Structural, magnetic and dielectric properties of (Li1+, Al3+) co-doped Ni0.5Zn0.5Fe2O4 ferrite ceramics prepared by the sol-gel auto-combustion method

Qing Ni,Li Sun,Ensi Cao,Wentao Hao,Yongjia Zhang,Lin Ju 한국물리학회 2020 Current Applied Physics Vol.20 No.9

(Li1+, Al3+) co-doped Ni0.5Zn0.5Fe2O4 ferrites, Ni0.5-xZn0.5-xLixAlxFe2O4 (x = 0.000, 0.025, 0.050 and 0.100), were synthesized by the sol-gel auto-combustion method. X-ray diffraction (XRD), field emission scanning electronic microscope (FESEM), vibrating sample magnetometer (VSM) and LCR meter were used to investigate the structural, magnetic and dielectric properties. Results of XRD and SEM indicate that both doping amount and calcination temperature play significant roles in crystal structure and grain growth. Also, it can be observed that the saturation magnetization and the coercivity change in a noticeable manner. The Ni0.475Zn0.475Li0.025Al0.025Fe2O4 ferrite sintered at 1200 °C has a relatively low coercivity value (62.93 Oe) and the largest saturation magnetization (110.95 emu/g). Besides, dielectric behavior is also improved by Li1+ and Al3+ co-doping

Effect of Initial Microstructure on the Hot Deformation Behavior and Microstructure Evolution of Aluminum Alloy AA2060

Chaoyang Li,Guangjie Huang,Lingfei Cao,Ruoxi Zhang,Yu Cao,Bin Liao,Lin Lin 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The microstructure evolution and hot deformation behavior of a Li-containing aluminum alloy AA2060 with different initialmicrostructure (homogenized vs. pre-rolled) were studied by isothermal hot deformation. The tests were performed within awide range of deformation temperatures of 370–490 ℃ and strain rates of 0.01–10 s−1. Results show that the stress drop ratioof the pre-rolled specimen is higher than that of the homogenized one under the same deformation condition. Microstructurewere analyzed on the thermal processing maps in unstable and optimum processing domain, and a higher dynamic recrystallizationfraction can be observed in the pre-rolled specimen that has more substructures and smaller grains. Four typesof the dynamic recrystallization were observed and the mechanism for deformation softening was discussed in this work.

A Novel Distributed Equivalent Circuit Model for Single-Core Cables

Li Rui-Fang,Hu Hao,Cao Xiao-Bin,Li Zhong-Mei,Li Jun-Hao,Zhu Chuan-Lin,Liu Le-Jia 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.1

The number of cables used for urban power supply increases rapidly. The sheath current in these cables, which is generated via induction, produces a current loss. When the situation is serious, the ground lead and the middle connector of the cable will be burned. In this paper, the existing single-core cable equivalent circuit model is used to calculate the sheath current of a 3-phase cable under the condition of non-transposition and cross connection. By comparing the calculated results with the simulation and the experimental results, it is found that the current distribution law for the sheath, which was obtained using the existing model, difers substantially from both the simulation and actual measurements. The error reason of the existing model is revealed, and it is found that the magnitude and phase of the current in the metal sheath of the cable varies with the position under the combined efect of distributed capacitances in the cable and the core-current fux, especially for a 3-phase cross connection, each section of the cable does not meet Kirchhof’s laws, but the sheath electric current in the existing models are considered equal everywhere. Therefore, a novel cable equivalent model is proposed in this paper, which is based on a distributed circuit, and an equation to calculate the sheath current is derived. The model presented in this paper corrects the problems of the existing model, which can be applied to power system, subway, high-speed rail, and any application of single-core cables.

Experimental and Numerical Study on Flexural Performance of a Novel Steel-Encased Concrete Composite Beam

Li-Lin Cao,Ye-Jun Li,Manicka Dhanasekar,Chun-Hua Lu 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.5

This paper presents a novel configuration of high strength U-shaped steel-encased concrete composite beam (HUCB) in which shear studs connect concrete and U-shaped steel at top flanges and bottom plate. The junction surface of upper slab and lower portion is strengthened by evenly distributed inserted circular rebar. Two steel reinforcements are arranged in the composite beam along the longitudinal direction to reduce the deformation of encased concrete and provide adequate bending capacity under fire condition. Based on the flexural experiments of five specimens, the test failure pattern, load-deflection relation curves, sectional strain distribution at different height and ultimate flexural performance of the HUCB were obtained and are reported in this research. The experimental results show that the HUCB has high ductility and excellent flexural performance. According to test results of five specimens, new calculation formulae were presented to theoretically analyze the flexural capacity of the HUCB. The theoretical analysis values of flexural capacity according to the proposed calculation formulae are consistent with the test results of all specimens. A three-dimensional finite element model is also established to investigate structural performance of the proposed novel composite beam. Test results of five specimens verify the accuracy and validity of finite element analysis results. Parametric studies of the HUCB under positive bending moment are carried out to further analyse the influence of concrete compressive strength, yield strength of U-shaped steel plate and flange width of concrete slab on the flexural performance of the proposed new composite beam.

