longitudinal magnetisation

简明释义

纵向磁化

英英释义

例句

1.Researchers are studying how different materials influence the longitudinal magnetisation in MRI scans.

研究人员正在研究不同材料如何影响MRI扫描中的纵向磁化。

2.To optimize imaging techniques, understanding longitudinal magnetisation is crucial.

为了优化成像技术，理解纵向磁化是至关重要的。

3.The MRI machine relies heavily on the principles of longitudinal magnetisation to create detailed images of internal organs.

MRI机器在创建内部器官的详细图像时，严重依赖于纵向磁化的原理。

4.The process of flipping spins in a magnetic field affects the rate of longitudinal magnetisation decay.

在磁场中翻转自旋的过程会影响纵向磁化衰减的速率。

5.In NMR experiments, the recovery of longitudinal magnetisation is essential for accurate signal detection.

在核磁共振实验中，纵向磁化的恢复对于准确的信号检测至关重要。

作文

In the field of magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR), understanding the concept of longitudinal magnetisation is crucial. Longitudinal magnetisation refers to the component of the magnetisation vector that aligns parallel to the external magnetic field. This phenomenon occurs when nuclear spins in a sample are subjected to a strong magnetic field, causing them to align with the field direction. The significance of longitudinal magnetisation lies in its role during the relaxation processes following radiofrequency (RF) excitation. To delve deeper into this topic, it is essential to distinguish between two types of relaxation: T1 and T2. T1 relaxation, also known as spin-lattice relaxation, describes the process through which longitudinal magnetisation recovers after being disturbed by an RF pulse. When the RF pulse is applied, the spins are flipped from their equilibrium state, disrupting the alignment of longitudinal magnetisation. Over time, these spins return to their original state, leading to the recovery of longitudinal magnetisation. This recovery is influenced by the surrounding molecular environment and can vary significantly among different tissues or substances.The importance of longitudinal magnetisation extends beyond theoretical understanding; it has practical implications in medical imaging. For instance, in MRI scans, the time it takes for longitudinal magnetisation to recover (T1 time) can provide valuable information about the tissue characteristics. Different tissues have different T1 values, which can be utilized to differentiate between healthy and pathological states. For example, fat tissue has a shorter T1 relaxation time compared to water-rich tissues, allowing radiologists to identify anomalies in scans effectively.Moreover, the manipulation of longitudinal magnetisation is a fundamental aspect of various imaging techniques. By adjusting the timing and parameters of the RF pulses, practitioners can enhance the visibility of certain tissues or conditions. Techniques such as inversion recovery sequences exploit the principles of longitudinal magnetisation to suppress signals from fat, thereby improving the contrast of the images obtained.Furthermore, understanding longitudinal magnetisation is also vital in research settings. Scientists often study the dynamics of longitudinal magnetisation to gain insights into molecular interactions and structural properties of materials. This knowledge can lead to advancements in fields such as chemistry and materials science, where NMR spectroscopy is employed to analyze complex mixtures and compounds.In conclusion, the concept of longitudinal magnetisation is integral to the functioning of MRI and NMR technologies. Its understanding not only facilitates better imaging techniques but also enhances our comprehension of molecular behavior in various scientific disciplines. As technology continues to evolve, the study of longitudinal magnetisation will undoubtedly play a pivotal role in advancing both medical diagnostics and scientific research.

在磁共振成像（MRI）和核磁共振（NMR）领域，理解纵向磁化的概念至关重要。纵向磁化指的是与外部磁场平行对齐的磁化矢量分量。当样品中的核自旋受到强磁场的影响时，会导致它们与磁场方向对齐。这一现象的意义在于它在射频（RF）激发后的弛豫过程中所起的作用。深入探讨这个主题，有必要区分两种弛豫：T1和T2弛豫。T1弛豫，也称为自旋-晶格弛豫，描述了纵向磁化在RF脉冲干扰后恢复的过程。当施加RF脉冲时，自旋从其平衡状态翻转，破坏了纵向磁化的对齐。随着时间的推移，这些自旋会返回到原始状态，从而导致纵向磁化的恢复。这种恢复受到周围分子环境的影响，并且在不同的组织或物质之间可能会有显著差异。纵向磁化的重要性超越了理论理解，它在医学成像中具有实际意义。例如，在MRI扫描中，纵向磁化的恢复时间（T1时间）可以提供有关组织特征的宝贵信息。不同的组织具有不同的T1值，可以用于区分健康和病理状态。例如，脂肪组织的T1弛豫时间比富含水的组织短，从而使放射科医生能够有效识别扫描中的异常。此外，操控纵向磁化是各种成像技术的基本方面。通过调整RF脉冲的时间和参数，医生可以增强某些组织或病症的可见性。反转恢复序列等技术利用纵向磁化的原理来抑制脂肪信号，从而改善所获得图像的对比度。此外，理解纵向磁化在研究环境中也至关重要。科学家们经常研究纵向磁化的动态，以深入了解分子相互作用和材料的结构特性。这一知识可以推动化学和材料科学等领域的进步，其中NMR光谱用于分析复杂混合物和化合物。总之，纵向磁化的概念对于MRI和NMR技术的运行至关重要。它的理解不仅促进了更好的成像技术，还增强了我们对各科学学科中分子行为的理解。随着技术的不断发展，纵向磁化的研究无疑将在推动医学诊断和科学研究方面发挥关键作用。