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1.
Nat Commun ; 15(1): 7778, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237586

RESUMO

Luminescent materials that simultaneously embody bright singlet and triplet excitons hold great potential in optoelectronics, signage, and information encryption. However, achieving high-performance white-light emission is severely hampered by their inherent unbalanced contribution of fluorescence and phosphorescence. Herein, we address this challenge by pressure treatment engineering via the hydrogen bonding cooperativity effect to realize the mixture of n-π*/π-π* transitions, where the triplet state emission was boosted from 7% to 40% in isophthalic acid (IPA). A superior white-light emission based on hybrid fluorescence and phosphorescence was harvested in pressure-treated IPA, and the photoluminescence quantum yield was increased to 75% from the initial 19% (blue-light emission). In-situ high-pressure IR spectra, X-ray diffraction, and neutron diffraction reveal continuous strengthening of the hydrogen bonds with the increase of pressure. Furthermore, this enhanced hydrogen bond is retained down to the ambient conditions after pressure treatment, awarding the targeted IPA efficient intersystem crossing for balanced singlet/triplet excitons population and resulting in efficient white-light emission. This work not only proposes a route for brightening triplet states in organic small molecules, but also regulates the ratio of singlet and triplet excitons to construct high-performance white-light emission.

2.
Research (Wash D C) ; 7: 0476, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286735

RESUMO

The interaction between organic and inorganic components in metal hybrid perovskites fundamentally determines the intrinsic optoelectronic performance. However, the underlying interaction sites have still remained elusive, especially for those non-hydrogen-bonded hybrid perovskites, thus largely impeding materials precise design with targeted properties. Herein, high pressure is utilized to elucidate the interaction mechanism between organic and inorganic components in the as-synthesized one-dimensional hybrid metal halide (DBU)PbBr3 (DBU = 1,8-diazabicyclo [5.4.0] undec-7-ene). The interaction sites are identified to be the N from DBU and the Br from inorganic framework by the indicative of enhanced Raman mode under high pressure. The change in interaction strength is indeed derived from the pressure modulation on both distance and spatial arrangement of the nearest Br and N, rather than traditional hydrogen-bonding effect. Furthermore, the enhanced interaction increased charge transfer, resulting in a cyan emission with photoluminescence quantum yields (PLQYs) of 86.6%. The enhanced cyan emission is particularly important for underwater communication due to the much less attenuation in water than at other wavelength emissions. This study provides deep insights into the underlying photophysical mechanism of non-hydrogen-bonded hybrid metal halides and is expected to impart innovative construction with superior performance.

3.
J Am Chem Soc ; 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39279160

RESUMO

Pressure-induced emission (PIE) is a compelling phenomenon that can activate luminescence within nonemissive materials. However, PIE in nonemissive organic materials has never been achieved. Herein, we present the first observation of PIE in an organic system, specifically within nonemissive azobenzene derivatives. The emission of 1,2-bis(4-(anthracen-9-yl)phenyl)diazene was activated at 0.52 GPa, primarily driven by local excitation promotion induced by molecular conformational changes. Complete photoisomerization suppression of the molecule was observed at 1.5 GPa, concurrently accelerating the emission enhancement to 3.53 GPa. Differing from the key role of isomerization inhibition in conventional perception, our findings demonstrate that the excited-state constituent is the decisive factor for emission activation, providing a potentially universal approach for high-efficiency azobenzene emission. Additionally, PIE was replicated in the analogue 1,2-bis(4-(9H-carbazol-9-yl)phenyl)diazene, confirming the general applicability of our findings. This work marks a significant breakthrough within the PIE paradigm and paves the novel high-pressure route for crystalline-state photoisomerization investigation.

