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171.
Yusuf Yüksel 《Physics letters. A》2018,382(19):1298-1304
We propose an atomistic model and present Monte Carlo simulation results regarding the influence of FM/AF interface structure on the hysteresis mechanism and exchange bias behavior for a spin valve type FM/FM/AF magnetic junction. We simulate perfectly flat and roughened interface structures both with uncompensated interfacial AF moments. In order to simulate rough interface effect, we introduce the concept of random exchange anisotropy field induced at the interface, and acting on the interface AF spins. Our results yield that different types of the random field distributions of anisotropy field may lead to different behavior of exchange bias. 相似文献
172.
通过Ansoft Maxwell有限元分析软件,用封闭圆桶模型对ITER送气系统阀门箱的磁屏蔽进行了计算。计算,获得了屏蔽层厚度、上端开孔及侧面狭缝对磁屏蔽的影响方式及规律,给出了一种具有合理参数的可能设计。 相似文献
173.
XiaoLi Tang Huai-Wu Zhang Hua Su Yu-Lan Jing Zhi-Yong Zhong 《Journal of magnetism and magnetic materials》2009,321(12):1851-1855
A spin-polarized current changes the strength and direction of the exchange bias in spin valves with a current-in-plane geometry. The exchange bias can be manipulated and systematically changed by applying current pulses. The changes are nonmonotonic and asymmetric with respect to the directions of the applied field and current pulses. For different current pulses, different exchange-bias fields can be achieved in the same sample. Furthermore, for samples with different exchange bias, the bias field exhibits a dependence on the applied pulse. Since the strength of exchange bias is highly correlated to the micromagnetic state distribution of the antiferromagnet, we explain our observations by the spin torque exerted on the interfacial antiferromagnetic moments, excluding Joule heating and training effects. 相似文献
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Akihiro SAKUYAMA Masakazu SAITOH Keigo IWAI Kazuki KON Kentaro HORI Masatoshi NAGAYAMA 《Physical Therapy Research》2021,24(2):128
Objective: This study aimed to determine whether the psoas muscle volume (PMV) and its muscle attenuation (MA) are associated with hospital readmission after transcatheter aortic valve implantation (TAVI). Method: We included 113 older patients with aortic stenosis who underwent TAVI at Sakakibara Heart Institute (mean age 85 ± 5 years, 69% women). We measured PMV and psoas muscle area (PMA) as well as total muscle area (TMA) at the third lumbar vertebra using preoperative computed tomography (CT) images. The crude values of the PMV, PMA, and TMA were normalized by dividing by height squared. Results: The median follow-up period was 724 days (interquartile range: 528-730 days), and there were 25 all-cause readmissions during the follow-up period (22% of all patients). In the multivariate Cox regression analysis adjusted for age, sex, and EuroSCORE II, the PMV and its MA and crude PMA were significantly associated with all-cause readmission [HR: 0.957 (0.930-0.985), p = 0.003, HR: 0.927 (0.862-0.997), p = 0.040], whereas the PMA and TMA and each MA were not (all p > 0.05). The groups with low PMV and MA had significantly higher incidences of all-cause readmission than that with high PMV and MA (log-rank test: p = 0.011). Conclusion: PMV and its MA measured from preoperative CT images were independent predictors of all-cause readmission in TAVI patients. 相似文献
179.
本文介绍了一种新型空间光调制器——硅基底液晶光阀。阐述了该器件的工作原理和各膜层的制备过程。最后提出了两种薄双面抛光片的方法,它们是实现该器件实用化的关键工艺。 相似文献
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