Wordplay welcomes ISOTHERMS back to the New York Times Crossword, after a hiatus of more than 60 years. 40D.
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Close up of the Planckian locus in the CIE 1960 color space, with the isotherms in mireds. Note the even spacing of the isotherms when using the reciprocal temperature scale. The even spacing of the isotherms on the locus implies that the mired scale is a better measure of perceptual color difference than the temperature scale. Close up of the Planckian locus in the CIE 1960 color space, with the isotherms in kelvins.
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Isotherms of real gas Dark blue curves – isotherms below the critical temperature. Green sections – metastable states. The section to the left of point F – normal liquid. Point F – boiling point.
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Isotherms in the second region will show the feature of mechanism transition. Isotherms in the third region will show the feature of supercritical adsorption. The transition will take a continuous way if the isotherms in both sides of the critical temperature belong to the same type, such as adsorption on microporous activated carbon. However, discontinuous transition could be observed on isotherms in the second region if there is a transformation of isotherm types, such as adsorption on mesoporous silica gel.
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A detailed analysis of the shape of these isotherms is done using the Kelvin equation. This enables the pore size distribution to be determined. While this is a relatively simple method of analyzing the isotherms, a more in depth analysis of the isotherms is done using the BET method. Another method of determining the pore size distribution is by using a procedure known as Mercury Injection Porosimetry.
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Water activity is related to water content in a non- linear relationship known as a moisture sorption isotherm curve. These isotherms are substance- and temperature-specific. Isotherms can be used to help predict product stability over time in different storage conditions.
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In one of the earlier studies conducted by Manes, M., & Hofer, L. J. E., the Polyani theory was used to characterize liquid-phase adsorption isotherms on various concentrations activated carbon using a wide range of organic solvent. The polyani theory was shown to be a good fit for these various systems. Because of the results, the study introduced the possibility of predicting isotherms for similar systems using minimal data. However, the limitation is that the adsorption isotherms for a large variety of solvents can only fit over a limited range.
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The dog whelk lives in rocky shores, and estuarine conditions. Climatically it lives between the 0 °C and 20 °C isotherms.
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DVS was originally developed to replace the time and labor-intensive desiccators and saturated salt solutions to measure water vapor sorption isotherms.
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Butt, Hans-Jürgen, Kh Graf, and Michael Kappl. "Measurement of Adsorption Isotherms". Physics and Chemistry of Interfaces. Weinheim: Wiley-VCH, 2006. 206-09.
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The exception is very near absolute zero, where the density of adiabats drops sharply and they become rare (see Nernst's theorem). The right diagram is a P–V diagram with a superposition of adiabats and isotherms: The isotherms are the red curves and the adiabats are the black curves. The adiabats are isentropic. Volume is the horizontal axis and pressure is the vertical axis.
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Retrieved on 2007-11-25. Maps containing station models aid in the drawing of isotherms, which more readily identifies temperature gradients,DataStreme. AIR TEMPERATURE PATTERNS. Retrieved on 2007-11-25.
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Because the process takes advantage of the nonlinearity of the isotherms, a larger column feed can be separated on a given column with the purified components recovered at significantly higher concentrations.
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Because the process takes advantage of the nonlinearity of the isotherms, a larger column feed can be separated on a given column with the purified components recovered at significantly higher concentration.
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The main application of DVS is to measure water sorption isotherms. In general, a vapor sorption isotherm shows the equilibrium amount of vapor sorbed as a function of steady state relative vapor pressure at a constant temperature. For water sorption isotherms, water relative vapor pressure is more commonly expressed as relative humidity. In a DVS experiment this is accomplished by exposing a sample to a series of step changes in relative humidity and monitoring the mass change as a function of time.
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Classification of Sorption Isotherms by Brunauer Type I through V. He found that Type II and Type III isotherms require highly porous materials or desiccants, with first monolayer adsorption, followed by multilayer adsorption and finally leading to capillary condensation, explaining these materials high moisture capacity at high relative humidity.Brunauer, S. “The Absorption of Gasses and Vapors, Volume 1,” Oxford University Press, 1943, p.49 Care must be used in extracting data from isotherms, as the representation for each axis may vary in its designation. Brunauer provided the vertical axis as moles of gas adsorbed divided by the moles of the dry material, and on the horizontal axis he used the ratio of partial pressure of the gas just over the sample, divided by its partial pressure at saturation.
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Streamline analysis of the tropical Pacific Ocean A surface weather analysis is a type of weather map that depicts positions for high- and low-pressure areas, as well as various types of synoptic scale systems such as frontal zones. Isotherms can be drawn on these maps, which are lines of equal temperature. Isotherms are drawn normally as solid lines at a preferred temperature interval. They show temperature gradients, which can be useful in finding fronts, which are on the warm side of large temperature gradients.
