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Lithium-ion batteries (LIBs) have been used as energy storage devices for appliances of a wide range of sizes, for example, mobile phones, laptops, and electric vehicles. However, current commercial electrode materials in LIBs are facing severe challenges in energy density, safety, price, and recyclability, and this energy storage technology needs to be further developed for high power application in future. To address this challenge, nanostructured materials which possess large surface-to-volume ratios have been intensively studied as potential electrode materials to improve the battery performance. Among them, Tin (Sn) and nanostructured TiO2 have shown some advantages and disadvantages as electrode materials, for example Sn has high storage capacity but suffer from severe volume expansion during lithiation/delithiation. On the other hand, nanostructured TiO2 has small volume changes during Li ion insertion/extraction, but the poor ion mobility and electronic conductivity limited it electrochemical application. This review summarizes the recent development on Sn and TiO2 based nanostructure materials, particularly the synthesis method, their structure and battery performance as anodes for LIBs. Then, we discuss the strategies of developing new electrode materials and highlight a hybrid approach for designing and synthesizing high-performance electrode materials. The latest developments and related electrochemical performance of anode materials demonstrate that design hybrid nanostructure material is a low-cost and scalable approach to produce high-performance electrode materials for high-energy LIBs.

In aluminum smelting cells, ledges freeze on to cell walls from the cryolitic bath when the temperature drops below the bath liquidus point. Modern cell design and control cause a suitable ledge profile to form and be maintained, in order to protect the cell walls from corrosive liquids (molten salts and Al metal) and ensure efficient current distribution and cell heat balance. During cell operation, a significant ledge, freezing and melting does occur following heat balance changes due to batch operations. The ledge formation mechanism has been studied at the laboratory scale in our previous work. It shows a linkage between the rate and directional nature of ledge growth and its structure as affected through a superheat change. An open ledge structure can dominate the laboratory ledge material growth or melt it out quickly when the superheat either decreases or increases, respectively. This paper begins the investigation of industrial ledge samples, in terms of structure and composition, primarily to identify whether the same ledge formation mechanism exists in industrial cells. In this study, as expected, the industrial ledge shows more complexity than the laboratory ledge; the open structure is different compared to the laboratory ledge due to the inclusion of carbon dust, a large thermal gradient across the ledge, and sufficient aging of the ledge in the cell. The comparison between the laboratory ledge and the industrial ledge has provided insight into the ledge growth mechanism in aluminum smelting cells.

A new 10BaO–40ZnO–15B2O3–35P2O5 (wt%) glass–ceramic with ultra-low permittivity and excellent thermal stability were fabricated by solid-state reaction method. The sintering, phase composition, microstructure and microwave dielectric properties of the glass–ceramics were studied through XRD, SEM, density and dielectric property measurement. The result shows BaZn2(PO4)2 precipitates first at low sintering temperature of 550 °C, and with increasing sintering temperature, Zn3(PO4)2 and Zn3(BO3)2 phases come out in succession in the glass. The bulk densities of the glass–ceramics firstly increase and then decrease with the increment of firing temperature and the highest density can be achieved at 700 °C. The glass–ceramics sintered at 700 °C for 2.5 h possesses the optimal dielectric properties of er = 4.16, Q × f = 12,250 GHz (13.6 GHz), and τf = − 1.5 ppm/°C. Moreover, the samples have good chemical compatibility with silver electrodes, which indicates that the developed glass–ceramic materials are suitable for LTCC applications.

Anode cover material (ACM) partly fuses at the bottom where it interacts with anode and bath in the aluminium reduction cell. This consolidated material is defined as the top crust in the cell, and plays a crucial role in maintaining heat balance, protecting the carbon anode from air-burning and absorbing the fluorides evaporation in the cells. Previous studies have been conducted to illustrate the crust formation and properties. However, there is rarely a systematic structural analysis of crust in the vertical direction due to the complexity and inhomogeneity of industrial crust. In the present study, the phase composition of crust was systematically analysed in the vertical direction, and five zones were identified based on the phase composition. Furthermore, two types of particles are identified in top zone (1) namely: smelter grade alumina (SGA) and crushed bath particles (CBPs). A systematic analysis on CBPs have shown four types of structural features.

This study presents experimental data of CO2 flow condensation heat transfer for mass fluxes ranging from 100 to 500 kg/m2-s inside a 4.73 mm inside diameter, smooth horizontal copper tube, at saturation temperatures between −10 and 0 °C under a wide range of vapour quality conditions. Experimental data were obtained from an open-loop test rig which discharged high-pressure CO2 liquid from bottles to the atmosphere. Experimental results showed that when the test mass flux was greater than or equal to 300 kg/m2-s, for vapour qualities greater than 0.4, the rate of heat transfer increased with increasing mass flux and vapour quality, and increased with decreasing saturation temperature. The flow regimes under these working conditions were predicted as annular from the values of the Soliman Froude number (Frso > 14). Three recently proposed CO2 flow condensation models from the open literature were evaluated against the data from the current experiment. Overall, the model of Li and Norris (2016) gave the most accurate predictions, but under-predicted the low Nusselt number heat transfer rates. This model was modified using the current data, and then re-evaluated against experimental data from the current and other experiments, and was found to have a mean absolute percentage deviation of 7%.

