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1.
Angew Chem Int Ed Engl ; 63(25): e202405173, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38622784

RESUMEN

Constructing amorphous/intermetallic (A/IMC) heterophase structures by breaking the highly ordered IMC phase with disordered amorphous phase is an effective way to improve the electrocatalytic performance of noble metal-based IMC electrocatalysts because of the optimized electronic structure and abundant heterophase boundaries as active sites. In this study, we report the synthesis of ultrathin A/IMC PtPbBi nanosheets (NSs) for boosting hydrogen evolution reaction (HER) and alcohol oxidation reactions. The resulting A/IMC PtPbBi NSs exhibit a remarkably low overpotential of only 25 mV at 10 mA cm-2 for the HER in an acidic electrolyte, together with outstanding stability for 100 h. In addition, the PtPbBi NSs show high mass activities for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR), which are 13.2 and 14.5 times higher than those of commercial Pt/C, respectively. Density functional theory calculations demonstrate that the synergistic effect of amorphous/intermetallic components and multimetallic composition facilitate the electron transfer from the catalyst to key intermediates, thus improving the catalytic activity of MOR. This work establishes a novel pathway for the synthesis of heterophase two-dimensional nanomaterials with high electrocatalytic performance across a wide range of electrochemical applications.

2.
Chem Rec ; 22(10): e202200123, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35758546

RESUMEN

Two-dimensional (2D) nanostructure is currently the subject in the fields of new energy storage and devices. During the past years, a broad range of 2D materials represented by graphene have been developed and endow with excellent electrochemical properties. Among them, elemental 2D materials (Xenes) are an emerged material family for Li/Na-ion battery (LIB/SIB) anodes. Compared with other 2D materials and bulk materials, Xenes may exhibit some great superiorities for Li/Na storage, including excellent conductivity, fast ion diffusion and large active sites exposure. In this review, we provide a systematic summary of the recent progress and achievements of Xenes as well as their applications in LIBs/SIBs. The broad categorization of Xenes from group IIIA to VIA has been concisely outlined, and the related details in syntheses, structures and Li/Na-ion storage properties are reviewed. Further, the latest research progress of Xenes in Li/Na ion batteries are summarized, together with mechanism discussions. Finally, the challenges and prospects of Xenes applied to Li/Na ion battery are proposed based on its current developments.

3.
Future Oncol ; 18(12): 1485-1497, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35114807

RESUMEN

Aim: To explore the relationship between mutations in cfDNA and response to afatinib. Patients & methods: In total, 64 patients from one Chinese site with locally advanced/metastatic EGFRm+ non-small-cell lung cancer, who received afatinib 40 mg once daily, were included. Results: Overall, 33 (82.5%) patients became EGFRm- by visit 3; median progression-free survival was longer in these patients vs those who did not (11.0 vs 5.5 months). Progression-free survival was shorter in 42 (45.2%) patients with non-EGFR co-mutations at baseline vs those without (8.1 vs 12.5 months). Neither difference was significant. Conclusion: Afatinib provided clinical benefit for patients with EGFRm+ non-small-cell lung cancer across all subgroups. EGFRm status assessment in plasma cfDNA is a useful method of monitoring treatment.


We conducted a study in 64 Chinese patients with non-small-cell lung cancer to investigate the relationship between cancer mutations detected in the blood and the response to treatment with afatinib, which is known to be effective against EGFR mutations. Technology is now available to detect these mutations in the blood, as an alternative to obtaining and testing lung tissue samples. All 64 patients had EGFR mutations (and some patients had additional types of mutations) when afatinib was started (visit 1 in the study). By visit 3, most patients (82.5%) no longer had EGFR mutations detected in their blood, and these patients responded better to afatinib than those who still had EGFR mutations in their blood. Patients with additional types of mutations generally did not respond as well as those who had only EGFR mutations. Although results showed clinical benefit with afatinib using assessment of mutation status in the blood, statistical significance could not be shown due to the small size of the study. Clinical Trial Registration: NCT01953913 (ClinicalTrials.gov).