4.
Angew Chem Int Ed Engl ; : e202412756, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107973

RESUMO

Simultaneous enhancement of free excitons (FEs) emission and self-trapped excitons (STEs) emission remains greatly challenging because of the radiative pathway competition. Here, a significant fluorescence improvement, associated with the radiative recombination of both FEs and STEs is firstly achieved in an unconventional ACI-type hybrid perovskite, (ACA)(MA)PbI4 (ACA=acetamidinium) crystals with {PbI6} octahedron units, through hydrostatic pressure processing. Note that (ACA)(MA)PbI4 exhibits a 91.5-fold emission enhancement and considerable piezochromism from green to red in a mild pressure interval of 1 atm to 2.5 GPa. The substantial distortion of both individual halide octahedron and the Pb-I-Pb angles between two halide octahedra under high pressure indeed determines the pressure-tuning localized excitons behavior. Upon higher pressure, photocurrent enhancement is also observed, which is attributed to the promoted electronic connectivity in (ACA)(MA)PbI4. The anisotropic compaction reduces the distance between neighboring organic molecules and {PbI6} octahedra, leading to the enhancement of hydrogen bonding interactions. This work not only offers a deep understanding of the structure-optical relationships of ACI-type perovskites, but also presents insights into breaking the limits of luminescent efficiency by pressure-suppressed nonradiative recombination.

5.
World J Gastroenterol ; 30(29): 3511-3533, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39156500

RESUMO

BACKGROUND: Calculus bovis (CB), used in traditional Chinese medicine, exhibits anti-tumor effects in various cancer models. It also constitutes an integral component of a compound formulation known as Pien Tze Huang, which is indicated for the treatment of liver cancer. However, its impact on the liver cancer tumor microenvironment, particularly on tumor-associated macrophages (TAMs), is not well understood. AIM: To elucidate the anti-liver cancer effect of CB by inhibiting M2-TAM polarization via Wnt/ß-catenin pathway modulation. METHODS: This study identified the active components of CB using UPLC-Q-TOF-MS, evaluated its anti-neoplastic effects in a nude mouse model, and elucidated the underlying mechanisms via network pharmacology, transcriptomics, and molecular docking. In vitro assays were used to investigate the effects of CB-containing serum on HepG2 cells and M2-TAMs, and Wnt pathway modulation was validated by real-time reverse transcriptase-polymerase chain reaction and Western blot analysis. RESULTS: This study identified 22 active components in CB, 11 of which were detected in the bloodstream. Preclinical investigations have demonstrated the ability of CB to effectively inhibit liver tumor growth. An integrated approach employing network pharmacology, transcriptomics, and molecular docking implicated the Wnt signaling pathway as a target of the antineoplastic activity of CB by suppressing M2-TAM polarization. In vitro and in vivo experiments further confirmed that CB significantly hinders M2-TAM polarization and suppresses Wnt/ß-catenin pathway activation. The inhibitory effect of CB on M2-TAMs was reversed when treated with the Wnt agonist SKL2001, confirming its pathway specificity. CONCLUSION: This study demonstrated that CB mediates inhibition of M2-TAM polarization through the Wnt/ß-catenin pathway, contributing to the suppression of liver cancer growth.


Assuntos
Neoplasias Hepáticas , Camundongos Nus , Simulação de Acoplamento Molecular , Microambiente Tumoral , Macrófagos Associados a Tumor , Via de Sinalização Wnt , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Humanos , Camundongos , Células Hep G2 , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/imunologia , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Masculino , Farmacologia em Rede , beta Catenina/metabolismo , Medicina Tradicional Chinesa/métodos
6.
Food Chem ; 460(Pt 3): 140818, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39137576

RESUMO

The effects of adsorption behavior and assembly mechanism of proteins and lipids at the interface on the formation of yuba films were investigated. The thickness of yuba films increased rapidly from nano to micro scale within minutes according to the scanning electron microscopy (SEM) images. The confocal laser scanning microscope (CLSM), SEM images, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the formation of protein aggregates (40-100 nm) was an essential requirement for the development of yuba. Meanwhile, a relatively loose spatial structure was formed by protein aggregates under the influence of water vapor. This structure served as the foundation for incorporating lipids. Interfacial adsorption kinetics indicated that increasing the concentration (from 3 to 9 mg/mL) of protein aggregates enhanced the rearrangement rate. This finding demonstrated that the variations of interfacial protein aggregate concentration were a crucial factor leading to the non-linear growth of film thickness.


