William Rowan Hamilton: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
← Older editNewer edit →
en>Isarra (HG)
m Reverted edits by 87.36.36.5 (talk): editing tests (HG)
en>Wavelength
inserting 1 hyphen: —> "three-dimensional"—wikt:three-dimensional
Line 1: Line 1:
[[File:Vapor pressure.svg|thumb|The picture shows the particle transition, as a result of their vapor pressure, from the liquid phase to the gas phase and converse.]]
'''Vapor pressure''' or '''equilibrium vapor pressure''' is defined as the [[pressure]] exerted by a [[vapor]] in [[thermodynamic equilibrium]] with its [[Condensation|condensed]] [[Phase (matter)|phase]]s (solid or liquid) at a given temperature in a [[Thermodynamic_system#Closed_system|closed system]]. The equilibrium vapor pressure is an indication of a liquid's [[evaporation]] rate. It relates to the tendency of particles to escape from the liquid (or a solid). A substance with a high vapor pressure at normal temperatures is often referred to as ''[[volatility (chemistry)|volatile]]''.


The vapor pressure of any substance increases non-linearly with temperature according to the [[Clausius–Clapeyron relation]]. The [[atmospheric pressure]] [[boiling point]] of a liquid (also known as the [[normal boiling point]]) is the temperature at which the vapor pressure equals the ambient atmospheric pressure. With any incremental increase in that temperature, the vapor pressure becomes sufficient to overcome [[atmospheric pressure]] and lift the liquid to form vapor bubbles inside the bulk of the substance. [[liquid bubble|Bubble]] formation deeper in the liquid requires a higher pressure, and therefore higher temperature, because the fluid pressure increases above the atmospheric pressure as the depth increases.


