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As a hot research field at present, computer vision is devoted to the rapid acquisition and application of target information from images or videos by simulating human visual mechanism. In order to improve the accuracy and efficiency of image detection, image saliency region detection technology has received more and more attention in the field of computer vision research; an important research content in the field, the core part of which lies in the research on algorithms related to feature extraction and saliency calculation of targets. This paper analyzes the multi‐feature fusion saliency detection model and visual saliency calculation process, and based on the existing algorithm, by improving the VGG16 network, a fully convolutional network saliency detection algorithm is proposed. The qualitative and quantitative experimental results show that compared with the four mainstream methods of BL, GS, SF, and RFCN, our algorithm not only improves the accuracy of salient object detection, but also effectively solves the problem of target edge blur. Therefore, this study has improved the accuracy and efficiency of saliency detection, which can not only promote the development of computer vision technology, but also provide support for research in the field of image processing. [ABSTRACT FROM AUTHOR]

In this study, (La 0.2 Gd 0.2 Y 0.2 Sm 0.2 Ce 0.2) 2 Zr 2 O 7 ((LGYSC)ZO)), as a new type of thermal barrier coating material, was designed and synthesized. The lattice structure, microstructure, optical, thermophysical, and mechanical properties of the (LGYSC)ZO high-entropy oxide were also investigated. The results showed that a phase-pure pyrochlore-structure (LGYSC)ZO high-entropy oxide, which has a uniform elemental distribution at high temperatures, was successfully synthesized. In addition, the UV–Vis diffuse reflectance spectra results show that (LGYSC)ZO high-entropy oxide has direct and indirect bandgap widths of 3.10eν and 2.51eν, respectively. Infrared (IR) spectra of (LGYSC)ZO high-entropy oxide patterns were measured. The infrared spectra results show that the (LGYSC)ZO high-entropy oxide has better high temperature thermal radiation shielding performance than yttria stabilized zirconia(YSZ). According to the measured result by laser flash method, the thermal conductivity of (LGYSC)ZO high-entropy oxide is at range from 1.18 W m−1 K−1 to 1.37 W m−1 K−1 in the temperature regime from 200 °C to 1000 °C after porosity correction. The coefficient of thermal expansion (CTE) of (LGYSC)ZO high-entropy oxides is at range from about 7.79 × 10−6 k−1 to 11.1 × 10−6 k−1 corresponding temperature from 90 °C to 1000 °C. The mechanical properties of (LGYSC)ZO high-entropy oxides were also investigated, and the hardness and fracture toughness of (LGYSC)ZO high-entropy oxide were 6.61 GPa and 1.27 MPa m1/2, respectively. Therefore, the results indicate that (LGYSC)ZO has excellent properties as a promising thermal barrier coating material. [ABSTRACT FROM AUTHOR]

Lexical ability, an umbrella term to cover various knowledge and skills pertaining to words in print, is a key component in reading comprehension. Little is known how different facets of lexical ability jointly contribute to L2 reading comprehension and how the contributions may differ between higher- and lower-proficiency L2 learners. This study, based on 201 adults who had studied Chinese in China, explored direct and indirect effects of distinct facets of lexical ability on L2 reading comprehension. The participants completed three paper-pencil tasks that measured three facets of lexical ability, that is, morphological awareness, character knowledge, and vocabulary knowledge. Their short-term memory, grammatical knowledge, and reading comprehension were also measured. Separate sets of path analysis showed that higher- and lower-proficiency learners had distinct patterns of relationships. Whereas higher-proficiency learners relied more on morphological awareness and vocabulary knowledge in L2 Chinese reading comprehension, lower-proficiency learners drew largely upon their character knowledge. [ABSTRACT FROM AUTHOR]

In this study, (La 0.2 Gd 0.2 Y 0.2 Sm 0.2 Ce 0.2) 2 Zr 2 O 7 ((LGYSC)ZO)), as a new type of thermal barrier coating material, was designed and synthesized. The lattice structure, microstructure, optical, thermophysical, and mechanical properties of the (LGYSC)ZO high-entropy oxide were also investigated. The results showed that a phase-pure pyrochlore-structure (LGYSC)ZO high-entropy oxide, which has a uniform elemental distribution at high temperatures, was successfully synthesized. In addition, the UV–Vis diffuse reflectance spectra results show that (LGYSC)ZO high-entropy oxide has direct and indirect bandgap widths of 3.10eν and 2.51eν, respectively. Infrared (IR) spectra of (LGYSC)ZO high-entropy oxide patterns were measured. The infrared spectra results show that the (LGYSC)ZO high-entropy oxide has better high temperature thermal radiation shielding performance than yttria stabilized zirconia(YSZ). According to the measured result by laser flash method, the thermal conductivity of (LGYSC)ZO high-entropy oxide is at range from 1.18 W m−1 K−1 to 1.37 W m−1 K−1 in the temperature regime from 200 °C to 1000 °C after porosity correction. The coefficient of thermal expansion (CTE) of (LGYSC)ZO high-entropy oxides is at range from about 7.79 × 10−6 k−1 to 11.1 × 10−6 k−1 corresponding temperature from 90 °C to 1000 °C. The mechanical properties of (LGYSC)ZO high-entropy oxides were also investigated, and the hardness and fracture toughness of (LGYSC)ZO high-entropy oxide were 6.61 GPa and 1.27 MPa m1/2, respectively. Therefore, the results indicate that (LGYSC)ZO has excellent properties as a promising thermal barrier coating material. [ABSTRACT FROM AUTHOR]

In the magnetic-suspension bearing-rotor system, the shape features of the rotor axis trajectory can directly reflect the system operation status and fault information. Accurately classifying the bearing faults can promptly find the cause of the fault and respond quickly and protect it. In this paper, in order to achieve fault identification by identifying and classifying the rotor axis trajectory, we use Hu moment invariants to extract feature vectors from the rotor axis trajectory to identify faults. We use imperial competitive algorithm to reduce redundant data and establish a directed acyclic graph support vector machine to classify and identify feature data. Compared with traditional classification models such as C4.5 and BP neural networks, the experimental results show that the support vector machine model based on Hu moment invariants and simulated annealing has a higher accuracy and robustness in small sample classification. It is suitable for intelligent identification and classification for bearing faults. [ABSTRACT FROM AUTHOR]

