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New possibilities

Certain new possibilities of twist cells with weak boundary anchoring were predicted [27, 30, 31, 109]. They are as follows [95]  [Pg.171]

The effect of saturation, i.e., total reorientation of the twist director alignment to the homeotropic one at finite voltage values. This effect could be used for the realization of memory states [30]. [Pg.171]

If the directors in the twist cell are tilted at the boundaries, and for sufficiently high voltages the tilt tends to increase, then at a certain critical angle a twist state disappears and transforms to a quasi-homeotropic con- [Pg.171]

If the electrodes of a cell which have been pretreated by rubbing are further coated with a layer of surfactant (e.g., lecithin), the resulting orientation of the molecules of the nematic liquid crystal will be homeotropic. A cell formed in such a way that the directions of initial rubbing are perpendicular to each other transmits light under parallel polars. In an electric field a nematic liquid crystal with negative dielectric anisotropy (e.g., MBBA) must reorient itself into a twist structure, and transmission through the cell decreases to zero (reverse twist effect) [51]. [Pg.172]

This effect has been observed experimentally in comparatively thick cells (d 50 /xm) [113]. In cells with d 20 /xm, the final twisted state (in the field) proves to be insufficiently stable and the nematic liquid crystal layer is gradually transformed into a planar structure. The addition of small quantities of cholesteric liquid crystals to the initial nematic mixture enables a stable twisted structure to be achieved with the application of a field and improves the electrooptical characteristics of the device. The electrooptical response of electrically induced twist nematic cells includes intensity oscillations observed both in the switching on and switching off regimes [114]. These oscillations take place due to the variation of birefringence, which are not important in the usual twist effect. [Pg.172]


More powerful computers. Associated with analytical instruments, computers have provided the latter with many new possibilities. [Pg.296]

Because the system is meant to be used for a variety of heat exchangers we could not use a simple (ANN) classifier, but we chose for a CBR type system. The case-base stores signal shapes with corresponding classifications or actions to be taken (e.g. signal mixing). Beftxe each inspection the case-base is filled with data from calibration pipes oc a case-base from a previous similar inspection can be used. For each new possible defect signal a search is done in the case base for the most similar case. [Pg.102]

New Possibilities in Neutron Radiography with Imaging Plates. [Pg.505]

The metal-ceramic X-ray tubes described here provide new possibilities to the developer of X-ray equipment ... [Pg.537]

We showed that experimentally recorded DACs and synthetically generated DGS curves are equivalent if the described requirements are fulfilled. Consequently an echo amplitude evaluation program has been developed which combines both techniques in one instrument. The software of the new state-of-the-art Ultrasonic Notebook USLT 2000 allows, apart from many other new possibilities, the combined or exclusive use of the reference block and the DGS method for amplitude evaluation. Even in those situations where DACs cannot be re-... [Pg.817]

Heinz K and Muller K 1982 LEED intensities—experimental progress and new possibilities of... [Pg.1777]

Brief description of new possibilities for surface investigations with higlily brilliant synchrotron x-ray sources. [Pg.2760]

The more reeent eombination of standardized eompressor modules and eustomized eomponents with integrally geared radial turbines has opened new possibilities. Integrally geared radial turboexpanders represent eonsiderable design flexibility and this, in turn, allows... [Pg.129]

As an illustration of the biased sampling method in application to the problems of polymer chain adsorption on a hard wall we shall recall here briefly the procedure used on a diamond lattice [35]. Starting the chain at the origin, the first bond is fixed at the plane and all the following bonds are determined at random apart from the non-reversal condition. Suppose, after a certain number i of steps, that the (/+l)st monomer reaches the plane at z = 0 again. With = 4 on the diamond lattice one has the probability p = /3 for each new possible choice of a bond. Thus in... [Pg.560]

R. A. Hulse and J. H. Taylor (Princeton) discovery of a new type of pulsar, that has opened up new possibilities for the study of gravitation. [Pg.1304]

It is a hallmark of the structure activity relationships of the corticoids that the effects of structural modifications that lead to increased potency are usually additive. The fact that more than half a dozen such modifications each lead to increased potency opens ever new possibilities for combinations and permutations. Meclorisone dibutyrate (74) thus combines the known... [Pg.95]

We must start with fluid behavior to understand the basic concepts of unified chromatography. We must forget most of what we know from common experience about liquid and gas behavior since this experience is tied with ambient conditions. Instead, we must embrace the new possibilities afforded by temperatures and pressures that are different from ambient. This new view requires phase diagrams (17, 18). [Pg.153]

The wide electrochemical windows of ionic liquids, in combination with their ability to serve as solvents for transition metal catalysts, opens up new possibilities for a combination of electrochemistry and transition metal catalysis. A very exciting first example has recently been published by Bedioui et al. [27]. [Pg.354]

In the meantime another development had decisively altered the outset situation plastics had been discovered and synthesized, among them also some acid-stable ones such as phenol-formaldehyde resin or poly(vinyl chloride) (PVC). These opened up new possibilities cellulose papers could be impregnated with phenol-formaldehyde resin solution and thus rendered sufficiently acid-stable, and sintered sheets from PVC powder were developed. Independent separators producers were founded, combining knowledge of the chemical industry with experience of the battery industry and thus accelerating the development process. [Pg.252]

