POV date April 2011 A vacuum sewer system uses the differential pressure between atmospheric pressure and a partial vacuum maintained in the piping network and vacuum station collection vessel. This differential pressure allows a central vacuum station to collect the wastewater of several thousand individual homes, depending on terrain and the local situation. Vacuum sewers take advantage of available .... Vacuum sewers were first installed in Europe in 1882 but until the last 30 years it had been relegated to a niche market. The first who has applied the negative pressure drainage so called vacuum sewerage ..., trains and airplanes for a long time. Technical implementations of vacuum sewerage systems were ... Collection chambers and vacuum valve units Monitoring system for collection chambers and vacuum valve units Vacuum sewer lines Central vacuum station Vacuum technology is based on differential air pressure. Rotary vane vacuum pumps generate an operation pressure of 0.4 to 0.6 bar at the vacuum station, which is also the only element of the vacuum sewerage system that must be supplied with electricity ... is needed to open or close the valve. The according energy is provided by the vacuum itself. While the valve is open, the resulting differential pressure between atmosphere and vacuum becomes the driving force and transports the wastewater towards the vacuum station. Besides these collection .... Vacuum sewer systems are considered to be free of ex and infiltration which allows the usage even in water protection areas. For this reason, vacuum sewer lines may even be laid in the same trench ... reliable transport, the vacuum sewer line is laid in a saw tooth length profile, which will be referred to more precisely afterwards. The whole vacuum sewers are filled with air at a pressure of 0.4 ... according to the pressure in the system. Considering that the vacuum idea relies on external energy .... Once arrived in the vacuum collection tank at the vacuum station, the wastewater is pumped ... more details
Multiple issues orphan February 2009 advert January 2009 primarysources April 2009 Vacuum massage is a type of therapeutic massage which is used for body sculpting, cellulite reduction and to treat such diseases as osteochondrosis , colds, bronchitis and pneumonia . The medical effect of this massage is realized by means of vacuum that causes the local rush of blood and lymph to skin from deep lying tissues, which exerts the reflex influence on vessels of internal organs. Usually vacuum massage is performed by using rubber glass, a small silicone massager. Citation needed date June 2008 Vacuum massage is believed to be one of the most trusted and efficient treatment against cellulite. Citation needed date June 2008 It smooths hypodermic fat layer and skin becomes more elastic. Vacuum massage technique The massage is easy to perform. There are three simple rules the massaged area must be greased well never use rubber glass on dry skin , use three massage movements straight line, circular and zigzag repeat each 5 6 times , control the vacuum massage doesn t have to be painful. Massage each area at least for 5 minutes. Vacuum massage benefits Effective against cellulite Easy to perform Doesn t require much time and special preparation Inexpensive Multifunctional Category Massage therapy ... more details
?pageID 1 ref Vacuum packing reduces atmospheric oxygen, limiting the growth of aerobic bacteria ... term basis, vacuum packing can also be used to store fresh foods, such as vegetables, meats, and liquids, because they inhibit bacterial growth. Vacuum packing greatly reduces the bulk of non food items. For example, clothing and bedding can be stored in bags evacuated with a domestic vacuum cleaner or a dedicated vacuum sealer. This technique is sometimes used to compact household waste , for example where a charge is made for each full bag collected. Vacuum packaging products using plastic bag s, can isters, bottle s, or mason jar s are available for home use. Vacuum packaging delicate food ... and delicate foods such as potato chips. External sealers External vacuum sealers involve a bag being attached to the vacuum sealing machine externally. The machine will remove the air and seal the bag, which is all done outside the machine. Chamber sealers Image Tabletop Vacuum Packaging Machine.png thumb right 150px Tabletop Vacuum Packaging Machine Chamber sealers require the entire product ... burn also ruins the flavor and texture of foods. Vacuum packing reduces freezer burn by preventing the food from exposure to the cold, dry air. Sous vide cooking Vacuum packaging also allows for a special cooking method, sous vide . Sous vide, French language French for under vacuum , involves poaching food that is vacuum sealed in a plastic bag. Food safety In an oxygen poor environment, Anaerobic organism s can proliferate, potentially causing food safety problems. Vacuum packing is often ... 6 packaging food preservation Category Food preservation Category Vacuum Category Packaging fr Sac sous ... more details
In quantum field theory , and specifically quantum electrodynamics , vacuum polarization describes a process in which a background electromagnetic field produces virtual particle virtual electron &ndash positron pairs that change the distribution of charges and currents that generated the original electromagnetic field. It is also sometimes referred to as the self energy of the gauge boson photon . The effects of vacuum polarization were observed experimentally in 1997 using the TRISTAN particle accelerator in Japan. ref cite journal last Levine first I. coauthors TOPAZ Collaboration title Measurement of the Electromagnetic Coupling at Large Momentum Transfer journal Physical Review Letters year 1997 volume 78 pages 424 427 doi 10.1103 PhysRevLett.78.424 bibcode 1997PhRvL..78..424L issue 3 ref Explanation According to quantum field theory , the ground state of a system with interacting particles is not simply empty