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Streamline analysis of the tropical Pacific Ocean A surface weather analysis is a type of weather map that depicts positions for high and low-pressure areas, as well as various types of synoptic scale systems such as frontal zones. Isotherms can be drawn on these maps, which are lines of equal temperature. Isotherms are drawn normally as solid lines at a preferred temperature interval. They show temperature gradients, which can be useful in finding fronts, which are on the warm side of large temperature gradients.
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More modern isotherms showing the sorption of water vapor, on the vertical axis, provide the ratio of the weight of water adsorbed divided by its dry weight , or that ratio converted into a percentage. On the horizontal axis they provide relative humidity or water activity of the air presented to the material. Sorption Isotherms are named as such because the equilibrium established must be for a constant temperature and this temperature should be specified. Normally, materials hold less moisture when they are hotter, and more moisture when they are colder.
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Akademische Verlagsgesellschaft, 1909. This equation is known as Freundlich adsorption isotherm or Freundlich adsorption equation. As this relationship is entirely empirical, in the case where adsorption behavior can be properly fit by isotherms with a theoretical basis, it is usually appropriate to use such isotherms instead (see for example the Langmuir and BET adsorption theories). The Freundlich equation is also derived (non- empirically) by attributing the change in the equilibrium constant of the binding process to the heterogeneity of the surface and the variation in the heat of adsorption..
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It is observed that both these longitudes experience deepening of the isotherms in April and October, but the effect is more pronounced at 97°E (isotherms deepen by 30m in April and 10m in October). This is a concrete signature of downwelling in the basin and is definitely not forced locally as the winds are weaker during this period. This confirms unequivocally that the sudden burst of water into the basin through the straits, the intensification of eastern boundary currents and the coincidental deepening of isotherms in April and October are the direct consequence of the propagation of downwelling Kelvin waves in the Andaman Sea, remotely forced by equatorial Wyrtki jets. The evolution of vorticity in the basin is suggestive of strong shear in the flow during different times of the year, and further indicates the presence of low frequency geophysical waves (such as westward propagating Rossby waves) and other transient eddies.
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Of those, 68, 69, and 70 show high affinities for carbon dioxide, evidenced by their adsorption isotherms, which show steep uptakes at low pressures. One liter of ZIF can hold 83 liters of . This could also be useful for pressure-swing adsorption.
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The surface pressure during the monolayer collapse may remain approximately constant (in a process near the equilibrium) or may decay abruptly (out of equilibrium - when the surface pressure was over-increased because lateral compression was too fast for monomolecular rearrangements). File:P-A-Char surfactant.jpg Figure 3. (i) Surface pressure – Area isotherms.
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Frogfishes live in the tropical and subtropical regions of the Atlantic and Pacific, as well as in the Indian Ocean and the Red Sea. Their habitat lies for the most part between the 20 °C isotherms, in areas where the surface level water usually has a temperature of or more. They extend beyond the 20 °C isotherms in the area of the Azores, Madeira and the Canary Islands, along the Atlantic coast of the United States, on the south coast of Australia and the northern tip of New Zealand, coastal Japan, around Durban, South Africa, and at Baja California, Mexico.Antennariidae: Frogfishes Tree of Life Web Project The greatest diversity of species is in the Indo- Pacific region, with the highest concentration around Indonesia.
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A Stirling cycle is like an Otto cycle, except that the adiabats are replaced by isotherms. It is also the same as an Ericsson cycle with the isobaric processes substituted for constant volume processes. # TOP and BOTTOM of the loop: a pair of quasi-parallel isothermal processes # LEFT and RIGHT sides of the loop: a pair of parallel isochoric processes Heat flows into the loop through the top isotherm and the left isochore, and some of this heat flows back out through the bottom isotherm and the right isochore, but most of the heat flow is through the pair of isotherms. This makes sense since all the work done by the cycle is done by the pair of isothermal processes, which are described by Q=W.
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Sorption isotherms for hexane and methanol show that the adsorbent has a mesoporous structure. Presence of methyl groups on the surface provides their hydrophobic properties. PMSPH particles tend to form a continuous network in the suspension to reduce interaction of the hydrophobic groups SiCH3 with water. These particles can be viewed as 2D sheets rather than 3D solids.
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A capillary does not necessarily have to be a tubular, closed shape, but can be any confined space with respect to its surroundings. Capillary condensation is an important factor in both naturally occurring and synthetic porous structures. In these structures, scientists use the concept of capillary condensation to determine pore size distribution and surface area through adsorption isotherms.
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A sorption calorimetric experiment is performed at isothermal regime, but different temperatures can be studied in separate experiments. In a sorption calorimetric experiment, a two-chamber calorimetric cell is inserted into a double-twin microcalorimeter.Wadsö, I. and L. Wadsö, A new method for determination of vapour sorption isotherms using a twin double microcalorimeter. Thermochimica Acta, 1996.