The vapor pressure that a single component in a mixture contributes to the total pressure in the system is called [[partial pressure]]. For example, air at sea level, and saturated with water vapor at 20 °C, has partial pressures of about 23 mbar of [[water]], 780 mbar of [[nitrogen]], 210 mbar of [[oxygen]] and 9 mbar of [[argon]].
Biodiesel is the identify of a thoroughly clean burning alternative gasoline created from domestic, renewable assets this sort of as vegetable oils or other renewable means.<br>It can be created from soy or canola oil, squander cooking oil, and even animal fat. Biodiesel is made up of no petroleum, but it can be blended at any stage with petroleum diesel to develop a biodiesel mix. It can be made use of in compressionignition (diesel) engines with no major modifications.<br><br>Biodiesel is uncomplicated to use, biodegradable, nontoxic, and fundamentally no cost of sulfur and aromatics. Biodiesel can be distributed applying today's infrastructure, and its use and generation are escalating quickly. Gas stations are commencing to make biodiesel accessible to customers, and a developing number of transport fleets use it as an additive in their gasoline.<br><br>Biodiesel is attaining acceptance for the reason that it really is excellent for the setting and can be utilized in virtually any diesel motor vehicle developed in the previous 10 decades. The creation of biodiesel is an industry in its infancy in just the United States , even however the marketplace for the different fuel has been a mainstay in Europe and South The usa for years.<br><br>It is increasing swiftly all more than the earth due to expanding concerns about concentrations of environmental pollution and minimal offer of vitality resources.<br>In 2000, biodiesel grew to become the only substitute gas in the state to have properly completed the EPA-required Tier I and Tier II overall health outcomes testing underneath the Cleanse Air Act. These independent assessments conclusively reveal biodiesels' considerable reduction of virtually all regulated emissions, and showed biodiesel does not pose a danger to human well being.<br><br>A US Department of Vitality study showed that the output and use of biodiesel, compared to petroleum diesel, resulted in a 78.five% reduction in carbon dioxide emissions. Moreover, biodiesel has a good electricity equilibrium. For each and every unit of electricity required to produce a gallon of biodiesel, three.24 units of electricity are gained.<br>Many federal companies, which includes the Section of Defense (DoD), are picking to use biodiesel or biodiesel blends.<br><br>There are some downsides to biodiesel well worth mentioning. Biodiesel is generally additional costly to acquire than petroleum diesel but this differential may well diminish owing to economies of scale, the increasing cost of petroleum and govt tax subsidies. Other than increased charges, biodiesel coagulates at chilly temperatures, so cars have to be retrofitted with a fuel-heating process.<br><br>And despite the fact that biodiesel vehicles are cleaner than regular diesel in many respects, they nevertheless emit about the very same amount of money of nitrogen oxide, one of the principal components of smog. Continue to, numerous are confident that the pros of biodiesel far outweigh the down sides.<br>Chevron just lately gave $25 million to the University of California, Davis (UC Davis) to go on research into biofuel processing technology.<br><br>Chevron also invested in a Texas biodiesel plant, which will give them 22% possession and strengthen U.S. biodiesel production by a lot more than 50%.<br>South Africa-based Conventional Lender has entered the biodiesel sector with an $eight million fairness financial commitment in Biodiesel Strength Trading.<br>Environmentally-acutely aware celebrities these kinds of as Willie Nelson, Jack Johnson and Mandy Moore, are also supporting and investing in biodiesel. Willie Nelson even started out his have biodiesel firm, aptly titled BioWillie.<br><br>In the United States, 34 out of the 50 states are now making biodiesel fuel, with Maryland just lately included to the listing.<br>So how can you capitalize on the momentum of biodiesel, make a healthy return and enable to preserve the ecosystem in the approach? We have profiled just one of our beloved biodiesel plays under.<br>Nova Biosource Fuels (Ticker: NVAO.OB)<br>Nova Biosource Fuels, which was formerly Nova Vitality Holding, is an vitality organization that synthesizes and distributes renewable fuel goods. Nova's initial emphasis is to construct and operate quite a few biodiesel refineries with generation ability of more than 300 million gallons of fuel on an once-a-year foundation.<br><br>Within a few years Nova intends to construct, using proprietary patented-method technology, 7 biodiesel refineries ranging from twenty- to fifty-million gallons for each year in production potential. Nova has presently taken concrete actions toward the realization of these ambitions:<br>Nova concluded a personal placement in July for in excess of $18 million. These money will be employed to establish and run two to four biodiesel refineries with a production capacity of amongst one hundred twenty to 240 million gallons of biodiesel fuel for each calendar year. This news is really good as it demonstrates institutions and big buyers believe that the corporation to be a strong expense.<br><br><br>But the big news propelling Nova's stock value is a just lately-inked deal with ConAgra. ConAgra is 1 of North America's major packaged food items businesses. In July, Nova signed a feedstock provide and biodiesel product sales agreements with ConAgra Trade Group. The agreements present that ConAgra Trade Group will procure the vegetable oil and animal- centered feedstock specifications for the Nova-owned biodiesel refinery, as properly as promote the biodiesel gasoline and take care of the logistics for the facility.<br><br>Building on the partnership with ConAgra, Nova a short while ago signed a biodiesel profits agreement for Nova's sixty million gallon per yr biodiesel facility to be positioned in Seneca, Illinois. ConAgra Trade Team will provide advertising and outbound logistics solutions for the facility as section of the agreement.<br>Nova expects the Seneca refinery to be open up in the summer time of 2007.<br><br>Operational Highlights consist of the very first 10 million gallon for each year biodiesel refinery staying developed in Clinton County, Iowa nearing completion. This facility is targeted for completion in the coming months.<br>The 2nd refinery is becoming developed near DeForest, Wisconsin, and the facility will be wholly owned by Anamax Vitality Products and services. Nova's agreement with Anamax delivers for the structure and building of a 20 million gallon per calendar year biodiesel facility on the premises of an Anamax-owned rendering plant.<br><br>The targeted completion day of this facility is January 2007.<br>The third refinery is getting crafted for Scott Petroleum Corp. and the arrangement presents for the design and style and design of a twenty million gallon per calendar year biodiesel refinery found in Greenville, Mississippi. Nova by now has an arrangement with Scott Petroleum to invest in fifty p.c of this facility's generation for ten decades at roughly the production cost in trade for initial and deferred payments meant to reimburse Scott Petroleum for the incremental building prices connected with increasing the ability from ten to 20 million gallons per calendar year.<br><br>The targeted completion date for this facility is anticipated to be in early 2007.<br>Nova has a proprietary, patented biodiesel manufacturing technologies, formulated by Nova Biosource Fules, which is wholly-owned by Nova Energy Keeping.  When you cherished this informative article and you would like to receive guidance relating to [http://nova3hackapk.getresponsepages.com nova 3 mod] i implore you to visit our own web site. This technologies lets Nova to cut down processing costs by up to 35% and general fuel manufacturing expenditures by as much as 20% from standard field practices.<br><br>This aggressive benefit final results in lessen manufacturing expenses, more rapidly facility permitting, and minimum environmental effect owing to the absence of air and drinking water squander streams.<br>Nova features seasoned management, like CEO Kenneth Bern who served as President of Texaco Saudi, Inc., involving 1981-1984, as Vice Chairman and Taking care of Director of Texaco Nigeria Constrained from 1984 by means of 1989, and as President of Texaco Brazil from 1989 by means of 1994.<br><br>COO Jody Powers was the previous president of Halliburton Vitality Expert services, in which he labored for 35 decades. Nova has also stacked their board with business industry experts and expert veterans in the vitality industry. Their steering and their contacts should allow Nova to take benefit of alternatives moving ahead.<br><br>Softer oil prices cut down fascination in option resources of vitality -- and their stocks. Nova's stock value experienced together with the recent decline in crude oil price ranges, but has considering the fact that been rebounded strongly. Soon after diving underneath $three.00, Nova's stock has immediately shot up to $four.00, predominantly on news of the ConAgra deal.<br><br>Nova closed now up eleven% on volume of practically triple the normal. We see Nova breaking their all-time significant of $4.forty in the coming months, giving the prospective for a rapid 10% revenue. However, Nova should be seen as a long-expression perform, as current refinery building and board appointments has shown motivation to starting to be a major biodiesel producer.<br><br>Please observe that continuing weak point in oil selling prices will suppress any value innovations for Nova. We are of the impression that oil costs are headed again previously mentioned $70 by calendar year finish and consider this will enable propel Nova's share price to all-time highs. If you disagree and feel oil will carry on down, alternate electrical power companies are not a prudent financial commitment for you.<br><br>As normally, you should really do your have thanks diligence, in particular with bulletin board stocks that have a larger danger profile.<br>Disclaimer: The creator does not presently very own any stock in Nova Biosource Fuels and was not compensated in any way to publish this write-up.
 
