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1.
Exp Cell Res ; 435(1): 113928, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190869

RESUMO

Abnormalities in the function of fibroblast-like synoviocytes (FLSs) are crucial factors leading to joint damage of rheumatoid arthritis. In recent years, the role of circular RNA (circRNA) in RA has gradually been revealed. However, the functional regulation of FLSs mediated by circRNA and its potential mechanisms remain unclear. In this study, we elucidated the expression profile of circRNA in FLSs, as well as the role and molecular mechanisms of circTldc1. Through sequencing and validation experiments on primary FLSs derived from collagen-induced arthritis (CIA) rats, we found that circTldc1 can promote FLSs proliferation and exacerbate CIA-induced joint damage. The data revealed that circTldc1's parent gene, Tldc1, is homologous to human Tldc1, and circTldc1 is located in the cytoplasm of FLSs, belonging to the exonic circRNA category. The results from bioinformatics analysis, molecular experiments on FLSs (manipulating circTldc1 expression in vitro), and animal experiments (local regulation of circTldc1 expression in vivo) collectively confirmed that circTldc1 promotes Tldc1 expression by targeting miR-485-5p. High expression of Tldc1 further enhances FLSs proliferation and inflammatory responses, thereby worsening joint damage in CIA rats. High expression of circTldc1 and its parent gene Tldc1 may serve as biomarkers for RA. Local regulation of circTldc1 and Tldc1 gene levels in the joint cavity may represent a potential strategy to improve joint damage and inflammation in RA.


Assuntos
Artrite Experimental , MicroRNAs , Sinoviócitos , Animais , Humanos , Ratos , Artrite Experimental/genética , Artrite Experimental/metabolismo , Proliferação de Células/genética , Células Cultivadas , Fibroblastos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Sinoviócitos/metabolismo
2.
Opt Lett ; 49(10): 2697-2700, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748139

RESUMO

High turbidity and its associated multiple scattering phenomena can often lead to an underestimation of the particle size for the laser scattering method. To investigate the light scattering characteristics and evaluate the effect of high-obscuration particle systems, a Monte Carlo model has been developed based on Mie's theory. A compact setup was utilized to perform a series of experiments on three certified reference materials (CRMs) at different concentrations. Both the scattered light energy distribution and the obscuration were measured simultaneously. The inversion results of the particle size indicate a continuous increase in deviation from the nominal value as the obscuration rises. According to the conventional single scattering model, the inversion errors fall within 5% for obscuration levels ranging from 0.15 to 0.2. However, for a higher obscuration, the error can reach approximately 15%. Thus, a correction method has been proposed by introducing an improved model matrix that includes the multiple scattering contribution for the data inversion, which exhibits a significant enhancement in the accuracy of particle size measurements under high obscuration conditions. For all three types of particles being studied, the error was successfully reduced to within 5.0%.

3.
Phys Rev Lett ; 132(7): 076503, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38427879

RESUMO

Transition metal dichalcogenide superlattices provide an exciting new platform for exploring and understanding a variety of phases of matter. The moiré continuum Hamiltonian, of two-dimensional jellium in a modulating potential, provides a fundamental model for such systems. Accurate computations with this model are essential for interpreting experimental observations and making predictions for future explorations. In this work, we combine two complementary quantum Monte Carlo (QMC) methods, phaseless auxiliary field quantum Monte Carlo and fixed-phase diffusion Monte Carlo, to study the ground state of this Hamiltonian. We observe a metal-insulator transition between a paramagnet and a 120° Néel ordered state as the moiré potential depth and the interaction strength are varied. We find significant differences from existing results by Hartree-Fock and exact diagonalization studies. In addition, we benchmark density-functional theory, and suggest an optimal hybrid functional which best approximates our QMC results.

