Introduetion The vertiealU一shaPed boiling tubes are widely usedi一飞waste heat boilers,nuelear reaetorsteam generators,evaPorators and heat exehangers.Fo一instanee,waste heat boilers withU一shaPed tube are used in synthetie ammonia fertilizer Plants with daily outPut of a thousa一ldtons to reeover heat from high temPerature gas and ge,lerate 18Ot/h steam at 10.6 MPa.This 15 significant fo

The two一Phase flow and boiling heat tra一lsfer eharaeteristics in the bends ofU一shaPedtubes are eomPlieated beeause of the combined effeets of gravitational and eentrifugal Ibrees之连5 well as other factorsl sueh as seeondary flow ete.However,little researeh work in this re-sPeet has been eonducted uP to now. Lis et al.t’1 studied the flow and heat transfer behavior

Aeeident of tube failure in the waste heat boilers with vertiealU一shaPed tubes used insynthetie ammonia Plants oecurs frequently in oPeration.In order to find out the cause ofthe tube failure,and to Present the method of solution,investigations on two一Phase flowPattern in the bend of vertiealU一shaPed tubes and the wall temPerature behavior along the忱nd under the oPerating

Axial mixing reduces tlle driving foree of mass transfer and the plate effieieney of Columnused for mass transfer oPeration.Its effeet on the design and Performanee of RDC hasattraeted the attention of many researeh workers 50 that a number of PaPers〔,一’1 have beenPublished.Some of them found that the axial mixing of the continuous Phase would increaseby the flow of the

To date,most kinetie investigations ofC一aromaties hydroisomerization over bifunetionaleatalysts have been eoneerned with reaetjon meehanisms.R6bsehl巨ger et al.[,]studied thehydroisomerization kineties under sPecifie eonditions,and ProPosed a four一eomPonent reaetionseheme ineluding three xylene isomers and ethylbenzene.A signifieant amount of Cs一yelo-Paraffins 15,however

As deseribed in Part(I),Wei and Praterl’1,Prater et al.L,],and Silvestri et al.f3·‘1advaneed the rigorous analysis and the elegant framework of eomPlex reaetion system,Theirmethod,however,was aPPlied only to a few eases beeause of Iarge exPerimental expenses and1 imitations.In order to reduee the exPerimental efforts,Faitht,1 and Lombardot‘1 sug-gested some imProvements

Sodium ehloride 15 the main eomPonent in seawater,the imPortant raw material in manyindustrial systems and also the imPortant eonstituent under the earth,5 erust.In a Polarsolvent,NaCI 15 a tyPieal ionie eleetrolyte.50 the study of the thermodynamie ProPerties ofaqueous NaCI at high temPerature and high Pressure has not only some Praetieal signifieaneein ehemieal industry,oceanograPhy and