Effects of Yttrium and Cerium co-substitution on Structures and Magnetic Properties of Nanocrystalline Nd-Fe-B Magnets

Xiaoqiang Yu,Lei He,Yuting Hu,Jiajie Li,Xiao Liu,Yuhan Wang,Chunji Li,Munan Yang,Zhenchen Zhong 한국자기학회 2022 Journal of Magnetics Vol.27 No.2

Cerium-containing (Ce) rare earth magnets with extraordinary cost-effectiveness are widely investigated around the world. However, when the concentration of Ce is much more, the kind of these magnets exhibits very poor thermal stability and overall magnetic properties. To weaken these disadvantages, we take eutectic Y50Ce50 co-substitution alloys into account in this work. Magnetic properties, microstructures and metallurgical behaviors of (Y, Ce, Nd)-Fe-B magnets are systematically researched. For (Y50Ce50)10Nd20Fe68.9B1.1 SPSed permanent magnets, good overall magnetic properties are Hcj = 725 kA/m, Jr = 0.73 T and (BH)max = 81 kJ/m³. It schematically depicts that coarse grain zones and fine grain zones occur during the spark plasma sintering (SPS) process. With the Nd content increasing, the deleterious CeFe₂ phases disappear. In addition, the volume fraction and width of coarse grain zones decrease. Ce-rich and Ce-lean regions are also observed in main phases, while Y and Nd elements are uniformly distributed. TEM results show that Nd and Ce are rich in the grain boundary and Y elements prefer to enter in 2:14:1 main phases. This work is favorable to a balanced utilization of high abundance rare earth elements in Nd-Fe-B magnets.

Effects of Starvation on Lipid Metabolism and Gluconeogenesis in Yak

Yu, Xiaoqiang,Peng, Quanhui,Luo, Xiaolin,An, Tianwu,Guan, Jiuqiang,Wang, Zhisheng Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.11

This research was conducted to investigate the physiological consequences of undernourished yak. Twelve Maiwa yak ($110.3{\pm}5.85kg$) were randomly divided into two groups (baseline and starvation group). The yak of baseline group were slaughtered at day 0, while the other group of yak were kept in shed without feed but allowed free access to water, salt and free movement for 9 days. Blood samples of the starvation group were collected on day 0, 1, 2, 3, 5, 7, 9 and the starved yak were slaughtered after the final blood sample collection. The liver and muscle glycogen of the starvation group decreased (p<0.01), and the lipid content also decreased while the content of moisture and ash increased (p<0.05) both in Longissimus dorsi and liver compared with the baseline group. The plasma insulin and glucose of the starved yak decreased at first and then kept stable but at a relatively lower level during the following days (p<0.01). On the contrary, the non-esterified fatty acids was increased (p<0.01). Beyond our expectation, the ketone bodies of ${\beta}$-hydroxybutyric acid and acetoacetic acid decreased with prolonged starvation (p<0.01). Furthermore, the mRNA expression of lipogenetic enzyme fatty acid synthase and lipoprotein lipase in subcutaneous adipose tissue of starved yak were down-regulated (p<0.01), whereas the mRNA expression of lipolytic enzyme carnitine palmitoyltransferase-1 and hormone sensitive lipase were up-regulated (p<0.01) after 9 days of starvation. The phosphoenolpyruvate carboxykinase and pyruvate carboxylase, responsible for hepatic gluconeogenesis were up-regulated (p<0.01). It was concluded that yak derive energy by gluconeogenesis promotion and fat storage mobilization during starvation but without ketone body accumulation in the plasma.

<i>In vivo</i> near-infrared imaging and phototherapy of tumors using a cathepsin B-activated fluorescent probe

Chen, Xiaoqiang,Lee, Dayoung,Yu, Sungsook,Kim, Gyoungmi,Lee, Songyi,Cho, Yejin,Jeong, Haengdueng,Nam, Ki Taek,Yoon, Juyoung Elsevier 2017 Biomaterials Vol.122 No.-