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Afatinib/uso terapéutico , Biomarcadores , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico
4.
J Acoust Soc Am ; 151(4): 2290, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35461493

RESUMEN

In recent years, micro-acoustic devices, such as surface acoustic wave (SAW) devices, and bulk acoustic wave (BAW) devices have been widely used in the areas of Internet of Things and mobile communication. With the increasing demand of information transmission speed, working frequencies of micro-acoustic devices are becoming much higher. To meet the emerging demand, Lamb wave devices with characteristics that are fit for high working frequency come into being. However, Lamb wave devices have more complicated vibrating modes than SAW and BAW devices. Methods used for SAW and BAW devices are no longer suitable for the mode extraction of Lamb wave devices. To solve this difficulty, this paper proposed a method based on machine learning with convolutional neural network to achieve automatic identification. The great ability to handle large amount of images makes it a good option for vibrating mode recognition and extraction. With a pre-trained model, we are able to identify and extract the first two anti-symmetric and symmetric modes of Lamb waves in varisized plate structures. After the successful use of this method in Lamb wave modes automatic extraction, it can be extended to all micro-acoustic devices and all other wave types. The proposed method will further promote the application of the Lamb wave devices.

5.
Opt Express ; 29(21): 33467-33480, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34809158

RESUMEN

Phase-measuring phase-sensitive optical time-domain reflectometry (OTDR) has been widely used for the distributed acoustic sensing. However, the demodulated phase signals are generally noisy due to the laser frequency drift, laser phase noise, and interference fading. These issues are usually addressed individually. In this paper, we propose to address them simultaneously using supervised learning. We first use numerical simulations to generate the corresponding noisy differential phase signals for the given acoustic signals. Then we use the generated acoustic signals and noises together with some real noise data to train an end-to-end convolutional neutral network (CNN) for the acoustic signal enhancement. Three experiments are conduct to evaluate the performance of the proposed signal enhancement method. After enhancement, the average signal-to-noise ratio (SNR) of the recovered PZT vibration signals is improved from 13.4 dB to 42.8 dB, while the average scale-invariant signal-to-distortion ratio (SI-SDR) of the recovered speech signals is improved by 7.7 dB. The results show that, the proposed method can well suppress the noise and signal distortion caused by the laser frequency drift, laser phase noise, and interference fading, while recover the acoustic signals with high fidelity.

6.
Proc Natl Acad Sci U S A ; 115(17): E3978-E3986, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29632194

RESUMEN

Lung cancer is the leading cause of cancer-related death worldwide. Inactivation of tumor suppressor genes (TSGs) promotes lung cancer malignant progression. Here, we take advantage of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated somatic gene knockout in a KrasG12D/+ mouse model to identify bona fide TSGs. From individual knockout of 55 potential TSGs, we identify five genes, including Utx, Ptip, Acp5, Acacb, and Clu, whose knockout significantly promotes lung tumorigenesis. These candidate genes are frequently down-regulated in human lung cancer specimens and significantly associated with survival in patients with lung cancer. Through crossing the conditional Utx knockout allele to the KrasG12D/+ mouse model, we further find that Utx deletion dramatically promotes lung cancer progression. The tumor-promotive effect of Utx knockout in vivo is mainly mediated through an increase of the EZH2 level, which up-regulates the H3K27me3 level. Moreover, the Utx-knockout lung tumors are preferentially sensitive to EZH2 inhibitor treatment. Collectively, our study provides a systematic screening of TSGs in vivo and identifies UTX as an important epigenetic regulator in lung tumorigenesis.


Asunto(s)
Sistemas CRISPR-Cas , Transformación Celular Neoplásica/metabolismo , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Histona Demetilasas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Experimentales/metabolismo , Animales , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Histona Demetilasas/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Ratones Noqueados , Neoplasias Experimentales/genética , Neoplasias Experimentales/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
7.
Future Oncol ; 16(4): 49-60, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31922425

RESUMEN

Aim: Acquired resistance to EGFR tyrosine kinase inhibitors is inevitable in non-small-cell lung cancer. To inform subsequent treatment decisions, we retrospectively assessed therapies following afatinib in Japanese patients from LUX-Lung 3. Patients & methods: LUX-Lung 3 was a randomized, open-label, Phase III study of afatinib versus cisplatin/pemetrexed in treatment-naive patients with EGFR mutation-positive (EGFRm+) advanced lung adenocarcinoma. Results: Among 47 Japanese patients who discontinued first-line afatinib, 91/81/62% received ≥one/two/three subsequent therapies. The most common second-line therapies were platinum-based chemotherapy (38%) and a first-generation EGFR tyrosine kinase inhibitor (17%). Median overall survival (afatinib vs cisplatin/pemetrexed) was 47.8 versus 35.0 months (not significant). Conclusion: First-line afatinib does not appear to diminish suitability for subsequent therapies in EGFRm+ non-small-cell lung cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Inhibidores de Proteínas Quinasas/uso terapéutico , Afatinib/administración & dosificación , Afatinib/efectos adversos , Afatinib/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Manejo de la Enfermedad , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Japón , Estimación de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidad , Mutación , Terapia Neoadyuvante , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
9.
Toxicol Mech Methods ; 25(8): 645-52, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26108275

