Why is silica in high purity water unstable?
Of course, structure and size of the R group of substances in solubility in water also. Such as alcohol: R - OH, with the increase of R group, part of the increase of non polar molecules, so with water (polar molecules) structure difference increases, so also decreased the solubility in water.
Who can provide hydrogen for a hydrogen bond or accept solute molecules of hydrogen, and water are "similar structure." such as ROH (alcohol), RCOOH (carboxylic acid), R2C=O (ketone), RCONH2 (amide), can be combined with water through hydrogen bonding, have considerable solubility in water.
Water molecules have strong hydrogen bonds. Water molecules can not only provide hydrogen atoms for the formation of hydrogen bonds, but also have hydrogen atoms which can be accepted by other molecules because of the lone pairs of electrons in the oxygen atoms. Hydrogen bonds are the main binding force between water molecules
In the IR recovery process, the organization's MZ is over 0, but time is different. Use this characteristic to suppress an organization. As fat, because its T1 time is shorter than other tissues, take TI=0.69T1 (T1 for fat relaxation time), fat signal is better than 0 points, can not receive its signal. Highlight other organizations.When the T1 FLAIR sequence is very long, almost all of the MZ has been restored, only T1 very long tissue MZ close to 0, such as water, liquid signal is suppressed, and other special organization. FLAIR (Fluid, Attenuation, IR) is often used to suppress CSF. Application of IR sequences
