Integrated Radial-axial Magnetic Bearing with Variable Permanent-Magnet Bias Flux In Situ

Xu Shilei,Li Jiajing,Wang Zhipeng,Sun Jinji,Ren Hongliang 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.4

Bias magnetic fl ux plays a crucial role in the performance of active magnetic bearings. However, the bias fl ux produced by NdFeB or SmCo materials in traditional permanent-magnet (PM) bias bearings cannot be adjusted, resulting in infl exible bearing performance. To improve the controllability of the PM bias fl ux in the integrated radial-axial magnetic bearing (RAMB), this article proposes a new design that uses a low coercivity AlNiCo magnet and equips a magnetization coil. By controlling the current of the magnetization coil, the magnetization state and bias fl ux of the AlNiCo magnet can be adjusted in situ, thereby improving the force characteristics and rotor iron losses of the PM-biased RAMB. The designed RAMB is analyzed and verifi ed by the 3D fi nite element method and the analytical model based on Preisach’s hysteresis theory and magnetic circuit method. The proposed design off ers a new idea for magnetic bearing structure and control.

Sodium aescinate alleviates bone cancer pain in rats by suppressing microglial activation via p38 MAPK/c-Fos signaling

Yang Guang,Li Jiajing,Xu Qian,Xie Huilan,Wang Lijun,Zhang Minhao 대한독성 유전단백체 학회 2022 Molecular & cellular toxicology Vol.18 No.4

Background Bone cancer pain (BCP) severely compromises the life quality of patients with advanced cancer or bone metastases . Objective This study investigates the analgesic effect of sodium aescinate (SA) on BCP, and the underlying mechanisms within the spinal cord (SC) and dorsal root ganglion (DRG). Walker 256 cells were intratibially inoculated into rats to establish a BCP model. 10, 20, and 40 g/L of SA was intrathecally injected, respectively, and then, hyperalgesia and allodynia were evaluated by measuring the paw withdrawal threshold (PWT) and paw withdrawal latency (PWL). The effect of SA on neuroinflammation was observed by detecting the production of the pro-inflammatory cytokines based on RT-qPCR and ELISA. The NF-κB and p38 MAPK/c-Fos signaling was detected by WB analysis. Furthermore, RT-qPCR and WB analyses of Iba-1and CD206 were performed to assess microglial activation. Result The development of hyperalgesia and allodynia, and an increase of pro-inflammatory cytokines production, as well as microglial activation, were observed in the BCP rats. SA (40 g/L) not only relieved the pain-related behaviors induced by BCP but also suppressed the release of pro-inflammatory cytokines and the activation of microglia in the SC and DRG. SA could also inhibit p38 MAPK/c-Fos signaling in both the SC and DRG, which might contribute to the suppression of microglial activation. Conclusion Our findings suggest that SA plays a promising analgesic role in the BCP rats by suppressing infl ammation and microglial activation, and these effects may be associated with the suppression of p38 MAPK/c-Fos signaling.

Numerical Investigation on the Ultimate Compression Behavior of Un-strengthened and CFRP-strengthened Steel Tube with Random Pitting Corrosion Damage

Lu Yao,Shaofeng Zhang,Hang Yu,Jiajing Xu,Xiaojian Cao,Yan Ma 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.11

This paper mainly numerically investigates the ultimate compression strength of un-strengthened and CFRP-strengthened steel tubes with random pitting corrosion damage. First, a developed numerical method for steel tubes with random corroded pits is introduced in detail. The accuracy of a similar numerical method is verified through the corresponding experimental measurement and numerical prediction. Then, the ultimate axial compression behavior of steel tubes with random elliptical corroded pits is numerically investigated. Several influencing factors on the ultimate strength of corroded steel tubes under axial compression load are simulated and compared, including different random distributions, region size of corroded pits, number of pits, and depth of pits. Subsequently, the method for strengthening steel tubes by using CFRPs is studied and conducted on the corroded regions of steel tubes. The reliability of steel tubes strengthened by FRP is validated through experimental and numerical results. Finally, the residual compression performance and progressive damage mechanisms of CFRP-strengthened steel tubes are researched. The different parametric influences on the strengthened performance of FRPs are simulated, including layer direction, number of composite layers, and composite materials. The results demonstrate that FRP can improve the axial compression resistance of corroded steel tubes.

