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Showing papers by "Nanchang University published in 2005"


Journal ArticleDOI
TL;DR: In this paper, seven different chemometric models, such as classical least squares (CLS), principal components regression (PCR), partial least square (PLS), and artificial neural networks (ANN), were applied to resolve the overlapping spectra and to determine these compounds simultaneously.

126 citations


Journal ArticleDOI
TL;DR: Two isomeric phenylethanoid glycosides, acteosides and isoacteoside, were isolated and purified from the seeds of Plantago psyllium L. for the first time by high-speed counter-current chromatography using a solvent system consisting of ethyl acetate-water.

113 citations


Journal ArticleDOI
Chunlan Mo1, Wenqing Fang1, Yong Pu1, Hechu Liu1, Fengyi Jiang1 
TL;DR: In this paper, high performance InGaN blue light-emitting diodes (LEDs) were fabricated by metalorganic chemical vapor deposition on Si(1.1) substrates.

103 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the catalytic activity and coke resistance of La 2 O 3 promoted nickel-based catalysts in a fixed-bed flow reactor and found that BaTiO 3 is an ideal support.
Abstract: The catalytic activity and coke resistance of La 2 O 3 promoted nickel-based catalysts are investigated in a fixed-bed flow reactor. The contents of carbon deposited on catalysts were measured by a carbon combustion method. Catalysts were characterized by CO–TPD, CO 2 –TPD, TPR, XPS and XRD techniques, and the results were correlated with the coke resistance of the catalysts. It is found that the catalytic activity, resistance to carbon deposition and the stability of the catalysts can be greatly improved with the addition of a rare earth oxide. It is found that BaTiO 3 is an ideal support. Thus 5.0 wt.% Ni–0.75 wt.% La–BaTiO 3 catalyst shows great resistance to coke formation and higher thermal stability as well as higher catalytic activity, than the catalysts 5.0 wt.% Ni/La–BaTiO 3 (Ba/La = 1/0.002) and 5.0 wt.% Ni–1.5 wt.% La/BaTiO 3 .

77 citations


Journal ArticleDOI
TL;DR: In this article, an alternative route for the synthesis of ceria nanoparticles by mechanochemical reaction with reactants containing crystalline water was proposed, and it was suggested that the existence of by-product NaCl in as-milled powder could greatly decrease the aggregation of CeO 2 particles during calcination, which benefited the formation of finer crystal ceria.

77 citations


Journal ArticleDOI
15 Mar 2005-Talanta
TL;DR: This study has shown with the use of UV-vis spectrophotometry and the constant wavelength synchronous fluorescence spectroscopy techniques that the pharmaceutical drug, chlorpromazine hydrochloride (CPZ), intercalates into the deoxyribonucleic acid (DNA) double helix by partial exchange with the Neutral Red (NR) molecular probe.

73 citations


Journal ArticleDOI
TL;DR: In this article, a method was developed for the simultaneous determination of four carbamate pesticides, propoxur, isoprocarb, carbaryl and carbofuran, based on their anodic voltammetric behavior observed following their alkaline hydrolysis, which produced electroactive phenol derivatives.

71 citations


Journal ArticleDOI
TL;DR: In this article, a low-temperature ZnO buffer layer was introduced to accommodate the lattice mismatch and thermal expansion coefficient mismatch between the epitaxial layer and the AlN buffer layer.

66 citations


Journal ArticleDOI
Xun-Hua Gong1
TL;DR: In this paper, the set-valued vector optimization problems with constraint in locally convex spaces were considered and the necessary and sufficient conditions for Henig efficient solution pair, globally proper efficient and super efficient solution pairs without ordering cones having the nonempty interior were presented.

64 citations


Journal ArticleDOI
Jiangnan Dai1, Hechu Liu1, Wenqing Fang1, Li Wang1, Yong Pu1, Yufeng Chen1, Fengyi Jiang1 
TL;DR: The epitaxial growth of high-quality ZnO thin films on GaN/c-Al2O3 templates by atmospheric pressure metal organic chemical vapor deposition (MOCVD) using deionized water (H2O) and diethyl zinc (DEZn) as the O and Zn sources, respectively, was presented in this paper.

