Columnar cylindrical

Cilia are thin cylindrical hair-like structures with a cross-sectional radius of 0.1 gm projecting from the apical epithelial surface of ciliated columnar cells. Ciliary length is thought to correspond to periciliary fluid depth and range from approximately 7 gm in proximal airways to roughly 5 gm in more distal airways.- Each ciliated epithelial cell supports approximately 200 cilia at a density of eight cilia/gm. Short microvilli, possibly associated with secretory functions, are interspersed among the cilia. 

The other type of porous glass that has cylindrical pores is mesoporous silicate (MPS) (14,15). The advantage of MPS is in its feasibility to make a small pore diameter, typically below 10 nm. A columnar-phase liquid crystal, formed from surfactant molecules with a long alkyl chain tail and silicate molecules, is calcined to remove hydrocarbons. At the end, a hexagonal array of straight and uniform cylindrical holes is created in a crystalline order. MPS is not available commercially either. 

Figure 16.10 Conformational changes of polypropylene imine) dendrimers in LC materials from spherical to (a) cylindrical, in hexagonal columnar mesophase [130], and (b) ellipsoid, in smectic A mesophase [132]...

Columnar Term applying to somewhat cylindrical or prismatic crystals with a thickness of more than 500 microns in which the aspect ratio is generally low. 

Figure 5.4 Self-assembly of wedge-shaped molecules (modified from Zeng et al 2004). (a) Dendrons with fewer tethered chains adopt a flat slice-like shape (X is a weakly binding group), (b) The slices stack up and form cylindrical columns, which assemble on a two-dimensional hexagonal columnar (Col ) lattice (c). (d) Dendrons with more end-chains assume a conical shape, (e) The cones assemble into spheres, which pack on three different three-dimensional lattices (f) with different symmetries.

A cylindrical hard deposit, which is grown on the tip of a cathode (A in Fig. 10.2.2), consists of two regions an inner fibrous black core and an outer gray hard shell (15). The inner core had a columnar structure that was made up of bundles of nanotubes and flocks of polyhedral graphitic particles (32). On the other hand, the hard shell was made of stacked graphitic flakes. 

Percec et al. described the self-assembly of Rp-substituted bis-dendritic benzamides, such as compounds 179a and 179b, combining a dendron decorated with perfluorinated chains and a dendron with alkyl chains. In the hexagonal columnar LC phases of these molecules the smaller alkyl chains form the centers of the columns, the aromatics are arranged in cylindrical shells surrounding the aliphatic columns, while the larger fluorinated chains form a fluorous continuum... 

Figure 10.1 Schematic of two distinct pathways from the lamellar phase to the columnar inverted hexagonal i i phase of cationic liposome/DNA (CL/DNA) complexes. Along Pathway 1 the natural curvature C0=l/Ro of the cationic lipid monolayer is driven negative by the addition of the helper-lipid DOPE. This is shown schematically (middle top) where the cationic li DOT(4P is cylindrically shaped while DOPE is cone-like leading to the negative curvature. Along pathway II the to j transition is induced by the addition of a new class of helper-lipids consisting of mixtures...

Ewert KK, Evans HM, Zidovska A, Bouxsein NF, Ahmad A, Safinya CR (2006) A columnar phase of dendritic lipid-based cationic liposome-DNA complexes for gene delivery hexago-nally ordered cylindrical micelles embedded in a DNA honeycomb lattice. J Am Chem Soc 128 3998-4006... 

Fig. 12 Schematic representation of the self-assembly of dendromesogens into various type of mesophases (smectic, hexagonal and rectangular columnar, micellar cubic, and tetragonal phases) by the control of the molecular shape conformation (from flat tapered to cylindrical to conical and to spherical shape). From [126]...

Palisade layer A layer of palisade parenchyma (columnar or cylindrical cells rich in chloroplasts) in a leaf. 

A columnar mesophase has been used by the group of Percec for the creation of hydrogen-bonded supramolecular polymers.60-61 The phase separation of the apolar side groups of substituted benzamides with the core of the molecule accounts for the self-assembly into a cylindrical structure in which hydrogen bonding acting along the columnar axis occurs and stabilizes the column. 

Based on the weight loss during the PEC process measured using the microbalance, the porosity is estimated to be 0.1. Because the columnar pores are generally uniform throughout the porous layer, it is reasonable to assume that the columnar porous structure we obtain is comparable with a perfect hexagonal packed cylindrical pore lattice. For such a pore lattice, the porosity P can be calculated using ... 

Porous anodic alumina attracts an attention of a scientific community due to an ordering nanostmcture resulting from self-regulated electrochemical anodic process. Aluminum is a unique material, which forms a regular porous oxide, composed of a packed array of columnar hexagonal cells, each having a cylindrical pore in the center [1], The cell size is known to be determined by the electrolyte and anodization regimes [1,2]. We have found that the cell size can be also tuned by Ti in Al-Ti alloys. The results obtained are presented in this paper. 

Considerations of Maxwell-Gamett [273, 274] and Bragg and Pippard [275] based on Lorentz-Lorenz polarization theory have been put into the form for dielectric films composed of cylindrical columnar crystals by Harris, Macleod et al. [276] ... 

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