Feeding by direct absorption of sunlight and carbon dioxide, without roots or leaves, they measure up to 50 micrometers, about 2-thousandths of an inch, in diameter.

IR spectroscopy involves measuring the direct absorption of photons with the appropriate energy to excite molecular bond vibrations.

But there is another way in which molecular vibrations can be excited by radiation, a way which does not involve direct or resonant absorption.

It leads to the Raman effect, which, as we have already seen in Chapter 5, is many orders of magnitude less efficient than direct resonant absorption.

Exposure to these solvents can occur by inhalation, ingestion, or direct absorption through the skin.

They obtain nutrition from direct absorption of dissolved substances, and to a lesser extent from particulate materials[5].

The Soviet newcomers fall into a category of "direct absorption."

Anything her body needed, it would acquire through the more efficient means of direct absorption.

Such a molecule can be excited to a higher vibrational mode through the direct absorption of a photon of the appropriate energy.

Fungi directly absorb some nutrients, such as sugar, and secrete enzymes to break down nutrients too complex for direct absorption.