47 citations


Journal ArticleDOI
TL;DR: In this article, high-quality poly(5-nitroindole) (PNP) films were synthesized electrochemically by the direct anodic oxidation of 5-nitrogen-indole in boron trifluoride diethyl etherate (BFEE) containing additional 10% Diethyl Ether (EE) by volume.
Abstract: High-quality poly(5-nitroindole) (PNP) films were synthesized electrochemically by the direct anodic oxidation of 5-nitroindole in boron trifluoride diethyl etherate (BFEE) containing additional 10% diethyl ether (EE) (by volume). The addition of EE to BFEE could improve the solubility of the monomer. The oxidation potential onset of 5-nitroindole in this medium was measured to be only 1.04 V versus a saturated calomel electrode (SCE), which was much lower than that determined in acetonitrile and 0.1 mol L−1 tetrabutylammonium tetrafluoroborate (1.53 V vs SCE). PNP films obtained from this medium showed good electrochemical behavior and good thermal stability with a conductivity of 10−2 S cm−1; this indicated that BFEE containing 10% EE was a suitable medium for the electrosyntheses of PNP films. Structural studies showed that the polymerization of the 5-nitroindole ring occurred at the 2,3-position. As-formed PNP films were thoroughly soluble in the strong polar organic solvent dimethyl sulfoxide and partly soluble in tetrahydrofuran or acetone. Fluorescent spectral studies indicated that PNP was a good green-light emitter, with excitation and emission wavelengths of 420 and 550 nm, respectively. To the best of our knowledge, this is the first time that nitro-group-substituted high-quality conducting polymer films have been electrodeposited. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3986–3997, 2005

Journal ArticleDOI
TL;DR: In this article, a series of catalysts containing transition metals were prepared by impregnation and precipitation methods, and the results indicated that Cu is a promising catalyst as it eliminated almost totally the chroma of the acid scarlet aqueous solution accompanied with a good chemical oxygen demand (COD) removal rate.
Abstract: This article presented an approach for the treatment of dye wastewater using H 2 O 2 and heterogeneous catalysts. In order to screen out an effective catalyst, a series of catalysts containing transition metals were prepared by impregnation and precipitation methods. The results indicate that Cu is a promising catalyst as it eliminated almost totally the chroma of the acid scarlet aqueous solution accompanied with a good chemical oxygen demand (COD) removal rate. The results also show that the catalysts prepared by precipitation were more effective than those prepared by impregnation. Moreover, the activity decrease of the catalyst was not changed between batches, and the catalysts could be recovered after treatment. The results were also satisfied when the catalyst was used to treat other dye wastewater.

Journal ArticleDOI
TL;DR: In this paper, optical absorption and emission intensity have been investigated for a new erbium-doped lanthanum calcium borate crystal Er 3+ :La 2 CaB 10 O 19 (Er:LCB), and spectral parameters have been estimated from absorption data based on Judd-Ofelt theory.

Journal ArticleDOI
TL;DR: In this paper, the annealing effect on the optical properties of ZnO epilayers was reported, and strong green photoluminescence was observed in the as-grown films while the as grown films showed only near band edge emission.

Journal ArticleDOI
TL;DR: In this paper, five new supramolecular lanthanide coordination polymers with three different structures, La-2(IA)(3)(phen)(2) center dot 2H(2)O(n) (1), {[Ln(IA)1.5)(phen)] center dot xH( 2)O} (n) [X = 1, Ln = Eu (2); x = 0.25, Lln = Dy (3)], and [Ln

Journal ArticleDOI
TL;DR: Yan et al. as mentioned in this paper presented a coupled thermo-mechanical model of plane-strain orthogonal turning of hardened steel, which takes into account the effect of the large strain, strain-rate, temperature and initial workpiece hardness.

