Algorithm 540: PDECOL, General Collocation Software for Partial Differential Equations [D3]

Madsen, Niel K.; Sincovec, Richard F.

doi:10.1145/355841.355849

Cited by 288 publications

(98 citation statements)

References 8 publications

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“…Model equations [eqs (10) and (11)] were numerically solved by using the PDECOL package (Madsen and Sincovec, 1979) based on the method of orthogonal collocation in finite elements (OCFE). There are four PDEs for each zone of the TMB.…”

Section: Resultsmentioning

confidence: 99%

Separation of 1,1′-bi-2-naphthol enantiomers by continuous chromatography in simulated moving bed

Pais

Loureiro

Rodrigues

1997

Chemical Engineering Science

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Abstract--The chromatographic separation of 1,1'-bi-2-naphthol enantiomers with 3,5-dinitrobenzoyl phenylglycine bonded to silica gel stationary phases is studied. Continuous chromatography in simulated moving bed (SMB) is analyzed by modeling, simulation and operation of a SMB pilot unit Licosep 12-26 from Separex (France).A model for the prediction of the cyclic steady-state performance of the SMB is developed based on the analogy with the true moving bed (TMB). The model assumes axial dispersion flow for the liquid phase, linear driving force (LDF) approximation for intraparticle mass transfer rate and takes into account multicomponent adsorption equilibria.The SMB package allows the simulation of the pilot unit. The effect of operating variables (switching time, extract and feed flow rates, section length) and number of mass transfer units on the SMB performance is analyzed. The SMB performance is characterized by purity, recovery, solvent consumption and adsorbent productivity. The package also allows the simulation of the dynamic evolution of internal profiles for the transient operation of a TMB. The operation of the SMB pilot unit was carried out for the separation of racemic mixtures of bi-naphthol enantiomers. Using a 8-column configuration purities as high as 94.5% of the more retained species in the extract and 98.9% of the less retained species in the raffinate were obtained.

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Section: Resultsmentioning

confidence: 99%

Separation of 1,1′-bi-2-naphthol enantiomers by continuous chromatography in simulated moving bed

Pais

Loureiro

Rodrigues

1997

Chemical Engineering Science

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“…A collocation on finite elements method [35] was used to solve the non-linear parabolic partial differential equations (PDE) with the initial and boundary conditions for each model equation.…”

Section: Homogeneous Diffusion Modelmentioning

confidence: 99%

“…(15) in conjunction with the initial and boundary conditions, Eqs. (29)(30)(31), were solved by the PDECOL package [35], where y f ( ,Â) is obtained by solving Eq. (17) and the equilibrium is given by the mass action law (Eq.…”

Section: Regenerationmentioning

confidence: 99%

Cadmium uptake by algal biomass in batch and continuous (CSTR and packed bed column) adsorbers

Vilar¹,

Santos²,

Martins³

et al. 2008

Biochemical Engineering Journal

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a b s t r a c tIn this work, the properties of marine algae Gelidium, algal waste from agar extraction industry and a composite material were investigated for cadmium(II) biosorption. Equilibrium experiments were performed at three pH values (4, 5.3 and 6.5). Equilibrium data were well described by the Langmuir and Langmuir-Freundlich isotherms. Two models predicting the pH influence in the cadmium biosorption (discrete and continuous models) have been developed in order to better describe the equilibrium. The continuous model also considers a heterogeneous distribution of carboxylic groups, determined by potentiometric titration. The results of batch kinetic experiments performed at different pH values were well fitted by two mass transfer models and the homogeneous diffusion coefficients for the cadmium ions inside the biosorbent were obtained. Continuous stirred tank reactor (CSTR) and packed bed column configurations were also examined for the biosorption of cadmium ions. A strong acid (0.1 M HNO 3 ) was used as eluant to regenerate the biosorbents in the column. Several mass transfer models were applied with success to describe the biosorption process in batch mode, CSTR and fixed bed column.

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“…System of equations (2) was solved using a stiff partial differential equation solver PDETWO [19]. Figure 3 shows typical single pulse voltage and current oscillograms in a M=3 nitrogen flow at P 0 =250 torr, Ptest=8.4 torr, respectively, at the magnetic field of B=1.5 T. The peak voltage and current at these conditions are 13.2 kV and 31.2 A, respectively, with pulse duration (FWI{M) of approximately 30 ns.…”

Section: Discharge Modelmentioning

confidence: 99%

MHD Flow Control and Power Generation in Low-Temperature Supersonic Flows

Nishihara

Rich

Lempert

et al. 2006

37th AIAA Plasmadynamics and Lasers Conference

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The public reporting burden for this collecbon of information is esbmated to average 1 hour per response. including the time for reviewing instructions, searching existing data sources. galhenng and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden. Approved for public release; distribution unlimited. SUPPLEMENTARY NOTES ABSTRACTReport developed under STTR contract for topic AF05-TO1 6. Results of cold MHD flow deceleration and MHD power-generation experiments conducted at The Ohio State University are presented. MHD effect on the flow is detected from flow static-pressure measurements. The observed static-pressure change is due to the MHD interaction and not Joule heating of the flow in the crossed discharge. Comparison of experimental results with modeling calculations shows that the retarding Lorentz force increases the static-pressure rise produced by Joule heating of the flow, while the accelerating Lorentz force reduces the pressure rise. The experiments show that at the present conditions, the electric current in the MHD power-generation regime is very low, on the order of 1 mA. This is entirely due to the bottleneck effect of the discharge cathode layer at conditions where the MHD open voltage is significantly lower than the cathode-voltage fall. Modeling calculations demonstrate that (1) at the flow conductivities currently achieved in low-temperature MHD flows (a -0.1 mho/m), low open voltages reduce the MHD currents by more than two orders of magnitude, and (2) this effect cannot be circumvented by seeding the flow at feasible levels (-0.1%) or using electrodes with a high secondary-emission coefficient. SUBJECT TERMS STTR

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Algorithm 540: PDECOL, General Collocation Software for Partial Differential Equations [D3]

Cited by 288 publications

References 8 publications

Separation of 1,1′-bi-2-naphthol enantiomers by continuous chromatography in simulated moving bed

Separation of 1,1′-bi-2-naphthol enantiomers by continuous chromatography in simulated moving bed

Cadmium uptake by algal biomass in batch and continuous (CSTR and packed bed column) adsorbers

MHD Flow Control and Power Generation in Low-Temperature Supersonic Flows

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