
	Where results make sense

Topic: Critical pressure

Related Topics

Critical temperature

Critical point

Pressure

Azeotrope

Ideal gas

Law of definite composition

Molecule

Distillation

Xenon

Critical properties

In the News (Fri 17 Feb 12)

EXECUTIVE POWER

Iran

ANALYSIS

Pakistan

Family compact

	Critical Temperature and Pressure (Site not responding. Last check: 2007-10-20)
		The critical temperature of a substance is the temperature at and above which vapor of the substance cannot be liquefied, no matter how much pressure is applied.
		C (the critical temperature for water), only water vapor exists in the tube.
		The critical pressure of a substance is the pressure required to liquefy a gas at its critical temperature.
	www.chem.purdue.edu /gchelp/liquids/critical.html (96 words)

	Critical temperature - Wikipedia, the free encyclopedia
		The critical pressure is the vapor pressure at the critical temperature.
		The critical molar volume is the volume of one mole of material at the critical temperature and pressure.
		Critical properties vary from material to material, just as is the case for the melting point and boiling point.
	en.wikipedia.org /wiki/Critical_temperature (397 words)

	Critical point (thermodynamics) - Wikipedia, the free encyclopedia
		The critical point in a phase diagram is at the high-temperature extreme of the liquid-gas phase boundary.
		Critical variables are useful for rewriting a varied equation of state into one that applies to all materials.
		However, in some non-equilibrium systems the critical point is an attractor of the dynamics in a manner that is robust with respect to system parameters, a phenomenon referred to as self-organized criticality.
	en.wikipedia.org /wiki/Critical_point_(chemistry) (390 words)

	Critical phenomena Summary
		The critical pressure is the amount of pressure required to liquefy water at the critical temperature.
		Critical phenomena include scaling relations among different quantities, power-law divergences of some quantities (such as the magnetic susceptibility in the ferromagnetic phase transition) described by critical exponents, universality, fractal behaviour, ergodicity breaking.
		The critical behavior is often different from the mean-field approximation which is valid away from the phase transition, since the latter neglects correlations, which become increasingly important as the system approaches the critical point where the correlation length diverges.
	www.bookrags.com /Critical_phenomena (1651 words)

	Properties of Liquids
		Liquids boil at the temperature at which the vapor pressure is equal to the pressure on the liquid from its surroundings.
		The existence of a critical temperature was discovered by Thomas Andrews in 1869 while studying the effect of temperature and pressure on the behavior of carbon dioxide.
		The critical temperatures, critical pressures, and boiling points of a number of gases are given in the table below.
	chemed.chem.purdue.edu /genchem/topicreview/bp/ch14/property.php (1794 words)

	Method for producing carbon dioxide from subterranean formations - Patent 4235289
		By so boosting the pressure within the well, the carbon dioxide will be produced at the surface at a pressure greater than the critical pressure of the produced carbon dioxide, thereby insuring the carbon dioxide will be in a single phase, supercritical state.
		The carbon dioxide arrives at the surface at a pressure and temperature greater than the critical pressure and temperature of the produced carbon dioxide, thereby insuring that the carbon dioxide is produced in a single phase, supercritical state.
		At point B, pump means 12 boosts the pressure, and hence, the temperature of the carbon dioxide to point C (outlet of pump means 12) from which it flows upward through tubing 13 to point D (surface), arriving at point D at a pressure and temperature still well within the single phase supercritical region.
	www.freepatentsonline.com /4235289.html (2788 words)

	ProSciTech - Critical Point Drying - a technical brief, ProSciTech Microscopy Plus Web Catalogue & Laboratory Supplies, ...
		C Isothermal at low applied pressure, the C0 is gaseous (Vapour) and generally exhibits the characteristics of a gas (Boyles Law) over the range from 'r' to 's'.
		From the point 's' a very slight increase in pressure corresponds to a change from the vapour state to the liquid state, which is the phenomenon of saturation.From 's' to 't' the pressure is virtually constant while the volume is decreasing and at 't' the substance is all liquid.
		If a liquid was heated in a closed system so that the Critical Pressure could be attained, at the Critical Temperature, any visible meniscus would disappear, the surface tension would be zero and it would not be possible to distinguish between the properties of a liquid or gas.
	www.proscitech.com.au /catalogue/notes/cpd.htm (1436 words)

	Angiology - Coronary artery bypass graft critical occlusion pressure measure...
		Angiology - Coronary artery bypass graft critical occlusion pressure measure...
		Coronary artery bypass graft critical occlusion pressure measurement is discussed
		Critical occlusion pressure in arterial grafts should be used as the effective downstream pressure when calculating coronary perfusion pressure.
	www.newsrx.com /library/newsletters/Blood-Weekly/274485.html (193 words)