==Measurement and units==
Vapor pressure is measured in the standard units of [[pressure]]. The [[International System of Units]] (SI) recognizes pressure as a [[SI derived unit|derived unit]] with the dimension of force per area and designates the [[pascal (unit)|pascal]] (Pa) as its standard unit. One pascal is one [[newton (unit)|newton]] per [[square meter]] (N·m<sup>−2</sup> or kg·m<sup>−1</sup>·s<sup>−2</sup>).
 
Experimental measurement of vapor pressure is a simple procedure for common pressures between 1 and 200 kPa.<ref>{{cite web|url=http://www.capec.kt.dtu.dk/documents/overview/Vapor-pressure-Ruzicka.pdf|title=Vapor Pressure of Organic Compounds. Measurement and Correlation|author=K. Růžička, M. Fulem, V. Růžička}}</ref> Most accurate results are obtained near the boiling point of substances and large errors result for measurements smaller than {{gaps|1|kPa}}. Procedures often consist of purifying the test substance, isolating it in a container, evacuating any foreign gas, then measuring the equilibrium pressure of the gaseous phase of the substance in the container at different temperatures. Better accuracy is achieved when care is taken to ensure that the entire substance and its vapor are at the prescribed temperature. This is often done, as with the use of an [[isoteniscope]], by submerging the containment area in a liquid bath.
 
==Estimating vapor pressures with Antoine equation==
 
The [[Antoine equation]] <ref name=frostburg>[http://antoine.frostburg.edu/chem/senese/101/liquids/faq/antoine-vapor-pressure.shtml What is the Antoine Equation?] (Chemistry Department, [[Frostburg State University]], [[Maryland]])</ref><ref name=Sinnot>{{cite book|author=R.K.Sinnot|title=[http://books.google.ca/books?id=DJaxUL3numgC&pg=PA331&lpg=PA331&dq=antoine+equation+constants&source=bl&ots=2c0cqzbR0t&sig=YPuvrW2kWnWP2s4QvY9TTpxGgNM&hl=en&sa=X&ei=widrUcu9Cce0qgHq24CgCA&ved=0CGcQ6AEwBzgK#v=onepage&q=antoine%20equation%20constants&f=false Chemical Engineering Design]|edition=4th|publisher=Butterworth-Heinemann|year=2005|page=331|isbn=0-7506-6538-6}}</ref> is a mathematical expression  of the relation between the vapor pressure and the temperature of pure liquid or solid substances. The basic form of the equation is:
 
:<math>\log P = A-\frac{B}{C+T}</math>
 
and it can be transformed into this temperature-explicit form:
 
:<math>T = \frac{B}{A-\log P} - C</math>
 
where: <span style="vertical-align:+12%;"><math>P</math></span> is the absolute vapor pressure of a substance<br>
:&nbsp; &nbsp; <span style="vertical-align:+15%;"><span style="vertical-align:+12%;"><math>T</math></span> is the temperature of the substance</span>
:&nbsp; &nbsp; <span style="vertical-align:+12%;"><math>A</math></span>, <span style="vertical-align:+12%;"><math>B</math></span> and <span style="vertical-align:+12%;"><math>C</math></span> are substance-specific coefficients (i.e., constants or parameters)
:&nbsp; &nbsp; <span style="vertical-align:-30%;"><math>\log</math> is typically either <math>\log_{10}</math> or <math>\log_e</math></span><ref name=Sinnot/>
 
