The radial distribution of the axial component of time-average liquid velocityand turbulent
intensity in a gas-liquid bubble column was investigatedexperimentally using LaserDoppler
Anemometer (LDA). The effects of operating parameters on liquidturbulent intensity
arestudied and an empirical relationship between turbulent intensity andviscosity was
established. Such a relationship can be used convenientlyin the calculation of
liquidvelocity profiles in bubble columns.

Overall dispersed side volumetric mass transfer coefficients forprotein and amino acids
were measured in continuous countercurrentPEG4000/KHP aqueous two-phase systems in a 57 mm
I.D. packed extractioncolumn. A model for overall dispersed side volumetric mass
transfercoefficients was derived by describing the motion of the drops based uponNavier-
Stokes equation combined with the relationship between mass transfercoefficients and the
drop velocity. The model provides good predictions andcan be successfully used in aqueous
two-phase extraction. The averagerelative deviation between calculated values and
experimental data rangesfrom 8% to 14%.

A starved feed reactor (SFR) is a semi-batch polymerization reactor where initiator and
monomer are fed slowlyinto a fixed amount of solvent. The polymerization is carried out
isothermally at elevated temperatures. The added initiatordecomposes instantaneously and
the added monomer polymerizes immediately. The molecular weight (MW) and molecularweight
distribution (MWD) of the product polymer can be effectively controlled by the feed ratio
of monomer to initiator. Thispaper presents a study on the MWD of styrene polymerization in
a SFR. The MWD model parameters are regressed withexperimental data. Although the solids
fraction in the SFR is high(higher than 50%), viscosity is not too high and the "gel
effect"is weak due to the low molecular weight of the products. It is found that the
termination rate constant is a power function ofmolecular weight, radicals terminate via
100% combination, the thermal initiation can be neglected even at high reactiontemperature
studied. And calculated results indicate that in the SFR,the validity of the long chain
assumption becomes doubted. It appearsthat other alterative assumption should be found for
an improved model.

A generalized rate model for free radical copolymerization was proposed.It can be applied
not only to the system with the participation ofcharge-transfer complex (CTC), but also to
the system without theparticipation of CTC. The effects of equilibrium constant, total
monomerconcentration, homo-propagation parameters and reactivity ratios on freemonomer,
CTC, overall rates, and the contribution of CTC were consideredin the simulation. North
equation of copolymerization rate as a specialcase can be derived from the generalized
model.

Experiments were conducted on a trickle bed with 0.283 m ID toelucidate the relation-ship
between hysteretic phenomena and liquiddistribution. The hysteresis of pressure drop and
the variance of radialliquid distribution were observed simultaneously. Residence time
distribution(RTD), holdup and mean residence time (RT) of liquid phase were alsofound to
demonstrate hysteresis of the same nature. RTD, liquid holdupand mean RT calculated with a
simple model from the distribution ofliquid flow rate show characteristics consistant with
the experimentaldata, suggesting that the hyteretic phenomena originate from
themultiplicity and nonuniformity of liquid flow distribution.

Fouling induction period of CaCO3 on heated surface was studied with themicro video
technology. The rates of nucleating and nuclei growing weremeasured under various
experimental conditions. The experimental resultsshowed that both nucleating and nuclei
growing rates of CaCO3 increased obviouslywith surface temperature and concentration of
reagents. In addition, theexperiment of fouling induction period on the surface material of
chemicalplated nickel-phosphorus-polytetrafluoroethylene indicated that not only
thenucleate rate of CaCO3 decreased but also some fouling particles with certainsize were
easy to peel off from the heated surface under shearing stress,which means that the
property of surface material is one of the most importantfactors influencing fouling
induction periods.

A new approach to the investigation of vdW type of equations of state (EOS)is developed by
embedding a vapor pressure equation and a saturated liquidvolume equation into vdW type
EOS, which results in a new function As(T). The As(T)possesses the properties of an
attractive parameter A(T), and if an EOS isaccurate in the whole PVT space, then its
numerical value equals A(T). As auseful tool for investigating EOS, the As(T) has been used
to makecomparisonsamong RKS, PRSVII, PT and ALS EOS, and to indicate where the
shortcomingsof the EOS are coming from. Based on the As(T), a possible way to develop a
realpredictive equation of state is also suggested.

In this paper the desorption kinetics of volatile in condensed modepolyethylene process is
studied through experiments. It is found thatthough the residual volatile in particles at
the later stage of desorptionaccounts for a relatively small portion of the total quantity,
the desorptionof this part of volatile requires much longer time than at the earlier
stage.For high requirement of devolatilization, the total time needed will bepredominately
determined by the residual amount of volatilein particles. Temperature has greater effect
on the desorption rate thanother influence factors, especially in the later period of
desorption.A model is proposed to calculate the volatile desorption rate for condensedmode
polyethylene process.

The growth of filamentous microorganism is contributed by tipextension and branching. The
microscopic growth of filamentousmicroorganism means the growth process from one or a few
spores.In order to describe the microscopic process, a populationmorphologically structured
model is proposed, in which three morphologicalcompartment andtheir interactions were
considered, and the heterogeneity of hyphal growthwas included. The model was applied to
describe the microscopic growth of Streptomyces tendae and Geotrichum candidum with good
agreement. From modelprediction, it is concluded that if the number of hyphae is large
enough(macroscopic growth), the specific growth rate of filamentous microorganismand the
ratio of morphological forms in hyphae will become constant.

Experimental data are presented for the void fraction and theshear stresses of stratified
gas-liquid flow in a pipe. A new techniquewas used to measure the interface shear stress.
The interfacial shearstress was determined by using two methods: a momentum balance of
gasand an extrapolation of the Reynolds shear stress profile at the gas-liquidinterface. A
new formula , relating to the interfacial friction factor withthe void fraction and
superficial gas Reynold number, was developed to predict the interface shear stress . The
predicted values are in good agreement withexperimental data.