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Deactivation separable

As already mentioned UlFO, Usl, and Uso are variable DC-sources. Their settings are optimized for each chip individually with respect to maximum ion throughput at deactivated separator. This follows the algorithm ... [Pg.449]

Do we expect this model to be accurate for a dynamics dictated by Tsallis statistics A jump diffusion process that randomly samples the equilibrium canonical Tsallis distribution has been shown to lead to anomalous diffusion and Levy flights in the 5/3 < q < 3 regime. [3] Due to the delocalized nature of the equilibrium distributions, we might find that the microstates of our master equation are not well defined. Even at low temperatures, it may be difficult to identify distinct microstates of the system. The same delocalization can lead to large transition probabilities for states that are not adjacent ill configuration space. This would be a violation of the assumptions of the transition state theory - that once the system crosses the transition state from the reactant microstate it will be deactivated and equilibrated in the product state. Concerted transitions between spatially far-separated states may be common. This would lead to a highly connected master equation where each state is connected to a significant fraction of all other microstates of the system. [9, 10]... [Pg.211]

Chromium (ITT) can be analy2ed to a lower limit of 5 x 10 ° M by luminol—hydrogen peroxide without separating from other metals. Ethylenediaminetetraacetic acid (EDTA) is added to deactivate most interferences. Chromium (ITT) itself is deactivated slowly by complexation with EDTA measurement of the sample after Cr(III) deactivation is complete provides a blank which can be subtracted to eliminate interference from such ions as iron(II), inon(III), and cobalt(II), which are not sufficiently deactivated by EDTA (275). [Pg.274]

Desalting is a water-washing operation performed at the production field and at the refinery site for additional cmde oil cleanup. If the petroleum from the separators contains water and dirt, water washing can remove much of the water-soluble minerals and entrained soflds. If these cmde oil contaminants are not removed, they can cause operating problems duting refinery processiag, such as equipment plugging and corrosion as well as catalyst deactivation. [Pg.201]

Many forms of chromatography have been used to separate mixtures of quinoline and isoquinoline homologues. For example, alumina saturated with cobalt chloride, reversed-phase Hquid chromatography, and capillary gas chromatography (gc) with deactivated glass columns have all been employed (38,39). [Pg.390]

Separated from retinol by column chromatography on water-deactivated alumina with hexane containing a very small percentage of acetone. Also chromatographed on TLC silica gel G, using pet ether/isopropyl ether/acetic acid/water (180 20 2 5) or pet ether/acetonitrile/acetic acid/water (190 10 1 15) to develop the chromatogram. Then recrystd from propylene at low temperature. [Pg.348]

The original microscopic rate theory is the transition state theory (TST) [10-12]. This theory is based on two fundamental assumptions about the system dynamics. (1) There is a transition state dividing surface that separates the short-time intrastate dynamics from the long-time interstate dynamics. (2) Once the reactant gains sufficient energy in its reaction coordinate and crosses the transition state the system will lose energy and become deactivated product. That is, the reaction dynamics is activated crossing of the barrier, and every activated state will successfully react to fonn product. [Pg.201]

The Ticona materials are prepared by continuous polymerisation in solution using metallocene catalysts and a co-catalyst. The ethylene is dissolved in a solvent which may be the comonomer 2-norbomene itself or another hydrocarbon solvent. The comonomer ratio in the reactor is kept constant by continuous feeding of both monomers. After polymerisation the catalyst is deactivated and separated to give polymers of a low residual ash content and the filtration is followed by several degassing steps with monomers and solvents being recycled. [Pg.280]

After deactivation and removal of the initiating system, the eoumarone-indene resin is separated from solvent and low moleeular weight materials by vacuum distillation. The removal of the low moleeular weight materials is important beeause they produce strong odour, they aet as softeners and they eause an undesirable deerease in softening point. Therefore, at this stage the softening point of the eoumarone-indene resins is adjusted. Finally, stabilizers are added to the liquid resin while it is still hot to inhibit further oxidation (whieh eauses diseolouration and odour). [Pg.605]

