EFFECT OF FLASH ANNEALING ON MAGNETIC PROPERTIES OF Fe - BASED NANOCRYSTALLINE ALLOYS

Xiaojun Yu,Baiyun Quan,Guiqin Sun,Kenji Narita 한국자기학회 1995 韓國磁氣學會誌 Vol.5 No.5

A heat-treatment method of pre-annealing and then flash annealing(FA) has been used to improve the soft magnetic properties of nanocrystalline Fe_(76)CuSi₁₃B_(10) and Fe_(74)CuNb₃Si₁₂B_(10) alloys. Outstanding magnetic properties of nanocrystalline Fe_(74)CuNb₃Si₁₂B_(10) alloy were attained by flash-annealing in air after annealed at 500℃ for 0.5hr below the crystallization temperature. The same results were obtained for Fe_(74)CuSi₁₃B_(10) alloy. The measurment of relief of stress and X-ray diffraction were used to analyze the effect of flash-annealing.

A Framework for Ranking of WSNs Performance Based on Cloud Model and Entropy Weight

Xiaojun Yu 보안공학연구지원센터 2014 International Journal of Smart Home Vol.8 No.4

A Proxy-Based Data Security Solution in Mobile Cloud

Xiaojun Yu,Qiaoyan Wen 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.5

This paper proposes a data security solution in mobile cloud, which solves the security issues in the mobile client and cloud. The proposed solution also relieves the performance limitation of mobile client when executing security technologies. The analysis about the security, feasibility, compatibility and expansibility and the experiment suggests the proposed solution is rational.

PTEN mutation predicts unfavorable fertility preserving treatment outcome in the young patients with endometrioid endometrial cancer and atypical hyperplasia

Yu Xue,Youting Dong,Yaochen Lou,Qiaoying Lv,Weiwei Shan,Chao Wang,Xiaojun Chen 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.4

Objective: This study aimed to investigate the impact of molecular classification and PTEN, KRAS and PIK3CA gene mutation on the outcome of fertility-preserving treatment in the patients with endometrioid endometrial cancer (EEC) and endometrial atypical hyperplasia (EAH). Methods: This is a single-center retrospective study. A total of 135 patients with EEC and EAH receiving fertility-preserving treatment and molecular classification were reviewed. The distribution of the four types of molecular classification was described. The impact of non-specific molecular profile (NSMP), mismatch repair-deficiency (MMRd), and PTEN, KRAS and PIK3CA gene mutation on the outcome of fertility-preserving treatment was analyzed. Results: Of the patients analyzed, 86.7% (117/136) were classified as having NSMP; 14 (10.4%), MMRd; 1 (0.7%), POLEmut EAH; and 3 (2.2%), p53abn EEC. The patients having NSMP and MMRd achieved similar 16-, 32-, and 48-week complete response rates. The patients harboring tier I and tier II PTEN mutations (PTENmut-Clin) achieved lower cumulative 32-week CR rates than those with PTEN-others (without PTENmut-Clin) (22/47, 46.8% vs. 50/74, 67.6%; p=0.023; odds ratio=0.422; 95% confidence interval [CI]=0.199–0.896). Insulin-resistance (hazard ratio [HR]=0.435; 95% CI=0.269–0.702; p=0.001) and PTENmut-Clin (HR=0.535; 95% CI=0.324–0.885; p=0.015) were independent negative predictors for lower 32-week CR rates. Conclusion: PTENmut-Clin is an independent risk factor for unfavorable fertility-preserving treatment outcomes in the patients with EEC and EAH. The patients with MMRd receiving fertility-preserving treatment achieved outcomes similar to those of the patients with NSMP. The molecular profiles might guide fertility-preserving treatment in the prognosis and clinical decisions.