This article synthesizes the roles of morphology in English reading acquisition and reports a meta-analytic structural equation modeling study (k = 107, N = 21,818) that tested the effects of morphological awareness (MA) on reading comprehension in school-aged readers. Moderator analysis was conducted through a set of subgroup comparisons based on readers' language status (monolingual vs. bilingual), age/grade (lower elementary, upper elementary, vs. middle/high school), and MA task modality (spoken vs. written). MA had significant indirect effects on reading comprehension via both word reading and vocabulary knowledge in the full sample as well as all subgroups. Its direct effect on reading comprehension, controlling for nonverbal reasoning, word reading, and vocabulary knowledge, was also significant in all subgroups except the lower elementary subgroup. Multi-group path analyses showed no significant subgroup difference in the magnitude of the direct effect of MA on reading comprehension for any moderator. However, two notable findings surfaced on the indirect effects of MA on reading comprehension: bilingual readers showed a smaller indirect effect of MA via word reading than did monolinguals; older readers showed a stronger indirect effect via vocabulary knowledge than did younger readers, whereas a converse pattern was found for the indirect effect via word reading. We conclude by pointing out the robust contribution of morphology to English reading comprehension and suggesting a strong meaning focus in morphological instruction, especially for bilingual and older school-aged readers. Educational Impact and Implications Statement: English is characterized by an abundance of morphologically complex words, that is, words with two or more meaningful components such as affixes and roots. This means children's insights into the components and structure of these words (i.e., MA) are important for reading acquisition and development. How MA may contribute to reading comprehension has remained unclear. This meta-analysis of correlations found that MA influences reading comprehension indirectly through word reading and vocabulary knowledge, as well as directly over and above these two word-level competencies. Variations in these relations were also found between monolingual and bilingual readers of English and between children differing in age/grade. These findings suggested that morphological instruction may need to be differentiated and responsive to children's language status and stage of schooling. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings are an effective technology for improving the high-temperature performance of hot section components in gas turbine engine. Due to their excellent properties, high-entropy oxides are considered to be promising materials for thermal barrier coatings. Laser cladding is a coating preparation technology and the top coat prepared by laser cladding technology has an important application value for thermal barrier coatings. In this work, to improve the thermal cycling behavior of the La 2 (Ti 0.2 Zr 0.2 Sn 0.2 Ce 0.2 Hf 0.2) 2 O 7 high-entropy oxide coating, a bi-layer coating with the La 2 (Ti 0.2 Zr 0.2 Sn 0.2 Ce 0.2 Hf 0.2) 2 O 7 high-entropy oxide layer and the YSZ layer was designed and fabricated by laser cladding on the NiCoCrAlY alloy surface. The microstructure, phase and mechanical properties of the coating were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and micro-hardness and nanoindentation tests, respectively. The results show that a bi-layer La 2 (Ti 0.2 Zr 0.2 Sn 0.2 Ce 0.2 Hf 0.2) 2 O 7 /YSZ coating was successfully prepared by the laser cladding method, and shows good bonding at the interface between the layers. The high-entropy oxide layer maintains a relatively stable defective fluorite structure and its microstructure exists in the stable cellular and dendrite crystalline state after laser cladding. The high-entropy oxide layer prepared by laser cladding showed an average elastic modulus of 167 GPa and an average hardness of 1022.8HV in nanoindentation tests. Thermal cycling of the coating was carried out at 1050 °C. Failure of the bi-layer coating occurred after 60 thermal cycles at 1050 °C. Thermal stresses between different layers are calculated during thermal cycling. Due to its excellent mechanical properties, the bi-layer coating with the La 2 (Ti 0.2 Zr 0.2 Sn 0.2 Ce 0.2 Hf 0.2) 2 O 7 high-entropy oxide and YSZ layers is expected to become an effective high-entropy oxide thermal barrier coating. [ABSTRACT FROM AUTHOR]

The interpretability of the model is a hot issue in the field of computer vision. Score‐CAM is a kind of interpretable CAM method with good discrimination and gradient free calculation. It is a representative work in this field. However, it has the disadvantages of long calculation time and incomplete heatmap coverage. Therefore, this paper proposes an improved Score‐CAM method named FIMF Score‐CAM, which can fast integrate multiple features. Its contribution is reflected in two aspects: The weight of the feature map is directly calculated by using the feature template. Unlike Score‐CAM, this model greatly saves computation time because it only requires one convolutional calculation. Another contribution is that the feature map used to generate the heatmap integrates various semantic features of the local space, so that the heatmap of the object of interest can be generated with more complete coverage and better interpretation. The FIMF Score‐CAM is superior to the existing mainstream models in interpreting the visual performance and fairness indicators of the decision‐making, having more complete explanations of object classes and the advantage of faster calculation speed. [ABSTRACT FROM AUTHOR]

This letter proposed a coupled resonant inductor structure for CLLC bidirectional converter, which can effectively reduce the number and volume of magnetic components and the oscillation caused by parasitic parameters. An optimized current detection method based on magnetic element voltage detection is also proposed to avoid the use of bulky and costly current sensors. Synchronous rectification is realized with the detection to improve efficiency. The effectiveness is verified by a 3 kW CLLC converter. [ABSTRACT FROM AUTHOR]

Bidirectional wireless power transfer greatly improves the reliability of power supply. However, wireless communication between the primary and pickup controllers is usually required to transmit load information, which has time delay and is easily interfered by electromagnetic fields. Existing solutions to avoid the use of communication can be divided into three categories: additional dc/dc circuit, primary side bridge control, and secondary side bridge control. Compared with the other two methods, the secondary side bridge control has low loss and good robustness. But, it usually requires phase-locked loop (PLL) to eliminate the frequency error between primary and secondary side bridges, which increases the complexity. In this article, a constant current control strategy without communication is proposed. It is based on the secondary side bridge control and the switching sequence of the secondary side bridge is periodically synchronized according to the phase of the resonant current. It works robustly without the need for additional hardware such as PLL or Multiplier. The harmonic sensitivity analysis, parameter optimization design and stability analysis are carried out to improve the control efficiency. Experimental results based on a 1 kW prototype with dual LCC resonant network are presented to verify the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

As a type of representative bunch-type fruit, the collision-free and undamaged harvesting of grapes is of great significance. To obtain accurate 3D spatial semantic information, this paper proposes a method for multi-feature enhanced semantic segmentation model based on Mask R-CNN and PointResNet(improved PointNet++). Firstly, a depth camera is used to obtain RGBD images. The RGB images are then inputted into the Mask-RCNN network for fast detection of grape bunches. The color and depth information are fused and transformed into point cloud data, followed by the estimation of normal vectors. Finally, the nine-dimensional point cloud, which include spatial location, color information, and surface structure information, are inputted into the PointResNet network to achieve semantic segmentation of grape bunches, peduncles, and leaves. This process obtains the extraction of spatial semantic information from the surrounding area of the bunches. The experimental results show that by incorporating normal vector and color features, the overall accuracy of point cloud segmentation increases to 96.5%, with a mean accuracy of 90.3%. This represents a significant improvement of 7.9% and 16.6% compared to using only positional features. The results demonstrate that the model method presented in this paper can effectively provide precise 3D semantic information to the robot while ensuring both speed and accuracy. This lays the groundwork for subsequent collision-free and undamaged picking. • 2D detection locates grape bunches, extracting regions of interest. • 3D point cloud segmentation identifies grape parts—bunches, peduncles, leaves. • Improved point cloud segmentation network adapts to grape scenes. • Enhanced features for better accuracy. • Experiments show superior recognition using 3D point clouds. [ABSTRACT FROM AUTHOR]