Essentially all allylsilanes (M = SiR3, Section D.l.3.3.3.5.) with the exception of fluorosil-iconates11 and most of the trialkyl(allyl)stannancs (Section D.l. 3.3.3.6.), which have only very weak Lewis acidic properties, require a strong Lewis acid to trigger the reaction with a carbonyl compound by the preceding formation of an x-oxycarbenium ion, which attacks the allylic compound in an ionic open-chain pathway. These Lewis acid catalyzed carbonyl additions offer new possibilities for the control of the simple and induced diastereoselectivity12. [Pg.209]

As it will be shown the presence of an aromatic amino group in the macromolecule of modified PAN offers new possibilities for graft copolymers without the formation of a homopolymer. [Pg.107]

Goudet C, Binet V, Prezeau L et al (2004) Allosteric modulators of class-C G-Protein coupled receptors open new possibilities for therapeutic application. Drug Discov Today Ther Strat 1 125-133... [Pg.763]

Two relatively new techniques, matrix assisted laser desorption ionization-lime of flight mass spectrometry (MALDI-TOF) and electrospray ionization (FS1), offer new possibilities for analysis of polymers with molecular weights in the tens of thousands. PS molecular weights as high as 1.5 million have been determined by MALDI-TOF. Recent reviews on the application of these techniques to synthetic polymers include those by Ilantoif54 and Nielen.555 The methods have been much used to provide evidence for initiation and termination mechanisms in various forms of living and controlled radical polymerization.550 Some examples of the application of MALDI-TOF and ESI in end group determination are provided in Table 3.12. The table is not intended to be a comprehensive survey. [Pg.143]

Miniaturization is a growing trend in the field of analytical chemistry. The miniaturization of working electrodes not only has obvious practical advantages, but also opens some fundamentally new possibilities (77-79). The term microelectrode is reserved here for electrodes with at least one dimension not greater than 25 pm. [Pg.128]

Human skin compatibility has a high priority in manual dishwashing detergents. Recently, it was shown that there are some new possibilities to lower the Zein number by intelligent formulations. The Zein number is a common measure of the denaturation of protein under controlled conditions [84], A better... [Pg.200]

The finding of preparatively available iminoboranes RB = NR some years ago opened exciting new possibilities not only in B—N chemistry, but also in coordination chemistry. The first examples of iminoborane-transition-metal complexes have now been published. The structurally completely characterized t-BuB = NBu-t adds, like its alkyne analog, to the 03(00)5 fragment as a bridging ligand. When Co2(CO)g and t-BuB = NBu-t are dissolved in pentane at 0°C, warming to RT and evaporation of unreacted iminoborane yields (t-BuBNBu-t)Co2(CO)5 (86%) as a black solid, which can be recrystallized from ether-nitromethane (1 3) ... [Pg.67]

A large fraction of the hazardous waste generated in industry is in the form of dilute aqueous solutions. The special challenges of separation in highly dilute solutions may be met by the development of new, possibly liquid-filled, membranes by processes involving selective concentration of toxic chemicals on the surfaces of particles or by the use of reversed micelles. [Pg.136]

The rapid rise in computer power over the last ten years has opened up new possibilities for modelling complex chemical systems. One of the most important areas of chemical modelling has involved the use of classical force fields which represent molecules by atomistic potentials. Typically, a molecule is represented by a series of simple potential functions situated on each atom that can describe the non-bonded interaction energy between separate atomic sites. A further set of atom-based potentials can then be used to describe the intramolecular interactions within the molecule. Together, the potential functions comprise a force field for the molecule of interest. [Pg.42]

The following transformations indicate some of the new possibilities for synthetic work (58, 60, 64-66). [Pg.16]

The aim of this short review was to signal the new possibilities offered by the fast-expanding repertoire of biocatalytic methods and approaches. These recent achievements make it possible to optimize enzymatic processes on levels reserved previously only for synthetic catalysts, and also to reach far beyond, employing the special features and origin of proteins. [Pg.116]

The selectivity of the catalyst is of major importance in the case of chlorinated VOCs the oxidation products should not contain even more harmful compounds than the parent-molecule, for example, formation of dioxins should be avoided. In addition, the minimization of CI2 and maximization of HCl in a product gas should be achieved [61]. These are just a few examples of why researchers are continuing the search for VOC oxidation catalysts as well as new reactor concepts. The new possibilities include, for example, utilization of nanosized gold catalysts in the oxidation of sulfur-containing VOCs and microwave-assisted processes where combination of adsorption and oxidation is used in low-concentration VOC oxidation [62, 63]. [Pg.152]

A broader and more important implication of the oxychlorides is the potential of expanding the ligand combination to other transition-metal cluster systems. The advances in soft-chemistry techniques open up new possibilities for the sta-... [Pg.100]

These results have demonstrated that the biomimetic approach of copying the supramolecular principle of archaeal cell envelopes opens new possibilities for exploiting functional hpid membranes at meso- and macroscopic scales. Moreover, this technology has the potential to initiate a broad spectrum of developments in such areas as sensor technology, diagnostics, biotechnology, and electronic or optical devices. [Pg.380]


See other pages where New possibilities is mentioned: [Pg.253]    [Pg.101]    [Pg.177]    [Pg.209]    [Pg.111]    [Pg.24]    [Pg.308]    [Pg.245]    [Pg.72]    [Pg.288]    [Pg.380]    [Pg.622]    [Pg.669]    [Pg.1138]    [Pg.913]    [Pg.761]    [Pg.197]    [Pg.38]    [Pg.365]    [Pg.276]    [Pg.289]    [Pg.299]    [Pg.383]   
See also in sourсe #XX -- [ Pg.15 ]




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