space. Rather, it contains short lived virtual particle virtual particle&ndash antiparticle pairs which are created out of the vacuum and then annihilate each other. Some of these particle&ndash ... will be weaker than would be expected if the vacuum were completely empty. This reorientation of the short lived particle antiparticle pairs is referred to as vacuum polarization . The one loop contribution of a fermion&ndash antifermion pair to the vacuum polarization is represented by the following diagram Image Vacuum polarization.svg Vacuum polarization tensor The vacuum polarization is quantified by the vacuum polarization tensor sup sup p which describes the dielectric effect as a function of the four momentum p carried by the photon. Thus the vacuum polarization depends on the momentum ... sup p is fixed by the Ward identity . Note Vacuum polarization affecting spin interactions has also ... Further reading For a derivation of the vacuum polarization in QED, see section 7.5 of M.E. Peskin and D.V. ... QED vacuum QCD vacuum Virtual particles QED Category Quantum field theory Category Quantum electrodynamics ... more details
refimprove date September 2009 In physics, the vacuum level refers to the energy of a free stationary electron that is outside of any material it is in a perfect vacuum . It may be taken as infinitely far away from a solid or modified to be defined near a surface. ref http mat.chem.nagoya u.ac.jp info newpublicationlist 1999 290.pdf By Hisao Ishii, Kiyoshi Sugiyama, Eisuke Ito, and Kazuhiko Seki Energy Level Alignment and Interfacial Electronic Structures at Organic Metal and Organic Organic Interfaces Adv. Mater. 1999, 11, No. 8 ref Its definition and measurement are often discussed in UPS literature, for example ref http www.princeton.edu kahnlab publications AdvMat15 271.pdf Cahen and Kahn Adv. Mater. 2003, 15, no 4 Feb 17 ref As the vacuum level is a property of the electron and free space , it is often used as the level of alignment for the energy level s of two different materials. The vacuum level alignment approach may or may not hold due to details of the interface. It is particularly important in the design of vacuum device components such as cathodes. The phrase vacuum level also occurs often in texts on squeezed light where it refers to an unsqueezed measurement. For example, Thus, when the noise level in the spectrum analyzer shows broadband squeezing below the vacuum level, it also indicates the presence of entanglement between upper and lower sidebands. ref http www users.cs.york.ac.uk schmuel papers ybf07.pdf Hidehiro Yonezawa,1,2 Samuel L. Braunstein,3 and Akira Furusawa1,2 Experimental Demonstration of Quantum Teleportation of Broadband Squeezing PRL 99, 110503 2007 ref Note that the phrase vacuum level may also refer to a measurement of residual pressure in a vacuum system or a device that uses differential pressure such as a carburetor but this usage should be very clear from context. References references Category Quantum chemistry de Vakuumniveau fr Niveau du vide ja ... more details
A vacuum solution is a solution of a field equation in which the sources of the field are taken to be identically zero. That is, such field equations are written without matter interaction i.e. set to zero . Examples In Maxwell s theory of electromagnetism , a vacuum solution would represent the electromagnetic field in a region of space where there are no electromagnetic sources charges and electric currents , i.e. where the current 4 vector vanishes ref name Esposito1997 Citation doi 10.1016 S0375 9601 96 00872 9 title Classical vgr? c solutions of Maxwell s equations and the photon tunneling effect url http linkinghub.elsevier.com retrieve pii S0375960196008729 year 1997 author Esposito, S. journal Physics Letters A pages 203 209 volume 225 issue 4 6 accessdate 2009 07 04 arxiv physics 9611018 bibcode 1997PhLA..225..203E ref math J a 0 math Einstein s theory of general relativity where a vacuum solution general relativity vacuum solution ref name Stephani2003 Citation title Exact solutions of Einstein s field equations url http www.loc.gov catdir samples cam033 2002071495.pdf year 2003 author Stephani, H. accessdate 2009 07 04 ref would represent the gravitational field in a region of spacetime where there are no gravitational sources masses , i.e. where the energy momentum tensor ... Relativity Static and Stationary Vacuum Solutions url http www3.interscience.wiley.com journal ... Kaluza Klein vacuum static field equations ref name Sorkin1983 Citation title Kaluza klein monopole ... 90 volume 51 issue 2 bibcode 1983PhRvL..51...87S ref Kasner vacuum solution ref Citation title Where ... ref See also Maxwell s equations In vacuum Kerr vacuum Einstein field equations Ernst vacuum Kasner metric Vacuum solution general relativity References Citation title Gravitational lensing effects of vacuum strings Exact solutions bibcode 1985ApJ...288..422G year 1985 journal Astrophysical ... doi 10.1007 s002200050571 title The initial boundary value problem for Einstein s vacuum field ... more details
Unreferenced date May 2009 Infobox musical artist See Wikipedia WikiProject Musicians name Vacuum image Vacuum 2002 Lindblom, Wollbeck .jpg caption Anders Wollbeck and Mattias Lindblom of Vacuum image size background group or band alias origin Sweden genre Pop music Pop , Electronic music electronic years active 1996&ndash present label associated acts website http myspace.com vacuumpeople http blog.myspace.com vacuumpeople current members Mattias Lindblom br Anders Wollbeck past members Marina Schiptjenko br Alexander Bard Vacuum is the name of a Swedish people Swedish pop band . The members are Mattias Lindblom and Anders Wollbeck . They also work as song writer s and Producer music producers under the same name. As songwriters and producers Wollbeck Lindblom have worked with artists such as Tarja Turunen , Garou singer Garou , Monrose , Keisha Buchanan , F x band f x and The Canadian Tenors . Wollbeck