A simpler form of the equation with only two coefficients is sometimes used:
 
:<math>\log P = A-\frac{B}{T}</math>
 
which can be transformed to:
 
:<math>T = \frac{B}{A-\log P}</math>
 
Sublimations and vaporizations of the same substance have separate sets of Antoine coefficients, as do components in mixtures.<ref name=frostburg/> Each parameter set for a specific compound is only applicable over a specified temperature range. Generally, temperature ranges are chosen to maintain the equation's accuracy of a few up to 8-10 percent.  For many volatile substances, several different sets of parameters are available and used for different temperature ranges. The Antoine equation has poor accuracy with any single parameter set when used from a compound's melting point to its critical temperature. Accuracy is also usually poor when vapor pressure is under 10 Torr because of the limitations of the apparatus used to establish the Antoine parameter values.
 
The Wagner Equation<ref>{{Citation|last= Wagner|first= W.|title= New vapour pressure measurements for argon and nitrogen and an new method for establishing rational vapour pressure equations|journal= Cryogenics|volume= 13|issue= 8|pages= 470&ndash;482 |year= 1973|doi= }}</ref> gives "one of the best"<ref>Perry's Chemical Engineers' Handbook, 7th Ed. pg 4-15</ref> fits to experimental data but is quite complex.  It expresses reduced vapor pressure as a function of reduced temperature.
 
==Relation to boiling point of liquids==
{{further|Boiling point}}
[[Image:Vapor Pressure Chart.png|thumb|right|301 px|A typical vapor pressure chart for various liquids]]
As a general trend, vapor pressures of liquids at ambient temperatures increase with decreasing boiling points. This is illustrated in the vapor pressure chart (see right) that shows graphs of the '''vapor pressures versus temperatures''' for a variety of liquids.<ref>{{cite book|author=Perry, R.H. and Green, D.W. (Editors)|title=[[Perry's Chemical Engineers' Handbook]]|edition=7th|publisher=McGraw-Hill|year=1997|isbn= 0-07-049841-5}}</ref>
 
For example, at any given temperature, [[methyl chloride]] has the highest vapor pressure of any of the liquids in the chart. It also has the lowest normal boiling point (−24.2&nbsp;°C), which is where the vapor pressure curve of methyl chloride (the blue line) intersects the horizontal pressure line of one atmosphere ([[Atmosphere (unit)|atm]]) of absolute vapor pressure.
 
Although the relation between vapor pressure and temperature is non-linear, the chart uses a logarithmic vertical axis to produce slightly curved lines, so one chart can graph many liquids. A nearly straight line is obtained when the logarithm of the vapor pressure is plotted against 1/(T+230)<ref>{{cite article|author=Dreisbach, R. R. and Spencer, R. S.| title=Infinite Points of Cox Chart Families and dt/dP Values at any Pressure|journal=Industrial and Engineering Chemistry,|volume=41|number=1|page=176|month=January|year=1949}}</ref> where T is the temperature in degrees Celsius. The vapor pressure of a liquid at its boiling point equals the pressure of its surrounding environment.
 
==Liquid mixtures==
[[Raoult's law]] gives an approximation to the vapor pressure of mixtures of liquids. It states that the activity (pressure or [[fugacity]]) of a single-phase mixture is equal to the mole-fraction-weighted sum of the components' vapor pressures:
 
:<math> p_\text{tot} = \sum_i p_i \chi_i \,</math>
 
where '''''p'''''<sub> '''tot'''</sub> is the mixture's vapor pressure, '''''i''''' is one of the components of the mixture and '''''Χ<sub>i</sub>''''' is the [[mole fraction]] of that component in the liquid mixture.  The term '''''p<sub>i</sub>Χ<sub>i</sub>''''' is the partial pressure of component '''''i''''' in the mixture. Raoult's Law is applicable only to non-electrolytes (uncharged species); it is most appropriate for non-polar molecules with only weak intermolecular attractions (such as [[London force]]s).
 
Systems that have vapor pressures higher than indicated by the above formula are said to have positive deviations.  Such a deviation suggests weaker intermolecular attraction than in the pure components, so that the molecules can be thought of as being "held in" the liquid phase less strongly than in the pure liquid.  An example is the [[azeotrope]] of approximately 95% ethanol and water.  Because the azeotrope's vapor pressure is higher than predicted by Raoult's law, it boils at a temperature below that of either pure component.
 
