Publications by authors named "Duh J"

Multi-walled carbon-nanotube (MWCNT)-decorated WTe nanostars (WTe@CNT nanocomposites) are to be employed for the first time as anode candidates in the development of lithium-ion (Li-ion) batteries. WTe@CNT nanocomposites deliver a high discharge capacity of 1097, 475, 439, 408, 395 and 381 mA h g with an increasing current density of 100, 200, 400, 600, 800 and 1000 mA g, respectively, while WTe nanostars exhibit a reversible capacity of 655, 402, 400, 362, 290 and 197 mA h g with the aforementioned current densities. Furthermore, WTe@CNT nanocomposites exhibit a superior reversible capacity of 592 mA h g at 500 mA g with a capacity retention of 100% achieved over 500 cycles, while bare WTe nanostars deliver ∼85 mA h g over 350 cycles.

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India's experience presents a puzzle at odds with a basic fact of household economics: amidst unprecedented economic growth, average daily calorie consumption has declined in recent decades. Does an improving disease environment explain the calorie decline? A diminished burden of infectious disease could lower energy needs by increasing absorption and effective use of calories. We document a robust effect of disease exposure - measured as infant mortality and as poor sanitation - on calorie consumption.

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This study investigates the formation and removal of PCDD/Fs and dl-PCBs in two woodchips boilers during different operating periods. Results indicate that combustion condition affects PCDD/F and dl-PCB formation within the woodchip combustion process. PCDD/F and dl-PCB concentrations during the start-up period are much higher than those measured during normal operation and shut-down periods due to unstable combustion.

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Catalytic ozonation is progressively becoming an attractive technique for quick water purification but efficient and stable catalysts remains elusive. Here we solvothermally synthesized highly-dispersed CoO nanocrystals over microscale nitrogen-doping graphene (NG) nanosheets and tested it as a synthetic catalyst in the ozonation of phenol in aqueous solutions. Transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectra and X-ray photoelectron spectroscopy were used to determine its morphology, crystallinity, elemental composition and molecular bonds, respectively.

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This study is aimed to explore the effect of fluoride doping and the associated structural transformation on lithium-rich layered cathode materials. The polymeric fluoride source is first adopted for synthesizing lithium intercalated oxide through a newly developed organic precipitation process. A heterostructured spinel/layered composite cathode material is obtained after appreciable fluorination and a superior rate capability is successfully achieved.

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In this study, a jumbo silicon/silicon carbide (Si/SiC) composite (JSC), a novel anode material source, was extracted from solar power industry cutting waste and used as a material for lithium-ion batteries (LIBs), instead of manufacturing the nanolized-Si. Unlike previous methods used for preventing volume expansion and solid electrolyte interphase (SEI), the approach proposed here simply entails applying surface modification to JSC-based electrodes by using nitrogen-atmospheric pressure plasma jet (N-APPJ) treatment process. Surface organic bonds were rearranged and N-doped compounds were formed on the electrodes through applying different plasma treatment durations, and the qualitative examinations of before/after plasma treatment were identified by X-ray photoelectron spectroscopy (XPS) and electron probe microanalyzer (EPMA).

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This study used open-path Fourier transform infrared (OP-FTIR) spectroscopy to continuously assess the variation in chloroform concentrations in the air of an indoor swimming pool. Variables affecting the concentrations of chloroform in air were also monitored. The results showed that chloroform concentrations in air varied significantly during the time of operation of the swimming pool and that there were two peaks in chloroform concentration during the time of operation of the pool.

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Silicon (Si) has been perceived as a promising anode material for lithium-ion batteries for decades due to its superior theoretical capacity, environmental benignity, and earth abundance. To accommodate the drastic volume expansion during lithiation, which is the primary drawback leading to poor cycling life, a novel structural design via fabricating the Marimo-like carbon nanotubes frameworks with silicon nanoparticle (SiNP) filling in internal space has been developed. This facile fabrication procedure involves an in-spaced polymerization process through ex situ polymerization, using pyrrole monomers with a soft organic template in which well-dispersed SiNPs are present.

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RF/microwave soft magnetic films (SMFs) are key materials for miniaturization and multifunctionalization of monolithic microwave integrated circuits (MMICs) and their components, which demand that the SMFs should have higher self-bias ferromagnetic resonance frequency fFMR, and can be fabricated in an IC compatible process. However, self-biased metallic SMFs working at X-band or higher frequency were rarely reported, even though there are urgent demands. In this paper, we report an IC compatible process with two-step superposition to prepare SMFs, where the FeCoB SMFs were deposited on (011) lead zinc niobate-lead titanate substrates using a composition gradient sputtering method.

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Nanocrystalline Co2MnSi Heusler alloy films were deposited on the PZN-PT substrates by a composition gradient sputtering method. It is revealed that this multiferroic heterostructure shows very strong magnetoelectric coupling, leading to continuously tunable microwave frequency characteristics by electric field. With the increase of electric field intensity from 0 to 6 kV/cm, the magnetic anisotropy field H(K) increases from 90 Oe to 182 Oe with an increment of 102%, corresponding to a ME coefficient of 15.

