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1.
Clin Cosmet Investig Dermatol ; 17: 1183-1191, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800356

RESUMO

Background: Hematoporphyrin monomethyl ether (HMME) is a promising photosensitizer for photodynamic therapy (PDT) and has found wide application in the treatment of port-wine stains (PWS). Objective: This study aims to observe and analyze the clinical efficacy and safety of HMME-PDT in the treatment of PWS patients. It also aims to evaluate the usefulness of color Doppler flow imaging (CDFI), an ultrasound technique for detecting blood flow in skin lesions, in assessing clinical efficacy. Methods: Thirty-three patients with PWS underwent HMME-PDT at our dermatology outpatient clinic between January 2019 and March 2020. Data on patient demographics, lesion location, lesion type (pink, purple, nodular thickening), treatment frequency, and pre- and post-treatment images were collected and retrospectively analyzed. CDFI was performed on three patients. Results: All patients received intravenous HMME and underwent irradiation with 532 nm green LED light. Of these, 5 patients received 1 session of HMME-PDT, 14 received 2 sessions, 9 received 3 sessions and the remaining 5 patients received more than 3 sessions. Of the 33 patients, 9 were cured (27.27%), 10 showed improvement (30.30%), 11 experienced a reduction in symptoms (33.33%), and 3 showed no significant improvement (9.09%). Most patients reported local pain and oedema, and no systemic adverse effects were observed. Clinical efficacy correlated with lesion type and total number of treatment sessions. CDFI appears to be an excellent technique for assessing clinical efficacy. Conclusion: HMME-PDT is a safe and effective method for the treatment of PWS. CDFI examination appears to be a promising assessment tool. However, further validation with larger sample sizes is warranted.

2.
Nat Commun ; 15(1): 914, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291033

RESUMO

Perovskite materials and their applications in optoelectronics have attracted intensive attentions in recent years. However, in-depth understanding about their anisotropic behavior in ultrafast carrier dynamics is still lacking. Here we explore the ultrafast dynamical evolution of photo-excited carriers and photoluminescence based on differently-oriented MAPbBr3 wafers. The distinct in-plane polarization of carrier relaxation dynamics of the (100), (110) and (111) wafers and their out-of-plane anisotropy in a picosecond time scale were found by femtosecond time- and polarization-resolved transient transmission measurements, indicating the relaxation process dominated by optical/acoustic phonon interaction is related to photoinduced transient structure rearrangements. Femtosecond laser two-photon fabricated patterns exhibit three orders of magnitude enhancement of emission due to the formation of tentacle-like microstructures. Such a ultrafast dynamic study carried on differently-oriented crystal wafers is believed to provide a deep insight about the photophysical process of perovskites and to be helpful for developing polarization-sensitive and ultrafast-response optoelectronic devices.

3.
Nanomicro Lett ; 15(1): 189, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37515627

RESUMO

Hydrogen production from electrolytic water is an important sustainable technology to realize renewable energy conversion and carbon neutrality. However, it is limited by the high overpotential of oxygen evolution reaction (OER) at the anode. To reduce the operating voltage of electrolyzer, herein thermodynamically favorable glycerol oxidation reaction (GOR) is proposed to replace the OER. Moreover, vertical NiO flakes and NiMoNH nanopillars are developed to boost the reaction kinetics of anodic GOR and cathodic hydrogen evolution, respectively. Meanwhile, excluding the explosion risk of mixed H2/O2, a cheap organic membrane is used to replace the expensive anion exchange membrane in the electrolyzer. Impressively, the electrolyzer delivers a remarkable reduction of operation voltage by 280 mV, and exhibits good long-term stability. This work provides a new paradigm of hydrogen production with low cost and good feasibility.

4.
Inorg Chem ; 61(46): 18380-18389, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36346941

RESUMO

Studying ultrafast dynamics provides us with a way to modify materials from the timescale of particle interaction, and the related research on antiferromagnetic semiconductors is still inadequate. Based on the electron density reconstruction, we achieve the visualization of magnetic interactions of bulk antiferromagnetic MnPS3 in the ground state, reveal the role of two atomic site occupations of S atoms in different magnetic phase transitions, and provide the theoretical and experimental support for modifying magnetic properties by selectively replacing the S atom. The ultrafast carrier dynamics can provide information from the excited state to the ground state. Based on time-resolved transmittance measurements, ultrafast carrier dynamics of MnPS3 are reported. The phonon-assisted gap transition driven by the electronic structure is characterized. The coupling relationship among electrons, spin, and phonons is established. Furthermore, the spin orientations within different phases are confirmed.