There are also systems with negative deviations that have vapor pressures that are lower than expected.  Such a deviation is evidence for stronger intermolecular attraction between the constituents of the mixture than exists in the pure components.  Thus, the molecules are "held in" the liquid more strongly when a second molecule is present.  An example is a mixture of trichloromethane (chloroform) and 2-propanone (acetone), which boils above the boiling point of either pure component.
 
The negative and positive deviations can be used to determine [[thermodynamic activity]] coefficients of the components of mixtures.
 
==Solids==
[[Image:Vapor Pressure Curve of Liquid and Solid Benzene.png|thumb|300px|Vapor pressure of liquid and solid benzene]]
Equilibrium vapor pressure can be defined as the pressure reached when a condensed phase is in equilibrium with its own vapor. In the case of an equilibrium solid, such as a [[crystal]], this can be defined as the pressure when the rate of [[sublimation (physics)|sublimation]] of a solid matches the rate of deposition of its vapor phase. For most solids this pressure is very low, but some notable exceptions are [[naphthalene]], [[dry ice]] (the vapor pressure of dry ice is 5.73 MPa (831 psi, 56.5 atm) at 20 degrees Celsius, which causes most sealed containers to rupture), and ice.  All solid materials have a vapor pressure. However, due to their often extremely low values, measurement can be rather difficult. Typical techniques include the use of [[thermogravimetry]] and [[gas transpiration]].
 
There are a number of methods for calculating the sublimation pressure (i.e., the vapor pressure) of a solid. One method is to estimate the sublimation pressure from extrapolated liquid vapor pressures (of the supercooled liquid), if the [[Enthalpy of fusion|heat of fusion]] is known, by using this particular form of the [[Clausius–Clapeyron relation]]:<ref name="Moller">Moller B., Rarey J., Ramjugernath D., "Estimation of the vapour pressure of non-electrolyte organic compounds via group contributions and group interactions ", J.Mol.Liq., 143(1), 52-63, 2008</ref>
 
:<math>\ln\,P^S_{solid} = \ln\,P^S_{liquid} - \frac{\Delta H_m}{R} \left( \frac{1}{T} - \frac{1}{T_m} \right)</math>
 
with:
 
{| border="0" cellpadding="1"
|-
!align=right|<math>P^S_{solid}</math> 
|align=left|= Sublimation pressure of the solid component at the temperature <math>T<T_m</math>
|-
!align=right|<math>P^S_{liquid}</math>
|align=left|= Extrapolated vapor pressure of the liquid component at the temperature <math>T<T_m</math>
|-
!align=right|<math>\Delta H_m</math>
|align=left|= Heat of fusion
|-
!align=right|<math>R</math>
|align=left|= [[Gas constant]]
|-
!align=right|<math>T</math>
|align=left|= Sublimation temperature
|-
!align=right|<math>T_m</math>
|align=left|= Melting point temperature
|}
 
This method assumes that the heat of fusion is temperature-independent, ignores additional transition temperatures between different solid phases, and it gives a fair estimation for temperatures not too far from the melting point. It also shows that the sublimation pressure is lower than the extrapolated liquid vapor pressure (Δ''H''<sub>m</sub> is positive) and the difference grows with increased distance from the melting point.
 
==Boiling point of water==
[[Image:Water vapor pressure graph.jpg|thumb|right|Graph of water vapor pressure versus temperature. At the normal boiling point of 100°C, it equals the standard atmospheric pressure of 760 Torr or 101.325 kPa.]]
{{main|Vapor pressure of water}}
Like all liquids, water boils when its vapor pressure reaches its surrounding pressure.  In nature, the atmospheric pressure is lower at higher elevations and water boils at a lower temperature.  The boiling temperature of [[water]] for atmospheric pressures can be approximated by the [[Antoine equation]]:
 
:<math>\log_{10}P = 8.07131 - \frac{1730.63}{233.426 + T_b}</math>
 
or transformed into this temperature-explicit form:
 
:<math>T_b = \frac{1730.63}{8.07131 - \log_{10}P} - 233.426</math>
 
where the temperature <math>T_b</math> is the boiling point in degrees [[Celsius]] and the pressure <math>P_{ } </math> is in [[Torr]].
 
==Dühring's rule==
{{main|Dühring's rule}}
Dühring's rule states that a linear relationship exists between the temperatures at which two solutions exert the same vapor pressure.
 
