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1.
Nanotechnology ; 33(25)2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35299168

RESUMEN

Stretchable strain sensor, an important paradigm of wearable sensor which can be attached onto clothing or even human skin, is widely used in healthcare, human motion monitoring and human-machine interaction. Pattern-available and facile manufacturing process for strain sensor is pursued all the time. A carbon nanotube (CNT)/silver nanowire (AgNW)-based stretchable strain sensor fabricated by a facile process is reported here. The strain sensor exhibits a considerable Gauge factor of 6.7, long-term durability (>1000 stretching cycles), fast response and recovery (420 ms and 600 ms, respectively), hence the sensor can fulfill the measurement of finger movement. Accordingly, a smart glove comprising a sensor array and a flexible printed circuit board is assembled to detect the bending movement of five fingers simultaneously. Moreover, the glove is wireless and basically fully flexible, it can detect the finger bending of wearer and display the responses distinctly on an APP of a smart phone or a host computer. Our strain senor and smart glove will broaden the materials and applications of wearable sensors.


Asunto(s)
Nanotubos de Carbono , Nanocables , Dispositivos Electrónicos Vestibles , Humanos , Movimiento , Plata
2.
ACS Appl Mater Interfaces ; 12(12): 14136-14144, 2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-32131586

RESUMEN

Flexible pressure sensing is required for the excellent sensing performance and dexterous manipulation of the measured objects in their potential applications. Particularly, the ability to measure and discriminate the direction of force, contact surface, and contact location in real time is crucial for robotics with tactile feedback. Herein, a three-dimensional elastic porous carbon nanotube (CNT) sponge is synthesized by chemical vapor deposition, which is successfully applied in the piezoresistive sensor. In situ scanning electron microscopy study intuitively illustrates the characteristics that the microfibers of the CNT sponge distort and contact with each other under an external force. As a result, new conductive paths are created at the contact points between the CNT microfibers, which provides a basic sensing principle for a piezoresistive sensor. The CNT sponge-based sensor has an ultrahigh sensitivity in a wide pressure range (0-4 kPa for 4015.8 kPa-1), a rapid response time of 120 ms, and excellent durability over 5000 cycles. Moreover, a finlike flexible double-sided electronic skin (e-skin) is fabricated by a simple method to achieve force direction detection, which has potential applications in intelligent wearable devices and human-machine interaction.


Asunto(s)
Técnicas Biosensibles , Torsión Mecánica , Tacto/fisiología , Dispositivos Electrónicos Vestibles , Conductividad Eléctrica , Humanos , Fenómenos Mecánicos , Nanotubos de Carbono/química , Porosidad , Presión , Robótica
3.
J Colloid Interface Sci ; 568: 81-88, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32088454

RESUMEN

Development of high-performance ammonia (NH3) sensor is imperative for monitoring NH3 in the living environment. In this work, to obtain a high performance NH3 gas sensor, structurally well-defined WO3@SnO2 core shell nanosheets with a controllable thickness of SnO2 shell layer have been employed as sensing materials. The prepared core shell nanosheets were used to obtain a miniaturized gas sensor based on micro-electro-mechanical system (MEMS). By tuning the thickness of SnO2 layer via atomic layer deposition, a series of WO3@SnO2 core-shell nanosheets with tunable sensing properties were realized. Particularly, the sensor base on the fabricated WO3@SnO2 nanosheets with 20-nm SnO2 shell layer demonstrated superior gas sensing performance with the highest response (1.55) and selectivity toward 15 ppm NH3 at 200 °C. This remarkable enhancement of NH3 sensing ability could be ascribed to the formation of unique WO3-SnO2 core-shell heterojunction structure. The detailed mechanism was elucidated by the heterojunction-depletion model with the help of specific band alignment.

4.
Microsyst Nanoeng ; 6: 30, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34567644

RESUMEN

Highly sensitive and selective hydrogen sulfide (H2S) sensors based on hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires (NWs) were synthesized via a sequential process combining hard template processing, atomic-layer deposition, and hydrothermal processing. The hierarchical sensing materials were prepared in situ on microelectromechanical systems, which are expected to achieve high-performance gas sensors with superior sensitivity, long-term stability and repeatability, as well as low power consumption. Specifically, the hierarchical nanobowl SnO2@ZnO NW sensor displayed a high sensitivity of 6.24, a fast response and recovery speed (i.e., 14 s and 39 s, respectively), and an excellent selectivity when detecting 1 ppm H2S at 250 °C, whose rate of resistance change (i.e., 5.24) is 2.6 times higher than that of the pristine SnO2 nanobowl sensor. The improved sensing performance could be attributed to the increased specific surface area, the formation of heterojunctions and homojunctions, as well as the additional reaction between ZnO and H2S, which were confirmed by electrochemical characterization and band alignment analysis. Moreover, the well-structured hierarchical sensors maintained stable performance after a month, suggesting excellent stability and repeatability. In summary, such well-designed hierarchical highly ordered nanobowl SnO2@ZnO NW gas sensors demonstrate favorable potential for enhanced sensitive and selective H2S detection with long-term stability and repeatability.