Lindblom are signed to Universal Music Publishing world wide. History Vacuum the band ... of the group. After the second album Bard left the group. Vacuum then released the single Starting ..., in 2004 , Vacuum s critically acclaimed album Your Whole Life Is Leading Up To This , marking a new ... artists as well. Vacuum then released the singles Six Billion Voices in 2006 and Walk On The Sun ... single written in collaboration with Zlanabitnig. Vacuum is currently working on new material. The band enjoys a huge fan following. June 4, 2011 Vacuum released the song Black Angels. Discography ... Lindblom Anders Wollbeck External links http myspace.com vacuumpeople Official Vacuum page at MySpace http vacuum music.com A fan site http community.livejournal.com vacuum music Vacuum Community LJ http soundcloud.com vacuum official Vacuum on SoundCloud http illuminatiarts.tumblr.com Blog DEFAULTSORT Vacuum Category Swedish musical groups Category Synthpop groups Sweden band stub de Vacuum el Vacuum ru Vacuum fi Vacuum sv Vacuum uk Vacuum ... more details
of a vacuum pump A vacuum pump is a device that removes gas molecules from a sealed volume in order to leave behind a partial vacuum . The first vacuum pump was invented in 1650 by Otto von Guericke ... title Vacuum and Vacuum Technology edition Second year 1991 publisher VCH Publishers Inc. pages 1330 ... a rough vacuum in the vessel being evacuated before the momentum transfer pump can be used to obtain the high vacuum, as momentum transfer pumps cannot start pumping at atmospheric pressures. Second the positive displacement pump backs up the momentum transfer pump by evacuating to low vacuum the accumulation of displaced molecules in the high vacuum pump. Entrapment pumps can be added to reach ... refers to the volume leak rate multiplied by the pressure at the vacuum side of the leak, so ... is linked from Vacuum Image L Pumpe2.png thumb The manual water pump draws water up from a well by creating a vacuum that water rushes in to fill. In a sense, it acts to evacuate the well, although the high leakage rate of dirt prevents a high quality vacuum from being maintained for any length ... be pulled, so it is technically impossible to create a vacuum by suction. Suction is the movement of fluids into a vacuum under the effect of a higher external pressure, but the vacuum has to be created first. The easiest way to create an artificial vacuum is to expand the volume of a container. For example ... of the lungs to increase. This expansion reduces the pressure and creates a partial vacuum, which is soon ... without requiring infinite growth, a compartment of the vacuum can be repeatedly closed off, exhausted ... vacuum. Because of the pressure differential, some fluid from the chamber or the well, in our example ... achieve 0.1 Pa. A positive displacement vacuum pump moves the same volume of gas with each cycle, so ... is linked from Vacuum Image Cut through turbomolecular pump.jpg thumb A cutaway view of a turbomolecular high vacuum pump In a momentum transfer pump, gas molecules are accelerated from the vacuum ... more details
Expert subject Physics date November 2010 Vacuum energy is an underlying background energy that exists in space even when the space is devoid of matter free space . The concept of vacuum energy has been ... principle . The effects of vacuum energy can be experimentally observed in various phenomena ... , the vacuum energy in a cubic meter of free space has been estimated to be 10 sup 9 sup Joule s. ref ... 113 sup Joules per cubic meter. ref Peter G. Millonni The Quantum Vacuum ref ref de la Pena and Cetto ... to the theory, even the vacuum has a vastly complex structure and all calculations of quantum field theory must be made in relation to this model of the vacuum. The theory considers vacuum to implicitly ... cancel out on average leaving the vacuum empty in the literal sense of the word. One important exception, however, is the vacuum energy or the vacuum expectation value of the energy. The quantization ... . In all practical calculations, this is how the infinity is handled. Vacuum energy can also be thought of in terms of virtual particles also known as vacuum fluctuations which are created and destroyed out of the vacuum. These particles are always created out of the vacuum in particle antiparticle ... diagrams . Note that this method of computing vacuum energy is mathematically equivalent to having .... Additional contributions to the vacuum energy come from spontaneous symmetry breaking in quantum field theory . Implications Vacuum energy has a number of consequences. In 1948, Netherlands Dutch ... attractive force between closely placed metal plates due to resonance s in the vacuum energy in the space ... verified. It is therefore believed that the vacuum energy is real in the same sense that more ... effect is no certain proof for vacuum energy since it can also be explained without this theory. ref R. L. Jaffe The Casimir Effect and the Quantum Vacuum . In Physical Review D . Band 72, 2005 http arxiv.org abs hep th 0503158 ref Other predictions are harder to verify. Vacuum fluctuations are always ... more details
