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1.
Rev Sci Instrum ; 95(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38165821

RESUMO

We present a detailed exposition of the design for time- and angle-resolved photoemission spectroscopy using a UV probe laser source that combines the nonlinear effects of ß-BaB2O4 and KBe2BO3F2 optical crystals. The photon energy of the probe laser can be switched between 6.0 and 7.2 eV, with the flexibility to operate each photon energy setting under two distinct resolution configurations. Under the fully optimized energy resolution configuration, we achieve an energy resolution of 8.5 meV at 6.0 eV and 10 meV at 7.2 eV. Alternatively, switching to the other configuration enhances the temporal resolution, yielding a temporal resolution of 72 fs for 6.0 eV and 185 fs for 7.2 eV. We validated the performance and reliability of our system by applying it to measuring two typical materials: the topological insulator MnBi2Te4 and the excitonic insulator candidate Ta2NiSe5.

2.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081257

RESUMO

Time-resolved and angle-resolved photoemission spectroscopy (trARPES) is a powerful method to detect the non-equilibrium electronic structure in solid systems. In this study, we report a trARPES apparatus with tunable photon energy selectively among 12, 16.8, and 21.6 eV at a repetition rate of 400 kHz. The energy and temporal resolutions of the three harmonics are determined as 104/111/157 meV and 276/190/154 fs, respectively. The photon flux on the sample is estimated to be 1010-1011 photons/s by using a photodiode. Finally, the performance of this setup is verified by both equilibrium and non-equilibrium ARPES measurements on topological materials Zr2Te2P and Bi2Se3. Meanwhile, the importance of the tunability of the extreme ultraviolet (XUV) source is highlighted by comparing experimental results measured with the three different photon energies.

3.
Nat Commun ; 14(1): 7012, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919285

RESUMO

The search for topological superconductivity (TSC) is currently an exciting pursuit, since non-trivial topological superconducting phases could host exotic Majorana modes. However, the difficulty in fabricating proximity-induced TSC heterostructures, the sensitivity to disorder and stringent topological restrictions of intrinsic TSC place serious limitations and formidable challenges on the materials and related applications. Here, we report a new type of intrinsic TSC, namely intrinsic surface topological superconductivity (IS-TSC) and demonstrate it in layered AuSn4 with Tc of 2.4 K. Different in-plane and out-of-plane upper critical fields reflect a two-dimensional (2D) character of superconductivity. The two-fold symmetric angular dependences of both magneto-transport and the zero-bias conductance peak (ZBCP) in point-contact spectroscopy (PCS) in the superconducting regime indicate an unconventional pairing symmetry of AuSn4. The superconducting gap and surface multi-bands with Rashba splitting at the Fermi level (EF), in conjunction with first-principle calculations, strongly suggest that 2D unconventional SC in AuSn4 originates from the mixture of p-wave surface and s-wave bulk contributions, which leads to a two-fold symmetric superconductivity. Our results provide an exciting paradigm to realize TSC via Rashba effect on surface superconducting bands in layered materials.

4.
J Gastrointest Oncol ; 14(4): 1830-1836, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37720451

RESUMO

Background: Compared to hepatic artery infusion chemotherapy (HAIC) treatment through the femoral artery (TFA), the brachial artery (TBA) is more flexible and easier for patients to accept. However, the feasibility of TBA has not been studied yet. This study aims to evaluate the feasibility and safety of HAIC via the TBA. Methods: We retrospectively reviewed the medical records of 63 patients with primary liver cancer who were treated with HAIC via TBA. In this study, a total of 163 HAIC procedures were performed via the left brachial artery pathway, and each patient underwent an average of 2.59 procedures. One patient received 5 treatments, 18 patients received 4 treatments, 15 patients received 3 treatments, 12 patients received 2 treatments, and 17 patients received 1 treatment. The main evaluation indicators were the technical success rate and complication rate. Results: The main technical success rate was 99.4% (162/163). No patient required conversion to the femoral artery (TFA) access. All the complications were minor and occurred in 11 patients (6.75%). Subcutaneous ecchymosis occurred in 3 (1.84%) patients, arterial thrombosis in 2 patients (1.23%), and catheter displacement in 6 patients (3.68%). No serious complications occurred. Conclusions: TBA pathway is feasible and safe for HAIC treatment of liver cancer patients. More research is needed in the future to confirm whether TBA is superior to other pathways.