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In Turkey and North Africa it is a mountain species. The breeding areas have July isotherms between 17-18 °C and 26 °C (63-64 °F and 79 °F). 1411-1416 This treecreeper is essentially non-migratory but post-breeding dispersal may lead to vagrancy outside the normal range. It has occurred as a vagrant to England, Sweden, Lithuania and the Balearic Islands.
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L Zhou and coworkers used a volumetric apparatus to measure the adsorption equilibriums of hydrogen and methane on activated carbon (Figure 2, 3). They also measure the adsorption equilibriums of nitrogen on microporous activated carbon (Figure 4) and on a mesoporous silica gel (Figure 5) for both subcritical and supercritical region. Figure 6 shows the isotherms of methane on silica gel.
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Bottom topography, the third formation process of Haida eddies, can occur because the Alaska current will interact with hills or rock formations below the surface, and this can cause baroclinic instabilities. An idealized eddy in the Gulf of Alaska. "Isotherms" are lines connecting points of equal temperature. Warm, nutrient-rich coastal water spirals clockwise, forming the core of the eddy.
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Strain is focused into weakness forcing warm material into the zone thereby lifting isotherms locally Figure 2: An advanced tectonic aneurysm. Isothermal gradient becomes more advanced than in the young stage. Material flow causes surface uplift of young rock on the peripheral edges of the erosion area. The uplift brings weak warm rocks to the surface and creates high relief.
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Mostly, SIRs have been investigated and used for the recovery of heavy metals.Warshawsky, A.; Cortina, J. L.; Aguilar, M.; Jerabek, K. (1999). “New Developments in Solvent Impregnated Resins. An Overview.” International Solvent Extraction Conference 1999, Barcelona, SpainSerarols, J.; Poch, J.; Villaescusa, I. (2001). “Expansion of adsorption isotherms into equilibrium surface Case 1: solvent impregnated resins (SIR).” React. Funct. Polym. 48 37-51.
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In 1957, he suggested a straightforward criterion for ferromagnetism from observations of magnetic isotherms. This method was called Arrott plots. In collaboration with Murray J. Press, he gave a description of surface singularities in liquid-crystal droplets. A lot of works are devoted to the properties of ferromagnetic samples (for example the so-called Arrott's cylinder) with micrometer and sub-micrometer sizes.
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The adsorption of gases and solutes is usually described through isotherms, that is, the amount of adsorbate on the adsorbent as a function of its pressure (if gas) or concentration (for liquid phase solutes) at constant temperature. The quantity adsorbed is nearly always normalized by the mass of the adsorbent to allow comparison of different materials. To date, 15 different isotherm models have been developed.
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DVS measurement has applications over a wide range of industries. Both equilibrium vapor sorption isotherms and vapor sorption kinetic results can yield vital information for materials ranging from pharmaceuticals to fuel cells. Although water sorption experiments are most common, the use of organic vapor in DVS experiments can reveal additional sample properties. The below sections highlight how DVS experiments are utilized in several industries.
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In the United States, rainfall plotted in the corner of the station model are in inches. The international standard rainfall measurement unit is the millimeter. Once a map has a field of station models plotted, the analyzing isobars (lines of equal pressure), isallobars (lines of equal pressure change), isotherms (lines of equal temperature), and isotachs (lines of equal wind speed) are drawn.CoCoRAHS. INTRODUCTION TO DRAWING ISOPLETHS.
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By plotting the freezing line, isotherms can be useful in determination of precipitation type. Mesoscale boundaries such as tropical cyclones, outflow boundaries and squall lines also are analyzed on surface weather analyses. Isobaric analysis is performed on these maps, which involves the construction of lines of equal mean sea level pressure. The innermost closed lines indicate the positions of relative maxima and minima in the pressure field.
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They mostly migrate south in winter, typically to regions in the temperate zone between the January 0 °C (32 °F) to 5 °C (41 °F) isotherms. The genus contains 11 living species, which span nearly the whole range of true goose shapes and sizes. The largest is the greylag goose at . All have legs and feet that are pink, or orange, and bills that are pink, orange, or black.
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By plotting the freezing line, isotherms can be useful in determination of precipitation type. Mesoscale convective systems such as tropical cyclones, outflow boundaries and squall lines also are analyzed on surface weather analyses. Isobaric analysis is performed on these maps, which involves the construction of lines of equal mean sea level pressure. The innermost closed lines indicate the positions of relative maxima and minima in the pressure field.
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This uses the volume of mercury taken up by the solid as the pressure increases to create the same isotherms mentioned above. An application where pore size is beneficial is in regards to oil recovery.Tehrani, D. H.; Danesh, A.; Sohrabi, M.; Henderson, G. Enhanced Oil Recovery by Water Alternating Gas (WAG) Injection SPE, 2001. When recovering oil from tiny pores, it is useful to inject gas and water into the pore.