A vacuum furnace is a type of furnace that can heat materials, typically metals, to very high temperatures and carry out processes such as brazing , sintering and heat treatment with high consistency and low contamination. In a vacuum furnace the product in the furnace is surrounded by a vacuum . The absence of air or other gases prevents heat transfer with the product through convection and removes a source of contamination. Some of the benefits of a vacuum furnace are Uniform temperatures in the range 1100 1500 Celsius C 2000 2800 Fahrenheit F Temperature can be controlled within a small area Low contamination of the product by carbon, oxygen and other gases Quick cooling quenching of product. The process can be computer controlled to ensure metallurgical repeatability. Heating metals to high temperatures normally causes rapid oxidation , which is undesirable. A vacuum furnace removes the oxygen and prevents this from happening. An inert gas , such as Argon , is typically used to quickly cool the treated metal back to non metallurgical levels below 400 F after the desired process in the furnace. ref cite web url http www.imp.mtu.edu metallic vacuum furnace.html title Vacuum Furnace at IMP ref This inert gas can be pressurized to two times atmosphere or more, then circulated through the hot zone area to pick up heat before passing through a heat exchanger to remove heat. This process is repeated until the desired temperature is reached. Common uses A common use of a vacuum furnace is for the heat treatment of steel alloys. Many general heat treating applications involve the hardening and tempering of a steel part to make it strong and tough through service. Hardening involves heating the steel to a pre determined temperature, then cooling it rapidly. Vacuum furnaces are ideal ... for vacuum furnaces is Vacuum Carburizing, also known as Low Pressure Carburizing or LPC. In this process ... Category Industrial furnaces Category Vacuum systems Furnace tr Et v ... more details
the mould by applying vacuum between the mould surface and the sheet. The vacuum forming process can ... manufacturer of vacuum formed plastics was http www.robinsonind.com Robinson Industries of Coleman ... of 3 . Otherwise, release of the formed plastic and the mold will most likely be difficult. Vacuum ... surface and before vacuum is applied. ref J.L. Throne, Understanding Thermoforming , Hanser Gardner Publications, Inc., Cincinnati, OH, 1999 ref Suitable materials for use in vacuum forming are conventionally ... form to almost any shape. Vacuum forming is also appropriate for transparent materials such as acrylic ... for military fixed wing aircraft and bubbles for rotary wing aircraft. Typical heavy gauge vacuum forming applications Original equipment manufacturers OEM s utilize heavy gauge vacuum formed components for production quantities in the range of 250 3000 annual production volume. Vacuum formed components ... cab Railcar interior trim and seat components Common problems encountered with vacuum forming ... of Vacuum Forming Moulds File Thermoformingtool.jpg thumb Vacuum forming tool Wood Pattern s wood patterns are generally the first stage to a vacuum forming project. They are relatively inexpensive ... also Vac u form a toy from the 1960s based on vacuum forming References references Further reading D.E. Walsh, Do It Yourself Vacuum Forming for the Hobbyist , Workshop Publishing, Lake Orion, MI, 2002 ... support.knowlton.ohio state.edu files FormechVacuumGuide.pdf A Vacuum Forming Guide http plastics.turkavkaz.ru processes thermoforming vacuum forming Vacuum Forming Process Description DEFAULTSORT Vacuum Forming Category Plastics applications Category Packaging de Vakuumformen fr Moulage sous vide ... more details
Technical date April 2011 In quantum field theory , a false vacuum is a metastability metastable sector of space that appears to be a vacuum state perturbative vacuum , but is unstable due to instanton ... fluctuations or the creation of high energy particles. Simply put, the false vacuum is a maxima ... Falsevacuum.svg thumb 240px A scalar field in a false vacuum. Note that the energy E is higher than that in the true vacuum or ground state , but there is a barrier preventing the field from classically rolling down to the true vacuum. Therefore, the transition to the true vacuum must be stimulated ... mechanical tunneling . Vacuum metastability event This section is linked from Ultimate fate of the universe ... that we are living in a false vacuum has never been a cheering one to contemplate. Vacuum decay is the ultimate ecological catastrophe in the new vacuum there are new constants of nature after vacuum decay, not only is life as we know it impossible, so is chemistry as we know it. However, one could always draw stoic comfort from the possibility that perhaps in the course of time the new vacuum ... that we are living in a false vacuum is only a possibility, and Chaotic Inflation theory suggests that the universe may be in either a false vacuum or a true vacuum state. If a bubble of lower energy vacuum were nucleated, it would expand, approaching at nearly the speed of light and destroying the Earth instantaneously, without any forewarning. ref name colemandeluccia Thus, this vacuum metastability ... A. Landis , ref name landis cite journal author Geoffrey A. Landis title Vacuum States journal ... density sufficiently high to penetrate the barrier and stimulate the decay of the false vacuum to the lower energy vacuum. Hut and Rees, ref name hutrees cite journal author P. Hut, M.J. Rees title How stable is our vacuum? journal Nature year 1983 pages 508 509 issue 5908 volume 302 doi 10.1038 302508a0 ... vacuum. Particle accelerations have reached energies of only approximately seven Tera tera electron ... more details
Image 2008 05 05 1990 Geo Storm GSi vacuum servo.jpg thumb right Brake booster from a Geo Storm . Image Servofreno seccionado.jpg thumb right Brake vacuum servo section A vacuum servo is a component used on motor vehicle s in their brake braking system, to provide assistance to the driver by decreasing the braking effort. In the USA it is commonly called a brake booster. Background It is used on virtually all vehicles which use hydraulic brake s for their primary braking circuit. Vacuum servos are not used on vehicles which use cables, rods or other mechanical linkages , or pressurized air systems for their primary brake circuits. It uses a stored vacuum to increase braking force applied by the driver to the brake pedal, before applying the transferred force to the brake master cylinder . The vacuum is generated in two distinct methods, dependent on the type of internal combustion engine , or other motive force as in electric vehicle s . In petrol engine s, the manifold vacuum is utilized, whereas in diesel engine