4.
Langmuir ; 40(23): 11914-11926, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804978

RESUMO

Directly integrating ceramic vapor chambers into the insulating substrate of semiconductor power devices is an effective approach to solve the problem of heat dissipation. Microgrooves that could be machined directly on the shell plate without contact thermal resistance and mechanical dislocation offer exciting opportunities to achieve high-performance ceramic vapor chambers. In this study, a bioinspired hierarchical microgroove wick (BHMW) containing low ribs via one-step nanosecond pulsed laser processing was developed, as inspired by the Sarracenia trichome. The superwicking behavior of microgrooves with different structural parameters was investigated using capillary rise tests and droplet-spreading experiments. The BHMW exhibited excellent capillary performance and anisotropic hemiwicking performance. At a laser scanning spacing of 30 µm, the BHMW achieved a capillary wicking height of 114 mm within 20 s. The optimized BHMW demonstrated a capillary parameter (ΔPc·K) and an anisotropic hemiwicking ratio of 4.46 × 10-7 N and 11.93, respectively, which were 1182 and 946% higher than references, as achieved through nanosecond pulsed laser texturing under identical parameters. This work not only develops a high-performance hierarchical alumina microgroove wick structure but also outlines design guidelines for high-performance ceramic vapor chambers for thermal management in semiconductor power devices.

5.
Phys Chem Chem Phys ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935024

RESUMO

Non-transition metal doping, especially for Mg, has been gradually employed to optimize the electrochemical performance of Li-rich cathode material Li2MnO3. However, the effects of Mg doping on the electrochemical behavior of Li2MnO3 have not been studied extensively. In this work, we investigate the effect of Mg doping at both the 2b (in the Li/Mn mixed layer) and 4h (in the Li layer) Li sites on the electrochemical properties of Li2MnO3 through first-principles calculations and ab initio molecular dynamics simulations. The local lattice structure, electronic density of states, Bader charge, delithiation voltage, lattice oxygen stability and Li diffusion kinetics are examined. Electronic structure analysis shows that Mg can activate the electrochemical activity of surrounding Mn by charge transfer, making Mn participate in charge compensation at the initial delithiation stage. Mg doping can also cause an increase in the average oxygen vacancy formation energy and hence depress the oxygen release during the delithiation process. Molecular dynamics simulations show that the diffusion kinetics of Li ions in Mg2b-Li2MnO3 is enhanced with respect to the undoped one, whereas Mg doped at the 4h site cannot improve the diffusion kinetics of Li ions. Further studies found that Mg doped at the 2b site results in a decrease in the energy barrier for the intra-layer diffusion and an increase in the energy barrier for the inter-layer diffusion of the nearby Li vacancies.

6.
Environ Res ; : 119434, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945515

RESUMO

Nano-zero valent iron (nZVI) was anchored and dispersed on the surface of acid-modified blast furnace slag (mBFS) through the liquid phase reduction method. The synthesized nZVI@mBFS composite exhibited remarkable ability to degrade phenol when used in conjunction with persulfate (PDS), 97.8% phenol could be eliminated in 30 min. All the anions like SO42-, HCO3-, H2PO4-, and CO32- were detrimental to the phenol degradation in nZVI@mBFS system. Moreover, electron paramagnetic resonance (EPR) analysis and radical scavenging tests confirmed that , and were the principal reactive oxygen species (ROSs) generated during the reaction process. The potential degradation pathways were also deduced based on the results obtained from gas chromatograph-mass spectrometer (GC-MS) analysis. Collectively, this study holds substantial significance in regards to recycling industrial solid wastes, devising efficient persulfate-activated materials, and treating wastewater.

7.
Int Wound J ; 21(2): e14733, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38339798

RESUMO

Keloids, pathological scars resulting from skin trauma, have traditionally posed significant clinical management challenges due to their persistence and high recurrence rates. Our research elucidates the pivotal roles of lipids and their derivatives in keloid development, driven by underlying mechanisms of abnormal cell proliferation, apoptosis, and extracellular matrix deposition. Key findings suggest that abnormalities in arachidonic acid (AA) synthesis and non-essential fatty acid synthesis are integral to keloid formation. Further, a complex interplay exists between lipid derivatives, notably butyric acid (BA), prostaglandin E2 (PGE2), prostaglandin D2 (PGD2), and the regulation of hyperfibrosis. Additionally, combinations of docosahexaenoic acid (DHA) with BA and 15-deoxy-Δ12,14-Prostaglandin J2 have exhibited pronounced cytotoxic effects. Among sphingolipids, ceramide (Cer) displayed limited pro-apoptotic effects in keloid fibroblasts (KFBs), whereas sphingosine 1-phosphate (S1P) was found to promote keloid hyperfibrosis, with its analogue, FTY720, demonstrating contrasting benefits. Both Vitamin D and hexadecylphosphorylcholine (HePC) showed potential antifibrotic and antiproliferative properties, suggesting their utility in keloid management. While keloids remain a prevalent concern in clinical practice, this study underscores the promising potential of targeting specific lipid molecules for the advancement of keloid therapeutic strategies.


