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Multi-task learning (MTL) is a machine learning method to share knowledge for multiple related machine learning tasks via learning those tasks jointly. It has been shown to be capable of effectively improving the generalization capability of each single task (learning just one task at a time). In this paper, we propose a novel MTL architecture that first combines 3D convolutional neural networks (3D CNN) plus the long short-term memory (LSTM) networks together with the MTL mechanism, tailored to information sharing of video inputs. We split each video into several clips and apply the hybrid deep model of 3D CNN and LSTM to extract the sequential features of those video clips. Therefore, our MTL model can share visual knowledge based on those video-clip features among different categories more efficiently. We evaluate our method on three popular public action recognition video datasets. The experimental results show that our novel MTL method can efficiently share detailed information in video clips among multiple action categories and outperforms other multi-task methods.

The Aurivillius-type Bi2VO5.5-δ series doped by magnetic cations may have a significant electronic contribution to their total conductivity and special magnetoelectric properties which extend potential applications to magnetoelectronic and spintronic fields. Bi2(V1-xMnx)O5.5-δ and (Bi2-xMnx)VO5.5-δ (x = 0.10–0.30) compounds with nominal composition doped by manganese cation on the Bi- or V-site were prepared via a solid-state reaction. Results show that partial substitution of Mn on the V-site stabilizes Bi2(V1-xMnx)O5.5-δ in the high-temperature tetragonal structure of Bi2VO5.5-δ for compositions in the range 0.10 ≤ x

Nano-porous SiO2 insulation material was made from foamed aqueous slurry of nano-silica powder by filter-pressing. The foamed aqueous slurry mainly consists of hydrophobic SiO2 nano-particles, xonotlite whiskers and glass fiber. The latter two will enhance strength of the insulation material. Rheological properties of the foamed slurry with varying solid mass concentration were studied. The effect of forming pressure on the density and pore size distribution of the nano-porous silica material was investigated. It was found that the foamed slurry with solid concentration less than 17% behaves pseudoplastic as decreasing its apparent viscosity with increasing of shear rate during rheological testing. Homogeneous foamed slurry can be obtained when solid concentration in it is below 7%. Such slurry should be dewatered into solid concentration being of 10-15% before filter-pressing. Rigorously stirring of the concentrated slurry is required before pouring it into a mould, which leads to reducing the viscosity of the slurry and helps uniformly filling mould. During pressing the loading speed should be strictly controlled in order to reaching designed pore size distribution in SiO2 insulation material. The SiO2 insulation material with apparent density about 0.45g/cm3 and pore size mainly ranging from 10 to 50nm was obtained.

Porous Si3N4/SiO2/BN composite ceramics with high strength and low dielectric constant were prepared by dry-pressing process and pressureless sintering at 1750°C for 1.5 h in flow nitrogen. The influences of BN content on microstructure, porosity, mechanical and dielectric properties of the porous Si3N4/SiO2/BN composite ceramics were discussed. The results showed that the porous Si3N4/SiO2/BN composite ceramics with porosity ranging from 29% to 48% were fabricated by adjusting the content of BN. The flexural strength of the porous Si3N4/SiO2/BN composite ceramics was 78215 MPa. The dielectric constant of the porous Si3N4/SiO2/BN composite ceramics was 3.9~5 at 1 MHz.

Porous SiO2 insulation material was made by wet process. Fibrous xonotlite crystal and glass fiber were used as reinforced fibers, and graphite, zirconia and titania powders were added as infrared scattering materials into the porous SiO2 insulation material. The density of the SiO2 insulation material was about 0.3g/cm3. The porosity was about 85%, and the pore size was mainly ranged from 20 to 60 nm in diameter. Heat transfer due to solid conduction and gas convection was reduced greatly because of the existence of larger amount of nano pores. Thermal radiation was partly blocked by the infrared scattering powders. Thermal conductivity of the porous SiO2 insulation material added with graphite powder as infrared scattering powder can reach as low as 0.04W/m.K at 700°C. The type and amount of added infrared scattering powders had important influence on the thermal performances of insulation materials.

BiFeO3-based single-phase multiferroics have been widely studied in both ceramics and films. However, the macroscopic magnetic properties of BiFeO3 ceramics were now most very weak. In this work, MnO2 and Co2O3 were used as B-site substitutes in BiFeO3 ceramics in order to the enhancement of magnetic properties. The change of magnetization was analyzed based on the phase composition and the microstructure of ceramics.

Two types of water-insoluble protein from Bombyx mori silkworm, degummed and undegummed superfine silk powders, were prepared through a physical method. Water-soluble superfine silk fibroin powder was obtained from salt-dissolved, dialyzed and freeze-dried silk fibroin. These three types of superfine silk powders were blended with solution of commercially available biomedical grade segmented polyurethane (PU) to prepare elastic biofiber by a wet-spinning process. The objective of the current study was to identify the feasibility of wet spinning of polyurethane/superfine silk powder blend elastic biofiber, and analyse and compare the mechanical properties of the as-spun biofibers. Superfine silk fibroin powders and PU were dispersed in dimethyl formamide (DMF) and the dope solution exhibited good fiber formation in a warm distilled water coagulation bath. The superfine silk powder/PU blend fiber had a smooth surface, dense structure, and considerably high strength with a circular cross-section. The future further investigation will be carried out to analyse in detail the structure and morphology of the as-spun fiber. The silk-inspired biomedical polyurethane biofiber showed potential as a biomaterial for small-diameter artificial vascular scaffolds.

