Topping powders

Figure 3. XRD patterns for the iron substituted composition having the empirical formula of Bi 2-2x) 2x 030i2 where x = 0.40. The top powder diffraction pattern is for the aerosol prepared material as directly obtained from the reactor. The bottom diffraction pattern is for the material after calcining in air for 4 hr at 450°C.

Staff "Top Powder Metallurgy Parts Honored, Advanced Materials and Processes, 8 (August 1991). 

Figure 3 Per cent soiids of topping powders and corresponding dry mixtures measured by pNMR at temperatures from 5°C to 25°C. Reprinted from reference 12, courtesy of the American Oii Chemists Society.

Crystallization of supercooled fat in topping powders may be studied by NMR afterreconstitution in heavy water. Below room temperature spontaneous fat crystallization takes place under isothermal conditions in the presence of effective emulsifier (PGMS) but not with ineffective emulsifiers or without emulsifiers (Figure 4). 

The time scale of fat crystallization is much shorter for topping powders than for ice cream mix as presented in Figure 2. This is due to the much higher emulsifier content in topping powder. The induction of fat crystallization in whippable emulsion systems is due to interfacial protein desorption from the fat globules of the emulsion mediated by the emulsifiers. This phenomenon is described in section 3.1. 

Figure 6 a. Structure of topping powder in the dry state with close-packed globular fat particles (f) (diameter less than 0.5 ftra). b. Crystallization and transformation of the globular structure of fat particles into thin layers of crystal platelets (c). Reprinted from reference 21, courtesy of Verlag Th. Mann. 

The viscosity range varies, depending on the whippable emulsion system in question. In whipped toppings viscosity increases as soon as the topping powder is reconstituted in cold water. This is due to the formation and aggregation of hydrated fat crystals which will... 

Bern, M.B., Topping powder, internal Grindsted report (1992). 

Powders generally pack rather densely, particularly in comparison to small-size substrate, and the interaction of luminous gas (for deposition) with powder surface is limited to more or less the top powder layer. Consequently, the mixing by tumbling action is important to treat powder uniformly. The mixing along the axis of tube is also an important factor. If dilferent color powders are placed in different... 

Fig. 2. Simulated X-band EPR spectra for a nitroxide powder pattern. Top Powder patterns for each hyperfine line and the relationship to the principal tensor values from the spin Hamiltonian. Middle Absorption pattern. Bottom First-derivative pattern as is usually seen in a continuous wave EPR spectrum.

Fig. 10.7 (Top) Powder XRD spectra of discharge product of the composite cathode (Super P/ Kynar) cycled in 1.0 M LiPF6-TEGDME cell (left) and the composite cathode (Super P/PTFE) in either 1.0 M LiPFs-l.S-dioxolane or 2-methyltetrahydrofuran (2-Me-THF) (right). (Bottom) FTIR spectra of the corresponding composite cathode (Super P/Kynar) cycled in 1.0 M LiPF6/TEGDME cell (left), and the composite cathode (Super P/PTFE) in either 1.0 M LiPF -l,3-dioxolane or 2-methyltetrahydrofuran (2-Me-THF) (right). Reproduced with permission [52]...

Figure 18 Calculated (bottom) and simulated (top) powder diffractograms of 5-bromo-2-(hydroxymethyl)pyridine. ...

Chem. Descrip. Propylene glycol esters of fatty acids Uses Alpha-ending emulsifier in toppings, powdered cake improvers, cake mixes, alpha-crystalline stabilizer for sponge cake foaming gel Reguiatory E477... 

Chem. Descrip. Propylene glycol ester of fatty acids Uses Alpha-ending emulsifier in toppings, powdered cake improvers, cake mixes, alpha-crystalline stabilizer for sponge cake foaming gel Properties Waxy block m.p. 30-36 HLB 3.7 (caluculated) acid value 3 max. iodine value 3 max. sapon. value 173-183 hydroxyl value 170-190 PPE156 [Lakeland Labs Ltd]... 

