Apiezon L, M and

ANTU, 1-naphthyl thiourea Apiezon L, M and T Aqua regia Arterenol... 

Di-poly Aldehydes (and ketones) FFAP QF-I, Porapak-Q, Porapak-QS Apiezon L, M carbowax 400, 750, 1000, 1500, 1540 di-n-butyl phthalate diethylene glycol succinate ethylene glycol succinate Hallcomid M18 squalene tricresyl phosphate 1,2,3-tris (2-cyanoethoxy) propane Ucon series... 

Do not use paints, glues, or other goos without careful consideration of their effect on vacuum integrity. Apiezon vacuum greases L, M, and N have a long history as reliable lubricants with low outgassing rates, and Apiezon Wax W ( Black Wax ) and Q Compound are useful as short-term solutions for leaks when dismantling for more permanent repair is not practical. 

Lubrication of all ground glass surfaces is essential for distillations under reduced pressure. Suitable lubricants are Apiezon grease L, M or N and Silicone stopcock grease also Alkathene (a polyethylene plastic), which is especially suitable for high temperatures. 

On a 2-m- gas chromatography column packed with 10% Apiezon L and heated to 100°, the retention times for N,N-dimethylcyclohexylamine and cyclohexanol are 15 and 4 minutes, respectively. The composition of this forerun is 80-85% of the amine and 20-15% of the alcohol. 

Sampling. Four aerosol samples were collected isokinetically on July 26, 1979, at ports on the inlet duct of the ESP at Plant A two were taken with 62-mm fluoropore filters and two were taken with the University of Washington MKV Cascade impactor (1 ). At plant D, samples were collected over a 6-day period at ports both in the outlet duct of the ESP (i.e., upstream of the FGD system) and at the 91-m level of the stack. Eleven fluoropore filter, 1 MKV, and 4 MKIII impactor samples at each location, giving a total of 22 filter, and 8 MKIII samples. A single MKV sample was also collected in-stack at reduced pressure at plant D during the 6-day period. Polycarbonate material coated with apiezon L vacuum grease and 62 or 47-mm-diam, l-pm pore Fluoropore filters were used as back-up filters in the MKV impactor. 

After 1 hour, the reaction is complete as monitored by gas chromatographic analysis on an Hewlett-Packard F M 5751 research chromatograph (1.85 m. x 0.313 cm. stainless-steel column of 10% Apiezon L on Chromosorb W AW/DMCS column temperature 250°). Thin-layer chromatography was found to be of little use in monitoring the reaction, as the Rf values for benzyl disulfide and benzyl sulfide are virtually identical for a variety of solvent systems tried. Proton magnetic resonance (benzene) shows that these two compounds have coincidental chemical shifts for the benzylic protons 8 3.4 (singlet). 

Figure 24-10 Comparison of (a) isothermal (constant temperature) and ( >) programmed temperature chromatography. Each sample contains linear alkanes run on a 1.6-mm-diameter x 6-m-long packed column containing 3% Apiezon L (liquid phase) on 100/120 mesh WarAport 30 solid support with He flow rate of 10 mL/min. Detector sensitivity is 16 times greater in panel a than in panel b. [From H. M McNair and E. J. Bonelli, Basic Gas Chromatography (Palo Alto. CA Varian Instrument Division. 1968).]...

Langer and co-workers [24,25] converted alcohols and phenols prior to GC analysis into TMS ethers by the action of HMDS. The method using silylation with HMDS—TMCS (2 1) was used for the GC of ethylene and diethylene glycols on Apiezon L [26], glycerol on SE-30 [27], polyethers of glycols on XE-61 [28], hydroxystilbenes on SE-52 [29], some flavonoides and related substances on SE-30 [30], plant phenols and related substances on OV-1, OV-17 and OV-25 [31], anthocyanines on OV-225 [32] and amino-chromes on SE-30 [33], Different terpene alcohols were silylated by Seidenstucker [34] within 10 min by heating at 40-60°C with a 6—8-fold excess of TMS-acetamide. The separation was performed on a stainless-steel column (50 m X0.25 mm I.D.) coated with Apiezon L. 

Mori et al. [87] analysed the components of polyamide resins by GC after silylation with the aid of BSA. About 10-mg portions of the samples are dissolved in 0.15 ml of acetonitrile in a 10-ml flask and 0.03 ml of triethylamine and 0.15 ml of BSA are added gradually. The flask is connected to a reflux condenser and heated at 90°C for 30 min with the elimination of the excess of air humidity. Another 0.15 ml each of BSA and acetonitrile are added gradually and the flask is heated for 30 min. The solution is then made up to a known volume with acetonitrile and 10 pi are injected into the gas chromatograph. Binding of the hydrochloric acid produced makes necessary the addition of triethylamine to the reaction mixture. In order to separate TMS derivatives, Mori et al. used a 2-m column packed with 5% of neopentyl glycol succinate on Celite 545 at 160°C, and a relative error of 4.4% was obtained for the quantitative analysis. The same column coated with SE-30 or Apiezon L failed. 

Column, glass, 1.2 m x 4 mm. Wash column and glass wool plugs with 5% (v/v) dichlorodimethyl silane in toluene (in a hood) before packing with 1 g Apiezon L/ 20 g 80 to 100 mesh Gas Chrom Q. Condition for 3 days at 200 °C at 10 mL Nj/min or until a steady baseline is obtained. Order of elution CSj, BHA, BHT, di-BHA. This column will separate the 2 and 3 isomers of BHA. 

The retention volume has been reported377 for triethyl and tetraethyl silanes on columns packed with silanized Chromosorb W supporting 20% of Apiezon L or 15% of Carbowax 20 M and operated at 120 and 90 °C, respectively, using helium as carrier gas and thermal conductivity or flame ionisation detection. Measurements were also carried out by gas-solid chromatography on columns of Carbochrom-1 (graphitized thermal carbon black with 0.1% of Apiezon L) or Silochrom C-80. 

Another instance where the choice of column is critical is with 6-0-methyl-D-galactitol (1-O-methyl-L-galactitol) pentaacetate and jS-n-galactopyranose pentaacetate, which are not separated on a column of 20% of Apiezon M, but are resolved by a liquid phase containing 5% of Apiezon M and 1% of poly (ethylene ycol). ... 

Standard partial molar free enthalpies, enthalpies, and entropies of vaporization from infinitely dilute solutions in Apiezon M were calculated from retention volumes determined over a range of temperatures data are listed for many organic and a few MR4 compounds (M = Si, Ge, and Sn), including Ge(C2H5)4 [29]. Apiezon L and two polar stationary phases were used in similar studies on a variety of MRr,R4 n compounds, yielding relative molar enthalpies and entropies of solution at 100°C referred to Si(CH3)4 as the standard [43]. Retention volumes and heats of solutions on two stationary phases have also been compared for M(C2H5)4 and M(C2H5)3H compounds with M = Si, Ge, and Sn [38]. 

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