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Various types of graphs in thermodynamics, engineering, and other sciences use isobars (constant pressure), isotherms (constant temperature), isochors (constant specific volume), or other types of isolines, even though these graphs are usually not related to maps. Such isolines are useful for representing more than two dimensions (or quantities) on two-dimensional graphs. Common examples in thermodynamics are some types of phase diagrams. Isoclines are used to solve ordinary differential equations.
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The sample mass must be allowed to reach gravimetric equilibrium at each step change in humidity before progressing to the next humidity level. Then, the equilibrium mass values at each relative humidity step are used to generate the isotherm. Isotherms are typically divided into two components: sorption for increasing humidity steps and desorption for decreasing humidity steps. Sorption can be further divided into adsorption (sorbate located on the surface) and absorption (sorbate penetrates the bulk).
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Figure 1 shows a typical water sorption result from a DVS experiment for a microcrystalline cellulose sample. The kinetic data (Figure 1a) shows the change in mass and humidity as a function of time. From the kinetic results, the rate of water uptake and water diffusion coefficients can be determined. The equilibrium mass values at the end of each humidity step were used to calculate the sorption and desorption isotherms (Figure 1b).
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Figure 1. Several isotherms of an ideal gas on a p-V diagram For the special case of a gas to which Boyle's law applies, the product pV is a constant if the gas is kept at isothermal conditions. The value of the constant is nRT, where n is the number of moles of gas present and R is the ideal gas constant. In other words, the ideal gas law pV = nRT applies.
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The cycle began with a deformation phase unaccompanied by metamorphism. This evolved into the second phase accompanied by broad regional metamorphism as thermal doming began. With continued updoming of the isotherms, the third phase produced minor folding but caused major metamorphic recrystallization, resulting in the emplacement of granite at the core of the thermal dome. This phase occurred at lower pressure because of erosional unloading, but the temperatures were more extreme, ranging up to about .
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Bell, L.N., and Labuza, T.P. 2000. "Practical Aspects of Moisture Sorption Isotherm Measurement and Use". 2nd Edition AACC Eagan Press, Eagan, MN BET theory (Brunauer-Emmett-Teller) provides a calculation to describe the physical adsorption of gas molecules on a solid surface. Because of the complexity of the process, these calculations are only moderately successful; however, Stephen Brunauer was able to classify sorption isotherms into five generalized shapes as shown in Figure 2.
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At a certain point, the pressure will decrease substantially moving from convergent basement rock into thinned crust. This causes rapid decompression at relatively stable and raised isotherms. Decompression melting occurs, which increases the proportion of partial melt within the material and causes rapid heat advection towards the surface. Continued convergent plate movement focuses the flow of material into the syntaxial areas with the localized weakness permitting upward escape as an accommodation mechanism.
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The difference in water vapor uptake between the sorption and desorption isotherms is called the hysteresis. The shape and location of the isotherm hysteresis can elucidate information about the sorption mechanism and sample porosity. Although an isotherm experiment is the most common use of a DVS instrument, humidity (or other vapor) ramping experiments can be performed to investigate vapor-induced phase changes. These changes include: glassy to rubbery transitions, amorphous to crystalline conversions, and sample deliquescence.
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Climate change may occur over long and short timescales from a variety of factors; recent warming is discussed in global warming. Global warming results in redistributions. For example, "a 3°C change in mean annual temperature corresponds to a shift in isotherms of approximately 300–400 km in latitude (in the temperate zone) or 500 m in elevation. Therefore, species are expected to move upwards in elevation or towards the poles in latitude in response to shifting climate zones".
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Retrieved on 2006-10-22. There is normally a broad temperature gradient behind the boundary with more widely spaced isotherms. A wide variety of weather can be found along a stationary front, but usually clouds and prolonged precipitation are found there. Stationary fronts will either dissipate after several days or devolve into shear lines, but can change into a cold or warm front if conditions aloft change causing a driving of one air mass or the other.
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The Tenerife subspecies occurs in the mountain region previously occupied by laurisilva, but now dominated by tree heaths. It is common only in that habitat, becoming rare in pine forest, where it occurs only where tree-heath is also available. The goldcrest has a huge range in Eurasia, breeding from Macaronesia to Japan. It is common in middle and northern temperate and boreal latitudes of Europe, between the July isotherms, and thus predominantly in cooler climates than the firecrest.
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The tephigram was invented by Napier Shaw in 1915 and is used primarily in the United Kingdom and Canada. Other countries use similar thermodynamic diagrams for the same purpose however the details of their construction vary. In the tephigram, isotherms are straight and have a 45 degree inclination to the right while isobars are horizontal and have a slight curve. Dry adiabats are also straight and have a 45 degree inclination to the left while moist adiabats are curved.
