Ribbon construction

The addition of carboxymethyl cellulose (CMC) and methyl cellulose (MC) to the nutrient solution (0.5-2.0 m/v %) effects a change of the fiber and network architecture [38] (Fig. 7). In the first case, the crystallization of the BC is affected by agglomeration of the CMC onto the fibers during self-assembly. The additive seems to compete with the BC for hydrogen-binding sites during ribbon construction [39] (Fig. 7a). In the second case, the adsorption takes place mainly on the planar ribbons (Fig. 7c). 

Part of the host framework in [(CH3 )4N]+[H2NC0NHC02] - -5(NH2)2CO showing the double ribbon constructed by allophanate anions and one of the independent urea molecules. From T. C. 

The basic component of the host lattice of 1.1 may also be described as a composite ribbon constructed from urea molecules C(l)-C(6) and (H20 F )2 units (Figure 9). These composite ribbons point alternately in the [110] and [TlO] directions, and their cross-linkage by C(7), F(2), 0(2W), and 0(3W) generates the channel-type host network. 

Figure 34. Hydrogen-bonded layer in 2(C2Hs)4N HC02-2(NH2)2CS HC02H (2.11) formed by ribbons constructed from thiourea dimers and protonated formate trimers. Broken lines represent hydrogen bonds.

HNEt3NH] [(V0)3(0H)2(P04)2] Layered Ribbons constructed from binuclear units of face sharing VOe octahedra linked by corner sharing into infinite chains. Each binuclear unit corner-shares to a VO5 square pyramid 12.048(2) 6.3470(10) 20.249(4) P = 105.30(3) P2i/n 224... 

An exception to this common trend is the ID phase [(V0)(P04) (H2NCH2CH2NH3)] (168), shown in Figure 39. The structure consists of ID ribbons constructed from V(IV) octahedra and PO tetrahedra. The coordination about the vanadium centers is defined by a terminal 0x0 group, four... 

The use of a ribbon construction for the feeder flight significantly reduces the run of shaft exposed to the formation of cracks therefore, in sensitive cases this may be considered as a constructional method, other factors being compatible. 

The reaction of ciprofloxacin (cfH) with metal salts in the presence of aromatic polycarboxylate ligands (or under basic conditions) has been found to give original metal-cfH complexes, for example, [Ba2(cf)2(l,4-bdc)(H20)2] H20 and [Mn(cfH) (1,3-bdc)] (bdc=benzenedicarboxylate). The structure of [Ba2(cf)2(l,4-bdc)(H20)2]-H2O consists of unique two-dimensional arm-shaped layers (Fig. 6), while the second complex contains double-chain-Uke ribbons constructed from [Mn2(cfH)2(C02)2] dimers and 1,3-bdc (Fig. 7) [369],... 

Flame plasma systems are manufactured with two primary burner configurations - ribbon and drilled port. Ribbon burners are typically constructed with a cast iron body and with stainless steel ribbons that are meshed (or opposed to each other) to construct varying pilot and main flame patterns. As the open area of the ribbon construction increases, so does the capacity of the ribbon burner. Drilled... 

FIGURE 6,37 Ribbon structures of several protein modules utilized in the construction of... 

Flame Arrestors and Explosion Reliefs. The flame trap is constructed of strips of corrugated and flat steel ribbon wound in a spiral. It breaks up a flame in the very small passages between the corrugations where the flame is quenched and extinguished. 

The screw configuration is normally either a ribbon-type helical screw or a series of paddles mounted on a common shaft. Materials of construction are selected based on the specific application and materials to be mixed. Typically, the screws are either steel or stainless steel, but other materials are available. 

As the general standard of protective coatings has improved (materials, application and construction standards) the use of sacrificial anodes has extended to soil of ca. 10 000 ohm cm or more for buried pipelines. By using anodes in extruded ribbon form and placing them as close as possible to the structure to be protected they can be used in soils of high resistivity. 

For the batch mixing of viscous pastes and doughs using ribbon impellers and Z-blade mixers, the tanks may be mounted horizontally. In such units, the working volume of pastes and doughs is often relatively small, and the mixing blades are massive in construction. 

For technological applications it is highly desirable to be able to design self-assembling systems to have particular physico-chemical properties under a given set of experimental conditions. Using computer simulation, it is possible to construct an atomistic model of tapes, ribbons and fibrils to study all of the interatomic interactions within the system in a quantitative manner. Figure 13 shows atomistic... 

Pulse-mode pyrolyzers include resistively-heated electrical filaments or ribbons and radio frequency induction-heated wires [841,842,846,848,849]. The filament or ribbon-type pyrolyzers are simple to construct. Figure 8.45, and typically consist of an inert wire or ribbon (Pt or Pt-Rh alloy) connected to a high-current power supply. Samples soluble in a volatile solvent are applied to the fileutent as a thin film. Insoluble materials are placed in a crucible or quartz tube, heated by a basket-lilce shaped or helical wound filiunent. The coated filament is contained within a low dead volume chamber through which the carrier gas flows, sweeping the pyrolysis products onto the column. The surface temperatui of the filament is raised rapidly from ambient temperature to He equilibrium pyrolysis temperature. This... 

In supramolecular chemistry [31] iterative synthesis is frequently used for the construction of ribbon and belt shaped molecules [32]. The repeated Diels-Alder reaction is suitable for the preparation of beltenes, collarenes and cycla-cenes containing partially or fully unsaturated annelated six-membered rings. They are potential molecular receptors for appropriate substrates. Stoddart et al. synthesized the cyclacene 18 by Diels-Alder cyclization of the bisdiene 15 and the bisdienophil 16 [33] (Fig. 10). 

A different iterative method for the construction of ribbon and belt type molecules using tetrafunctionalized arenes and cyclophane monomers was developed by us [42]. The newly designed key compound 23 allows a repeated elongation of a ribbon type molecule by two benzene units (Fig. 12) [43]. 

Fig. 12. Successive construction of molecular ribbons according to Vogtle et al.

Fig. 3. (A) Ribbon diagram of ribosomal L9 protein from B. stearothermophilus. The N- and C-terminal domains are labelled. The C-terminal construct consisting of residues 58-149 is shaded. (B) Ribbon diagram of the C-terminal domain showing the location of the three histidine residues. Reprinted from J. Mol. Biol., Vol. 318, S. Sato and D. P. Raleigh, pH-dependent stability and folding kinetics of a protein with an unusual alpha-beta topology The C-terminal domain of the ribosomal protein L9 , pp. 571-582, Copyright 2002, with permission from Elsevier Science.

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