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1.
ChemSusChem ; : e202301807, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847187

RESUMO

Sn and C nanocomposites are ideal anode materials for high-energy and high-power density lithium ion batteries. However, their facile and controllable synthesis for practical applications is still a critical challenge. In this work, a facile one-step method is developed to controllably synthesize ultrafine Sn nanocrystals (< 5 nm) loaded on carbon black (Sn@C) through Na reducing SnCl4 by mechanical milling. Different from traditional up-down mechanical milling method, this method utilizes mechanical milling to trigger bottom-up reduction reaction of SnCl4. The in-situ formed Sn nanocrystals directly grow on carbon black, which results in the homogeneous composite and the size control of Sn nanocrystals. The obtained Sn@C electrode is revealed to possesses large lithium diffusion coefficient, low lithiation energy barrier and stable electrochemical property during cycle, thus showing excellent lithium storage performance with a high reversible capacity (942 mAh g-1 at a current density of 100 mA g-1), distinguished rate ability (480 mAh g-1 at 8000 mA g-1) and superb cycling performance (730 mAh g-1 at 1000 mA g-1 even after 1000 cycles).

2.
Chin J Nat Med ; 22(5): 402-415, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38796214

RESUMO

In the realm of autoimmune and inflammatory diseases, the cyclic GMP-AMP synthase (cGAS) stimulator of interferon genes (STING) signaling pathway has been thoroughly investigated and established. Despite this, the clinical approval of drugs targeting the cGAS-STING pathway has been limited. The Total glucosides of paeony (TGP) is highly anti-inflammatory and is commonly used in the treatment of rheumatoid arthritis (RA), emerged as a subject of our study. We found that the TGP markedly reduced the activation of the cGAS-STING signaling pathway, triggered by various cGAS-STING agonists, in mouse bone marrow-derived macrophages (BMDMs) and Tohoku Hospital Pediatrics-1 (THP-1) cells. This inhibition was noted alongside the suppression of interferon regulatory factor 3 (IRF3) phosphorylation and the expression of interferon-beta (IFN-ß), C-X-C motif chemokine ligand 10 (CXCL10), and inflammatory mediators such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). The mechanism of action appeared to involve the TGP's attenuation of the STING-IRF3 interaction, without affecting STING oligomerization, thereby inhibiting the activation of downstream signaling pathways. In vivo, the TGP hindered the initiation of the cGAS-STING pathway by the STING agonist dimethylxanthenone-4-acetic acid (DMXAA) and exhibited promising therapeutic effects in a model of acute liver injury induced by lipopolysaccharide (LPS) and D-galactosamine (D-GalN). Our findings underscore the potential of the TGP as an effective inhibitor of the cGAS-STING pathway, offering a new treatment avenue for inflammatory and autoimmune diseases mediated by this pathway.


Assuntos
Glucosídeos , Fator Regulador 3 de Interferon , Proteínas de Membrana , Nucleotidiltransferases , Paeonia , Transdução de Sinais , Fator Regulador 3 de Interferon/metabolismo , Animais , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Glucosídeos/farmacologia , Camundongos , Humanos , Paeonia/química , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Transdução de Sinais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Células THP-1
3.
Sci Rep ; 14(1): 9340, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654052

RESUMO

High voltage circuit breakers are one of the core equipment in power system operation, and the voiceprint signals generated during operation contain extremely rich information. This paper proposes a fault identification method for high voltage circuit breakers based on voiceprint information data. Firstly, based on the developed voiceprint information data acquisition device, the voiceprint information of a certain high voltage circuit breaker is obtained; Secondly, an improved S-transform is proposed in the article, which generates an amplitude matrix based on the S-transform of voiceprint information; Then, through the matrix Singular value decomposition method, the fault feature quantity of voiceprint information is extracted from the time-frequency angle, and the diagnosis system of the support vector machine model is established, and the system is trained to realize the fault identification of the high-voltage circuit breaker; Finally, through experimental simulation calculations, it was shown that the accuracy of the proposed fault identification method in different operating conditions reached 92.6%, verifying the good accuracy and robustness of the proposed method and equipment.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38465433