Crystallization and melting behavior of polypropylene in b-PP/polyamide 6 blends containing PP-g-MA

Zhidan Lin,Zixian Guan,Baofeng Xu,Chao Chen,Guangheng Guo,Jiaxian Zhou,Jiaming Xian,Lin Cao,Yueliang Wang,Mingqing Li,Wei Li 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.2

In this research, we used a twin-screw extruder to melt and blend PP-g-MA compatibilizer with bpolypropylene (PP)/polyamide 6 (PA6). The influences of the PA6 and PP-g-MA contents in PP/PA6 blends on crystallization and melting behavior of PP phase and morphology were investigated. The results showed that, when PP-g-MA copolymer was added to the b form of nucleated PP/PA6 blends, the anhydride groups in PP-g-MA and PA6 terminal amine groups react to form PP-g-PA graft copolymer in a two-phase interface. This reduces the interfacial tension, improves the interfacial adhesion, and reduces the size of PA6 domains in the blend. The generated PP-g-PA graft copolymer wrapped PA6 phase and buried the anhydride groups of PP-g-MA. When the proportion of PP-g-MA and PA6 was between 0.5 and 0.75, there was no longer interfering to the formation of b-crystals in the PP phase. The content of bcrystal of PP phase in blends was found to reach as large as 85.9%.

Efficacy and Safety of Thermal Ablation for Solitary Low-Risk T2N0M0 Papillary Thyroid Carcinoma

Fei Yu-Lin,Wei Ying,Zhao Zhen-Long,Peng Li-Li,Li Yan,Cao Shi-Liang,Wu Jie,Zhou Hui-Di,Yu Ming-An 대한영상의학회 2024 Korean Journal of Radiology Vol.25 No.8

Objective: To evaluate the efficacy and safety of thermal ablation in treating solitary low-risk T2N0M0 papillary thyroid cancer (PTC) and compare the outcomes of microwave ablation (MWA) and radiofrequency ablation (RFA). Materials and Methods: This retrospective, single center study involved 34 patients (age: 40.0 ± 13.9 years; 28 female) who had low-risk T2N0M0 PTC with a maximum diameter >2 cm and ≤4 cm and underwent MWA (n = 15) or RFA (n = 19) from November 2016 to April 2023. The primary outcomes were the cumulative rate of disease progression and delayed surgery rates. In contrast, the secondary outcomes included changes in tumor size, cumulative rate of complete tumor disappearance, and complication rates. Results: The median follow-up period was 18.0 months (interquartile range [IQR]: 9.0–40.0 months). At 12 months, the median volume reduction rate of the ablation zone was 74.2% (IQR: 53.7%–86.0%). Disease progression was noted in two patients within 1 year, including one patient with local tumor progression post-RFA and one with a new tumor post-MWA, resulting in a constant cumulative disease progression rate of 8.8% (95% confidence interval [CI]: 0%–19.8%) throughout the remaining follow-up period. Both patients were subsequently treated with additional ablation and did not require surgery. The cumulative rates of complete tumor disappearance at 1, 3, and 5 years were 4.0% (95% CI: 0%–11.4%), 26.8% (95% CI: 2.7%– 44.9%), and 51.2% (95% CI: 0%–79.1%), respectively. No significant differences were observed in the disease progression (P = 0.829) or complete tumor disappearance (P = 0.633) rates between the MWA and RFA groups. Complications occurred in 14.7% (5/34) of patients presenting with transient hoarseness. RFA had a higher but not statistically significant complication rate than MWA did (21.1% [4/19] vs. 6.7% [1/15]; P = 0.355). Conclusion: Both MWA and RFA demonstrated promising short-term outcomes in terms of efficacy and safety in treating solitary low-risk T2N0M0 PTC, with no significant differences.

