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Recent progress in material data mining has been driven by high-capacity models trained on large datasets. However, collecting experimental data has been extremely costly owing to the amount of human effort and expertise required. Therefore, material researchers are often reluctant to easily disclose their private data, which leads to the problem of data island, and it is difficult to collect a large amount of data to train high-quality models. In this study, a material microstructure image feature extraction algorithm FedTransfer based on data privacy protection is proposed. The core contributions are as follows: 1) the federated learning algorithm is introduced into the polycrystalline microstructure image segmentation task to make full use of different user data to carry out machine learning, break the data island and improve the model generalization ability under the condition of ensuring the privacy and security of user data; 2) A data sharing strategy based on style transfer is proposed. By sharing style information of images that is not urgent for user confidentiality, it can reduce the performance penalty caused by the distribution difference of data among different users., Comment: 14 pages

In this work, we propose a novel unsupervised deep learning model to address multi-focus image fusion problem. First, we train an encoder-decoder network in unsupervised manner to acquire deep feature of input images. And then we utilize these features and spatial frequency to measure activity level and decision map. Finally, we apply some consistency verification methods to adjust the decision map and draw out fused result. The key point behind of proposed method is that only the objects within the depth-of-field (DOF) have sharp appearance in the photograph while other objects are likely to be blurred. In contrast to previous works, our method analyzes sharp appearance in deep feature instead of original image. Experimental results demonstrate that the proposed method achieves the state-of-art fusion performance compared to existing 16 fusion methods in objective and subjective assessment., Comment: technological report and fix some errors

Deep learning has driven a great progress in natural and biological image processing. However, in material science and engineering, there are often some flaws and indistinctions in material microscopic images induced from complex sample preparation, even due to the material itself, hindering the detection of target objects. In this work, we propose WPU-net that redesigns the architecture and weighted loss of U-Net, which forces the network to integrate information from adjacent slices and pays more attention to the topology in boundary detection task. Then, the WPU-net is applied into a typical material example, i.e., the grain boundary detection of polycrystalline material. Experiments demonstrate that the proposed method achieves promising performance and outperforms state-of-the-art methods. Besides, we propose a new method for object tracking between adjacent slices, which can effectively reconstruct 3D structure of the whole material. Finally, we present a material microscopic image dataset with the goal of advancing the state-of-the-art in image processing for material science., Comment: technical report

Recent progress in material data mining has been driven by high-capacity models trained on large datasets. However, collecting experimental data (real data) has been extremely costly since the amount of human effort and expertise required. Here, we develop a novel transfer learning strategy to address small or insufficient data problem. This strategy realizes the fusion of real and simulated data, and the augmentation of training data in data mining procedure. For a specific task of image segmentation, this strategy can generate synthetic images by fusing physical mechanism of simulated images and "image style" of real images. The result shows that the model trained with the acquired synthetic images and 35% of the real images outperforms the model trained on all real images. As the time required to generate synthetic data is almost negligible, this strategy is able to reduce the time cost of real data preparation by roughly 65%., Comment: 17 pages, technical report

Systematically experimental investigations were conducted on H-doped 0.91Pb(Zn1/3Nb2/3)O-3-0.09PbTiO(3) (PZNT) single crystals and lead zirconate titanate (PZT) ceramics. The experimental results show that doping hydrogen with appropriate content advances the ferroelectric and piezoelectric properties effectively. For example, when trapped hydrogen concentration was C-1 = 1.7 wppm in the H-doped PZNT single crystals, the remanent polarization P-r and piezoelectric constant d(33) increased by 80\% and 41.7\% in comparison with the H-free samples, respectively, to 28.8 mu C/cm(2) and 391 pC/N. However, high hydrogen concentration damages the ferroelectric and piezoelectric properties. The remanent polarization P-r and piezoelectric constant d(33) of the H-doped PZNT single crystals decreased to 0 mu C/cm(2) and 24 pC/N, respectively, when C-1 = 3.1 wppm. The H-doped PZT ceramics exhibited the same behavior, where the values of P-r and d(33) increased respectively by 45.3\% and 27.3\% to 48.1 mu C/cm(2) and 420 pC/N, when C-t = 1.1 wppm, and decreased to 0 mu C/cm(2) and 84 pC/N, respectively, as C-t increased to 2.1 wppm. Hydrogen also increases the dielectric constant and dielectric loss for both ferroelectric materials. The experimental results indicate that doping hydrogen into ferroelectric materials is a feasible technique to tune the ferroelectric and piezoelectric properties effectively, furthermore as a subsequent treated technology for the ferroelectric product.