RESUMO

INTRODUCTION: Lenvatinib resistance causes less than 40% of the objective response rate. Therefore, it is urgent to explore new therapeutic targets to reverse the lenvatinib resistance for HCC. HAND2-AS1 is a critical tumor suppressor gene in various cancers. METHODS: Here, we investigated the role of HAND2-AS1 in the molecular mechanism of lenvatinib resistance in HCC. It was found that HAND2-AS1 was lowly expressed in the HepG2 lenvatinib resistance (HepG2-LR) cells and HCC tissues and associated with progression-free intervals via TCGA. Overexpression of HAND2-AS1 (OE-HAND2-AS1) decreased the IC50 of lenvatinib in HepG2-LR cells to reverse lenvatinib resistance. Moreover, OE-HAND2-AS1 induced intracellular concentrations of malondialdehyde (MDA) and lipid ROS and decreased the ratio of glutathione to glutathione disulfide (GSH/GSSG) to promote ferroptosis. RESULTS: A xenograft model in which nude mice were injected with OE-HAND2-AS1 HepG2-LR cells confirmed that OE-HAND2-AS1 could reverse lenvatinib resistance and decrease tumor formation in vivo. HAND2-AS1 promoted the expression of ferroptosis-related genes (TLR4, NOX2, and DUOX2) and promoted ferroptosis to reverse lenvatinib resistance by increasing TLR4/ NOX2/DUOX2 via competing endogenous miR-219a-1-3p in HCC cells. Besides, patients with a low HAND2-AS1 level had early recurrence after resection. CONCLUSION: These findings suggested that HAND2-AS1 may be a potential therapeutic target and an indicator of early recurrence for HCC.

5.
Clin Transl Gastroenterol ; 15(2): e00662, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38099588

RESUMO

INTRODUCTION: Liver fibrosis results from chronic liver injury and inflammation, often leading to cirrhosis, liver failure, portal hypertension, and hepatocellular carcinoma. Progress has been made in understanding the molecular mechanisms underlying hepatic fibrosis; however, translating this knowledge into effective therapies for disease regression remains a challenge, with considerably few interventions having entered clinical validation. The roles of exosomes during fibrogenesis and their potential as a therapeutic approach for reversing fibrosis have gained significant interest. This study aimed to investigate the association between microRNAs (miRNAs) derived from serum exosomes and liver fibrosis and to evaluate the effect of serum exosomes on fibrogenesis and fibrosis reversal, while identifying the underlying mechanism. METHODS: Using serum samples collected from healthy adults and paired histologic patients with advanced fibrosis or cirrhosis, we extracted human serum exosomes by ultrahigh-speed centrifugation. Transcriptomic analysis was conducted to identify dysregulated exosome-derived miRNAs. Liver fibrosis-related molecules were determined by qRT-PCR, Western blot, Masson staining, and immunohistochemical staining. In addition, we analyzed the importance of serum exosome-derived miRNA expression levels in 42 patients with advanced fibrosis or cirrhosis. RESULTS: Exosome-derived miR-193a-5p and miR-381-3p were associated with fibrogenesis, as determined by transcriptomic screening. Compared with healthy control group, the high expression of serum exosome-derived miR-193a-5p and miR-381-3 in chronic hepatitis B (n = 42) was closely associated with advanced liver fibrosis and cirrhosis. In vitro , exosome-derived miRNA-193a-5p and miR-381-3p upregulated the expression of α-smooth muscle actin, collagen 1a1, and tissue inhibitors of metalloproteinase 1 in the human hepatic stellate cell line at both mRNA and protein levels. DISCUSSION: Serum exosome-derived miR-193a-5p and miR-381-3p regulated the adenosine 5'-monophosphate-activated protein kinase/transforming growth factor beta/Smad2/3 signaling pathway and promoted fibrogenesis.


Assuntos
Exossomos , MicroRNAs , Adulto , Humanos , Proteínas Quinases/metabolismo , Proteínas Quinases/farmacologia , Exossomos/genética , Exossomos/metabolismo , Exossomos/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Transdução de Sinais , Cirrose Hepática/patologia , Fator de Crescimento Transformador beta/metabolismo , Adenosina/metabolismo , Adenosina/farmacologia
6.
Phys Chem Chem Phys ; 25(46): 32051-32061, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37982198