5.
J Phys Chem Lett ; 13(46): 10778-10785, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36374552

RESUMO

The one-dimensional van der Waals (1D vdW) material fibrous red phosphorus (FRP) nanotubes are a promising direct-bandgap semiconductor with high carrier mobility and anisotropic optical responses because of low deformation potential and dangling-bond-free anisotropic interface. Employing first-principles calculations, we captured the potential of 1D FRP nanotubes. The thermal stability of 1D FRP nanotubes was confirmed by phonon calculation. Meanwhile, Raman spectroscopy indicated the strong vibration mode (366 cm-1) is along the phosphorus nanotube. Interestingly, spatial anisotropy bandgaps were found along with various stacking orientations. The charge transport calculations showed that the 1D FRP nanotube has a high hole mobility (499.2 cm2 V-1 s-1), considering the weak acoustic phonon scattering. More importantly, we found that the hole mobility changes dramatically (down to 7.1 cm2 V-1 s-1) under the strain, and the strain-dependent charge transport property of 1D FRP nanotubes could be considered to have many potential applications for electronics, optoelectronics, and switching devices.

6.
Beilstein J Nanotechnol ; 13: 788-795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105693

RESUMO

The KP15 nanowires with one-dimensional properties has a defect-free surface, high anisotropy, and carrier mobility which is desirable for the development of novel nanodevices. However, the preparation of nanoscale KP15 is still inefficient. In this work, the Hansen solubility parameters of KP15 were first obtained. Based on the Hansen's empirical theory, the concentration of liquid-exfoliated KP15 nanowires was improved to 0.0458 mg·mL-1 by a solution containing 50% water and 50% acetone. Approximately 79% of the KP15 nanowires had a thickness value below 50 nm and 60.9% of them had a width value below 100 nm. The thinnest KP15 nanowires reached 5.1 nm and had smooth boundaries. Meanwhile, strong temperature-dependent Raman response in exfoliated KP15 nanowires has been observed, which indicates a strong phonon-phonon coupling in those nanowires. This is helpful for non-invasive temperature measurements of KP15 nanodevices.

7.
Nat Commun ; 13(1): 2916, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614111

RESUMO

To achieve zero-carbon economy, advanced anode catalysts are desirable for hydrogen production and biomass upgrading powered by renewable energy. Ni-based non-precious electrocatalysts are considered as potential candidates because of intrinsic redox attributes, but in-depth understanding and rational design of Ni site coordination still remain challenging. Here, we perform anodic electrochemical oxidation of Ni-metalloids (NiPx, NiSx, and NiSex) to in-situ construct different oxyanion-coordinated amorphous nickel oxyhydroxides (NiOOH-TOx), among which NiOOH-POx shows optimal local coordination environment and boosts electrocatalytic activity of Ni sites towards selective oxidation of methanol to formate. Experiments and theoretical results demonstrate that NiOOH-POx possesses improved adsorption of OH* and methanol, and favors the formation of CH3O* intermediates. The coordinated phosphate oxyanions effectively tailor the d band center of Ni sites and increases Ni-O covalency, promoting the catalytic activity. This study provides additional insights into modulation of active-center coordination environment via oxyanions for organic molecules transformation.

8.
Phys Rev Lett ; 128(1): 015701, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061460

RESUMO

Metals usually have three crystal structures: face-centered cubic (fcc), body-centered cubic (bcc), and hexagonal-close packed (hcp) structures. Typically, metals exhibit only one of these structures at room temperature. Mechanical processing can cause phase transition in metals, however, metals that exhibit all the three crystal structures have rarely been approached, even when hydrostatic pressure or shock conditions are applied. Here, through in situ observation of the atomic-scale bending and tensile process of ∼5 nm-sized Ag nanowires (NWs), we show that bending is an effective method to facilitate fcc-structured Ag to access all the above-mentioned structures. The process of transitioning the fcc structure into a bcc structure, then into an hcp structure, and finally into a re-oriented fcc structure under bending has been witnessed in its entirety. This re-oriented fcc structure is twin-related to the matrix, which leads to twin nucleation without the need for partial dislocation activities. The results of this study advance our understanding of the deformation mechanism of small-sized fcc metals.

