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A newly luminescent nanomaterial, monoclinic wolframite-type HgWO 4 nanoshuttles (length: 200–300 nm; diameter: 100–150 nm) is prepared through ultrasonic method. For HgWO 4 nanoshuttles, the fluorescent (FL) emitting peaks at 430 and 330 nm obviously blue shift compared with those of corresponding bulk crystals. Meanwhile, the latter almost disappear after ultrasonic irradiation procedure. A UV-visible blue-shifted (about 130 nm) absorption peak is observed at 280 nm and a new absorption peak is observed at 203 nm. FTIR results show all absorption peaks below 800 cm-1 shift to a longer wavenumber region, whereas those above 800 cm-1 remain invariable. All those unique optical performances might result from both quantum size effects and the involvement of the incompact d10 electrons. Moreover, the possible synthesis mechanism of HgWO 4 nanoshuttles is also investigated.

For the first time, Cadmium tungstate (CdWO 4 )–TiO 2 composite nanofilms on a glass substrate were prepared by means of the dip-coating technique, in which collodion was used as a dispersant and film-forming agent. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermo gravimetric and thermal analyses (TG/DTA), FTIR and photoluminescence (PL) methods, respectively. SEM and XRD characterization of these films indicated that CdWO 4 particles crystallized in a monoclinic wolframite-type structure whereas TiO 2 particles were Anatase phase; and both of them were well distributed in the nanofilms. FTIR spectra proved the presence of CdWO 4 on the nanofilms. Photoluminescent results showed that the emitting peak of CdWO 4 films blue shifted slightly relative to that of CdWO 4 crystal. Moreover, the PL intensity of CdWO 4 –TiO 2 composite nanofilm was much higher than that of CdWO 4 nanofilm. We ascribed that the introduction of TiO 2 should be responsible for the PL enhancement.

AWO4 (A = Ca, Ba, Sr) nanofilms on a glass substrate are prepared through the combination of the reverse micelle system with the dip-coating technology, in which collodion is used as a dispersant and film-forming agent. The nanofilms are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL) and IR spectra, respectively. The results indicate that the tungstate nanoparticles having a tetragonal scheelite structure are well distributed on the substrate. PL results indicate that a blue-shift emission band peak of the nanofilms appears when they are excited at 240 nm relative to those of the bulk materials, and a red-shift emission band peak of nanofilms appears compared with nanoparticles, which can be attributed to the quantum size effect. IR spectra reveal that a large absorption band, which is ascribed to the W–O stretching vibration in WO4 tetrahedron, is observed around 820 cm−1.

For the first time, the photoluminescence (PL) spectra of porous anodized aluminum oxide (AAO) films impregnated with essentially non-fluorescent 3, 5, 7, 2′, 4′-pentahydroxyflavone (morin) and morin–human immunoglobulin (IgG) were investigated and compared with those of liquid solutions. It was found that their PL band positions are similar to that of morin–Al3+ in ethanol solution, and the PL intensity of embedded morin alone can be enhanced greatly by the introduction of human immunoglobulin. We infer that the appearance of the PL band detected here is due to the formation of morin–Al complex in the holes of AAO with the inner wall involved, and a likely luminescent mechanism is proposed to elucidate the PL enhancement phenomena due to the coexistence of morin and IgG in the AAO pores, which is confirmed by ultraviolet (UV)–visible and Fourier transform infrared (FTIR) measurements. Moreover, it is also found that the PL intensity increases with the pore size.

For the first time, an organic dye, morin, and bio-macromolecule, lysozyme (Lys) were embedded in the holes of anodic porous alumina (P-Al). The photoluminescent (PL) spectra of dye and dye–protein immersed in P-Al film were investigated and compared with those of liquid solutions. It was found that their PL positions are similar to that of dye–Al3+ in ethanol solution, and the PL intensity of embedded dye can be enhanced greatly by the introduction of lysozyme. We ascribe that the appearance of the PL band detected is attributed to the formation of morin–Al complex in the pores with its inner wall involved. A likely orderly model was proposed to explain the observed enhancing phenomena of PL due to the coexistence of morin and lysozyme in the P-Al layer, which has been proved by UV and FTIR measurements.

For the first time, the photoluminescence (PL) spectra of anodic porous alumina (P-Al) films impregnated with essentially non-fluorescent morin and morin–trypsin (Try) were investigated and compared with those of liquid solutions. It was found that their PL positions are similar to that of dye–Al3+ in ethanol solution, and the PL intensity of embedded dye–Try is much higher than that of embedded dye alone. We infer that the appearance of the PL band detected here is due to the formation of morin–Al complex in the holes of P-Al with the inner wall involved, and a likely luminescent mechanism is proposed to elucidate the PL enhancement phenomena due to the coexistence of morin and Try in the P-Al pores, which is confirmed by UV and FTIR measurements. Moreover, it is also found that the PL intensity increases with the pore size.

