Mulls, for

The chiral arrangement of 80a molecules in the complex with (—)-12c is also easily detected by measurement of CD spectra as Nujol mulls. For example, the inclusion crystal of 80a with (—)-12c showed a (—)-Cotton effect, and that of 80a with (+)-12c showed a (+)-Cotton effect at around 260 and 310 nm, respec-... 

In the 8-azapurine series, IR spectra have been used mainly to provide reference data for compound identification or to confirm the presence of an attached group. Most of the recorded spectra refer to the solid state for which almost identical results have been obtained in KBr disks and Nujol mulls. For some spectra obtained in solution, see ref. 3. 

Nujol. Former TM for a mineral oil used to prepare mulls for infrared analysis. 

In Nujol mulls for phosphine complexes and liquid Xe26 or rare gas matrices27 for the pentacarbonyls. 

Bellomonte described a solid state IR assay procedure (KBr mull) for measuring dexamethasone in the presence of triamcinolone utilizing as analytical wavelengths 915 cm. - and 1140 cm. . ... 

Muller-type mixers have a wide range of application, from dry blends to sticky viscous materials. Extremely fluid mixes caimot be mulled for lack of sufficient friction to rotate the grinding wheels or mullers. 

L. J. Lohr and R. J. Kaier, Preparation of Micro Nujol Mulls for Infrared Analysis, Anal. Chem. 32, 301, 1960. 

Polymers, like powders, are solids at room temperature and in theory can be analyzed using KBr pellets or mulls. For hard polymers that can be ground into a powder, this works. However, polymers that are soft, rubbery, or too tough cannot readily be ground into powders and so are not easy to analyze. Fortunately, there exist techniques for turning polymers into thin films, which allows them to be analyzed in transmission as described below. 

Cl2C = CCl CCl =CCl2. Colourless viscous liquid b.p. 210-211 C. Principally used as a dispersant material for obtaining i.r. spectra of solids in mulls. Skin irritant. 

Nujol A trade name for a heavy medicinal liquid paraffin. Extensively used as a mulling agent in spectroscopy. 

Both cold- and warm-coating processes employ solutions of phenoHc resins. The principal process used for foundry resins is the hot-coating process. It is the fastest, least expensive, and safest process, and it requires no volatile removal. The sand is heated to 135—170°C in a muller, and soHd novolak resin in flake form is added, which melts quickly and coats the sand. A lubricant may be added at this point. After one minute of mulling, the batch is cooled by adding water, which evaporates rapidly. 

IR and Raman studies of heterocycles today cover two different fields. For simple and symmetrical molecules very elaborate experiments (argon matrices, isotopic labelling) and complex calculations lead to the complete assignment of the fundamentals, tones and harmonics. However, the description of modes ought to be only approximate, since in a molecule like pyrazole there are no pure ones. This means that it is not correct to write that the band at 878 cm is y(CH), and the only correct assertion is that the y(CH) mode contributes to the band. On the other hand, IR spectroscopy is used as an analytical tool for identifying structures, and in this case, bands are assigned to r-iCO) or 5(NH) on the basis of a simple Nujol mull spectrum and conventional tables. Both atttitudes, almost antagonistic to each other, are discussed in this section. 

Another rather extensive series of similar data, obtained using CS2 solutions and nujol mulls, has been published by Shindo (Fig. 4). His series include considerable data for jS-substituted compounds, for which the question of a choice of substituent constants does not arise. His data also show considerable scatter but seem to suggest strongly that <7+-values are indicated for + M substituents and normal <7-values for —M substituents. The conclusion is confirmed by the short series of similar data reported by Costa and Blasina and by Shupack and Orchin. The data of the latter authors for the NO frequencies in mws-ethylene pyridine N-oxide dichloroplatinum(II) complexes are also moderately well correlated with <7+-values. 