Improved dielectric properties and energy density of PVDF composites using PVP engineered BaTiO3 nanoparticles

Xiaojun Zhu,Yu Dai 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.7

This work systematically investigates the effect of modifier polyvinylpyrrolidone (PVP) on the microstructure, dielectric and energy storage properties of BaTiO3/PVDF composites. The results demonstrate that the BaTiO3 nanoparticles modified by PVP are uniformly dispersed in the composites, and the defects including cracks and voids are obviously decreased in contrast to the composites with unmodified BaTiO3 nanoparticles. Due to the enhanced interfacial polarization, the composites with BaTiO3@PVP show improved dielectric properties compared with the composites with unmodified BaTiO3 nanoparticles. For instance, at 1 kHz, the dielectric constant and dielectric loss of the composite with 50 vol% of BaTiO3@PVP nanoparticles are 80.4 and 0.085, while of which the BaTiO3/PVDF are 35 and 0.265, respectively. The discharge energy density of the composites is largely improved with PVP engineered BaTiO3 nanoparticles. The composite with 30 vol% BaTiO3@PVP achieves a discharged energy density of 4.06 J/cc at 240 kV/mm, which is 116% larger than that of pure PVDF (1.88 J/cc). This research provides an effect modifier to prepare high performance dielectric materials.

Calculation of cavitation evolution and associated turbulent kinetic energy transport around a NACA66 hydrofoil

Xiaojun Li,Bowen Li,Benxu Yu,Yun Ren,Bo Chen 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.3

The physical mechanism of flow unsteadiness is one of the key problems in cavitating flow. Significant efforts have been exerted to explain the cavitation-vortex interaction mechanism. As well, the process of kinetic energy transport during the evolution of unsteady cavitating flow must be elucidated. In this work, 2D calculations of cavitating flow around a NACA66 hydrofoil were performed based on the open source software OpenFOAM. The modified shear stress transport k-ω turbulence model, which considers curvature and turbulent eddy viscosity corrections, was employed to close the governing equations. The Schnerr-Sauer cavitation model was adopted to capture the cavitation phase change process. Numerical results showed reasonable consistency with the results of the experiments conducted by Leroux et al. (2004). The results showed that cavitation promotes turbulence intensity and flow unsteadiness around the hydrofoil. During the attached sheet cavity growth stage, high-value regions of turbulent kinetic energy are located substantially at the interface of the cavity, particularly at the rear portion of the cavity region. During the cloud cavity shed-off stage, the cavity begins to break off and the maximum value of turbulent kinetic energy is observed inside the shed cavity. Finally, the influence of cavitation on the turbulence intensity is illustrated using the turbulent kinetic energy transport equation, which shows that the pressure diffusion and turbulent transport terms dominate as cavitation occurs. In addition, cavitation promotes turbulence production and increases dissipation with fluid viscosity and flow unsteadiness. The viscous transport term only acts in the cavitation shedding stage under large-scale vortex shedding. Overall, these findings are of considerable interest in engineering applications.

An Improved PSO Algorithm Based on Mutation Operator and Simulated Annealing

Xiaojun Deng,Zhiqiang Wen,Yu Wang,Pingan Xiang 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.10

Particle swarm optimization (PSO) algorithm is simple stochastic global optimization technique, but it exists unbalanced global and local search ability, slow convergence speed and solving accuracy. An improved simulated annealing (ISAM) algorithm is introduced into the PSO algorithm with crossover and Gauss mutation to propose an improved PSO (ISAMPSO) algorithm based on the mutation operator and simulated annealing in this paper. In the ISAMPSO algorithm, the mutation operator of genetic algorithm is introduced into the SA algorithm as a generation mechanism of new solution in order to propose an improved simulated annealing algorithm with mutation (ISAM). Then the ISAM algorithm is introduced into the PSO algorithm to jump out the local optimum, effectively achieve the global optimum adjust and optimize the population, maintain the diversity of the population, improve the local search ability and convergence speed. Six classical functions are selected to test the performance of the proposed ISAMPSO algorithm. The simulation experiments results show that the proposed ISAMPSO algorithm can effectively overcomes the stagnation phenomenon and enhance the global search ability. The convergence speed and accuracy were better than the PSO algorithm.