Assuntos
Agregados Proteicos , Adsorção , Cinética , Embalagem de Alimentos/instrumentação , Propriedades de Superfície , Lipídeos/química , Proteínas/química
7.
Food Chem ; 459: 140314, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-39024881

RESUMO

The combined impact of initial state, pressure, and freezing on peroxidase denaturation during high-pressure freezing (HPF) processing of enzyme-containing foods remains unclear. This study investigated solid-liquid (initial low/high concentration) biphasic peroxidase using spectroscopic and computer simulation techniques to analyze structural changes affecting peroxidase (POD) activity under HPF. The results indicate that the primary factors determining POD activity during HPF treatment can be ranked as follows: concentration > physical state > pressure > freezing. Higher initial concentrations strengthen protein interactions, leading to a 1% increase in the molecular diameter and a 34% increase in molecular height of HL-POD, thereby increasing aggregation likelihood during crystallization and facilitating structural changes that activate enzymes by 6-17%. The amide I peak proves to be a reliable indicator for monitoring both POD activity and structural alterations. This study offers valuable insights for optimizing HPF technology in food processing.


Assuntos
Congelamento , Peroxidase , Pressão , Peroxidase/química , Peroxidase/metabolismo , Manipulação de Alimentos , Estabilidade Enzimática
8.
Nano Lett ; 24(32): 9898-9905, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39007697

RESUMO

The technology of combining multiple emission centers to exploit white-light-emitting (WLE) materials by taking advantage of porous metal-organic frameworks (MOFs) is mature, but preparing undoped WLE MOFs remains a challenge. Herein, a pressure-treated strategy is reported to achieve efficient white photoluminescence (PL) in undoped [Zn(Tdc)(py)]n nanocrystals (NCs) at ambient conditions, where the Commission International del'Eclairage coordinates and color temperature reach (0.31, 0.37) and 6560 K, respectively. The initial [Zn(Tdc)(py)]n NCs exhibit weak-blue PL consisting of localized excited (LE) and planarized intramolecular charge transfer (PLICT) states. After pressure treatment, the emission contributions of LE and PLICT states are balanced by increasing the planarization of subunits, thereby producing white PL. Meanwhile, the reduction of nonradiative decay triggered by the planarized structure results in 5-fold PL enhancement. Phosphor-converted light-emitting diodes based on pressure-treated samples show favorable white-light characteristics. The finding provides a new platform for the development of undoped WLE MOFs.

9.
Chem Sci ; 15(29): 11367-11373, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39055011

RESUMO

Exploration of pressure-resistant materials largely facilitates their operation under extreme conditions where a stable structure and properties are highly desirable. However, under extreme conditions, such as a high pressure over 30.0 GPa, fluorescence quenching generally occurs in most materials. Herein, pressure-induced emission enhancement (PIEE) by a factor of 4.2 is found in Ga2O3 nanocrystals (NCs), a fourth-generation ultrawide bandgap semiconductor. This is mainly attributed to pressure optimizing the intrinsic lattice defects of the Ga2O3 nanocrystals, which was further confirmed by first-principles calculations. Note that the bright blue emission could be stabilized even up to a high pressure of 30.6 GPa, which is of great significance in the essential components of white light. Notably, after releasing the pressure to ambient conditions, the emission of the Ga2O3 nanocrystals can completely recover, even after undergoing multiple repeated pressurizations. In addition to stable optical properties, synchrotron radiation shows that the Ga2O3 nanocrystals remain in the cubic structure described by space group Fd3m upon compression, demonstrating the structural stability of the Ga2O3 nanocrystals under high pressure. This study pays the way for the application of oxide nanomaterials in pressure anti-counterfeiting and pressure information memory devices.

10.
Int J Food Microbiol ; 422: 110814, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-38972103

RESUMO

Ohmic heating (OH), an emerging food processing technology employed in the food processing industry, raises potential food safety concerns due to the recovery of sublethally injured pathogens such as Staphylococcus aureus (S. aureus). In the present study, sensitivity to various stress conditions and the changes in cellular-related factors of OH-injured S. aureus during repair were investigated. The results indicated that liquid media differences (nutrient broth (NB), phosphate-buffered saline (PBS), milk, and cucumber juice) affected the recovery process of injured cells. Nutrient enrichment determines the bacterial repair rate, and the rates of repair for these media were milk > NB > cucumber juice > PBS. The sensitivity of injured cells to various stressors, including different acids, temperature, nisin, simulated gastric fluid, and bile salt, increased during the injury phase and subsequently diminished upon repair. Additionally, the intracellular ATP content, enzyme activities (Na+/K+-ATPase, Ca2+/Mg2+-ATPase, and T-ATPase) and ion concentrations (Mg2+, K+, and Ca2+) gradually increased during repair. After 5 h of repair, the intracellular substances content of cell's was significantly higher than that of the injured bacteria without repair, while some indicators (e.g., Na+/K+-ATPase, K+, and Ca2+) were not restored to the untreated level. The results of this study indicated that OH-injured S. aureus exhibited strengthened resistance post-recovery, potentially due to the restoration of cellular structures. These findings have implications for optimizing food storage conditions and advancing OH processes in the food industry.


