The phrase 'excess number of' is correct and usable in written English.
You can use it when referring to an amount of something that is larger than something else or larger than necessary. For example, "He had an excess number of tennis rackets in his collection."
One of them is the excess number of houses.
"People with Lesch-Nyhan have an excess number of involuntary movements," Jinnah said.
The planners regarded competition as wasteful because it allowed an excess number of competitors, and then forced some to close down.
The excess number of dipoles pointing with the field is determined by (mB/kT), where mB represents the magnetic energy and kT the thermal energy.
When the magnetic energy is small compared to the thermal energy, the excess number of dipoles pointing with the field is proportional to the field and inversely proportional to the absolute temperature, corresponding to Curie's law.
The interaction between the nanoparticles is hindered by the excess number of PSS molecules.
We investigate how to exploit the excess number of thrusters to accommodate thruster faults during operation.
Additional data collection and analyses confirmed the excess number of deaths in patients treated with DCLHb but failed to reveal the cause of these deaths.
The high lattice strain in Ti200 is due to the presence of an excess number of atoms and defects on the amorphous grain boundary.
The free energy change in the surface region is calculated and is used to obtain the excess number of molecular layers in the surface region.
Knockdown of OsYABBY5 resulted in the defect of spikelet, overexpression of OsYABBY5 induced an excess number of floral organs such as pistils, stamens, and lodicules (Tanaka et al. 2012).
