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• ChS-Cur polymeric micelles were prepared by radical polymerization. • The micelles showed a good dispersion stability as its high negative zeta potential. • In vitro cytotoxicity tests showed that the ChS-Cur micelles were non-cytotoxic. • The micelles micelles had redox sensitivity for drug release at tumor sites. Chondroitin sulfate-curcumin (ChS-Cur) polymeric micelles derived from oxidized Chondroitin sulfate (ChS), Curcumin (Cur) and Bis-acrylamide cysteine (BAC) were prepared by radical polymerization. The morphology, Zeta potential, cytotoxic and drug release behavior were explored. ChS-Cur polymeric micelles hold a spherical structure with a particle size of about 250 nm, and micelles showed a good dispersion stability. Release studies showed that the controlled release profile of drug was obtained and the micelles had redox sensitivity. In vitro cytotoxicity studies showed that the ChS-Cur micelles were non-cytotoxic. [ABSTRACT FROM AUTHOR]

Abstract: Ni–SiC metal matrix composites with two kinds of SiC content were prepared by electroforming in a nickel sulphamate bath. Tensile strength and microstructure of the composites before and after heat treatment were investigated. The maximum of tensile strength was obtained after heat treatment at 300 °C×24 h. The values were 641 N/mm2 and 701 N/mm2 respectively. The complete reaction between nickel and SiC particles can produce shrinkage pores in the interface. The volume of shrinkage pores was equal to 8% of the volume of SiC particles in the composites. The interfacial reaction products were composed of Ni3Si and a little amount of Ni31Si12 after heat treatment at 600 °C×24 h. The fracture evolution went though microcracks initiation, growth and coalescence. Cracking of the matrix, debonding of Ni–SiC interfaces and cracking of particles were three types of cracking modes for Ni–SiC composites. [Copyright &y& Elsevier]

• Constraint tensile stress increased the α-Fe transformation start temperature of HAZs. • Constraint tensile stress increased the volume fraction and average size of Cu-rich particles in HAZs. • The increment of α-Fe transformation start temperature promoted the precipitation of Cu-rich particles in α-Fe matrix. • The tensile strength of FGHAZ increased from 970 MPa to 1032 MPa due to the nanoscale Cu-rich precipitation strengthening. The effect of welding constraint on nanoscale Cu-rich precipitation in welding heat affected zones (HAZs) of Cu-bearing steel was studied in this work. Due to the constraint tensile stress of 150 MPa, α-Fe transformation start temperature (T s) of CGHAZ and FGHAZ increased by 55 °C and 42 °C, respectively. The volume fraction and average size of 9R-structural Cu-rich particles in FGHAZ increased from 0.3 % to 0.8 % and from 5 nm to 8 nm, respectively. Three-dimensional phase field simulation shows that the increment of T s promoted the precipitation of Cu-rich particles in α-Fe matrix. However, the T s of restrained CGHAZ was too low to favor the precipitation of Cu-rich particles. The tensile strength of FGHAZ increased from 970 MPa to 1032 MPa due to the nanoscale Cu-rich precipitation strengthening. [ABSTRACT FROM AUTHOR]

• Interactive heat treatment was used to fabricate functionally graded materials. • Fine Nb-rich carbides generated around the semi-dissolved Laves phases. • Stacking faults and dislocation tangles were induced by Nb-rich carbides. • Tensile strength was improve from 512 ± 15 MPa to 602 ± 10 MPa. In-situ heat treatment (IHT) was introduced in wire arc additive manufacturing (WAAM) process to fabricated Inconel625-high strength low alloy (HSLA) steel functionally graded material (FGM). The graded region with severe Laves phases precipitation was heat treated in 1080℃/1h and 1080℃/2h to alleviate the Laves phases adverse effects. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscope (TEM) were applied to analyze the microstructures of the FGMs. By using IHT, the Laves phases were dissolved, Nb-rich carbides packed with dislocation tangles and stacking faults generated, and the tensile strength along the building direction of the Inconel625-HSLA steel FGM has been improved from 512 ± 15 MPa to 602 ± 10 MPa. [ABSTRACT FROM AUTHOR]

Materials' physicochemical properties largely pertain to their morphology and composition. This paper focuses on preparation and microwave absorbing properties (MAP) of surface-modified Co-Ni-P nanotubes (CTs). Cobalt was incorporated into as-synthesized Ni-P nanotubes(NTs) after surface modification processes, turning them into CTs with different element ratios. The above-mentioned processes have upgraded MAP of original NTs. Adequately low minimum reflection loss (R L ) has been obtained in CTs of all samples, with the lowest one (−57.8 dB) being achieved when n(Co):n(Ni)=2:3. The n(Co):n(Ni)=1:1 sample has the best comprehensive MAP, which have favorable R L , comparatively thin thicknesses, and broad absorbing band. [ABSTRACT FROM AUTHOR]