==Examples==
The following table is a list of a variety of substances ordered by increasing vapor pressure.
{|style="text-align:center;" class="wikitable"
! Substance
! Vapor Pressure<br>(SI units)
! Vapor Pressure<br>(Bar);
! Vapor Pressure<br>(mmHg);
! Temperature
|-
 
| [[Tungsten]]
| 100 Pa
| 0.001
| 0.75
| 3203 °C
|-
 
| [[Ethylene glycol]]
| 500 Pa
| 0.005
| 3.75
| 20 °C
|-
 
| [[Xenon difluoride]]
| 600 Pa
| 0.006
| 4.50
| 25 °C
|-
 
| [[Water]] (H<sub>2</sub>O)
| 2.3 kPa
| 0.023
| 17.5
| 20 °C
|-
 
| [[Propanol]]
| 2.4 kPa
| 0.024
| 18.0
| 20 °C
|-
 
| [[Ethanol]]
| 5.83 kPa
| 0.0583
| 43.7
| 20 °C
|-
 
| [[Methyl isobutyl ketone]]
| 2.66 kPa
| 0.0266
| 19.95
| 25 °C
|-
 
| [[Freon|Freon 113]]
| 37.9 kPa
| 0.379
| 284
| 20 °C
|-
 
| [[Acetaldehyde]]
| 98.7 kPa
| 0.987
| 740
| 20 °C
|-
 
| [[Butane]]
| 220 kPa
| 2.2
| 1650
| 20 °C
|-
 
| [[Formaldehyde]]
| 435.7 kPa
| 4.357
| 3268
| 20 °C
|-
 
| [[Propane]]
| 1.013 MPa
| 10.133
| 7600
| 25.6 °C
|-
 
| [[Carbonyl sulfide]]
| 1.255 MPa
| 12.55
| 9412
| 25 °C
|-
 
| [[Carbon dioxide]]
| 5.7 MPa
| 57
| 42753
| 20 °C
|-
 
|}
 
==Estimating vapor pressure from molecular structure==
Several empirical methods exist to estimate liquid vapor pressure from molecular structure for organic molecules. Some examples are SIMPOL,<ref>{{cite journal|author=J. F. Pankow et al.|title=SIMPOL.1: a simple group contribution method for predicting vapor pressures and enthalpies of vaporization of multifunctional organic compounds|journal=Atmos. Chem. Phys.|volume=8|pages=2773–2796|year=2008|url=http://www.atmos-chem-phys.net/8/2773/2008/acp-8-2773-2008.html}}</ref> the method of Moller et al.,<ref name = "Moller" /> and EVAPORATION.<ref>[http://tropo.aeronomie.be/models/evaporation_run.htm "Vapour pressure of pure liquid compounds. Estimation by EVAPORATION"]</ref><ref>{{cite journal|author=S. Compernolle et al.|title=EVAPORATION: a new vapour pressure estimation method for organic molecules including non-additivity and intramolecular interactions|journal=Atmos. Chem. Phys.|volume=11|pages=9431–9450|year=2011|url=http://www.atmos-chem-phys.net/11/9431/2011/acp-11-9431-2011.html}}</ref>
 
==Meaning in meteorology==
In [[meteorology]], the term ''vapor pressure'' is used to mean the [[partial pressure]] of [[water vapor]] in the atmosphere, even if it is not in equilibrium,<ref>[http://amsglossary.allenpress.com/glossary/search?id=vapor-pressure1 Glossary] (Developed by the [[American Meteorological Society]])</ref> and the ''equilibrium vapor pressure'' is specified otherwise. Meteorologists also use the term ''saturation vapor pressure'' to refer to the equilibrium vapor pressure of water or [[brine]] above a flat surface, to distinguish it from equilibrium vapor pressure, which takes into account the shape and size of water droplets and particulates in the atmosphere.<ref>[http://fermi.jhuapl.edu/people/babin/vapor/index.html A Brief Tutorial] (An article about the definition of equilibrium vapor pressure)</ref>
 
==See also==
* [[Absolute humidity]]
* [[Clausius-Clapeyron relation]]
* [[Partial pressure]]
* [[Relative humidity]]
* [[Relative volatility]]
* [[Raoult's law]]
* [[Saturation vapor density]]
* [[Triple point]]
* [[Vapor-liquid equilibrium]]
* [[Vapour pressure of water|Vapor pressure of water]]
* [[Volatility (chemistry)|Volatility]]
* [[Reid vapor pressure]]
* [[True vapor pressure]]
* [[Vapor pressures of the elements (data page)]]
 