For the first time, an organic dye, morin, and another bio-macromolecule, human serum albumen (HSA), were embedded in porous alumina (P-Al) fabricated by anodization in oxalic acid. The photoluminescent (PL) spectra of morin and morin–HSA immersed in the P-Al pores were measured and compared with those of liquid solutions. It was found that their PL positions are similar to those of dye-Al3+ in ethanol solution, and the PL of the embedded morin was greatly enhanced by the introduction of HSA. We have ascribed the appearance of PL bands to the formation of morin–Al complexes in the nanopores, with its inner wall being involved. A likely luminescence model was proposed to explain the observed PL enhancement due to the coexistence of morin and HSA in the nanopores, which has been proved by UV and Fourier transform infrared measurements. Moreover, the PL intensity increased with increasing pore diameter, which may be used to develop a luminescent array to predict the pore size of a P-Al layer.

A simple, sensitive and selective method has been developed for the determination of protein using resonance light scattering (RLS) technique. The method is based on the interaction of protein and arsenazo-DBC-Al 3+ in the pH range of 5.0–7.0, which causes a substantial enhancement of the resonance scattering signal of arsenazo-DBC-Al 3+ in the wavelength range of 300–550 nm with the maximum RLS platform at 405–420 nm. With this method, 2.50–50.00 μg ml −1 of bovine serum albumin (BSA) and 2.50–60.00 μg ml −1 of human serum albumin (HSA) can be determined, and the detection limits, calculated three times the standard deviation (S.D.) of six blank measurements, for BSA and HSA were 123.4 and 89.6 ng ml −1 , respectively. Moreover, the method is free from interference from many amino acids and metal ions. The method, with high sensitivity, selectivity and reproducibility, was satisfactorily applied to the determination of total protein in human serum samples. Mechanism studies indicated that arsenazo-DBC-Al 3+ could bind to BSA depending mainly on electrostatic forces, which results in enhanced RLS in the arsenazo-DBC-Al 3+ –protein system.

This paper researched the determination of proteins with 2-(2-arsonophehenylazo)-7-[(2,6-dibromo-4-sulfophenylazo)1,8-dihydroxynaphthalene-3,6-disulfonic acid (Arsenazo-DBS) by Rayleigh light-scattering (RLS). The reaction parameters, such as acidity, volume of buffer solution and concentration of Arsenazo-DBS, were examined by orthogonal array design (OAD). Under optimal conditions, the weak RLS of Arsenazo-DBS and BSA can be enhanced greatly and two enhanced RLS signals were produced at 340-350 and 400-420 run. Based on this reaction, a new quantitative determination method for proteins has been developed. This method is proved to be very sensitive (the determination limits are 0.077 mug ml(-1) for bovine serum albumen (BSA) and 0.074 mug ml(-1) for human serum albumen (HSA)), rapid (

Electrophoretic mobility ( μ 0 ) is the most important parameter governing the separation of solutes in capillary zone electrophoresis. In this paper, a new model was constructed by means of a multilayer neural network using extended delta-bar-delta (EDBD) algorithm to estimate complex property of electrophoretic mobilities of aliphatic carboxylates and amines from simpler experimental properties. The molecular weight ( W ), molecular volume ( V ), the code (+1 or −1) of acid and base and p K value were used as input parameters to predict electrophoretic mobility. The networks' architecture and the learning times were optimized. The optimum artificial neural networks (ANNs) could give excellent prediction results.

Flexible thermoelectric composite films of polypyrrole (PPy) nanotubes coated paper were fabricated by an in-situ polymerization procedure using methyl orange as a template and paper as the substrate for the first time. Both the electrical conductivity and Seebeck coefficient of the polypyrrole nanotubes coated paper composite films have been enhanced (from ~0.048 S/cm to ~0.068 S/cm and from ~5.34 μV/K to ~8.21 μV/K for the average value for three measurements, respectively) as the temperature increased from ~300 K to ~370 K, which lead to the same trend of the power factor. The thermal conductivity of the polypyrrole nanotubes coated composite films was very low (~0.1275 W·m−1·K−1 at ~300 K), and a highest ZT (material’s dimensionless figure of merit (S2σT/κ)) value of 3.2 × 10−7 was obtained at ~370 K.

Flexible poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/polypyrrole/paper (PEDOT:PSS/PPy/paper) thermoelectric (TE) nanocomposite films were prepared by a two-step method: first, PPy/paper nanocomposite films were prepared by an in situ chemical polymerization process, and second, PEDOT:PSS/PPy/paper TE composite films were fabricated by coating the as-prepared PPy/paper nanocomposite films using a dimethyl sulfoxide-doped PEDOT:PSS solution. Both the electrical conductivity and the Seebeck coefficient of the PEDOT:PSS/PPy/paper TE nanocomposite films were greatly enhanced from 0.06 S/cm to ~0.365 S/cm, and from 5.44 μV/K to ~16.0 μV/K at ~300 K, respectively, when compared to the PPy/paper TE nanocomposite films. The thermal conductivity of the PEDOT:PSS/PPy/paper composite film (0.1522 Wm−1K−1 at ~300 K) was, however, only slightly higher than that of the PPy/paper composite film (0.1142 Wm−1K−1 at ~300 K). As a result, the ZT value of the PEDOT:PSS/PPy/paper composite film (~1.85 × 10−5 at ~300 K) was significantly enhanced when compared to that of the PPy/paper composite film (~4.73 × 10−7 at ~300 K). The as-prepared nanocomposite films have great potential for application in flexible TE devices.

