 nanosheets is introduced via a controlled one-step synthetic process where the morphology, size, and layers are well tailored. The theoretical calculations indicate that decreased layers and increased exposure of (100) facets in serpentine Ni3 Ge2 O5 (OH)4 lead to much lower Gibbs free energy in adsorption of reactive intermediates. Experimentally, it is found that the reduction in number of layers with minimized particle size exhibits plenty of highly surface-active sites of (100) facets and demonstrates a much enhanced performance in OER than the corresponding multilayered nanosheets. Such a strategy of tailoring active sites of serpentine Ni3 Ge2 O5 (OH)4 nanosheets offers an effective method to design highly efficient electrocatalysts.

10.
Nanotechnology ; 29(23): 235101, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29570098

RESUMEN

We first illustrate the faster decrease of the photothermal (PT) effect with the delay time of laser treatment, in which the illumination of a 1064 nm laser effectively excites the localized surface plasmon (LSP) resonance of cell-up-taken gold nanoring (NRI) linked with a photosensitizer (PS), when compared with the photodynamic (PD) effect produced by the illumination of a 660 nm laser for effective PS excitation. The measurement results of the metal contents of Au NRI and PS based on inductively coupled plasma mass spectroscopy and the PS fluorescence intensity based on flow cytometry show that the linkage of NRI and PS is rapidly broken for releasing PS through the effect of glutathione in lysosome after cell uptake. Meanwhile, NRI escapes from a cell with a high rate such that the PT effect decays fast while the released PS can stay inside a cell longer for producing a prolonged PD effect. The effective delivery of PS through the linkage with Au NRI for cell uptake and the advantageous effect of LSP resonance at a PS absorption wavelength on the PD process are also demonstrated.


Asunto(s)
Exocitosis/efectos de los fármacos , Oro/química , Hipertermia Inducida , Nanopartículas del Metal/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Línea Celular Tumoral , Endocitosis/efectos de los fármacos , Fluorescencia , Humanos , Rayos Láser , Espectrofotometría Atómica , Resonancia por Plasmón de Superficie
11.
Molecules ; 23(12)2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30513670

RESUMEN

The methods of cell perforation and preheating are used for increasing cell uptake efficiencies of gold nanorings (NRIs), which have the localized surface plasmon resonance wavelength around 1064 nm, and photosensitizer, AlPcS, and hence enhancing the cell damage efficiency through the photothermal (PT) and photodynamic (PD) effects. The perforation and preheating effects are generated by illuminating a defocused 1064-nm femtosecond (fs) laser and a defocused 1064-nm continuous (cw) laser, respectively. Cell damage is produced by illuminating cell samples with a focused 1064-nm cw laser through the PT effect, a focused 1064-nm fs laser through both PT and PD effects, and a focused 660-nm cw laser through the PD effect. Under various conditions with and without cell wash before laser illumination, through either perforation or preheating process, cell uptake and hence cell damage efficiencies can be enhanced. Under our experimental conditions, perforation can be more effective at enhancing cell uptake and damage when compared with preheating.


Asunto(s)
Oro/química , Hipertermia Inducida , Nanopartículas del Metal/química , Neoplasias/patología , Fármacos Fotosensibilizantes/farmacología , Fototerapia , Línea Celular Tumoral , Fluorescencia , Humanos , Resonancia por Plasmón de Superficie
12.
Nanotechnology ; 28(27): 275101, 2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28557805

RESUMEN

The different death pathways of cancer cells under the conditions of the photothermal (PT), effect, photodynamic (PD) effect, and their combination are evaluated. By incubating cells with Au nanoring (NRI) either linked with the photosensitizer, AlPcS, or not, the illumination of a visible continuous laser for exciting the photosensitizer or an infrared femtosecond laser for exciting the localized surface plasmon resonance of Au NRI, leads to various PT and PD conditions for study. Three different staining dyes are used for identifying the cell areas of different damage conditions at different temporal points of observation. The cell death pathways and apoptotic evolution speeds under different cell treatment conditions are evaluated based on the calibration of the threshold laser fluences for causing early-apoptosis (EA) and necrosis (NE) or late-apoptosis (LA). It is found that with the PT effect only, strong cell NE is generated and the transition from EA into LA is faster than that caused by the PD effect when the EA stage is reached within 0.5 h after laser illumination. By combining the PT and PD effects, in the first few hours, the transition speed becomes lower, compared to the case of the PT effect only, when both Au NRIs internalized into cells and adsorbed on cell membrane exist. When the Au NRIs on cell membrane is removed, in the first few hours, the transition speed becomes higher, compared to the case of the PD effect only.

