Pseudo Type

Hirsutine (58), the pseudo isomer of corynantheidine and dihydrocory-nantheine, has been elegantly synthesized by Wenkert and his collaborators (161). The reaction of keto diester290 with Meerwein s reagent, followed by hydrogenation, resulted in pseudo-type diester 321, which on reduction and methylation gave ( )-hirsutine (161). 

Using X-ray diffraction crystallographic analysis, it has been concluded that incorporation of an azaproline residue (8, see Scheme 4) into a peptide, in contrast to Pro itself, should destabilize the formation of any type of (3-turn with the residue following it, but could accommodate a folded structure with a pseudo type-VI 3-turn with the preceding residue.171 ... 

It is striking that the high compaction pressure, which was sufficient to convert assemblages of spheroidal particles into well-defined mesopore structures (Gregg, 1968), had relatively little effect on the course of the adsorption isotherm. Although the desorption curve was displaced in the multilayer range, the isotherm remained pseudo-Type II (now termed Type lib). We conclude that the resulting hysteresis loop is associated with both the development of a pore network and the delayed capillary condensation on the surface of the platelets. 

As indicated earlier, the isotherms in Figure 11.5 could be termed pseudo Type II isotherms, but we prefer the designation Type lib (see Figure 13.1). Such isotherms are given by either slit-shaped pores or, as in the present case, assemblages of platy particles. The fact that the montmorillonite particles are thin and flexible may be responsible for the closer proximity of the basal faces than in uncompacted kaolinite. 

Burger C, Gorbatyuk OS, Velardo MJ, Pederr CS, Williams P, Zolotukhirr S, Reier PJ, Marrdel RJ, Muzyczka N (2004) Recombirrarrt AAV viral vectors pseudo typed widr viral capsids from serotypes 1, 2, arrd 5 display differerrdal efficierrcy arrd cell tropism after delivery to differerrt regiorrs of dre cerrtral rrer vous system. Mol Tlrer 10 302-317. 

However, in most crystals containing H5O2, the ion does not have strict S5nnmetry. These then are, at best, pseudo-Type A structures. For instance, a neutron-diffraction study (83) of HAUCI4. 4 H2O shows the mid-point of to he at a crystallographic centre of symmetry,... 

Figs. 19 and 20 show the infrared spectra of some acid salts and related crystalline compounds. The spectrum in Fig. 19(a) is from an acid salt of Type B, and it approximates to a superposition of the spectra of free acid and neutral salt. The other spectra are all of Hadzi s T5q>e (ii), which is shown in its starkest form in Fig. 19(c) (sodium hydrogen diacetate) with a window near 950 cm h Potassium hydrogen malonate, a Type A structure, has a similar spectrum (20 (a)). The picoline-N-oxide hemi-hydrobromide (19(d)) is a T5q>e A basic salt Cook s basic salt (Sect. XI) is of pseudo-Type A and gives the spectrum (20(b)). Sodium bicarbonate (20(c)) and potassium hydrogen oxalate (20(d)) are acid sdts of intermediate character (see Sect. XV and XVI A). 

Fig. 20 Further infrared spectra (a) potassium hydrogen malonate (b) pseudo-Type A basic salt described in section XI (c) sodium bicarbonate (d) potassium hydrogen oxalate...

From the ephedrae herba, ephedrine and related alkaloids were isolated as the main components.These alkaloids include (—)-ephedrine and (+)-pseudo-ephedrine, (-)-norephedrine and (+)-norpseudoephedrine. Among these alkaloids, the pseudo-type alkaloids are the diastereomers at the benzylic position of the other alkaloid, respectively. 

Type II Versus Pseudo Type II Spectral Interactions... 

The standard NF T 65-004 classifies the types of composite bitumen it distinguishes three grades of bitumen-tars by their pseudo-viscosities and two grades of bitumen-coal tar pitch by their penetrabilities. 

