Orientation characteristic

C-alkylation of secondary and tertiary aromatic amines by hexafluoroacetone or methyl trifluoropyruvate is performed under mild conditions [172] (equation 147) The reaction of phenylhydrazme with hexafluoroacetone leads selectively to the product of the C-hydroxyalkylation at the ortho position of the aromatic ring The change from the para orientation characteristic for anilines is apparently a consequence of a cyclic transition state arising from the initial N hydroxy alky lation at the primary amino group [173] (equation 148)... 

The study on commercial HDPE samples could not provide a correlation of the izod impact test with the field performance test, i.e., drop impact resistance on moulded products [113]. It was found that the sample of highest density and lowest izod impact strength passed the drop impact test, but other samples of lower density and higher izod impact strength could not withstand shock loading by drop impact and failed in brittle manner. This may be due to the fact that velocities and modes of loading vary widely in different impact tests. It has been reported that even the qualitative agreement between the different impact tests is poor because the test bars and moulded products often have different orientation characteristics, particularly near the surface [115]. 

A method that creates patterned micro-structures distributed on the bottom wall of the micro-channel was proposed by Yang et al. (2006). A roughened bottom wall was created using the crystal orientation characteristics of the wafers. 

Data systems that participate in a federation can be very heterogeneous both in their content and implementation. In a federated system, it is a great advantage to define communication in terms of external abstraction rather than in terms of internal computer representation. This is not so true for unified systems, where the imposition of a specific data model among components makes it more reasonable to define communication in terms of computer-oriented characteristics and assumptions. 

Opopanax oil and resinoid are used in perfume compositions with oriental characteristics, the resinoid also for its fixative properties, [8021-36-1], [100084-96-6]. 

The compatibility, mechanical properties, and segmental orientation characteristics of poly-e-caprolactone (PCL) blended with poly (vinyl chloride) (PVC) and nitrocellulose (NC) are described in this study. In PVC blends, the amorphous components were compatible from 0-100% PCL concentration, while in the NC system compatibility teas achieved in the range 50-100% PCL. Above 50% PCL concentration, PCL crystallinity was present in both blend systems. Differential IR dichroism was used to follow the dynamic strain-induced orientation of the constituent chains in the blends. It was found for amorphous compatible blends that the PCL oriented in essentially the same manner as NC and the isotactic segments of PVC. Syndio-tactic PVC segments showed higher orientation functions, implying a microcrystalline PVC phase. 

In Ref. [257], Sii- Cx alloy films with x< 0.1 were deposited on Si by molecular beam epitaxy (MBE) to use them for the substrates of heteroepitaxial diamond films. It was expected that when x = 4.33%, a perfect lattice match of Sii C c D = 2 3 occurs and the degree of orientational alignment could be improved. An EIOD film, grown to a thickness of 20 pm using the BEN process, successfully resulted in a (100)-oriented film with (100) faces at the film surface, but the FWHM of the (111) XPF was 6°, the same value as when the direct nucleation of diamond was done on Si using BEN. The results of Raman spectroscopy and XRD of the diamond films were not dependent on the x value. It was thus confirmed that the orientational characteristics of the HOD films had no significant dependence on the C content of the Sii C,v layers. This work can be compared with that of Ref. [258], where layers with x= 1.4 and 3.5% were deposited on Si(lOO) by... 

The magnetic structures are commonly represented as a set of arrows associated with the magnetic moments, with magnitudes and orientations characteristic of the particular structure. 

Study of the crystal structure of polysaccharides, particularly of cellulose, has provided the main use for polarized infrared radiation in connection with carbohydrate spectra. Since this is another technique whereby band assignments can be made, the basic steps involved will be described in a simplified manner with reference to a polymer sample having uniaxial orientation. This is a common type of orientation, characteristic of fibers,... 

Thanks to close cooperation with a group of Italian scientists, the following market-oriented characteristics could he defined and objectively measured for the 19 main treatment alternatives (listed in Table 3.1) used in... 

At the initial stage of extrusion, the parallel lamellae rotated or tilted to form inclined lamellar stacks and the perpendicular lamellae tended to increase in number. The perpendicular lamellae increased up to around EDR 4.6 in the second stage where the inclined lamellae started to transform steadily into fibrils. This perpendicular lamellar orientation characteristic for extrusion drawing is likely caused by the compressive force applied for extrusion. Such an effect of the compressive force has bran more clearly observed in our previous study of crystalline-state extrusion of polyethylene single crystal powder (21). 

High stress flows cause what is referred to as c-axis orientation along the machine direction. This would mean that in Fig. 3.41, the machine direction was the vertical direction. Since one of the critical parameters for many films is the permeability, this orientation characteristic is important. Permeation cannot occur through the crystallites, so orientation in the thickness direction of the film would provide maximum barrier. This type of orientation cannot be achieved, but the right choice of polymer and processing conditions can provide a random orientation of the lamellae. 

Overview of the orientational characteristics of chain molecules incorporated in the nematic state... 

Overview of the Orientational Characteristics of Chain Molecules Incorporated in the Nematic State... 

Abe, A., and Furuya, H., Orientational characteristics of main-chain polymer liquid crystals as revealed by the rotational isomeric state analysis of deuterium NMR spectra, Macro-molecules, 22, 2982-2987. (1989). 

In T walls there is a change in orientation characteristic of twinning. 

Nonwoven geotextiles. Nonwoven fabrics are defined as a sheet, web, or batt of directionally or randomly oriented fibres/filaments, bonded either by friction, and/or cohesion, and/or adhesion. In general, nonwoven fabric formation can be considered as a two-step process web formation (aligning the fibres with certain orientation characteristics) and bonding these fibres by mechanical, thermal, or chemical means. This two-step process has formed the classification of nonwoven structures, i.e. carded, airlaid, spunlaid, meltblown, needlepunched, hydroentangled, adhesive bonded, thermal bonded, stitch bonded, etc. Some of the important processes that are used for the manufacture of nonwoven geotextiles are discussed below. 

The NMR technique has provided useful information regarding the orientational characteristics of nematic liquid crystals [96]. In many examples, the order parameters of the mesogenic core comprising a linear array of aromatic nuclei have been accurately determined from the observed dipolar (Dhd) and quadrupolar (Av) splittings by using deuterium-substituted samples. An attempt was made to elucidate the nematic conformation of the polymethylene-type spacer involved in dimer compounds, o, ct)-bis(4-cyanobiphenyl-4 -yloxy)alkanes (CBA- , with = 9,10), by the combined use of NMR and RIS analysis. The chemical structures and the phase transition data obtained by differential scanning calorimetry (DSC) are shown in... 

Fig. 5. At the left, molecules of normal hemoglobin or of oxygenated sickle-cell-anemia hemoglobin are shown, with random orientations, and at about the average distance apart characteristic of red-cell contents. At the right long strings of molecules of deoxygenated sickle-cell-anemia hemoglobin are shown, assuming the parallel orientation characteristic of the nematic liquid crystals that presumably form within the red cells in the venous blood of patients with sickle-cell anemia, and twist the red cells into the abnormal shape characteristic of the disease.

Liquid crystals do not lend themselves to electron microscopy, as a liquid phase cannot be easily handled within a vacuum column unless cumbersome wet stages are employed. However, the fact that polymeric liquid crystals can be quenched to the glassy or partially crystalline states without any apparent disturbance of the local orientation characteristic of the liquid mesophase means that the electron microscope becomes a most useful tool. It is now providing new insights into the local molecular orientation in some liquid crystal polymer systems. 

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