RESUMEN

Aristolochic acid I (AAI) affects TGF-ß1/Smad signaling, which causes AA nephropathy (AAN), but the mechanisms are not fully understood. We aimed to clarify whether Arkadia and UCH37 participate in TGF-ß1/Smad signaling via Smad7, and the regulatory mechanisms of Smad7. One side, mice and cultured mouse renal tubular epithelial cells (RTECs) were treated with various AAI doses and concentrations, respectively; on the other side, RTECs were transfected with small interfering RNA (siRNA) expression vectors against Arkadia and UCH37 and then treated with 10 µg/ml AAI. And then detect the mRNA and protein levels of Smad7, UCH37, Arkadia and any other relative factors by RT-PCR and Western blotting. In kidney tissues and RTECs, the mRNA and protein levels of Smad7 decreased with increasing AAI doses concentrations by real-time PCR and Western blotting, whereas those of Arkadia, UCH37, Smad2, Smad3 and TßRI increased. Cells transfected with the Arkadia siRNA expression vector showed reduced mRNA and protein levels of vimentin, α-SMA, Smad2, Smad3 and TßRI after AAI treatment, while those of CK18 and Smad7 increased compared with those of untransfected RTECs. Conversely, cells transfected with the UCH37 siRNA expression vector showed the opposite effect on analyzed signaling molecules after AAI treatment. Arkadia and UCH37 participate in TGF-ß1/Smad signaling-mediated renal fibrosis, and Smad7 blocks TGF-ß1 signaling by inhibiting Smad2/Smad3 phosphorylation and enhancing the degradation of TßRI.


Asunto(s)
Ácidos Aristolóquicos/toxicidad , Carcinógenos/toxicidad , Túbulos Renales/efectos de los fármacos , Proteína smad7/antagonistas & inhibidores , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/efectos de los fármacos , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Túbulos Renales/citología , Túbulos Renales/inmunología , Túbulos Renales/metabolismo , Ratones , Nefritis/inducido químicamente , Nefritis/inmunología , Nefritis/metabolismo , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN , ARN Mensajero/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/agonistas , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína smad7/genética , Proteína smad7/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Ubiquitina Tiolesterasa/química , Ubiquitina Tiolesterasa/genética , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/genética
10.
Toxicol Mech Methods ; 24(6): 377-84, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24796935

RESUMEN

Aristolochic acid nephropathy (AAN) is mainly caused by aristolochic acid I (AAI), but the actual mechanism is still uncertain. The current study explored the correlation among the expression of Smad7, p300, histone deacetylase-1 (HDAC1) and the development of AAN using transmission electron microscopy (TEM), RT-PCR, and western blotting in the AAN mouse model and in the AAN cell model. TEM revealed that the renal tubular epithelial cells from the AAI-treated mice presented organelle damages and nuclear deformation. We found that a certain dose of AAI caused renal fibrosis and induced renal tubular epithelial cells to differentiate into myofibroblasts. There was a gradual increase in the expression of HDAC1 mRNA and protein observed using RT-PCR and western blotting in the AAN cell model compared with the control group. Gradual decrease in the expression of Smad7 and p300 mRNA and protein was revealed in the AAN mouse and cell models compared with the control group. These results suggest that AAI dose dependently contributed to the development of AAN, and HDAC1 and p300 participate in the modulation of TGF-ß/Smad pathway-mediated renal interstitial fibrosis.