RESUMO

The reaction pathways and potential energy profiles are theoretically explored for H-abstraction, addition and addition-dissociation reactions of methyl formate (MF, HC(O)OCH3) + NO2 using the high level quantum chemical compound method CCSD(T)/cc-pVxZ(x = T, Q)//M062X/6-311+G(2df,2p). Notably, three different HNO2 isomers (cis-HONO, trans-HONO and HNO2) are all considered in each reaction pathway. The corresponding temperature- and pressure-dependent rate constants are then computed by RRKM/ME simulations with one-dimensional hindered rotor approximation and asymmetric Eckart tunneling corrections. The calculations show that the rate constants are pressure independent. Although trans-HONO is the most stable HNO2 isomer, the results reveal that the dominant channels are cis-HONO + HC(O)OCH2/C(O)OCH3 and cis-HC(O)(ONO)OCH3 for the H-abstraction and addition, respectively. Moreover, the lowest energy barrier for the H-abstraction channel (cis-abs) is 11.2 kcal mol-1 lower than the addition channel (cis-add), and thus the addition channel is less kinetically favored. The computed rate constants for the MF + NO2 reaction are then incorporated into a kinetic model and the importance of the title reaction in predicting the ignition behavior of MF/NO2 mixtures is demonstrated by kinetic modeling. The detailed reaction kinetics in this work will be helpful for kinetic model development of other ester-based fuels.

7.
Respir Res ; 24(1): 165, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344798

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is a rare but fatal cardiopulmonary disease mainly characterized by pulmonary vascular remodeling. Aberrant expression of circRNAs has been reported to play a crucial role in pulmonary vascular remodeling. The existing literature predominantly centers on studies that examined the sponge mechanism of circRNAs. However, the mechanism of circRNAs in regulating PAH-related protein remains largely unknown. This study aimed to investigate the effect of circItgb5 on pulmonary vascular remodeling and the underlying functional mechanism. MATERIALS AND METHODS: High-throughput circRNAs sequencing was used to detect circItgb5 expression in control and PDGF-BB-treated pulmonary arterial smooth muscle cells (PASMCs). Localization of circItgb5 in PASMCs was determined via the fluorescence in situ hybridization assay. Sanger sequencing was applied to analyze the circularization of Itgb5. The identification of proteins interacting with circItgb5 was achieved through a RNA pull-down assay. To assess the impact of circItgb5 on PASMCs proliferation, an EdU assay was employed. Additionally, the cell cycle of PASMCs was examined using a flow cytometry assay. Western blotting was used to detect biomarkers associated with the phenotypic switch of PASMCs. Furthermore, a monocrotaline (MCT)-induced PAH rat model was established to explore the effect of silencing circItgb5 on pulmonary vascular remodeling. RESULTS: CircItgb5 was significantly upregulated in PDGF-BB-treated PASMCs and was predominately localized in the cytoplasm of PASMCs. In vivo experiments revealed that the knockdown of circItgb5 attenuated MCT-induced pulmonary vascular remodeling and right ventricular hypertrophy. In vitro experiments revealed that circItgb5 promoted the transition of PASMCs to synthetic phenotype. Mechanistically, circItgb5 sponged miR-96-5p to increase mTOR level and interacted with Uba1 protein to activate the Ube2n/Mdm2/ACE2 pathway. CONCLUSIONS: CircItgb5 promoted the transition of PASMCs to synthetic phenotype by interacting with miR-96-5p and Uba1 protein. Knockdown of circItgb5 mitigated pulmonary arterial pressure, pulmonary vascular remodeling and right ventricular hypertrophy. Overall, circItgb5 has the potential for application as a therapeutic target for PAH.


Assuntos
Hipertensão Pulmonar , Cadeias beta de Integrinas , RNA Circular , Animais , Masculino , Ratos , Células Cultivadas , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , MicroRNAs/metabolismo , Monocrotalina , Mioblastos de Músculo Liso/metabolismo , Proteínas Proto-Oncogênicas c-sis , Ratos Sprague-Dawley , RNA Circular/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima , Remodelação Vascular , Cadeias beta de Integrinas/genética
8.
Nat Commun ; 14(1): 1718, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977681

RESUMO

Rare earth emitters enable critical quantum resources including spin qubits, single photon sources, and quantum memories. Yet, probing of single ions remains challenging due to low emission rate of their intra-4f optical transitions. One feasible approach is through Purcell-enhanced emission in optical cavities. The ability to modulate cavity-ion coupling in real-time will further elevate the capacity of such systems. Here, we demonstrate direct control of single ion emission by embedding erbium dopants in an electro-optically active photonic crystal cavity patterned from thin-film lithium niobate. Purcell factor over 170 enables single ion detection, which is verified by second-order autocorrelation measurement. Dynamic control of emission rate is realized by leveraging electro-optic tuning of resonance frequency. Using this feature, storage, and retrieval of single ion excitation is further demonstrated, without perturbing the emission characteristics. These results promise new opportunities for controllable single-photon sources and efficient spin-photon interfaces.