s, a separate vacuum pump is used. The vacuum is transferred to the servo along semi rigid plastic lines, and is stored in the servo by using a check valve non return valve . The vacuum booster or vacuum servo is used in most modern hydraulic brake systems which contain four wheels. The vacuum booster is attached between the master cylinder and the brake pedal and assists the braking force applied by the driver. These units consist of a hollow housing with a movable rubber diaphragm across the center, creating two chambers. When attached to the low pressure portion of the throttle body or intake manifold of the engine, the pressure in both chambers of the unit is lowered ... conservative 50 manifold vacuum, an assisting force of about 1500 N 150 kgf is produced by a 20cm ... on the brake pedal through a brake booster pushrod. The brake booster usually uses vacuum from ... vacuum pump to enable it. Without the engine running the brake pedal feels very hard and ineffective ... more details
Image Vacuum distillation of DMSO at 70C.jpg thumb At atmospheric pressure, dimethyl sulfoxide boils at 189 C. Under a vacuum, it distills off into the connected receiver at only 70 C. Vacuum distillation .... Vacuum distillation is used with or without heating the mixture. Laboratory scale applications Laboratory scale vacuum distillation is used when liquids to be distilled have high atmospheric boiling ..., Boulder CU Boulder Organic Chemistry Teaching Labs ref ref http www.epa.gov esd chemistry vacuum default.htm Vacuum Distillation New Method for Analyzing Organic Chemicals in a Wide Array of Samples ... What is vacuum distillation? Argonne National Laboratory s NEWTON Ask A Scientist ref Temperature sensitive materials such as beta carotene also require vacuum distillation to remove solvent s from the mixture without damaging the product. Another reason vacuum distillation is used is that compared ... applications where heat transfer is produced using heat exchanger s. Vacuum distillation is sometimes referred to as low temperature distillation. There are many laboratory applications for vacuum ... examined for scratches and cracks which could result in implosions when the vacuum is applied ... of the University of British Columbia ref is a type of vacuum distillation apparatus used ... immersing it in a heated bath of water or oil. Typically, the vacuum in such systems is generated by a water aspirator or a vacuum pump of some type. Distillation of high boiling and or air .... A simple laboratory vacuum distillation glassware set up can be used, in which the vacuum can be replaced ... the vacuum or the heat source, and thus can remain in a state of Reflux distillation reflux . To do this, the distillate receiver vessel is first isolated from the vacuum by means of the Teflon valves. The vacuum over the sample is then replaced with an inert gas such as nitrogen or argon and the distillate receiver can then be stoppered and removed from the system. Vacuum distillation set up using ... more details
Distinguish Vacuum manifold Manifold vacuum , or engine vacuum in an internal combustion engine is the difference ... . Manifold vacuum is an effect of a piston s movement on the Stroke engine Induction stroke induction ... in the engine. In some engines, the manifold vacuum is also used as an Automobile ancillary power auxiliary power source to drive engine accessories. Manifold vacuum should not be confused with venturi effect venturi vacuum , which is an effect that is exploited in carburetor s to achieve a fixed ... vacuum is present in all naturally aspirated engine s that use throttles including carburetor ... , ambient air is free to fill the intake manifold, increasing the pressure filling the vacuum ... a MAP sensor which measures the manifold absolute pressure to control fuel flow. Manifold vacuum vs. venturi vacuum Manifold vacuum is caused by a different effect than venturi vacuum , which is present inside carburetor s. Venturi vacuum is caused by the venturi effect and depends on the total mass flow through the carburetor. In engines that use carburetors, venturi vacuum is proportional to the total mass flow through the engine and hence the total power output . Manifold vacuum may also be ported ... vacuum. Ported vacuum is often used for distributors and emissions items. Manifold vacuum in cars ... under light or no load and low throttle, there is high manifold vacuum. As the throttle is opened ... vacuum will be created. Engine speed is low but the butterfly valve is fully open. Since the pistons ... ambient pressure. More vacuum is created in some situations. On deceleration or when descending ... a strong vacuum on the engine side of the butterfly valve which will tend to limit the speed ... trucks see Jake brake . Uses of manifold vacuum File 1929 AEC Regal UU6646.jpg thumb Autovac fuel ... maximum momentary fuel efficiency by adjusting driving habits minimizing manifold vacuum increases momentary efficiency. A weak manifold vacuum under closed throttle conditions shows that the butterfly ... more details
Orphan date November 2010 Vacuum metallizing is a process where a metallic coating material is placed in a vacuum chamber with the workpiece to be coated. The material that is being applied is then heated until it starts to evaporate this vaporized metal condenses on the product or workpiece as a thin metallic film. As this is happening, the part is being rotated for uniformity of the coat. Thin layers of paint can then be applied to produce other colors. Once complete, a clear sealer is usually added to prevent flaking. Process characteristics Done within a vacuum Vaporizes the metal Can be used on glass , plastic , metal, ceramic , and paper materials Pieces being coated must be extremely clean It produces a very thin coat of metal Target materials Thickness ranges for 0.01 to 0.2 micrometres. When coating a piece it changes its conductivity, it improves its corrosion resistance, and it enhances its appearance. Some target metals are aluminum, copper, platinum, titanium, chromium titanium, gold, lead, nickel, silver, tin and tantalum. How it works The piece to be coated is placed inside the vacuum chamber on a rotating rack. A vacuum is created in the chamber and the metallizing material is then heated until it evaporates. The vaporized metal bonds to the piece, making a thin coating on the piece. Bibliography Robert H. Todd, Dell K. Allen, and Leo Alting 1994 . Manufacturing Processes Reference Guide First Edition . New York Industrial Press Inc. Category Industrial processes Category Coatings Category Metal plating ... more details