• Single-phase MnF 3 were prepared by high-temperature fluorination. • High-conductivity CNTs were incorporated by high-energy ball milling. • At 110 mA cm−2, the CNTs/MnF3 single cell exhibited high voltage of 3.46 V. • The thermal battery maintains a cell voltage above 1.5 V at 4.4 A cm−2. Metal fluoride is considered an ideal cathode material for high-voltage thermal batteries. Herein, single-phase MnF 3 were prepared by high-temperature fluorination and incorporated high-conductivity carbon nanotubes (CNTs) by high-energy activated ball milling. At a current density of 110 mA cm−2, the CNTs/MnF 3 single cell exhibited the cell voltage as high as 3.46 V, far exceeding others reported in the past. Moreover, it exhibits a short activation time of 0.66 s and maintains a cell voltage above 1.5 V at a high current density of 4.4 A cm−2. This work presents an effective cathode material for thermal battery with high cell voltage and long working time. [ABSTRACT FROM AUTHOR]

• We provide an alternative to the conventional Li-B alloy for thermal battery. • The Mg-doped Li-B alloy anode was prepared by high-temperature melting process. • The specific capacity of novel Mg-doped Li-B alloy is up to 4270 As/g. • The Li loading in novel Li-B anode is up to 64% and free Li is more than 40%. Thermal batteries with kilowatt power are crucial for improving the maneuverability of underwater weapons. Due to its high capacity, safety and stability, the new Li alloy anode has attracted extensive attention. In this study, Mg-doped Li-B alloy with high Li content was prepared by high temperature melting technology, and its Li loading was up to 64% and free Li content was more than 40%. The specific capacity of Mg-doped Li-B alloy was as high as 4270 As/g at the current density of 100 mA/cm2. Compared with the conventional Li-B alloy, the capacity of Mg-doped Li-B alloy is increased by 14.24%, and the specific energy can reach more than 140 Wh/kg. This work has guiding significance and great practical value for the research on high specific capacity anode for thermal battery. [ABSTRACT FROM AUTHOR]

Abstract: 22Ti–78Si(wt.%) eutectic braze was prepared through the non-consumable arc-melting technology. Wetting behavior of the braze on silicon carbide (SiC) was investigated by means of sessile drop method in vacuum at 1400 °C for 10 min. The result indicates that the braze exhibits good wettability (contact angle 25°) and adhesion with SiC. Main reasons are that TiC which owns higher surface energy is formed on SiC surface and the braze has an appropriate coefficient of thermal expansion (CTE) to that of SiC. [Copyright &y& Elsevier]

Abstract: The silicon carbide particles (SiCp) dispersion-strengthened copper matrix composites (Cu/SiCp) were fabricated by composite electroforming technology. The microstructure, tensile property and wear behavior of Cu/SiCp composites were investigated. The results showed that composites with different SiCp contents were obtained. The microstructure of the composite presented a uniform distribution of SiCp in the matrix and good interfacial integrity. The hardness, yield strength and rigidity of the composites increased with increasing SiCp content, but at the cost of ductility. Increasing SiCp content in the composite was not always beneficial to the ultimate tensile strength and wear resistance. The ultimate tensile strength increased with SiCp content increasing up to 16 vol.% and decreased as exceeding 16 vol.%, and the wear mass loss decreased with SiCp content increasing up to 21 vol.% and increased again as exceeding 21 vol.%. [Copyright &y& Elsevier]

Abstract: Electrodeposited nickel was prepared from a sulphamate bath at different current densities ranging from 0.01 A cm−2 to 0.1 A cm−2. Based on the analysis of the microstructure, the corrosion behavior of the electrodeposited nickel in 3.5%NaCl solution was studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). All the electrodeposits display active–passive–transpassive behavior in potentiodynamic polarization process. The electrodeposits with the best corrosion resistance are obtained at 0.05 A cm−2. As for other electrodeposits, the corrosion potential and breakdown potential decrease with increasing current density used to prepare electrodeposits. However, the variation of both corrosion current density and passive current density is opposite to that of the corrosion potential. The changes in the charge-transfer resistance determined from the impedance spectra are consistent with the results determined from potentiodynamic measurements. [Copyright &y& Elsevier]

Abstract: A new method of electrodeposition to prepare Ni/short carbon fibers (CFs) composites with network and sheet structures is described. The key point of the electrodeposition process is to obtain a sheet like preform floating on the electrolyte surface by froth flotation. The preform was composed of short homogeneous CFs. During the electrodeposition process, the preform was uniformly coated by nickel and the coating gradually grew from cathode to anode. The electrodeposits retained the network and sheet structures. The coating thickness can be controlled by appropriate electroplating conditions. The composites of epoxy resin reinforced by the electrodeposits were prepared successfully, and its electrical resistivity and electromagnetic shielding properties are reported. [Copyright &y& Elsevier]

