Waxes, types

Along each of these isotherms solid and liquid are in equilibrium each corresponds to a melting-point under a given pressure. Thus we see (qualitatively) that the melting-point of a substance of the wax-type is raised by increasing the pressure that of a substance of tlie ice-type is, on the other hand, lowered. 

Bunsen (1850), Hopkins (1854), Batelli (1887), and de Yissier (1892) also made experiments on the effect of pressure on the melting-point of bodies of the wax-type. The latter found for acetic acid ... 

The melting-point (T,p) curve (unlike a vapour-pressure curve of a liquid) does not end abruptly at a critical point (Ar = 0, L = 0) it is an endless curve, probably forming a closed loop ABCD, unless it intersects some other curve or the axes of co-ordinates. At high pressures it bends round towards the p axis, and according to Tammann, takes the shape indicated by the following considerations. It is known from experiment that (for substances of the wax-type) the melting-point increases with rise of pressure,... 

Continuous transition of state is possible only between isotropic states it may thus occur between amorphous glass (i.e., supercooled liquid of great viscosity) and liquid ( sealing-wax type of fusion ), or between liquid and vapour, but probably never between anisotropic forms, or between these and isotropic states. This conclusion, derived from purely thermodynamic considerations, is also supported by molecular theory. 

When vinyl is chosen for laboratory floor use, the heavier commercial grade is recommended over the thinner material often used in homes. The cushioned type, while easier to walk on, does not have sufficient ability to withstand laboratory wear and tear. Neither does the no-wax type. Good maintenance should include regular waxing, which will greatly increase the ability of any flooring to resist damage from wear and from chemical spills. 

Metals Metals are used as collapsible tubes and in aerosol containers. The most common metals in use are tin, aluminum, and lead. Tin is the most expensive, while lead is the cheapest. Laminates of tin-coated lead provide the appearance and oxidation resistance of straight tin at lower prices [89]. Tin is the most chemically inert of all collapsible tube metals. It offers a good appearance and compatibility with a wide range of products. Aluminum tubes provide the attractiveness of tin at relatively lower cost. Lead has the lowest cost of all tube metals and is widely used for nonfood products such as adhesives. However, with internal linings, lead tubes are used for such products as fluoride toothpaste. If the product is not compatible with bare metal, the interior can be flushed with wax-type formulations or with resin solutions. 

The inclusion of wax-type phlegmatizing substances in the mixture facilitates the pressing of the explosive as it decreases the friction between the crystals. Thus a mixture with a higher density can be obtained by applying a lower pressure. 

Lammerhofer and Lindner reported on the enantiomer separation of derivatized amino acids and profens on a weak-anion-exchange(WAX)-type stationary phase based on chiral quinine carbamate selectors by p-CEC [54,55]. The separations were performed either under aqueous or [54] non-aqueous conditions [55]. The efficiency obtained in the p-CEC mode was about two to three time higher than with LC using an acetonitrile/buffer flow system [54], Very high resolutions and efficiencies were found for non-aqueous p-CEC. For example, the enantiomer separation of Fmoc-leucine was achieved in less than 10 min with a resolution Rs of 6.9 at about 100 000... 

Fig. 9.12. Enantiomer separation of Fmoc-Leu on a quinine carbamate-based WAX-type CSPs by CEC under a slight overpressure (8 bar). Conditions capillary, 100 pm I.D. x 25 cm (overall length, 33.5 cm) acetonitrile-methanol (80 20, v/v) 200 mM acetic acid, 10 mM triethylamine -25 kV UVdetection, 254 nm. Reproduced from [58], with permission.

In particular, as far as the plastic catalytic degradation is concerned, there are various possible scenarios. In large urban areas the best approach probably is to build a plastic waste pyrolysis plant in an acceptable near area at not to great distance, in order to minimize transport cost of the plastic waste. In that case, safety and environmental concerns of such a new plant should first be denied with satisfactorily before the new plant can get the go-ahead. Near refineries however, the best approach might be to co-feed plastic waste with oil fractions into refinery crackers, or even have a unit of pure thermal pyrolysis first with the produced wax-type fraction to be upstaged in another reactive refinery process. In the first case of co-feeding, a lot of research has to be carried out, addressing aspects of defluidization mainly, before an alteration of a process of the scale of FCC units can go ahead. 

The TEXTILE WAX types are finishing agents which impart smoothness and lustre to the fabric. 

CNC ARIDRY AA is a wax-type aluminum water repellent which is used as an excellent all-purpose repellent for synthetics. The product is also a napping aid for nylon and/or orlon fleece fabrics. 

Is a 20% dihydroxy-dichloro-diphenyl methane. This emulsion type product is cationic in nature and is compatible with alum-inum/wax type water repellent material. This permits the single bath application of a water repellent and a mildew-proofing agent. EPA 6009-8... 

Wax type water repellent for use on all fabrics resin bath compatible. 

Fig. 9.36. Enantioscparation of a-aryl propionic acids on 1-allyl-tcrguride-ba.scd WAX type CSP (a) fenoprofen. (b) flobufen. (c) naproxen, and (d) ketoprofen. Exp. cond., 20 mM potassium acetate (pH 3.6)-ttcetonitrile (50 50, v/v( How rate. I.O ml/min detectum. 255 nm (reprinted with permission from Ref. 1.3971).

ENANTIOSEPARATION OF PHARMACELTICALLY RELEVANT CHIRAL COMPOUNDS USING WEAK ANION EXCHANGE (WAX) TYPE CSPs... 

Another popular depilatory is the wax-type product. This depilatory is applied as a viscous liquid over the hair area to be removed. It is often warmed under the tap prior to application and applied in the direction of hair growth. The wax is sometimes covered with a paper cloth, oftentimes supplied with the product. The cloth adheres to the sticky wax composition on the skin and is pulled in the direction against the hair growth removing much of the sticky wax and the hair. This procedure is repeated until the desired area is depilated. The residual wax is then washed and peeled from the skin. 

A wide range of calcium-containing PE waxes with different acidity index values and calcitxm contents have been obtained by the proper choice of the OXPE wax type, i.e. the oxidation degree, and the proportion of the added Ca(0H)2 ... 

Out of doors the varnish (wax type) has good gloss retention, but tends to fail by cracking, especially on expanding and contracting substrates. The pigmented types are usually based on allyloxy polyesters and they lose gloss rather quickly. 

Animal skin surface lipids have two types of diester waxes. In the first, a hydroxy acid has its hydroxyl group esterified to a normal fatty acid and its carboxyl group to a fatty alcohol. The second wax type consists of an alkane qj, /8-diol in which both hydroxyls are esterified with fatty acids (Nicolaides et al., 1970). 

Conventional Wax-type column with the phase coated onto the surface of the fused silica — no anchoring. 

FIGURE 3.44 Comparison of cross section of a SOLGEL-WAX Column with a conventional wax-type column. (Reproduced with permission of SGE International Pty.)... 

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