9.
Infect Genet Evol ; 96: 105137, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34781038

RESUMO

BACKGROUND: Syphilis is a sexually transmitted disease that threatens human health worldwide. However, the immune regulation cascade caused by treponemia pallidum (TP) infection remains still largely unclear. METHODS: To investigate the expression of ISGs in secondary syphilis (SS), we recruited 64 patients with SS and equal number of healthy participants to obtain their peripheral blood mononuclear cells (PBMCs). qRT-PCR was performed to estimate the expression of interferon-stimulated genes (ISGs) including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2. Receiver-operating characteristic (ROC) analysis was adapted to diagnostic value of these genes to distinguish healthy controls and patients with SS. RESULTS: ISGs including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2 were all upregulated in PBMCs of patients with SS. Area under the ROC curve (AUC) of the 8 ISGs were all more than 0.5. IFIT3 exhibited the highest diagnostic value, followed by AIM2, IFIT2 and CXCL10, according to the Yoden Index. CONCLUSION: ISGs including CXCL10, OAS3, OAS1, MX1, IFIT3, IFIT2, IFI6 and AIM2 were upregulated in patients with SS and they have diagnostic value for syphilis.


Assuntos
Interferons/metabolismo , Leucócitos Mononucleares/metabolismo , Sífilis/genética , Regulação para Cima , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sífilis/microbiologia , Adulto Jovem
10.
ACS Appl Mater Interfaces ; 13(28): 33237-33243, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34252274

RESUMO

At present, the studies on magnetocaloric properties are mainly based on polycrystalline materials, which is not enough to reveal and understand the origin of their magnetocaloric effect. In addition, finding new room temperature magnetocaloric materials is crucial to the development and application for room temperature magnetic refrigeration. Here, we report the magnetic transitions, magnetic anisotropy, and magnetocaloric properties of single-crystal Mn5Ge3 and Mn5Ge3/Mn3.5Fe1.5Ge3 heterostructures with six (100) surfaces and the [001] growth direction prepared using the Sn flux method. Mn5Ge3 (Mn3.5Fe1.5Ge3) undergoes a sharp paramagnetic-collinear ferromagnetic transition at 299 (332) K and weak collinear-noncollinear ferromagnetic transition at 65 (35) K. Owing to the distinct spin arrangements and magnetic moments of Mn5Ge3 and Mn3.5Fe1.5Ge3, the magnetic anisotropy of the single crystal is stronger than that of the heterostructure below 299 K. Moreover, a large anisotropic magnetocaloric effect, wide operating temperature range, and large refrigeration capacity near room temperature are obtained in these two materials, especially the magnetocaloric effect of the heterostructure presents a tablelike shape due to the adjacent paramagnetic-collinear ferromagnetic transitions of Mn5Ge3 and Mn3.5Fe1.5Ge3. Under 0-3 T, the maximum magnetic entropy change, operating temperature range, and refrigeration capacity of the single crystal (heterostructure) are 5.19 (2.96) J kg-1 K-1, 43 (57) K, and 223 (169) J kg-1 when H//c, respectively. These features make them candidates for room temperature magnetic refrigeration.

11.
Inorg Chem ; 60(7): 4883-4890, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33711893

RESUMO

One-dimensional materials have been intensively studied because of their diverse properties, which are revealed when exfoliated from their bulk precursor. Liquid exfoliation is not only possibly the most suitable method for large-scale applications but also affords an opportunity to develop new deposition techniques. Fibrous phosphorus is a relatively new, one-dimensional material with high carrier mobility and a fast response velocity for future application in nanodevices. Because controllable liquid exfoliation processing of fibrous phosphorus (FP) remains challenging, we considered two factors: the exfoliated result and the removable solvents. We proposed a method for determining suitable solvents for efficient exfoliation and controllable size of fibrous phosphorus using Hansen solubility parameters. By controlling the water/acetone mixture ratios, the exfoliation effect could be controlled. Our work showed that 40% of the FP nanofibers were less than 10 nm in thickness and 70% of them were less than 20 nm. Furthermore, fibrous phosphorus produced a red fluorescence in bioimaging.


Assuntos
Nanofibras/química , Fósforo/química , Humanos , Células MCF-7 , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
12.
Angew Chem Int Ed Engl ; 60(7): 3773-3780, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33174369

RESUMO

The effective non-precious metal catalysts toward the oxygen evolution reaction (OER) are highly desirable for electrochemical water splitting. Herein, we prepare a novel glass-ceramic (Ni1.5 Sn@triMPO4 ) by embedding crystalline Ni1.5 Sn nanoparticles into amorphous trimetallic phosphate (triMPO4 ) matrix. This unique crystalline-amorphous nanostructure synergistically accelerates the surface reconstruction to active Ni(Fe)OOH, due to the low vacancy formation energy of Sn in glass-ceramic and high adsorption energy of PO4 3- at the VO sites. Compared to the control samples, this dual-phase glass-ceramic exhibits a remarkably lowered overpotential and boosted OER kinetics after surface reconstruction, rivaling most of state-of-the-art electrocatalysts. The residual PO4 3- and intrinsic VO sites induce redistribution of electron states, thus optimizing the adsorption of OH* and OOH* intermediates on metal oxyhydroxides and promoting the OER activity.