Systematically experimental investigations were conducted on H-doped 0.91Pb(Zn1/3Nb2/3)O-3-0.09PbTiO(3) (PZNT) single crystals and lead zirconate titanate (PZT) ceramics. The experimental results show that doping hydrogen with appropriate content advances the ferroelectric and piezoelectric properties effectively. For example, when trapped hydrogen concentration was C-1 = 1.7 wppm in the H-doped PZNT single crystals, the remanent polarization P-r and piezoelectric constant d(33) increased by 80\% and 41.7\% in comparison with the H-free samples, respectively, to 28.8 mu C/cm(2) and 391 pC/N. However, high hydrogen concentration damages the ferroelectric and piezoelectric properties. The remanent polarization P-r and piezoelectric constant d(33) of the H-doped PZNT single crystals decreased to 0 mu C/cm(2) and 24 pC/N, respectively, when C-1 = 3.1 wppm. The H-doped PZT ceramics exhibited the same behavior, where the values of P-r and d(33) increased respectively by 45.3\% and 27.3\% to 48.1 mu C/cm(2) and 420 pC/N, when C-t = 1.1 wppm, and decreased to 0 mu C/cm(2) and 84 pC/N, respectively, as C-t increased to 2.1 wppm. Hydrogen also increases the dielectric constant and dielectric loss for both ferroelectric materials. The experimental results indicate that doping hydrogen into ferroelectric materials is a feasible technique to tune the ferroelectric and piezoelectric properties effectively, furthermore as a subsequent treated technology for the ferroelectric product.

In this work, we develop further the microbridge testing method by deriving a closed formula of deflection versus load, which is applied at an arbitrary position on the microbridge beam. Testing a single beam at various positions allows us to characterize simultaneouslyYoung's modulus and residual stress of the beam. The developed method was then used to characterize the mechanical properties of GaN thin films on patterned-Si (1 1 1) substrates grown by metal organic chemical vapor deposition (MOCVD). The microbridge samples were fabricated by using the microelectromechanical fabrication technique and tested with a nanoindentation system. Young's modulus and residual stress of the GaN films were determined to be 287 +/- 190 GPa and 851 +/- 155 MPa, respectively. In addition, alternative measurements of the residual stress, Young's modulus and hardness of the GaN films, were conducted with micro-Raman spectroscopy and the nanoindentation test, yielding the corresponding values of 847 +/- 46 MPa, 269.0 +/- 7.0 GPa and 17.8 +/- 1.1 GPa.

The Energy-Dispersive-X-ray-based permeation and oxidation test has been further developed by an improved theoretical analysis, in which chemical potential gradients rather than concentration gradients are employed. The developed test is able to characterize diffusion kinetics in diffusion barriers at the nanometer scale. The Cu flux coefficient in (Cu, Ni)(3)Sn intermetallic compound nanolayers was determined from the test to be 8.48 x 10(-15) mol.(m.s.J/mol)(-1) exp(-52.3 kJ.mol(-1)/RT) in a temperature range of 250 degrees C-400 degrees C. (C) 2009 Elsevier B.V. All rights reserved.