Substitution-induced modifications in structural, magnetic and optical properties of Nb doped and Sm–Nb co-doped BiFeO3 nanoparticles are reported. X-ray diffraction and Raman analyses indicate that the phase transforms from a rhombohedral to orthorhombic one due to Nb doping and Sm–Nb co-doping. The Nb doping and Sm–Nb co-doping both can lead to a decrease in particle size and an enhancement in magnetic properties, but there is a much stronger effect for the Sm–Nb co-doping than for the Nb doping. With increasing doping concentration of Nb and Sm, the maximum and remanent magnetizations first increase and then drop down, i.e., there is a maximum value in both maximum and remanent magnetizations. The optimal maximum and remanent magnetizations are obtained as 0.601 and 0.155 emu/g, respectively, at y = 0.05 for BiFe1 - y Nb y O3 nanoparticles, while they are 0.954 and 0.206 emu/g at x = 0.15 for Bi1 - x Sm x Fe0.95Nb0.05O3 nanoparticles. Meanwhile, the corresponding optical energy band gap of these samples decreases from 2.16 to 2.02 eV with increasing Sm–Nb co-doping concentration, indicating a strong absorption of visible light. Consequently, the magnetic and optical properties of BiFeO3 nanoparticles can be improved considerably by doping high-valence transition and rare earth elements.

We report the first successful field trial of real-time coherent 400G single-carrier superchannel of 1.2Tb/s over distances up to 250 km using production grade 64GBaud DP – 16QAM optical transponders. Stable error-free performance has been demonstrated, co-propagating alongside multiple mixed modulation format 200G single-carrier superchannels (DP – 16QAM, DP – 8QAM, and DP – QPSK) and conventional 40G and 100G optical channels. We demonstrated the transmission of an ultra efficient 1.2Tb/s superchannel with a spectral efficiency of 6.25bit/s/Hz, which is an improvement of 56% over 200G single-carriers in a standard 50GHz grid. We have also shown the impact of optical fiber nonlinearity on both optical performance and achievable spectral efficiency, key parameters that determine the maximum capacity that can be achieved over optical fiber transmission.

Carbon dioxide (CO2) has emerged as an excellent substitute natural refrigerant for low temperature refrigeration applications, but a better understanding of its in-tube flow condensation is needed in order to achieve its full potential. From experimental studies in the open literature we review the effects of mass flux, vapour quality and saturation pressure on CO2 flow condensation heat transfer, frictional pressure drop and flow regime transition inside smooth, micro-fin and microchannel tubes. Successful condensation models which were developed from experiments with other refrigerants are evaluated against the CO2 flow condensation experimental data. Comparison between the predicted and experimental data shows that the unique thermophysical properties of CO2 at high reduced pressure conditions lead to these correlations having high prediction errors on the flow condensation heat transfer inside smooth tubes and microchannels, but have less significant effects on the flow condensation heat transfer and two-phase frictional pressure drop under high mass flux conditions inside micro-fin tubes. Recommendations for condensation and pressure drop models to apply to CO2 flow condensation in different tubes are made. As there is inconsistency between the experimental data in smooth tubes from different sources, and the effects of microchannel and micro-fin tube geometries, on the flow regime transition and condensation heat transfer of CO2, are unclear, a more extensive range of the experimental data in different tubes is needed for a fully understanding of in-tube CO2 flow condensation.

The secondary carry-over of the droplet and liquid film in the steam-water separator can influence the separation efficiency of the separator. The generation of the secondary droplets resulting from droplets impacting the water film of the wetted surface is one of the mechanisms of secondary carry-over. Therefore, the experimental investigation on water droplet impacting liquid film on inclined wetted surface is conducted through high-speed video camera. The subsequent form and evolution process once the droplet colliding with the inclined liquid film are obtained. The droplet splashing phenomenon and mechanism are explained. The qualitative analysis of influence of the initial droplet diameter, velocity and the inclination angle of the wet surface on the splashing behavior is conducted. The results reveal that with increasing angle of inclination of the wet surface, the critical velocity to generate the splashing phenomenon increases accordingly; the increasing initial droplet diameter leads to decreasing critical velocity; the splashing phenomenon is more likely to appear in cases with higher impacting velocity, larger initial droplet diameter and smaller inclination angle, under which conditions the number of secondary droplets generated increases and the splashing phenomenon is more obvious. The obtained experimental results are significant to the study of steam-water separation and can lay basis on design of the separator.

A facile chemical deposition method has been adopted to prepare cerium fluoride (CeF 3 ) surface modified LiNi 1/3 Co 1/3 Mn 1/3 O 2 as cathode material for lithium-ion batteries. Structure analyses reveal that the surface of LiNi 1/3 Co 1/3 Mn 1/3 O 2 particles is uniformly coated by CeF 3 . Electrochemical tests indicate that the optimal CeF 3 content is 1 wt%. The 1 wt% CeF 3 -coated LiNi 1/3 Co 1/3 Mn 1/3 O 2 can deliver a discharge capacity of 107.1 mA h g −1 even at 5 C rate, while the pristine does only 57.3 mA h g −1 . Compared to the pristine, the 1 wt% CeF 3 -coated LiNi 1/3 Co 1/3 Mn 1/3 O 2 exhibits the greatly enhanced capacity and cycling stability in the voltage range of 3.0–4.5 V, which suggests that the CeF 3 coating has the positive effect on the high-voltage application of LiNi 1/3 Co 1/3 Mn 1/3 O 2 . According to the analyses from electrochemical impedance spectra, enhanced electrochemical performance is mainly because the stable CeF 3 coating layer can prevent the HF-containing electrolyte from continuously attacking the LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode and retard the passivating layer growth on the cathode.