In this paper, the model and its curriculum learning method of garbage hierarchical classification and corresponding operation mode decision in home environment are proposed from the perspective of cleaning robot. In order to realize the hierarchical learning of garbage attribute concept, this paper designs a learning model with iterative feedback network as the backbone network. In the early stage of iteration, the model focuses on learning the state of garbage, in the middle stage, it focuses on the appearance attributes of garbage, and the specific categories of garbage in the later stage. At the same time, the attention module is introduced to achieve different levels of feature expression learning, which further improves the performance of the model. The evaluation was conducted on the collected garbage data set and the public CIFAR-100 and Stanford Cars data sets, which verified the effectiveness and wide applicability of the proposed method. [ABSTRACT FROM AUTHOR]

This study compared how distinct lexical competences, including lexical knowledge as well as processing skills at both word/lexical and sublexical/morphological levels, collectively and relatively predict reading comprehension in adult learners of English as a foreign language (EFL). The participants were 220 Arabic‐speaking EFL learners in a Saudi university. A battery of paper‐ and computer‐based tests was administered to measure the participants' lexical competences, reading comprehension ability, and working memory. Hierarchical regression analyses revealed that over and above working memory, both lexical and sublexical knowledge were significant and unique predictors of reading comprehension, and sublexical processing efficiency, as opposed to lexical processing efficiency, predicted reading comprehension significantly. In addition, among the measured lexical competences, lexical knowledge was the strongest predictor, and the two knowledge variables collectively had a far greater influence on reading comprehension than did the two processing efficiency variables. These findings are discussed in light of the lexical basis of text comprehension. [ABSTRACT FROM AUTHOR]

Multilevel thresholding image segmentation has always been a popular issue and attracted the attention of many researchers in recent years since it has many applications. However, the process of determining the optimal thresholds in the case of multilevel thresholding is time-consuming. To address this problem, in this paper, the optimal thresholds for multilevel thresholding image segmentation are obtained by maximizing the Rényi entropy using the Lévy flight firefly algorithm (FAFA), in which an adaptive parameter strategy based on Lévy flight is used to improve the performance of the standard firefly algorithm (FA). The performance of the proposed algorithm has been evaluated using several benchmark images and has been compared with five different heuristic algorithms. The experimental results showed that the proposed algorithm prevailed over the other five competitive algorithms in terms of the objective function value, image quality measures, and computational efficiency. [ABSTRACT FROM AUTHOR]

In this study, we quantified the vegetation changes in the Haihe river basin (HRB) and analyzed their drivers during 1982–2012 by using satellite normalized difference vegetation index (NDVI) data, observation-based climate data, satellite vegetation continuous fields (VCF) data, and soil moisture (SM) data. The results showed that the increases in NDVI was the largest in autumn (2.12 × 10−3), followed by growing-season (1.97 × 10−3), spring (1.82 × 10−3), annual (1.35 × 10−3), summer (1.15 × 10−3), and winter (0.32 × 10−3). The VCF, mean annual temperature (MAT), SM, and mean annual precipitation (MAP) determined the NDVI changes in 44.43%, 27.69%, 5.33%, and 2.01% of the HRB, respectively. In the western and southern HRB, MAT and VCF were the dominant factors, besides, SM was one of the important factors in the western HRB. Therefore, the study identified that SM, MAT, and human activities (Changes in VCF) were the main factors that determined the changes in vegetation over HRB. [ABSTRACT FROM AUTHOR]

A pyrochlore-structured La 2 (Zr 0.2 Ce 0.2 Hf 0.2 Sn 0.2 Ti 0.2) 2 O 7 high-entropy oxide was designed and synthesized, and its properties were tested. Traditional two-layer structured thermal barrier coatings (TBCs) with a La 2 (Zr 0.2 Ce 0.2 Hf 0.2 Sn 0.2 Ti 0.2) 2 O 7 top-coat were prepared by plasma spraying. A phase-pure defective-fluorite high-entropy-oxide top coat was thus obtained. The results confirmed the possibility of synthesizing pyrochlore-structured La 2 (Zr 0.2 Ce 0.2 Hf 0.2 Sn 0.2 Ti 0.2) 2 O 7. The material exhibited a low thermal conductivity, which increased with increasing temperature. The coefficient of thermal expansion (CTE) of La 2 (Zr 0.2 Ce 0.2 Sn 0.2 Hf 0.2 Ti 0.2) 2 O 7 ranged from 7.55 × 10−6 °C−1 to 8.63 × 10−6 °C−1 for the corresponding range of room temperature to 1000 °C. After 10 thermal cycles at 1050 °C, the La 2 (Zr 0.2 Ce 0.2 Hf 0.2 Sn 0.2 Ti 0.2) 2 O 7 top coat spalled in the TBC. Spallation did not occur at the interface between the bond coat and the thermally grown oxide layer, while it is in the top coat near the bond coat. Owing to the low fracture toughness and low CTE, the thermal cycling lifetime of TBCs with the La 2 (Zr 0.2 Ce 0.2 Hf 0.2 Sn 0.2 Ti 0.2) 2 O 7 top coat was short. [ABSTRACT FROM AUTHOR]

Object detection is an essential technology in the computer vision domain and plays a vital role in intelligent transportation. Intelligent vehicles utilize object detection on images for environment perception. This work develops a target detection algorithm based on deep learning technologies, particularly convolutional neural networks and neural network modeling. Building on the analysis of the traditional Haar-like vehicle recognition algorithm, a vehicle recognition algorithm based on a convolutional neural network with fused edge features (FE-CNN) is proposed. The experimental results demonstrate that FE-CNN improves the recognition precision and the model's convergence speed through a simple and effective edge feature fusion method. In the experiment conducted using real traffic scene for vehicle recognition, the developed algorithm achieves a 99.82% recognition rate in efficient time, demonstrating the capability for real-time performance and accurate target detection. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review is to synthesize the findings in the literature on the relative contribution of two types of linguistic knowledge (i. e., vocabulary and grammatical knowledge) to L2 reading comprehension; and to discuss the possible factors that might have led to the complexity and incongruity of the research findings. Nineteen studies were identified for this review through a systematic process of selection, and were analyzed in terms of the relationship of vocabulary and grammatical knowledge with L2 reading comprehension and their relative significance. The result of this review showed that there was no clear evidence supporting which type of linguistic knowledge is more contributive than the other; and the inconclusive findings might be attributed to the variations in the design of the studies. Two factors emerged, including participants' language proficiency and construct definition, operationalization, and measurement. Some considerations for future research are suggested. [ABSTRACT FROM AUTHOR]