Based on the weak Rayleigh light scattering (RLS) of the complex of dibromomethyl (DBM)–Arsenazo–Al(III) which can be enhanced by the addition of protein in weak acidic solutions, a novel method for the determination of protein concentrations has been proposed by using a commonly used spectrofluorimeter. Four proteins, including bovine serum albumin (BSA), human serum albumin (HSA), lysozyme and egg albumin were tested. The dynamic range, for example HSA is 2.5–50.0 μg ml −1 and the 10 σ determination limit is 83 ng ml −1 . This method has been applied to the determination of proteins in human serum samples, and the results are very close to those provided by clinical physicians. There is very little interference from amino acids, metal ions and other coexisting compounds. The assay is convenient, rapid, inexpensive and simple.

Based on the enhancement effects of Rayleigh light scattering (RLS) on Arsenazo-DBC, a novel quantitative method for the determination of proteins in aqueous solutions has been proposed. The reaction of Dibromochloroarsenazo (Arsenazo-DBC) and five proteins (BSA, HSA, egg albumin, human γ-IgG, Lysozyme) has been studied. Under optimal conditions the dynamic ranges for proteins were 2.5–60.0 μg·ml−1, and the detection limits for HSA and BSA were at 98.50 ng·ml−1 and 88.10 ng·ml−1, respectively. Comparing with other methods, the method is simple, practical and relatively free from interference from coexisting substances. The method was employed for the determination of total protein in human serum with satisfactory results.

In this paper, the photoluminescence (PL) of porous anodized aluminum oxide (AAO) impregnated with essentially nonfluorescent morin and morin–bovine serum albumin (BSA) was investigated for the first time, respectively. The evident PL bands similar to that of morin–Al3+ complex in solution were observed and the intensity of the latter with morin–BSA was much greater than that of the former with only morin. Moreover, the enhancement increased with the larger pore diameter of the AAO membranes. The appearance of PL bands might be ascribed to the formation of morin–Al complexes in the AAO pores with its inner wall involved. A likely orderly luminescent model was proposed to be responsible for the observed enhancing phenomena of PL due to the coexistence of morin and BSA in the AAO pores.

Plasma-induced graft polymerization was used to modify carbon nanotubes(CNTs),in which maleic anhydride(MAH) was used as polymeric monomer and argon as plasma source.The polymer film-modified CNTs(p-CNTs) were introduced into epoxy resin(EP) to obtain p-CNT/EP composites and their effects on EP properties were studied.The p-CNTs were characterized by FTIR and scanning electron microscopy.Results show that maleic anhydride can be graft polymerized onto the surface of CNTs using the plasma technique,forming a uniform polymaleic anhydride(PMAH) film.The mechanical properties of EP were greatly improved by adding p-CNTs.

The determination of proteins with tetrasodium 2-(3,6-disulfo-8-hydroxynaphthylazo)-1,8-dihydroxynaphthalene- 3,6-disulfonate (Beryllon II) by Rayleigh light scattering (RLS) was studied. The weak RLS of the Beryllon II–bovine serum albumin (BSA) complex can be greatly enhanced by the addition of Al3+ in the pH range 5.6–7.2; there was a maximum RLS platform at 400–420 nm. Based on the reaction between Beryllon II, Al3+ and proteins, a new method for the determination of proteins was developed. This method is very sensitive [0.20–41.42 μg ml−1 for BSA and 0.18–48.15 μg ml−1 for human serum albumen (HSA)], rapid (

Nanometer sized lead molybdate (PbMoO4) plates are prepared through conventional hydrothermal together with sonochemical methods. The plates are then characterized using field-emission scanning electron microscopy, X-ray diffractometry, Fourier transform infrared (FTIR) spectrometry, photoluminescence spectrometry, and ultraviolet-visible (UV-VIS) spectrometry. The results indicate that the nanoplates have a characteristically narrow particle size distribution and their tetragonal scheelite-type structure is confirmed by both X-ray diffractometry and FTIR spectrometry. When the nanoplates are compared with the corresponding bulk crystals, blue shifts in their photoluminescence peaks, wider optical band gaps, and the broadening of the X-ray diffractometer peaks are observed. These can be ascribed to the decrease in crystal size.

AWO4 (A=Ca,Sr,Ba) nanofilms are prepared by a self-inventive technique using collodion to disperse nanoparticles and form film, and their photoluminescence (PL) properties are controlled by a nano-TiO2 doping method. This cannot only reach the results of uniform film and PL enhancement, but also realize a PL increase/decrease shift effect. The PL behaviors of AWO4 nanofilms doped by TiO2 are in good agreement with Gaussion function relation. In addition, there is a positive correlation between the critical concentrations of TiO2 in AWO4–TiO2 nanofilm series and A’s ionic potential.