Adoption of a low water/powder (W/P) ratio is the key to improve the strength and durability of concrete, which relies on a high packing density because fresh concrete requires excess water to offer flowability. To obtain a high packing density, powders with different particle sizes, including limestone fines (LSF), superfine cement (SFC), condensed silica fume (CSF), were added to the cement paste and the resulting packing densities were measured directly by a newly-developed wet packing test. Results demonstrated that addition of powders with a finer size would more significantly improve the packing density but the powders should be at least as fine as 1/4 of the OPC to effectively improve the packing density. Packing density and voids ratio relationship showed that a small increase in packing density can significantly decrease the voids ratio, which could allow the W/P ratio to be reduced to improve the strength and durability of the concrete without compromising the flowability.

LiAlO 2 -coated Li 1.2 Ni 0.2 Mn 0.6 O 2 lithium-rich layered oxide was prepared and investigated as cathode material for lithium-ion batteries. X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) analyses revealed that a uniform LiAlO 2 layer was coated on the surface of Li 1.2 Ni 0.2 Mn 0.6 O 2 particles. The LiAlO 2 -coated Li 1.2 Ni 0.2 Mn 0.6 O 2 exhibited a great improvement on electrochemical performance, especially for its excellent cycling stability both at room and elevated temperature, compared to the pristine Li 1.2 Ni 0.2 Mn 0.6 O 2 . In addition, the LiAlO 2 -coated Li 1.2 Ni 0.2 Mn 0.6 O 2 showed obviously enhanced rate capability (162.6 mA h g −1 at 2 C and 112.3 mA h g −1 at 5 C) and suppressed the voltage fading during long-term and high-rate cycling. Based on these results, LiAlO 2 coating would be a promising method to improve the electrochemical performance of lithium-rich layered oxides.

Polarised light scattering experiments were conducted during the free drainage of SDS foams with three different bubble size distributions. Two types of completely polarised light were shone through the foam and all the five polarisation characteristic parameters (degree of polarisation P , degree of linear polarisation P L , degree of circular polarisation P C , orientation angle ψ and ellipticity angle χ ) of the scattered light were determined to examine the changes of polarisation state. During the drainage process, the bubble size distributions of the foams remained almost constant, but with a decreasing liquid fraction. This process can be divided into three stages based on the rate of the decrease in liquid fraction. This study was focused on the static stage where the rate of change in liquid fraction reduced to nearly zero. It was found that four of the polarisation parameters, P , P L , P C and χ exhibit sensitivities to the liquid fraction and the bubble size distribution. ψ is largely independent of the liquid fraction and bubble size distribution, but shows a certain degree of correlation with the structural rearrangement of the polydispersed foams.

We successfully demonstrated real-time 400G (64GBaud DP-16QAM) single-carrier ultra-efficient 1.2Tb/s superchannel (6.25bit/s/Hz) over new ultra-low loss large Aeff terrestrial fiber with long term error-free performance over 150km single-span and 250km (2 spans) using only EDFAs.

A bulk metallic glass (BMG), Zr 46 (Cu 4.5/5.5 Ag 1/5.5 ) 46 Al 8 (ZrCuAlAg), has been prepared and systematically evaluated in terms of microstructure, corrosion resistance, wear resistance, cytotoxicity, and in vivo implantation, aiming at exploring its use as a novel biomedical material. For comparison, the above-mentioned tests were also performed on Zr 51.9 Cu 23.3 Ni 10.5 Al 14.3 , Zr 51 Ti 5 Ni 10 Cu 25 Al 9 , and Ti 40 Zr 25 Ni 12 Cu 3 Be 20 BMGs, pure Ti and Ti–6Al–4V alloys. ZrCuAlAg BMG exhibits better corrosion resistance in both NaCl and Hank's solutions than other materials. The cell culture tests indicate that the BMGs exhibit a cytotoxicity of Grades 0–1, identical with pure Ti and Ti–6Al–4V alloys. Cell morphological analysis shows that the cells were flattened and well spread out on the surfaces of the BMGs, demonstrating their good cell compatibility. Animal tests proved that the ZrCuAlAg BMG implant performed as well as Ti–6Al–4V, without any obvious inflammation reaction at the implantation sites. The excellent biocompatibility of ZrCuAlAg BMG can be attributed to its amorphous structure-related high corrosion resistance as well as its unique composition, i.e. free of toxic Ni and Be, and containing biocompatible Ag element. It suggests that the Ag-bearing ZrCuAlAg BMG with excellent biocompatibility is promising for biomedical applications.

We have previously investigated foams with monodispersed bubbles using a polarised light scattering technique. The liquid fraction and the bubble size distribution were found to influence scattering properties of polarised light and correlate with the Mueller matrix elements. This paper focused on an investigation of the Mueller matrix of a bidispersed foam. Comparisons were made between the results of bidispersed foam and monodispersed foam.

In an aluminum reduction cell, crushed anode cover at room temperature is added onto the exposed bulk electrolyte surface around newly positioned anodes and is heated by high heat flux from this liquid electrolyte. Liquid electrolyte penetrates inside the porous anode cover. Solid cryolite and alumina crystallize from the liquid electrolyte due to the temperature gradient in the anode cover. A solidified crust forms at the bottom part of the anode cover during the heating up period. A thermochemical model which takes into account both the liquid electrolyte penetration and phase transformations has been developed to simulate the temperature evolution, chemical composition development, and liquid front penetration and content in the anode cover. The model is tested against experimental data obtained from industrial cells and laboratory experiments in this paper.

