通过随机朗格温模型对磁纳米粒子属性的数据驱动和物理信息估计
Ebrahim Azizi1, Hanlei Wang2, Hansong Zuo3
1Texas Tech University, Lubbock, TX 79409, United States, Lubbock, Texas, 79409, United States.
Nanotechnology
|March 6, 2026
概括
这项研究引入了一种新的随机朗格温模型,以准确地确定来自交流歇斯底里循环数据的磁纳米粒子特性,如和磁化和异性质. 该模型增强了对磁纳米粒子动态的理解.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 磁力学 磁力学 是一种
背景情况:
- 磁纳米粒子 (MNPs) 中的动态磁化由内尔和布朗的放松控制,受内在性质的影响.
- 从集成交流磁化数据中提取精确的MNP参数是具有挑战性的,因为实验限制和模型简化.
研究的目的:
- 开发和验证一个随机朗格温模型来模拟在实验性交流场条件下的MNP磁化歇斯底里.
- 通过将模型与实验数据相匹配,准确估计MNP的关键磁性参数 (M_S,K_a,α).
主要方法:
- 应用一个包含热波动和随机放松过程的随机朗格温模型.
- 通过贝叶斯优化 (BO) 和高斯过程 (GP) 回归,将模型配合实验交流歇斯底里循环.
- 估计参数与实验测量和磁化 (M_S) 相比进行验证.
主要成果:
- 在商业MNP的模拟和实验交流磁化歇斯底里循环之间实现了高保真性合适.
- 对和磁化 (M_S),有效异构性 (K_a) 和吉尔伯特阻尼参数 (α) 的可靠估计.
- 在四个商业MNP产品上成功验证了模型和参数估计方法.
结论:
- 随机朗格温模型为分析MNP动态磁化提供了一个物理基础的框架.
- 结合的BO/GP方法可以从AC歇斯底里测量中准确确定内在磁性质.
- 这种方法推进了用于各种应用的磁纳米粒子的表征.
相关概念视频
Paramagnetism
3.1K
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
3.1K
Mechanistic Models: Compartment Models in Algorithms for Numerical Problem Solving
376
Mechanistic models play a crucial role in algorithms for numerical problem-solving, particularly in nonlinear mixed effects modeling (NMEM). These models aim to minimize specific objective functions by evaluating various parameter estimates, leading to the development of systematic algorithms. In some cases, linearization techniques approximate the model using linear equations.
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...
376
The Uncertainty Principle
33.9K
Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that there is a fundamental limit to how accurately one can measure both a particle’s position and its momentum simultaneously. The more accurate the measurement of the momentum of a particle is known, the less accurate the position at that time is known and vice versa. This is what is now called the Heisenberg uncertainty principle. He...
33.9K
Atomic Nuclei: Nuclear Relaxation Processes
1.3K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
1.3K
Magnetic Moment of an Electron
3.1K
Electrons revolving around a nucleus are analogous to a circular current carrying loop. This current produces a magnetic dipole moment proportional to the electron's orbital angular momentum. Since the orbital angular momentum is quantized in terms of the reduced Planck's constant, the dipole moment is quantized in the Bohr Magneton. The value of the Bohr magneton is 9.27 x 10-24 Am2. Electrons also have an intrinsic spin angular momentum, and the associated spin magnetic moment is...
3.1K
Atomic Nuclei: Nuclear Magnetic Moment
3.5K
All atomic nuclei are positively charged. When they have a nonzero spin, they behave like rotating charges. As a consequence of their charge and spin, these nuclei generate a magnetic field (B). This, in turn, gives rise to a magnetic moment (μ), which is randomly oriented in the absence of an external magnetic field. When an external magnetic field (B0) is applied, the magnetic moment vectors can align with the field or against it in 2 + 1 orientations. A hydrogen nucleus, which is just a...
3.5K