==References==
{{Reflist}}
 
==External links==
*[http://www.engineersedge.com/fluid_flow/fluid_data.htm Fluid Characteristics Chart]
*[http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/vappre.html#c2 Hyperphysics]
*[http://www.ilpi.com/msds/ref/vaporpressure.html MSDS Vapor Pressure]
*[http://www.envmodels.com/freetools.php?menu=pression Online vapor pressure calculation tool (Requires Registration)]
*[http://www.aim.env.uea.ac.uk/aim/ddbst/pcalc_main.php Prediction of Vapor Pressures of Pure Liquid Organic Compounds]
 
[[Category:Thermodynamic properties]]
[[Category:Chemical engineering]]
[[Category:Meteorology]]
[[Category:Gases]]
[[Category:Pressure]]
 
[[fr:Pression de vapeur saturante]]

Revision as of 00:59, 26 February 2014


Biodiesel is the identify of a thoroughly clean burning alternative gasoline created from domestic, renewable assets this sort of as vegetable oils or other renewable means.
It can be created from soy or canola oil, squander cooking oil, and even animal fat. Biodiesel is made up of no petroleum, but it can be blended at any stage with petroleum diesel to develop a biodiesel mix. It can be made use of in compressionignition (diesel) engines with no major modifications.

Biodiesel is uncomplicated to use, biodegradable, nontoxic, and fundamentally no cost of sulfur and aromatics. Biodiesel can be distributed applying today's infrastructure, and its use and generation are escalating quickly. Gas stations are commencing to make biodiesel accessible to customers, and a developing number of transport fleets use it as an additive in their gasoline.

Biodiesel is attaining acceptance for the reason that it really is excellent for the setting and can be utilized in virtually any diesel motor vehicle developed in the previous 10 decades. The creation of biodiesel is an industry in its infancy in just the United States , even however the marketplace for the different fuel has been a mainstay in Europe and South The usa for years.

It is increasing swiftly all more than the earth due to expanding concerns about concentrations of environmental pollution and minimal offer of vitality resources.
In 2000, biodiesel grew to become the only substitute gas in the state to have properly completed the EPA-required Tier I and Tier II overall health outcomes testing underneath the Cleanse Air Act. These independent assessments conclusively reveal biodiesels' considerable reduction of virtually all regulated emissions, and showed biodiesel does not pose a danger to human well being.

A US Department of Vitality study showed that the output and use of biodiesel, compared to petroleum diesel, resulted in a 78.five% reduction in carbon dioxide emissions. Moreover, biodiesel has a good electricity equilibrium. For each and every unit of electricity required to produce a gallon of biodiesel, three.24 units of electricity are gained.
Many federal companies, which includes the Section of Defense (DoD), are picking to use biodiesel or biodiesel blends.

There are some downsides to biodiesel well worth mentioning. Biodiesel is generally additional costly to acquire than petroleum diesel but this differential may well diminish owing to economies of scale, the increasing cost of petroleum and govt tax subsidies. Other than increased charges, biodiesel coagulates at chilly temperatures, so cars have to be retrofitted with a fuel-heating process.

And despite the fact that biodiesel vehicles are cleaner than regular diesel in many respects, they nevertheless emit about the very same amount of money of nitrogen oxide, one of the principal components of smog. Continue to, numerous are confident that the pros of biodiesel far outweigh the down sides.
Chevron just lately gave $25 million to the University of California, Davis (UC Davis) to go on research into biofuel processing technology.

Chevron also invested in a Texas biodiesel plant, which will give them 22% possession and strengthen U.S. biodiesel production by a lot more than 50%.
South Africa-based Conventional Lender has entered the biodiesel sector with an $eight million fairness financial commitment in Biodiesel Strength Trading.
Environmentally-acutely aware celebrities these kinds of as Willie Nelson, Jack Johnson and Mandy Moore, are also supporting and investing in biodiesel. Willie Nelson even started out his have biodiesel firm, aptly titled BioWillie.

In the United States, 34 out of the 50 states are now making biodiesel fuel, with Maryland just lately included to the listing.
So how can you capitalize on the momentum of biodiesel, make a healthy return and enable to preserve the ecosystem in the approach? We have profiled just one of our beloved biodiesel plays under.
Nova Biosource Fuels (Ticker: NVAO.OB)
Nova Biosource Fuels, which was formerly Nova Vitality Holding, is an vitality organization that synthesizes and distributes renewable fuel goods. Nova's initial emphasis is to construct and operate quite a few biodiesel refineries with generation ability of more than 300 million gallons of fuel on an once-a-year foundation.