Assuntos
Queloide , Humanos , Queloide/tratamento farmacológico , Queloide/patologia , Matriz Extracelular , Fibrose , Apoptose , Lipídeos/farmacologia , Lipídeos/uso terapêutico , Fibroblastos
8.
Small ; 19(52): e2304264, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37661567

RESUMO

Transition metal oxides, highly motivated anodes for lithium-ion batteries due to high theoretical capacity, typically afflict by inferior conductivity and significant volume variation. Architecting heterogeneous structures with distinctive interfacial features can effectively regulate the electronic structure to favor electrochemical properties. Herein, an engineered carbon-coated nanosized Fe3 O4 /Cr2 O3 heterostructure with multiple interfaces is synthesized by a facile sol-gel method and subsequent heat treatment. Such ingenious components and structural design deliver rapid Li+ migration and facilitate charge transfer at the heterogeneous interface. Simultaneously, the strong coupling synergistic interactions between Fe3 O4 , Cr2 O3 , and carbon layers establish multiple interface structures and built-in electric fields, which accelerate ion/electron transport and effectively eliminate volume expansion. As a result, the multi-interface heterostructure, as a lithium-ion battery anode, exhibits superior cycling stability maintaining a reversible capacity of 651.2 mAh g-1 for 600 cycles at 2 C. The density functionaltheory calculations not only unravel the electronic structure of the modulation but also illustrate favorable lithium-ion adsorption kinetics. This multi-interface heterostructure strategy offers a pathway for the development of advanced alkali metal-ion batteries.

9.
Chemistry ; 29(66): e202302093, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37668304

RESUMO

The cellular compartment plays an essential role in organizing the complex and diverse biochemical reactions within the cell. By mimicking the function of such cellular compartments, the challenge of constructing artificial compartments has been taken up to develop new biochemical tools for efficient material production and diagnostics. The important features required for the artificial compartment are that it isolates the interior from the external environment and is further functionalized to control the transport of target chemicals to regulate the interior concentration of both substrate and reaction products. In this study, an artificial compartment with size-selective molecular transport function was constructed by using a DNA origami-guided liposome prepared by modifying the method reported by Perrault et al. This completely isolates the liposome interior, including the DNA origami skeleton, from the external environment and allows the assembly of a defined number of molecules of interest inside and/or outside the compartment. By incorporating a bacterial membrane protein, OmpF, into the liposome, the resulting artificial compartment was shown to transport only the molecule of interest with a molecular weight below 600 Da from the external environment into the interior of the compartment.


Assuntos
DNA , Lipossomos , Lipossomos/química , Transporte Biológico , DNA/química
10.
Phys Chem Chem Phys ; 25(3): 2282-2293, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36597902

RESUMO

The poor cycling performance of Li-rich cathode Li2MnO3, a promising cathode for next-generation Li-ion batteries, limits its commercial applications. Transition metal (TM) doping is widely applied to optimize the electrochemical performance of Li2MnO3, where the d valence electrons of the TM play a crucial role. Nevertheless, the rule of the doping effect of TM with various numbers of d electrons has not been well summarized. In this work, 4d-TMs (Zr, Nb, Mo, Ru and Rh) are selected as dilute doping elements for Li2MnO3 to evaluate their effect on the performance of Li2MnO3 through first-principles calculations. The calculations indicate that as the number of 4d electrons increases, the doped TM transforms from an electrochemically inert state (Zr and Nb) to an electrochemically active state (Mo, Ru and Rh) in Li2MnO3. Meanwhile, the orbital hybridization between the 4d electrons of the TM and the 2p electrons of O becomes stronger from Zr to Rh, which promotes the co-oxidation of the TM and O for charge compensation and alleviates the excessive oxidation of O, thus enhancing the stability of O. Moreover, the oxidation of the doped TM and lattice Mn during charging can trigger a decrease in the initial average delithiation potential. Although the 4d-TMs exhibit slight promoting or inhibiting effects on Li diffusion, no obvious rule related to the number of d electrons has been found. Our work highlights the rule of the doping effect of TMs with different 4d electrons on the electrochemical performance of Li2MnO3 and would facilitate a better design of Li2MnO3 cathode materials.