The spinel LiNi0.5−x Mn1.5+x O4 (x = 0, 0.05, 0.1) including LiNi0.5Mn1.5O4, LiNi0.45Mn1.55O4, and LiNi0.4Mn1.6O4 hollow microspheres has been prepared by adjusting the stoichiometric ratios of Ni and Mn with an impregnation method followed by a simple solid-state reaction. They are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, high-resolution transmission electron microscope, X-ray photoelectron spectroscopy, and electrochemical tests. The results show that LiNi0.5Mn1.5O4 is the ordered with the space group of P4332, but LiNi0.45Mn1.55O4 and LiNi0.4Mn1.6O4 are the disordered with the space group of Fd3m. All the three types of hollow microspheres have the similar primary particles. Compared to LiNi0.5Mn1.5O4, partial Ni atoms are substituted by Mn atoms in LiNi0.45Mn1.55O4 and LiNi0.4Mn1.6O4 lattices along with incorporation of small amounts of Mn3+. Although the ordered LiNi0.5Mn1.5O4 hollow microspheres deliver the highest capacity of 128.5 mAh/g at 1 C among the three types of spinel materials, the disordered LiNi0.45Mn1.55O4 hollow microspheres exhibit the highest capacity of 96.8 mAh/g at 10 C. The superior rate capability of LiNi0.45Mn1.55O4 hollow microspheres is attributed to the combination of the increased electronic conductivity and Li+-ion diffusion by moderate Mn3+ incorporation, along with the hierarchical structure.

A layered Li1.2Ni0.13Co0.13Mn0.54O2 cathode is coated with a CePO4 layer via a simple precipitation method. The pristine and CePO4-coated Li1.2Ni0.13Co0.13Mn0.54O2 are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscope (HR-TEM) and X-ray photoelectron spectroscopy (XPS), and the results indicate that CePO4 has been uniformly coated on the Li1.2Ni0.13Co0.13Mn0.54O2. Charge–discharge tests show that the CePO4-coated Li1.2Ni0.13Co0.13Mn0.54O2 has an obviously enhanced electrochemical performance compared with the pristine sample: the initial coulombic efficiency from 88.26% to 92.19%, rate capability from 6 to 110 mA h g−1 at 10 C, high-temperature performance from 59.5 to 219.6 mA h g−1 at 55 °C after 20 cycles, and low-temperature performance from 128.3 to 246.7 mA h g−1 at −20 °C. According to the analysis from dc impedance and electrochemical impedance spectra, the improvements on the electrochemical performance are mainly because the coated CePO4 layer can reduce side reactions of Li1.2Ni0.13Co0.13Mn0.54O2 with the electrolyte, and thus form the cathode–electrolyte interface (CEI) layer with enhanced Li+ diffusion. In addition, the CePO4 layer significantly improves the thermal stability of the coexisting systems of the charged cathode with the electrolyte. Therefore, CePO4 coating will be a promising approach to improve the electrochemical performance and thermal stability of Li-rich layered oxide cathode materials.

A polarised light scattering experimental set-up was designed to conduct experiments using Casein foams with monodispersed and bidispersed bubble size distributions. Foams were initially generated under forced drainage conditions to maintain a uniform axial liquid fraction profile. Subsequently, the foams entered a free drainage period. During this period, the liquid fraction, the bubble size distribution and the polarisation parameters of scattered light due to the foam were measured individually. It was found that both the liquid fraction and the bubble size distribution of Casein foams varied simultaneously with drainage time. Therefore, multiple regression analysis was performed to investigate the individual effect of these two foam factors on the polarisation state. Four of the polarisation parameters (degree of polarisation, degree of linear polarisation, degree of circular polarisation, ellipticity angle) were shown to be associated with the liquid fraction and/or the bubble size distribution to different extents. However, the remaining parameter, orientation angle, was completely independent of the liquid fraction and the bubble size distribution. These results can be used for the development of the polarised light scattering method in the study of protein foams.

Coating the Li-rich layered oxide cathode Li1.2Ni0.13Co0.13Mn0.54O2 with small amount of conductive carbon is realized by low-temperature sucrose carbonization in air. Carbon coating gives rise to a small amount of Mn3+ on the surface of the Li1.2Ni0.13Co0.13Mn0.54O2. The 1.2 wt% carbon-coated Li1.2Ni0.13Co0.13Mn0.54O2 shows obviously enhanced electrochemical performances, especially in improving rate capability and suppressing the voltage fading during long-term and high-rate cycling. According to the analysis from cyclic voltammetry (CV) and electrochemical impedance spectra (EIS), the improvements on the electrochemical performances are mainly because the coated carbon layer can function by not only increasing the electronic conductivity at the interface with electrolyte but also improving bulk electronic and ionic conductivity by small amounts of Mn3+. Therefore, carbon coating is a promising approach to improve the cyclic stability of the Li-rich layered oxides.

The constitutive relationship between stress and strain is one of the important issues in numerical simulation of metal forming. For steel, there are two kinds of constitutive models wildly used. One is power law like Ludwik and Swift. The other is saturation models like Voce and Hockett-Sherby. It is necessary to determine the most appropriate model and parameters for newly developed high strength steels. In order to describe the ultra-high strength dual phase and quenching and partitioning steels, uniaxial tensile tests with the aid of digital image correlation techniques were performed to analyse the strain field over the whole gauge section as well as the element close to the necking point. Through experimental data analysis and numerical fitting, the validity of different models have been confirmed. It shows that equation of Hockett-Sherby model has the best fitting accuracy and high strength steels require a model with more parameters. The extrapolated weighting coefficient of combined Swift and Hockett-Sherby models is characterized, which is proved to improve the accuracy of the numerical simulation of forming of ultra-high strength steels based on the conventional tensile tests.

