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[en] A new and non-toxic probe 1 is synthesized and acted as fluorogenic sensor for Al3+ detection in CH3CH2OH / H2O ( 1: 1, v / v). Besides the specific Al3+ induced a yellow solution of probe 1 to turn to colorless and with a 33 - fold fluorescence enhancement at 440 nm. Probe 1 is highly selective to Al3+ among other tested metal ions and anions with the detection limit is 0.37 μM. What's more, the binding constant between probe 1 and Al3+ is 7.62 × 106 M−1. The mechanism is confirmed by ESI - MS and a stoichiometric ratio of 1: 1 between probe 1 and AI3+. The reversible ‘‘off-on’’ Al3+ response, fine cell permeability and cell imaging ability displays that its potential application in both environmental and Al3+ polluted biological samples.
[en] Si(100) wafers were implanted with Al at 500 C to high doses at multi-energies and were oxidized in 1 atm flowing oxygen at 1000-1200 C. Morphology, structure, and oxidation behavior of the implanted and oxidized Si were studied using optical microscopy, atomic force microscopy, and cross-sectional transmission electron microscopy in conjunction with selected area electron diffraction and energy dispersive x-ray analysis. Large Al precipitates were formed and embedded near the surface region of the implanted Si. Oxidation rate of the Al-implanted Si wafers was lower than that of virgin Si. The unique morphology of the implanted Si results from rpaid Al diffusion and segregation promoted by hot implantation. Reduction of the oxidation rate of Si by Al implantation is attributed to preferential oxidation of Al and formation of a continuous diffusion barrier of Al2O3
[en] The calcium aluminum zincates Ca14(Al1-2xTixZnx)10Zn6O35, in which Al3+ sites in the host material Ca14Al10Zn6O35 are simultaneously substituted by Ti4+ and Zn2+, were synthesized by a polymerized complex method. Al3+ ions could be replaced up to an x value of 0.1. The host material does not exhibit fluorescence, while the cation-substituted samples show an emission band centered at 383 nm under excitation by UV light at 243 nm. The emission intensity increases with x up to 0.1 and then gradually decreases as x is further increased. The emission wavelength also becomes longer with increasing temperature. Based on the properties of other Ti4+-containing fluorescent materials, the emission of Ca14(Al1-2xTixZnx)10Zn6O35 is attributed to charge transfer-type fluorescence resulting from [TiO6] octahedra.
[en] Highlights: • Elastic properties of nanocrystalline Ni-Zn-Al ferrite synthesized by citrate-gel autocombustion method has been presented. • The elastic wave velocity and Debye temperature are increased with increasing Al3+ concentration. • A new antistructural modeling for describing of active surface centers is discussed.
[en] A novel Schiff base ligand (N, O system) 5-methoxy-2-phenyliminomethylphenol (5-CH3O-PMP) was synthesized. Using the synthesized ligand as a fluorescent reagent, a fluorometric method was developed for the quantitative analysis of Al(III) ion. The quantitative analysis of Al(III) ion was performed by making the complex compound between Al(III) ion and 5-CH3O-PMP in ethanol-water solution (85/15, v/v, pH 6.2). The excitation wavelength (λem) of the complex compound was 397 nm while the emmision wavelength (λem) was 498 nm. The quantitative analysis of Al(III) ion was carried out by estimating the fluorescence intensity. The various calibration curves were used for the quantitative analysis in the range of 0.27∼27 ng/mL Al(III) ion concentrations. The detection limit was 0.027 ng/mL. Using the fluorometric method developed in this study, satisfying results were obtained from various samples such as tap water, hot spring water, river water, sea water and waste water, which contained considerable amounts of interfering ions
[en] An investigation of the fine structure of 3s23p2P and 3s23d2D levels for 54 ions of the isoelectronic series of aluminum using the values of energy levels calculated previously by the Dirac-Fock method is reported. Comparison with experimental data shows that 32P levels of Al-like ions are only weakly perturbed. By contrast, the splitting of the fine structure of 32D levels changes sharply and nonmonotonically along the isoelectronic series, which indicates a strong overlap of configurations. The values of fine-structure splitting calculated for 32D levels with considerations for the overlap of the 3s3p2 configuration are in qualitative agreement with the change of experimental values along the isoelectronic series. 14 refs., 3 figs
[en] We propose a fabrication method for polydiacetylene (PDA)-embedded hydrogel microfibers on a microfluidic chip. These fibers can be applied to the detection of cyclodextrines (CDs), which are a family of sugar and aluminum ions. PDA, a family of conjugated polymers, has unique characteristics when used for a sensor, because it undergoes a blue-to-red color transition and nonfluorescence-to-fluorescence transition in response to environmental stimulation. PDAs have different sensing characteristics depending on the head group of PCDA. By taking advantage of ionic crosslinking-induced hydrogel formation and the 3D hydrodynamic focusing effect on a microfluidic chip, PCDA-EDEA-derived diacetylene (DA) monomer-embedded microfibers were successfully fabricated. UV irradiation of the fibers afforded blue-colored PDA, and the resulting blue PDA fibers underwent a phase transition to red and emitted red fluorescence upon exposure to CDs and aluminum ions. Their fluorescence intensity varied depending on the CDs and aluminum ion concentrations. This phase transition was also observed when the fibers were dried
[en] A new schiff-base receptor L based on naphthalimide had been investigated as a selective and sensitive chemosensor for Al3+ in CH3OH. Upon addition of Al3+, L showed a 39-fold enhancement at 508 nm with colorimetric and fluorometric dual-signaling response which might be induced by the integration of ICT and CHEF. A 1:1 stoichiometry for the L-Al3+ complex was formed with an association constant of 1.62×104 M−1, and the limit of detection for Al3+ was determined as 7.4 nM. In addition, the potential utility of L in sensing Al3+ was also examined in real water samples.
[en] We investigate the non-equilibrium atomic kinetics using a collisional-radiative (CR) model modified to include line absorption. Steady-state emission is calculated for He-like aluminum ions immersed in a specified radiation field having fixed deviations from a Planck spectrum. The net emission is interpreted in terms of NLTE population changes. The calculation provides an NLTE response matrix, and in agreement with a general relation of non-equilibrium thermodynamics, the response matrix is symmetric. We compute the response matrix for 1% and 50% changes in the photon temperature and find linear response over a surprisingly large range