Journal ArticleDOI
TL;DR: Based on back scattered electron images and electron micro-probe analysis results, four alteration layers, including a transition layer, a reticulated ferric oxide layer, nubby and cellular layers, were identified in the naturally weathering products of pyrite.
Abstract: Based on back scattered electron images and electron micro-probe analysis results, four alteration layers, including a transition layer, a reticulated ferric oxide layer, a nubby ferric oxide layer and a cellular ferric oxide layer, were identified in the naturally weathering products of pyrite. These layers represent a progressive alteration sequence of pyrite under weathering conditions. The cellular ferric oxide layer correlates with the strongest weathering phase and results from the dissolution of nubby ferric oxide by acidic porewater. Leaching coefficient was introduced to better express the response of element mobility to the degree of pyrite weathering. Its variation shows that the mobility of S, Co and Bi is stronger than As, Cu and Zn. Sulfur in pyrite is oxidized to sulfuric acid and sulfate that are basically released into to porewater, and heavy metals Co and Bi are evidently released by acid dissolution. As, Cu and Zn are enriched in ferric oxide by adsorption and by co-precipitation, but they would re-release to the environment via desorption or dissolution when porewater pH becomes low enough. Consequently, Co, Bi, As, Cu and Zn may pose a substantial impact on water quality. Considering that metal mobility and its concentration in mine waste are two important factors influencing heavy metal pollution at mining-impacted sites, Bi and Co are more important pollutants in this case.

Journal ArticleDOI
TL;DR: In this paper, high quality poly (5-nitroindole) (PNP) films were synthesized electrochemically by direct anodic oxidation of 5-nitron-indole in boron trifluoride diethyl etherate (BFEE) containing additional 10% dietyl ether (by volume).

Journal ArticleDOI
TL;DR: In this article, a double-crystal X-ray diffractometer was used to characterize the structural properties of an Epitaxial ZnO thin film on 2-in diameter Si(1.1) substrates by atmospheric pressure metalorganic chemical vapor deposition.

Journal ArticleDOI
TL;DR: The assay method developed in this paper was found to be simple, reproducible, and reliable and, thus, ideally suitable for the quality control of TGC-derived products and raw materials.
Abstract: Tea glycoprotein (TGC) was purified by Sephadex G-100 gel filtration, and its purity and molecular weight (MW) were determined by high performance gel permeation chromatography. The gel permeation chromatography (GPC) elution behavior of TGC on an Ultrahydrogel 500 (7.8×300 mm) column was studied using a mobile phase with various concentrations of NaCl. A dextran T system was found to be unsuitable as MW calibration standards in GPC because the MW of TGC was changed with the change of ionic concentration in the mobile phase. Thus, the purified TGC obtained in this study was standardized and used instead as the calibration standards for the determination and comparison of TGCs in tea samples collected from different geographic locations and species varieties. The GPC was run at 35°C on an Ultrahydrogel 500 column (7.8×300 mm) with a refractive index detector. Distilled water was used as the mobile phase at a flow rate of 0.6 ml·min−1. The calibration curve was linear over the TGC concentration range of 0.604–6.04 mg·ml−1, with a correlation coefficient of r=0.9997. The TGC mass recovery ranged from 80.4 to 93.2%, with a relative standard deviation of 5.42%. The assay method developed in this paper was found to be simple, reproducible, and reliable and, thus, ideally suitable for the quality control of TGC-derived products and raw materials.

Journal ArticleDOI
Jun-Yi Fu1
TL;DR: The natural quasi-concavity of set-valued mappings in an ordered vector space is introduced and existence theorems for vector equilibrium problems involvingSet-valued monotone mappings are obtained and the convexity of the solution set is shown.
Abstract: The natural quasi-concavity of set-valued mappings in an ordered vector space is introduced. Existence theorems for vector equilibrium problems involving set-valued monotone mappings are obtained and the convexity of the solution set is shown.

Journal ArticleDOI
Li Wang1, Yong Pu1, Wenqing Fang1, Jiangnan Dai1, Yufeng Chen1, Chunlan Mo1, Fengyi Jiang1 
TL;DR: In this article, the effect of buffer layers grown at different temperature on the film quality was studied and it was found that the low-temperature buffer layer was effective to improve the surface morphology, but was not effective in improving the structural quality.

Journal ArticleDOI
TL;DR: In this article, the effects of yttrium on the hydrogenation performance and surface properties of a Ru/sepiolite catalyst were studied, and the results showed that the presence of Yttrium can increase hydrogenation activity and anti-poisoning capacity.
Abstract: The effects of yttrium on the hydrogenation performance and surface properties of a Ru/sepiolite catalyst were studied. With CO2 methanation and CS2 poisoning as the testing reactons, TPR, TPD, XRD and CO chemisorption as the characterizations, the results showed that the presence of yttrium can increase the hydrogenation activity and anti-poisoning capacity of the Ru/sepiolite catalyst, which is due to a change of surface properties of the Ru/sepiolite. In the process of the catalytic reaction, the adjusting behavior of yttrium for the Ru/sepiolite catalyst aids in increasing the catalytic activity and anti-poisoning capacity of the catalyst.