5.
Opt Express ; 31(6): 9854-9871, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157547

RESUMO

High-order harmonic generation (HHG) has a broad spectrum covering vacuum ultraviolet to extreme ultraviolet (XUV) bands, which is useful for applications involving material analyses at different information depths. Such an HHG light source is perfect for time- and angle-resolved photoemission spectroscopy. Here, we demonstrate a high-photon flux HHG source driven by a two-color field. Applying a fused silica compression stage to reduce the driving pulse width, we obtained a high XUV photon flux of 2 × 1012 phs/s @21.6 eV on target. We designed a classical diffraction mounted (CDM) grating monochromator that can achieve a wide range of photon energy from 12 to 40.8 eV, while the time resolution is improved by reducing the pulse front tilt after the harmonic selection. We designed a spatial filtering method to adjust the time resolution using the CDM monochromator and significantly reduced the pulse front tilt of the XUV pulses. We also demonstrate a detailed prediction of the energy resolution broadening which is caused by the space charge effect.

6.
Materials (Basel) ; 15(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35897572

RESUMO

This study investigated the anti-corrosion performance of commercial amino alcohol migratory corrosion inhibitors (MCIs) on concrete that underwent varying degrees of chloride erosion. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PD), scanning electron microscopy, and energy dispersive spectroscopy (SEM-EDS) analyses were performed to study the anti-corrosion performance and mechanism of the MCIs on the steel bars. The results indicated that the corrosion resistance of the steel bars in concrete was significantly improved by coating with the MCIs, and the earlier the specimens were coated with the MCIs, the higher the anti-corrosion efficiency. The anti-corrosion efficiency was 55.35% when the MCIs coating was applied before chloride erosion; however, the anti-corrosion efficiency decreased to 3.40% when the MCIs coating was applied after the ninth drying-wetting cycle. The improvement in corrosion resistance of the steel bar in concrete coated with MCIs was due to the protective MCIs-molecule film that formed on the steel bar surfaces, and the oxidative dissolution of iron at the anode was effectively inhibited by the MCIs coating.

7.
Exp Ther Med ; 14(6): 5678-5686, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29285110

RESUMO

Cell-based adoptive immunotherapy for the treatment of various cancer types has attracted the attention of scientists. However, due to the absence of unitary standard protocols to produce large quantities of clinical-grade effector cells, it remains challenging to translate the experimental findings into clinical applications. The present study used methods complying with good manufacturing practice to induce effector cells from human peripheral blood mononuclear cells (PBMCs) of healthy donors by interleukin-2 and anti-Her-2 antibody with or without anti-CD3 antibodies (OKT3). The results indicated that the addition of OKT3 resulted in a greater expansion of the total cells and CD8+ T cells, and primarily induced the PBMCs to differentiate into CD3+ T cells. Regardless of the presence of OKT3, the expression of activating receptor of natural killer (NK) group 2, member D, and the inhibitory receptors of CD158a and CD158b on NK cells and NKT cells was increased, while the expression of NKp46 was inhibited on NK cells, but not on NKT cells. Furthermore, OKT3 did not affect the toxicity of the effector cells. Subgroup analysis indicated that although a variation of the composition of effector cells was present in different individuals under identical culture conditions, consistent marker expression on effector cells and target cell-killing effects were observed in different subgroups treated with or without OKT3. Furthermore, western blot analysis indicated that OKT3, apart from its involvement in cell cycle regulation, affects transcription and protein translation during processes of proliferation and differentiation. The present study provided experimental data regarding the production of effector cells for adoptive immunotherapy as a clinical application.

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