11.
J Chem Phys ; 158(23)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37338033

RESUMO

Molecular magnets have received significant attention because of their potential applications in quantum information and quantum computing. A delicate balance of electron correlation, spin-orbit coupling (SOC), ligand field splitting, and other effects produces a persistent magnetic moment within each molecular magnet unit. The discovery and design of molecular magnets with improved functionalities would be greatly aided by accurate computations. However, the competition among the different effects poses a challenge for theoretical treatments. Electron correlation plays a central role since d- or f-element ions, which provide the magnetic states in molecular magnets, often require explicit many-body treatments. SOC, which expands the dimensionality of the Hilbert space, can also lead to non-perturbative effects in the presence of strong interaction. Furthermore, molecular magnets are large, with tens of atoms in even the smallest systems. We show how an ab initio treatment of molecular magnets can be achieved with auxiliary-field quantum Monte Carlo, in which electron correlation, SOC, and material specificity are included accurately and on an equal footing. The approach is demonstrated by an application to compute the zero-field splitting of a locally linear Co2+ complex.

12.
J Chem Phys ; 158(14): 140901, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37061483

RESUMO

Approximate solutions to the ab initio electronic structure problem have been a focus of theoretical and computational chemistry research for much of the past century, with the goal of predicting relevant energy differences to within "chemical accuracy" (1 kcal/mol). For small organic molecules, or in general, for weakly correlated main group chemistry, a hierarchy of single-reference wave function methods has been rigorously established, spanning perturbation theory and the coupled cluster (CC) formalism. For these systems, CC with singles, doubles, and perturbative triples is known to achieve chemical accuracy, albeit at O(N7) computational cost. In addition, a hierarchy of density functional approximations of increasing formal sophistication, known as Jacob's ladder, has been shown to systematically reduce average errors over large datasets representing weakly correlated chemistry. However, the accuracy of such computational models is less clear in the increasingly important frontiers of chemical space including transition metals and f-block compounds, in which strong correlation can play an important role in reactivity. A stochastic method, phaseless auxiliary-field quantum Monte Carlo (ph-AFQMC), has been shown to be capable of producing chemically accurate predictions even for challenging molecular systems beyond the main group, with relatively low O(N3 - N4) cost and near-perfect parallel efficiency. Herein, we present our perspectives on the past, present, and future of the ph-AFQMC method. We focus on its potential in transition metal quantum chemistry to be a highly accurate, systematically improvable method that can reliably probe strongly correlated systems in biology and chemical catalysis and provide reference thermochemical values (for future development of density functionals or interatomic potentials) when experiments are either noisy or absent. Finally, we discuss the present limitations of the method and where we expect near-term development to be most fruitful.

13.
BMC Urol ; 23(1): 206, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082379

RESUMO

BACKGROUND: In this study, we explored the diagnostic performances of multiparametric magnetic resonance imaging (mpMRI), 68 Ga-PSMA-11 PET/CT and combination of 68 Ga-PSMA-11 PET/CT and mpMRI (mpMRI + PET/CT) for extracapsular extension (ECE). Based on the analyses above, we tested the feasibility of using mpMRI + PET/CT results to predict T staging in prostate cancer patients. METHODS: By enrolling 75 patients of prostate cancer with mpMRI and 68 Ga-PSMA-11 PET/CT before radical prostatectomy, we analyzed the detection performances of ECE in mpMRI, 68 Ga-PSMA-11 PET/CT and mpMRI + PET/CT on their lesion images matched with their pathological sample images layer by layer through receiver operating characteristics (ROC) analysis. By inputting the lesion data into Prostate Imaging Reporting and Data System (PI-RADS), we divided the lesions into different PI-RADS scores. The improvement of detecting ECE was analyzed by net reclassification improvement (NRI). The predictors for T staging were evaluated by using univariate and multivariable analysis. The Kappa test was used to evaluate the prediction ability. RESULTS: One hundred three regions of lesion were identified from 75 patients. 50 of 103 regions were positive for ECE. The ECE diagnosis AUC of mpMRI + PET/CT is higher than that of mpMRI alone (ΔAUC = 0.101; 95% CI, 0.0148 to 0.1860; p < 0.05, respectively). Compared to mpMRI, mpMRI + PET/CT has a significant improvement in detecting ECE in PI-RADS 4-5 (NRI 36.1%, p < 0.01). The diagnosis power of mpMRI + PET/CT was an independent predictor for T staging (p < 0.001) in logistic regression analysis. In patients with PI-RADS 4-5 lesions, 40 of 46 (87.0%) patients have correct T staging prediction from mpMRI + PET/CT (κ 0.70, p < 0.01). CONCLUSION: The prediction of T staging in PI-RADS 4-5 prostate cancer patients by mpMRI + PET/CT had a quite good performance.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radioisótopos de Gálio , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos
14.
Proc Natl Acad Sci U S A ; 117(44): 27231-27237, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33087572

