Publications by authors named "Pham Thanh Huy"

Near-ultraviolet (NUV)-pumped white light-emitting-diodes (WLEDs) often suffer from poor color rendering in the 480-520 nm range, highlighting the need for an efficient cyan phosphor with strong absorption at 370-420 nm. This study presents the successful synthesis of cyan-emitting ZnS/ZnO phosphors using a high-energy planetary ball milling method followed by post-annealing. The fabricated phosphors, with particle sizes ranging from 1 to 3 μm, exhibit strong cyan emission with CIE chromaticity coordinates of (0.

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Purposes: The objective of this research was to interpret and analyze the imaging, audiological features and cochlear implantation outcomes in cochlear nerve deficiency children.

Material And Methods: Retrospective analysis.

Results: 25 prelingual hearing loss children diagnosed cochlear nerve deficiency (CND), the age range from 1 to 15 (mean age, 5.

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Recently, deep-red-emitting phosphors that can be excited by ultraviolet (UV) and near-ultraviolet (NUV) light have been extensively investigated for plant growth LED applications. However, due to the harmful effects of these high-energy rays on plants, violet- or blue-excited deep-red-emitting phosphors are considered a more appropriate solution. In this work, SrAlO:Cr phosphors were synthesized using a simple solid-state reaction, revealing a strikingly sharp deep-red emission band centered at 694 nm and effective excitation by violet light.

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Eu-doped phosphors have been much attractive owing to their narrow-band red emission peak at 610-630 nm with high color purity; however, the weak and narrow absorption band in the NUV region limits their applications. Doping a higher amount of Eu ions into a non-concentration quenching host could be key to enhancing the efficiency of the absorption value and emission intensity. Hence, the design of Eu-heavily doped phosphors with a suitable host lattice is key for applications.

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Phosphor-converted white light-emitting diodes (WLEDs) have received significant attention; however, the leaked light from their blue InGaN chips has an undesirable effect on human health. Hence, it is necessary to develop red, green, and blue-emitting phosphors, which can be excited by an NUV chip instead of a blue chip. Herein, green-emitting ZnO:Cu phosphors have been successfully synthesized by a simple and facile thermal diffusion method.

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Although it has been extensively studied for decades, the α-AlO:Cr phosphor has rarely been investigated for horticultural lighting. In this work, for the first time, a prototype of a plant growth light-emitting diode (LED) has been fabricated by coating a deep-red-emitting α-AlO:Cr phosphor onto a near-ultraviolet (NUV) chip. The α-AlO:Cr phosphor, synthesized by a co-precipitation method and annealed at 1500 °C for 2 h, emits an outstanding narrow peak at 695 nm.

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Two-dimensional (2D) van der Waals ferromagnetic materials are emerging as promising candidates for applications in ultra-compact spintronic nanodevices, nanosensors, and information storage. Our recent discovery of the strong room temperature ferromagnetism in single layers of VSe grown on graphite or MoS substrate has opened new opportunities to explore these ultrathin magnets for such applications. In this paper, we present a new type of magnetic sensor that utilizes the single layer VSe film as a highly sensitive magnetic core.

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This paper reports on the in situ observation of phase transformation in an iron carbide nanocrystal encapsulated in a graphitic shell by means of high resolution transmission electron microscopy (HR-TEM). A FeC nanocrystal in orthorhombic (o-FeC) structure with carbon graphitic cover is captured at the initial time of the experiment. Under the projection of a high-energy electron beam (200kV), the graphitic carbon layer evaporates gradually and structural changes in orthorhombic (o-FeC) crystal manifests simultaneously.

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This paper reports a novel way for the synthesis of a europium (Eu)-doped fluor-hydroxyapatite (FHA) nanostructure to control the luminescence of hydroxyapatite nanophosphor, particularly, by applying optimum fluorine concentrations, annealed temperatures and pH value. The Eu-doped FHA was made using the co-precipitation method followed by thermal annealing in air and reducing in a H atmosphere to control the visible light emission center of the nanophosphors. The intensities of the OH group decreased with the increasing fluorine concentrations.

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High-resolution transmission electron microscopy (HRTEM) is used to observe a TiO2/ITO-coated composite nanostructure grown onto single-walled carbon nanotubes (SWCNTs). The SWCNTs, indium tin oxide (ITO), and TiO2 mixtures of anatase (A) and rutile (R) are clearly distinguished in the HRTEM images. The thickness of the SWCNT was about 3 nm, and the TiO2 shell included different polycrystalline structures.

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