Figure C2.17.8. Powder x-ray diffraction (PXRD) from amoriDhous and nanocry stalline Ti02 nanocrystals. Powder x-ray diffraction is an important test for nanocrystal quality. In the top panel, nanoparticles of titania provide no crystalline reflections. These samples, while showing some evidence of crystallinity in TEM, have a major amoriDhous component. A similar reaction, perfonned with a crystallizing agent at high temperature, provides well defined reflections which allow the anatase phase to be clearly identified.

Stopper the side arm of a 25 or 50 ml. distilling flask and fit a vertical water condenser into the neck. Place 0-5-1 -0 g. of the dry acid (finely powdered if it is a solid) into the flask, add 2-5-5 0 ml. of redistilled thionyl chloride and reflux gently for 30 minutes it is advisable to place a plug of cotton wool in the top of the condenser to exclude moisture. Rearrange the condenser and distil off the excess of thionyl chloride t (b.p. 78°). The residue in the flask consists of the acid chloride and can be converted into any of the derivatives given below. 

Place 1 0 g. of the monobasic acid and 2 g. of aniline or p-toluidine in a dry test-tube, attach a short air condenser and heat the mixture in an oil bath at 140-160° for 2 hours do not reflux too vigorously an acid that boils below this temperature range and only allow steam to escape from the top of the condenser. For a sodium salt, use the proportions of 1 g. of salt to 1 5 g. of the base. If the acid is dibasic, employ double the quantity of amine and a reaction temperature of 180-200° incidentally, the procedure is recommended for dibasic acids since the latter frequently give anhydrides with thionyl chloride. Powder the cold reaction mixture, triturate it with 20-30 ml. of 10 per cent, hydrochloric acid, and recrystallise from dilute alcohol. 

Method 1 (with acetyl chloride). Equip a dry 500 ml. round-bottomed or bolt-head flask with a reflux condenser, and fit the top of the condenser with a two hole cork, one opening for a separatory funnel and the other for a delivery tube connected to an inverted funnel which dips just below the surface of about 200 ml. of water in a beaker (compare Fig. II, 13, 8). Place 40 g. of anhydrous, finely-powdered aluminium chloride (see Section IV,2) and 88 g. (100 ml.) of dry A.R. benzene in the flask and cool the latter in a bath of cold water (not ice water since benzene may crystallise). Through the separatory funnel at the top of the condenser add 29 g. (27 ml.) of redistilled acetyl chloride slowly during half an hour and shake the flask frequently to ensure thorough mixing of the... 

Preparation of benzyl cyanide. Place 100 g. of powdered, technical sodium cyanide (97-98 per cent. NaCN) (CAUTION) and 90 ml. of water in a 1 litre round-bottomed flask provided with a reflux condenser. Warm on a water bath until the sodium cyanide dissolves. Add, by means of a separatory funnel fitted into the top of the condenser with a grooved cork, a solution of 200 g. (181-5 ml.) of benzyl chloride (Section IV.22) in 200 g. of rectified spirit during 30-45 minutes. Heat the mixture in a water bath for 4 hours, cool, and filter off the precipitated sodium chloride with suction wash with a little alcohol. Distil off as much as possible of the alcohol on a water bath (wrap the flask in a cloth) (Fig. II, 13, 3). Cool the residual liquid, filter if necessary, and separate the layer of crude benzyl cyanide. (Sometimes it is advantageous to extract the nitrile with ether or benzene.) Dry over a little anhydrous magnesium sulphate, and distil under diminished pressure from a Claisen flask, preferably with a fractionating side arm (Figs. II, 24, 2-5). Collect the benzyl cyanide at 102-103°/10 mm. The yield is 160 g. 

The fluid plasticizer (solvent) consists of an energetic compound, eg, nitroglycerin, an inert carrier, and a stabilizer. The system is evacuated to remove volatiles, moisture, and air, and the plasticizer is then pressurized and passed slowly upward through the powder bed while the powder is held stationary by a pressure plate on the powder column. Casting solvent may also be added from the top of the mold. 

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