RESUMO

We present a comprehensive theoretical study of the phase diagram of a system of many Bose particles interacting with a two-body central potential of the so-called Lennard-Jones form. First-principles path-integral computations are carried out, providing essentially exact numerical results on the thermodynamic properties. The theoretical model used here provides a realistic and remarkably general framework for describing simple Bose systems ranging from crystals to normal fluids to superfluids and gases. The interplay between particle interactions on the one hand and quantum indistinguishability and delocalization on the other hand is characterized by a single quantumness parameter, which can be tuned to engineer and explore different regimes. Taking advantage of the rare combination of the versatility of the many-body Hamiltonian and the possibility for exact computations, we systematically investigate the phases of the systems as a function of pressure (P) and temperature (T), as well as the quantumness parameter. We show how the topology of the phase diagram evolves from the known case of 4He, as the system is made more (and less) quantum, and compare our predictions with available results from mean-field theory. Possible realization and observation of the phases and physical regimes predicted here are discussed in various experimental systems, including hypothetical muonic matter.

15.
Altern Ther Health Med ; 29(8): 793-797, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37708554

RESUMO

Objective: To analyze the application effect of damage control surgery (DCS) combined with seamless integrated rescue mode in emergency treatment of severe thoracic and abdominal trauma. Methods: The clinical data of 90 patients with severe thoracic and abdominal trauma admitted to the emergency room of our hospital from September 2020 to September 2021 were selected for the retrospective analysis. According to the different treatment methods, they were divided into the experimental group (EG) and the control group (CG), with 45 cases in each group. The CG was treated with seamless integrated rescue mode, and the EG received the DCS combined with seamless integrated rescue mode. The mortality, complication rate, mixed venous oxygen saturation (SvO2), cardiac index (CI), central venous pressure (CVP), prothrombin time (PT), active partial thromboplastin time (APTT), the content of arterial blood lactate (ABL), C-reactive protein (CRP), interleukin-6 (IL-6) and interleukin-10 (IL-10) were compared between the two groups. Results: Compared with the CG, after intervention, the levels of SvO2, CI, CVP, APTT and IL-10 in the EG were signally higher (all P < .05), while the levels of PT, ABL, CRP and IL-6 in the EG were memorably lower (all P < .05), and the mortality and complication rate in the EG were notably lower (all P < .05). Conclusion: The application of DCS combined with seamless integrated rescue mode in emergency treatment of patients with severe thoracic and abdominal trauma can effectively reduce the mortality of patients, improve their coagulation dysfunction, decrease the level of inflammatory factors and reduce the occurrence of complications, with a positive significance for improving disease prognosis.


Assuntos
Interleucina-10 , Interleucina-6 , Humanos , Estudos Retrospectivos , Prognóstico , Proteína C-Reativa , Tratamento de Emergência
16.
J Wound Ostomy Continence Nurs ; 50(5): 420-426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37713355

RESUMO

BACKGROUND: Mucocutaneous separation (MCS) is one of the early stomal complications of ileal conduit diversion after radical cystectomy. It can result in abdominal infection and sepsis, prolonging patient recovery. Negative pressure wound therapy (NPWT) has been widely used for abdominal wounds after orthopedic and burn surgery. This case series describes its use in complicated MCS and ostomy retraction after ileal conduit diversion. CASES: We describe a case series of 3 patients with moderate to severe MCS with and without infection after robot-assisted radical cystectomy with ileal conduit diversion. Our patients were treated with NPWT to avoid infection and create a satisfactory environment for healing MCS. After 2 to 4 weeks of NPWT, all 3 patients had normal micturition function with no additional peristomal wounds or complications. CONCLUSION: Negative pressure wound therapy may be used in the management of complicated MCS after ileal conduit diversion.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Neoplasias da Bexiga Urinária , Derivação Urinária , Humanos , Neoplasias da Bexiga Urinária/etiologia , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/efeitos adversos , Cistectomia/efeitos adversos , Bexiga Urinária
17.
Anal Chem ; 94(39): 13463-13472, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36131359

