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Porous graphene materials show outstanding performance in energy storage field due to their unique microstructure and properties. To construct 3D hierarchical porous graphene and combine with conductive polyaniline is an effective way to realize high energy density and good cycling stability. The interlamellar macroporous structure of 3D graphene was constructed by polystyrene (PS) microspheres and nickel foam as double templates. The mesoporous structure was etched in 3D macroporous graphene sheets by potassium hydroxide (KOH) chemical activation. And 3D hierarchical porous graphene (3D-hpGr) composited with polyaniline (PANI) by in situ chemical oxidative polymerization to obtain 3D-hpGr/PANI composites. The effect of the introduction of 3D-hpGr on microstructure, morphology and electrochemical performance of the composites was investigated. PANI nanowire arrays successfully decorate the surface of the 3D-hpGr sheets when the amount of 3D-hpGr reaches 40% (wt%). The specific capacitance of 3D-hpGr/PANI40 reaches 573 F g−1 at 0.5 A g−1, much higher than that of pure PANI (419 F g−1). The retention ratio of 3D-hpGr/PANI40 retains 84% of its initial specific capacitance after 1000 cycles at 1.0 A g−1, and the cycling stability of all composites is higher than that of pure PANI (69%). The potential drop of 3D-hpGr/PANI composites decreases from 0.339 V to 0.139 V, and the energy density increases consequently. The energy density of 3D-hpGr/PANI40 reaches 31.2 W h kg−1 at the power density of 0.709 kW kg−1.

Cadmium (Cd), a ubiquitous toxic heavy metal, with the intractable trait of low degradation, can induce multiple organ damage. Whereas, far less is known about its neurotoxicity and the specific mechanism in the chronic low Cd exposure. To investigate the chronic neurotoxicity of Cd

Improved optical and mechanical properties are required for future infrared windows working in harsher mechanical and thermal environments than today. Ameliorating the homogeneity of the phase domain and reducing the size of the phase domain are effective approaches for enhancing the optical transmittance and mechanical hardness of a nanocomposite. In this work, we reported that the Gd2O3-MgO nanopowders were prepared by two different processes. The core–shell nanopowders synthesized by urea precipitation have a much lower agglomeration than the nanopowders prepared by sol–gel. Excellent transmittance (70.0%–84.1%) at 3–6 μm mid-infrared wave range and a high Vickers hardness value (10.3 ± 0.6 GPa) were maintained using the nanopowders synthesized by urea precipitation mainly due to its homogenous phase domain distribution.

An easy approach is described for the preparation of ZrO2-coated Y2O3 nanopowder from a solution of zirconium nitrate with commercial Y2O3 nanopowder. The evolution process of the ZrO2 coating layer upon calcination, such as the phase and microstructure of the particles’ surface, was studied. Calcination of the powder at 700 °C resulted in ZrO2-coated Y2O3 nanopowder. The rheological properties of the suspensions of ZrO2-coated Y2O3 powders were studied. A well-dispersed suspension with a solid loading of 35.0 vol% using ZrO2-coated Y2O3 nanopowder was obtained. The consolidated green body obtained by the centrifugal casting method showed improved homogeneity with a relative density of 50.2%. Transparent ceramic with high transparency and an average grain size of 1.7 µm was obtained by presintering at 1500 °C for 16 h in air, followed by post-HIP at 1550 °C for 2 h under 200 MPa pressure. The in-line transmittance at the wavelength of 1100 nm (1.0 mm thick) reached 81.4%, close to the theoretical transmittance of Y2O3 crystal.

As the rapid growth of supercapacitor industry, there are increasing demands for aqueous dispersible and environmentally friendly polymer binders to manufacture graphene electrodes with high capacitance, long lifetime, and great mechanical flexibility. Here, four different binders were selected to study the effect on structural and electrochemical performance of the reduced graphene oxide (rGO) thin film electrodes. The four binders include two fluorinated polymers, a conductive binder formulation, and a water-based elastomeric binder. The morphology, crystallinity, thermal stability, and hydrophilicity of the electrode films were characterized. Electrochemical measurements were carried out to compare capacitance, resistance, and frequency response of the electrodes with various binders. Results reveal that the rGO with conductive binders showed the highest capacitance with low internal resistance in both aqueous and organic electrolytes; while the rGO bound by elastomeric binder exhibited excellent cycling stability, low charge transfer resistance, and low relaxation time constant in aqueous electrolyte. Moreover, it was found that that binders with high conductivity and enhanced compatibility with electrolytes can facilitate ionic diffusion within the porous structure of electrodes, which leads to faster frequency response and better capacitive properties.