9.
J Colloid Interface Sci ; 630(Pt A): 204-211, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242880

RESUMO

Aluminum sulfide is a novel light metal sulfide, which possesses multiple advantages for lithium storage, including high theoretical capacity, proper discharge potential and good conductivity. However, much research has not been done in areas related to light metal sulfide materials. Herein, we synthesized Al2S3/C nanocomposite by a facile one-step ball milling method. This simple method not only effectively achieves the uniform composite of Al2S3 nanoparticles and carbon sheets, but also controls Al2S3 into ultrafine nanocrystals. Al2S3/C electrode demonstrates very outstanding lithium storage performance with large reversible specific capacity (1249 mAh g-1 at 100 mA g-1), remarkable rate capability (670 mAh g-1 at 5000 mA g-1) and superior long-cycling stability (retaining 850 mAh g-1 even after 1000 cycles at 1000 mA g-1). Moreover, the reversible lithium storage behavior and excellent diffusion kinetics of Al2S3/C are unveiled deeply. This work provides an inspiration to develop new light metal sulfide materials for the next-generation high-performance lithium ion battery.

10.
ACS Omega ; 7(11): 9267-9275, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350369

RESUMO

Two-dimensional materials with excellent surface-volume ratios and massive reaction sites recently have been receiving attention for gas sensing. With first-principles calculations, we explored the performance of monolayer Sc2CF2 as a gas sensor. We investigated how molecule adsorption affects its electronic structure and optical properties. It is found that a large charge transfer quantity happens between Sc2CF2 and NO2, which results from the fact that the lowest unoccupied molecular orbital (LUMO) of NO2 is below the valence band maximum (VBM) of Sc2CF2. Moreover, the MD simulation shows that NO2 can adsorb on the Sc2CF2 surface stably at room temperature. We explored the effect of biaxial strain on the adsorption energy and charge transfer quantity of each system, and the results show that the biaxial strain can enhance both the adsorption energy and charge transfer quantity of the NO2 system and thus can improve the sensitivity of Sc2CF2 in detecting the NO2 molecule. Furthermore, we investigated the adsorption behavior and charge transfer of polar polyatomic molecules at the Sc2CF2 surface with h-BN as a substrate, and the results demonstrate that the h-BN substrate can hardly modify the main results. Our result predicts that Sc2CF2 can be a promising selective and sensitive sensor to detect the NO2 molecule, and could also give a theoretical guide for other terminated MXenes used for gas sensors or detectors.

11.
Nat Commun ; 12(1): 4453, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294711

RESUMO

Superconducting cavity electro-optics presents a promising route to coherently convert microwave and optical photons and distribute quantum entanglement between superconducting circuits over long-distance. Strong Pockels nonlinearity and high-performance optical cavity are the prerequisites for high conversion efficiency. Thin-film lithium niobate (TFLN) offers these desired characteristics. Despite significant recent progresses, only unidirectional conversion with efficiencies on the order of 10-5 has been realized. In this article, we demonstrate the bidirectional electro-optic conversion in TFLN-superconductor hybrid system, with conversion efficiency improved by more than three orders of magnitude. Our air-clad device architecture boosts the sustainable intracavity pump power at cryogenic temperatures by suppressing the prominent photorefractive effect that limits cryogenic performance of TFLN, and reaches an efficiency of 1.02% (internal efficiency of 15.2%). This work firmly establishes the TFLN-superconductor hybrid EO system as a highly competitive transduction platform for future quantum network applications.

12.
Opt Express ; 29(10): 15497-15504, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985248

RESUMO

Rare earth ions are known as promising candidates for building quantum light-matter interface. However, tunable photonic cavity access to rare earth ions in their desired host crystal remains challenging. Here, we demonstrate the integration of erbium doped yttrium orthosilicate (Er3+:Y2SiO5) with thin-film lithium niobate photonic circuit by plasma-activated direct flip chip bonding. Resonant coupling to erbium ions is realized by on-chip electro-optically tuned high Q lithium niobate micro-ring resonators. Fluorescence and absorption of erbium ions at 1536.48 nm are measured in the waveguides, while the collective ion-cavity cooperativity with micro-ring resonators is assessed to be 0.36. This work presents a versatile scheme for future rare earth ion integrated quantum devices.