Assuntos
Manipulação de Alimentos , Temperatura Alta , Staphylococcus aureus , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Estresse Fisiológico , Trifosfato de Adenosina/metabolismo
12.
Am J Case Rep ; 25: e944543, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39054659

RESUMO

BACKGROUND Odontogenic keratocyst (OKC) is a common odontogenic cyst, and it occurs more frequently in the mandible, with the posterior region of the dental arch, the angle, or the ramus being the most commonly affected sites. Odontogenic keratocyst occurring within the maxillary sinus is extremely rare, accounting for only about 1% of cases. CASE REPORT A 20-year-old female patient without any clinical symptoms underwent an oral examination, during which a dense dental shadow was identified within the maxillary sinus, surrounded by a low-density shadow. Physical examination revealed absence of the left maxillary third molar, with intact mucosa. The patient reported no history of tooth extraction. X-ray and cone-beam computed tomography revealed a high-density image within the left maxillary sinus, resembling a tooth and surrounded by a soft-tissue shadow, which exhibited a greater density in comparison to conventional odontogenic cysts. The initial diagnosis was odontogenic keratocyst in the maxillary sinus with an ectopic maxillary third molar. Surgical enucleation of the cyst and extraction of the impacted tooth were carried out utilizing the Caldwell-Luc approach. Histopathological analysis confirmed the presence of OKC. No significant recurrence was noted during the 6 months of follow-up. CONCLUSIONS Odontogenic keratocysts in the maxillary sinus with ectopic third molar are rare and may not have any symptoms in the early stage. Surgery can be performed using the Caroler-Luke approach to achieve ideal treatment results. In view of the high recurrence rate of OKC, close follow-up should be conducted after surgery.


Assuntos
Seio Maxilar , Dente Serotino , Cistos Odontogênicos , Humanos , Cistos Odontogênicos/cirurgia , Cistos Odontogênicos/diagnóstico por imagem , Feminino , Dente Serotino/cirurgia , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/patologia , Adulto Jovem , Tomografia Computadorizada de Feixe Cônico , Doenças dos Seios Paranasais/cirurgia , Doenças dos Seios Paranasais/diagnóstico por imagem , Extração Dentária
13.
Adv Sci (Weinh) ; : e2403813, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38981017

RESUMO

The strong ligand effect in B-doped Pd-based (PdB) catalysts renders them a promising anode for constructing formic acid fuel cells (FAFCs) exhibiting high power density and outstanding stability. However, the enhancement of the oxidation barrier is unavoidable in this alloy system owing to the electron transfer (ET) from B to Pd. In this study, a hydrogen doping strategy is employed to open charge freedom in PdB compounds and boost their formic acid oxidation reaction (FAOR) activity by suppressing the ET process. The resulting hydrogen-doped PdB (PdBH) exhibits an ultrahigh mass activity of up to 1.2A mg-1 Pd, which is 3.23 times that of the PdB catalyst and 9.55 times that of Pd black. Detailed experimental and theoretical studies show that the interstitial hydrogen leads to enhanced orbital hybridization and reduced electron density around Pd. This optimized ligand effect weakens the carbon monoxide adsorption and increases the direct pathway preference of PdBH, resulting in its outstanding catalytic activity for the FAOR. The development of this high-performance hydrogen-doped PdB catalyst is an important step toward the construction of advanced light element co-doped metal catalysts.