Differential Expression of miR-34c and Its Predicted Target Genes in Testicular Tissue at Different Development Stages of Swine

Xiaojun Zhang,Wei Zhao,Chuanmin Li,Haibin Yu,YanYan Qiao,Aonan Li,Chunyan Lu,Zhihui Zhao,Boxing Sun 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.11

To verified the target genes of miR-34c, bioinformatics software was used to predict the targets of miR-34c. Three possible target genes of miR-34c related to spermatogenesis and male reproductive development: zinc finger protein 148 (ZNF148), kruppel-like factor 4 (KLF4), and platelet-derived growth factor receptor alpha (PDGFRA) were predicted. Then, the expression of miR-34c and its target genes were detected in swine testicular tissue at different developmental stages by quantitative polymerase chain reaction. The results suggested that the expression of PDGFRA has the highest negative correlation with miR-34c. Then immunohistochemical staining was done to observe the morphology of swine testicular tissue at 2-days and 3, 4, 5-months of age, which indicated that PDGFRA was mainly expressed in the support cells near the basement membrane during the early development stages of testicular tissue, but that the expression of PDGFRA was gradually reduced in later stages. Therefore, western blot analyzed that the highest expression of PDGFRA was generated in 2-days old testicular tissues and the expression levels reduced at 3 and 4-months old, which correlated with the results of immunohistochemical staining. In conclusion, PDGFRA is a target gene of miR-34c.

Development of a simple nomogram to estimate risk for intraoperative complications before partial nephrectomy based on the Mayo Adhesive Probability score combined with the RENAL nephrometry score

Xiaojun Tan,Dachun Jin,Jian Hu,Weili Zhang,Yu Zhou,Yunxiang Li,Yuanfeng Zhang,Ji Wu 대한비뇨의학회 2021 Investigative and Clinical Urology Vol.62 No.4

Purpose: This study aimed to develop a simple nomogram based on the Mayo Adhesive Probability (MAP) score combined with the RENAL nephrometry score (RNS) to predict intraoperative complications before partial nephrectomy (PN) in Asian populations. Materials and Methods: This study retrospectively collected patients undergoing PN at three medical centers. Each component of the MAP score and the RNS (6 variables) was evaluated to assess its association with intraoperative complications by multivariable logistic regression with backward elimination. Results: A total of 46 cases (7.2%) with intraoperative complications were identified among 637 patients. After backward elimination, three variables, including tumor diameter (4–7 cm vs. ≤4 cm: odds ratio [OR], 4.339; 95% confidence interval [CI], 1.943–9,692; ≥7 cm vs. ≤4 cm: OR, 8.434; 95% CI, 1.225–58.090), nearness to the collecting system (4–7 mm vs. ≥7 mm: OR, 2.988; 95% CI, 1.293–6.907; ≤4 mm vs. ≥7 mm: OR, 21.394; 95% CI, 6.122–74.756), and perirenal fat stranding type (type 1 vs. no stranding: OR, 3.119; 95% CI, 1.079–9.017; type 2 vs. no stranding: OR, 18.722; 95% CI, 6.757–51.868), were retained. The predictive power (measured by area under the curve [AUC]) of the nomogram was observed to be superior to the RNS or MAP score alone (RNS: 0.686, MAP score: 0.729, the nomogram: 0.837), but comparable to their combination (0.813). Conclusions: The simple nomogram contains fewer components than the combination of the RNS and MAP scores yet demonstrates equivalent predictive power for intraoperative complications.

Flexible CNC polishing process and surface integrity of blades

Xiaojun Lin,Dongbo Wu,Xiufeng Shan,Gang Wu,Tong Cui,Yun Zhang,Liangyi Hu,Jie Yu 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.6

The surface integrity of aero-engine blades directly affects its mechanical behavior. To improve the surface integrity and address the problem, that is, the blade is mainly polished manually, a flexible polishing process was proposed and surface integrity was investigated. First, flexible polishing technology and the machine tool that the authors researched and developed were introduced. Second, a polishing experiment was conducted on a TC4 titanium alloy blade. Finally, the surface integrity before and after polishing was measured and the results were compared and analyzed. Results showed that the knife marks, pits, unevenness, and other defects of the blade surface were effectively removed through flexible polishing; the surface residual compressive stress was reduced from 483 MPa to 397 MPa; the surface roughness was reduced to Ra 0.4 μm; the surface micro-hardness increased by 18 HV; and the surface metamorphic layer caused by milling was removed. Flexible polishing effectively improved the surface quality without affecting the depth layer quality of the workpiece.