• Attention-based local relation learning module can dynamically explore semantic relation in an anisotropic way. • Context-guided aggregation module further enhances the distinguishing ability of points in feature space. • Gated propagation strategy flexibly filters out irrelevant and redundant information between encoder and decoder. • Multi-scale supervision boosts the training process. Semantic segmentation of point cloud is a fundamental problem in scene-level understanding. Despite advancement in recent years by leveraging capabilities of Neural Networks and massive labeling datasets available, providing fine-grained semantic segmentation for point cloud is still challenging, given the fact that point cloud is usually unstructured, unordered and sparse. In this paper, we achieve semantic point cloud labeling by adaptively exploring semantic relation and aggregating contextual information between points. Specifically, we first introduce an attention-based local relation learning module for collecting local features, which can capture semantic relation in a manner of anisotropy. And we then design a novel context aggregation module guided by multi-scale supervision to obtain long-range dependencies between semantically-correlated points and enhance the distinctive ability of points in feature space. In addition, a gated propagation strategy is adopted instead of skip links to conditionally concatenate local point features in different layers. We empirically evaluate our method on public benchmarks (S3DIS and ShapeNetPart), and demonstrate our performance is on par or better than state-of-the-art methods. [ABSTRACT FROM AUTHOR]

In this paper, an extraction algorithm of color disease spot image based on Otsu and watershed is proposed to overcome the problem of excessive segmentation in the traditional watershed algorithm. The proposed algorithm converts the color space of the color spot image to calculate the component gradient that is not interfered by the reflected light in the new color space. Then, final gradient image is obtained from the gradient image reconstructed by open and close operation under the different-sized structural elements. The label from the final gradient image is extracted by Otsu algorithm, and then, the H-minima transform is used to modify the labeled image. The modified gradient image is transformed with a label by the watershed algorithm. Finally, the extraction of the disease spot is implemented. The experimental results show that the proposed approach obtains accurate and continuous target contour and reaches the requirement of human visual characteristics. Compared with other similar algorithms, the proposed algorithm can effectively suppress the impact of reflected light, optimize the extraction results of disease spot, better maintain the information of disease spot image, and improve the robustness and the applicability. [ABSTRACT FROM AUTHOR]

The authors examined the complexity of the simple view of reading, focusing on morphological decoding fluency in fourth‐grade readers of English in Singapore. The participants were three groups of students who all learned to become bilingual and biliterate in the English language (EL) and their respective ethnic language in school but differed in the home language they used. The first group was ethnic Chinese students who used English as the dominant home language (Chinese EL1); the other two groups were ethnic Chinese and Malay students whose dominant home language was not English but Chinese (Chinese EL2) and Malay (Malay EL2), respectively. The measures included pseudoword decoding (phonemic decoding), timed decoding of derivational words (morphological decoding fluency), oral vocabulary, and passage comprehension. Path analysis showed that oral vocabulary significantly predicted reading comprehension across all three groups, yet a significant effect of morphological decoding fluency surfaced in the Chinese EL1 and Malay EL2 groups but not the Chinese EL2 group. Multigroup path analysis and commonality analysis further confirmed that morphological decoding played a larger role in the Chinese EL1 and Malay EL2 groups. These findings are discussed in light of the joint influence of target‐language experience and cross‐linguistic influence on second‐language or bilingual reading development. [ABSTRACT FROM AUTHOR]

La 2 Zr 2 O 7 used as a top coat material has low thermal conductivity and high stability at high temperature, but it also has a low fracture toughness, which limits its application. To improve the fracture toughness of La 2 Zr 2 O 7 , a La 2 Zr 2 O 7 @YSZ core–shell structured composite ceramic was designed and prepared. The morphology of the La 2 Zr 2 O 7 @YSZ composite ceramic was investigated using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The resulting images show that the YSZ is coated on the surface of the La 2 Zr 2 O 7. The phases were analyzed by X-ray diffraction (XRD), and the XRD patterns show that pyrochlore and fluorite structures coexist in the La 2 Zr 2 O 7 @YSZ composite material without any chemical reaction. Differential scanning calorimetry (DSC) was used to detect the heat change of the composite ceramic during heat treatment. The properties of the La 2 Zr 2 O 7 @YSZ composite ceramic, such as the thermal conductivity, coefficient of thermal expansion (CTE), and mechanical properties were investigated using a laser flash method, high-temperature dilatometer, and nano-hardness tests, respectively. The thermal conductivity of the composite ceramic is in the range of 1.7745–2.3076 W m−1 K−1 in the temperature regime of 200–1000 °C. The maximum CTE of the composite ceramic is 10.3 × 10−6/°C. Owing to the thin YSZ coating on the La 2 Zr 2 O 7 surface, the hardness and Young's modulus of the composite ceramic are 8.17 GPa and 168.3 GPa, respectively. The nucleation and propagation of micro-cracks are investigated using a micro-hardness tester. Compared to La 2 Zr 2 O 7 , the micro-cracks in the composite ceramic are shorter and more tortuous. The weak interface between the YSZ and La 2 Zr 2 O 7 results in the nucleation and tortuous propagation of micro-cracks, which depletes part of the energy and improves the fracture toughness of the composite ceramic. The results reveal that the La 2 Zr 2 O 7 @YSZ composite ceramic has good mechanical and thermophysical properties. [ABSTRACT FROM AUTHOR]

In this study, an image representation method based on multi‐scale microstructural binary pattern extraction is proposed, which uses zero‐mean microstructural pattern binarisation. This method can express all kinds of important pattern structures that may appear in the image. By using the dominant binary pattern learning model, the dominant feature pattern sets adapted to different datasets can be obtained, which have good performance in the aspects of feature robustness, recognition, and representation ability. This method can greatly reduce the dimension of feature coding and improve the speed of the algorithm. The experimental results show that this method has strong recognition ability and robustness, is superior to the traditional local binary pattern and grey image micorstructure maximum response pattern methods, and has a competitive performance compared with the results of many latest algorithms. [ABSTRACT FROM AUTHOR]