14.
Front Cell Dev Biol ; 12: 1430386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055653

RESUMO

The molecular mechanisms driving the onset and metastasis of prostate cancer remain poorly understood. Actin, under the control of actin-binding proteins (ABPs), plays a crucial role in shaping the cellular cytoskeleton, which in turn supports the morphological alterations in normal cells, as well as the invasive spread of tumor cells. Previous research indicates that ABPs of various types serve distinct functions, and any disruptions in their activities could predispose individuals to prostate cancer. These ABPs are intricately implicated in the initiation and advancement of prostate cancer through a complex array of intracellular processes, such as severing, linking, nucleating, inducing branching, assembling, facilitating actin filament elongation, terminating elongation, and promoting actin molecule aggregation. As such, this review synthesizes existing literature on several ABPs linked to prostate cancer, including cofilin, filamin A, and fascin, with the aim of shedding light on the molecular mechanisms through which ABPs influence prostate cancer development and identifying potential therapeutic targets. Ultimately, this comprehensive examination seeks to contribute to the understanding and management of prostate diseases.

15.
Angew Chem Int Ed Engl ; : e202409099, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38924238

RESUMO

Achieving enhanced or blue-shifted emission from piezochromic materials remains a major challenge. Covalent organic frameworks (COFs) are promising candidates for the development of piezochromic materials owing to their dynamic structures and adjustable optical properties, where the emission behaviors are not solely determined by the functional groups, but are also greatly influenced by the specific geometric arrangement. Nevertheless, this area remains relatively understudied. In this study, a successful synthesis of a series of bicarbazole-based COFs with varying topologies, dimensions, and linkages was conducted, followed by an investigation of their structural and emission properties under hydrostatic pressure generated by a diamond anvil cell. Consequently, these COFs exhibited distinct piezochromic behaviors, particularly a remarkable pressure-induced emission enhancement (PIEE) phenomenon with a 16-fold increase in fluorescence intensity from three-dimensional COFs, surpassing the performance of CPMs and most organic small molecules with PIEE behavior. On the contrary, three two-dimensional COFs with flexible structures exhibited rare blue-shifted emission, whereas the variants with rigid and conjugated structures showed common red-shifted and reduced emission. Mechanism research further revealed that these different piezochromic behaviors were primarily determined by interlayer distance and interaction. This study represents the first systematic exploration of the structures and emission properties of COFs through pressure-treated engineering and provides a new perspective on the design of piezochromic materials.

16.
Int J Food Microbiol ; 421: 110784, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38897047

RESUMO

Bacillus cereus spores pose a significant concern during food processing due to their high resistance to environmental stress. Ohmic heating (OH) is an emerging and alternative heating technology with potential for inactivating such spores. This study evaluated the inactivation effects and the biological property changes of Bacillus cereus spores during OH treatments. OH effectively inactivated spores in milk, orange juice, broth, rice soup, and buffer solution in less time than oil bath heating (OB). A decrease in NaCl content improved spore inactivation at the same temperature. Spores were more sensitive to acid at 80-85 °C with OH treatment. Furthermore, OH at 10 V/cm and 50 Hz could reduce the spore resistance and inhibit an increase in spore hydrophobicity and spore aggregation. Both heating methods resulted in significant dipicolinic acid (DPA) leakage and damage to the cortex and inner membranes of the spores. However, OH at 10 V/cm and 50 Hz had the lowest DPA leakage and inflicted the least damage to the inner membrane. The damage to the spore's inner membrane was considered the primary reason for inactivation by OB and OH treatments. Still, OH at 10 V/cm and 50 Hz might also block the germination or outgrowth of treated spores or cause damage to the spore core.


Assuntos
Bacillus cereus , Temperatura Alta , Esporos Bacterianos , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/efeitos da radiação , Bacillus cereus/crescimento & desenvolvimento , Microbiologia de Alimentos , Viabilidade Microbiana , Ácidos Picolínicos/farmacologia , Manipulação de Alimentos/métodos
17.
Int J Prosthodont ; 0(0): 1-22, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848506

