弱磁场对同位素溶液中中性自由基之间的反应的影响
Claire B Vink1, Jonathan R Woodward
1Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K.
Journal of the American Chemical Society
|December 23, 2004
概括
磁场影响了由2-基-4'-(2-基中毒)-2-甲基烯形成的基的重组. 低磁场 (<5 mT) 加快了基因重组,而高磁场 (>5 mT) 则减缓了.
科学领域:
- 摄影化学的使用.
- 化学动力学 化学动力学
- 频谱学是一种光谱学.
背景情况:
- 激素重组是光化学中的一个基本过程.
- 了解影响激素对动态的因素对于控制化学反应至关重要.
研究的目的:
- 为了研究磁场对基因重组率的影响.
- 阐明磁场强度在激素对重组动力学中的作用.
主要方法:
- 时间分辨率红外光谱学被用来监测激素重组.
- 这项研究是在同位素溶液中进行的,使用2 - 基 - 4 - - - - - - - - - 2 - 基基) - 2 - - 甲基烯作为模型化合物.
主要成果:
- 观察到,激进重组率取决于磁场强度.
- 在磁场>5mT时,发现重组率下降.
- 在磁场<5mT时观察到重组率的增加.
结论:
- 磁场对激素重组动态产生重大影响.
- 观察到的效应表明,激素对旋转状态和外部磁场之间存在复杂的相互作用.
相关概念视频
Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
Electrolytes: van't Hoff Factor
Colligative Properties of ElectrolytesThe colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one dissolved...
Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
π Electron Effects on Chemical Shift: Overview
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0, resulting in...
Ionic Strength: Effects on Chemical Equilibria
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary cation—the calcium...
In this solution, the primary cation—the calcium...
Theory of Strong Electrolytes
The interionic forces of the strong electrolytes depend on the solvent's dielectric constant, which is the ability of a solvent to store electrical energy, based on its polarizability. and the solution's concentration. In high-dielectric solvents and in dilute solutions, weak electrostatic forces keep ions apart. However, in low-dielectric solvents or concentrated solutions, stronger interionic forces may cause ions to pair up as ionic doublets despite being fully ionized. The theory of strong...


