相关实验视频
Updated: Jul 14, 2026

10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
光驱动的分子电机:在单向旋转时,逐步的热螺旋反转,使体过度拥挤的双三体变频
Matthijs K J ter Wiel1, Richard A van Delden, Auke Meetsma
1Department of Organic and Molecular Inorganic Chemistry, Stratingh Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|October 13, 2005
概括
研究人员探索了状过度拥挤的双三体,发现替代物大小影响单向旋转. 这些分子电机通过光化学和热步骤展现360度的旋转,微妙的热效应影响速度.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 固态过度拥挤的基是开发分子机器的关键组成部分.
- 状双三体具有独特的旋转特性,在纳米技术中具有潜在的应用.
研究的目的:
- 为了研究替代物大小如何影响奇拉过度拥挤的双phenanthrylidenes的单向旋转.
- 阐明这些分子电机中热和光化学异构的机制.
主要方法:
- 合成和表征三种用不同替代剂 (甲基,乙基,i-propyl) 结合过多的基.
- 使用光谱技术分析热和光化学异构化过程.
- 使用核磁共振 (NMR) 和X射线晶体学进行结构阐明.
主要成果:
- 使用甲基和乙基替代剂的双三烯体通过四步序列 (两个光化学 cis-trans 异体化,两个热螺旋逆转) 展示了类似的单向 360 度旋转.
- 观察到轻微的热效应,导致乙烯替代电机的旋转稍快一些.
- 由i-propyl替代的化合物也执行单向旋转,尽管它的机制涉及不同的中间体,正如光谱数据所证明的那样.
- 鉴定出类似体的形式是中间体,证实了热螺旋逆转的逐步性质.
结论:
- 替代物大小在合过度拥挤的双三体的旋转动态中起作用.
- 这些化合物作为有效的分子电机,能够单向360度旋转.
- 该研究提供了对热螺旋逆转过程的机械洞察力,突出了其逐步的性质.
相关概念视频
Force On A Current Loop In A Magnetic Field
Magnetic forces on wires carrying current are most frequently applied in motors. A DC motor is a device that converts electrical energy into mechanical work. In motors, wire loops are enclosed in a magnetic field. When current flows through the loops, the magnetic field applies torque, which causes the shaft to rotate. The direction of the current is reversed once the loop's surface area is lined up with the magnetic field, causing a constant torque on the loop. During the process, commutators...
Faraday Disk Dynamo
A Faraday disk dynamo is a DC generator, producing an emf that is constant in time. It consists of a conducting disk that rotates with a constant angular velocity in the magnetic field, perpendicular to the disk's plane. The rotation of the disk causes a change in magnetic flux, which induces an emf, causing opposite charges to develop on the rim and in the center of the disk. The polarity of the induced emf can be determined by the direction of the magnetic field and the direction of the...
Back EMF
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 induced.
Generation of Three-Phase Voltage
A three-phase AC generator has a rotor with a rotating magnet placed within the stator mounted with the stationary three-phase winding to generate three-phase voltages via mutual induction. These windings are evenly distributed around the inner circumference of the stator and are arranged 120 electrical degrees apart. Three-phase stator windings consist of three separate coils or groups of coils, known as phases, each connected in Y (star) configuration or Delta configuration.
As the rotor...
As the rotor...
Electro-mechanical Systems
Electromechanical systems are intricate configurations that effectively combine electrical and mechanical elements to achieve a desired outcome. Central to many of these systems is the DC motor, a device that converts electrical energy into mechanical motion, enabling various applications ranging from simple fans to complex robotic mechanisms.
A key component of the DC motor is the armature, a rotating circuit positioned within a magnetic field. As an electric current passes through the...
A key component of the DC motor is the armature, a rotating circuit positioned within a magnetic field. As an electric current passes through the...
Sequence Networks of Rotating Machines
A Y-connected synchronous generator, grounded through a neutral impedance, is designed to produce balanced internal phase voltages with only positive-sequence components. The generator's sequence networks include a source voltage that is exclusively in the positive-sequence network. The sequence components of line-to-ground voltages at the generator terminals illustrate this configuration.
Zero-sequence current induces a voltage drop across the generator's neutral impedance and other...
Zero-sequence current induces a voltage drop across the generator's neutral impedance and other...