RESUMO

Developing an easily-prepared, sensitive, and accurate point-of-need immunochromatographic assay (ICA) is significant in food safety screening, clinical diagnosis, and environmental monitoring. However, the current single-modal ICAs are limited in certain instinct drawbacks that restrict analytical performances. Herein, we introduce an ultrasensitive dual-modal colorimetric/reversed ratiometric fluorescence ICA based on facilely prepared immunoprobes with a high loading capacity of red quantum dots and AuNPs. By smartly integrating these red-colored/fluorescent signal probes with an immobilized green quantum dot antigen on the test lines, discrete "turn-on" visual inspection and reversed ratiometric quantification via a portable smartphone-based analyzer were accomplished. As an application, this method was employed to detect 11 phosphodiesterase-5 inhibitors in health foods with ultralow detection limits (0.0028-0.045 ng/mL), high repeatability (coefficient of variations of 0.3-1.91%), and reasonable accuracy (recoveries of 86.6-107%). The proposed method was further validated by the authorized liquid chromatography with tandem mass spectrometry method in actual sample detection. This new assay format can be extended to ultrasensitive flexible detection of other food contaminants, environmental pollutants, or tumor biomarkers within minutes, and it just requires simply prepared signal reporters, easy-to-operate procedures, and a low-cost miniaturized analyzer.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Pontos Quânticos , Biomarcadores Tumorais , Colorimetria , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Corantes Fluorescentes , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Pontos Quânticos/química
18.
Small ; 18(6): e2106273, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854564

RESUMO

Heterogeneous atoms substitution is an efficient method for promoting Li+ storage of transition metal oxides. Herein, a series of Fe-substituted MnO solid solutions with different Fe contents are synthesized by a feasible solid-phase method. The synergistic effects between heterogeneous atoms and rich vacancies are synchronously obtained, which hold distinctive electronic structures and substantial active sites. When optimized Mn0.55 Fe0.45 O solid solution as anodes for lithium-ion batteries, pre-prepared electrodes exhibit reversible lithium storage of 1286.9 mAh g-1 at 1 A g -1 after 400 cycles and even 628.1 mAh g-1 at 2 A g-1 after 1000 cycles. The LiCoO2 //Mn0.55 Fe0.45 O full cells are assembled, achieving the reversible capacity of 130.2 and 111.3 mAh g-1 after 150 cycles at 0.1 and 0.2 A g-1 , respectively. Density functional theory calculations also authenticate that the electrochemical activity can be markedly boosted by the heterogeneous atoms substituted Mn1 -x Fex O solid solution.

19.
Phys Rev Lett ; 128(20): 203201, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35657857

RESUMO

Leveraging cutting-edge numerical methodologies, we study the ground state of the two-dimensional spin-polarized Fermi gas in an optical lattice. We focus on systems at high density and small spin polarization, corresponding to the parameter regime believed to be most favorable to the formation of the elusive Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superfluid phase. Our systematic study of large lattice sizes, hosting nearly 500 atoms, provides strong evidence of the stability of the FFLO state in this regime, as well as a high-accuracy characterization of its properties. Our results for the density correlation function reveal the existence of density order in the system, suggesting the possibility of an intricate coexistence of long-range orders in the ground state. The ground-state properties are seen to differ significantly from the standard mean-field description, providing a compelling avenue for future theoretical and experimental explorations of the interplay between spin imbalance, strong interactions, and superfluidity in an exotic phase of matter.

20.
Phys Rev Lett ; 129(7): 076403, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36018705

RESUMO

We perform large-scale, numerically exact calculations on the two-dimensional interacting Fermi gas with a contact attraction. Reaching much larger lattice sizes and lower temperatures than previously possible, we determine systematically the finite-temperature phase diagram of the Berezinskii-Kosterlitz-Thouless (BKT) transitions for interaction strengths ranging from BCS to crossover to BEC regimes. The evolutions of the pairing wave functions and the fermion and Cooper pair momentum distributions with temperature are accurately characterized. In the crossover regime, we find that the contact has a nonmonotonic temperature dependence, first increasing as temperature is lowered, and then showing a slight decline below the BKT transition temperature to approach the ground-state value from above.

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