A vacuum arc can arise when the surfaces of metal electrode s in contact with a good vacuum begin to emit electron s either through heating thermionic emission or via an electric field that is sufficient to cause field electron emission . Once initiated, a vacuum arc can persist since the freed particles gain kinetic energy from the electric field, heating the metal surfaces through high speed particle collisions. This process can create an incandescent cathode spot which frees more particles, thereby sustaining the arc. At sufficiently high currents an incandescent anode spot may also be formed. Electrical discharge in vacuum is important for certain types of vacuum tube s and for high voltage vacuum switch es. The thermionic vacuum arc TVA is a new type of plasma source, which generates a pure metal and ceramic vapour plasma containing ions with a directed energy. TVA discharges can be ignited in high vacuum conditions between a heated cathode electron gun and an anode tungsten crucible containing the material. The accelerated electron beam, incident on the anode, heats the crucible, together with its contents, to a high temperature. After establishing a steadystate density of the evaporating anode material atoms, and when the voltage applied is high enough, a bright discharge is ignited between the electrodes. References cite book last Messyats first Gennady A. coauthors Proskurovsky, D. I. title Pulsed Electrical Discharge in Vacuum Springer Series on Atoms and Plasmas, 5 url edition 1st year 1989 publisher Springer Verlag location isbn 0 387 50725 6 cite book last Greenwood first Allan coauthors title Vacuum Switchgear I E E Power Engineering Series url edition 1st year 1994 publisher Pergamon Press location isbn 0 85296 855 8 cite journal last Akan first Tamer coauthors Demirkol, Serdar Ekem, Naci Pat, Suat Musa, Geavit title Study of Metal and Ceramic Thermionic Vacuum arc Discharges year 2007 journal Plasma Sci. Technol. volume 9 pages 280 283 doi 10.1088 1009 ... more details
Refimprove date July 2007 Vacuum evaporation is the process of causing the pressure in a liquid filled container to be reduced below the vapor pressure of the liquid, causing the liquid to evaporate at a lower temperature than normal. Although the process can be applied to any type of liquid at any vapor pressure, it is generally used to describe the boiling of water by lowering the container s internal pressure below standard atmospheric pressure and causing the water to boil at room temperature . When the process is applied to food and the water is evaporate d and removed, the food can be stored for long periods of time without spoiling. It is also used when boiling a substance at normal temperatures would chemically change the consistency of the product, such as egg whites coagulating when attempting to dehydrate the albumen into a powder. This process was invented by Henri Nestl in 1866, of Nestl Chocolate fame, Citation needed date July 2007 although the Shakers were already using a vacuum pan earlier than that see condensed milk . This process is used industrially to make such food products as evaporated milk for milk chocolate , and tomato paste for ketchup . File 00 vacuum pan sugar factory.JPG thumb right vacuum pans in a beet sugar factory In the sugar industry the vacuum evaporation is used in the crystallization of sucrose solutions. Traditionally, this process was performed in batch mode, but nowadays also continuous vacuum pans are available ref http www.bma worldwide.com products sugar and sweeteners vacuum pans batch and continuous types vkt.html article on continuous vacuum pans, retrieved on 21 September, 2011 ref Vacuum evaporation is also a form of physical ... of pumping a vacuum chamber to pressures of less than math 10 5 math torr and heating a material ... references See also Freeze drying Ultrasonic spray deposition Vacuum deposition Category Evaporators Category Food preservation Category Food science Category Vacuum tech stub es Evaporaci n ... more details
Vacuum cementing or vacuum welding is the natural process of solidifying small objects in a hard vacuum . The most notable example is Lunar dust dust on the surface of the Moon . This effect was reported to be a problem with the first American and Soviet satellites, as small moving parts would seize together. citation needed date October 2010 However, in 2006, Henry Spencer stated that the phenomenon of spontaneous cold welding in outer space is basically a myth , pointing out that there are no documented cases of it actually occurring in orbit, except in experiments deliberately designed to provoke it with susceptible materials, great care to avoid contamination, and deliberate mechanical removal of oxide layers, etc. . ref cite web author Henry Spencer View profile More options url http groups.google.com group sci.space.history msg 9f09b7136c1206f5 title Plans for Sputnik 50th Anniversary? sci.space.history & 124 Google Groups publisher Groups.google.com date 2006 10 02 accessdate 2010 11 01 ref Three years following this 2006 post the European Space Agency published a peer review ed scholarly paper paper detailing why cold welding is a significant issue that spacecraft designers need to carefully consider. The conclusions of this appropriately titled study can ... and Fretting under Vacuum . The paper also cites a documented example from 1991 with the Galileo spacecraft ... of difficulty is that vacuum aka cold welding does not exclude relative motion between the surfaces ... of both vacuum welding and galling and or fretting and or impact . Galling and vacuum welding ... vacuum welding http ntrs.nasa.gov archive nasa casi.ntrs.nasa.gov 19900014421 1990014421.pdf Lunar Rated Fasteners Page 3 specifies how to build components resistant to vacuum welding references See also Cold welding Passivation Corrosion in space DEFAULTSORT Vacuum Cementing Category Spaceflight Category Vacuum crater stub ... more details