	Critical Point Drier
		Critical Point Drying is so named as it includes, as part of its process, the occurrence known as the continuity of state for which there is no apparent difference between the liquid and gas state of a medium, the surface tension between this interface reducing to zero.
		The EMS 850 Critical Point Drier is designed for use with CO, having first replaced any water in the specimen by a series of dehydration, often in the same fluid such as Acetone, which will also be the intermediate fluid.
		This ensures the critical point is accurately obtained, avoiding excess pressures or temperatures, or the need to rely on pressure relief valves to control pressure during the heating cycle.
	www.emsdiasum.com /microscopy/products/equipment/critical_point_drier.aspx?mm=19 (434 words)

	Development of a Critical Air Flow Venturi for Air Sampling
		The critical pressure drop is lower and the discharge coefficient is higher for the critical venturi with a curved entrance.
		The critical pressure drop at a stable airflow for a critical plate orifice is at 47 kPa; for a non-optimized critical venturi it is at 23 kPa.
		The critical pressure drop of the optimized critical venturi at a stable airflow is lower (approximately 9 kPa) and the pressure recovery efficiency is higher (90%).
	www.age.uiuc.edu /bee/Research/multi-sampler/multi2.htm (3454 words)

	CRITICAL PRESSURE
		In rocketry, the pressure in the nozzle throat for which the isentropic weight flow rate is a maximum.2.
		The pressure of a gas at critical point, which is the highest pressure under which a liquid can exist in equilibrium with its vapor.
		The pressure required to condense a gas at the critical temperature, above which, regardless of pressure, the gas cannot be liquefie.
	www.websters-online-dictionary.org /definition/english/cr/critical+pressure.html (281 words)

	Phase Diagrams
		At moderate temperatures and high pressure, (liquid) water is the stable phase, and at high temperature and low pressure, (gas) vapor is the stable phase.
		The temperature of 647 K is called the critical temperature, and the vapor pressure at this temperature is called the critical pressure.
		The critical temperature for carbon dioxide is 31.1°C, and the critical pressure is 73 atm.
	www.science.uwaterloo.ca /~cchieh/cact/c123/phasesdgm.html (1045 words)

	Miscibility Critical Pressures in Monolayers of Ternary Lipid Mixtures -- Keller et al. 79 (4): 2033 -- Biophysical ...
		Miscibility critical pressure is a sensitive function of the lipids in the monolayer.
		The critical pressure of 67% di(24:1)PC and 33% Dchol is extrapolated from Fig.
		is the (binary) critical pressure of a mixture of components i and j and a'
	www.biophysj.org /cgi/content/full/79/4/2033 (4815 words)

	C - Glossary of chemical terms
		Critical pressure is the pressure of a fluid in its critical point; i.e.
		Critical temperature is the temperature of the liquid-vapour critical point, that is, the temperature above which a gas cannot be liquefied by an increase of pressure.
		Critical volume is the volume of a fixed mass of a fluid at critical temperature and pressure.
	www.ktf-split.hr /periodni/en/abc/c.html (1906 words)

	Double wall plug control valve - Patent 4041982
		As is known, in the case of a gas flow, a critical pressure ratio (i.e.
		Experiments have shown that pressure ratio quantities across a given restriction to flow is the predominant factor in producing noise in gas service and in producing both noise and cavitation damage in liquid service.
		For purposes of illustration, the critical pressure ratios F.sub.f for water relative to vapor pressure are shown graphically in FIG.
	www.freepatentsonline.com /4041982.html (2593 words)

	Critical pressure and temperature (Site not responding. Last check: 2007-10-20)
		The critical temperature of a liquid is that temperature beyond which the liquid cannot exist, no matter how much pressure is placed on it.
		The pressure that is needed to cause the gas to condense at the critical temperature is the critical pressure.
		At room pressure, propane is a gas, but it can be easily liquified by placing it in a container and pressurizing it.
	www.cartage.org.lb /en/themes/sciences/chemistry/Miscellenous/Helpfile/LiquidandSolid/Criticalpressure.htm (201 words)

	Flow Glossary by Lenox Laser the leader in small hole technology
		Gauge Pressure - is pressure measured above atmospheric pressure, while absolute pressure is pressure measured above perfect vacuum as a base.
		Reference to vacuum conditions is often made by expressing the absolute pressure in inches of mercury; also millimeters of mercury and microns of mercury.
		Barometric pressure, bernoulli, bernoulli theorem, critical flow, critical pressure, critical pressure ratio, darcy formula, darcy,flow diameter, gas constant, gauge pressure, pressure, energy.
	www.lenoxlaser.com /tech_ref/flow_glossary.html (443 words)