The second type of solution polymerization concept uses mixtures of supercritical ethylene and molten PE as the medium for ethylene polymerization. Some reactors previously used for free-radical ethylene polymerization in supercritical ethylene at high pressure (see Olefin POLYMERS,LOW DENSITY polyethylene) were converted for the catalytic synthesis of LLDPE. Both stirred and tubular autoclaves operating at 30—200 MPa (4,500—30,000 psig) and 170—350°C can also be used for this purpose. Residence times in these reactors are short, from 1 to 5 minutes. Three types of catalysts are used in these processes. The first type includes pseudo-homogeneous Ziegler catalysts. In this case, all catalyst components are introduced into a reactor as hquids or solutions but form soHd catalysts when combined in the reactor. Examples of such catalysts include titanium tetrachloride as well as its mixtures with vanadium oxytrichloride and a trialkyl aluminum compound (53,54). The second type of catalysts are soHd Ziegler catalysts (55). Both of these catalysts produce compositionaHy nonuniform LLDPE resins. Exxon Chemical Company uses a third type of catalysts, metallocene catalysts, in a similar solution process to produce uniformly branched ethylene copolymers with 1-butene and 1-hexene called Exact resins (56). 

For the first time through a liqmd-liquid extrac tion problem, the right-triangular graphical method may be preferred because it is completely rigorous for a ternary system and reasonably easy to understand. However, the shortcut methods with the Bancroft coordinates and the Kremser equations become valuable time-savers for repetitive calculations and for data reduction from experimental runs. The calculation of pseudo inlet compositions and the use of the McCabe-Thiele type of stage calculations lend themselves readily to programmable calculator or computer routines with a simple correlation of equilibrium data. 

Usually, product specifications for a crude distillation unit are expressed in terms of the products 15/5 or ASTM distillation curves. The prediction of a product 15/5 distillation is accomplished simply by blending the quantities of the pseudo components in the stream so as to form a true boiling point, 15/5 equivalent, distillation curve. This curve can then be converted to an ASTM type distillation using an empirical method. Figure 5 illustrates how a typical ASTM curve compares to the 15/5 curve for the same material. 

The results of the types of reaetion being eonsidered show that the treatment of kinetie data heeomes rapidly more eomplex as the reaetion order inereases. In eases where the reaetion eonditions are sueh dial the eoneentrations of one or more of the speeies oeeurring in the rate equation remain eonstant, these terms may he ineluded in the rate eonstant k. The reaetions ean he attributed to lower order reaetions. These types of reaetions ean be defined as pseudo-nth order, where n is the sum of the exponents of those eoneentrations that ehange during the reaetion. An example of this type of reaetion is in eatalytie reaetion, where the eatalyst eoneentration remains eonstant during the reaetions. 

Appearance of the metallic structure of CNT is based on the crossing of the highest occupied (HO) and the lowest unoccupied (LU) bands (see, e.g.. Fig. 3), each accompanying pseudo rt-type crystal orbital. Note that pseudo n-type orbital, particularly when all the valence atomic orbitals (AO) are taken into consideration, implies that its main AO component is normal to the cylindrical CNT surface. The band crossing mentioned above is possible when these two... 

Data of this type can also be treated graphically. If a pseudo-first-order rate... 

A pseudo 1,2 cycloaddition (actually a 1,3 cycloaddition, but may be considered a 1,2 type if a three-membered ring is considered analogous to an alkene) is observed when the pyrrolidine enamine of cyclohexanone is allowed to react with N-carbethoxyaziridine (129) to produce octahydro-indole 130 91). Octahydroindoles and pyrrolidines can also be produced through the intramolecular alkylation of the enamines of certain halo-ketourethanes 176a). 

Thus among the known pseudo bases derived from heterocyclic quaternary ammonium salts, the following principal types can be differentiated according to their basicity ... 

As an over-all conclusion, it can be stated that the assumption of ring-chain tautomerism in the pseudo bases derived from the heterocyclic quaternary ammonium salts is quite unnecessary as an explanation of the formation of two (cyclic and open-chain) types of deriva-... 

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