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-743346

RESUMEN

Purpose To investigate the expression and clinical significance of free fatty acid receptor 4 (FFAR4) in hepatocellular carcinoma (HCC) . Methods The expression of FFAR4 in HCC tissues and adjacent tissues of HCC patients was confirmed by 102 cases of liver resection and postoperative pathology, and the relationship between FFAR4 expression and clinical data of HCC patients was analyzed. Quantitative realtime PCR (qRT-PCR) and Western blot were used to detect the expression of FFAR4 in 20 pairs of freshly frozen HCC and adjacent tissues,and the related literatures were reviewed. Results The expression rate of FFAR4 in HCC tissues was 64. 7% (66/102) ,and that in adjacent tissues was 15. 7% (16/102) . The difference in FFAR4 expression between the two groups was statistically significant (P < 0. 05) . The high expression of FFAR4 in HCC tissues was significantly correlated with tumor vascular invasion (P < 0. 05) ,TNM stage (P < 0. 01) ,and Edmondson classification (P < 0. 05) . qRT-PCR and Western blot showed that the expression of FFAR4 in HCC tissues was significantly higher than that in adjacent tissues. The difference between the two groups was statistically significant (P < 0. 01,P< 0. 05) . Conclusion The expression of FFAR4 is significantly associated with the presence of vascular invasion,TNM staging, and Edmondson grading in HCC. High expression of FFAR4 may be closely related to the severity of HCC patients.

6.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-695097

RESUMEN

Purpose To detect the expression of FFAR4 protein and mRNA in pancreatic cancer and to discuss its role and significance in the progression of pancreatic cancer. Meth-ods Immunohistochemistry was used to detect the expression of FFAR4 protein in paraffin-embedded tissues from 62 cases of pathologically confirmed pancreatic cancer. The relationship be-tween the expression of FFAR4 and clinicopathological factors of pancreatic cancer was also studied. At the same time, the ex- pression of FFAR4 in 20 pairs of pancreatic cancer tissues and adjacent tissues were detected using Western bolt and real-time quantitative PCR (qRT-PCR). Results The results of immu-nohistochemistry showed that the expression rate of FFAR4 pro-tein in pancreatic carcinoma was 75. 8% (47/62) significantly higher than that in paratumor tissue 40. 3% (25/62), and the difference was statistically significant (P<0. 05). The high ex-pression of FFAR4 was related to the degree of pancreatic cancer differentiation, TNM stage, and lymph node metastasis ( P <0. 05). Western blot and qRT-PCR showed that the expression of FFAR4 protein and its mRNA expression in pancreatic cancer tissues was significantly higher than matched paracancerous tis-sues. There was a statistically significant difference between the two groups ( P <0. 001 ). Conclusion The dysregulated ex-pression of FFAR4 may be closely related to the progression of pancreatic cancer. It is hopeful that FFAR4 may become a new marker for the prognosis of pancreatic cancer after surgery and a new target for the study of clinical therapeutic drugs.

7.
Opt Express ; 25(10): 10779-10790, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28788767

RESUMEN

Based on photon-phonon nonlinear interaction, a scheme of controllable photon-phonon converters is proposed at single-quantum level in a composed quadratically coupled optomechanical system. With the assistance of the mechanical oscillator, the Kerr nonlinear effect between photon and phonon is enhanced so that the single-photon state can be converted into the phonon state with high fidelity even under the current experimental condition that the single-photon coupling rate is much smaller than mechanical frequency (g ≪ ωm). The state transfer protocols and their transfer fidelity are discussed analytically and numerically. A multi-path photon-phonon converter is designed by combining the optomechanical system with low frequency resonators, which can be controlled by experimentally adjustable parameters. This work provides us a potential platform for quantum state transfer and quantum information.

8.
Chinese Journal of Surgery ; (12): 62-65, 2013.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-247889

RESUMEN

<p><b>OBJECTIVE</b>To identify protein markers for the early diagnosis of pancreatic cancer by a comparative proteomic method.</p><p><b>METHODS</b>Comparative analysis on the pancreatic peripheral blood protein profiling from 20 pancreatic cancer patients, 10 chronic pancreatitis patients and 20 cancer-free controls from May 2007 to September 2008 was carried out by two-dimensional fluorescence electrophoresis (2D-DIGE). Differentially expressed proteins were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The significance difference proteins were confirmed by Western-blot.</p><p><b>RESULTS</b>A differentially expressed proteins: complement 3 (C3) was identified. The gray level of C3 in pancreatic cancer tissue, chronic pancreatitis, and normal control group were 1.63 ± 0.28, 0.65 ± 0.13 (t = 11.81, P = 0.00) and 0.88 ± 0.19 (t = 9.93, P = 0.00), respectively. C3 was high expression in pancreatic cancer group compared with normal control group. The expression of C3 was higher in pancreatic cancer group than in chronic pancreatitis group. The high expression of C3 in pancreatic carcinoma was confirmed by Western blot.</p><p><b>CONCLUSIONS</b>2D-DIGE and MALDI-TOF-MS technology is a quick, easy and practical method to screen for specific biomarkers in serum of patients with pancreatic carcinoma. The identified protein C3 in this study may be as specific serum biomarkers of pancreatic carcinoma.</p>


Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor , Sangre , Estudios de Casos y Controles , Complemento C3 , Diagnóstico Precoz , Neoplasias Pancreáticas , Sangre , Diagnóstico , Pancreatitis Crónica , Sangre , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Electroforesis Bidimensional Diferencial en Gel
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