Extrusion gelation freeform fabrication (EGFF) is a new solid freeform fabrication technique to fabricate ceramic parts. The study of ceramic suspensions rheological behavior is essential to a better understanding of parts fabrication through EGFF process. In this paper, the effects of dispersant concentrations, solids loading and binder composition on the rheological behavior of alumina suspensions were examined. The optimal amount of dispersant was found to be about 0.1 wt.%. The suspensions with 50 vol.% alumina and 1wt.% sodium alginate show shear thickening behavior. Such behavior is unfavorable for extrusion gelation freeform fabrication. By addition of PVA or styrene-acrylic latex, the rheological behavior of suspensions was changed. The addition of PVA or latex has a great effect on the viscosity of the suspensions and the type of their rheological behavior. The ceramic suspensions with PVA or latex were found to be shear thinning more suitable for EGFF.

As a good binder for aqueous Al2O3 suspensions tape-casting process, a commercial styrene-acrylic latex binder had been investigated. This paper studied on the rheological behaviors of the suspensions and drying process of aqueous slurries with latex binder system, and the research results indicated the rheological behaviors was affected by pH value, solid loading and dispersant (PAA-NH4) additives; and the drying speed of slurries was most decided by drying temperature and slurry coating thickness.

Piezoelectricity of composite was simulated by employing Dilute Model and Limit Unit method. The analogizing results recommend that the particle stackers influence the properties of piezo-composite. While fabricating piezo-composite, particles stack different with different routine. For thermo-pressing proceeding, stackers trend to take on higher D33 than that processing from forging-membrane.

This paper focuses on the structural change and the thermochromism of the phase transition of the hybrid (C12H25NH3)2FeCl4. The temperature and the structures of the phase transition is investigated by a thermal gravimetry (TG) and differential scanning calorimetry (DSC), an infrared spectra (IR) and X-ray diffraction (XRD) patterns. The UV adsorption spectra account for the thermochromism. The results suggest that the reversible phase transition arises from the structural changes of the organic chains. The thermochromism is presumably due to the electrons redistribution on the levels and to the energy transition to translational and rotational motions of the organic chains.

This paper focuses on the influence of interactions between different species in hybrids (CnH2n+1NH3)2MCl4 (M = Mn, Cu; n =2,4,6,8,10) on the structural stabilities. DSC-TG curves were used to find out the onset and the end decomposition temperatures. The results show that the hybrids of M =Cu start to decompose at about 210 centigrade degrees, average 25 centigrade degrees lower than that of M=Mn. The end temperatures of M=Cu are also lower. This suggests that in this case the thermal stabilities of the hybrids would be governed by the interactions between the organic and inorganic species and are little affected by weak Van de Waals interactions between the organic and organic species.

A new method, which allowed lamination at room temperature without any additional adhesive, was described in this paper. A low Tg styrene-acrylic latex binder was used to forming the green tape via a water-based slurry. The green tapes could adhere to each other at room temperature under low or slight pressure. The density and deformation of laminated green parts depended significantly on lamination pressure, but the density of green parts did not increase after the lamination pressure exceeded a specific value of 4MPa. The interface between the tapes had been investigated in the green and sintered state by SEM. The experimental results showed that the microstructure of interface and density of lamination ceramics was a function of fraction of binder, plasticizer, and laminated pressure.

Polyurethane was blended with silk fibroin and heparin to prepare a heparin-releasing system. The release rate and the percentage of the cumulative amount of the released heparin can be controlled by the loading amount of heparin in the film, the composition ratio of silk fibroin to polyurethane, and the thickness of the film. The slower and more sustained release of heparin can be obtained by increasing the film thickness, the loading amount of heparin and the content of silk fibroin in the film. Thus the high bioactivity and long lasting antithrombogenicity of the raw heparin can be maintained for the blended film. The coagulation time tests showed that the composite film had good blood compatibility.

Extrusion gelation freeform fabrication process is an extrusion-based freeforming technique capable of fabricating complex shaped monolithic ceramic prototypes by the sequential deposition and solidification of ceramic suspensions from a computer aided design model. In this process, ceramic parts are produced using an extrusion nozzle suitable for extruding ceramic suspensions. In this study, the processing parameters influencing on manufacturing Al2O3 parts were discussed. Air pressure on top of suspensions, rotating speed of screw, nozzle diameter and scan speed are the main factors to influence the dimensional precision of ceramic bodies. By optimizing these processing parameters, the green bodies were fabricated with high precision. The sintered samples with homogenous microstructure and ~97.6% relative density could be prepared by sintering of these green bodies at 1600oC for 2 hours.

By means of a finite element method model, the effects of property parameters of refractory on thermal stress of injection lance have been studied. The results show that the maximum thermal stress increases with the improvement of thermal conductivity and elastic modulus of refractory, while it decreases at first and then increases with the improvement of the coefficient of expansion of refractory.

p-nitrophenol is synthesized using p-nitrochlorobenzene and sodium hydroxide with phase transfer catalyst. Several reaction factors, such as catalyst type, the amounts of catalysts and sodium hydroxide, the concentration of sodium hydroxide solution as well as reaction time, affect greatly the yield of p-nitrophenol. The optimum reaction conditions are as follows: A-1 used as phase transfer catalyst whose consumption is 6% (mole fraction) of p-nitrochlorobenzene; the molar ratio of sodium hydroxide to p-nitrochlorobenzene is 3:1; the concentration of sodium hydroxide solution is 50% (mass fraction). Nitrobenzene, whose molar amount is 2.45 times as much as that of p-nitrochlorobenzene; reaction time is 7 h at 140 °C under normal pressure. The final yield of p-nitrophenol is 83.6%.