7,426 research outputs found
How long do the Hong Kong Chinese expect their URTI to last? – Effects on antibiotic use
published_or_final_versio
Ultrasonic extraction of flavonoids and phenolics from loquat (Eriobotrya japonica Lindl.) flowers
Ethanol was used to extract flavonoids and phenolics from loquat (Eriobotrya japonica Lindl. cv. Ruantiaobaisha) flowers with ultrasonic pharmaceutical managing machine. Single-factor and orthogonal experiment were used to investigate the optimum extraction condition. The results showed that, the combination of 30°C, 80 min, 60% ethanol and 1:40 material ratio was optimum extraction condition with the highest yields of flavonoids and phenolics at 47 kHz/500 W. Under the optimum extraction condition, two consecutive extractions was enough, the extraction rates of flavonoids and phenolics were all more than 90%, with the contents of 10.59 and 102.02 mg/g dry weight, respectively.Key words: Eriobotrya japonica, flower, flavonoids, phenolics, ultrasonic extraction
Five-year outcomes of western mental health training for Traditional Chinese Medicine Practitioners
published_or_final_versio
Embedded metal oxide plasmonics using local plasma oxidation of AZO for planar metasurfaces
New methods for achieving high‐quality conducting oxide metasurfaces are of great importance for a range of emerging applications from infrared thermal control coatings to epsilon‐near‐zero nonlinear optics. This work demonstrates the viability of plasma patterning as a technique to selectively and locally modulate the carrier density in planar Al‐doped ZnO (AZO) metasurfaces without any associated topographical surface profile. This technique stands in strong contrast to conventional physical patterning which results in nonplanar textured surfaces. The approach can open up a new route to form novel photonic devices with planar metasurfaces, for example, antireflective coatings and multi‐layer devices. To demonstrate the performance of the carrier‐modulated AZO metasurfaces, two types of devices are realized using the demonstrated plasma patterning. A metasurface optical solar reflector is shown to produce infrared emissivity equivalent to a conventional etched design. Second, a multiband metasurface is achieved by integrating a Au visible‐range metasurface on top of the planar AZO infrared metasurface. Independent control of spectral bands without significant cross‐talk between infrared and visible functionalities is achieved. Local carrier tuning of conducting oxide films offers a conceptually new approach for oxide‐based photonics and nanoelectronics and opens up new routes for integrated planar metasurfaces in optical technology
Novel application of magnetoresistive sensors for high-voltage transmission-line monitoring
High-voltage transmission lines are responsible for transmission of electric power. Their sag and electric current are important parameters for transmission-line monitoring. In this paper, a simple and promising method based on magnetoresistive sensors is proposed for transmission-line monitoring. This is a noncontact method and its installation is simple without the need for power cut. The method involves measuring emanated magnetic field from a line conductor at the ground level and, then, calculating the source position and current inversely. A proof-of-concept laboratory setup was constructed and a series of experiments were carried out for demonstration. This method can handle complicated transmission-line configuration by integrating the stochastic optimization approach into the inverse electromagnetic calculation. It was tested with the computational simulation of a 500 kV transmission-line configuration. The result shows the feasibility of using this transmission-line monitoring method in reality. © 2011 IEEE.published_or_final_versio
The lived experience of 8 Hong Kong nurses during the SAR outbreak
2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Photothermoelectric and photoelectric contributions to light detection in metal-graphene-metal photodetectors.
Graphene's high mobility and Fermi velocity, combined with its constant light absorption in the visible to far-infrared range, make it an ideal material to fabricate high-speed and ultrabroadband photodetectors. However, the precise mechanism of photodetection is still debated. Here, we report wavelength and polarization-dependent measurements of metal-graphene-metal photodetectors. This allows us to quantify and control the relative contributions of both photothermo- and photoelectric effects, both adding to the overall photoresponse. This paves the way for a more efficient photodetector design for ultrafast operating speeds
Public views towards community health and hospital-based outpatient services and their utilisation in Zhejiang, China: a mixed methods study
published_or_final_versio
Laser-induced etching of few-layer graphene synthesized by Rapid-Chemical Vapour Deposition on Cu thin films
The outstanding electrical and mechanical properties of graphene make it very
attractive for several applications, Nanoelectronics above all. However a
reproducible and non destructive way to produce high quality, large-scale area,
single layer graphene sheets is still lacking. Chemical Vapour Deposition of
graphene on Cu catalytic thin films represents a promising method to reach this
goal, because of the low temperatures (T < 900 Celsius degrees) involved during
the process and of the theoretically expected monolayer self-limiting growth.
On the contrary such self-limiting growth is not commonly observed in
experiments, thus making the development of techniques allowing for a better
control of graphene growth highly desirable. Here we report about the local
ablation effect, arising in Raman analysis, due to the heat transfer induced by
the laser incident beam onto the graphene sample.Comment: v1:9 pages, 8 figures, submitted to SpringerPlus; v2: 11 pages,
PDFLaTeX, 9 figures, revised peer-reviewed version resubmitted to
SpringerPlus; 1 figure added, figure 1 and 4 replaced,typos corrected,
"Results and discussion" section significantly extended to better explain
etching mechanism and features of Raman spectra, references adde
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