Journal ArticleDOI
TL;DR: The perovskite-like LaSrCoO 4 mixed oxides were prepared by the gelatin, polyglycol gel and polyacrylamide gel methods and were used successfully for CO and C 3 H 8 oxidation.

Journal ArticleDOI
TL;DR: In this article, the nitrogen atom of an atpt ligand coordinates to metal ions in 1/3. And the photophysical properties and thermal stability of 1 were investigated, in which 4,4′-bpy acts as template.

Journal ArticleDOI
TL;DR: In this paper, a controlled grafting of well-defined polymer brushes on the polyvinylidene fluoride (PVDF) films was carried out by the surface-initiated Atom Transfer Radical polymerization (ATRP).
Abstract: Controlled grafting of well-defined polymer brushes on the poly(vinylidene fluoride) (PVDF) films was carried out by the surface-initiated Atom Transfer Radical polymerization (ATRP). Surface-initiators were immobilized on the PVDF films by surface hydroxylation and esterification of the surface-tethered hydroxyl groups with 2-bromoisobutyrate bromide. Water contact angles on PVDF films were reduced by surface grafting of poly(ethylene glycol) monomethacrylate (PEGMA) and methyl methacrylate (MMA). Kinetics study revealed a linear increase in the graft concentration of PMMA and PEGMA with the reaction time, indicating that the chain growth from the surface, was consistence with a "controlled" or "living" process.

Journal ArticleDOI
TL;DR: In this article, the performance of an irreversible regenerative magnetic Brayton refrigeration cycle is investigated with the help of thermodynamic properties of paramagnetic materials based on statistical mechanics, and the minimum ratio and the lower bound of the optimal ratio of two magnetic fields are determined and the optimal criteria of cyclic parameters obtained.
Abstract: With the help of thermodynamic properties of paramagnetic materials based on statistical mechanics, the performance of an irreversible regenerative magnetic Brayton refrigeration cycle is investigated. Expressions of some important parameters such as the coefficient of performance, refrigeration load and work input are derived analytically and are used to reveal the general performance characteristics of the cycle. Moreover, the minimum ratio and the lower bound of the optimal ratio of two magnetic fields are determined and the optimal criteria of the cyclic parameters obtained. Several special cases are discussed in detail. The results obtained will be helpful to deeply understand the performance of an irreversible regenerative magnetic Brayton refrigeration cycle.

Proceedings ArticleDOI
19 Sep 2005
TL;DR: Based on a series of experimental results on Corel colour images, it is found that the KKMeans and KGMM can outperform the traditional KMean and GMM consistently, respectively.
Abstract: We propose two new methods in the nonlinear kernel feature space for pixel clustering based on the traditional KMeans and Gaussian mixture model (GMM). Unlike the previous work on the kernel machines, we give out a new perspective on the new developed kernel machines. That is, kernel principle component analysis (KPCA) combined with the KMeans and the GMM are kernel KMeans (KKMeans) and kernel GMM (KGMM), respectively. In this paper, we prove the new perspective on KKMeans and give out a clear statement on the KGMM as well. Based on this new perspectives, we can implement the KKMeans and the KGMM conveniently. At the end of the paper, we utilize these new algorithms on the problem of the colour image segmentation. Based on a series of experimental results on Corel colour images, we find that the KKMeans and KGMM can outperform the traditional KMeans and GMM consistently, respectively.

Journal ArticleDOI
TL;DR: In this article, the enantiomeric excess is 10-15% higher for the allylation of benzaldehyde when using N,N'-dibenzyl-tartramide auxiliary 5b than when using n,N-diphenyl-toothramide (5a).

Journal ArticleDOI
TL;DR: Mesoporous TiO2-CeO2mixed oxides were synthesized under easy-operating neutral conditions by means of FT-IR, XRD, and N2adsorption methods.
Abstract: Mesoporous TiO2-CeO2mixed oxides (m-TiO2-CeO2) were synthesized under easy-operating neutral conditions. The structure was characterized by means of FT-IR, XRD, and N2adsorption methods. For methanol decomposition to CO and H2, the catalytic activity of the Ru/ m-TiO2-CeO2 catalyst was higher than that of the Ru/ m-TiO2.