Dendrite-like ZnO@Ag heterostructure nanocrystals are designed and fabricated by a facial two-step chemical method in a large scale. The heterostructure nanocrystals are composed of single crystal Ag nanowires as trunks and highly dense (0001) oriented ZnO nanorods as branches. ZnO nanorods with diameters of about 50-400 nm are vertically grown on the six lateral surfaces of the Ag nanowires. Ultrathin ZnO nanowires or nanotubes with a diameter of less than 30 rim are decorated on the ZnO nanorods. The photocatalysis test shows that the ZnO@Ag heterostructures exhibit a higher photocatalytic activity than the pure ZnO nanorods, thereby implying that the Ag/ZnO interfaces promote the separation of photogenerated electron-hole pairs and enhance the photocatalytic activity.

The present work conducts crystal characterization by High Resolution Transmission Electron Microscopy (HRTEM) on Cu/Sn-nanolayer/Ni sandwich structures associated with the use of Energy Dispersive X-ray (EDX) analysis. The results show that DO22-(Cu,Ni)(3)Sn intermetallic compound (IMC) ordered structure is formed in the sandwich structures at the as-electrodeposited state. The formed DO22-(Cu,Ni)(3)Sn IMC is a homogeneous layer with a thickness about 10 nm. The DO22-(Cu,Ni)(3)Sn IMC nanolayer is stable during annealing at 250 degrees C for 810 min. The formation and stabilization of the metastable DO22-(Cu,Ni)(3)Sn IMC nanolayer are attributed to the less strain energy induced by lattice mismatch between the DO22 IMC and fcc Cu crystals in comparison with that between the equilibrium DO3 IMC and fcc Cu crystals. (C) 2009 Elsevier B.V. All rights reserved.

The Energy-Dispersive-X-ray-based permeation and oxidation test has been further developed by an improved theoretical analysis, in which chemical potential gradients rather than concentration gradients are employed. The developed test is able to characterize diffusion kinetics in diffusion barriers at the nanometer scale. The Cu flux coefficient in (Cu, Ni)(3)Sn intermetallic compound nanolayers was determined from the test to be 8.48 x 10(-15) mol.(m.s.J/mol)(-1) exp(-52.3 kJ.mol(-1)/RT) in a temperature range of 250 degrees C-400 degrees C. (C) 2009 Elsevier B.V. All rights reserved.

Dendrite-like ZnO@Ag heterostructure nanocrystals are designed and fabricated by a facial two-step chemical method in a large scale. The heterostructure nanocrystals are composed of single crystal Ag nanowires as trunks and highly dense (0001) oriented ZnO nanorods as branches. ZnO nanorods with diameters of about 50-400 nm are vertically grown on the six lateral surfaces of the Ag nanowires. Ultrathin ZnO nanowires or nanotubes with a diameter of less than 30 rim are decorated on the ZnO nanorods. The photocatalysis test shows that the ZnO@Ag heterostructures exhibit a higher photocatalytic activity than the pure ZnO nanorods, thereby implying that the Ag/ZnO interfaces promote the separation of photogenerated electron-hole pairs and enhance the photocatalytic activity.

The present work conducts crystal characterization by High Resolution Transmission Electron Microscopy (HRTEM) on Cu/Sn-nanolayer/Ni sandwich structures associated with the use of Energy Dispersive X-ray (EDX) analysis. The results show that DO22-(Cu,Ni)(3)Sn intermetallic compound (IMC) ordered structure is formed in the sandwich structures at the as-electrodeposited state. The formed DO22-(Cu,Ni)(3)Sn IMC is a homogeneous layer with a thickness about 10 nm. The DO22-(Cu,Ni)(3)Sn IMC nanolayer is stable during annealing at 250 degrees C for 810 min. The formation and stabilization of the metastable DO22-(Cu,Ni)(3)Sn IMC nanolayer are attributed to the less strain energy induced by lattice mismatch between the DO22 IMC and fcc Cu crystals in comparison with that between the equilibrium DO3 IMC and fcc Cu crystals. (C) 2009 Elsevier B.V. All rights reserved.

