Sentence examples for so difficult to detect from inspiring English sources

Why have the missing baryons been so difficult to detect?

The damage has gone unrepaired for some time, partly because it was so difficult to detect.

It is not so difficult to detect adsorbed atoms and molecules on solid surfaces, but their reaction processes are still difficult to direct.

This may serve to explain why it has been so difficult to detect substantial changes in vital rates obtained in process-oriented research.

It is the strength of this overall motivation that makes further incidents like Charlie Hebdo so difficult to detect and to stop in France, Britain and elsewhere.

He added that cooperation in insider trading cases should be rewarded because the crime, in many instances, can be so difficult to detect.

With many web portals, so-called "malicious access morphing" is as difficult to detect as screen-scraping.

It would appear, therefore, that this amygdala projection is very light and diffuse, and so extremely difficult to detect with autoradiography.

Neuroblastoma cultures over MEA have a very low signal/noise ratio response to stimulation, so it is difficult to detect small changes in spike activity in the culture during experiments.

It probes the Web very broadly without interacting directly with any target site, so it's difficult to detect.

The ultrafast photochemical processes, essential for capturing the excitation energy to drive the subsequent hydride- and proton-transfer chemistry, have so far proven difficult to detect.