<P><B>Abstract</B></P> <P>The development of multifunctional reagents for simultaneous specific near-infrared (NIR) imaging and phototherapy of tumors is of great significance. This work describes the design of a cathepsin B-activated fluorescent probe (<B>CyA-P-CyB</B>) and its applications as an NIR imaging probe for tumor cells and as a phototherapy reagent for tumors. <I>In vitro</I> experiments demonstrated that <B>CyA-P-CyB</B> was activated via the cleavage of a peptide linker by cathepsin B in tumor cells to produce fluorescence in the NIR region based on a FRET mechanism. MTT assays showed that the phototoxicity of <B>CyA-P-CyB</B> toward cells depended on the activity of cathepsin B, and the probe exhibited specific phototoxicity toward tumor cells. <B>CyA-P-CyB</B> was also successfully applied to the <I>in vivo</I> imaging and phototherapy of tumors. Histological analysis indicated that <B>CyA-P-CyB</B> had no cytotoxic effects on seven mouse tissues (lung, liver, heart, kidney, pancreas, spleen and brain) after the <B>CyA-P-CyB</B> treatment and laser irradiation.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Improvement of OPW-TR Algorithm for Compressing GPS Trajectory Data

Meng, Qingbin,Yu, Xiaoqiang,Yao, Chunlong,Li, Xu,Li, Peng,Zhao, Xin Korea Information Processing Society 2017 Journal of information processing systems Vol.13 No.3

Massive volumes of GPS trajectory data bring challenges to storage and processing. These issues can be addressed by compression algorithm which can reduce the size of the trajectory data. A key requirement for GPS trajectory compression algorithm is to reduce the size of the trajectory data while minimizing the loss of information. Synchronized Euclidean distance (SED) as an important error measure is adopted by most of the existing algorithms. In order to further reduce the SED error, an improved algorithm for open window time ratio (OPW-TR) called local optimum open window time ratio (LO-OPW-TR) is proposed. In order to make SED error smaller, the anchor points are selected by calculating point's accumulated synchronized Euclidean distance (ASED). A variety of error metrics are used for the algorithm evaluation. The experimental results show that the errors of our algorithm are smaller than the existing algorithms in terms of SED and speed errors under the same compression ratio.

A Fast Voxel-based Method for Outlier Removal in Laser Measurement

Hao Chen,Yu Chen,Xu Zhang,Baiyuan Li,Xiaoqiang Liu,Xuefei Shi,Jie Shen 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.6

Discrete data points are noncontinuous without structural information. In this paper, we propose a new fast outlier removal method via voxel-based surface propagation. The main technical components of our approach include (a) an efficient and simple spatial partitioning scheme and (b) a specially-designed surface propagation method. Numerical analyses indicate that our method is about 10 times faster than an existing method and significantly better than other two methods in terms of denoising accuracy. This provides an efficient solution to handling noisy laser-scanning data.

Improvement of OPW-TR Algorithm for Compressing GPS Trajectory Data

( Qingbin Meng ),( Xiaoqiang Yu ),( Chunlong Yao ),( Xu Li ),( Peng Li ),( Xin Zhao ) 한국정보처리학회 2017 Journal of information processing systems Vol.13 No.3

Massive volumes of GPS trajectory data bring challenges to storage and processing. These issues can be addressed by compression algorithm which can reduce the size of the trajectory data. A key requirement for GPS trajectory compression algorithm is to reduce the size of the trajectory data while minimizing the loss of information. Synchronized Euclidean distance (SED) as an important error measure is adopted by most of the existing algorithms. In order to further reduce the SED error, an improved algorithm for open window time ratio (OPW-TR) called local optimum open window time ratio (LO-OPW-TR) is proposed. In order to make SED error smaller, the anchor points are selected by calculating point`s accumulated synchronized Euclidean distance (ASED). A variety of error metrics are used for the algorithm evaluation. The experimental results show that the errors of our algorithm are smaller than the existing algorithms in terms of SED and speed errors under the same compression ratio.

A Text Similarity Measurement Method Based on Singular Value Decomposition and Semantic Relevance

Li, Xu,Yao, Chunlong,Fan, Fenglong,Yu, Xiaoqiang Korea Information Processing Society 2017 Journal of information processing systems Vol.13 No.4

The traditional text similarity measurement methods based on word frequency vector ignore the semantic relationships between words, which has become the obstacle to text similarity calculation, together with the high-dimensionality and sparsity of document vector. To address the problems, the improved singular value decomposition is used to reduce dimensionality and remove noises of the text representation model. The optimal number of singular values is analyzed and the semantic relevance between words can be calculated in constructed semantic space. An inverted index construction algorithm and the similarity definitions between vectors are proposed to calculate the similarity between two documents on the semantic level. The experimental results on benchmark corpus demonstrate that the proposed method promotes the evaluation metrics of F-measure.