13.
ACS Appl Mater Interfaces ; 13(1): 827-835, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33370090

RESUMO

Constructing robust and cost-effective Pt-based electrocatalysts with an easily operated strategy remains a crucial obstacle to fuel cell applications. Conventional Pt-based catalysts suffer from high Pt content and an arduous synthetic process. Herein, through the spray dehydration method and annealing treatment, facile producible synthesis of a small-sized (5.2 nm) low-Pt (10.5 wt %) ordered PtCo3/C catalyst (O-PtCo3/C) for oxygen reduction reaction is reported. The fast spray evaporation rate contributes to small size and uniform nucleation of nanoparticles (NPs) on carbon support. O-PtCo3/C-600 exhibits efficient electrocatalytic performance with mass activity (MA) 6.0-fold and specific activity 3.9-fold higher than commercial Pt/C. The ordered chemical structure generates superior stability with merely 3.5% decay in MA after 10,000 potential cycles. Density functional theory calculations reveal that the enhanced catalytic performance originates from rational modification of d-band through strain and ordering effect and accompanying weaker adsorption of intermediate OH. This work highlights the potentials of low-Pt PtM3-type ordered NPs for prospective fuel cell cathodic catalysis. The proposed facile and practical synthetic strategy also shows promising prospects for preparing effective Pt-based electrocatalysts.

14.
Opt Lett ; 45(20): 5872-5875, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057306

RESUMO

Nanoscale refractive index (RI) sensors based on plasmonic structures usually suffer from a low figure of merit (FoM) due to the broad linewidth of the resonance peaks. Here, we report a magnetoplasmon-based RI sensing method with high FoM in the designed H-shaped magnetoplasmonic crystals. Instead of the light intensity spectrum, the Faraday signal is detected to analyze the changes of the surrounding RI. Sharp resonance with extremely narrow linewidth is obtained by plotting the reciprocal Faraday rotation near the null point region. Therefore, the FoM is hugely enhanced, and a theoretical value exceeding 1775/RIU is achieved, which is one order of magnitude higher than has ever been reported, to the best of our knowledge, for the RI sensor based on the Faraday effect. The Faraday reversal and the enhanced FoM arise from the Fano resonance. These findings are of potential value for practical high performance biochemical sensors.

15.
Nanotechnology ; 31(45): 455605, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-32746441

RESUMO

Structurally ordered Pt3Co/C nanoparticles (NPs) were obtained via a spray paint drying method with an annealing treatment. The addition of a suitable dose of polyvinylpyrrolidone resulted in a narrow size distribution of the Pt3Co/C-600-1 NPs, an average particle size of ca. 4.6 nm, which may be due to the enhanced dispersion in aqueous solution resulting from the carbon support. The sample denoted as Pt3Co/C-600-1 NPs performs high activity for oxygen reduction reaction with the mass activity (MA) ca. 3 times higher than that of a commercial Pt/C catalyst at 0.9 V. Accelerated durability tests (ADTs) showed that Pt3Co/C-600-1 NPs exhibit superior stability with a minimal loss of 17.5% in MA at 0.9 V after 5000 cycles, while Pt/C catalysts show loss of 44.4%. This simple two-step strategy provides an effective way to prepare Pt-based catalysts for industrial application.

16.
Nat Commun ; 11(1): 3237, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591510

RESUMO

Hybrid quantum systems are essential for the realization of distributed quantum networks. In particular, piezo-mechanics operating at typical superconducting qubit frequencies features low thermal excitations, and offers an appealing platform to bridge superconducting quantum processors and optical telecommunication channels. However, integrating superconducting and optomechanical elements at cryogenic temperatures with sufficiently strong interactions remains a tremendous challenge. Here, we report an integrated superconducting cavity piezo-optomechanical platform where 10 GHz phonons are resonantly coupled with photons in a superconducting cavity and a nanophotonic cavity at the same time. Taking advantage of the large piezo-mechanical cooperativity (Cem ~7) and the enhanced optomechanical coupling boosted by a pulsed optical pump, we demonstrate coherent interactions at cryogenic temperatures via the observation of efficient microwave-optical photon conversion. This hybrid interface makes a substantial step towards quantum communication at large scale, as well as novel explorations in microwave-optical photon entanglement and quantum sensing mediated by gigahertz phonons.