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The nominate subspecies breeds in Europe from southern England, France, Spain and Portugal east to Belarus, northwestern Ukraine, and Greece, and north to the Baltic and southern Latvia. There are isolated populations east of the main range in Abkhazia, the Crimea and Turkey. Its range lies between the July isotherms. Southern birds are largely resident, unlike northern and eastern populations which are migratory, wintering mainly in Mediterranean areas and the far west of Europe from Portugal north to Britain.
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A surface weather analysis for the United States on October 21, 2006. A weather map, also known as synoptic weather chart, displays various meteorological features across a particular area at a particular point in time and has various symbols which all have specific meanings. Such maps have been in use since the mid-19th century and are used for research and weather forecasting purposes. Maps using isotherms show temperature gradients, which can help locate weather fronts.
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When the Carnot cycle is plotted on a pressure–volume diagram (), the isothermal stages follow the isotherm lines for the working fluid, the adiabatic stages move between isotherms, and the area bounded by the complete cycle path represents the total work that can be done during one cycle. From point 1 to 2 and point 3 to 4 the temperature is constant. Heat transfer from point 4 to 1 and point 2 to 3 are equal to zero.
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Black-and-white skew-T log-P diagram Color skew-T log-P diagram, with the temperature grid lines in red slanted to the right. Click for more details. A skew-T log-P diagram is one of four thermodynamic diagrams commonly used in weather analysis and forecasting. In 1947, N. Herlofson proposed a modification to the emagram that allows straight, horizontal isobars and provides for a large angle between isotherms and dry adiabats, similar to that in the tephigram.
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CIE 1960 UCS. The isotherms are perpendicular to the Planckian locus, and are drawn to indicate the maximum distance from the locus that the CIE considers the correlated color temperature to be meaningful: \Delta uv=\pm 0.05 The distance from the locus (i.e., degree of departure from a black body) is traditionally indicated in units of \Delta uv; positive for points above the locus. This concept of distance has evolved to become Delta E, which continues to be used today.
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HP1 binding affinity to nucleosomes containing histone H3 methylated at lysine K9 is higher than to those with unmethylated lysine K9. HP1 binds nucleosomes as a dimer and in principle can form multimeric complexes. Some studies have interpreted HP1 binding in terms of nearest-neighbor cooperative binding. However, the analysis of available data on HP1 binding to nucleosomal arrays in vitro shows that experimental HP1 binding isotherms can be explained by a simple model without cooperative interactions between neighboring HP1 dimers.
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Due to the Coriolis force acting to the left in the Southern Hemisphere and the resulting Ekman transport away from the centers of the gyre, these regions are very productive due to upwelling of cold, nutrient rich water. Strong upwelling in the gyre is shown where the deep-water isotherms curve upwards. The Weddell front, which is identical to the Southern Antarctic Circumpolar Current Front, separates the Weddell gyre from the Antarctic Circumpolar Current . The flow is cyclonic, although the cavity flow is anticyclonic.
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Moisture sorption isotherm At equilibrium, the relationship between water content and equilibrium relative humidity of a material can be displayed graphically by a curve, the so-called moisture sorption isotherm. For each humidity value, a sorption isotherm indicates the corresponding water content value at a given, constant temperature. If the composition or quality of the material changes, then its sorption behaviour also changes. Because of the complexity of sorption processes, the isotherms cannot be determined explicitly by calculation, but must be recorded experimentally for each product.
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Sample emagram An emagram is one of four thermodynamic diagrams used to display temperature lapse rate and moisture content profiles in the atmosphere. The emagram has axes of temperature (T) and pressure (p). In the emagram, the dry adiabats make an angle of about 45 degrees with the isobars, isotherms are vertical and isopleths of saturation mixing ratio are almost straight and vertical. Usually, temperature and dew point data from radiosondes are plotted on these diagrams to allow calculations of convective stability or Convective Available Potential Energy.
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S. e europaea in Sweden The Eurasian nuthatch's breeding range extends across temperate Eurasia from Great Britain (but not Ireland) to Japan. It is found between the July isotherms, north to about latitude 64°N in western Russia and 69°N in Siberia. It breeds south to the Mediterranean in Europe, although it is absent from the islands, other than Sicily, and in most of Russia the southern boundary is around 54–55°N. In the east, the range includes most of China and Taiwan and much of Korea.
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Isotherms of an ideal gas. The curved lines represent the relationship between pressure (on the vertical axis) and volume (on the horizontal axis) for an ideal gas at different temperatures: lines that are farther away from the origin (that is, lines that are nearer to the top right-hand corner of the diagram) represent higher temperatures. The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas. It is a good approximation of the behavior of many gases under many conditions, although it has several limitations.