13.
Bioresour Technol ; 412: 131423, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39236906

RESUMEN

An innovative binary biol-based deep eutectic solvent (DES), specifically ethylamine hydrochloride-ethylene glycol (EaCl-EG), was developed for efficient pretreatment of eucalyptus biomass. This DES exhibited superior performance in achieving high delignification (85.0%) and xylan removal (80.0%), while preserving a significant amount of cellulose (94.5%) compared to choline chloride-based DES. Notably, the pretreated eucalyptus residues showed a remarkable glucose yield of over 92.5%, representing a substantial enhancement of up to 15 times compared to untreated eucalyptus. Furthermore, the pretreated liquor yielded high-purity lignin with a yield of 97.8%, characterized by well-preserved ß-O-4 structure and nanoscale dimensions. These lignin nanoparticles (LNPs) were subsequently self-assembled into lignin nanobottles (LNBs), adding further value to the pretreatment process. The proposed novel binary EaCl-EG DES presented great potential as an efficient pretreatment solvent for future biomass fractionation processes.


Asunto(s)
Biomasa , Fraccionamiento Químico , Disolventes Eutécticos Profundos , Eucalyptus , Lignina , Eucalyptus/química , Lignina/química , Disolventes Eutécticos Profundos/química , Fraccionamiento Químico/métodos , Hidrólisis , Celulasa/metabolismo , Celulasa/química , Glucosa/química , Solventes/química , Nanopartículas/química
14.
ACS Appl Mater Interfaces ; 16(25): 32282-32290, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38865690

RESUMEN

In the planar heterostructure of perovskite-based solar cells (PSCs), tin oxide (SnO2) is a material that is often used as the electron transport layer (ETL). SnO2 ETL exhibits favorable optical and electrical properties in the PSC structures. Nevertheless, the open circuit voltage (VOC) depletion occurs in PSCs due to the defects arising from the high oxygen vacancy on the SnO2 surface and the deeper conduction band (CB) energy level of SnO2. In this research, a cerium (Ce) dopant was introduced in SnO2 (Ce-SnO2) to suppress the VOC loss of the PSCs. The CB minimum of SnO2 was shifted closer to that of the perovskite after the Ce doping. Besides, the Ce doping effectively passivated the surface defects on SnO2 as well as improved the electron transport velocity by the Ce-SnO2. These results enabled the power conversion efficiency (PCE) to increase from 21.1% (SnO2) to 23.0% (Ce-SnO2) of the PSCs (0.09 cm2 active area) with around 100 mV of improved VOC and reduced hysteresis. Also, the Ce-SnO2 ETL-based large area (1.0 cm2) PSCs delivered the highest PCE of 22.9%. Furthermore, a VOC of 1.19 V with a PCE of 23.3% was demonstrated by Ce-SnO2 ETL-based PSCs (0.09 cm2 active area) that were treated with 2-phenethylamine hydroiodide on the perovskite top surface. Notably, the unencapsulated Ce-SnO2 ETL-based PSC was able to maintain above 90% of its initial PCE for around 2000 h which was stored under room temperature condition (23-25 °C) with a relative humidity of 40-50%.