17.
ACS Omega ; 4(18): 17894-17902, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31681899

RESUMO

Synthesis of electrocatalysts for oxygen reduction reaction (ORR) with not only prominent electrocatalytic performance but also a low amount of Pt is the urgent challenge in the popularization of fuel cells. In this work, through a facile synthetic strategy of spray dehydration on a solid surface and annealing process, we demonstrate the first manufacture of quaternary structurally ordered PtM3 (M = transition metal) intermetallic nanoparticles (NPs), Pt(Fe, Co, Ni)3, in order to lower the content of Pt. The atomic contents of Pt, Fe, Co, and Ni are equal and the chemical structure of Pt(Fe, Co, Ni)3 is a cubic L12-ordered structure. L12-Pt(Fe, Co, Ni)3/C electrocatalysts exhibit enhanced electrocatalytic performance toward ORR with mass activity (MA) 6.6 times higher than the commercial Pt/C and a minimal loss of 17% in MA and 1.5% loss in specific activity (SA) after 10 000 potential cycles at 0.9 V. Furthermore, the stability behavior is confirmed to be attributed to the coaction of particle sizes and the ordering effect. Compared with traditional Pt-based electrocatalysts in the stoichiometric forms of Pt3M and PtM, L12-Pt(Fe, Co, Ni)3 intermetallic NPs exhibit excellent performance and higher cost effectiveness. Moreover, this work also proposes a facile and effective synthetic strategy for manufacturing multicomponent Pt-based electrocatalysts for ORR.

18.
Nat Commun ; 10(1): 4104, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506440

RESUMO

Single-photon counters are single-pixel binary devices that click upon the absorption of a photon but obscure its spectral information, whereas resolving the color of detected photons has been in critical demand for frontier astronomical observation, spectroscopic imaging and wavelength division multiplexed quantum communications. Current implementations of single-photon spectrometers either consist of bulky wavelength-scanning components or have limited detection channels, preventing parallel detection of broadband single photons with high spectral resolutions. Here, we present the first broadband chip-scale single-photon spectrometer covering both visible and infrared wavebands spanning from 600 nm to 2000 nm. The spectrometer integrates an on-chip dispersive echelle grating with a single-element propagating superconducting nanowire detector of ultraslow-velocity for mapping the dispersed photons with high spatial resolutions. The demonstrated on-chip single-photon spectrometer features small device footprint, high robustness with no moving parts and meanwhile offers more than 200 equivalent wavelength detection channels with further scalability.

19.
Opt Lett ; 43(20): 5090-5093, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30320827

RESUMO

The sensing performance of one-dimensional magnetic nanograting based on magnetoplasmons was investigated. The predictable Kerr reversal and enhancement are achieved in our experiment. The further result shows that the shift of the Kerr null point has a linear relationship with the surrounding refractive index in a wide range. In addition, a huge figure of merit (FoM) of 1728/refractive index unit is achieved, which is 1 order of magnitude higher than the results reported. The experiment and theory confirm that the excitation of surface plasmons leads to the Kerr reversal and enhancement, resulting in a huge FoM.

20.
Sci Adv ; 4(8): eaar4994, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30128351

RESUMO

Leveraging the quantum information-processing ability of superconducting circuits and long-distance distribution ability of optical photons promises the realization of complex and large-scale quantum networks. In such a scheme, a coherent and efficient quantum transducer between superconducting and photonic circuits is critical. However, this quantum transducer is still challenging because the use of intermediate excitations in current schemes introduces extra noise and limits bandwidth. We realize direct and coherent transduction between superconducting and photonic circuits based on the triple-resonance electro-optic principle, with integrated devices incorporating both superconducting and optical cavities on the same chip. Electromagnetically induced transparency is observed, indicating the coherent interaction between microwave and optical photons. Internal conversion efficiency of 25.9 ± 0.3% has been achieved, with 2.05 ± 0.04% total efficiency. Superconducting cavity electro-optics offers broad transduction bandwidth and high scalability and represents a significant step toward integrated hybrid quantum circuits and distributed quantum computation.

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