Based on pairs of spatial symmetric patches, a novel efficient and distinctive binary descriptor is proposed in this paper for rotated circular image recognition. To achieve rotation invariance during feature computation, a local coordinate system is first found with radial transform technology. On the basis of that, local binary patterns against rotation can be extracted. Meanwhile, the circular image is divided into a set of overlapped annular regions, and pairs of patch description are constructed with histogram within the ring. Finally, the rotation-invariant image description can be obtained by concatenating the ring features from inner to outer. The performance of proposed method is tested with three datasets, i.e., the euro coins, QQ expression and car logo. The test results show that its recognition accuracies reach 100, 100 and 97.07%, respectively, which are superior to the results of traditional methods based on LBP feature. And our method presents competitive performance contrasted to recently proposed LBP invariants, i.e., R_LBP, CS_LBP and PRI_COLBP, and conventional floating and binary descriptors, such as SIFT, SURF, BRISK and FREAK. Moreover, the algorithm is efficient, as single-point feature computation needed only 0.045 ms. [ABSTRACT FROM AUTHOR]

Background: While much is known about how morphological awareness (MA) contributes to reading development, little attention has been paid to how reading may conversely affect MA development, particularly in readers of Chinese in a bilingual/multilingual setting. Methods: The study adopted a cross‐lagged panel design. Young bilingual readers of Chinese were measured in MA, word reading and reading comprehension – all in Chinese – twice from Grade 3 to Grade 4. Results: Path analysis revealed that Grade 3 MA significantly predicted Grade 4 reading comprehension after controlling for the autoregressive effect. Over and above Grade 3 MA, Grade 3 reading also significantly predicted Grade 4 MA. Subsequent analyses, however, revealed disparate developmental patterns between those with Chinese and English, respectively, as their home language. Implications: These findings, while supporting reciprocity of developmental relationships between MA and reading, also suggested that the pattern of relationships can vary as a function of students' target language experiences in a bilingual/multilingual setting. Highlights: What is already known about this topic Morphological awareness predicts reading development in monolingual children, including Chinese‐speaking children. What this paper adds Morphological awareness predicts Chinese reading development in bilingual children with English as their primary reading language.There are developmentally reciprocal relationships between morphological awareness and reading abilities in those readers.The relationships vary in students with differential Chinese language experiences. Implications for theory, policy or practice Morphological awareness supports reading development but is also facilitated by reading experiences.Target language experiences moderate patterns of reading development.Morphological instruction may be particularly important for readers who do not speak the target language at home in a bilingual/multilingual setting. [ABSTRACT FROM AUTHOR]

Solution crystallization of TPI is relatively less concerned, though the crystallization kinetics from solution is profoundly related to the advance in fraction purification and the precipitation polymerization of TPI. In this work, isothermal crystallization of TPI from its solutions with varied concentrations and solvents at temperatures ranged from −20 °C to 30 °C were studied to attain the kinetic parameters and crystal forms. The solubility curves of TPI in the solvents and the conversion temperatures between isothermal and non-isothermal crystallization were supplied to propose the available concentrations and temperatures for TPI isothermal crystallization. In most cases, the kinetics of TPI crystallization was subject to the Avrami-equation, revealing as the crystallization rate of TPI increase with TPI concentration but decrease with crystallization temperature ( T c ) though few deviations arising from the influence of non-isothermal crystallization and transient nucleation were also observed under several special conditions. The better quality solvents of TPI, like THF and toluene exhibited the relatively slower crystallization rate. The α form of TPI crystals was found to appear as samples crystalized from heptane and THF. [ABSTRACT FROM AUTHOR]

This study examined the similarities and differences in the functioning of component processes underlying first language (L1) and second language (L2) word reading in Chinese. Fourth-grade Chinese children in Singapore were divided into L1 and L2 reader groups based on whether they used Mandarin or English as their home language. Both groups were administered a battery of tasks that assessed their orthographic processing skill (OP), phonological awareness (PA), morphological awareness (MA), oral vocabulary knowledge, as well as the ability to decode characters and multi-character compound words. Separate Structural Equation Modeling (SEM) analyses showed that in the L1 group, over and above all other variables, both OP and MA, as opposed to PA, were significant predictors of word reading, whereas in the L2 group, OP and PA, as opposed to MA, predicted word reading. Multiple-group SEM analysis further revealed that the effects of OP and MA were significantly larger in the L1 than in the L2 group, whereas a converse pattern was found for PA. These findings are discussed in light of the linguistic and language-to-print mapping properties of Chinese as well as the influence of L1 and L2 learners' differential experience on how they learn to read in Chinese. [ABSTRACT FROM AUTHOR]

In this paper we develop an interactive modeling system for complex geometric details transformation based on empirical mode decomposition (EMD) on multi-scale 3D shapes. Given two models, we aim to transfer geometric details from one model to another one in an interactive manner. Taking full advantages of the multi-scale representation computed via EMD, different-scale geometric details can be transferred individually or in a concerted way, which makes our algorithm much more flexible than cut-and-paste and cloning based methods in transferring geometry details. In this process, the target surface with new transferred details could be generated by a mesh reconstruction method widely used in Laplacian surface editing. With the original positions of target surface serving as the soft constraints, the overall shape of the target model will be fully preserved. Our method can also support real-time continuous details transfer. Compared with state-of-the-art algorithms, our method provides an easier-to-use modeling tool and produces varied modeling results. We demonstrate the effectiveness of our modeling tool with various applications, such as detail transfer and enrichment, model reuse and recreation, and detail recovery for shape completion. [ABSTRACT FROM AUTHOR]

Considering the dual-level representation of meaning in print in Chinese, this study differentiated between morphemic (i.e., morphemic awareness) and sub-morphemic (i.e., graphomorphological awareness) dimensions of morphological awareness and examined their concurrent contributions to text comprehension in fourth grade Chinese readers in a multilingual context where Chinese literacy only has an ancillary function. Structural Equation Modeling analysis revealed that while both dimensions of morphological awareness were significant independent contributors to word reading and vocabulary knowledge, only morphemic awareness significantly predicted text comprehension over and above the two word-level skills. On the other hand, significant indirect effects of both graphomorphological and morphemic awareness were found on text comprehension; in addition, those indirect effects were found to be mediated by vocabulary knowledge or jointly by word reading and vocabulary knowledge. These findings were discussed in light of the centrality of meaning in text comprehension and possible contextual variation in the functioning of different dimensions of morphological awareness in Chinese reading development. [ABSTRACT FROM AUTHOR]

