Fundamentals of Vacuum Technology (1248463), страница 68
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126F = FaradS = SiemensC = Coulombsee Table V in Sect. 9J = Joule3/5 am á sÐ2m2, cm2mÐ2 á sÐ1; cmÐ2 á sÐ1Hz, kHz, MHzcm3 (NTP)ÐÐÐÐÐÐÐÐÐÐm2 á d á barJ á kgÐ1 á KÐ1mm2 á sÐ1, cm2 á sÐ1JN, kN, mNm, cm, mmmÐÐÐÐÐÐÐÐ ; KÐ1máKmbar á l ; cm3ÐÐÐÐÐÐÐ ÐÐÐÐ (NTP)ssW, kW, mWA á mÐ1TVásTkg, g, mgkg á sÐ1, kg á hÐ1, g á sÐ1see Table V in Sect. 93/19d =day (see Tab. 10.4.4see no. 73 and no. 103)3/63/7see also no.
1393/8H = Henryκ = cp á cvÐ13/93/103/11N = Newton3/123/133/143/15T = TeslaWb = Webersee no. 633/6172HomeStatutory unitsNo. VariableSymbolSIunitPreferred statutoryunits686970717273wiρi (ro-i)JλbiRkg á kgÐ1kg á mÐ3kg á m2mmol á kgÐ1JÐÐÐÐÐÐÐÐÐÐmol á Kkg molÐ1m3 á molÐ1m3 á molÐ1kgN á mÐ2kg á mÐ3N á mÐ2, Pam3N á mÐ2, Pasm3 á mÐÐÐÐÐÐÐÐÐs á m2 á barJásN á m á sÐ1NámmC á mÐ3srÐÐÐN á mÐ2, PaN á mÐ2, PaN á mÐ2, PaÐ%, o/oo, ppmkg á mÐ3, g á mÐ3, g á cmÐ3kg á m2m, cmmol á kgÐ1mbar á lÐÐÐÐÐÐÐÐÐÐmol á Kkg á kmolÐ1, g á molÐ1m3 á molÐ1, l á molÐ1m3 á molÐ1 (NTP)l á molÐ1 (NTP)gN á mmÐ2kg á mÐ3, g á cmÐ3mbarm3 (NTP), cm3 (NTP)mbars, ms, µscm2ÐÐÐÐÐÐÐÐs á mbarJásmbar á l á sÐ1mbar á lcm, mm, µmC á mÐ3, As á mÐ3srÐÐÐmbarmbarmbarÐN á mÐ2, PaN á m á sÐ1m3 á sÐ1N á mÐ2mbarmbar á l á sÐ1m3 á hÐ1, l á sÐ1N á mÐ2, N á mmÐ2102 Specific electron charge103 Specific gas constantpsqpV, QSρ, σ, τ(ro,sigma, tau)Ðe á meÐ1RiC á kgÐ1J á kgÐ1 á KÐ1104105106107108Specific ion chargeSpecific electrical resistanceSpecific volumeSpecific heat capacityStefan-Boltzmann constante á mÐ1ρ (ro)vcσ (sigma)109110111112Quantity of substanceThroughput of substanceConcentration of substanceCollision rateν (nŸ)qvciZC á kgÐ1Ωámm3 á kgÐ1J á kgÐ1 á KÐ1WÐÐÐÐÐÐm2 á K4molmol á sÐ1mol á mÐ3sÐ1C á kgÐ1, As á kgÐ1mbar á lÐÐÐÐÐÐÐÐkg á KC á kgÐ1, As á kgÐ1Ω á cm, Ω á mm2 á mÐ1m3 á kgÐ1; cm3 á gÐ1J á kgÐ1 á KÐ1, J á gÐ1 á KÐ1WÐÐÐÐÐÐm2 á K4mol, kmolmol á sÐ1mol á mÐ3, mol á lÐ1sÐ1Mass contentMass concentrationMoment of inertiaMean free pathMolalityMolar gas constant74 Molar mass (quantity-related mass)75 Molar volume76 Molar volume, standardMVmVmn7778798081828384Molecular massNormal stress (mech.)Standard density of a gasStandard pressureStandard volumePartial pressurePeriodPermeation coefficientmσ (sigma)ρn (ro-en)pnVnpiTP85868788899091929394959697Planck constantpV throughputpV valueRadius (also molecular radius)Space charge densitySolid angleRelative atomic massRelative molecular massRelative particle massResidual vapor pressureResidual gas pressureResidual (total) pressureReynold number nondimensionalvariableSaturation vapor pressureThroughput (of a pump)Pumping speedStress (mech.)hqpVpVrρ (ro)Ω (omega)ATMrMrprdprgprRe9899100101No.
of remarkin Section 10.3Notesppm = parts per millionsee Table V in Sect. 9see Table V in Sect. 9see Table V in Sect. 93/163/173/18see Table V in Sect. 93/193/193/203/21sr = steradiannondimensional variab.nondimensional variab.nondimensional variab.nondimensional variab.3/4see no. 132see no.
