The phrase "a given substance" is correct and usable in written English.
It can be used when referring to a specific substance that has been previously mentioned or is understood in the context.
Example: "In the experiment, we analyzed the effects of a given substance on plant growth."
Alternatives: "a specific substance" or "a particular substance".
Drug users typically weigh the risks and dosage of a given substance before taking it.
"Regular," in this case, means people who report using a given substance in the past month.
Indeed, modeling allows determining the total response pattern of a given substance.
Generally, the methods which enable the measurement of a given substance concentration in a material are slow and destructive.
He has seventeen trained tasters on his staff, and they work for academia and industry, answering the often difficult question of what a given substance tastes like.
Equation of state, any of a class of equations that relate the values of pressure, volume, and temperature of a given substance in thermodynamic equilibrium.
The above categories cover the behaviour of most engineering and naturally occurring materials, although it may sometimes be difficult to place a given substance in any one category.
Much of the confusion stems from the fact that researchers in many of these cases cannot conduct controlled experiments on humans to prove definitively that harm results from exposure (or lack of exposure) to a given substance.
The specific heat capacities (the number of heat units necessary to raise the unit of mass of a given substance one degree of temperature) of iron, aluminium and copper, for example, vary widely.
Likewise, the receptors, enzymes, and other cellular components made from these molecules are chiral and tend to interact selectively with only one or two enantiomers of a given substance.
The corrosive action of a given substance varies considerably with its concentration, the temperature, any impurities that it may contain, local differences of oxygen concentration, the degree of agitation, and the possible presence of abrasive particles.