A Text Similarity Measurement Method Based on Singular Value Decomposition and Semantic Relevance

( Xu Li ),( Chunlong Yao ),( Fenglong Fan ),( Xiaoqiang Yu ) 한국정보처리학회 2017 Journal of information processing systems Vol.13 No.4

The traditional text similarity measurement methods based on word frequency vector ignore the semantic relationships between words, which has become the obstacle to text similarity calculation, together with the high-dimensionality and sparsity of document vector. To address the problems, the improved singular value decomposition is used to reduce dimensionality and remove noises of the text representation model. The optimal number of singular values is analyzed and the semantic relevance between words can be calculated in constructed semantic space. An inverted index construction algorithm and the similarity definitions between vectors are proposed to calculate the similarity between two documents on the semantic level. The experimental results on benchmark corpus demonstrate that the proposed method promotes the evaluation metrics of F-measure.

Coupled irradiation-thermal-mechanical analysis of the solid-state core in a heat pipe cooled reactor

Yugao Ma,Jiusong Liu,Hongxing Yu,Changqing Tian,Shanfang Huang,Jian Deng,Xiaoming Chai,Yu Liu,Xiaoqiang He 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.6

The solid-state core of a heat pipe cooled reactor operates at high temperatures over 1000 K withthermal and irradiation-induced expansion during burnup. The expansion changes the gap thicknessbetween the solid components and the material properties, and may even cause the gap closure, whichthen significantly influences the thermal and mechanical characteristics of the reactor core. This studydeveloped an irradiation behavior model for HPRTRAN, a heat pipe reactor system analysis code, tointroduce the irradiation effects such as swelling and creep. The megawatt heat pipe reactor MegaPowerwas chosen as an application case. The coupled irradiation-thermal-mechanical model was developed tosimulate the irradiation effects on the heat transfer and stresses of the whole reactor core. The resultsshow that the irradiation deformation effect is significant, with the irradiation-induced strains up to2.82% for fuel and 0.30% for monolith at the end of the reactor lifetime. The peak temperatures during thelifetime are 1027:3 K for the fuel and 956:2 K for monolith. The gap closure enhances the heat transferbut caused high stresses exceeding the yield strength in the monolith

Identification of Saccharum CaM gene family and function characterization of ScCaM1 during cold and oxidant exposure in Pichia pastoris

Wang Hengbo,Feng Meichang,Zhong Xiaoqiang,Yu Qing,Que Youxiong,Xu Liping,Guo Jinlong 한국유전학회 2023 Genes & Genomics Vol.45 No.1

Background Calmodulin (CaM) plays an essential role in binding calcium ions and mediating the interpretation of Ca2+ signals in plants under various stresses. However, the evolutionary relationship of CaM family proteins in Saccharum has not been elucidated. Objective To deduce and explore the evolution and function of Saccharum CaM family. Methods A total of 104 typical CaMs were obtained from Saccharum spontaneum and other 18 plant species. The molecular characteristics and evolution of those CaM proteins were analyzed. A typical CaM gene, ScCaM1, was subsequently cloned from sugarcane (Saccharum spp. hybrid). Its expression patterns in different tissues and under various abiotic stresses were assessed by quantitative real-time PCR. Then the green fluorescent protein was used to determine the subcellular localization of ScCaM1. Finally, the function of ScCaM1 was evaluated via heterologous yeast expression systems. Results Three typical CaM members (SsCaM1, SsCaM2, and SsCaM3) were identified from the S. spontaneum genome database. CaMs were originated from the two last common ancestors before the origin of angiosperms. The number of CaM family members did not correlate to the genome size but correlated with allopolyploidization events. The ScCaM1 was more highly expressed in buds and roots than in other tissues. The expression patterns of ScCaM1 suggested that it was involved in responses to various abiotic stresses in sugarcane via different hormonal signaling pathways. Noteworthily, its expression levels appeared relatively stable during the cold exposure in the cold-tolerant variety but significantly suppressed in the cold-susceptible variety. Moreover, the recombinant yeast (Pichia pastoris) overexpressing ScCaM1 grew better than the wild-type yeast strain under cold and oxidative stresses. It was revealed that the ScCaM1 played a positive role in reactive oxygen species scavenging and conferred enhanced cold and oxidative stress tolerance to cells. Conclusion This study provided comprehensive information on the CaM gene family in Saccharum and would facilitate further investigation of their functional characterization.