Other modifications

The other C, A modification is a disordered, poorly crystalline form, called proto-C,A, which was obtained metastably from simulated clinker liquids, either by rapid cooling or by static crystallization at low temperatures (BIO). It gave an XRD powder pattern with broadened peaks, corresponding to the systematically strong reflections of cubic CjA indexable on the subcell with a 0.39nm. Analytical electron microscopy of individual crystals showed it to be very high in substituents, one preparation, for example, having an Fe/Al ratio of 0.54 (H6). 

The HA hydrogel can be chemically modified in many different ways in order to achieve a better ECM-like component and architecture, to promote its interaction with cells. PLL is usually used as a coating substrate on the surface for cell adhesion when being cultured in vitro. It can be taken into the gel for the modulation of neuronal cell adhesion and neural network formation. The report by Tian and co-workers [20] has shown that this modified hydrogel has good compatibility with the cells and surrounding tissue in the brain. 

An ECM protein, laminin, which participates in neuronal development and survival, can be immobilised on the backbone of the HA hydrogel, and this has been proven by Hou and co-workers [21]. In this case, the gel still possesses the mechanical properties and rheological behaviour similar to brain tissue. After being implanted into a cortical lesion it promotes neurite extension and angiogenesis into the porous scaffold, and simultaneously inhibits glial scar formation. 

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Other modifications have special but more limited apphcations. A centrifugal bowl may contain, instead of disks, several aimular baffles that take the hquid through a labyrinth path before discharge. The multiple cylinders increase cake capacity to as much as 70 L for easily sedimented sohds. This centrifuge is used for clarification of food symps and antibiotics (qv), and for recovery of heavy metallic salts and catalysts (see Fig. 14c). 

Starch oxidation was investigated as early as 1829 by Liebig. The objective, as with other modifications, was to obtain a modified granular starch. The oxidant commonly employed is sodium hypochlorite, prepared from chlorine and aqueous sodium hydroxide. This reaction is exothermic and external cooling must be provided during preparation of the oxidant. 

Other modifications of acid wool dyes have groups which react by nucleophilic substitution of basic groups ia proteia fibers (NH2 groups, etc). The iatroduction of Procion dyes by ICI ia 1956 was the most important development ia the field of technological azo dye chemistry. Chemically, many of the reactive dyes are prepared from the group of the anionic monoazo dyes (see Dyes, reactive). 

Other modifications of the polyamines include limited addition of alkylene oxide to yield the corresponding hydroxyalkyl derivatives (225) and cyanoethylation of DETA or TETA, usuaHy by reaction with acrylonitrile [107-13-1/, to give derivatives providing longer pot Hfe and better wetting of glass (226). Also included are ketimines, made by the reaction of EDA with acetone for example. These derivatives can also be hydrogenated, as in the case of the equimolar adducts of DETA and methyl isobutyl ketone [108-10-1] or methyl isoamyl ketone [110-12-3] (221 or used as is to provide moisture cure performance. Mannich bases prepared from a phenol, formaldehyde and a polyamine are also used, such as the hardener prepared from cresol, DETA, and formaldehyde (228). Other modifications of polyamines for use as epoxy hardeners include reaction with aldehydes (229), epoxidized fatty nitriles (230), aromatic monoisocyanates (231), or propylene sulfide [1072-43-1] (232). 

Butyl rubber and other isobutylene polymers of technological importance iaclude various homopolymers and isobutylene copolymers containing unsaturation achieved by copolymerization with isoprene. Bromination or chlorination of the unsaturated site is practiced commercially, and other modifications are beiag iavestigated. 

Flue Gas Recirculation Flue gas recirculation, alone or in combination with other modifications, can significantly reduce thermal NO. Recirculated flue gas is a diluent that reduces flame temperatures. External and internal recirculation paths have been applied internal... 

This sample, referred to in Chapter 2, can serve as a guide for planning and conducting assessments of tollers. It may require additions, revisions, or other modifications in order to meet the needs of facility specific assessment objectives, the facility setting, or other special circumstances. This sample includes ... 

