Drying procedure

Yarn drying procedures are far more critical than staple drying procedures. AH ceUulosic fibers expand when wetted and contract on drying, the... 

The accuracy of VPD-TXRF depends largely on the reliability of the reference material (cf Sect. 4.1.1.3) and on the reproducibility of the droplet drying procedure (Fig. 4.17) [4.75, 4.76]. Mass absorption sets the upper limit of reliable analyses to lO atoms cm [4.77]. 

Without special drying procedures and completely inert handling, water is omnipresent in ionic liquids. Even the apparently hydrophobic ionic liquid [BMIM][(CF3S02)2N] saturates with about 1.4 mass% of water [15], a significant molar amount. For more hydrophilic ionic liquids, water uptake from air can be much greater. Imidazolium halide salts in particular are laiown to be extremely hygroscopic, one of the reasons why it is so difficult to make completely proton-free chloroaluminate ionic liquids. 

The factors chosen were variations in vessel size, the effect of non-aseptic operation and medium recycle, and variations in recovery and drying procedures. 

The method will now be tested in a ringtest by 8 dfferent laboratories in Europe. A preliminary range finding will be done in Vienna in October 1999. Test oganisms will be Stapylococus aureus and Pseudomonas aeruginosa, exposure time will be 5 minutes. The test surfaces will be stainless steel disks (2 cm diameter) with a specific finish. The problem of a standardized drying procedure was discussed. There was no decision about the number of replicates of the test. 

THF is distilled from benzophenone ketyl and stored over sodium wire under a nitrogen atmosphere. For the drying procedure and caution, see Org. Synth., Coll. Vol. VI11990, 451 and Org. Synth., Coll. Vot. V1973, 976 respectively. 

Fig. 10 The FT-Raman spectra over the wavenumber range 10-250cm-1 ofmagnesium stearate after different drying procedures. Top, heated at 90°C to constant weight under vacuum middle, heated to 60°C to constant weight under vacuum bottom, commercially supplied sample.

The intrinsic dissolution rates of pharmaceutical solids may be calculated from the dissolution rate and wetted surface area using Eq. (36) or (37). For powdered solids, two common methods are available the powder intrinsic dissolution rate method, and the disc intrinsic dissolution rate method. In the former method, the initial dissolution rate of one gram of powder is determined by a batch-type procedure as illustrated in Fig. 13A. The initial wetted surface area of one gram of powder is assumed to equal the specific surface area determined by an established dry procedure, such as monolayer gas adsorption by the Brunauer, Emmett, and Teller (BET) procedure [110]. 

Oxidative catalysis over metal oxides yields mainly HC1 and C02. Catalysts such as V203 and Cr203 have been used with some success.49 50 In recent years, nanoscale MgO and CaO prepared by a modified aerogel/hypercritical drying procedure (abbreviated as AP-CaO) and AP-MgO, were found to be superior to conventionally prepared (henceforth denoted as CP) CP-CaO, CP-MgO, and commercial CaO/MgO catalysts for the dehydrochlorination of several toxic chlorinated substances.51 52 The interaction of 1-chlorobutane with nanocrystalline MgO at 200 to 350°C results in both stoichiometric and catalytic dehydrochlorination of 1-chlorobutane to isomers of butene and simultaneous topochemical conversion of MgO to MgCl2.53-55 The crystallite sizes in these nanoscale materials are of the order of nanometers ( 4 nm). These oxides are efficient due to the presence of high concentration of low coordinated sites, structural defects on their surface, and high-specific-surface area. 

Both hand washing and machine washing and drying procedures are in use in industrial analytical laboratories. The variety of available soaps include alkaline phosphate-based and phosphate-free soaps. While phosphate-based soaps are quite satisfactory for cleaning purposes because phosphate helps to... 

Figure 14.17 Relationship between notched impact strength of PET compounds and their moisture content. The plot emphasizes the need for proper drying of PET resin to reduce the moisture content to below 200 ppm before melt processing. Intensive drying procedures are time-consuming and costly and therefore internal desiccants are often used...

Thermal Stability. Lithium-ion batteries can be poisoned by water, and so materials going into the cell are typically dried at 80 °C under vacuum. Under these conditions, the separator must not shrink significantly and definitely must not wrinkle. Each battery manufacturer has specific drying procedures. The requirement of less than 5% shrinkage after 60 min at 90 °C (in a vacuum) in both MD and TD direction is a reasonable generalization. 

Fig. 28. Weight loss of epoxies prepared with 20 wt % cyclohexane before and after the drying procedure measured with TGA...

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