The Yin-Yang of DNA Damage Response: Roles in Tumorigenesis and Cellular Senescence

Li, Xiaoman,Xu, Hongde,Xu, Chongan,Lin, Meina,Song, Xiaoyu,Yi, Fei,Feng, Yanling,Coughlan, Kathleen A.,Cho, William Chi-shing,Kim, Sang Soo,Cao, Liu MDPI 2013 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.14 No.2

<P>Senescent cells are relatively stable, lacking proliferation capacity yet retaining metabolic activity. In contrast, cancer cells are rather invasive and devastating, with uncontrolled proliferative capacity and resistance to cell death signals. Although tumorigenesis and cellular senescence are seemingly opposite pathological events, they are actually driven by a unified mechanism: DNA damage. Integrity of the DNA damage response (DDR) network can impose a tumorigenesis barrier by navigating abnormal cells to cellular senescence. Compromise of DDR, possibly due to the inactivation of DDR components, may prevent cellular senescence but at the expense of tumor formation. Here we provide an overview of the fundamental role of DDR in tumorigenesis and cellular senescence, under the light of the Yin-Yang concept of Chinese philosophy. Emphasis is placed on discussing DDR outcome in the light of <I>in vivo</I> models. This information is critical as it can help make better decisions for clinical treatments of cancer patients.</P>

Effects of stocking density on the homeostasis of uric acid and related liver and kidney functions in ducks

Lin Peiyi,Liufu Sui,Wang Jinhui,Hou Zhangpeng,Liang Yu,Wang Haiyue,Li Bingxin,Cao Nan,Liu Wenjun,Huang Yunmao,Tian Yunbo,Xu Danning,Li Xiujin,Fu Xinliang 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.5

Objective: Stocking density (SD) is an important issue in the poultry industry, which is related to the production performance, intestinal health and immune status. In the present study, the effects of SD on the metabolism and homeostasis of uric acid as well as the related functions of the liver and kidney in ducks were examined. Methods: A total of 360 healthy 56-day-old Shan-ma ducks were randomly divided into the low stocking density (n = 60, density = 5 birds/m2 ), medium stocking density (n = 120, density = 10 birds/m2 ) and high stocking density groups (HSD; n = 180, density = 15 birds/m2 ). Samples were collected in the 3rd, 6th, and 9th weeks of the experiment for analysis. Results: The serum levels of uric acid, lipopolysaccharide and inflammatory cytokines (interleukin-1β [IL-1β], IL-8, and tumor necrosis factor-α [TNF-α]) were increased significantly in the HSD group. Serious histopathological lesions could be seen in both the livers and kidneys in the HSD group in the 9th week. The mRNA expression levels of inflammatory cytokines (IL-8 and TNF-α) and related pathway components (toll-like receptor 4, myeloid differentiation primary response gene 88, and nuclear factor-κB) were increased significantly in both the livers and kidneys in the HSD group. The mRNA expression levels of enzymes (adenosine deaminase, xanthine oxidase, phosphoribosyl pyrophosphate amidotransferase, and phosphoribosyl pyrophosphate synthetase 1) related to the synthesis of uric acid increased significantly in the livers in the HSD group. However, the mRNA expression level of solute carrier family 2 member 9, which plays an important role in the excretion of uric acid by the kidney, was decreased significantly in the kidneys in the HSD group. Conclusion: These results indicated that a higher SD could cause tissue inflammatory lesions in the liver and kidney and subsequently affect the metabolism and homeostasis of uric acid, and is helpful for guiding decisions related to the breeding and production of ducks.

Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity

Fuli Li,Yufeng Cao,Tingwu Liu,Guilong Yan,Liang Chen,Lilian Ji,Lun Wang,Bin Chen,Aftab Yaseen,Ashfaq A. Khan,Guo-Lin Zhang,Yunyao Jiang,Jianxun Liu,Gongcheng Wang,Ming-Kui Wang,Weicheng Hu 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.4

Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositionsof the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years,the aerial parts of members of the Panax genus have received great attention fromnatural product chemistsas producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation ofnovel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, andtheir structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry,as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated onlipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside LS1 (1) and 5,6-didehydroginsenoside Rg3 (2), were isolated from the leaves of P. ginseng. The isolated compounds 1and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7cells, and Compound 2 showed a significant inhibitory effect with IC50 of 37.38 mM compared with that ofNG-monomethyl-L-arginine (IC50 ¼ 90.76 mM). Moreover, Compound 2 significantly decreased secretionof cytokines such as prostaglandin E2 and tumor necrosis factor-a. In addition, Compound 2 significantlysuppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These resultssuggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food,and the mechanism is warranted for further exploration.

An Optimized Method of Translating SQL to More Efficient Map-reduce Tasks

Jin Cao,Honglin Han,Mingming Zhao,Sijing Ye,Dehai Zhu,Lin Li 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.4