Tungsten oxide thin films were deposited at room temperature under different negative bias voltages (Vb, 0 to −500 V) by DC reactive magnetron sputtering, and then the as-deposited films were annealed at 500 °C in air atmosphere. The crystal structure, surface morphology, chemical composition and transmittance of the tungsten oxide thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and UV–vis spectrophotometer. The XRD analysis reveals that the tungsten oxide films deposited at different negative bias voltages present a partly crystallized amorphous structure. All the films transfer from amorphous to crystalline (monoclinic + hexagonal) after annealing 3 h at 500 °C. Furthermore, the crystallized tungsten oxide films show different preferred orientation. The morphology of the tungsten oxide films deposited at different negative bias voltages is consisted of fine nanoscale grains. The grains grow up and conjunct with each other after annealing. The tungsten oxide films deposited at higher negative bias voltages after annealing show non-uniform special morphology. Substoichiometric tungsten oxide films were formed as evidenced by XPS spectra of W4f and O1s. As a result, semi-transparent films were obtained in the visible range for all films deposited at different negative bias voltages.

Over the past few years, supercapacitors based on graphene/polyaniline (rGO/PANI) composites have gained immense attention. The electrochemical performance of rGO/PANI composites can be improved by controlling their morphology and structure. However, very few studies have been carried out on amine-functionalized graphene/polyaniline (F-rGO/PANI) composites. In this study, amine-functionalized graphene (F-rGO) and mesoporous graphene (PF-rGO) were composited with PANI. The results showed that the specific capacitance of the F-rGO/PANI composites could be improved by controlling their morphology. The mesoporous structure of F-rGO contributed to the improvement in the cycling stability and energy density of the composites. At a current density of 0.5 A g−1, the specific capacitances of F-rGO/PANI20–0.5h and PF-rGO/PANI are 597 F g−1 and 489 F g−1, respectively; these values are remarkably higher than that of pure PANI (400 F g−1). F-rGO/PANI20-0.5th and PF-rGO/PANI maintained specific capacitances of 75% and 89%, respectively, which were significantly higher than that of pure PANI; this was observed even after 2000 cycles of charge and discharge had been completed at a current density of 1 A g−1. The energy density of PF-rGO/PANI reaches 34.9 W h kg−1 at the power density of 1.27 kW kg−1. This study is expected to provide an effective basis for the future research of graphene-based composite electrode materials for supercapacitors.

Oxyfluoride tellurite glasses with compositions of TeO2–Al2O3–CaF2/BaF2–NaF–YbF3–xHoF3 (x = 0.1, 0.3, 0.5, 1.0, 1.5, 2.0 mol%) were prepared by conventional melt-quenching method. Effect of heat-treatment schedules on crystallization behavior and microstructure were analyzed by differential scanning caborimetry, X-ray diffraction, infrared spectra and scanning electron microscopy. Cubic CaF2 and BaF2 nano-crystal phases were formed by controlling heat-treatment schedules. Up-conversion emission properties and mechanism of Yb3+ and Ho3+ ions in glasses and glass–ceramics were investigated. The green and red up-conversion emissions were observed under 980 nm LD excitation. Up-conversion luminescence intensity in glasses was obvious higher than that in glass–ceramics. And there existed concentration quenching effect among Ho3+ ions resulted from cross-relaxation.

Graphite oxide was prepared via the modified Hummers’ method and graphene via chemical reduction. Deoxygenation efficiency of graphene oxide was compared among single reductants including sodium borohydride, hydrohalic acids, hydrazine hydrate, and vitamin C. Two-step reduction of graphene oxide was primarily studied. The reduced graphene oxide was characterized by XRD, TG, SEM, XPS, and Raman spectroscopy. Square resistance was measured as well. Results showed that films with single-step N2H4 reduction have the best transmittance and electrical conductivity with square resistance of ~5746 Ω/sq at 70% transmittance. This provided an experimental basis of using graphene for electronic device applications.

