A second, acidic fraction contained a nitrophenolic compound and a mixture of carboxylic acids. And a neutral fraction included aldehydes, a lactone, a ketone, and a mix of branched and straight-chain saturated hydrocarbons. Additional analysis by Bear and Z.
Kranz a year later identified palmitic, stearic, and oleic acids as key petrichor components Aust. Working separately, Rutgers University microbiologists Nancy N. Gerber and Hubert A. Lechevalier also found a bicyclic alcohol, called geosmin, that produces the characteristic odor of fresh, moist earth Appl.
Although readers might think that rain generally promotes plant germination and growth, Bear and Thomas found that each of the different fractions of their yellow oil actually inhibits growth of cress, mustard, and grasses Nature, DOI: They suggested that the effect would be most pronounced in areas subjected to prolonged dry periods. The effect may point to a mechanism by which seed germination is inhibited unless there is sufficient rainfall to wash away the inhibitory substances and to ensure plant growth. When spring rains do cause plants to grow and flower, bees begin foraging for nectar to make honey.
The substances are important to processes in which polymers or molten glass is drawn into strands to make textile or optical fibers.
- Pietro Bembo: Prose della volgar lingua II (German Edition).
- Conscious Dance: 101 modalities that define the movement.
- The Chemical Compounds Behind The Smell Of Rain | Compound Interest?
Traditional theory says that the behavior of falling fluid is driven by gravity, not viscosity, so all fluids should behave the same. Yet a thin stream of water from a faucet breaks up into droplets after falling only about 10 cm, whereas viscous fluids such as honey can maintain strands for 10 meters or more. The wetness and force of rainfall kick these tiny spores up into the air where the moisture after a rain acts as an aerosol just like an aerosol air freshener.
Subscribe to RSS
The moist air easily carries the spores to us so we breathe them in. These spores have a distinctive, earthy smell we often associate with rainfall. The bacteria is extremely common and can be found in areas all over the world, which accounts for the universality of this sweet "after-the-rain" smell. Since the bacteria thrives in moist soil but releases the spores once the soil dries out, the smell is most acute after a rain that follows a dry spell, although you'll notice it to some degree after most rainstorms.
Another sort of smell is caused by the acidity of rain. Because of chemicals in the atmosphere, rainwater tends to be somewhat acidic, especially in urban environments. When it comes in contact with organic debris or chemicals on the ground, it can cause some particularly aromatic reactions.
It breaks apart soil and releases minerals trapped inside, and it reacts with chemicals, such as gasoline, giving them a stronger smell. These reactions generally produce more unpleasant smells than bacteria spores, which is why the after-the-rain smell isn't always a good one. Like the smell caused by the bacteria spores, the smell of chemical reactions is most noticeable when it rains following a dry spell.
This is because once the chemicals on the ground have been diluted by one downpour, they don't have the same reaction with the rainwater. Another after-the-rain smell comes from volatile oils that plants and trees release. The oil then collects on surfaces such as rocks.
What is the word for "the smell of rain"? - English Language & Usage Stack Exchange
The rain reacts with the oil on the rocks and carries it as a gas through the air. This scent is like the bacteria spores in that most people consider it a pleasant, fresh smell. It has even been bottled and sold for its aromatic qualities! These are a few common rain smells, but there are also all sorts of other scents after it rains.
There is lots of aromatic material that the moisture and impact of rain can stir up, and the moist atmosphere following a downpour is particularly good at carrying these particles through the air.
Related Scent of Rain
Copyright 2019 - All Right Reserved