This longitudinal study examined metalinguistic awareness in bilingual word reading development among Malay–English bilingual children in Singapore. Participants were assessed with the same tasks twice with a 1-year interval from Grade 3 to Grade 4 in phonological and morphological awareness and derived word decoding in both English and Malay. Structural equation modeling analyses revealed that both types of metalinguistic awareness significantly predicted derived word reading in both languages. Subsequent cross-lagged panel modeling found construct-level transfer facilitation effect from Malay on English for phonological awareness but conversely from English on Malay for morphological awareness. Neither type of metalinguistic awareness exerted a transfer facilitation effect on word reading. These findings shed light on the developmental mechanism of cross-linguistic transfer in biliteracy acquisition. [ABSTRACT FROM PUBLISHER]

In order to explore a novel material for thermal barrier coatings (TBCs), the composite ceramic materials of lanthanum zirconate (La 2 Zr 2 O 7 ) and lanthanum phosphate (LaPO 4 ) were prepared by calcining. The phases and micro-structures of La 2 Zr 2 O 7 /LaPO 4 composite ceramic materials were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The properties of La 2 Zr 2 O 7 /LaPO 4 material, such as thermal conductivity, coefficient of thermal expansion (CTE) and mechanical properties of La 2 Zr 2 O 7 /LaPO 4 were investigated using laser flash method, high-temperature dilatometer and micro-hardness test. Based on XRD patterns, the pyrochlore and monazite phases were obtained in La 2 Zr 2 O 7 /LaPO 4 composite ceramic material without any chemical reaction. According to SEM morphology, the La 2 Zr 2 O 7 was closely near to LaPO 4 along with a lot of pores, it might cause the decrease of thermal conductivity. The thermal conductivities of composite ceramics were similar to that of La 2 Zr 2 O 7 . The CTE of them were about 10 × 10 − 6 K − 1 , which was close to the value of LaPO 4 . Because of doping LaPO 4 , hardness and Young's modulus of samples were lower than that of La 2 Zr 2 O 7 . The studies revealed that the La 2 Zr 2 O 7 /LaPO 4 composite ceramics had good mechanical and thermal physical properties and could be applied as new candidate materials for TBCs in the future. [ABSTRACT FROM AUTHOR]

This intervention study examined the effect of English morphological instruction on the development of English as well as Malay morphological awareness and word reading abilities among Malay–English bilingual fourth graders in Singapore, where English is the medium of instruction. The intervention group experienced semester-long instruction in English derivation; the control group was taught with their regular English curriculum. Both groups were tested with derivational awareness and derived word decoding tasks in English and Malay at the end of Grade 3 prior to the intervention (pre-test) and at the end of the first semester of Grade 4 right after the intervention (post-test). There was no significant difference between the two groups on all tasks at pre-testing. Significant intervention effects were found on the development of English abilities in that the intervention group's performance gain was significantly greater than that of the control group on all English tasks except the derived decoding fluency task. More important, such intervention effects were also evident with some Malay tasks. These findings provide empirical evidence that supports the benefits of morphological instruction to bilingual children's reading development and a possibly causal effect of cross-linguistic transfer of morphological awareness from English to Malay. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma is one common pediatric malignancy notorious for high temporal and spatial heterogeneities. More than half of its patients develop distant metastases involving vascularized organs, especially the bone marrow. It is thus necessary to have an economical, noninvasive method without much radiation for follow‐ups. Radiomics has been used in many cancers to assist accurate diagnosis but not yet in bone marrow metastasis in neuroblastoma. Methods: A total of 182 patients with neuroblastoma were retrospectively collected and randomly divided into the training and validation sets. Five‐hundred and seventy‐two radiomics features were extracted from magnetic resonance imaging, among which 41 significant ones were selected via T‐test for model development. We attempted 13 machine‐learning algorithms and eventually chose three best‐performed models. The integrative performance evaluations are based on the area under the curves (AUCs), calibration curves, risk deciles plots, and other indexes. Results: Extreme gradient boosting, random forest (RF), and adaptive boosting were the top three to predict bone marrow metastases in neuroblastoma while RF was the most accurate one. Its AUC was 0.90 (0.86–0.93), F1 score was 0.82, sensitivity was 0.76, and negative predictive value was 0.79 in the training set. The values were 0.82 (0.71–0.93), 0.80, 0.75, and 0.92 in the validation set, respectively. Conclusions: Radiomics models are likely to contribute more to metastatic diagnoses and the formulation of personalized healthcare strategies in clinics. It has great potential of being a revolutionary method to replace traditional interventions in the future. [ABSTRACT FROM AUTHOR]

This paper develops a new health assessment method based on belief rule base with sliding time window considering correlation and redundancy of input information (BRB-WCR). The new proposed method aims to solve four problems in health assessment of dynamic complex system: lack of system fault data, uncertainty of expert knowledge, correlation of characteristic and high real-time requirement of system. The traditional BRB model can address the first two problems while it assumes that the input characteristics are completely independent. In order to solve the two remaining problems, a new BRB-WCR model is developed, where the correlation and redundancy of characteristics are considered and the sliding time window for online training data is introduced to improve the real time performance of the model. Moreover, to address the uncertainty of expert knowledge, a new optimization model is developed to train the parameters of the BRB-WCR model. To illustrate the effectiveness of the developed method, a case study of inertial navigation platform is conducted. • A new BRB-WCR model with considering correlation and redundancy of characteristics. • The sliding time window for online training data. • A new health assessment method based on BRB-WCR for dynamic complex system. • Optimization model for sliding time window and model parameters. [ABSTRACT FROM AUTHOR]

S-136 (STAVAX ESR) steel has been widely applied in the mold manufacturing industry. Commercially available S-136 steel possesses high surface roughness, which exerts negative effects on the device performance. In this paper, S-136 steel surface planarization using chemical mechanical polishing (CMP) was investigated and the process parameters included down pressure, platen speed, slurry pH and abrasive category. The results demonstrated that the relationship of material removal rate (MRR) with respect to the multiply of pressure and platen speed was in accordance with a modified Preston equation: MRR = ( KP + B 0 ) V + R 0 . With the variation of pH, the MRR changed rapidly. Compared with initial root mean square (RMS) roughness of 37.47 nm, the ultra-smooth surface with RMS roughness 3.01 nm was obtained under optimized condition with MRR as high as 187 nm/min. Finally, optimized CMP process parameters for S-136 steel were proposed and its CMP mechanism was discussed in detail. [ABSTRACT FROM AUTHOR]