Phase transformation of TiO2 powder (P25) and pure anatase (PA) was investigated under pure oxygen as well as vacuum from 500 to 1,000 °C. The rutile percentage calculated based on the XRD data was used to estimate the phase transformation process. It was found that the vacuum suppressed the phase transformation of P25 relative to pure oxygen atmosphere. A model was proposed to explain the effect of oxygen on the phase transformation of TiO2. Furthermore, P25 samples showed lower phase transformation temperature (between 600 and 800 °C) compared with PA (over 1,000 °C). The existed rutile phase in P25 was regarded as a transformation inducer due to an interface between anatase and rutile phases since the nucleation activation energy on the interface is lower than that on the surface. And this interface effect is also adopted to explain the role of additive WO3, which retarded the phase transformation of P25 but promoted the phase transformation of PA.

A noval anilino-pyrimidine fungicide, pyrimethanil butanedioic salt (C28H32N6O4), was synthesized by a chemical reaction of pyrimethanil and butanedioic acid. The low-temperature heat capacities of the compound were measured with an adiabatic calorimeter from 80 to 380 K. The thermodynamic function data relative to 298.15 K were calculated based on the heat capacity fitted curve. The thermal stability of the compound was investigated by TG and DSC. The TG curve shows that pyrimethanil butanedioic salt starts to sublimate at 455.1 K and totally changes into vapor when the temperature reaches 542.5 K with the maximal speed of weight loss at 536.8 K. The melting point, the molar enthalpy (Δfus H m), and entropy (Δfus S m) of fusion were determined from its DSC curves. The constant-volume energy of combustion (Δc U m) of pyrimethanil butanedioic salt was measured by an isoperibol oxygen-bomb combustion calorimeter at T = (298.15 ± 0.001) K. From the Hess thermochemical cycle, the standard molar enthalpy of formation was derived and determined to be Δf H m o (pyrimethanil butanedioic salt)=−285.4 ± 5.5 kJ mol−1.

The lamination of green ceramic tapes is the basis of the production of multilayer ceramic devices. In this paper, cordierite green ceramic tapes are laminated by applying pressures directly at ambient temperature. As a first attempt, the effect of pressure, layers, dwell time on lamination and the sintering temperature on laminates are investigated. It is shown that pressure makes the greatest effect on lamination and dwell time is not obvious. The effect of layers on lamination is mainly related to the pressure that is executed on tapes, and the sintering temperature is contributed to the dense of laminates. The pressure of lamination is not high, and the tapes do not need to be heated. Taking a pressure-assisted method, the deformation of laminates during sintering can be avoided, and a better lamination effect is acquired. The lamination and pressure-assisted methods are both of low cost and simple and feasible to work.

Cordierite is a promising material in the fields of high frequency multilayer ceramic components and ceramic package substrates. In this paper, cordierite green tapes were cast by aqueous tape casting with own formula. The characteristics of cordierite tapes such as phase transformation, sintering properties and dielectric properties were studied. Co-firing behavior of cordierite tape and Ag—Pd conductive metal was investigated tentatively. It was shown that the cordierite tapes can be sintered at 900 °C and the main crystalline phase is α- cordierite. The sintered tapes have good density, low dielectric constant ( e =3.4993; 2 GHz)and low dielectric loss (tg δ =0.0063; 2 GHz). There is good co-firing compatibility between cordierite and Ag—Pd conductive metal in the sintering process. The low temperature sintering, low dielectric cordierite tapes can be used as a potential material for high frequency application.

Transparent oxyfluoride tellurite glasses with composition of TeO2–SiO2–AlF3–CaO–NaF–ErF3–HoF3 were prepared by a conventional melt-quenching method. Hexagonal β-NaCaAlF6 nano-crystal phase was formed after heat-treatment. Er3+ and Ho3+ ions remain in the residual glass phase after crystallization. Luminescence properties and up-conversion emission mechanism were investigated. Luminescence intensity of Er3+ at 1.53 μm reduced gradually along with the increase of Ho3+ ions concentration both for glasses and glass–ceramics. The green and red up-conversion emissions were observed under 980 nm excitation. With the increase of the Ho3+ ions concentration, the green emission intensity decreased monotonously and the red emission intensity increased obviously, there existed energy transfer between Er3+ and Ho3+ ions, (1) Ho3+(5I8) + Er3+(4I11/2) → Ho3+(5I6) + Er3+(4I15/2), (2) Ho3+(5I6) + Er3+(4I11/2) → Ho3+(5F3) + Er3+(4I15/2), (3) Ho3+(5I6) + Er3+(4I13/2) → Ho3+(5F5) + Er3+(4I15/2). The decrease of red emission intensity at 3.0 mol% of Ho3+ ions was mainly due to the cross-relaxation among Ho3+ ions, Ho3+(5F3) + Ho3+(5I8) → Ho3+(5F5) + Ho3+(5I6).