The composite electroforming technology was propounded to fabricate silicon carbide powder (SiCp) reinforced copper-based composites. The influences of the concentration of SiCp in plating solution, the temperature of plating solution and current density on the SiCp content in Cu/SiCp composites were studied. Results showed that it could promote codeposition of Cu and SiCp and increase SiCp content in composites effectively through optimizing the technology parameters. Results of the study on thermal and mechanical properties of Cu/SiCp composites indicated that with SiCp content (vol.%) increasing, bend strength and HV (Vickers hardness) increased, but coefficient of thermal expansion (CTE) and conductivity factor decreased. In addition, internal stress existed in Cu/SiCp composites, which had influences on HV and thermal expansion property of Cu/SiCp composites. [Copyright &y& Elsevier]

• We provide a promising alternative cathode material for high-voltage thermal battery. • The NiCl 2 -based composite was prepared by hydrogen reduction strategy. • The NiCl 2 -based cell exhibits superior pulse discharge and fast activation ability. NiCl 2 is regarded as an ideal cathode material for high-voltage thermal battery. However, the difficulty of preparation and low inherent conductivity have become the major challenge to hinder practical application of NiCl 2 material. Herein, the reduced NiCl 2 with Ni as conductive agent has been developed via a facile hydrogen reduction. When served as cathode for thermal battery, the NiCl 2 -based composite exhibits high peak voltage of 2.51 V and short activation time of 0.67 s, accompanying with superior pulse discharge capacity. This work provides a promising alternative for high-voltage cathode and is beneficial to guide the further application of NiCl 2 materials. [ABSTRACT FROM AUTHOR]

• Pure Zn and Zn-epoxy powder coatings was prepared by zincate electrodeposition. • The addition of epoxy powder improves microstructures and reduce roughness. • The incorporation of epoxy powder enhances the corrosion resistance. • The incorporation of epoxy powder hinders the hydrogen permeation. • The addition of epoxy powder improves the wear resistance. To improve the corrosion and wear resistance of the coating and reduce the effect of hydrogen penetration on the performance of galvanized steel, Zinc-epoxy powder (EP) composite coatings were prepared by alkaline zincate electrodeposition. The results show that the Zn-6 g/L EP coating has the lowest root mean square roughness of 281.99 A. The incorporation of EP enhances the corrosion resistance of the coating. The Zn-6 g/L EP coating has the largest coating resistance and charge transfer resistance. The incorporation of EP can hinder the hydrogen permeation, which may reduce the hydrogen embrittlement of galvanized steel. Tribological experiment shows that the wear resistance of the composite coating is improved. The friction coefficient and wear scar width of the Zn-12 g/L EP coating is the lowest. [ABSTRACT FROM AUTHOR]

• DL-EPR was used to describe the precipitation of carbides in super Cr13 stainless steel. • The main reason for the decrease in impact toughness is the precipitation of continuous Cr-rich carbides (M23C6) along the interface. • Solution treatment before quenching and tempering treatment can improve the impact toughness. • The impact tough of the steel can be predicted by DL-EPR. Super martensitic stainless steel (SMSS) is characterized by improved mechanical properties and corrosion resistance. However, during production the impact toughness will be significantly reduced under certain heat treatment regimes (tempering at 873 K followed by quenching at 1213 K and tempering at 913 K). Double loop electrochemical potentiokinetic reactivation (DL-EPR) were used to investigate the mechanism for the reduction of impact toughness in this experiment. It was found that the primary cause for the decrease was precipitation of continuously distributed Cr-rich carbides (M 23 C 6) along martensite lath boundaries. The Ra value obtained by DL-EPR is positively correlated with the amount of Cr-rich carbide precipitation. As Ra increases, impact toughness increases first and then decreases rapidly, which indicates that it is reasonable to use Ra to qualitatively predict the impact toughness of the steel. [ABSTRACT FROM AUTHOR]

Abstract: An ultrafine-grained surface layer was fabricated on a pure Fe plate by the shot peening process. The average grain size within the surface layer of 10μm thick is about 28nm. The diffusion kinetics of Al was measured by secondary ion mass spectrometry within a temperature range of 300–380°C. The diffusion coefficient of Al in the nanocrystalline layer is about 4 orders of magnitude higher than that in coarse-grained Fe. The activation energy of Al diffusion in nanocrystalline layer is 1.38eV, which is much smaller than that reported for Al diffusion in the conventional Fe. The enhanced diffusivity of Al may originate from a considerable amount of nonequilibrium grain boundaries and a high density of dislocations in the surface layer processed by shot peening. [Copyright &y& Elsevier]

Abstract: Ni hollow spheres (NHSs) have been successfully synthesized through a microemulsion–template–interface reaction route. The structures of NHSs were characterized by X-ray powder diffraction (XRD), selected area electron diffraction (SAED), transmission electron microscopy (TEM). The results showed that the size of the NHSs was between 50 to 150nm. The shell thickness of the NHSs is about 20nm. In our method, the metal precursor and reducing agent dissolved in two different phases; they can react at oil/water interface. Thus, hollow spheres can be fabricated more easily. [Copyright &y& Elsevier]