Sentence examples for are difficult to observe from inspiring English sources

We observed light scattering from individual nano-sized tracers induced by high-intensity laser light, which are difficult to observe by direct observation of tracers using optical microscope in common flow velocimetry systems.

These prohibitions are difficult to observe.

These low-frequency waves are difficult to observe near Earth because of interference from human sources.

Like many other geologic features concealed beneath the earth, caves are difficult to observe.

Experimental approaches are required but rarely possible as rhinoceros are difficult to observe and manipulate.

Contemporary economic theories of bargaining depend on aspects of the bargainers' preferences that are difficult to observe.

Complexions are difficult to observe in materials made from a single element13, but recent research has shown that distinct interfacial structures become more accessible in alloys14,15.

"Through the Looking Glass: Matching Observational Diagnostics with Simulations of Star Formation" Forming stars are difficult to observe directly because they are deeply embedded in dust and gas.

The earliest stages of convergent evolution are difficult to observe in the wild, limiting our understanding of the incipient genomic architecture underlying convergent phenotypes [1, 2].

At the same time, white dwarf stars, which are difficult to observe and of which very few are known, are among the more significant contributors.

These nocturnal animals are difficult to observe in the wild, even more so now that they are growing scarce, and their habits have been "literally a black box," Ms. Olsson said.