18see Table V in Sect. 93/223/23see Table V in Sect. 9for substance ãiÒ173HomeStatutory unitsNo. VariableSymbolSIunitPreferred statutoryunits113114115116117118119120121122123124125126127128129130131132133ConductanceFlow resistanceNumber of particlesParticle number density (volume-related)Particle number density (time-related)Particle throughput densityParticle massParticle fluxParticle flux densityThermodyn. temperatureTemperature differenceTemperature conductivityTotal pressureOverpressureAmbient pressureSpeed of light in vacuumEvaporation heatViscosity, dynamicVolumeVolume throughput (volumetric flow)Volume concentrationm3 á sÐ1s á mÐ3ÐmÐ3sÐ1mÐ2 á sÐ1kgsÐ1mÐ2 á sÐ1KKm2 á sÐ1N á mÐ2, PaN á mÐ2, PaN á mÐ2, Pam á sÐ1JPa á sm3m3 á sÐ1m3 á mÐ3m3 á sÐ1, l á sÐ1s á mÐ3, s á lÐ1ÐcmÐ3sÐ1mÐ2 á sÐ1, cmÐ2 á sÐ1kg, gsÐ1mÐ2 á sÐ1, cmÐ2 á sÐ1K, mKK, ¡C134135136137Volume-related collision rateQuantity of heatHeat capacityThermal conductivityC, German: LRNnqNjNmqNjNT∆T, ∆ϑaptpePambcLdη (eta)Vqvσi(sigma-i)ZvQCλ(lambda)α (alpha)138 Heat transfer coefficient139 Path length140 Wave length141 Angle (plane)142 Angular acceleration143 Angular velocity144 Efficiency145 Time146 Period of timesλ (lambda)α, β, γ rad(alpha,beta, gamma)α (alpha)ω(omega)η (eta)tt, ∆tNo.
of remarkin Section 10.3Notesnondimensional variab.see no. 120see no. 121see no. 117see no. 1183/24a = λ á ρÐ1 á cpmbarmbarmbar, barm á sÐ1, km á sÐ1kJmPa á sm3, l, cm3m3 á hÐ1, l á sÐ1l á lÐ1, %, o/oo, ppmsÐ1 á mÐ3JJ á KÐ1WÐÐÐÐÐKámWÐÐÐÐÐÐK á m2mmradsÐ1 á mÐ3, sÐ1 á cmÐ3J, kJ, kWh, WsJ á KÐ1, kJ á KÐ1WÐÐÐÐÐÐKámm, cmnmrad, ¡, Ô, ÔÕrad á sÐ2rad á sÐ1rad á sÐ2rad á sÐ1ÐssÐs, min, h, nn, mns, min, h3/33/33/3see Table V in Sect.
9see no. 20ppm = parts per million3/253/113/26rad = radiannondimensional variab.see Table 10.44see Table 10.44174HomeStatutory units10.3 Remarks on alphabetical list inSection 10.23/1: ActivityThe unit previously used was curie (Ci).3/5: Dynamic viscosityThe unit previously used was poise (P).1 P = 0.1 Pa á s = 1 g á cmÐ1 á sÐ11 Ci = 3.7 á 1010 á s-1 = 37 ns-13/5a: Energy doseRad (rd) is no longer permissible.3/2: (¡C) Celsius temperatureThe term degrees Celsius is a special name for the SI unit kelvin (K) [seeno. 122] for indicating Celsius temperatures.
The term degrees Celsius islegally approved.11 rd = ÐÐÐÐ J á kgÐ11003/3: PressureThe revised version of DIN 1314 must be complied with. The specificationsof this standard primarily apply to fluids (liquids, gases, vapors). In DIN1314, bar (1 bar = 0.1 MPA = 105 Pa) is stated in addition to the (derived)SI unit, 1 Pa = 1 N á m-2, as a special name for one tenth of a megapascal(Mpa). This is in accordance with ISO/1000 (11/92), p. 7. Accordingly themillibar (mbar), a very useful unit for vacuum technology, is alsopermissible: 1 mbar = 102 Pa = 0.75 torr. The unit ÒtorrÓ is no longerpermissible.Special noteExclusively absolute pressures are measured and used for calculations invacuum technology.In applications involving high pressures, frequently pressures are used thatare based on the respective atmospheric pressure (ambient pressure) pamb.According to DIN 1314, the difference between a pressure p and therespective atmospheric pressure (ambient pressure) pamb is designated asoverpressure pe: pe = p Ð pamb.
The overpressure can have positive ornegative values.Conversions1 kg á cm-2 = 980.665 mbar = 981 mbar3/6: WeightDIN 1305 is to be complied with in this context. Because of its previousambivalence, the word weight should only be used to designate a variableof the nature of a mass as a weighing result for indicating quantities ofgoods.The designations Òspecific weightÓ and Òspecific gravityÓ should no longer beused. Instead, one should say density.3/7: Weight forceSee DIN 1305.