In this work, we develop further the microbridge testing method by deriving a closed formula of deflection versus load, which is applied at an arbitrary position on the microbridge beam. Testing a single beam at various positions allows us to characterize simultaneouslyYoung's modulus and residual stress of the beam. The developed method was then used to characterize the mechanical properties of GaN thin films on patterned-Si (1 1 1) substrates grown by metal organic chemical vapor deposition (MOCVD). The microbridge samples were fabricated by using the microelectromechanical fabrication technique and tested with a nanoindentation system. Young's modulus and residual stress of the GaN films were determined to be 287 +/- 190 GPa and 851 +/- 155 MPa, respectively. In addition, alternative measurements of the residual stress, Young's modulus and hardness of the GaN films, were conducted with micro-Raman spectroscopy and the nanoindentation test, yielding the corresponding values of 847 +/- 46 MPa, 269.0 +/- 7.0 GPa and 17.8 +/- 1.1 GPa.

In this work, we develop further the microbridge testing method by deriving a closed formula of deflection versus load, which is applied at an arbitrary position on the microbridge beam. Testing a single beam at various positions allows us to characterize simultaneouslyYoung's modulus and residual stress of the beam. The developed method was then used to characterize the mechanical properties of GaN thin films on patterned-Si (1 1 1) substrates grown by metal organic chemical vapor deposition (MOCVD). The microbridge samples were fabricated by using the microelectromechanical fabrication technique and tested with a nanoindentation system. Young's modulus and residual stress of the GaN films were determined to be 287 +/- 190 GPa and 851 +/- 155 MPa, respectively. In addition, alternative measurements of the residual stress, Young's modulus and hardness of the GaN films, were conducted with micro-Raman spectroscopy and the nanoindentation test, yielding the corresponding values of 847 +/- 46 MPa, 269.0 +/- 7.0 GPa and 17.8 +/- 1.1 GPa.

The Energy-Dispersive-X-ray-based permeation and oxidation test has been further developed by an improved theoretical analysis, in which chemical potential gradients rather than concentration gradients are employed. The developed test is able to characterize diffusion kinetics in diffusion barriers at the nanometer scale. The Cu flux coefficient in (Cu, Ni)(3)Sn intermetallic compound nanolayers was determined from the test to be 8.48 x 10(-15) mol.(m.s.J/mol)(-1) exp(-52.3 kJ.mol(-1)/RT) in a temperature range of 250 degrees C-400 degrees C. (C) 2009 Elsevier B.V. All rights reserved.

Dendrite-like ZnO@Ag heterostructure nanocrystals are designed and fabricated by a facial two-step chemical method in a large scale. The heterostructure nanocrystals are composed of single crystal Ag nanowires as trunks and highly dense (0001) oriented ZnO nanorods as branches. ZnO nanorods with diameters of about 50-400 nm are vertically grown on the six lateral surfaces of the Ag nanowires. Ultrathin ZnO nanowires or nanotubes with a diameter of less than 30 rim are decorated on the ZnO nanorods. The photocatalysis test shows that the ZnO@Ag heterostructures exhibit a higher photocatalytic activity than the pure ZnO nanorods, thereby implying that the Ag/ZnO interfaces promote the separation of photogenerated electron-hole pairs and enhance the photocatalytic activity.

The present work conducts crystal characterization by High Resolution Transmission Electron Microscopy (HRTEM) on Cu/Sn-nanolayer/Ni sandwich structures associated with the use of Energy Dispersive X-ray (EDX) analysis. The results show that DO22-(Cu,Ni)(3)Sn intermetallic compound (IMC) ordered structure is formed in the sandwich structures at the as-electrodeposited state. The formed DO22-(Cu,Ni)(3)Sn IMC is a homogeneous layer with a thickness about 10 nm. The DO22-(Cu,Ni)(3)Sn IMC nanolayer is stable during annealing at 250 degrees C for 810 min. The formation and stabilization of the metastable DO22-(Cu,Ni)(3)Sn IMC nanolayer are attributed to the less strain energy induced by lattice mismatch between the DO22 IMC and fcc Cu crystals in comparison with that between the equilibrium DO3 IMC and fcc Cu crystals. (C) 2009 Elsevier B.V. All rights reserved.