Asunto(s)
Ácidos Aristolóquicos/toxicidad , Proteína p300 Asociada a E1A/metabolismo , Histona Desacetilasa 1/metabolismo , Enfermedades Renales/inducido químicamente , Actinas/genética , Actinas/metabolismo , Animales , Ácidos Aristolóquicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Proteína p300 Asociada a E1A/genética , Regulación de la Expresión Génica/efectos de los fármacos , Histona Desacetilasa 1/genética , Riñón/efectos de los fármacos , Riñón/ultraestructura , Enfermedades Renales/patología , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo , Organismos Libres de Patógenos Específicos , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
11.
J Colloid Interface Sci ; 670: 311-322, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38763027

RESUMEN

The green synthesis strategy for cellulose-containing hydrogel electrolytes is significant for effectively managing resources, energy, and environmental concerns in the contemporary world. Herein, we propose an all-green strategy using AlCl3/ZnCl2/H2O solvent to create cellulose/polyacrylamide-based hydrogel (AZ-Cel/PAM) with expanded hierarchical topologies. The aqueous AlCl3/ZnCl2 facilitates the efficient dissolution of cellulose at room temperature, and the dispersed Al3+-Zn2+ ions autocatalytic system catalyzes in-situ polymerization of acrylamide (AM) monomer. This expands the AM network within the cellulose framework, forming multiple bonding interactions and stable ion channels. The resulting hybrid hydrogel exhibits improved mechanical properties (tensile strength of 56.54 kPa and compressive strength of 359.43 kPa) and enhanced ionic conductivity (1.99 S/m). Furthermore, it also demonstrates excellent adhesion, freeze resistance (-45 °C), and water retention capabilities. Quantum simulations further clarify the mechanical composition and ion transport mechanism of AZ-Cel/PAM hydrogels. The assembled supercapacitor with the hydrogel electrolyte, demonstrates an ideal area-specific capacitance of 203.80 mF/cm2. This all-green strategy presents a novel approach to developing sustainable energy storage devices.

12.
Transl Oncol ; 45: 101978, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38701650

RESUMEN

OBJECTIVE: This study aimed to investigate TCF19's role in lung cancer development, specifically its involvement in the RAF/MEK/ERK signaling pathway. METHODS: Lung cancer tissue analysis revealed significant TCF19 overexpression. In vitro experiments using A549 and Hop62 cells with TCF19 overexpression demonstrated enhanced cell growth. Transgenic mouse models confirmed TCF19's role in primary tumor development. Transcriptome sequencing identified altered gene expression profiles, linking TCF19 to RAF/MEK/ERK pathway activation. Functional assays elucidated underlying mechanisms, revealing increased phosphorylation of Raf1, MEK1/2, and ERK1/2. Inhibiting RAF1 or ERK through shRaf1 or ERK inhibitor reduced cell cycle-related proteins and inhibited TCF19-overexpressing cell growth. RESULTS: TCF19 was identified as an oncogene in lung carcinoma, specifically impacting the RAF/MEK/ERK pathway. Elevated TCF19 levels in lung cancer suggest targeting TCF19 or its associated pathways as a promising strategy for disease management. CONCLUSION: This study unveils TCF19's oncogenic role in lung cancer, emphasizing its modulation of the RAF/MEK/ERK pathway and presenting a potential therapeutic target for TCF19-overexpressing lung cancers.

13.
J Dermatol ; 50(12): 1531-1538, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37721393

RESUMEN

Of those patients diagnosed with generalized pustular psoriasis (GPP) in Japan, approximately 30% have a prior psoriasis vulgaris (PsV) diagnosis. Therefore, understanding factors associated with a GPP diagnosis is essential for early diagnosis of GPP in patients with PsV. This retrospective cohort study was conducted to identify associated factors for GPP diagnosis in patients with PsV. Eligible patients with two confirmed diagnoses of PsV with/without a confirmed GPP diagnosis (International Classification of Disease 10th revision codes L40.0 and L40.1, respectively) were identified from the Japanese Medical Data Center database (JMDC) (July 1, 2005-January 31, 2019). Weighted logistic regression was used to identify associated factors (based on recorded comorbidities) between the PsV only and PsV with GPP cohorts. Odds ratios (ORs) of ≥1.5, associated with a high probability of a GPP diagnosis, were reported for factors with ≥5 patients/cohort. The time from event to GPP diagnosis was evaluated. The highest associated factor for GPP diagnosis was psoriatic arthritis (OR 20.2, 95% confidence interval [CI] 17.06-23.92, P < 0.0001), which also had the shortest time from event to GPP diagnosis (median 119 days). Other comorbidities associated with GPP diagnosis were other psoriasis, tonsillitis, and sinusitis. Treatments associated with GPP diagnosis included systemic corticosteroids (OR 2.19, 95% CI 1.98-2.43, P < 0.0001; median time from treatment initiation to GPP diagnosis 180 days). Other associated treatments (other immunosuppressants, interleukin [IL]-17 or IL-23 inhibitors, and phototherapy) had a delay of ≥1 year from treatment initiation to GPP diagnosis. Back pain, headache, and fever were also identified as associated with a GPP diagnosis. Patients with PsV requiring systemic therapies are more likely to receive a GPP diagnosis than those not requiring systemic treatment. These data will help identify patients with PsV at high risk of developing GPP and potentially support early GPP diagnosis.