Within a few years Nova intends to construct, using proprietary patented-method technology, 7 biodiesel refineries ranging from twenty- to fifty-million gallons for each year in production potential. Nova has presently taken concrete actions toward the realization of these ambitions:
Nova concluded a personal placement in July for in excess of $18 million. These money will be employed to establish and run two to four biodiesel refineries with a production capacity of amongst one hundred twenty to 240 million gallons of biodiesel fuel for each calendar year. This news is really good as it demonstrates institutions and big buyers believe that the corporation to be a strong expense.


But the big news propelling Nova's stock value is a just lately-inked deal with ConAgra. ConAgra is 1 of North America's major packaged food items businesses. In July, Nova signed a feedstock provide and biodiesel product sales agreements with ConAgra Trade Group. The agreements present that ConAgra Trade Group will procure the vegetable oil and animal- centered feedstock specifications for the Nova-owned biodiesel refinery, as properly as promote the biodiesel gasoline and take care of the logistics for the facility.

Building on the partnership with ConAgra, Nova a short while ago signed a biodiesel profits agreement for Nova's sixty million gallon per yr biodiesel facility to be positioned in Seneca, Illinois. ConAgra Trade Team will provide advertising and outbound logistics solutions for the facility as section of the agreement.
Nova expects the Seneca refinery to be open up in the summer time of 2007.

Operational Highlights consist of the very first 10 million gallon for each year biodiesel refinery staying developed in Clinton County, Iowa nearing completion. This facility is targeted for completion in the coming months.
The 2nd refinery is becoming developed near DeForest, Wisconsin, and the facility will be wholly owned by Anamax Vitality Products and services. Nova's agreement with Anamax delivers for the structure and building of a 20 million gallon per calendar year biodiesel facility on the premises of an Anamax-owned rendering plant.

The targeted completion day of this facility is January 2007.
The third refinery is getting crafted for Scott Petroleum Corp. and the arrangement presents for the design and style and design of a twenty million gallon per calendar year biodiesel refinery found in Greenville, Mississippi. Nova by now has an arrangement with Scott Petroleum to invest in fifty p.c of this facility's generation for ten decades at roughly the production cost in trade for initial and deferred payments meant to reimburse Scott Petroleum for the incremental building prices connected with increasing the ability from ten to 20 million gallons per calendar year.

The targeted completion date for this facility is anticipated to be in early 2007.
Nova has a proprietary, patented biodiesel manufacturing technologies, formulated by Nova Biosource Fules, which is wholly-owned by Nova Energy Keeping. When you cherished this informative article and you would like to receive guidance relating to nova 3 mod i implore you to visit our own web site. This technologies lets Nova to cut down processing costs by up to 35% and general fuel manufacturing expenditures by as much as 20% from standard field practices.

This aggressive benefit final results in lessen manufacturing expenses, more rapidly facility permitting, and minimum environmental effect owing to the absence of air and drinking water squander streams.
Nova features seasoned management, like CEO Kenneth Bern who served as President of Texaco Saudi, Inc., involving 1981-1984, as Vice Chairman and Taking care of Director of Texaco Nigeria Constrained from 1984 by means of 1989, and as President of Texaco Brazil from 1989 by means of 1994.

COO Jody Powers was the previous president of Halliburton Vitality Expert services, in which he labored for 35 decades. Nova has also stacked their board with business industry experts and expert veterans in the vitality industry. Their steering and their contacts should allow Nova to take benefit of alternatives moving ahead.

Softer oil prices cut down fascination in option resources of vitality -- and their stocks. Nova's stock value experienced together with the recent decline in crude oil price ranges, but has considering the fact that been rebounded strongly. Soon after diving underneath $three.00, Nova's stock has immediately shot up to $four.00, predominantly on news of the ConAgra deal.

Nova closed now up eleven% on volume of practically triple the normal. We see Nova breaking their all-time significant of $4.forty in the coming months, giving the prospective for a rapid 10% revenue. However, Nova should be seen as a long-expression perform, as current refinery building and board appointments has shown motivation to starting to be a major biodiesel producer.

Please observe that continuing weak point in oil selling prices will suppress any value innovations for Nova. We are of the impression that oil costs are headed again previously mentioned $70 by calendar year finish and consider this will enable propel Nova's share price to all-time highs. If you disagree and feel oil will carry on down, alternate electrical power companies are not a prudent financial commitment for you.

As normally, you should really do your have thanks diligence, in particular with bulletin board stocks that have a larger danger profile.
Disclaimer: The creator does not presently very own any stock in Nova Biosource Fuels and was not compensated in any way to publish this write-up.

Retrieved from "https://en.formulasearchengine.com/index.php?title=William_Rowan_Hamilton&oldid=221659"