Agriculture Reference
In-Depth Information
Figure 2.3 Two types of control
volumes when considering
environmental mass: (a) control
volume of an environmental
matrix (e.g., soil, sediment, other
unconsolidated material) or fluid
(e.g., water, air, blood); (b) a
pond. Both volumes have equal
masses entering and exiting, with
transformations and physical
changes taking place within the
control volume.
From D. A. Vallero, Environmental
Contaminants: Assessment and
Control , Elsevier Academic Press,
Burlington, MA, 2004.
Mass input
Mass output
Chemical and
reactions and
physical change
Fluid transport
into control
Fluid transport
out of control
Input to atmosphere
from aerosols
Atmospheric deposition
Discharge from outfall
Stream input
Gas exchange
Output to stream
Output to groundwater
Output to sediments
Groundwater input
Control volume boundary
Control volume boundary
Sediment input
from others. A property must be able to be stated at a specific time independent
of its value at any other time and unconstrained by the process that induced the
condition (state). An intensive property is independent of the system's mass (such
as pressure and temperature). An extensive property is a proportionality to the mass
of the system (such as density or volume). Dividing the value of an extensive
property by the system's mass gives a specific property ,suchas specific heat, specific
volume, or specific gravity.
Search WWH ::

Custom Search