refimprove date August 2009 File Vacuum tanker for pit emptying.jpg thumb Vacuum truck. A vacuum truck is a tank truck with a heavy duty vacuum designed to pneumatically load solids, liquids, sludge or slurry through suction lines typically 2 4 in diameter with 3 being the norm. The typical pump used in the industry is the rotary vane pump rotary vane vacuum pump . The truck can be configured to be a direct PTO belt or a PTO hydraulic drive system. There are two different ways to mount the pump either directly on the truck with PTO drive or on the trailer with a pony motor. Each application has different handling characteristics. The trucks are often used by towns and municipalities for street cleanup, sewerage sewers , individual septic system s ref Lloyd Kahn, John Hulls, Peter Aschwanden, The Septic System Owner s Manual Shelter Publications, Inc., 2007 ISBN 0936070404 page 49 ref and can also be used for cleanup of Soil contamination contaminated soil . The trucks are mostly used in the petroleum industry , for cleaning of storage tanks and spills. They are also a important part of drilling oil and natural gas oil well wells , as they are located at the drilling site. Vacuum trucks are used to remove drilling mud, drilling cuttings, cement, spills, and for removal of brine water from production tanks. They dispose of this in sump pit s, treatment plants or if within safe levels may be spread out in a farmer s field. ref Cite news url http thechronicleherald.ca NovaScotia 1135125.html publisher Chronicle Herald title Soil tests show no risk date July 31, 2009 ref References references DEFAULTSORT Vacuum Truck Category Industrial equipment Category Cleaning tools Truck stub de Saugwagen fr Hydrocureuse ... more details
refimprove date September 2010 The vacuum brake is a brake braking system employed on train s and introduced in the mid 1860s. A variant, the automatic vacuum brake system, became almost universal in British train equipment and in countries influenced by British practice. Vacuum brakes also enjoyed a brief ... in the United Kingdom from the 1970s onward. The vacuum brake system is now obsolete it is not in large ... train. A major advance was the adoption of a vacuum braking system, in which flexible pipes were ... the locomotive. The earliest scheme was a simple vacuum brake, in which vacuum was created by operation of a valve on the locomotive the vacuum actuated brake pistons on each vehicle, and the degree of braking could be increased or decreased by the driver. Vacuum, rather than compressed air, was preferred because steam locomotives can be fitted with ejector s venturi devices that create vacuum without moving parts. The simple vacuum system had the major defect that in the event of one of the hoses ... coupling of the hoses, or otherwise the vacuum brake on the entire train was useless. The automatic vacuum brake had been developed it was designed to apply fully if the train becomes divided or if a hose ... harv ref The train was fitted with the simple vacuum brake, which was useless on the disconnected portion ... trains. How the automatic vacuum brake works File Vacuum brake cylinder off.png thumb Vacuum brake cylinder in running position the vacuum is the same above and below the piston File Vacuum brake cylinder ... is forced up In its simplest form, the automatic vacuum brake consists of a continuous pipe the train pipe running throughout the length of the train. In normal running a partial vacuum is maintained ... pressure acts against pistons in cylinders in each vehicle. A vacuum is sustained on the other face ... running the length of each vehicle, with flexible vacuum hoses at each end of the vehicles, and coupled ... an ejector on the locomotive, to create vacuum in the train pipe controls for the driver to bring ... more details
A power vacuum is, in its broadest sense, an expression for a condition that exists when someone has lost control of something and no one has replaced them. ref http dictionary.cambridge.org dictionary british power vacuum ref It is usually used to refer to a politics political situation that can occur when a government has no identifiable central authority . The metaphor implies that, like a physical vacuum , other forces will tend to rush in to fill the vacuum as soon as it is created, perhaps in the form of an armed militia or Iraqi insurgency insurgents , military Coup d tat coup , warlord or dictator . Historian Fernand Braudel compared the situation of History of Italy Italy during the Renaissance as a cyclonic zone, an enormous vacuum , which would sweep in foreign armies blockquote The strength of the barriers in eastern and south western Europe varied from century to century. The nomads worlds rotated between these areas of negligence, weakness and sometimes ineffectual vigilance. A physical law drew them now westwards, now eastwards, according to whether their explosive life ... s classic work drew attention to a cyclonic zone, an enormous vacuum in 1494 over the fragmented ... a power vacuum of some sort. For example, the Somali Civil War war torn nation of Somalia is currently mired in a power vacuum, with no central Politics of Somalia government or List of Presidents ... war in Bosnia in 1992 was marked with a power vacuum following disintegration of Yugoslavia. A power vacuum can also occur following a constitutional crisis in which large portions of the government ... of power. After the World War II Second World War , there was a power vacuum in Europe. Along ... Baath party members from the Iraqi government after the invasion created a power vacuum which ... ref The general concept of a power vacuum is relevant to many personal and organizational ... backlash occurring in a power vacuum situation. References reflist Category Politics by issue ... more details