Concluding this section, two interesting variants of the STM should be addressed. The spin-polarized STM (SPSTM), which works with a ferromagnetic tip, can be used to probe surface magnetism with high resolution [5.47, 5.48]. Other modifications of the STM involve electromagnetic radiation, whereby two basic concepts can... 

However, these modifications of the previously derived expressions are not significant for v p < 1/4. Ekvall made other modifications to account for such features as square or rectangular versus round fibers and for stress concentrations due to fibers [3-3]. 

Three other modifications of the standard conditions provide synthetically useful strategies for the preparation of dihydrofurans. One method, called the interrupted Feist-Benary reaction, utilizes milder reaction conditions to stop the final dehydration step. For example, Calter combined bromide 47 with dicarbonyl 48 to produce dihydrofuran 49 as a mixture of diastereomers. He examined the scope and diastereoselectivity of this process and applied this reaction toward the synthesis of the polycyclic core of the zaragozic acids. A method principally designed to yield practical syntheses of cyclic ketodiesters also furnished a dihydrofuran via a variation of the interrupted Feist-Benary reaction. ... 

The above sterilized medium was inoculated with 11 liters of seed inoculum having a bacterial count of approximately 20 billion per cc. The tank was fermented at 37°C without pH adjustment, aeration, or other modification for 14 hours at the end of which time 320 cc of 50% dextrose was added. After this the pH was adjusted to 7.0 at 15 minute intervals with 5.0 N sodium hydroxide. The volume of sodium hydroxide required for neutralization was noted and 115% of this volume of 50% dextrose solution added after each pH adjustment. At the end of about 8 hours the bacterial count had ceased to increase and the fermentation was terminated. At this time the fermentation medium contained approximately 1,000 units of streptokinase per cc. 

Other modifications which restrict ring cleavage are die formation of 6p,19-oxido derivatives and 3a, 5a cydo-derivatives. The structures of some of these are given in Figure 9.4. 

The Ml test equipment is easy to operate, provides repeatable results, and low cost to operate. It is widely used for quality control and for distinguishing between members of a single family of plastics. Specifically, this MI makes a single-point test that provides information on resistance to flow at only a single shear rate. Because variations in branching or MWD can alter the shape of the viscosity curve, the MI may give a false ranking of plastics in terms of their shear rate resistance to flow. To overcome this problem, extrusion rates are sometimes measured for two loads, or other modifications are made. 

The exact role of individual histone acetylations will have to be determined in the context of other modifications and the number of lysine residues effected. However, the general importance of histone acetylation as a regulator for chromatin activity is undisputed. This leads to the intriguing possibility to develop drugs that target histone acetylation for therapeutic purposes. The primary targets for drug development are the histone acetyl transferases (HATs) and the histone deacetylases (HDACs) which introduce and remove histone acetylations [2, 3]. 

From the more recent reports cited below, further references to the extensive literature concerned with calcite decomposition may be traced. Other modifications of CaC03 (aragonite and vaterite) undergo solid phase transitions to calcite at temperatures of 728 K and 623—673 K respectively [733], below those of onset of decomposition (>900 K). There is strong evidence [742] that the reaction... 

Since a great number of such transformations were described in the chemical literature, only selected examples of general importance will be presented here. This section will consist of the following parts reactions of the sulphoxide a-carbanions introduction, substitution, transformation and elimination of heteroatomic groups attached to organic substituents in sulphoxides additions to unsaturated sulphoxides other modifications of organic substituents in sulphoxides. 

The structural principles of Prl2 can be derived either from 4" nets (Prl2-I) or 3 nets (all other modifications) of iodine atoms that are stacked along a prominent crystallographic direction, in most cases the [001] direction. Between these layers, half of the respective interstices are filled with praseodymium atoms (but see Prl2-V below). Please note that 4" and 3 nets are closely related to each other, it only needs a shear procedure to transform one net to the other (Fig. 4.3). In the iodine layers I-I distances are even shorter in the 4" net (386 in Prl2-I [4]) than in the 3 net of Prl2-IV (426.5 pm [6, 9]). 

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