We report here nanotwin-core-shell Ni(core)NiO(shell) spheres of average size 25 nm prepared through polyol method. They exhibit high coercive field at 2 K, sharp peak at approximately 20 K in magnetization curve and magnetization reversal. Interestingly, exchange bias due to antiferromagnetic NiO shell is absent. Among other possibilities, anisotropy variations due to particle size distribution and twinning associated with disorder appear to play an important role. Further, magnetic interactions of twinned bigger spheres, which may also act as superferrimagnetic-like Ni multilayer cores, with superparamagnetic Ni of smaller spheres, might be the additional causes. These nanostructures therefore seem to have potential interest in memory effect.
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http://dx.doi.org/10.1166/jnn.2011.2696 | DOI Listing |
Adv Mater
January 2025
Hunan Key Laboratory of Two-Dimensional Materials, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082, China.
The exchange bias (EB) effect is a fundamental magnetic phenomenon, in which the exchange bias field/coercive field ratio (|H/H|) can improve the stability of spintronic devices. Two-dimensional (2D) magnetic heterostructures have the potential to construct low-power and high-density spintronic devices, while their typically air unstable and |H/H| lesser, limiting the possibility of applications. Here, 2D CrTe nanosheets have been systematically synthesized with an in situ formed ≈2 nm-thick Te doped CrO layer (Te-CrO) on the upper surface by chemical vapor deposition (CVD) method.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Institute of Technology, University of the National Education Commission, Podchorążych 2, 30-084 Kraków, Poland.
In this work, three composite materials based on Terfenol-D and PZT-type material were obtained with a classic sintering method using a combination of 0-3 phases, where the ferroelectric phase was doped PZT material (P) and the magnetic phase was Terfenol-D (T). The percentage of P and T components in the composites was variable, i.e.
View Article and Find Full Text PDFHorm Behav
January 2025
Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, United States of America. Electronic address:
Individual variation in stress coping styles is widespread and consequential to health and fitness. Proactive (bold behavior, low stress reactivity, low cognitive flexibility) and reactive (shy behavior, high stress reactivity, high cognitive flexibility) coping styles are found in many species, but the developmental forces shaping them remain elusive. We examined how social influences, specifically mating interactions, shape the development of adult female coping styles with a manipulative rearing experiment using El Abra swordtails, Xiphophorus nigrensis.
View Article and Find Full Text PDFInt J Law Psychiatry
January 2025
Centre of Mental Health, Bielanski Hospital, Warsaw, Poland.
Background: The Mental Health Act (1994) specifies rules of use for direct coercion in Poland. Coercion in psychiatric wards may improve the safety of patients and surroundings but influences compliance and satisfaction with treatment. Legal (formal) coercion regulated by law isn't the one and only form of coercion used on people with mental disorders.
View Article and Find Full Text PDFEnviron Res
January 2025
State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Kowloon, 999077, China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Kowloon, 999077, China.
Bisphenol A (BPA) is a commonly used endocrine-disrupting chemical found in high levels in wastewater worldwide. Aerobic denitrification is a promising alternative to conventional nitrogen removal processes. However, the effects of BPA on this novel nitrogen removal process have rarely been reported.
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