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151.
Nonequilibrium model for steady state simulation of catalytic distillation is presented. Mathematical model takes into account
both mass and heat transfers across the gas liquid interface and through the liquid-solid (catalyst) interface. Equations
describing the mentioned phenomena are based on the effective diffusivity approach. The resulting system of nonlinear algebraic
equations was implemented in the FORTRAN programming language and solved by the BUNLSI (Ferraris & Tronconi, 1986) solver.
The described model was verified using the experimental data obtained from a continuous distillation column equipped with
catalytic packing. As an experimental model system, synthesis of propyl propionate from propan-1-ol and propionic acid was
chosen. Comparison of experimental and simulation data is presented, and appropriateness of the developed model for other
types of catalytic distillation processes is discussed.
Presented at the 35th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 26–30 May
2008. 相似文献
152.
153.
Ion Gutiérrez-Aguirre Marko Banjac Andrej Steyer Mateja Poljšak-Prijatelj Matjaž Peterka Aleš Štrancar Maja Ravnikar 《Journal of chromatography. A》2009,1216(13):2700-2704
Rotaviruses are the leading cause of diarrhoea in infants around the globe and, under certain conditions they can be present in drinking water sources and systems. Ingestion of 10–100 viral particles is enough to cause disease, emphasizing the need for sensitive diagnostic methods. In this study we have optimized the concentration of rotavirus particles using methacrylate monolithic chromatographic supports. Different surface chemistries and mobile phases were tested. A strong anion exchanger and phosphate buffer (pH 7) resulted in the highest recoveries after elution of the bound virus with 1 M NaCl. Using this approach, rotavirus particles spiked in 1 l volumes of tap or river water were efficiently concentrated. The developed concentration method in combination with a real time quantitative polymerase chain reaction assay detected rotavirus concentrations as low as 100 rotavirus particles/ml. 相似文献
154.
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155.
156.
Starting from the Strassen method for rapid matrix multiplication and inversion as well as from the recursive Cholesky factorization algorithm, we introduced a completely block recursive algorithm for generalized Cholesky factorization of a given symmetric, positive semi-definite matrix A∈Rn×n. We used the Strassen method for matrix inversion together with the recursive generalized Cholesky factorization method, and established an algorithm for computing generalized {2,3} and {2,4} inverses. Introduced algorithms are not harder than the matrix–matrix multiplication. 相似文献
157.
158.
Saario SM Palomäki V Lehtonen M Nevalainen T Järvinen T Laitinen JT 《Chemistry & biology》2006,13(8):811-814
Previous studies indicate that in brain tissue the endocannabinoid 2-AG is inactivated by monoglyceride lipase (MGL)-catalyzed hydrolysis, and a recent report has indicated that MGL activity could be specifically inhibited by URB754 . In the present study, URB754 failed to inhibit 2-AG hydrolysis in rat brain preparations. In addition, brain cryosections were employed to assess whether URB754 could facilitate the detection of 2-AG-stimulated G protein activity. Nevertheless, whereas pretreatment with PMSF readily allowed detection of 2-AG-stimulated G protein activity, URB754 was ineffective. In contrast to previous claims, brain FAAH activity was also resistant to URB754. Thus, in our hands URB754 was not able to block the endocannabinoid-hydrolyzing enzymes and cannot serve as a lead structure for future development of MGL-specific inhibitors. 相似文献
159.
Haertelt M Fielicke A Meijer G Kwapien K Sierka M Sauer J 《Physical chemistry chemical physics : PCCP》2012,14(8):2849-2856
Structural information for neutral magnesium oxide clusters has been obtained by a comparison of their experimental vibrational spectra with predictions from theory. (MgO)(n) clusters with n = 3-16 have been studied in the gas phase with a tunable IR-UV two-color ionization scheme and size-selective infrared spectra have been measured. These IR spectra are compared to the calculated spectra of the global minimum structures predicted by a hybrid ab initio genetic algorithm. The comparison shows clear evidence that clusters of the composition (MgO)(3k) (k = 1-5) form hexagonal tubes, which confirm previous theoretical predictions. For the intermediate sizes (n≠ 3k) cage-like structures containing hexagonal (MgO)(3) rings are identified. Except for the cubic (MgO)(4) no evidence for bulk like structures is found. 相似文献
160.
We establish some results on coincidence and common fixed points for a twopair of multi-valued and single-valued maps in complete metric spaces.Presented theorems generalize recent results of Gordji et... 相似文献