Experiments were conducted using well-controlled bubble size-distributed foam stabilised by Sodium Dodecyl Sulphate (SDS) solution to investigate the individual effect of liquid fraction of foam on the six independent normalised Mueller matrix elements via polarised light scattering technique. The liquid fraction, bubble size distribution and the Mueller matrix elements were measured individually during a foam free drainage process. It was found that the effect of foam properties on the Mueller matrix was more obvious when the foam was in a static state. Under the circumstance that the bubble size distribution was kept almost constant during the drainage process, the six independent normalised Mueller matrix elements showed dependence on the liquid fraction except N 34 , whereas N 22 and N 33 showed the highest sensitivity. In addition, N 12 and N 44 exhibited reflection symmetry in the static stage during foam draining. This suggests that only five independent Mueller matrix elements are sufficient to represent the current foam because of its axisymmetry.

The glass substrates containing metal Ag nanoparticles (NPs) were fabricated by electric field assisted ion diffusion process. Two luminescent substances, NaYF4:Er3+/Yb3+ and CdSe, were deposited on the substrates respectively, and their luminescent properties were studied. The results showed that compared with Ag NPs coated on the surface of the substrates, the stability of Ag NPs was significantly enhanced and also that Ag NPs embedded in the substrates produced higher luminescent enhancement for different fluorescent substances. Seven- and threefold fluorescence enhancements were achieved for up-conversion luminescence of Er3+/Yb3+ codoped NaYF4 and down-conversion luminescence of CdSe quantum dots (QDs) respectively. Moreover, it was indicated that introduction of Ag NPs into glass substrate by electric field assisted ion diffusion process improved sensitivity of CdSe QDs for Cu2+ detection. Therefore, the electric field assisted ion diffusion process would be a promising method for the fabric...

Supercritical fluid methods offer an alternative to conventional mixing methods, particularly for heat sensitive drugs and where an organic solvent is undesirable.To design, develop and construct a unit for the particles from a gas-saturated suspension/solution (PGSS) method and form endogenous progesterone (PGN) dispersion systems using SC-CO2.The PGN dispersions were manufactured using three selected excipients: polyethylene glycol (PEG) 400/4000 (50:50), Gelucire 44/14 and D-α-tocopheryl PEG 1000 succinate (TPGS). Semisolid dispersions of PGN prepared by PGSS method were compared to the conventional methods; comelting (CM), cosolvent (CS) and physical mixing (PM). The dispersion systems made were characterized by Raman and Fourier transform infrared (FTIR) spectroscopies, X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), PGN recovery, uniformity and in vitro dissolution, analyzed by high-performance liquid chromatography (HPLC).Raman spectra revealed no changes in the crystalline structure of PGN treated with SC-CO2 compared to that of untreated PGN. XRPD and FTIR showed the presence of peaks and bands for PGN confirming that PGN has been incorporated well with each individual excipient. All PGN dispersions prepared by the PGSS method resulted in the improvement of PGN dissolution rates compared to that prepared by the conventional methods and untreated PGN after 60 min (p value0.05).The novel PGN dispersions prepared by the PGSS method offer the great potential to enhance PGN dissolution rate, reduce preparation time and form stable crystalline dispersion systems over those prepared by conventional methods.

The aim of this study was to determine the effect of supercritical carbon dioxide (SC-CO2) on the crystallinity and drug release of Gelucire 44/14-based endogenous progesterone (PGN) dispersion systems. The light scattering from PGN crystals incorporated in Gelucire 44/14 was imaged using optical microscopy. In vitro dissolution was used to determine the release kinetics of PGN, Gelucire 44/14, incorporated by a supercritical fluid (SCF) method. Release profiles were evaluated according to zero-order, first-order, Higuchi, Krosmeyer-Peppas, and dual first-order models. The dual first-order release model illustrated two distinct release rates: an initial rapid release followed by a slow diffusion of PGN from the dispersion systems. The dual first-order release model adds a new tool to the elucidation of release mechanisms from lipid and micelle-forming-based dispersion systems, where parallel processes contribute to drug release.

This paper reports the characterization of scandium aluminum nitride (Al1−x Sc x N, x = 27%) films and discusses surface acoustic wave (SAW) devices based on them. Both AlScN and AlN films were deposited on silicon by sputtering and possessed columnar microstructures with (0 0 0 2) crystal orientation. The AlScN/Si SAW devices showed improved electromechanical coupling coefficients (K 2, ~2%) compared with pure AlN films (

When the anode cover is heated up in the reduction cell, the crust formation from the anode cover commences at the bottom and the process is driven by thermo-chemical processes. It is important to study the composition and thermal stability properties of the crust in order to understand the mechanisms of crust formation and deterioration. Several crust pieces were taken from industrial prebaked anode cells. A number of vertical crust sections were sampled from these pieces, and each section was analyzed for composition and phase change temperature. Results show that the bottom layer is enriched in cryolite, consistent with results published in the literature. The upper region was found to contain more chiolite. Crushed bath-based anode crust has higher CR than alumina based anode crust. The melting of chiolite in the crust leaves substantial macro-porosity there, which contributes to the absorption of NaAlF4 and the penetration of bath through it. The formation conditions of crystalline crust were discussed.

