71 research outputs found
Enhanced Visible Light Photocatalytic Performance by Nanostructured Semiconductors with Glancing Angle Deposition Method
The glancing angle deposition (GLAD) method in physical vapor deposition is proved to be a versatile tool to fabricate nanostructured TiO2 as the photocatalyst on specific substrates to form self-standing structures, which are much easier to be recycled. And novel designs of doping, decorating photocatalytic active substance, are brought in to make TiO2 respond to visible light. In this chapter, we introduce our previous works such as TiO2 nanorods with CdS quantum dots, noble metallic nanoparticles, coating TiO2 via atomic layer deposition (ALD), and so on
Shape-Controlled Generation of Gold Nanoparticles Assisted by Dual-Molecules: The Development of Hydrogen Peroxide and Oxidase-Based Biosensors
With the assist of dual-molecules, 2-(N-morpholino)ethanesulfonic acid (MES) and sodium citrate, gold nanoparticles (GNPs) with different shapes can be generated in the H2O2-mediated reduction of chloroauric acid. This one-pot reaction can be employed to sensitively detect H2O2, probe substrates or enzymes in oxidase-based reactions as well as prepare branched GNPs controllably. By the “naked eye,” 20 μM H2O2, 0.1 μM glucose, and 0.26 U/mL catalase could be differentiated, respectively. By spectrophotometer, the detected limits of H2O2, glucose, and catalase were 1.0 μM, 0.01 μM, and 0.03 U/mL, respectively, and the detection linear ranges for them were 5.0–400 μM, 0.01–0.3 mM, and 0.03–0.78 U/mL, respectively. The proposed “dual-molecules assist” strategy probably paves a new way for the fabrication of nanosensors based on the growth of anisotropic metal nanoparticles, and the developed catalase sensor can probably be utilized to fabricate ultrasensitive ELISA methods for various analytes
A novel, simple near-infrared thoracoscopic technique by a particular route for locating lung nodules
BackgroundThe localization of pulmonary nodules prior to thoracoscopic surgery remains challenging for thoracic surgeons, especially for those nodules that are not visible or palpable on the lung surface. Our study is a simple and effective minimally invasive method using indocyanine green through a special pathway to locate pulmonary nodules and fluorescence thoracoscopic surgery.MethodsThoracoscopic surgery was performed for 18 undiagnosed peripheral non-solid nodules no larger than 2 cm after location. After 0.3 mg/kg indocyanine green was injected through the peripheral vein, the puncture needle was pulled out after it reached approximately 1 cm of the pulmonary parenchyma near the nodules. This was followed by transfer to the operating room. The nodule was initially localized by using a near-infrared thoracoscope to visualize indocyanine green fluorescence. Then, thoracoscopic resection was performed.ResultsEighteen patients received this special and simple localization method, and underwent near-infrared, image-guided, video-assisted thoracoscopic surgery resection. Median computed tomography (CT) tumor size was 1.2 cm. Median depth from the pleural surface is 1.6 cm (range, 0.1–4.6 cm). The median time of CT-guided intervention was 12 min. The duration of thoracoscopic surgery was 67 min. Indocyanine green fluorescence was clearly identified in 17 of 18 patients (94.4%). The surgical margins were all negative on final pathology. The final diagnoses included 17 primary lung cancers, and 1 benign lung tumor.ConclusionsCT-guided single puncture of indocyanine green after peripheral intravenous injection is a simple, effective, and safe method to locate the nodule. This offers surgeons the ease of localization through direct indocyanine green fluorescence imaging, and it can be used as an effective alternative to other placement methods of locating pulmonary nodules
Sol-gel Synthesis of TiO2 With p-Type Response to Hydrogen Gas at Elevated Temperature