Asunto(s)
Artritis Psoriásica , Psoriasis , Humanos , Estudios Retrospectivos , Japón/epidemiología , Psoriasis/diagnóstico , Psoriasis/epidemiología , Artritis Psoriásica/diagnóstico , Artritis Psoriásica/tratamiento farmacológico , Artritis Psoriásica/epidemiología , Inmunosupresores , Enfermedad Aguda
14.
Int J Biol Macromol ; 253(Pt 1): 126550, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37657569

RESUMEN

From the perspective of environmental sustainability, introducing cellulose into ionic conductive hydrogel is an inevitable trend for the development of flexible conductive materials. We report a double-network cellulose/polyacrylic acid (Cel/PAA) composite hydrogel based on the dissolving of cellulose by AlCl3/ZnCl2 aqueous system. The Cel/PAA composite hydrogel consists of rigid cellulose chains and flexible polyacrylic acid, which synergistically realize the improvement of the mechanical properties. The AlCl3/ZnCl2 aqueous system not only serves as the green solvent for cellulose, but also the Al3+ and Zn2+ metal ions can be served as a catalyst to activate the initiator for polymerization of acrylic acid. Compared with pure cellulose hydrogel, the compression strain of the Cel/PAA composite hydrogel was significantly improved to 80 %, and its conductivity increased by 28.1 %. In addition, its compression stress was enhanced over 2 times than pure PAA hydrogel. The Cel/PAA composite hydrogel exhibits excellent anti-freezing (-45 °C), weight retention (90 %), and conductivity (2.70 S/m) properties, still maintaining transparency and storage stability in the extreme environment. This work presents a facile strategy to develop an ionic conductive cellulose-based composite hydrogel with good conductivity and mechanical properties, which shows potential for the application fields of flexible sensors and 3D-printing functional materials.


Asunto(s)
Celulosa , Hidrogeles , Solventes , Conductividad Eléctrica , Iones
15.
Ultrasonics ; 133: 107038, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37196574

RESUMEN

The fast reduction of the physical size of film bulk acoustic wave resonators as a layered structure implies the intensification of the electric field which can induce large deformation in the functioning state of devices as a circuit element. Consequently, the nonlinear behavior of the resonator and accompanying properties are to be included and evaluated in the development and optimization for performance improvement. With this objective, the nonlinear formulation of a multilayered film bulk acoustic resonator is presented for the analysis of vibration frequencies and mode shapes with the consideration of larger mechanical deformation. The dominantly linear relationship between the voltage or deformation and frequency is obtained to understand the nonlinear behavior and properties which have been subjected to extensive research analytically and experimentally to satisfy the application needs in all modes of communications and network technology.

16.
Micromachines (Basel) ; 14(12)2023 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-38138374

RESUMEN

This paper presents an advanced method that combines coupling-of-modes (COM) theory and the finite element method (FEM), which enables the quick extraction of COM parameters and the accurate prediction of the electroacoustic and temperature behavior of surface acoustic wave (SAW) devices. For validation, firstly, the proposed method is performed for a normal SAW resonator. Then, the validated method is applied to analysis of an I.H.P. SAW resonator based on a 29°YX-LT/SiO2/SiC structure. Via optimization, the electromechanical coupling coefficient (K2) is increased up to 13.92% and a high quality (Q) value of 1265 is obtained; meanwhile, the corresponding temperature coefficient of frequency (TCF) is -10.67 ppm/°C. Furthermore, a double-mode SAW (DMS) filter with low insertion loss and excellent temperature stability is also produced. It is demonstrated that the proposed method is effective even for SAW devices with complex structures, providing a useful tool for the design of SAW devices with improved performance.