13.
ACS Appl Mater Interfaces ; 12(35): 39245-39251, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32805876

RESUMO

Phase boundary movement accomplishing reversible LiFePO4/FePO4 biphasic transition is a fundamental Li-ion intercalation/deintercalation mechanism for LiFePO4 cathode. Phase boundary energetically favors crack nucleation and propagation; thus, postmortem observation on cracks becomes a feasible approach to investigate the phase-transition behavior and the Li-ion diffusion mechanism. The previously observed (200) plane cracks facilitate the "domino" diffusion model. Herein, our microscopic observations reveal another type of cracks along the (020) planes in a commercial LiFePO4 cathode cycled at moderate rates (0.1C, 0.33C, and 1C). Such (020) plane cracks are more detrimental to electrochemical performance because they can cut off the Li-ion diffusion pathway, causing inactive segments of LiFePO4. The (020) plane cracks indicate the LiFePO4/FePO4 phase boundary is along the (020) plane and moving along the b-axis during battery operation, which is a typical bulk diffusion-limited Li-ion diffusion behavior. Our observations stress that large LiFePO4 primary particle (>200 nm) not only aggravates cracking degradation but also switches the Li-ion diffusion mode to a slow bulk diffusion mechanism, plunging the overall battery performance.

14.
ACS Appl Mater Interfaces ; 12(21): 24125-24132, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32363848

RESUMO

Skyrmions with topologically nontrivial spin textures are promising information carriers in next-generation ultralow power consumption and high-density spintronic devices. To promote their further development and utilization, the search for new room temperature skyrmion-hosting materials is crucial. Considering that most of the previous skyrmion-hosting materials are noncollinear magnets, here, the detection of the topological Hall effect (THE) and the discovery of skyrmions at room temperature are first reported in a centrosymmetric complex noncollinear ferromagnet NdMn2Ge2. Below 330 K, the compound can host stable Bloch-type skyrmions with about 75 nm diameter in a wide window of magnetic field and temperature, including zero magnetic field and room temperature. Moreover, the skyrmions can induce a giant topological Hall effect in a wide temperature range with a maximum value of -2.05 µΩ cm. These features make the compound attractive for both fundamental research and potential application in novel spintronic devices.

15.
J Phys Chem Lett ; 11(9): 3436-3442, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32282220

RESUMO

Efficient electrocatalysts for the hydrogen evolution reaction (HER) are significant for the utilization of hydrogen as a fuel, particularly under alkaline conditions. However, the sluggish kinetics of HER remains a challenge. Here we demonstrate an efficient HER catalyst comprising Ru and AgCl nanoparticles anchored on Ag nanowires (Ru/AgCl@Ag), which delivers a low overpotential of 12 mV at 10 mA cm-2 and a Tafel slope of 38 mV decade-1. A high mass activity of 214 mA mg-1 at an overpotential of 25 mV and a long-term durability in 1.0 M KOH are observed. In combination with computational simulations, we find that the high electronegativity of chlorine in AgCl and d-band electrons from Ru synergistically destabilize the water molecule and modulate H adsorption/desorption on the surface of Ru/AgCl@Ag, respectively. This work opens a promising avenue for the facile design and application of highly active and stable composite electrocatalysts toward water splitting.

16.
Inorg Chem ; 59(2): 976-979, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31885252

RESUMO

Quasi-one-dimensional (Q1D) semiconductor materials, such as carbon nanotubes, SbSI, MP15 (M = Li, Na, K), and selenium and tellurium nanowires, show amazing potential for applications in future nanoelectronic and optoelectronic devices. However, intricate chirality in the structure of carbon nanotubes limits their applications. Also, the performance of MP15 in optoelectronics has yet to be extensively explored. One new Q1D semiconductor material, fibrous phosphorus (FP), has recently received attention because its raw material is less toxic. However, the ability to characterize FP by phase identification is limited in the assessment of micro/nano-thickness, such as exfibrated FP. So, identifying a precise Raman spectrum will allow for much better characterization. Here, a sufficiently sharp Raman spectrum of FP was obtained and analyzed. Moreover, we demonstrated that high-quality, few-layer FP fibers with thicknesses as low as 5.55 nm can be produced by liquid-phase exfibration under ambient conditions in solvents. More importantly, an optoelectronic detector based on a single FP fiber field-effect-transistor configuration was investigated. A rise time as short as about 40 ms was obtained for the FP transistors, illustrating the potential of FP single bundle crystals as a new one-dimensional material for optoelectronic device applications.