15.
Int J Biol Macromol ; : 135293, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233160

RESUMEN

Castor stalk from hemp plants is an attractive lignocellulosic feedstock for biomass refining valorization due to its similar chemical composition to hardwoods. In this study, the castor stalk fibers were pretreated with efficient dual-functional ethanolamine to achieve delignification and swelling of the cellulosic fibers, followed by cellulase enzymatic digestion for biomass conversion. Experimental results showed that ethanolamine pretreatment at 160 °C for 1 h effectively removed 69.20 % of lignin and 43.18 % of hemicellulose. In addition to efficient delignification and removal of hemicellulose, the study also revealed that supramolecular structure of cellulose was another major factor affecting enzymatic hydrolysis performance. The lowered crystallinity (60-70 %) and swelled crystal sizes (2.95-3.04 nm) promoted enzymatic hydrolysis efficiency during the heterogeneous reaction process. Under optimal conditions (160 °C, 1 h; enzyme loading: 15 FPU/g substrate), promoted yields of 100 % glucose and over 90 % xylose were achieved, which were significantly higher than those obtained from untreated castor stalk. These findings highlighted the effectiveness of the dual-functional ethanolamine pretreatment strategy for efficient bioconversion of lignocellulosic feedstocks. Overall, this study provides valuable insights into the development of new strategies for the efficient utilization of biomass resources, which is essential for the sustainable development of our society.

16.
ACS Appl Mater Interfaces ; 16(27): 34510-34523, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38946393

RESUMEN

Photoluminescence (PL) metal nanoclusters (NCs) have attracted extensive attention due to their excellent physicochemical properties, good biocompatibility, and broad application prospects. However, developing water-soluble PL metal NCs with a high quantum yield (QY) and high stability for visual drug delivery remains a great challenge. Herein, we have synthesized ultrabright l-Arg-ATT-Au/Ag NCs (Au/Ag NCs) with a PL QY as high as 73% and excellent photostability by heteroatom doping and surface rigidization in aqueous solution. The as-prepared Au/Ag NCs can maintain a high QY of over 61% in a wide pH range and various ionic environments as well as a respectable resistance to photobleaching. The results from structure characterization and steady-state and time-resolved spectroscopic analysis reveal that Ag doping into Au NCs not only effectively modifies the electronic structure and photostability but also significantly regulates the interfacial dynamics of the excited states and enhances the PL QY of Au/Ag NCs. Studies in vitro indicate Au/Ag NCs have a high loading capacity and pH-triggered release ability of doxorubicin (DOX) that can be visualized from the quenching and recovery of PL intensity and lifetime. Imaging-guided experiments in cancer cells show that DOX of Au/Ag NCs-DOX agents can be efficiently delivered and released in the nucleus with preferential accumulation in the nucleolus, facilitating deep insight into the drug action sites and pharmacological mechanisms. Moreover, the evaluation of anticancer activity in vivo reveals an outstanding suppression rate of 90.2% for mice tumors. These findings demonstrate Au/Ag NCs to be a superior platform for bioimaging and visual drug delivery in biomedical applications.


Asunto(s)
Doxorrubicina , Oro , Nanopartículas del Metal , Plata , Agua , Oro/química , Plata/química , Plata/farmacología , Humanos , Animales , Doxorrubicina/química , Doxorrubicina/farmacología , Nanopartículas del Metal/química , Ratones , Agua/química , Sistemas de Liberación de Medicamentos , Células HeLa , Portadores de Fármacos/química , Solubilidad , Liberación de Fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Luminiscencia
17.
Small Methods ; 8(8): e2301319, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38178653

RESUMEN

The nitrogen doping (N-doping) treatment for niobium superconducting radio-frequency (SRF) cavities is one of the key enabling technologies that support the development of more efficient future large accelerators. However, the N-doping results have diverged due to a complex chemical profile under the nitrogen-doped surface. Particularly, under industrial-scale production conditions, it is difficult to understand the underlying mechanism thus hindering performance improvement. Herein, a combination of spatially resolved and surface-sensitive approaches is employed to establish the detailed near-surface phase composition of thermally processed niobium. The results show that intermediate phase segregations, particularly the nanometric carbon-rich phase, can impede the nitridation process and limit the interactions between nitrogen and the niobium sub-surface. In comparison, the removal of the carbon-rich layer at the Nb surface leads to enhanced nitrogen binding at the Nb surface. Combining the RF test results, it is shown that the complex uniformity and grain boundary penetrations of impurity elements have a direct correlation with the mid-field quench behavior in the N-doped Nb cavities. Therefore, proper control of the nanometric intermediate phase formation in discrete thermal steps is critical in improving the ultimate performance and production yield of the Nb cavities.

