Crystal scale

Concept used in sophisticated scaling models, whereby certain ions in aqueous solution are said to associate in pairs (e.g., CaS04, CaHC03-). These ion pairs are then deducted from the total analytical value, to provide an estimate of the free ion content available for seed crystal scaling or growth agglomeration and deposition. 

Ciprofloxacin White crystalline precipitates lid margin crusting crystals/scales foreign body sensation itching conjunctival hyperemia bad taste in mouth corneal staining keratopathy/keratitis allergic reactions lid edema tearing photophobia corneal infiltrates nausea decreased vision. 

The anhydrous salt forms yellow crystal scales deliquesces density 3.55 g/cm3 melts at 1,001°C suhhmes at 973°C highly soluble in water, 64 g/lOOmL at 20°C soluble in alcohol. 

Figure 1. Scanning Electron Micrograph of Large AlP0 -5 Crystals (scale bar 10 /zm).

Figure 2. Mixture of unreacted kaolinite and of spheroids (high index faces exposed) of zeolite omega obtained in the first stages of the crystallization. Scale bar 5 urn.

Figure 5. Scanning electron micrographs of zeolites cocrystallizing with ECR-1 (a) mordenite barrel like agglomerates (b) pure samples of different mazzites showing similar morphology to ECR-1 but having a smaller aspect ratio and much shorter crystals. Scale markers are 1. (LHS) and 10M- (RHS). ...

Benzoic Acid occurs as white crystals, scales, or needles. It begins to sublime at about 100° and is volatile with steam. One gram is soluble in 275 mL of water at 25°, in 20 mL of boiling water, in 3 mL of alcohol, in 5 mL of chloroform, and in 3 mL of ether. It is soluble in fixed and in volatile oils and is sparingly soluble in hexane. 

Fig. 29. Crystallizer scale-up factors. After Newman and Bennett (N3).

Properties Fine, white, crystal scales odorless tasteless. Mp 187-188C. Soluble in alcohol, ether, and hot water insoluble in light hydrocarbon solvents decomposed by strong alkalies. 

In addition, scale-up of a nucleation-dominated process is difficult to predict, unless the generation of supersaturation is well controlled. The difficulties associated with stirred-batch crystallization scale-up relying on nucleation were highlighted by Nyvlt (1971, p. Ill) ... 

The requirements for particle off-bottom suspension are also discussed in many literature references including Zwieterling (1958), Chowdhury et al. (1995), and Paul et al. (2003, Chapter 10). Methods of calculating various degrees of homogeneity in solids are presented. These calculations are an important part of crystallization scale-up studies. 

White, odorless crystals, scales or powder becomes pinkish on long exposure to light. One gram dissolves in 0.9 ml water, 9.2 ml alcohol, 4 ml glycerol. The aq soln is slightly acid. pH 5-6. A satd aq soln contains 20.06% w/w at — 1.5°. See Sidgwick, Ewbank, J. Chem- Soc. 121, 1847, 1850 (1922). Proton from light. LDg, i.p. in rats 780... 

In a zeolite catalyst diffusional limitations may occur at either the particle scale or the crystal scale. In the latter case the basic analysis remains the same, but since the rate constant is defined with respect to the concentration of reactant in the vapor phase while the intracrystalline diffusivity is defined with respect to the adsorbed phase concentration, the Thiele modulus must be redefined to introduce the dimensionless adsorption equUibriimi constant (K) ... 

FIGURE 2 A representative photograph of a gold sample after dissolution of the latex. The highly ordered, lace-hke gold structure is an analogue of a 3D wire-mesh photonic crystal scaled down to the sub-micrometer region. SOURCE Adapted from Velev et al. (1999). Reprinted with permission from Nature. 

Fig. 5 Cross sectional (a) BF and HAADF (b) stem imaging of a bilayer graphene-BN superlattice revealing the high quality material that may be produced by stacking of 2D crystals. Scale bars are 2 nm. Reproduced from S. J. Haigh, A. Gholinia, R. Jalil, S. Romani, L. Britnell, D. C. Elias, K. S. Novoselov, L, A. Ponomarenko, A. K. Geim and R. Gorbachev, Nat. Mater., 2012. 11, 764. ...

Colorless to white crystal scales or crystalline powder, m.p. 270 °C (decomposition) (18). When measured in static air, it decomposes exothermically after melting, products K2CO, and carbon [19]. 

It was found during the trials that the stainless steel disc was subject to crystal scaling after a few runs. However, a thin layer of PTFE suppressed this without significantly impairing the disc s heat transfer performance. (For the reader interested in... 

Fig. 7. Scanning electron microscopy images of L glutamic acid crystals (scale bar=200pm) (A) crystal morphology of crystals grown on the surface of L-AAPP SAMs and (B) crystal morphology of crystals grown from solution. (Dressier and Mastai, 2007)...

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