Improvement in NO2 Gas Sensing Properties of Semiconductor-Type Sensors by Loading Pt into BiVO4 Nanocomposites at Room Temperature.

In the present study, we report the first attempt to prepare a conducive environment for Pt/BiVO4 nanocomposite material reusability for the promotion of sustainable development. Here, the Pt/BiVO4 nanocomposite was prepared using a hydrothermal method with various weight percentages of platinum for use in NO2 gas sensors. The surface morphologies and structure of the Pt/BiVO4 nanocomposite were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The results showed that Pt added to BiVO4 with 3 wt.% Pt/BiVO4 was best at a concentration of 100 ppm NO2, with a response at 167.7, and a response/recovery time of 12/35 s, respectively. The Pt/BiVO4 nanocomposite-based gas sensor exhibits promising nitrogen dioxide gas-sensing characteristics, such as fast response, highly selective detection, and extremely short response/recovery time. Additionally, the mechanisms of gas sensing in Pt/BiVO4 nanocomposites were explored in this paper.

Conductive Polymer (Graphene/PPy)-BiPO4 Composite Applications in Humidity Sensors.

In this particular experiment, a chain of conductive polymer graphene/polypyrrole (Gr/PPy) and BiPO4-or (Gr/PPy)-BiPO4-materials were prepared and used as moisture-sensitive materials. The structure and morphology of the conductive polymer (Gr/PPy)-BiPO4 materials were analyzed using an X-ray diffractometer, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Moreover, properties such as hysteresis loop, impedance, sensing response, and response and recovery time were calculated and evaluated using an inductance-capacitance-resistance analyzer. The data expressed that PPy/BiPO4, as prepared in this study, exhibited excellent sensing properties, with impedance changing by only a few orders of range. Furthermore, the response time and time of recovery were 340 s and 60 s, respectively, and negligible humidity hysteresis occurred at different relative humidities. Therefore, conductive PPy/BiPO4, as prepared in the present study, is an excellent candidate for application in humidity sensors.

Gr/3D-ZnO Nanocomposites as Humidity Sensors with Enhanced Sensing Response.

This work introduces a novel humidity sensor based on a nanocomposite material comprising graphene decorated with three-dimensional flower-like structures of zinc oxide (Gr/3D-ZnO) fabricated via a hydrothermal method with various weight percentages of graphene. The surface structure and morphology of the Gr/3D-ZnO nanocomposite were analyzed using XRD, EDS, SEM, TEM, and Raman spectroscopy. The influence of humidity on the electrical properties of the nanocomposite was also investigated. Experiment results revealed that the nanocomposite with 70 wt% of graphene provided high sensitivity (S = 446) with rapid response times (120 s) and recovery times (160 s). These results demonstrate the excellent potential of the proposed Gr/3D-ZnO nanocomposite in monitoring atmospheric humidity. A discussion on the mechanism underlying the effects of humidity on the Gr/3D-ZnO nanocomposite is also provided.

Evaluation Humidity Sensing Properties of Graphene/HS-TiO2 Nanocomposites.

This paper reports on a nanocomposite synthesized by sol-gel procedure comprising graphene sheets with hollow spheres of titanium dioxide (G/HS-TiO2) with varying weight percentages of graphene for the purpose of humidity sensors. The surface morphology of the nanocomposite was characterized using transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). The structural properties were examined using X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The response to 12-80% RH at room temperature exhibited sensitivity (S = 135). However, the relative humidity range of 12-90% at room temperature exhibited higher sensitivity (S = 557). Sensors fabricated using the proposed nanocomposite exhibited high sensitivity to humidity, high stability, rapid response times, and rapid recovery times with hysteresis error of less than 1.79%. These results demonstrate the outstanding potential of his material for the monitoring of atmospheric humidity. This study also sought to elucidate the mechanisms underlying humidity sensing performance.

Antioxidant and antimicrobial activities of commercial rice wine extracts of Taiwanese Allium fistulosum.

The antioxidant and antibacterial activities of commercial rice wine extracts obtained from different plant parts of Allium fistulosum were assayed. The results showed that commercial rice wine extracts of A. fistulosum contained 28.3-95.9 µL/mL allicin and exhibited significant antioxidant and antibacterial activities. The DPPH radical scavenging capacity ranged from 90.2% to 52.1%, and the IC50 value ranged from 14.6 to 26.0 µg/mL. The total phenolic content of wine extracts was 56.4-198.9 mg GAE/g extracts. The TEAC assay of extracts ranged from 6.2 to 15.5 mmol/g extracts. Antibacterial activities were tested against 4 bacteria b y using agar disc diffusion and tube dilution tests. All extracts exhibited antibacterial activities against gram-positive bacteria, such as Bacillus subtilis and Staphylococcus aureus, and gram-negative bacteria, such as Escherichia coli and Pseudomonas aeruginosa. Thus, A. fistulosum wine extracts could be used as natural and functional additives in cooking foods.

[Design and application of adjustable triangle external fixator for the treatment of calcaneal fractures].

OBJECTIVE: To design a kind of adjustable triangle external fixator, and to use it for treating calcaneal fractures. METHODS: The external fixator was installed into extremity near the both sides of three Kirschner wires crossing the calcaneal tubercle, the lower end of the tibia and the first cuneiform. The support rod length was adjusted to ensure the Kirschner wires affecting the calcaneal tubercle, so the Böhler angle and anteroposterior diameter of the calcaneus were recovered. From April in 2003 to April in 2008, the external fixators were used to treat 34 patients with calcaneal fractures, including 30 males and 4 females, ranging in age from 19 to 54 years, with an average of 36.7 years. The Böhler angles were -5 degree to 15 degree, with an average of 13.5 degrees. According to Sander's classification, 2 patients were type II, 20 patients were type III, and 12 patients were type IV. RESULTS: Thirty-four patients were followed up, and the duration ranged from 3 months to 4 years, averaged 25 months. The Böhler angle recovered to 30 degree to 40 degrees, with a mean of 32.5 degrees. The Maryland mean score improved from preoperative (24.76+/-15.05) to postoperative (83.26+/-16.81). Based on Maryland criteria, 8 patients got an excellent result, 21 good, 3 fair and 2 bad. CONCLUSION: The adjustable triangle external fixator for treating calcaneal fractures has the following advantages : simple approach, good recovery, little reinjury and complications, effectiveness to recovery Böhler angle and anteroposterior diameter of calcaneal, which is an ideal method to treat calcaneal fractures.