This study examined contribution of morphological awareness to reading comprehension in two typologically diverse languages, focusing on young Chinese EFL (English as a Foreign Language) readers in China. It was particularly interested in how cross-linguistic similarities and variations in morphological awareness affected its transfer in Chinese–English biliteracy acquisition. Grades 5 and 6 children were measured in compound awareness and reading comprehension in English, and compound awareness, radical awareness, and reading comprehension in Chinese. Hierarchical regression analyses revealed that compound awareness contributed to reading comprehension within both Chinese and English. In addition, over and above English compound awareness and Chinese reading comprehension, Chinese compound awareness, but not radical awareness, explained a unique amount of variance in English reading comprehension. After Chinese compound awareness was controlled for, English compound awareness, however, did not make a significant contribution to Chinese reading comprehension. These findings were discussed in light of the common and language/script-dependent aspects of morphological awareness in Chinese and English and the context of biliteracy acquisition. [ABSTRACT FROM AUTHOR]

Abstract: Oxidation behavior of NiCoCrAlY coating on T92 steel was investigated in this study. NiCoCrAlY coating was fabricated on T92 steel by electron beam physical vapor deposition (EB-PVD). Isothermal oxidation test was performed at 650°C for about 300h. X-ray diffraction (XRD) was employed to characterize the phases in the coating. Scanning electron microscopy (SEM) with energy dispersive spectrum (EDS) was adopted to analyze microstructures and element distribution. Micro-hardness test and high temperature erosion wear test were also done for detecting the properties of T92 steel and substrate with NiCoCrAlY coating. The results showed that the oxidation weight gain of T92 steel and substrate with NiCoCrAlY coating were 1.119mg/cm2 and 0.325mg/cm2, respectively. Fe2O3 and Fe3O4 were found on T92 substrate surface, while Al2O3 and Cr2O3 formed on NiCoCrAlY coating surface after oxidation at 650°C. Elements between coating and substrate diffused during oxidation. The wear rates of T92 substrate and coating of high temperature erosion wear test were respectively 27.82mg/cm2 and 1.51mg/cm2. Micro-hardness of T92 steel with coating was about 270HV. Depositing NiCoCrAlY coating on T92 steel can effectively improve the oxidation resistance. [Copyright &y& Elsevier]

This study examines the intra- and inter-lingual relationships between first and second language morphological awareness and reading comprehension among grade 6 Chinese learners of English as a foreign language in China. Morphological awareness measures covered compounding as well as derivation. Hierarchical regression analyses revealed that within both Chinese and English, compound and derivational awareness independently and significantly predicted reading comprehension. Cross-linguistically, Chinese compound awareness explained a unique proportion of variance in English reading comprehension, over and above English vocabulary knowledge, English compound awareness, and other related variables. Such a cross-linguistic effect, however, was not found of English compound awareness on Chinese reading comprehension. Derivational awareness in one language did not show a significant cross-linguistic relationship with reading comprehension in the other language, when other variables were considered. These results are discussed in light of the importance of morphological awareness to reading comprehension, cross-linguistic transfer of morphological awareness and a possible linguistic distance effect on such transfer, and the context of Chinese–English biliteracy acquisition. [ABSTRACT FROM PUBLISHER]

This study examined foreign language learners' morphological awareness and its contribution to reading comprehension, focusing on young Chinese EFL learners. Morphological awareness measures covered inflection, derivation, as well as compounding. Results showed that the learners' basic facet of inflectional awareness was better than that of derivational awareness; their compound awareness was better than derivational awareness, for both basic and refined facets; and the advantage of compound awareness over derivational awareness was smaller for the basic facet than for the refined facet. In addition, derivational and compound awareness independently predicted English reading comprehension, over and above vocabulary and grammatical knowledge. These findings were discussed in light of the joint effects of L2 lexical exposure and first language morphological experience on L2 morphological competence, and the importance of morphological awareness to English reading comprehension. [Copyright &y& Elsevier]

This study examined transfer facilitation effect of first language morphological awareness on second language lexical inference ability among Grade 6 Chinese-speaking English as a foreign language learners in China. A set of paper and pencil tests was administered to measure children's morphological awareness and lexical inference ability in both Chinese and English. Results showed that the contribution of Chinese morphological awareness to English morphological awareness was larger for compound words than for derived words. In addition, the indirect effect of Chinese compound awareness on English compound word meaning inference was significant, but that of Chinese derivational awareness on English derived word meaning inference did not achieve significance. These findings confirmed that cross-linguistic transfer of Chinese morphological awareness was responsive to the linguistic distance between Chinese and English. [ABSTRACT FROM PUBLISHER]

Using structural equation modeling analysis, this study examined the contribution of vocabulary and grammatical knowledge to second language reading comprehension among 190 advanced Chinese English as a foreign language learners. Vocabulary knowledge was measured in both breadth (Vocabulary Levels Test) and depth (Word Associates Test); grammatical measures focused on learners' implicit (timed grammaticality judgment task), as well as explicit knowledge (grammatical error correction task); reading comprehension had three indicators, namely, co-reference, textual inference, and gist. Vocabulary knowledge related significantly to reading comprehension; grammatical knowledge showed a weak contribution to reading comprehension after controlling for the effect of vocabulary knowledge. In addition, learners' implicit knowledge of grammar had a stronger relationship to reading comprehension than explicit knowledge, over and above the effect of vocabulary size. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of La0.85Sr0.15MnO3 (LSM) are deposited on (100) silicon wafer and YSZ (yttria-stabilized zircornia) electrolyte substrates by magnetron sputtering using a single-phase LSM target. The conditions for sputtering are systematically studied, including substrate temperature (from room temperature to 600°C), the argon background pressure (from 1.2×10−2 to 3.0×10−2 mbar), and deposition time. Results show that the optimal conditions for producing a dense, uniform, and crack-free LSM film include a substrate temperature of 600°C and an argon pressure of 1.9×10−2 mbar. Further, a testing cell with a dense LSM film, an YSZ electrolyte membrane, and a porous LSM counter electrode is prepared and the electrochemical properties of the dense LSM film on YSZ substrate are studied. It was found that the thickness, morphology, and microstructure of LSM films critically influence the electrochemical properties. [Copyright &y& Elsevier]

This study examined young Heritage Language (HL) learners' home literacy environment and its impact on HL word-knowledge development, focusing on a group of Chinese-English bilingual children learning to read in Chinese as a Heritage Language in the United States. A home literacy survey revealed that parents mostly used HL to talk to children, while learners preferred to use English or a mixture of English and HL to talk to their parents. Learners' HL reading practice at home showed a schoolwork orientation. There was a significant positive correlation between parents' language use and learners' HL vocabulary breadth; learners' schoolwork-related reading practice was also positively correlated with HL word knowledge. However, no significant relations were observed between independent and shared reading unrelated to schoolwork and learners' word knowledge. These findings are discussed in relation to the importance of school materials in HL literacy development and a possible threshold of frequency of schoolwork-unrelated reading that has to be passed for learners to be benefited. [ABSTRACT FROM AUTHOR]