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The fabrication and high-frequency ferromagnetic performances of nanocrystalline Fe70Co30-B soft magnetic films were investigated. It is revealed that the composition gradient sputtering method dramatically improves the high-frequency soft magnetic properties of the as-prepared films. This method gives rise to almost a linearly-increased distribution of compositions and residual stress.

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For swimmers, exposure to chloroform, a probable carcinogen, in indoor swimming pools can be through different pathways such as ingestion, dermal absorption, inhalation during swimming, and inhalation during resting. In order to evaluate health risk results from excessive exposure to chloroform, concentrations of chloroform in pool water were first collected and analyzed. Then, a two-layer model is used, which is capable of estimating the concentrations of chloroform in the boundary layer adjacent to the water surface and the concentrations of chloroform in indoor swimming pool air.

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FeNdBO films were deposited by DC magnetron sputtering. The high-frequency ferromagnetic properties of the films were dramatically enhanced by annealing at 350 degrees C for 1 hour. In comparison with the as-deposited film, the resonance frequency increased from 1.

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With environmental concerns on the toxicity of lead, investigations on lead-free solders become crucial. Studies on lowering process temperature of lead-free solders are required, because the melting points of lead-free solders are higher than original SnPb solders. Melting points of binary solders could be decreased by addition another materials.

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The aim of this study was to evaluate the properties of four heat-pressed glass-ceramic materials after repeated heat-pressing. Two commercially available heat-pressed glass-ceramic systems [Optimal pressable glass-ceramics (OPC and 3G) and Empress pressable glass-ceramics (Empress and Empress2)] were selected. Disc samples (14 mm x 1.

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Global human population and urban development are increasing at unprecedented rates and creating tremendous stress on local, regional, and global air and water quality. However, little is known about how urban areas vary in their capacity to address effectively air and water quality impacts associated to urban development. There exists a need to better understanding the factors that mediate the interactions between urbanisation and variations of environmental quality.

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The aim of this study was to introduce Ag-Cu phase nanopowder as an additive to improve the corrosion behavior of dental amalgams. A novel Ag-Cu nanopowder was synthesized by the precipitation method. An amalgam alloy powder (World-Cap) was added and mixed with 5 wt.

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Objective: To evaluate the cytotoxicity of nickel-based alloy surfaces after nitride film coatings.

Methods: A total of 120 disc-shaped specimens (1.5 x 12.

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The effect of a novel titanium-aluminum nitride film, or (Ti,Al)N film, on the bond strength between a dental porcelain and two nickel-based dental alloy substrates was investigated. A thin layer of (Ti,Al)N film was deposited on flat metal samples using a reactive radio-frequency sputtering method. A uniform thickness of porcelain was applied to the film- coated metal samples.

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In this study, we demonstrate that apoptosis and G2/M cell cycle arrest were easily induced by treatment with the oral-antifungal agent, griseofulvin (GF). The mechanisms of GF-induced G2/M arrest were characterized as (a) induction of abnormal mitotic spindle formation, (b) elevation of cyclin B1/cdc2 kinase activity and (c) down-regulation of myt-1 protein expression. On the other hand, caspase 3 activation, Bcl-2 hyperphosphorylation and inhibition of the normal function of Bcl-2 associated with Bax were demonstrated to be the mechanisms of GF-induced apoptosis.

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In this study, the amount of S-nitrosoglutathione (GSNO) was measured spectrophotometrically at 334 nm. A spontaneous decrease in absorbency at 334 nm was detected when GSNO was exposed to 37 degrees C and a high pH (pH 8.0).

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Purpose: To study the signal transduction mechanisms of tamoxifen via the activation of MAPKs, JNK and ERK in order to understand its regulation of gene expression.

Methods: The effects of tamoxifen (TAM) on the activation of serine/threonine mitogen-activated protein kinase (MAPK, p42/ERK2) and the stress-activated protein kinases (p46 SAPK or c-Jun N-terminal kinase, JNK1) were evaluated using a human cervical epitheloid carcinoma HeLa cell line.

Results: TAM activated both JNK1 and ERK2 activities in a time- and dose-dependent manner in HeLa cells.

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Green tea polyphenols, major constituents of green tea, are potent chemopreventive agents in a number of experimental models of cancer in animals. The mechanisms of cancer protection by these agents are not clear, but may involve modulation of the enzyme systems responsible for the detoxification of chemical carcinogens. The present studies show that a green tea polyphenol extract (GTP) induces chloramphenicol acetyltransferase (CAT) activity in human heptoma HepG2 cells transfected with a plasmid construct which contains an antioxidant-responsive element (ARE) and a minimal glutathione S-transferase Ya promoter linked to the CAT reporter gene.

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