Polybutene resins. These liquid resins are obtained by cationic polymerization of petroleum C4 streams in the presence of AICI3 at relatively low temperature. Temperature and AICI3 concentration are important factors as they influence the molecular weight and viscosity of the final resin. After reaction, the mixture is deactivated with water, methanol, ammonia or aqueous sodium hydroxide. The organic layer is separated and distilled to remove solvent and unconverted material. [Pg.610]

A deactivated butane pressurized storage facility with two 750 m and two 1,6(X) m spheres was considered for partial activation of the two smaller spheres. A safety review showed that aspects of the facility did not comfily with with current standards of PETROBRAS regarding layout and separation. A PSA was performed with the following objectives ... [Pg.438]

Two serious drawbacks of this method are the extensive deuterium scrambling around the reaction site and the occasional formation of olefinic side products, which are hard to separate by conventional means. The extent of olefin formation may depend on the nature of the Raney nickel since it is known that desulfurization with deactivated Raney nickel can yield olefins. Best results are obtained when the deuterated Raney nickel is prepared very rapidly and used immediately after preparation. [Pg.171]

For many proteins, a simple buffer such as 0.1M phosphate, pH 7, produces excellent separations on SynChropak GPC columns. Generally, minimal interaction is achieved when the ionic strength is 0.05-0.2 M. To prevent denatur-ation or deactivation of proteins, the pH is generally kept near neutrality. For denatured proteins, 0.1% sodium dodecyl sulfate (SDS) in 0.1 M sodium phosphate, pH 7, is recommended. [Pg.315]

FIGURE 13.57 NOTE The importance of Solvent/column interaction using Jordi DVB columns cannot be over emphasized. We have found that a SOySO mbc of MeOH/ACN for the strong solvent Is adequate for many reverse phase separations and is better than either alone. We have now observed that the use of THF/ACN as strong solvent is often better than MeOH/ACN. In general Lewis bases (electron donor solvents) deactivate the aromatic rings and often dramatically increase column efficiencies. [Pg.400]

Deactivation of zeolite catalysts occurs due to coke formation and to poisoning by heavy metals. In general, there are two types of catalyst deactivation that occur in a FCC system, reversible and irreversible. Reversible deactivation occurs due to coke deposition. This is reversed by burning coke in the regenerator. Irreversible deactivation results as a combination of four separate but interrelated mechanisms zeolite dealu-mination, zeolite decomposition, matrix surface collapse, and contamination by metals such as vanadium and sodium. [Pg.72]

Solution "What is an immediate precursor of the target " The final step will involve introduction of one of three groups—chlorine, propyl, or sulfonic acid—so we have to consider three possibilities. Of the three, the chlorination of o-propylbenzene-sulfonic acid can t be used because the reaction would occur at the wrong position. Similarly, a Friedel-Crafts reaction can t be used as the final step because this reaction doesn t work on sulfonic acid-substituted (strongly deactivated) benzenes. Thus, the immediate precursor of the desired product is probably m-chloropropyl-benzene, which can be sulfonated to give a mixture of product isomers that must then be separated. [Pg.583]

Capillary column A narrow bore tube (0.25-1 mm ID) typically 30-100 m long (usually of deactivated fused silica), whose walls are coated with a liquid stationary phase to produce high-efficiency separations (N > 100,000). [Pg.360]


See other pages where Deactivation separable is mentioned: [Pg.464]    [Pg.1612]    [Pg.347]    [Pg.464]    [Pg.1612]    [Pg.347]    [Pg.564]    [Pg.595]    [Pg.45]    [Pg.584]    [Pg.410]    [Pg.413]    [Pg.39]    [Pg.522]    [Pg.12]    [Pg.480]    [Pg.174]    [Pg.292]    [Pg.2022]    [Pg.2057]    [Pg.574]    [Pg.574]    [Pg.610]    [Pg.83]    [Pg.66]    [Pg.79]    [Pg.379]    [Pg.7]    [Pg.52]    [Pg.305]    [Pg.18]    [Pg.230]    [Pg.258]    [Pg.264]    [Pg.265]    [Pg.99]    [Pg.100]   
See also in sourсe #XX -- [ Pg.216 ]




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