isochore

From iso- +‎ Ancient Greek χώρα (khṓra, “place”).

isochore (plural isochores)

1. In general, a place or position with relevant parameters matching other places, as in having the same pressure, chemistry, population etc. Even within a single discipline the parameter might vary according to convenience e.g. in physics alone it might refer to velocity, volume, gravity, and many more. cf. contour, isopleth.
   • 1887 Anonymous: Engineering, Volume 43 April 29th page 406

     The numerical results are given from which the authors deduce the relation for constant volume and additional reasons are given for believing acetic acid (whose vapour density at ordinary temperatures is abnormal) to be a mixture of C₂H₄O₂ and C₄H₈0₄, the former preponderating as the temperature rises. The authors ask the Society for a name to designate lines connecting pressure and temperature at constant volume, and for which they suggested “isochore”...

2. (physics) A line drawn on a graph showing the variation of the pressure of a constant volume of gas as it varies with temperature.
   • 1916, William Cudmore McCullagh Lewis, A System of physical chemistry, volume 1, page 92:

     An isochore is a curve on a PVT diagram, the pressure and temperature being variable, the volume invariable.

   • 1956, Enrico Fermi, Thermodynamics, page 7:

     Thus, an isochore transformation in this case is a transformation at constant volume.

   • 1992, J M Yeomans, Statistical Mechanics of Phase Transitions, page 2:

     1.3 shows the specific heat of argon measured along the critical isochore.

3. (geology) A contour showing points of equal vertical thickness of strata; equal to an isopach if strata are horizontal.
   • 1964, Mineral Development in Assam: Symposium Volume, Assam (India) Directorate of Geology and Mining, page 205:

     The isochore plan of the overburden thus obtained is then placed over the isochore plan of the seam.

   • 1981, Coalfields of India, Geological Survey of India, page 125:

     Isochore maps of the sandstone bodies also indicate the presence of a number of channels flowing from the basin margin towards a central depression.

4. (genetics) A sequence of DNA that has a reasonably constant proportion of pairs of guanine and cytosine bases, and is rich in genes.
   • 1998, Lindsey R Lindsey, Alan R Lindsey, Transgenic Plant Research, page 268:

     A model that accounts for the differential recognition of transgenes integrated at different chromosomal locations, is the isochore hypothesis.

   • 1999, Solomon Pavlovich Vasser, Eviatar Nevo, “Scheme of the isochore organization of the human genome”, in Evolutionary Theory and Processes: Papers in Honour of Eviatar Nevo, page 117:

• choosier

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isochore f (plural isochores)

1. isochore