Column poison

The generally accepted method for separating sugars is to use an amino-bonded silica. However, an alternative method, whereby separations are achieved on a silica column dynamically modified with a long chain amine or a polyethylene amine is preferred since this system is far less susceptible to column poisoning . 

Column 8 gives the chemical reaction that may occur, whether it is exotlicrniie and poisonous. 

An analysis of the Poison cell method [4] is instructive. The concentration of the diffusant, C(t), in the receptor column of length h is measured at time t,... 

It is absolutely crucial that you preclean your sample. Any decomposed or insoluble material will stick to the top of the column and can continually poison further runs. There are a few ways to keep your column clean. 

Fig. 9. Indirect electrosynthetic process for the oxidation of anthracene to anthraquinone [10]. The charcoal column serves to remove organics which lead to corrosion and poisoning of the lead dioxide (Pb02) anode...

The makeup of fiesh A is added into the column as a liquid feed. This might be done so that any heavy impurities in this feed stream wilt go out the bottom of the column and not go into the reactor where they could cause catalyst poisoning. The makeup of fiesh A might be fed into the column because it contains both A and C, and it is desirable to let the column purify the stream so that it is richer in A. 

Hemoperfusion is like hemodialysis except that blood is circulated extracorporeally through a column with adsorbent material like resin or charcoal, which binds molecules electrostatically. The molecules likely to be removed are characterized as poorly dialyzable, lipid-soluble, protein bound. Among the indications for hemoperfusion in the management of poisoning include the presence of a poison in a patient with impairment of excretory system (i.e. damaged kidneys), intoxication of a drug known to produce delayed toxicity or metabolized to a more toxic metabolite (i.e. paraquat or methotrexate), deterioration of the clinical state of the poisoned patient despite conservative therapy (i.e. convulsions or cardiac arrhythmias following theophylline intoxication), or development of coma as a complication. 

Table II is a list of gases which could potentially interfere with an N0 analysis along with the concentrations of these gases which produce a signal equivalent to 1 ppm N0. Only H2S had an effect on sensor cell performance and was found to decrease the response level by 0.2 a/ppm. H2S, SO2 and NO2 were effectively filtered from the gas stream by use of triethanolamine (TEA) as shown in Table II. To prevent TEA vapors from reaching (and thus poisoning) the sensing electrode surface, a short column of a cation exchange bead was placed after the filter.

Interfacing HPLC or HPCE (capillary electrophoresis) to mass spectrometry is technically more complex than. with a GC because these techniques use a solvent that is often aqueous (water is a poison to mass spectrometers). The use of microcolumns in HPLC is desirable for coupling to MS because micro-columns operate at very low flow rates. They are also compatible with different ionisation techniques for the analysis of high molecular-weight species. 

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