Analysis and discussion are presented for the various schemes that may be used in evaluating results such as the current efficiency (CE) obtained from aluminum smelting cell performance trials. A conventional parametric (requiring normal distribution of data) and a nonparametric (not requiring normal distribution) statistical method are given. The analysis allows the results obtained to be expressed in statistical terms with a known level of significance, thus providing a more scientific basis for the interpretation of the results. A scheme for experimental design that takes into account inherent variations and the use of a nonparametric statistical test which does not stipulate normal distribution of data are both suggested.

Temperature in a continuous steel annealing furnace is studied using a 3D finite element model with minimal simplification of the furnace design and heat transfer physics. This allows investigation of the temperature distribution of the furnace and steel strip and provides understanding of important operational factors such as increased heating of the strip edges and cooling of thermocouple probes due to radiative heat transfer. This information enables the use of simpler models in production situations and can help optimize furnace operating methods and improve product quality.

A dual resonant converter with two transformers is presented in this paper. Dual resonant tanks are composed of leakage inductors and resonant capacitors to achieve zero-current-switching turnoff for rectifier diodes at the secondary side of the transformer. Hence, the reverse-recovery problem of the rectifier diodes can be eliminated. Moreover, the active-clamp circuit does not only absorb the energy stored in the leakage inductor but also clamp the voltage stress of power switches. Compared to the conventional dual resonant converter, the zero-voltage switching operation of the proposed converter is easily achieved by using two transformers. The operation principles, design considerations, and realization are discussed in detail. Finally, experimental results from a 400-W laboratory prototype are presented to confirm the effectiveness of the proposed converter.

Laboratory scale electrolysis experiments were conducted to investigate the electrowinning of aluminium using hydrogen diffusion anodes. A potassium-based electrolyte (KF–AlF 3 –Al 2 O 3 ), porous nickel alloy anode and molybdenum disk cathode were used in experiments at 750 °C. Hydrogen gas was supplied to the anode/electrolyte interface through the porous anode. Experiments were conducted in potentiostatic, galvanostatic and galvanodynamic modes. There was a measurable depolarisation of the anode potential and also anode reaction of hydrogen and oxygen ions in the bath to form water vapour was confirmed by the water vapour condensate found at the electrolysis exit gas pipe. Metallic aluminium was found on the spent cathode. The experiments conducted in the galvanodynamic mode suggested that the rate limiter for hydrogen oxidation was the availability of surface hydrogen at the anode/electrolyte interface. The anode surface corroded during electrolysis and impurities were found both in the molten bath and on the cathode.

A high power and efficiency of c-cut Tm, Ho:YAlO3 (YAP) laser is reported in the paper. The laser operated in continuous wave (CW) mode or Acousto-optical (AO) Q-switched mode at 2044 nm. The Tm, Ho:YAP crystal was cooled at the temperature of 77 K and pumped by a fiber-coupled laser diode (LD) with the centre output wavelength of 794.8 nm. In CW operation, a 9.30-W output power was obtained at a 150-mm physical cavity length, corresponding to a slope efficiency of 42.5%. In Q-switch mode, the output average power of 9 W was achieved at the pulse repetition frequency (PRF) of 10 kHz with a 130-ns pulse width. Moreover, the energy per pulse of 3.54 mJ in 47 ns was acquired at 2.5 kHz with a 75.3-kW peak power.

Temperature in a continuous annealing furnace is studied by furnace modelling using two methods. A 3D model is used to investigate the temperature distribution of the steel strip that is being annealed and the furnace thermocouple probes, and information from the 3D model enables the construction of a highly simplified 1D/2D model, which predicts furnace and strip temperatures with very good agreement to the 3D model. The simple model has a very short solution time and is suitable for rapid simulation of alternative furnace operating conditions in order to optimise heat treatment quality, plant throughput and energy consumption.

Compressive deformation behaviors of a cast Ti40Zr25Ni3Cu12Be20 bulk metallic glass in the test temperatures ranging from 428 to 658 K were examined in a broad range of strain rates from 1.3 × 10−4 to 3 × 10−2 s−1. The alloy studied exhibits an extraordinary compressive superplastic formability within the supercooled liquid region, typically evidenced by a large compressive strain up to 0.83. The superplastic flow behaviors are strongly dependent on the test temperatures and applied strain rates. At low temperatures or high strain rates, the viscosity measured is found to dramatically decrease with increasing strain rate (i.e., non-Newtonian flow) and a stress overshoot is detected in the first steps of strain. At low strain rates or high test temperatures, the studied glass exhibits a Newtonian flow behavior. The value of activation volume increases with increasing test temperatures.

Nanoscratch experiments on four bulk metallic glasses using a pyramidal diamond tip (Berkovich) indenter have been carried out under different loads and scratching velocities. There exists a general correlation between the hardness and wear resistance, i.e., a lower hardness produces a lower wear resistance. Scratch velocity appears to have little effect on the scratch depths of the four alloys studied. However, faster scratch velocity leads to finer shear bands. Compared with ribbon sample with the same chemical composition, Ti-based bulk glassy sample that experienced slower cooling rate during solidification, and thus contained less free volume, exhibits better wear resistance.