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Illustration clouds overriding a warm front Warm fronts mark the position on the Earth's surface where a relatively warm body of air has displaced colder air. The temperature increase is located on the equatorward edge of the gradient in isotherms, and lies within broader low pressure troughs than is the case with cold fronts. Warm fronts move more slowly than do the cold fronts because cold air is denser, and harder to displace from the Earth's surface. This causes temperature differences across warm fronts to be broader in scale.
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Warm fronts are at the leading edge of a homogeneous warm air mass, which is located on the equatorward edge of the gradient in isotherms, and lie within broader troughs of low pressure than cold fronts. A warm front moves more slowly than the cold front which usually follows because cold air is denser and harder to remove from the Earth's surface. This also forces temperature differences across warm fronts to be broader in scale. Clouds ahead of the warm front are mostly stratiform, and rainfall gradually increases as the front approaches.
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Since almost all adsorptive separation processes are dynamic -meaning, that they are running under flow - testing porous materials for those applications for their separation performance has to be tested under flow as well. Since separation processes run with mixtures of different components, measuring several breakthrough curves results in thermodynamic mixture equilibria - mixture sorption isotherms, that are hardly accessible with static manometric sorption characterization. This enables the determination of sorption selectivities in gaseous and liquid phase. The determination of breakthrough curves is the foundation of many other processes, like the pressure swing adsorption.
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In waste water treatment, the most commonly used adsorbent is granular activated carbon (GAC), often used as to treat both liquid and gas phase volatile organic compounds and organic pollutants. Activated carbon beds vary in lifetime depending on the concentration of the pollutant(s) being removed, their associated adsorption isotherms, inlet flow rates and required discharge consents. Life- times of these beds can range between hours and months. Activated carbon is often landfilled at the end of its useful life but sometimes it is possible to regenerate it restoring its adsorptive capacity allowing it to be re-used.
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Since Perrin's contribution, the technique has grown from determining binding isotherms under heavily controlled parameters, to the study of antigen-antibody, small molecule-protein, and hormone-receptor binding interactions. A fluorescence polarization immunoassay was first described and used in the 1960s.The competitive homogenous characteristic allowed for the fluorescence polarization immunoassay to be automated much easier than other immunoassay techniques such as radioimmunoassays or enzyme- linked immunoassays. Despite originating as a method for direct interaction studies, the technique has been adopted by high-throughput screening (HTS) since the mid 1990s to help facilitate the drug discovery process by studying complex enzymatic interaction.
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Snowfall occurs mainly in the west and south, which can result in strong snowstorms. Patagonia's temperatures are relatively cold for its latitude due to the cold Malvinas Current (also called the Falkland(s) Current) and the high altitude. A characteristic of the temperature pattern is the NW–SE distribution of isotherms due to the presence of the Andes. The warmest parts of the region are in northern parts of Rio Negro Province and Neuquén Province, where mean annual temperatures range from , while the coldest are in western Santa Cruz Province and Tierra del Fuego Province, where mean temperatures range from .
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Coastal Arctic climates are moderated by oceanic influences, having generally warmer temperatures and heavier snowfalls than the colder and drier interior areas. The Arctic is affected by current global warming, leading to Arctic sea ice shrinkage, diminished ice in the Greenland ice sheet, and Arctic methane release as the permafrost thaws. The melting of Greenland's ice sheet is linked to polar amplification. Due to the poleward migration of the planet's isotherms (about per decade during the past 30 years as a consequence of global warming), the Arctic region (as defined by tree line and temperature) is currently shrinking.
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Higher closure temperatures were dated using argon–argon dating methods for biotite samples (300 °C) and zircon fission track dating (230 °C - 250 °C) methods. By analyzing the ages of minerals with various closure temperatures, researchers can infer the speed at which they moved through the isotherms. When the difference between the age of a mineral that cooled at a high temperature and one that cooled at a low temperature are relatively similar, then exhumation is inferred to be rapid. The geothermobarometry is obtained using garnet-biotite plagioclase in order to constrain higher pressure metamorphic regimes.
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A benchtop manifold freeze-drier The secondary drying phase aims to remove unfrozen water molecules, since the ice was removed in the primary drying phase. This part of the freeze-drying process is governed by the material's adsorption isotherms. In this phase, the temperature is raised higher than in the primary drying phase, and can even be above , to break any physico-chemical interactions that have formed between the water molecules and the frozen material. Usually the pressure is also lowered in this stage to encourage desorption (typically in the range of microbars, or fractions of a pascal).
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Coal bed gas content measurements are commonly used in mine safety as well as coal bed methane resource assessment and recovery applications. Gas content determination techniques generally fall into two categories: (1) direct methods which actually measure the volume of methane released from a coal sample sealed into a desorption canister and (2) indirect methods based on empirical correlations, or laboratory derived sorption isotherm methane storage capacity data. Laboratory sorption isotherms provide information about the storage capacity of a coal sampleif these are measured under geological realistic pressure and temperature conditions. Thus, the maximum gas content which can be expected for methane recovery can be assessed from such laboratory isotherm measurements.
