One disc was designed to give the water a positive charge
; one a negative charge; and two gave no charge at all to the water.
In this instance some of the positive charge
developed on surfaces is balanced not by adsorption of negatively charged diffuse layer ions, but by repulsion of positively charged ions from the diffuse layer (van Olphen 1963).
As the soil solution pH is decreased the net charge density becomes more positive as the positive charge
density increases and the negative charge density is reduced.
Development of positive charge
and effects on nitrate leaching
Gray dots show where positive charge
resides, and gold represents unidentified sources of radiation.
Thus an alpha particle (a helium nucleus) had four times the mass of a proton but a positive charge
only twice that of a proton.
Therefore, they cannot remove dangerous cations or dyes with positive charge
from water or textile wastewater.
So Dirac revised his idea, correctly concluding in 1931 that the holes were a new type of particle with the same mass as an electron but a positive charge
. Dirac had predicted antimatter.
That positive charge
helps to overcome another obstacle to nanoparticle drug delivery: Once the particles reach a tumor, it's difficult to get them to enter the cells.
Like poles on a magnet, the negative charge at the bottom of the thundercloud and the positive charge
of the ground are attracted to each other.
If such a particle approached a nucleus, the positive charge
of the nucleus would repel the positively charged proton, breaking it from the neutron and deflecting it away.
The research team suspects that the polymer's positive charge
and stiffness induce the clotting.