Search Results

You are looking at 1 - 10 of 2,961 items for :

  • "selectivity" x
  • Refine by Access: All Content x
Clear All

Abstract  

The derivative enthalpies of adsorption of m-xylene and p-xylene onto the NaY and BaY zeolites were measured at 150°C, then compared with those obtained at 25°C, and finally used to predict the selectivity of adsorption of xylene mixtures. Significant differences were observed as the temperature was elevated: for the NaY zeolite, the adsorbate-adsorbate interactions became prevalent, in contrast with the BaY zeolite, between zeolite and derivative interactions were stronger. The difference between the adsorption derivative enthalpies of the two xylenes displayed an abrupt variation from 2 molec. –1 for both zeolites, the filling from which selectivity towards m-xylene for the NaY zeolite and towards p-xylene for the BaY zeolite appeared. The preferentially adsorbed xylene was closely connected with the sense of this difference, which changed with the zeolite.

Restricted access

Waste Management 2007 27 1298 1305 A. Iriarte, X. Gabarrell, J. Rieradevall, LCA of selective

Restricted access
Orvosi Hetilap
Authors:
István Szabó
,
Zoltán Langmár
,
Zoltán Fontányi
,
Gábor Sobel
,
Máté Hazay
,
Ádám Galamb
,
Dóra Zergényi-Molnár
,
Péter Sziller
, and
Attila Pajor

Thurmond, A. S., Novy, M. J., Uchida, B. T. és mtsa: Fallopian tube obstruction: selective salpingography and recanalization. Radiology, 1987, 163 , 511–514. Uchida B. T. Fallopian

Open access
European Journal of Microbiology and Immunology
Authors:
M. M. Heimesaat
,
I. R. Dunay
,
D. Fuchs
,
D. Trautmann
,
A. Fischer
,
A. A. Kühl
,
C. Loddenkemper
,
A. Batra
,
B. Siegmund
,
H.-W. Krell
,
S. Bereswill
, and
O. Liesenfeld

P.T. Kovanen 1996 TNF-alpha and IL-1beta selectively induce expression of 92-kDa gelatinase by human macrophages J Immunol 157 4159 – 4165

Restricted access

diagnostic approach with two different selective agars for the screening for methicillin-resistant Staphylococcus aureus (MRSA) . Mil Med Res 2 , 18 ( 2015 ) 19. Micheel

Open access

Abstract  

The principles of selective separations by recrystallization are explained and formulae for the calculation of decontamination factors are presented. Experiments with strontium sulfate and radioactive strontium ions demonstrate the validity of the theoretical considerations. Similar or higher decontamination factors are found than those calculated for a uniform distribution of the radioactive strontium ions between crystals and solution. The high values are explained by assuming a recrystallization mechanism which consists of dissolution and redeposition of crystal layers. The half-times of recrystallization increase sharply with Sr2+ or SO 4 2− concentration in the solution. In nitric acid solutions as well as in mixtures containing nitrates and nitric acid the solubility of strontium sulfate is rather high, accordingly the decontamination factors are low under these conditions and furthermore the recrystallization half-times are long.

Restricted access

Introduction The selective hydrogenation of aromatic ketones to aromatic alcohols is an important reaction in the fine chemical industry [ 1 – 3 ]. So far, the hydrogenation of acetophenone has been successfully studied on Pd

Restricted access

number of highly cited clinical articles correlated with drug research success (assessed by expert judgment) even better than the number of all clinical articles. We have previously proposed a bibliometric indicator, the Top Journal Selectivity

Restricted access

In the present study, ethylbenzene dehydrogenation to styrene monomer over a potassium-promoted iron oxide catalyst in radial fixed bed reactor was simulated. The pseudo-heterogeneous model was employed to predict ethylbenzene conversion and selectivity of styrene monomer, toluene, and benzene. The simulation results showed that deactivation of catalysts causes reduction in the reaction zone; therefore, the ethylbenzene conversion decreases. It is proposed that, for compensating the conversion reduction, the feed temperature is increased 1 °C per 5 cm of deactivated length. Simulation results are in good agreement with the experimental data obtained from real plant.

Restricted access

hydroformylation [ 9 ]. Using biphasic systems in the hydroformylation of allylbenzene has been reported but it gives low selectivity towards linear aldehydes and some of them need harsh reaction conditions [ 10 – 12 ]. Low regioselectivity towards the

Restricted access