Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

Travelling Waves01:04

Travelling Waves

5.2K
A wave is a disturbance that propagates from its source, repeating itself periodically, and is typically associated with simple harmonic motion. Mechanical waves are governed by Newton's laws and require a medium to travel. A medium is a substance in which a mechanical wave propagates, and the medium produces an elastic restoring force when it is deformed.
Water waves, sound waves, and seismic waves are some examples of mechanical waves. For water waves, the wave propagation medium is...
5.2K
Back EMF01:24

Back EMF

2.9K
Generators convert mechanical energy into electrical energy, whereas motors convert electrical energy into mechanical energy. A motor works by sending a current through a loop of wire located in a magnetic field. As a result, the magnetic field exerts a torque on the loop. This rotates a shaft, extracting mechanical work from the electrical current sent in initially. When the coil of a motor is turned, magnetic flux changes through the coil, and an emf (consistent with Faraday's law) is...
2.9K
Propagation of Waves01:07

Propagation of Waves

2.3K
When a wave propagates from one medium to another, part of it may get reflected in the first medium, and part of it may get transmitted to the second medium. In such a case, the interface of the two mediums can be considered as a boundary that is neither fixed nor free.
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
2.3K
Reflection of Waves01:07

Reflection of Waves

3.7K
When a wave travels from one medium to another, it gets reflected at the boundary of the second medium. A common example of this is when a person yells at a distance from a cliff and hears the echo of their voice. The sound waves (longitudinal waves) traveling in the air are reflected from the bounding cliff. Similarly, flipping one end of a string whose other end is tied to a wall causes a pulse (transverse wave) to travel through the string, which gets reflected upon reaching the wall. In...
3.7K
Interference and Superposition of Waves01:07

Interference and Superposition of Waves

5.2K
When two waves of the same nature occur in the same region simultaneously, they result in interference. Interference of waves implies that the net effect of the waves is the sum of the individual waves' effects. However, it does not imply that the individual waves affect the propagation of other waves.
Interference occurs in mechanical waves, such as sound waves, waves on a string, and surface water waves. Mechanical waves correspond to the physical displacement of particles. Hence,...
5.2K
Atomic Nuclei: Larmor Precession Frequency01:11

Atomic Nuclei: Larmor Precession Frequency

1.3K
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession,...
1.3K

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

Predicting sentinel lymph node metastasis in breast cancer using an interpretable machine learning approach based on multi-domain clinical features.

Breast cancer research : BCR·2026
Same author

Bisphenol A promotes esophageal carcinogenesis by activating the MMP1-PCOLCE regulatory axis and remodeling the tumor immune microenvironment.

Naunyn-Schmiedeberg's archives of pharmacology·2026
Same author

Molecular mechanism by which perfluorooctane sulfonate regulates the initiation and progression of prostate cancer via the ENTPD5-adenine axis.

Naunyn-Schmiedeberg's archives of pharmacology·2026
Same author

Intelligent logic-gate-integrated capillary fluorescence imprinted microarray sensor for rapid simultaneous detection of multiple endocrine disrupting compounds.

Talanta·2026
Same author

Clinical efficacy and platform-specific analysis of robotic navigation systems in adolescent idiopathic scoliosis: a meta-analysis.

Journal of robotic surgery·2026
Same author

Comparative clinical performance of robotic-assisted systems in spinal deformity surgery: focus on perioperative outcomes and pedicle screw accuracy.

Journal of robotic surgery·2026

相关实验视频

Updated: Jun 24, 2025

Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
07:58

Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt

Published on: August 7, 2017

9.3K

通过地震波形变化反转的内核反向

Wei Wang1,2,3, John E Vidale4, Guanning Pang5

  • 1Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.

Nature
|June 12, 2024
PubMed
概括

地球的固体内核在2003年和2008年之间旋转的速度比表面快,然后逆转方向,从2008年到2023年旋转的速度更慢. 这项基于地震波分析的发现表明,对于地球的核心动态需要新的模型.

更多相关视频

Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
06:55

Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling

Published on: August 5, 2016

8.2K
Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar
07:14

Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar

Published on: May 1, 2018

7.8K

相关实验视频

Last Updated: Jun 24, 2025

Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
07:58

Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt

Published on: August 7, 2017

9.3K
Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
06:55

Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling

Published on: August 5, 2016

8.2K
Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar
07:14

Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar

Published on: May 1, 2018

7.8K

科学领域:

  • 地质学
  • 地震学
  • 地球科学

背景情况:

  • 地球固体内核相对于表面的旋转已经从地震数据中推断出来.
  • 内核的结构和动态影响着地球的磁场.
  • 之前的研究表明内核的旋转速度有所不同.

研究的目的:

  • 准确地追踪地球内核的发展和衰退.
  • 使用地震波数据分析内核的旋转动态.
  • 调查内核运动与地球磁场之间的关系.

主要方法:

  • 在南三明治群岛收集了1991年至2023年的143对重复地震.
  • 分析了在中孔阵列上记录的穿透内核PKIKP波.
  • 在重复的地震多重中确定波形变化和逆转,以追踪内核位置.

主要成果:

  • 记录了波形变化和随后的反转,表明内核重新占据了过去的位置.
  • 证明内部核心在2003年至2008年间发生超级旋转.
  • 显示内核从2008年到2023年以两到三倍较慢的速度旋转,

结论:

  • 地球的内核表现出超旋转和随后较慢的次旋转,通过相同的路径回流.
  • 现在可以精确追踪内核的进展和回归.
  • 不同的前进和后退速度需要新的模型来描述内核,外核和地幔之间的动态.