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Phase inversion membranes are typically characterized by their mean pore diameter and pore diameter distribution. This can be measured using a number of established analytical techniques such as the analysis of gas adsorption-desorption isotherms, porosimetry, or more niche approaches such as Evapoporometry. A Scanning electron microscope (SEM) can be used to characterize membranes with larger pore sizes, such as microfiltration and ultrafiltration membranes, while Transmission electron microscopy (TEM) can be used for all membrane types, including small pore membranes such as nanofiltration and reverse osmosis, though optical techniques tend to analyze only a small sample area that may not be representative of the sample as a whole.
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Stratification increases between these warmer, less-saline vortices and the surrounding waters by effectively depressing background lines of constant temperature (isotherms) and salinity (isohalines) (shown in figure). This makes them an ideal vehicle to transport coastal water properties into the Gulf of Alaska because of reduced mixing with surrounding waters. As Haida eddies break away from the coast into the subpolar gyre, they transport water properties such as temperature, salinity and kinetic energy. A common water mass in the area is the Pacific Subarctic Upper Water (PSUW) mass with conservative (constant through time and space) properties of salinity (32.6-33.6 psu) and temperature (3-15 °C).
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The mean isotherm in July, marked by the red line, is commonly used to define the border of the Arctic region An isotherm (from or thermē, meaning 'heat') is a line that connects points on a map that have the same temperature. Therefore, all points through which an isotherm passes have the same or equal temperatures at the time indicated. An isotherm at 0 °C is called the freezing level. The term was coined by the Prussian geographer and naturalist Alexander von Humboldt, who as part of his research into the geographical distribution of plants published the first map of isotherms in Paris, in 1817.
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Master curves for the instantaneous modulus E' and the loss factor tanδ as a function of frequency. The data have been fit to a polynomial of degree 7. The principle of time- temperature superposition requires the assumption of thermorheologically simple behavior (all curves have the same characteristic time variation law with temperature). From an initial spectral window [ω1, ω2] and a series of isotherms in this window, we can calculate the master curves of a material which extends over a broader frequency range. An arbitrary temperature T0 is taken as a reference for setting the frequency scale (the curve at that temperature undergoes no shift).
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Temperatures are relatively cold for its latitude due to the cold Malvinas Current and the high altitude. For example, in Tierra del Fuego temperatures are colder than at equal latitudes in the northern hemisphere in Europe since they are influenced by the cold Malvinas Current rather than the warm North Atlantic Current. A characteristic of the temperature pattern is the NW–SE distribution of isotherms due to the presence of the Andes. The warmest areas are in northern parts of Río Negro and Neuquén Provinces where mean annual temperatures range from , while the coldest are in western Santa Cruz and Tierra del Fuego Provinces where mean annual temperatures range from .
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The erosion and exhumation are now concentrated on the southern portion of the mountain range which produces young cooling ages associated with the current tectonic aneurysm center. Young detrital zircon fission track dating (240 °C ± 40 °C) and apatite fission track and uranium -thorium/ helium (110 °C ± 10 °C) cooling ages of sediments in glacial catchment areas support the theory of erosive influence on the St. Elias tectonic system. Rates of exhumation were inferred by calculating the difference between detrital zircon and apatite ages in sediments. The smaller the difference between zircon and apatite ages represents a faster movement of material through the isotherms and faster cooling.
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In contrast to elution chromatography, solutes separated in displacement mode form sharp-edged zones rather than spreading peaks. Zone boundaries in displacement chromatography are self-sharpening: if a molecule for some reason gets ahead of its band, it enters a zone in which it is more strongly retained, and will then run more slowly until its zone catches up. Furthermore, because displacement chromatography takes advantage of the non-linearity of the isotherms, loadings are deliberately high; more material can be separated on a given column, in a given time, with the purified components recovered at significantly higher concentrations. Retention conditions can still be adjusted, but the displacer controls the migration rate of the solutes.
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In a weather map as the one to the right, a col is a region where the position of highs (H) and lows (L) produces a convergence or divergence of the airflow; this includes 2 juxtaposed highs and 2 juxtaposed lows. This pattern packs isotherms and moisture: warm air is advected from the South (TI) while cold air comes from the North (PI) at the point called Z. Then the flow spread the airmass parallel from one to the other forming a stationary front. Any other arrangements that permits confluence of the air flow leads to the formation of a col. In any case, the col is always identified as an area of slack pressure.
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He was among the first to realise and exploit the power of statistical mechanical treatments for the adsorption of gases and liquids in nano-porous materials (such as carbons, silicas and metal-organic framework materials). Such adsorption processes are central to many separation and purification processes, as well as catalysis. The density functional theory method developed by Gubbins and coworkers is now universally used in analysing adsorption isotherms to calculate pore size distributions and porosity of nano-porous materials. More recently he has made major contributions to the characterisation of amorphous porous materials through application of statistical mechanical methods, and to the understanding of diffusion processes and chemical reactions in these materials.
