crenic

The fluid from which they have been precipitated contains two substances, crenic and apocrenic acids, while the soil still retains what has been called insoluble humus.

Elements of Agricultural Chemistry Thomas Anderson

The acids above named do not differ greatly in chemical characters, but they have been subdivided into the humic, geic, and crenic groups, which present some differences in properties and composition.

Elements of Agricultural Chemistry Thomas Anderson

The first microscopic symptom of decay in paper is irregularity of surface, with a slight change of color, indicating the commencement of the process just noticed, during which, in addition to carbonic acid, certain organic acids are formed, as crenic and ulmic acids, which, if the paper has been stained by a coloring matter, will form spots of red on the surface.

Forty Centuries of Ink 1904

Thus the inert matters that resist the immediate solvent power of alkalies, absorb oxygen from the air, and form the humic or ulmic acids soluble in alkalies; the humic acids undergo conversion into crenic acid, and this body, by oxidation, passes into apocrenic acid.

Peat and its Uses as Fertilizer and Fuel 1869

This is sustained by the fact that the crenic, apocrenic and humic acids, though often partly uncombined, are never wholly so, but usually occur united in part to various bases, viz.: lime, magnesia, ammonia, potash, alumina and oxide of iron.

Peat and its Uses as Fertilizer and Fuel 1869

It is, however, probable that organic acids (crenic and apocrenic,) and nitric acid were also produced (by oxidation,) and shared with carbonic the work of solution.

Peat and its Uses as Fertilizer and Fuel 1869

The crenic and apocrenic acids (that are formed by the oxidation of ulmic and humic acids,) have such decided acid characters, -- crenic acid especially, which has a strongly sour taste -- that we cannot well doubt their dissolving action.

Peat and its Uses as Fertilizer and Fuel 1869

In fact, the oxidation and consequent removal of these soluble matters (crenic and apocrenic acids,) is likely to proceed more rapidly than they can be produced from the less soluble humic acid of the peat.

Peat and its Uses as Fertilizer and Fuel 1869

To this day there is a division of opinion among scientific men on this subject, some adopting the views of Liebig, others maintaining that certain soluble organic matters, viz., crenic and apocrenic acids are proper food of plants.

Peat and its Uses as Fertilizer and Fuel 1869

Furthermore, as Dr. Vœlcker has shown us, during the fermentation of the manure in a heap, ulmic and humic, crenic and apocrenic acids are produced, and these unite with the ammonia and “fix” it -- in other words, they change it from a volatile gas into a non-volatile salt.

Talks on Manures A Series of Familiar and Practical Talks Between the Author and the Deacon, the Doctor, and other Neighbors, on the Whole Subject Joseph Harris 1860