18.
ACS Appl Mater Interfaces ; 15(39): 45823-45833, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37738477

RESUMEN

Tin-based halide perovskite solar cells (Sn-PSCs) have attracted a progressive amount of attention as a potential alternative to lead-based PSCs (Pb-PSCs). Sn-perovskite films are fabricated by a solution process spin-coating technique. However, the efficiency of these devices varies significantly with the different batches of precursor solution due to the poor chemical stability of SnI2-DMSO and the oxidation of Sn2+ to Sn4+. This study investigated the origin of Sn2+ oxidation before film formation, and it was identified that the ionization of SnI2 in dimethyl sulfoxide (DMSO) causes the oxidation of free Sn2+ and I- ions. To address these issues, this study introduces the reductive additive 4-fluorophenylhydrazine hydrochloride (4F-PHCl) in the FASnI3 perovskite precursor solution. The hydrazine functional (-NH-NH2) group converted detrimental Sn4+ and I2 defects back to Sn2+ and I- in precursor solution while retaining the properties of the perovskite solution. Furthermore, the addition of 4F-PHCl in the precursor solution effectively slows the crystallization process, enhancing the crystallinity of FASnI3 perovskite films and guaranteeing the Sn2+/I- stoichiometric ratio, ultimately leading to a power conversion efficiency (PCE) of 10.86%. The hydrophobic fluorinated benzene ring in 4F-PHCl ensures moisture stability in perovskite films, allowing unencapsulated PSCs to retain over 92% of their initial PCE in an N2-filled glovebox for 130 days. Moreover, the 4F-PHCl-modified encapsulated PSCs showed superior operational stability for 420 h and maintained 95% of their initial PCE for 300 h under maximum power point tracking at 1 sun continuous illumination. This study's findings provide a promising pathway to create a controlled Sn-based perovskite precursor solution for highly reproducible and stable Pb-free Sn-PSCs.

19.
World J Clin Cases ; 11(14): 3261-3266, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37274041

RESUMEN

BACKGROUND: Primary seminal vesicle adenocarcinoma is a rare malignancy that is difficult to diagnose. CASE SUMMARY: A 54-year-old man with an 18-year history of a seminal vesicle cyst presented with worsening hematospermia that had persisted for one month. Dynamic contrast-enhanced computed tomography and pelvic magnetic resonance imaging indicated a mass with a cystic-solid component. Robot-assisted seminal vesicle tumor resection was performed, and primary seminal vesicle adenocarcinoma was confirmed pathologically. The patient received pelvic radiotherapy for six weeks, and to date, no evidence of recurrence has been found. CONCLUSION: Seminal vesicle cysts should be monitored long-term. Seminal vesicle adenocarcinoma presents with non-specific symptoms and can be diagnosed by immunohistochemistry.

20.
World J Clin Cases ; 11(32): 7911-7919, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38073679

RESUMEN

BACKGROUND: SMARCB1/INI-1 deficient sinonasal carcinoma (SDSC) is a rare subset of sinonasal undifferentiated carcinoma with a poor prognosis. Here, we present two case reports of SDSC patients. We also review the literature on this tumor. This is the first published report of SDSC treatment with immunotherapy. CASE SUMMARY: Here we present two patient cases of SDSC in which initial consultation and diagnosis were complicated but SDSC was ultimately diagnosed. One patient received a traditional treatment of surgery and adjuvant chemoradiotherapy, while the other patient received additional immunotherapy; the prognoses of these two patients differed. We review previous diagnostic literature reports and SDSC treatments and provide a unique perspective on this rare type of tumor. CONCLUSION: SDSC is a rare, diagnostically challenging carcinoma with a consistently poor prognosis, early distant metastases, and frequent recurrence. Timely diagnosis and intervention are critical for treatment, for which the standard of care is surgery followed by adjuvant chemoradiotherapy, though immunotherapy may be an effective new treatment for SDSC.

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