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Satellite imagery has been used to identify thermal bars using their thermal characteristics as well as the concentration of suspended materials on their shoreward side, typically due to surface runoff to the lake. Isotherms on the stratified side of the thermal bar slope away from the bar, producing a pressure gradient force that when balanced by the Coriolis force produces a cyclonic coastal geostrophic current that transports water and suspended matter along the shore. The thermal bar phenomena was first described by François-Alphonse Forel in his study of Lac Leman. Additional studies have been carried out in Lake Ladoga,S. S. Zilitinkevich, K. D. Kreiman, and A. Yu. Terzhevik, “The Thermal Bar,” Journal of Fluid Mechanics 236, no. 1 (1992): 27-42.
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The isotherms are straight and vertical, isobars are straight and horizontal and dry adiabats are also straight and have a 45 degree inclination to the left while moist adiabats are curved. Wind barbs are often plotted at the side of the diagram to indicate the winds at different heights they are used to save space with symbols to help in charts. However, using this configuration sacrifices the equal-area property of the original Clausius–Clapeyron relation requirements between the temperature of the environment and the temperature of a parcel of air lifted/lowered. Although it permits to analyze the cloud cover and the stability of the airmass, it thus does not permit to calculate the Convective Available Potential Energy (CAPE).
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The temperature, humidity, and wind on aeroclimatic maps may apply either to standard altitudes or to the main isobaric surfaces. Isolines are drawn on maps of such climatic features as the long-term mean values (of atmospheric pressure, temperature, humidity, total precipitation, and so forth) to connect points with equal values of the feature in question—for example, isobars for pressure, isotherms for temperature, and isohyets for precipitation. Isoamplitudes are drawn on maps of amplitudes (for example, annual amplitudes of air temperature—that is, the differences between the mean temperatures of the warmest and coldest month). Isanomals are drawn on maps of anomalies (for example, deviations of the mean temperature of each place from the mean temperature of the entire latitudinal zone).
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Isohyetal map of precipitation Meteorological contour lines are based on interpolation of the point data received from weather stations and weather satellites. Weather stations are seldom exactly positioned at a contour line (when they are, this indicates a measurement precisely equal to the value of the contour). Instead, lines are drawn to best approximate the locations of exact values, based on the scattered information points available. Meteorological contour maps may present collected data such as actual air pressure at a given time, or generalized data such as average pressure over a period of time, or forecast data such as predicted air pressure at some point in the future Thermodynamic diagrams use multiple overlapping contour sets (including isobars and isotherms) to present a picture of the major thermodynamic factors in a weather system.
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It has been observed that the value of Ψw decreases as the cell becomes more dehydrated, but scientists have speculated whether this value will continue to decrease but never fall to zero, or if the value can be less than zero. There have been studies which show that negative cell pressures can exist in xerophytic plants, but a paper by M. T. Tyree explores whether this is possible, or a conclusion based on misinterpreted data. In his paper, he concludes that by miscategorizing "bound" and "free" water in a cell, researchers that claimed to have found negative turgor pressure values were incorrect. By analyzing the isotherms of apoplastic and symplastic water, he shows that negative turgor pressures cannot be present within arid plants due to net water loss of the specimen during droughts.
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Together they define the critical point of a fluid above which distinct liquid and gas phases of a given fluid do not exist. The pressure-volume-temperature (PVT) data for real gases varies from one pure gas to another. However, when the compressibility factors of various single-component gases are graphed versus pressure along with temperature isotherms many of the graphs exhibit similar isotherm shapes. In order to obtain a generalized graph that can be used for many different gases, the reduced pressure and temperature, P_r and T_r, are used to normalize the compressibility factor data. Figure 2 is an example of a generalized compressibility factor graph derived from hundreds of experimental PVT data points of 10 pure gases, namely methane, ethane, ethylene, propane, n-butane, i-pentane, n-hexane, nitrogen, carbon dioxide and steam.
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In climate classification, three isotherms means that delineate between hot and cold semi-arid climates — the 18 °C average annual temperature or that of the coldest month (0 °C or −3 °C), the warm side of the isotherm of choice defining a BSh climate from the BSk on the cooler side. As a result of this, some areas can have climates that are classified as hot or cold semi-arid depending on the isotherm used. One such location is San Diego, California (at its main airport), which has cool summers for the latitude due to prevailing winds off the ocean (so the average annual temperature is below 18 °C) but mild winters (average temperature in January, 14 °C, and closer to the 18.0 °C isotherm that separates tropical and subtropical climates than to the 0 °C or −3 °C isotherm for the coldest month that separates temperate and continental climates).
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