Nano-Cordierite powders used for high frequency chip inductors (MLCIs) were prepared by sol–emulsion–gel method. Effects of precursor concentration and [H 2 O]/[Si] molar ratio on this material were studied. The sol–emulsion–gel processing of Mg 2 Al 4 Si 5 O 18 as well as its dielectric property were investigated. Owing to the better packing efficiency and therefore higher surface energy of the freestanding nano-powder, the pressed pellets made by cordierite powder showed 98.6% theoretical density at 900 °C for 2 h. The additive Bi 2 O 3 was utilized to promote the crystallization or transformation to α-cordierite and sintering. The sol–emulsion–gel-derived cordierite ceramics have low dielectric constant ( e =3.0∼4.0; 18 GHz) and low dielectric loss ( tgδ

Novel anilino-pyrimidine fungicides, pyrimethanil maleic salt, and pyrimethanil fumaric salt (C28H30N6O4) were synthesized by a chemical reaction of pyrimethanil with maleic acid/fumaric acid. The low-temperature heat capacities of the two compounds were measured with an adiabatic calorimeter from 80 to 350 K. The heat capacities of pyrimethanil fumaric salt are bigger than that of pyrimethanil maleic salt in the measurement temperature range. The thermodynamic function data relative to 298.15 K were calculated based on the heat capacity-fitted curves. The melting points, the molar enthalpies (Δfus H m), and entropies (Δfus S m) of fusion of pyrimethanil maleic salt and pyrimethanil fumaric salt were determined from their DSC curves. The values indicate that pyrimethanil fumaric salt was more thermostable than pyrimethanil maleic salt. The constant-volume energies of combustion (Δc U m o ) of pyrimethanil maleic salt and pyrimethanil fumaric salt were measured using an isoperibol oxygen bomb combustion calorimeter at T = (298.15 ± 0.001) K. From the Hess thermochemical cycle, the standard molar enthalpies of formation of the two compounds were derived and determined to be Δf H m o (pyrimethanil maleic salt) = −459.3 ± 4.9 kJ mol−1 and Δf H m o (pyrimethanil fumaric salt) = −557.2 ± 4.8 kJ mol−1, respectively. The results suggest that pyrimethanil fumaric salt is more chemically stable than pyrimethanil maleic salt.

Transparent glass–ceramics in TeO 2 –SiO 2 –AlF 3 –CaO–NaF–ErF 3 system were prepared. Effect of heat-treatment schedules on crystallization behavior and microstructure were analyzed by differential scanning caborimetry, X-ray diffraction, infrared spectrum and scanning electron microscopy. The sole CaF 2 nanocrystal phase was confirmed, grains were spherical and distributed uniformly. Te and Si atoms existed in [TeO 3 ] and [SiO 4 ] forms. The full width at half maximum at 1533 nm emission increased from 39.16 nm to 43.37 nm after crystallization. Er 3+ ions were incorporated into CaF 2 nanocrystals with low phonon energies. The transmittance of glass–ceramics reached 78% at 780 nm and 90% at 1017 nm.

Stereology was applied to study quantitative relationship between stereological parameters in three-dimensional Euclidean space and light transmittance of Nd:YAG ceramics prepared by the vacuum sintering at 1700 °C for 5 h. The ceramic materials were characterized by light transmittance, field emission gun-environment scanning microscope. The micrographs of ceramic surface were analyzed by the metallographic software to obtain the frequency distribution of grains. It was found that the transmittance of Nd:YAG 1 mm in thickness is about 45% and 58% in visible and near-infrared wavelength, respectively. The transmittance linearly increases with increasing equivalent sphere diameter and reaches theoretical value of single crystal when the equivalent sphere diameter is 20 μm. The transmittance decreases with increasing of mean specific area per unit volume of grain and discrete grains and mean free distance.