Quantum field theory cTopic Topics In quantum field theory , the vacuum state also called the vacuum .... Zero point field is sometimes used as a synonym for the vacuum state of an individual quantized field. According to present day understanding of what is called the vacuum state or the quantum vacuum ... vacuum an experimental challenge in Laser physics at the limits page 197 publisher Springer location ... 22vacuum state 22 ref and again it is a mistake to think of any physical vacuum as some absolutely ..., the vacuum state is not truly empty but instead contains fleeting electromagnetic waves and particles ... ref name Dittrich cite book author Walter Dittrich & Gies H title Probing the quantum vacuum perturbative ... Vacuum ref The QED vacuum of quantum electrodynamics or QED was the first vacuum of quantum field theory ... of the Standard Model that deals with strong interaction s, and QCD vacuum is the vacuum of quantum ... Ion Collider , and is related to the so called vacuum structure of strong interactions . ref name ... 0521385369 year 2002 publisher Cambridge University Press ref Non vanishing vacuum state If the quantum field theory can be accurately described through perturbation theory , then the properties of the vacuum ... or more accurately, the ground state of a QM problem . In this case the vacuum expectation value ... theory of superconductivity field operators may have non vanishing vacuum expectation value s called condensate quantum field theory condensate s. In the Standard Model , the non zero vacuum ... by which the other fields in the theory acquire mass. The energy of the vacuum state main Vacuum energy In many situations, the vacuum state can be defined to have zero energy, although the actual situation is considerably more subtle. The vacuum state is associated with a zero point energy , and this zero ... . In physical cosmology , the energy of the cosmological vacuum appears as the cosmological constant ... vacuum state must explain the physically observed cosmological constant. The symmetry of the vacuum ... more details
are free and the mattress can be moulded. Usually, the vacuum mattress is put on a stretcher ... are then tied to secure the patient. A sheet is usually put on the vacuum mattress, for three reasons ... casualty, to help the patient transfer at the emergency room . Use of the vacuum mattress The full spine immobilisation splint medicine splint is performed with a rigid cervical collar a vacuum ... . Preparation of the vacuum mattress Image Vacuum mattress preparation.png thumb preparation of the vacuum mattress The vacuum mattress is put on a stretcher or possibly on a long spine board . The straps ... that the pump manual or electrical works in the right direction. Moulding the mattress Image Vacuum mattress moulding.png thumb moulding of the vacuum mattress There are three ways to put the casualty on the vacuum mattress Casualty lifting Vertical lift lifting the casualty and pushing the stretcher ..., the vacuum valve is up and at the feet of the casualty. Once the casualty is on the mattress, the sheet ... procedure can be used the vacuum mattress is put besides the casualty, on a protecting ground ... The vacuum mattress is an alternative to the use of a long spine board . Its advantages .... Its drawbacks are it is relatively fragile, and becomes useless if only partially inflated the vacuum requires a perfectly sealed envelope See also Vacuum splint External links http www.neann.com ... more details
Novel article template owned by Wikipedia WikiProject Novels Infobox Book name Vacuum Diagrams title orig translator image Image Vacuum Diagrams Stephen Baxter.jpg center 200px author Stephen Baxter cover artist country Great Britain language English language English series Xeelee Sequence genre Science fiction publisher Voyager Books Voyager UK release date 24 April 1997 media type Print Paperback pages size weight isbn 0 00 225425 5 dewey 823 .914 21 congress PR6052.A849 V33 1997 oclc 37126918 preceded by Ring book Ring followed by Reality Dust Vacuum Diagrams is a collection of science fiction short stories written by Stephen Baxter . The collection connects the novels of the Xeelee Sequence and also shows the history of mankind in the Xeelee universe, and ultimately the universe. While each short story in the collection is self contained, the stories are presented as being contained in the context of the first story, Eve , about a man who is forced to witness the events in the short stories by a god like being. Eve acts as a structure for the short stories, with an introduction at the beginning of Vacuum Diagrams , short scenes occurring between each era with Eve character explaining and introducing the next section , and an ending that wraps up the plot for the Eve story itself. Vacuum Diagrams was nominated for the Philip K. Dick Award in 1999. ref name WWE 1999 cite web url http www.worldswithoutend.com books year index.asp?year 1999 title 1999 Award Winners & Nominees ... events from each story plotted Vacuum Diagrams contains the following stories all previously published ... 1992 Vacuum Diagrams 1990 ERA The War to End Wars Stowaway 1991 The Tyranny of Heaven 1990 Hero ... Lords 1991 Epilogue Eve Vacuum Diagrams is also the title of the fifteenth short story by Stephen ... magazine Interzone in 1990. The title Vacuum Diagrams refers to the violation and reassertion ... novel.asp?ID 481 Vacuum Diagrams at Worlds Without End Category 1997 short story collections ... more details
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