17.
ACS Nano ; 13(8): 8708-8716, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31318525

RESUMO

With continuous minimization of nanodevices, the dimensions of metallic materials used in nanodevices decrease to a few nanometers. Understanding the structural stability and deformation behavior of these small-sized metallic materials is important for their practical applications. Here we report our atomic-resolution observation of the deformation processes of Ag nanowires with widths of ∼3 nm. The nanowires under tension experienced plastic deformation via partial dislocation activities, which led to deformation twinning in and homogeneous elongation of the nanowires, and surface atom diffusion that reduced the nanowires' width but did not contribute to the nanowire elongation. The diffusion of surface atoms was initiated at surface steps introduced by the partial dislocation activities, leading to fracture of the nanowires with relatively low homogeneous elongation.

18.
Sci Bull (Beijing) ; 64(8): 553-561, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36659746

RESUMO

The mechanism research of structure-related reactions on Li2MnO3 is important to enhance the electrochemical performance of lithium-manganese-rich layered oxides. Although there are some reports on the structure evolution of Li2MnO3 during cycling process, the employed research techniques are very limited, mainly in/ex-situ X-ray diffraction, X-ray absorption and transmission electron microscopy. Here, atomic pair distribution function, a method to study the local atomic arrangement on the basis of average spectroscopic information, is used for the first time to study the local structure evolution of Li2MnO3 during electrochemical charge/discharge cycles. The results clearly demonstrate that Mn3+/Mn4+ redox couple is activated and Mn ions are reduced during discharging process. Some Mn ions in Mn layers can significantly migrate to Li layers and occupy the octahedral sites. As a result, a portion of inserted Li ions can occupy the face-shared tetrahedronsites, accompanied by the formation of local spinel-like structure. This work provides an important and suitable method based on the average spectroscopic information to investigate the local structure of electrode materials of lithium-ion batteries as well as other advanced battery systems.

19.
ACS Appl Mater Interfaces ; 10(37): 31136-31145, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30192124

RESUMO

Black phosphorus (BP) has attracted much attention as a new member of 2D materials due to its unique electronic and optical properties and a wide range of promising applications. Here, for the first time, we report the photoluminescence lifetime of BP nanomaterial and its applications as an efficient agent for live cell imaging. With a lateral size of ∼35 nm and a thickness of ∼6 nm, the fabricated BP nanoparticles (BPNPs) exhibited a unique photoluminescent (PL) emission at ∼690 nm. The photoluminescence lifetime (PLT) of BPNPs was determined to be 110.5 ps. Coating a layer of mesoporous silica on the surface of BPNPs (BPNPs@mSiO2) extended the lifetime to 267 ps, suggesting a change in the microenvironment. The lifetime was also influenced by ionic strength and intracellular microenvironment, which implies BPNPs as valuable probes for sensing variations in the microenvironment. Live cell imaging was achieved via directly probing the photoluminescence intensity or the photoluminescence lifetime. Our findings are significant, implying that BPNPs can be of large value in sensing variations of the cellular microenvironment and in probing cells with distinct cytosolic contents. This research leads to promising prospects for BPNPs in multiple biomedical applications.


Assuntos
Técnicas Citológicas/métodos , Luminescência , Nanopartículas/química , Imagem Óptica/métodos , Fósforo/química , Luz , Dióxido de Silício/química , Fatores de Tempo
20.
Nanoscale ; 10(35): 16479-16484, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30155528

RESUMO

We studied the excitonic states of KP15 nanowires, which have high carrier mobility and in-plane anisotropic electrical and optical properties. Power, thickness, and temperature-dependent photoluminescence (PL) measurements were carried out. We found two neutral exciton emissions from KP15 nanowires. The high energy emission (1.83 eV) seems to have been produced by the surface state, and the lower one (1.67 eV) may have been produced by the original crystal structure of KP15. The KP15 nanowires also exhibited a large exciton binding energy (98 meV), which is one order of magnitude greater than those of common semiconductors. These properties make KP15 nanowires an interesting material for electrical and optical applications.

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