Titanium dioxide is considered as one of the potential candidates for high-temperature gas sensing applications due to its excellent sensitivity and stability. However, its practical use as a gas sensor under elevated conditions is limited on account of its selectivity and insufficient understanding of response conversion from n- to p-type. To this context, the present work is intended to prepare and understand the p-type response of anatase TiO2 toward H2 gas (20–1,000 ppm) at elevated temperature (500°C). Sol-gel route is adopted to facilely synthesize powders containing pure and chromium (1–10 at.%) doped TiO2 nanoparticles, which are then brushed onto substrates with already patterned inter-digitated platinum electrodes. In this work, even, the undoped TiO2 samples showed p-type gas sensing response, which then decreased with Cr doping. However, in comparison to previously reported work, the sensing characteristics of all sensors is improved. For instance, 5 at.% Cr-TiO2 showed high response (147), fast response and recovery (142/123s) time, and good selectivity to hydrogen against monoxide and methane. Despite better response values, the TiO2 based samples show instability and drift in baseline resistance; such issues were not observed for Cr-doped TiO2 samples (≥3 at.%). The powders were further analyzed by XRD, SEM, TEM, and XPS to understand the basic characteristics, p-type response and stability. Further, a plausible sensing mechanism is discussed on basis of results obtained from aforementioned techniques
Phase control and Young’s modulus of tungsten thin film prepared by dual ion beam sputtering deposition
In this letter, tungsten films of varying thickness from ∼20 nm to ∼80 nm were prepared at different deposition temperature by Dual ion beam sputtering deposition (DIBSD) method. The influence of thickness and deposition temperature on the films phase, microstructure and Young’s modulus was studied briefly. The experiments prove that a double-layer structure, formation takes place i.e. β phase tungsten layer (low crystallinity) forms adjacent to the substrate and α tungsten phase layer (high crystallinity) forms above β phase. The increase in both the thickness and deposition temperature promotes the transformation from β phase to α phase which initiates from the interface between two phases. There is a critical thickness of ∼20 nm below which the film is a pure β phase, and the minimum thickness of forming pure α phase is affected by the deposition temperature, with 74 nm at 450°C, and 58 nm at 600°C. Furthermore, the decrease Young’s modulus of the tungsten film is ascribed to the formation of β phase which possesses low crystallinity with low density
A Multiple Sensors Platform Method for Power Line Inspection Based on a Large Unmanned Helicopter
Many theoretical and experimental studies have been carried out in order to improve the efficiency and reduce labor for power line inspection, but problems related to stability, efficiency, and comprehensiveness still exist. This paper presents a multiple sensors platform method for overhead power line inspection based on the use of a large unmanned helicopter. Compared with the existing methods, multiple sensors can realize synchronized inspection on all power line components and surrounding objects within one sortie. Flight safety of unmanned helicopter, scheduling of sensors and exact tracking on power line components are very important aspects when using the proposed multiple sensors platform, therefore this paper introduces in detail the planning method for the flight path of the unmanned helicopter and tasks of the sensors before inspecting power lines, and the method used for tracking power lines and insulators automatically during the inspection process. To validate the method, experiments on a transmission line at Qingyuan in Guangdong Province were carried out, the results show that the proposed method is effective for power line inspection
Shape-Controlled Generation of Gold Nanoparticles Assisted by Dual-Molecules: The Development of Hydrogen Peroxide and Oxidase-Based Biosensors
With the assist of dual-molecules, 2-(N-morpholino)ethanesulfonic acid (MES) and sodium citrate, gold nanoparticles (GNPs) with different shapes can be generated in the H2O2-mediated reduction of chloroauric acid. This one-pot reaction can be employed to sensitively detect H2O2, probe substrates or enzymes in oxidase-based reactions as well as prepare branched GNPs controllably. By the “naked eye,” 20 μM H2O2, 0.1 μM glucose, and 0.26 U/mL catalase could be differentiated, respectively. By spectrophotometer, the detected limits of H2O2, glucose, and catalase were 1.0 μM, 0.01 μM, and 0.03 U/mL, respectively, and the detection linear ranges for them were 5.0–400 μM, 0.01–0.3 mM, and 0.03–0.78 U/mL, respectively. The proposed “dual-molecules assist” strategy probably paves a new way for the fabrication of nanosensors based on the growth of anisotropic metal nanoparticles, and the developed catalase sensor can probably be utilized to fabricate ultrasensitive ELISA methods for various analytes
- …