A ZK60 alloy was processed by two-step equal channel angular pressing (ECAP) in order to refine the grain size and enhance the mechanical properties. The results show that fine grain size less than 1 μm was obtained after the two-step ECAP process, 4 passes at 513 K, followed by another 4 passes at 453 K. The strength of ZK60 alloy decreased after the single-step ECAP process but recovered after two-step ECAP process. The strength decrease was related to the texture softening. Compared with the single-step ECAP at 513 K, the two-step ECAP has significantly improved the yield strength and ultimate tensile strength of the alloy. The mechanism of the notable grain refinement of the ECAP process was mainly attributed to continuous dynamic recovery and recrystallization.

Based on the semi-self-consistent field (semi-SCF) d-orbital theory and point charge model, we have studied the optical spectra by the complete diagonalizing (of energy matrix) method (CDM) and electronic paramagnetic resonance (EPR) spectra by the perturbation theory method (PTM) for Ni2+ center in the ammonium nickel(II) sulfate hexahydrate [(NH4)2Ni(SO4)·6H2O, abbr. ANSH] crystal. The structural parameters of the ANSH crystal have been obtained and theoretical results agree well with the experimental findings.

In this paper, we successfully developed a novel method to synthesize uniform carnation-like lithium vanadate nanostructures by combining electrochemical deposition and solvo-hydrothermal method. The samples were characterized by field emission scanning electron microscopy, power X-ray diffraction, and thermogravimetric analysis. The results show that the LiV3O8·H2O carnation-like nanostructure is 2–3 μm in diameter and assembled from nanosheets with thickness of 10–20 nm. Based on a series of experiments, we proposed a possible growth mechanism, in which the supersaturation derived from electric field and high conductivity under solvo-hydrothermal conditions due to the successive growth of lithium vanadate. In our work, we have discussed three different solvo-hydrothermal systems. It is proved that the morphology of coating materials could be conveniently controlled by selecting alcohols with different chain of alkyl. Compared with short-chain alcohol, CH3–(CH2)6–CH2–OH was beneficial to promote the oriented growth of nanosheets. Electrochemical performances of lithium vanadate cathode materials were characterized by galvanostatic charge–discharge, and LiV3O8 synthesized in n-octanol aqueous solution exhibits the highest capacity of 357 mAh g−1 and best cycle stability. Furthermore, the influence of solvo-hydrothermal conditions on the morphology and electrochemical performance of products has also been studied.

The mechanical properties of Ti-based metallic glasses prepared with different cooling rates have been carried out using nanoindentation at different loading rates. The effect of applied loading rate and sample size on the deformation was studied. It is found that lower loading rate promotes serrations or pop-in events. The gradual disappearance of pop-in events observed on load–displacement (P–h) curves represents a transition from discrete shear band activity at low loading rates to the simultaneous operation of multiple shear bands at higher loading rates. The pop-in size was observed to be load or contact depth dependent. An obvious creep displacement, sensitive to loading rates, was observed during the holding period at the maximum load. The cooling rate employed in sample preparation significantly influences the nano-mechanical properties of the metallic glasses, in that the ribbon sample exhibits lower hardness, incipient plasticity at lower applied load and greater pile-up height than bulk samples.

X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and differential scanning calorimetry (DSC) were performed to investigate the critical cooling rate and thermal stability of Ti40Zr25Ni3Cu12Be20 metallic glass. The critical cooling rate for glass formation of the studied metallic glass is determined to be as low as 3.2 K/s, revealing a high glass-forming ability. The activation energies of the alloy are strongly dependent on the cooling rate during rapid solidification. Compared with the ribbon sample, the bulk sample that experiences slower cooling rate during solidification contains a greater degree of medium range orders (MRO), which favors nucleation, therefore leading to its smaller activation energies.

In this study, the room temperature creep behavior of Fe 41 Co 7 Cr 15 Mo 14 C 15 B 6 Y 2 bulk metallic glass wasinvestigated using nanoindentation technique with the maximum applied load ranging from 1 mN to100 mN under different loading rates (0.01–2.5 mNs 1 ). The creep stress exponent was derived from therecorded displacement–holding time curve. It was found that the stress exponent increases rapidly from2.87 to 6.37 with increasing indentation size, i.e. exhibiting a positive indentation size dependence.Furthermore, as the indentation loading rate increases from 0.01 mNs 1 to 2.5 mNs 1 , the stressexponent decreases gradually from 4.93 to 0.94. The deformation mechanism causing the nano-indentation creep is discussed in the light of the ‘‘shear transformation zone’’ (STZ) which providesqualitative explanation for the observed plasticity in amorphous alloy. 2008 Elsevier Ltd. All rights reserved. 1. IntroductionThe last twodecades havewitnessed rapid development of bulkmetallic glasses (BMGs), which exhibit some unique mechanicalproperties and high potentiality for application as advancedstructural and functional materials [1–3]. While extensive plasticstrain can be reached in few localized shear bands, BMGs usuallyexhibit little or no macroscopic plasticity at room temperature[2–4]. Recently, several researchers have studied the plastic defor-mation mechanisms of BMGs using nanoindentation (see forexample Refs. [5,6]). Study of time-dependent deformation (i.e.creep) of metallic glasses using nanoindentation has been rare[7–9]. Apart from its scientific interest [10], creep under sub-micrometercontact is an issue of practical engineering significancefor the applications of MEMS and NEMS. From the indentationcreep studies of crystalline materials, a few indentation creepmethods have been proposed and used [11]. The constant loadholding method is the most widely used one, where the indentertip is maintained at a prescribed load, for an extended time period,while the displacement of the indenter into the surface iscontinuouslyrecorded,akintotheconstantloadcompressioncreeptests [11–13].The purpose of the present work is to investigate the creepbehaviors of an Fe-based bulk metallic glass. The stress exponentvalues were derived fromthe displacement–holding time curves. Itwas found that the stress exponent values obtained are dependenton the applied peak loads and indentation loading rates. Thedeformation mechanisms of metallic glasses are discussed.2. Experimental procedureAlloy ingots with nominal composition of Fe