17.
Chem Commun (Camb) ; 59(20): 2931-2934, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36799233

RESUMEN

The innovation of NO2 gas sensors is highly desirable in environmental monitoring and human safety. Herein, a macroporous SnO2/MoS2 inverse opal hierarchitecture has been constructed with substantial interface charge transfer, which realizes the efficient and stable detection of NO2 with an enhanced response, fast kinetics, and high selectivity at low temperatures.

18.
Adv Mater ; 34(37): e2203615, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35900215

RESUMEN

Hydrogen spillover (HSo) has emerged to upgrade the hydrogen evolution reaction (HER) activity of Pt-support electrocatalysts, but it is not applicable to the deprotonated oxygen evolution reaction (OER). Non-precious catalysts that can perform well in both HSo and deprotonation (DeP) are extremely desirable for a sustainable hydrogen economy. Herein, an affordable MoS2 /NiPS3 vertical heterostructure catalyst is presented to synergize HSo and DeP for efficient water electrolysis. The internal polarization field (IPF) is clarified as the driving force of HSo in HER electrocatalysis. The HSo from the MoS2 edge to NiPS3 can activate the NiPS3 basal plane to boost the HER activity of the MoS2 /NiPS3 heterostructure (112 mV vs reversible hydrogen electrode (RHE) at 10 mA cm-2 ), while for OER, the IPF in the heterostructure can facilitate the hydroxyl diffusion and render MoS2 -to-NiPS3 /P-to-S dual-pathways for DeP. As a result, the stacking of OER-inactive MoS2 on the NiPS3 surface still brings intriguing OER enhancements. With them serving as electrode couples, the overall water splitting is attested stably with a cell voltage of 1.64 V at 10 mA cm-2 . This research puts forward the IPF as the criterion in the rational design of HSo/DeP-unified non-precious catalysts for efficient water electrolysis.

19.
Artículo en Inglés | MEDLINE | ID: mdl-35239479

RESUMEN

Solving the phase ambiguity problem is crucial to achieving a wide-range and high-precision measurement for the frequency-domain sampling (FDS)-based surface acoustic wave (SAW) delay-line sensor systems. This study proposes an improved phase estimation algorithm called dual-band phase estimation (DBPE) to solve the problem. By using DBPE, the SAW sensor system can obtain an extensive and alterable measuring range without further requirements for sensor design or transmitted signals. Thus, it can be widely used in various FDS-based SAW delay-line sensor systems. Monte Carlo simulations and temperature measuring experiments, based on a YZ-cut LiNbO3 SAW delay-line sensor and a switched frequency-stepped continuous wave (S-FSCW) reader, are performed to demonstrate the algorithm's validity. The Monte Carlo simulations show that DBPE can effectively solve the phase ambiguity problem and has better performance than frequency estimation in measuring precision at a low signal-to-noise ratio (SNR). The temperature-sensing experiments show that DBPE has a good performance in measuring range and precision, serving as a phase ambiguity solver in the temperature sensor system.


Asunto(s)
Algoritmos , Sonido
20.
Environ Sci Pollut Res Int ; 29(23): 34861-34873, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35041166

RESUMEN

The design of highly efficient photoca talysts for clean energy production and environmental remediation are the grand challenges of scientific research. Herein, TiO2@MIL53Fe and CeO2@MIL53Fe composite photocatalysts are synthesized via solvothermal technique. The SEM and TEM micrographs reveal that TiO2 and CeO2 nanoparticles are vertically grown onto the surface of MIL53Fe MOF. Further, HRTEM micrograph confirmed the formation of heterojunction. It has been investigated that the resultant TiO2@MIL53Fe and CeO2@MIL53Fe photocatalysts exhibit remarkably improved visible light activities for H2 production and 2,4-dichlorophenol (2,4-DCP) degradation in comparison to the bare MIL53Fe photocatalyst. The enhanced photoactivities of the fabricated TiO2@MIL53Fe and CeO2@MIL53Fe photocatalysts are attributed to significantly promoted charge separation as confirmed via the surface photo voltage (SPV) and photoluminescence (PL) results. Further, the photocatalysts exhibit high stability and reusability as confirmed via the recyclable tests. This work will promote the design of MOF-based efficient photocatalysts for clean energy production and environment purification.

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