RESUMO

OBJECTIVE: To investigate the effect of digital scanning combined with reverse engineering technology in the demonstration of full crown tooth preparation. METHODS: Thirty-one students were randomly divided into the two groups. The students in the control group carried out traditional demonstration by the use of eye-measurement methods. The students in the experimental group carried out improved demonstration by the use of digital intraoral scan with 3D measurement data. The students in both groups were provided with two resin teeth to conduct full crown tooth preparation on head model dental simulators. The teeth prepared before and after demonstration were scored by Chinese Stomatological Association Group Standards, with a total score of 100 points. Analysis of covariance was performed to comparatively analyze the scores related to the tooth surfaces, and convergence angle between two groups. RESULTS: Analysis of two prepared teeth (tooth #11 and #16) in two groups showed that there was a statistical significant difference in the mean score between the control group and experimental group (tooth #11, P = 0.0039) (tooth #16, P = 0.0120).The demonstration of the tooth #16 showed that there were statistical significant differences in the scores related to buccolingual surface (P = 0.0205) and proximal surface (P = 0.0023) between the control group and experimental group; There was a statistical significant difference in the score related to the convergence angle of buccolingual surface between the control group and experimental group (P = 0.0265). CONCLUSION: The digital methods can effectively improve the quality of tooth preparations and has a pedagogical advantage for posterior teeth, which present greater operational challenges.

18.
Anal Chem ; 96(23): 9399-9407, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804597

RESUMO

Fast and efficient sample pretreatment is the prerequisite for realizing surface-enhanced Raman spectroscopy (SERS) detection of trace targets in complex matrices, which is still a big issue for the practical application of SERS. Recently, we have proposed a highly performed liquid-liquid extraction (LLE)-back extraction (BE) for weak acids/bases extraction in drinking water and beverage samples. However, the performance efficiency decreased drastically on facing matrices like food and biological blood. Based on the total interaction energies among target, interferent, and extractant molecules, solid-phase extraction (SPE) with a higher selectivity was introduced in advance of LLE-BE, which enabled the sensitive (µg L-1 level) and rapid (within 10 min) SERS detection of both koumine (a weak base) and celastrol (a weak acid) in different food and biological samples. Further, the high SERS sensitivity was determined unmanned by Vis-CAD (a machine learning algorithm), instead of the highly demanded expert recognition. The generality of SPE-LLE-BE for various weak acids/bases (2 < pKa < 12), accompanied by the high efficiency, easy operation, and low cost, offers SERS as a powerful on-site and efficient inspection tool in food safety and forensics.


Assuntos
Extração em Fase Sólida , Análise Espectral Raman , Análise Espectral Raman/métodos , Extração Líquido-Líquido , Humanos , Triterpenos Pentacíclicos , Análise de Alimentos/métodos , Nanopartículas Metálicas/química
19.
Inorg Chem ; 63(24): 11431-11437, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38814822

RESUMO

Lead-free organic-inorganic hybrid perovskites are one class of promising optoelectronic materials that have attracted much attention due to their outstanding stability and environmentally friendly nature. However, the intrinsic band gap far from the Shockley-Queisser limit and the inferior electrical properties largely limit their applicability. Here, a considerable band-gap narrowing from 2.43 to 1.64 eV with the compression rate up to 32.5% is achieved via high-pressure engineering in the lead-free hybrid perovskite MA3Sb2I9. Meanwhile, the electric transport process changes from the initial interaction of both ions and electrons to only the contribution of electrons upon compression. The alteration in electrical characteristics is ascribed to the vibration limitation of organic ions and the enhanced orbital overlap, resulting from the reduction of the Sb-I bond length through pressure-induced phase transitions. This work not only systematically investigates the correlation between the structural and optoelectronic properties of MA3Sb2I9 but also provides a potential pathway for optimizing electrical properties in lead-free hybrid perovskites.

20.
Clin Case Rep ; 12(5): e8810, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38698875

RESUMO

Key Clinical Message: The phenomenon of vessel pedicle ossification is a noteworthy aspect of the repair and reconstruction of maxillofacial defects. Imaging findings typically reveal high-density shadows within the vascular pedicle pathway, which may be managed through conservative observation or surgical intervention as deemed appropriate. Abstract: Vessel pedicle ossification is a relatively uncommon complication associated with the reconstruction of oral and maxillofacial tissue defects using free tissue flap repair. In this paper, we report a case of pedicle ossification and conduct a comprehensive review of previous literature. A 39-year-old man presented with a limited ability to open his mouth 6 months after fibular flap reconstruction of the mandible. Plain film X-ray and computed tomography (CT) indicated pedicle ossification. Two years after the initial operation, the restriction in the patient's ability to open his mouth had not worsened, although there were more pronounced radiographic abnormalities.

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