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1.
Nanomaterials (Basel) ; 14(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38607109

RESUMEN

Bicontinuous interfacially jammed emulsion gels, also known as Bijels, are a new type of soft condensed matter. Over the last decade, Bijels have attracted considerable attention because of their unique morphology, property, and broad application prospects. In the present review, we summarize the preparation methods and main control strategies of Bijels, focusing on the research progress and application of Bijels as templates for porous materials preparation in recent years. The potential future directions and applications of Bijels are also envisaged.

2.
Opt Express ; 31(22): 37019-37029, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017839

RESUMEN

We have proposed and demonstrated a weak acoustic signal detection technology based on phase-sensitive optical time-domain reflectometry (Φ-OTDR). Non-contact acoustic signals transmitting through air gap between the sound source and the receiver are difficult to detect due to fast attenuation. In order to improve the detection ability of non-contact weak acoustic signals, we demonstrate that multi-mode fiber (MMF) is a better solution than single-mode fiber (SMF) benefiting from its larger core and higher Rayleigh backscattering (RBS) capture coefficient. The frequency signal-to-noise ratio (SNR) has been enhanced by 9.26 dB. Then, with the help of 3D printing technology, elastomers have been designed to further enhance the detection ability due to the high-sensitive response to acoustic signals. Compared with the previous reported "I" type elastomer, the location and frequency SNR enhancement caused by our new proposed "n" type elastomer are 8.39 dB and 11.02 dB in SMF based system. The values are further improved to 10.51 dB and 13.38 dB in MMF and "n" type elastomer integrated system. And a phase-pressure sensitivity of -94.62 dB re rad/µPa has been achieved at 2.5 kHz. This non-contact weak acoustic signal detection technique has great application potential in the quasi-distributed partial discharge (PD) detection of smart grid.

3.
Curr Drug Deliv ; 20(8): 1195-1205, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35570557

RESUMEN

AIM: The aim of this study was to encapsulate glabridin (GB) into nanoparticles, prepared by an ionic-gelation method blended with chitosan (CS) and poly-γ-glutamic acid (γ-PGA) to address the issue of poor stability and low water solubility of glabridin. METHODS: The physicochemical properties of nanoparticles were investigated by transmission electron microscope (TEM), dynamic light scattering (DLS) and fourier-transform infrared (FT-IR) spectroscopy. RESULTS: FT-IR results indicated that the spontaneous interaction between CS, γ-PGA and GB can form a cross linked network-structure, leading to the spontaneous formation of nanoparticles. Morphology of the complex particles was nano-scale spherical shape. Furthermore, particle size was decreased according to the decrease of γ-PGA contents and CS, accompanying with the increase of mixed solution transmittance. The mγ-PGA : mGB = 1: 1 and mCS: (mγ-PGA + mGB) =1: 1 were considered to be a proper preparation condition of CS/γ-PGA/GB hybrid nanoparticles, which produced the smaller nanoparticles with the satisfactory encapsulation efficiency (EE), loading content (LC) and sustained GB release. With the increase of pH values, the potential, EE, and LC decreased gradually, while the particle size increased. The nanoparticles prepared with higher molecular weight γ-PGA had larger particle size and less loading capacity on GB. Additionally, moderate weight ratio of CS/γ-PGA/GB, low pH, and high molecular weight of γ-PGA were favorable for sustained release. CONCLUSION: It can be concluded that the physicochemical properties of nanoparticles and GB release behaviors were affected by several factors including the weight ratio of CS/γ-PGA/GB, pHvalues, and γ-PGA molecular weight (MW). Nanoencapsulation using CS, γ-PGA and GB has a potential application for the development of functional cosmetic products with skin-whitening effect.


Asunto(s)
Quitosano , Nanopartículas , Ácido Glutámico , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas/química , Tamaño de la Partícula
4.
Sensors (Basel) ; 22(5)2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35271143

RESUMEN

This paper proposes a real-time multi-class disturbance detection algorithm based on YOLO for distributed fiber vibration sensing. The algorithm achieves real-time detection of event location and classification on external intrusions sensed by distributed optical fiber sensing system (DOFS) based on phase-sensitive optical time-domain reflectometry (Φ-OTDR). We conducted data collection under perimeter security scenarios and acquired five types of events with a total of 5787 samples. The data is used as a spatial-temporal sensing image in the training of our proposed YOLO-based model (You Only Look Once-based method). Our scheme uses the Darknet53 network to simplify the traditional two-step object detection into a one-step process, using one network structure for both event localization and classification, thus improving the detection speed to achieve real-time operation. Compared with the traditional Fast-RCNN (Fast Region-CNN) and Faster-RCNN (Faster Region-CNN) algorithms, our scheme can achieve 22.83 frames per second (FPS) while maintaining high accuracy (96.14%), which is 44.90 times faster than Fast-RCNN and 3.79 times faster than Faster-RCNN. It achieves real-time operation for locating and classifying intrusion events with continuously recorded sensing data. Experimental results have demonstrated that this scheme provides a solution to real-time, multi-class external intrusion events detection and classification for the Φ-OTDR-based DOFS in practical applications.


Asunto(s)
Algoritmos
5.
Opt Express ; 27(26): 37771-37780, 2019 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-31878552

RESUMEN

Recently, a type of curved light beams, photonic hooks (PHs), was theoretically predicted and experimentally observed. The production of photonic hook (PH) is due to the breaking of structural symmetry of a plane-wave illuminated microparticle. Herein, we presented and implemented a new approach of utilizing the symmetry-broken of the microparticles in material composition for the generation of PHs from Janus microcylinders. Finite element method-based numerical simulation and energy flow-represented theoretical analysis were used to investigate the field distribution characteristics and formation mechanism of the PHs. The full width at half-maximum (FWHM) of the PH (∼0.29λ) is smaller than the FWHM of the photonic nanojet (∼0.35λ) formed from a circular microcylinder with the same geometric radius. By changing the refractive index contrasts between upper and lower half-cylinders or rotating the Janus microcylinder relative to the central axis, the shape profiles of the PHs can be efficiently modulated. The tunability of the PHs through simple stretching or compression operations for the Janus microcylinder constituted by one solid inorganic half-cylinder and the other flexible polymer half-cylinder was studied and discussed as well.

6.
PLoS One ; 9(2): e89793, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24587037

RESUMEN

BACKGROUND: Pay-for-performance for patients is a cost-effective means of improving health behaviours. This study examined the association between the pay time for performance for patients and CHS use by chronic patients. METHODS: A cross-sectional study was undertaken to estimate distribution characteristics of CHS use in 2011 and collect data of socio-demographic characteristics (sex, age, education level, occupation, disposable personal income in 2011, distance between home and community health agency), chronic disease number, and time of pay-for-performance for patients. Participants were 889 rural adults with hypertension or type II diabetes aged 35 and above. Standardized CHS use means chronic patients use CHS at least once per quarter. RESULTS: Patients who received incentives prior to services had 2.724 times greater odds of using standardized CHS than those who received incentives after services (95%CI, 1.986-3.736, P<0.001). For all subgroups (socio-demographic characteristics and chronic disease number), patients who received incentives prior to services were more likely to use standardized CHS than those receiving incentives after services. CONCLUSIONS: Pay time for performance for patients was associated with CHS use by chronic patients. Patients receiving incentive prior to services were more likely to use standardized CHS. And pay time should not be ignored when the policy on pay-for-performance for patients is designed.


Asunto(s)
Servicios de Salud Comunitaria/economía , Reembolso de Incentivo/estadística & datos numéricos , Adulto , Anciano , Análisis Costo-Beneficio , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reembolso de Incentivo/economía
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