When the temperature takes an icy dive, my brain puts in a non-negotiable request for the toddy effect. I basically want to mull my body with heated spirits. 

Infrared (IR) investigations can be made on a sample of reactant previously heated to a known extent of reaction (a) and studied in the form of a mull or in an alkali halide disc. An alternative approach is to incorporate the reactant substance in a compact alkali halide disc [287] which is intermittently withdrawn from the reaction vessel for infrared measurements at appropriate intervals. Heated sample holders [288,289] permit repetitive scanning of the spectrum or continuous monitoring of a peak of interest during decomposition. 

Spectroscopic analysis of Pu5+ and Pu6+ halides is in its initial stages. No low-temperature single-crystal spectra have been reported. A 25°C mull spectrum of the compound Rb2PuF7 was described earlier (37), and is now supplemented by the results for CsPuFg (31) PuF gas-phase spectra have been reported by several different groups at ANL (38-39). 

Since solid-state reactions can easily be monitored by continuous measurement of spectra, it is easy to study the mechanism of the reactions. For this purpose, IR spectroscopy is the most useful, because IR spectra can be measured simply as Nujol mulls or directly for any mixture of solid-solid, solid-liquid, or liquid-liquid by using the ATP (attenuated total reflection) method. Some such examples of the mechanistic study are described. 

Fig.l IR spectra of a mixture of 89a and twice the molar amount of K2CO3 in Nujol mulls. I Pure 89a for reference II1 min after mixing III 10 min after mixing... 

Fig. 3 Monitoring for 40 min of the solvent-free benzoylation of 20 with 101b at 80 °C by IR spectral measurements in Nujol mulls...

Italic values of SO stretching frequencies are solution values. All others are for Nujol mulls. 

The sparingly water-soluble triethylammonium saltofBi2H122-is readily converted to the highly water-soluble sodium salt. A carefully weighed sample of the triethylammonium salt is treated with an exactly equivalent amount of standardized aqueous sodium hydroxide. The mixture is heated to effect solution and then boiled to expel the free triethylamine until the vapors are no longer basic. Evaporation to dryness then leaves a crystalline hydrate of Na2Bi2Hi2. The anhydrous salt is obtained by drying at 100°/1 n for 24 hours and has characteristic infrared absorption frequencies as a Nujol mull (exclusive of any frequencies coincident with Nujol) at 2470 (s), 1010 (w), 1070 (m), 770 (w), 727 (m),710 (m),and 700 (m) cm. 1... 

The situation with 7V-acyloxy-/V-alkoxyureas and carbamates is similar although infrared data were mostly determined by liquid film or condensed phase (KBr/nujol mull).52,131 However, the limited data for V-acyloxy-TV-alkoxyureas (Table 2, entries 69-72) give amide carbonyl frequencies ca. 1730 cm-1 that are raised by some 37-40 cm-1 by acyloxylation. Values for carbamates (Table 2, entries 73-77) are higher (mostly 1780 cm-1) but are raised to a lesser extent (10-20 cm-1) relative to their parent carbamates. Clearly, carbonyl vibrational frequencies will be influenced strongly by the adjacent amino or alkoxyl group in both analogues. 

The pharmaceutical industry comprises the largest segment, roughly 15 to 20%, of the infrared (IR) market. Modern mid-infrared instrumentation consists almost exclusively of Fourier transform (FT) instruments. Because of its ability to identify molecular species, FT-IR is routinely used as an identification assay for raw materials, intermediates, drug substances, and excipients. However, the traditional IR sample preparation techniques such as alkali halide disks, mulls, and thin films, are time-consuming and not always adequate for quantitative analysis. 

Sample beam aperture. This is where you put the holder containing your sample, be it mull or KBr pellet. You slip the holder into the aperture window for analysis. 

Phase. For KBr, say solid KBr. A Nujol mull is Nujol mull. Liquids are either solutions in solvents or neat liquids, that is, without any solvents, so call them liquids. 

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