Abstract: On the basis of fuzzy rough model (FRM), a method to construct rough neural network FRM_RNN_M is proposed. By means of adaptive Gaustafason–Kessel (G–K) clustering algorithm, fuzzy partition can be accomplished in input feature space. Then based on the search of cluster numbers and attribute subsets, optimal FRM model will be found, and by integrating it with neural network technique, FRM_RNN_M is constructed. The experiment results of classifying Brodatz texture image indicate that FRM_RNN_M is superior to traditional Bayesian and learning vector quantization (LVQ) methods, moreover, FRM_RNN_M has more powerful comprehensive soft decision-making ability than single FRM model. Also, experimental results show that it is favorable to obtain better FRM model if the search of reductive attribute subsets is included. Compared with conventional rough logic neural network (RLNN), FRM_RNN_M has superiorities in the size of structure, convergence speed and generalization ability. [Copyright &y& Elsevier]

The human eye has the behavior of fixation shift, which is represented by visual search mechanism. Human visual search mechanism has the characteristics of visual guidance from global to local. In order to imitate this behavior, this paper proposes a novel salient object detection model which integrates global and local perception based on visual search guidance. First, by using multi-level feature complementarity, a coarse global perceptual map can be obtained by encoding VGG network and decoding deconvolution network. Then, through the Maximally Stable External Regions (MSER) algorithm, the local hotspot sub-regions in the coarse global perceptual map are intercepted, and generating a visual guidance search path based on the maximum response principle, and the local fine perceptual map is successively merged through the Squeeze-and-Excitation Networks (SENet) step by step. Finally, the salient map integrating the coarse global and fine local perception is achieved. Because only one local area needs to be integrated at a time, which is equivalent to solving a relatively simple problem at a time, it is easy to get more accurate results. The experimental results show that the time-consuming of our model is relatively low and compared with the classical and more recent SOTA methods, our model also shows competitive results. • A global to local visual perceptual integration model for salient object detection is proposed. • It improves the precision of global coarse sensing through local fine sensing. • This paper realizes the dynamic observation behavior from global to local. • Exhibits excellent performance in salient object detection experiments is achieved. [ABSTRACT FROM AUTHOR]

Abstract: In this study, conventional two-layered TBCs with different bond coat surface roughnesses were produced by EB-PVD on Ni-based superalloy. The thickness of the bond coat and top coat was approximately 60 μm and 120 μm, respectively. Before ceramic deposition, the bond coat surface was blasted by different sizes of Al2O3 grit to form different surface roughnesses, denoted by the values of Ra, of 0.82 μm, 1.57 μm and 3.76 μm, respectively. Thermal cyclic testing was carried out by exposing to air at 1323 K for 0.5 h, and then cooling to room temperature within 5 min by forced air cooling. Rockwell surface indentation and Micro-Knoop cross-section indentation tests were employed to evaluate the adhesion between the bond coat and top coat. The roughness of the bond coat significantly affects the lifetime of TBCs in the presented roughness range. With increasing roughness Ra of the bond coat, the weight gain increased evidently during thermal cycling and the lifetime decreased. The lifetime was 730 hs (1460 cyclic times) for the TBCs with a surface roughness Ra of about 0.82 μm, however, only 530 hs was counted for the TBCs with the surface roughness Ra of 3.76 μm. Rockwell surface indentation and Micro-Knoop indentation tests also showed that the adhesion state between the bond coat and the top coat was affected by the bond coat surface roughness. [Copyright &y& Elsevier]

Abstract: In the present study, thermal barrier coatings (TBCs) with two layered bond coat of MCrAlY and MCrAlY–Si were prepared by means of electron beam physical vapor deposition (EB-PVD) on Ni3Al based alloy IC6 in order to suppress the diffusion of Mo contained in the alloy. For the bond coat without Si addition, Mo content near the surface was higher than 7wt% after isothermal oxidation at 1373K for 60h and 12.5wt% after thermal cycling tested at 1373K for 300h (600 cycles). However, in the two layered bond coat with MCrAlY and MCrAlY–Si, only 0.4wt% Mo was detected after isothermal oxidation at 1373K for 100h and about 0.6wt% after thermal cycling tested at 1373K for 400h (800 cycles). With the use of two layered bond coat of MCrAlY and MCrAlY–Si, the diffusion of Mo was effectively blocked and the thermal cycling behavior of the TBCs has been greatly improved. [Copyright &y& Elsevier]

Ni3Al based alloy IC6, a high performance cast alloy with approximately 14 wt.% Mo addition, has been developed for turbine blades and vanes of advanced aero-engines and other high temperature structural components. However, because of the high Mo content, during high temperature use, Mo will diffuse into the protective coating layer, which will affect the thermal cycling performance directly. In order to block the diffusion and improve the thermal cycling behavior of thermal barrier coatings (TBCs), a Si chemical gradient MCrAlY&z.sbnd;Si bond coat was prepared by changing the Si content from 0.35 wt.% at the interface of substrate and bond coat to almost 0 near to the surface of the bond coat. For comparison, conventional two-layered structural TBCs with MCrAlY as bond coat were also prepared. The fabricated coatings were evaluated for the microstructures and the composition distribution properties, such as thermal stability and resistance to oxidation. For the bond coat without Si addition, Mo content near the surface was higher than 7 wt.% after isothermal oxidation at 1373 K for 60 h and 12.5 wt.% after thermal cycling tested at 1373 K for 300 h (600 cycles). However, in the Si chemical gradient bond coat, only 0.4 wt.% Mo was detectable after isothermal oxidation at 1373 K for 100 h and approximately 0.66 wt.% after thermal cycling tested at 1373 K for 340 h (680 cycles). [Copyright &y& Elsevier]

Conventional two-layered structure thermal barrier coatings (TBCs), graded thermal barrier coatings (GTBCs) and graded thermal barrier coatings with micropores were prepared onto superalloy DZ22 tube by electron beam physical vapor deposition (EB-PVD). Thermal gradient of the TBCs was evaluated by embedding two thermal couples in the surfaces of the tube and the top coat at different surrounding temperatures with and without cooling gas flowing through the tube. The results showed that higher thermal gradient could be achieved for the GTBCs with micropores compared to the two-layered structure TBCs and GTBCs. However, after the samples were heated at 1050°C, the thermal gradient for the GTBCs with or without micropores decreased with the increase of heating time. On the other hand, the thermal gradient for the TBCs increased with the increase of heating time. Cross-section observations by scanning electron microscopy showed that the change in microstructure was the main reason for the change of the thermal gradient. [Copyright &y& Elsevier]