	Nozzle
		The flow rate varies linearly with the upstream pressure and is not affected by downstream pressure fluctuation or changes by virtue of sonic velocity existing at the throat.
		Critical flow is characterized by the gas velocity in the nozzle throat being precisely equal to the speed of sound.
		This is to insure that a critical pressure ratio between the inlet and exit of 1.2 or greater exists.
	www.flow-dyne.com /nozzle.htm (1226 words)

	Brazilian Journal of Chemical Engineering - Calculation of mixture critical diagrams using an equation of state based ... (Site not responding. Last check: 2007-10-20)
		Several qualitative aspects of the critical curves, such as maxima and minima in critical pressure, and minima in critical temperature, could be predicted using the MTC lattice EOS.
		Calculations of mixture critical points represent a severe test for equations of state (EOS) because of the complex types of phase diagrams that are experimentally observed for several mixtures (van Konynenburg and Scott, 1980; van Pelt, 1992).
		The discontinuity in the gas-liquid critical line and the existence of a high pressure critical branch that starts at the critical point of water were correctly predicted by the MTC lattice EOS.
	www.scielo.br /scielo.php?script=sci_arttext&pid=S0104-66322000000400040&lng=es&nrm=iso (3397 words)

	Critical Pressure Monitoring (Site not responding. Last check: 2007-10-20)
		Use Radcom "Critical pressure loggers" to monitor your water pressure at critical points across your distribution pipeline.
		On occurrence of a high or low pressure condition the logger can alarm out and alert you immediatley of the problem.
		Critical Pressure Loggers are typically Pressure only loggers, but you will see from the graph that Pressure is directly influenced by water flow, and the diurnal profile is necessary to determine an acceptable minimum pressure for a particular time of the day or night.
	www.radcom.co.uk /CriticalPressureMonitoring.html (168 words)

	CiteULike: Spectral analysis of blood pressure and heart rate variability in evaluating cardiovascular regulation. A ... (Site not responding. Last check: 2007-10-20)
		Blood pressure variability includes rhythmic and nonrhythmic fluctuations that, with the use of spectral analysis, appear as clear peaks or broadband power, respectively.
		This review offers a concise and critical description of the spectral methods most commonly used (fast Fourier transform versus autoregressive modeling, time-varying versus broadband spectral analysis) and an evaluation of their advantages and disadvantages.
		In particular, the assessment of blood pressure and heart rate spectra aimed at providing indexes of autonomic cardiovascular modulation is discussed.
	www.citeulike.org /user/abelmagalhaes/article/524222 (299 words)

	Spartanburg SC \| GoUpstate.com \| Spartanburg Herald-Journal (Site not responding. Last check: 2007-10-20)
		In this definition, there is a critical pressure and an associated critical density, and when nuclear matter (made of protons and neutrons) is compressed beyond this density, the protons and neutrons dissociate into quarks, yielding quark matter (probably strange matter).
		In this definition, the critical pressure is zero: the true ground state of matter is always quark matter.
		It seems plausible that the transition to quark matter will already have occurred when the separation between the nucleons becomes much smaller than their size, so the critical density must be less than about 100 times nuclear saturation density.
	www.goupstate.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=strange_matter (1100 words)

	Chemical process engineering - Orifice Plate Critical Pressure Ratio
		Critical pressure drop is dependant on beta ratio and specific heat ratio.
		The throughput continues to rise as the downstream pressure is reduced (and the vena contracta area increases).
		Pressure recovery is simply the conversion of kinetic energy to pressure based on the change of velocity from the orifice to the mean downstream pipe velocity and is easy to calculate.
	www.eng-tips.com /viewthread.cfm?qid=51260 (2392 words)

	critical pressure definition - Dictionary - MSN Encarta
		critical pressure definition - Dictionary - MSN Encarta
		Search for "critical pressure" in all of MSN Encarta
		pressure at critical point: the pressure of a substance when at the critical point between liquid and vapor phases
	encarta.msn.com /encnet/features/dictionary/DictionaryResults.aspx?refid=561531744 (83 words)

	Chemical process engineering - Vapour pressure and critical temperature
		When isothermally removing gas, the total pressure in the well drops and part of the nat-gas (butanes and heavier) liquefies, a fact that may lead to a reduction in the production of the well when the liquid is trapped in the sands.
		The upstream pressure of your control valve is not equivalent to the vapor pressure of the fluid.
		Usually "vapor pressure" refers to a the pressure imparted by a liquid in a tank or vessel and is a function of temperature.
	www.eng-tips.com /viewthread.cfm?qid=70867 (1083 words)

Try your search on: Qwika (all wikis)