the molecular sieves are selective adsorbents. they can adsorb some kind of molecules that are different in size or shape from the others. in separation of n-paraffins from iso-paraffins and aromatics, sa molecular sieve is the suitable adsorbent, and can adsorb n-paraffins to separate them from other hydrocarbons. in this paper equilibrium isotherms of n-cs, n-c6 and n-c7 from an inert solvent...

Adsorption of p-Nitrophenol by three different activated carbons (F100, S.E.I. and B.D.H.) was carried out at 301 K and at controlled pH conditions. Two different adsorption models (Langmuir model and Freundlich model) were studied and compared. The adsorption capacity of the carbons depends on the Point of Zero Charge (PZC) and surface area of the carbons. Adsorption of the solute at higher pH...

Optical second harmonic generation (SHG) is used as a noninvasive probe of two-dimensional (2D) ferroelectricity in Langmuir-Blodgett (LB) films of copolymer vinylidene fluoride with trifluorethylene. The surface 2D ferroelectric-paraelectric phase transition in the topmost layer of LB films and a thickness independent (almost 2D) transition in the bulk of these films are observed in temperatur...

Modulated Langmuir waveforms have been observed by several spacecraft in various regions of the heliosphere, such as the solar wind, the electron foreshock, the magnetotail, or the auroral ionosphere. Many observations revealed the bursty nature of these waves, which appear to be highly modulated, localized, and clumped into spikes with peak amplitudes typically 3 orders of magnitude above the ...

Thermodynamic studies on the bioadsorption of Cr(III) onto Agave lechuguilla biomass were conduced. The experimental results at different temperatures were modeled using the Langmuir and Freundlich isotherms to obtain the characteristic parameters of each model. Both the Freundlich and Langmuir models were found to represent the bioadsorption process. The average adsorption capacities calculate...

Naturally Enhanced Ion Acoustic Lines (NEIALs) detected with Incoherent Scatter Radars (ISRs) can be produced by a Langmuir decay mechanism, triggered by a bump on tail instability. A recent model of the beam-plasma instability suggests that weak-warm beams, such those associated with NEIAL events, might produce Langmuir harmonics which could be detected by a properly configured ISR. The analys...

We describe a gradient flow structure for the inviscid Langmuir layer Stokesian subfluid model introduced recently by Alexander et al [1].

Langmuir films behavior of asymmetric glycerol dialkyl nonitol tetraether (GDNT) lipids at the air-water interface (temperature 19 ̊C ± 1 ̊C) investigated the stability of the mean ratio of Langmuir films for different spreading time prior to the transfer film. Floating monolayer films stability is an important parameter to obtain high-quality Langmuir-Blodgett films for their aplications. Hyster...