Lithium aluminosilicate (LAS) glasses are generally difficult to prepare because of their high melting temperature. In this study, the preparation of LAS glasses was achieved at a relatively low melting temperature. The batch containing MgO-ZnO-Li2O-Al2O3-SiO2 was melted in a platinum crucible at 1550°C for 2 h and was then followed by two- or three-step heat treatment processes for nucleation and crystal growth. The characterizations were carried out by differential thermal analysis, X-ray diffraction, infrared spectroscopy, scanning electron microscopy, and UV-Vis-NIR scanning spectrophotometry. The hexagonal stuffed β-eucryptite solid solution crystallized at 840–960°C. Most of the hexagonal β-eucryptite solid solution transformed into the tetragonal β-spodumene solid solution at 1100°C. Almost all the aluminum atoms entered into the tetrahedral sites in the aluminosilicate network of the β-eucryptite/β-quartz solid solution. All of the Al atoms did not belong to the aluminosilicate network of the β-spodumene solid solution. The glass ceramic with a mean grain size of 10–20 nm is transparent, the transmittance reaches ∼85% in the visible light wavelength.

Nd:YAG precursor powders were synthesized by homogeneous precipitation, and Nd:YAG transparent ceramics were prepared by vacuum sintering at 1700 °C for 5 h. The ceramic materials were characterized by light transmittance and field emission gun-environment scanning microscope. Using statistics and stereology theory, study was carried out on the quantitative relationships between light transmittance and stereological parameters in three-dimensional Euclidean space. It is found that the transmittance of Nd:YAG with 1 mm in thickness is about 45% and 58% in visible and near-infrared wavelength, respectively. The transmittance linearly increases with increasing equivalent sphere diameter and reaches the theoretical value of single crystal when the equivalent sphere diameter is 20 μm. The transmittance decreases with the increasing of mean specific area per unit volume of grain and discrete grains, and the transmittance decreases with increasing mean free distance of grains in Nd:YAG ceramics.

Generally the preparation of lithium aluminosilicate (LAS) glasses is difficult on account of their high melting temperature. This research managed to prepare LAS glasses doped with Nd3+ ions by the conventional melting and quenching technique, at a relatively low melting temperature and by the use of some additives. Lithium aluminosilicate glasses were transformed to glass-ceramics by controlled nucleation and the crystallization process. The characterizations were performed by differential thermal analysis, X-ray diffraction, UV-Vis-NIR scanning spectrophotometry, and fluorescence spectrometry. The research focused on the photoluminescence spectra of the initial glass and the glass-ceramics under different heat-treatment schedules. Three main fluorescence bands centering at about 890, 1065, and 1330 nm were observed, which corresponded to the transitions of 4F3/2→4I9/2, and 4F3/2→4I11/2, and 4F3/2→4I13/2, respectively. Phase compositions of glass-ceramics were found to affect their fluorescent characteristics considerably. The fluorescent intensity increased markedly when Nd3+ ions entered the LixAlxSi1-xO2 β-eucryptite solid solution (SS). Quenching occurred when Nd3+ ions located at LixAlxSi3-xO6 β-eucryptite SS. Quenching disappeared after LixAlxSi3-xO6 β-eucryptite SS recrystallized into β-spodumene SS. The effectively induced cross section σin of Nd3+ ions located at the LixAlxSi1-xO2 β-eucryptite SS was 1.931 × 10−21 cm2 at 1065 nm.

This document shows the desired format and appearance of a manuscript prepared for the Proceedings of the ICO20. It contains general formatting instructions and hints about how to use it. The (Y0.99Nd0.01)3Al5 O12 nano-sized powders were synthesized by low temperature combustion (LCS), using Nd2O3, Y2O3, Al(NO3) 3♦9H2O, ammonia water and citric acid as starting materials. This method effectively solves the problems caused by solid-state reaction at high temperature and hard agglomerates brought by chemical precipitation method. The powders were characterized by TG-DTA, XRD, TEM respectively. The study focused on the photoluminescence (PL) spectra of (Y0.99Nd0.01)3Al5 O12 ceramic green and sintered disks. The experiments show that the forming temperature of YAG crystal phase is 850°C and YAP crystal phase appearing during the calcinations transforms to pure YAG at 1050°C. The particle size of the powders synthesized by the LCS is in range 20-50nm depending on the thermal treatment. The effectively induced cross section (σin) with the value 4.03×10-19cm2 of (Y0.99Nd0.01)3Al5 O12 ceramics is about 44% higher than that of single crystal.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.