In this work, the time-dependent plastic deformation behavior of Ti40Zr25Ni3Cu12Be20bulk and ribbon metallic glass alloys was investigated using a nanoindentation technique at room temperature with the applied load ranging from 5 to 100 mN. The stress exponentn, defined as, has been derived as a measure of the creep resistance. It was found that the measured stress exponent increases rapidly with increasing indentation size, exhibiting a positive size effect. The size effect on the stress exponentnobtained from the bulk sample is more pronounced than that obtained from the ribbon sample. The deformation mechanism involved will be discussed.

The purpose of this study was to design and build a supercritical CO(2) anti-solvent (SAS) unit and use it to produce microparticles of the class II drug carbamazepine. The operation conditions of the constructed unit affected the carbamazepine yield. Optimal conditions were: organic solution flow rate of 0.15 mL/min, CO(2) flow rate of 7.5 mL/min, pressure of 4,200 psi, over 3,000 s and at 33 degrees C. The drug solid-state characteristics, morphology and size distribution were examined before and after processing using X-ray powder diffraction and differential scanning calorimetry, scanning electron microscopy and laser diffraction particle size analysis, respectively. The in vitro dissolution of the treated particles was investigated and compared to that of untreated particles. Results revealed a change in the crystalline structure of carbamazepine with different polymorphs co-existing under various operation conditions. Scanning electron micrographs showed a change in the crystalline habit from the prismatic into bundled whiskers, fibers and filaments. The volume weighted diameter was reduced from 209 to 29 mum. Furthermore, the SAS CO(2) process yielded particles with significantly improved in vitro dissolution. Further research is needed to optimize the operation conditions of the self-built unit to maximize the production yield and produce a uniform polymorphic form of carbamazepine.

In this paper, we report a mathematical model that incorporates the solution of the detailed concentration profile in a hollow-fibre ultrafiltration membrane system using Dextran and Polyvinylpyrrolidone (PVP) as model fluids. Initial experiments on such a system were performed by Clifton et al.[I] in the mid 1980s, and modelled using an approximate function of concentration distribution. This model has since been adopted by many other researchers for simulating systems that are similar in nature. However, this model does not predict very well the pressure drop across the entire fibre length. We have shown, with the incorporation of a more realistic account of mass transfer, that the present model can give good agreements with the experimental results, not only for permeate flux along the fibre but also for the outlet pressures.

The challenges in developing a fault detection and diagnosis system for industrial applications are not inconsiderable, particularly complex materials processing operations such as aluminium smelting. However, the organizing into groups of the various fault detection and diagnostic systems of the aluminium smelting process can assist in the identification of the key elements of an effective monitoring system. This paper reviews aluminium process fault detection and diagnosis systems and proposes a taxonomy that includes four key elements: knowledge, techniques, usage frequency, and results presentation. Each element is explained together with examples of existing systems. A fault detection and diagnosis system developed based on the proposed taxonomy is demonstrated using aluminium smelting data. A potential new strategy for improving fault diagnosis is discussed based on the ability of the new technology, augmented reality, to augment operators’ view of an industrial plant, so that it permits a situation-oriented action in real working environments.

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

Heat transfer is an unsteady process in the initial period of ice nucleation or phase transition from aqueous solution. During this period the latent heat of freezing increases the temperature in bulk solution monotonously until the system reaches equilibrium. Meanwhile heat can transfer from the solution to the environment or vise versa. The analysis of this unsteady heat transfer process leads to the establishment of a mathematical model, which is represented by two simultaneous differential equations. Using the Laplace transform and inverse transform, and incorporating the initial condition of ice nucleation, we obtained an analytical solution of this model. Further discussion of the model’s fitness by comparing to the experimental data leads to a recognition that ice fouling (or ice adhesion) on the cooler wall should be highlighted in estimating the heat transfer resistance at the very beginning of the ice formation. The model fits to the experimental data satisfactorily.

This paper proposes a method of a symmetric optothermal microactuator (S-OTMA) directly driven by laser pulse. Based on the principle of thermal flux, a dynamic model is established describing the laser-induced optothermal temperature rise and optothermal expansion of the S-OTMA's expansion arm. The dynamic optothermal expansion and the relationship between the expansion amplitude and laser pulse frequency are simulated, indicating that the expansion arm expands and reverts periodically with the same frequency of the laser pulse, and that the expansion amplitude decreases with the increase of laser pulse frequency. Experiments have been further conducted on a micro-fabricated S-OTMA under a laser pulse of 3.3 mW power and 2–18 Hz frequency. It is shown that the S-OTMA can periodically deflect in accordance with the same frequency of the laser pulse, with a maximum response frequency of at least 18 Hz. The maximum deflection (vibration) amplitude is measured to be 13.7 µm (at 2 Hz), and the amplitude decreases as the frequency increases. Both the theoretical model and experiments prove that the S-OTMA is capable of implementing direct laser-controlled microactuation in which only ~3 mW laser power is demanded. Furthermore, bi-directional actuation of the optothermal microactuator (such as S-OTMA) can be easily achieved by alternately irradiating either arm of the microactuator. This work may broaden the applications of the S-OTMA, as well as optothermal microactuators in MEMS/MOEMS and micro/nano-technology.