Dihydroartemisinin inhibits HepG2.2.15 proliferation by inducing cellular senescence and autophagy

( Jiang Zou ),( Qiang Ma ),( Ru Sun ),( Jiajing Cai ),( Hebin Liao ),( Lei Xu ),( Jingruo Xia ),( Guangcheng Huang ),( Lihua Yao ),( Yan Cai ),( Xiaowu Zhong ),( Xiaolan Guo ) 생화학분자생물학회 2019 BMB Reports Vol.52 No.8

Dihydroartemisinin (DHA) has been reported to possess anti-cancer activity against many cancers. However, the pharmacologic effect of DHA on HBV-positive hepatocellular carcinoma (HCC) remains unknown. Thus, the objective of the present study was to determine whether DHA could inhibit the proliferation of HepG2.2.15 cells and uncover the underlying mechanisms involved in the effect of DHA on HepG2.2.15 cells. We found that DHA effectively inhibited HepG2.2.15 HCC cell proliferation both in vivo and in vitro. DHA also reduced the migration and tumorigenicity capacity of HepG2.2.15 cells. Regarding the underlying mechanisms, results showed that DHA induced cellular senescence by up-regulating expression levels of proteins such as p-ATM, p-ATR, γ-H₂AX, P53, and P21 involved in DNA damage response. DHA also induced autophagy (green LC3 puncta gathered together and LC3II/LC3I ratio increased through AKT-mTOR pathway suppression). Results also revealed that DHA-induced autophagy was not linked to senescence or cell death. TPP1 (telomere shelterin) overexpression could not rescue DHA-induced anticancer activity (cell proliferation). Moreover, DHA down-regulated TPP1 expression. Gene knockdown of TPP1 caused similar phenotypes and mechanisms as DHA induced phenotypes and mechanisms in HepG2.2.15 cells. These results demonstrate that DHA might inhibit HepG2.2.15 cells proliferation through inducing cellular senescence and autophagy. [BMB Reports 2019; 52(8): 520-525]

Integrating magnetized bentonite and pinecone-like BiOBr/BiOI Step-scheme heterojunctions as novel recyclable photocatalyst for efficient antibiotic degradation

Guofu Huang,Kun Liu,Yaseen Muhammad,Tian Fu,Linxing Wang,Jiajing Nong,Shiqi Xu,Luying Jiang,Zhangfa Tong,Hanbing Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.122 No.-

Utilizing the cost-effective natural clay and surface heterojunction engineering to synergistically constructan efficient heterojunction system and promote the separation of photogenerated charges is anappealing strategy for achieving superior photocatalytic activity. In this study, BiOBr/BiOI step-scheme(S-scheme) heterojunction in-suit grown on magnetized bentonite (MBT) was first engineered via facileand mild coprecipitation coupling microwave solvothermal process. The optimized magnetic bentonite/BiOBr/BiOI (MBT25/BiOBr/BiOI, the mass ratio of MBT to BiOBr/BiOI was 25%) attained the largest reactionrate constant (k = 0.021 min1) in tetracycline (TC) photocatalytic degradation within 80 min visible-lightirradiation. In addition, the reaction rate constant k of MBT25/BiOBr/BiOI for TC degradation was 10.51folds higher than that of pristine BiOI. Significantly, the characterization results demonstrated thatMBT effectively assisted the pinecone-like morphology formation of BiOBr/BiOI and endowed the wonderfulmagnetic-separation ability for MBT25/BiOBr/BiOI. Additionally, MBT ingeniously introduced atthe interface could couple with S-scheme heterojunction between BiOBr and BiOI to synergistically boostthe separation and transfer of photogenerated charges. As expected, superior photochemical propertiesand efficient production of active species over MBT25/BiOBr/BiOI were confirmed. Notably, recyclingexperiments verified the wonderful photocatalytic stability and high recovery efficiency of MBT25/BiOBr/BiOI. Furthermore, the abundant O2and OH active species led to hydroxylation, dealkylation,deamidation and ring opening of TC molecules. A synergistically enhanced mechanism over S-schemeMBT25/BiOBr/BiOI was clarified based on band structure calculations. This study offers an innovative perspectiveto design multifunctional photocatalysts with superior activity by integrating properties of magnetizedclay and S-scheme heterojunction.