The previous units pond (p) and kilopond, i.e. kilogramforce, (kp) as well as other decimal multiples of p are no longer used.1 kp = 9.81 N3/8: Ion doseThe previously used unit was the Ršntgen (R). 1 R = 2,58 á 10Ð4 C á kgÐ13/9: Kinematic viscosityThe previously used unit was stokes (St).1 St = 1 cm2 á sÐ1; 1 cSt = 1 mm2 á sÐ13/10: ForceThe dyne, the CGS unit for force, is no longer used.1 dyne = 10-5 N1 at (technical atmosphere) = 980.665 mbar = 981 mbar1 atm (physical atmosphere) = 1013.25 mbar = 1013 mbar1 atmosphere above atmospheric pressure (atmospheric overpressure) =2026.50 mbar = 2 bar1 atm1 torr = 1 mm Hg = ÐÐÐÐÐÐ = 133.322 Pa= 1.333 mbar7601 meter head of water = 9806.65 Pa = 98 mbar3/11: Length/wavelengthThe unit •ngstršm (•) (e.g.
for wavelength) will no longer be used in future(see Table 4.6).1 • = 10-8 cm = 0.1 nmThe pressure as mechanical stress (strength) is generally given in pascal(Pa) and in N á nmÐ2.3/12: Leak rateIn DIN 40.046 sheet 102 (draft of August 1973 issue), the unitmbar á dm3 á s-1 (= mbar á l á s-1) is used for the leak rate. Note that the leakrate corresponding to the unit 1 mbar á l á s-1 at 20 ¡C is practically thesame as the leak rate 1 cm3 á s-1 (NTP). (See also 3/17)Conversions:1 Pa = 1 N á mÐ2 = 10Ð6 N á mmÐ23/13: Magnetic field strengthThe previously used unit was the oersted (Oe).1 kg á cmÐ2 = 98,100 Pa = 0.981 N á mmÐ2 = 0,1 N mmÐ21 Oe = 79.577 A á m-11 mm Hg = 133.332 Pa = 1.333 mbar = 4/3 mbar1 kg á mmÐ2 = 9,810,000 Pa = 9.81 N á mmÐ2 = 10 N á mmÐ2175HomeStatutory units3/14: Magnetic flux densityThe previously used unit was the gauss (G).1 G = 10-4 Vs á m-2 = 10-4 T (T = Tesla)3/15: Magnetic fluxThe previously used unit was the maxwell (M).1 M = 10-8 Wb (Weber)3/16: Standard volumeDIN 1343 must be complied with.The designation m3 (NTP) or m3 (pn, Tn) is proposed, though theexpression in parentheses does not belong to the unit symbol m3 but pointsout that it refers to the volume of a gas in its normal state(Tn = 273 K, pn = 1013 mbar).3/17: Partial pressureThe index ÒiÓ indicates that it is the partial pressure of the Òi-thÓ gas that iscontained in a gas mixture.3/18: Gas permeabilityThe permeation coefficient is defined as the gas flow m3 á s-1 (volumetricflow pV) that goes through a fixed test unit of a given area (m2) andthickness (m) at a given pressure difference (bar).According to DIN 53.380 and DIN 7740, Sheet 1, supplement, the gaspermeability (see no.
40) is defined as Òthe volume of a gas, converted to0 ¡C and 760 torr, which goes through 1 m2 of the product to be tested at acertain temperature and a certain pressure differential during a day(= 24 hours)Ó.3/19: pV throughput/pV valueDIN 28.400, Sheet 1 is to be taken into account here. No. 86 and no. 87have a quantitative physical significance only if the temperature is indicatedin each case.3/20: Relative atomic massMisleadingly called Òatomic weightÓ in the past!3/24: Temperature differenceTemperature differences are given in K, but can also be expressed in ¡C.The designation degrees (deg) is no longer permissible.3/25: Quantity of heatThe units calorie (cal) and kilocalorie (kcal) are no longer be used.1 kcal = 4.2 kJ3/26: Angle1 radian (rad) is equal to the plane angle which, as the central angle of acircle, cuts out an arc having a length of 1 m from the circle.
See also DIN1315 (8/82).π1¡ = ÐÐÐÐÐ rad: 1Õ = 1¡/60; 1ÕÕ = 1Õ/60.180360¡1 rad = ÐÐÐÐÐ á 60¡2π10.4 Tables10.4.1 Basic SI unitsBasic unitSymbolVariableÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑÑmetermlengthkilogrammkgmasssecondstime, period; durationampereAelectric currentkelvinKthermodyn. temperaturemolemolquantity of substancecandelacdluminous intensity3/21: Relative molecular massMisleadingly called Òmolecular weightÓ in the past!3/22: Specific gas constantAs mass-related gas constant of the substance ÒiÓ. Ri = Rm ( Mi-1; Mi molarmass (no. 74) of the substance ÒiÓ.
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