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Further improvements

Figure 15 shows results for a difficult type I system methanol-n-heptane-benzene. In this example, the two-phase region is extremely small. The dashed line (a) shows predictions using the original UNIQUAC equation with q = q. This form of the UNIQUAC equation does not adequately fit the binary vapor-liquid equilibrium data for the methanol-benzene system and therefore the ternary predictions are grossly in error. The ternary prediction is much improved with the modified UNIQUAC equation (b) since this equation fits the methanol-benzene system much better. Further improvement (c) is obtained when a few ternary data are used to fix the binary parameters. [Pg.66]

However, coiled tubing drilling is limited to slim holes, and the reliability of some of the drill string components such as downhole motors needs further improvement. Presently, the cost of building a new customised CTD rig limits the wider application of this emerging technology. [Pg.53]

Tests were done on real data containing approx. 32(XX) nontrivial images. Of these approx. 25% were classified by the rule-based system and another 25% by the CBR system. The reliability was high - of 330 defects present in the data only two were classified as non-defects. We are currently working on further improving the recognition ratio and increasing the speed of the system. [Pg.102]

Special probe geometries and combinations of different types of magnetic field sensors make an important contribution to the further improvement of the eddy-current testing method and results in new applications. [Pg.365]

During testing a depth resolution of 50-80 micron and a lateral resolution of 20-40 micron was achieved. The spatial resolution was limited not mainly hy source or camera properties, but by the accuracy of compensation of the instrumental errors in the object movements and misalignments. According to this results a mote precision object rotation system and mote stable specimen holding can do further improvements in the space resolution of microlaminography. [Pg.572]

Laminographical approaches can be used for layer-by-layer visualization of the internal microstructure for the flat objects (multilayers, PCBs etc.), that caimot be reconstructed by computerized tomography because of the limited possibilities in rotation. Depth and lateral spatial resolutions are limited by the tube, camera and rotation accuracy. Microfocus X-ray tubes and digital registration techniques with static cameras allow improving resolution. Precision object manipulations and more effective distortion corrections can do further improvement. [Pg.572]

Both options 2 and 3 are compatible with our long term innovation strategy to further improve ecology as well as speed and user-friendliness of classical industrial radiography. [Pg.609]

Although the processing time unit basically could be further improved table 1 gives some idears what the achieved results and axial resolution mean in several interesting applications and low center frequencies. With low frequencies a lot of attenuation problems available in new engineered materials could be solved. [Pg.843]

It would also be of interest to investigate if the attenuation estimates can be further improved by extending our input data vectors. Since attenuation (and porosity) is spatially correlated, we should expect improvements when including data from A-.scans in a neighbourhood around the point of interest. This is also a topic for future work. [Pg.893]

Further improvements on typical signal distance rules will certainly reduce the tremendous workload of online analysis. This new approach will lead to a reduction of the on-site analyst team. [Pg.1026]

This integral equation can be solved by expansion of the integrand in bipolar coordmates [2, 3], Further improvement to the PY equation can be obtamed by analytical fit to simulation studies as described below. [Pg.563]

The integral under the heat capacity curve is an energy (or enthalpy as the case may be) and is more or less independent of the details of the model. The quasi-chemical treatment improved the heat capacity curve, making it sharper and narrower than the mean-field result, but it still remained finite at the critical point. Further improvements were made by Bethe with a second approximation, and by Kirkwood (1938). Figure A2.5.21 compares the various theoretical calculations [6]. These modifications lead to somewhat lower values of the critical temperature, which could be related to a flattening of the coexistence curve. Moreover, and perhaps more important, they show that a short-range order persists to higher temperatures, as it must because of the preference for unlike pairs the excess heat capacity shows a discontinuity, but it does not drop to zero as mean-field theories predict. Unfortunately these improvements are still analytic and in the vicinity of the critical point still yield a parabolic coexistence curve and a finite heat capacity just as the mean-field treatments do. [Pg.636]

At present, the data base used for the fit was not specially selected to avoid homologous proteins. Thus, a further improvement can be expected from using data for one of the specially prepared lists of PDB files (cf. Hobohm et al. [9]). We also expect further improvements from replacing the polynomial fits in the potential estimation procedure by piecewise cubic fits though at the moment it is not clear how to select the number of nodes needed to get a good but not overfitting approximation to the density. Finally, we are considering... [Pg.221]

Notes and Comments. Further improvements in efficiency were achieved by implementing the method on computers with highly parallel architecture. SISM performs in parallel as LFV which means the speed up Is gained due to longer time stop wliidi cun be u.sed by SISM [20]. [Pg.345]

MM2 was, according the web site of the authors, released as MM2 87). The various MM2 flavors are superseded by MM3, with significant improvements in the functional form [10]. It was also extended to handle amides, polypeptides, and proteins [11]. The last release of this series was MM3(%). Further improvements followed by starting the MM4 series, which focuses on hydrocarbons [12], on the description of hyperconjugative effects on carbon-carbon bond lengths [13], and on conjugated hydrocarbons [14] with special emphasis on vibrational frequencies [15]. For applications of MM2 and MM3 in inorganic systems, readers are referred to the literature [16-19]. [Pg.350]

And last not least, we will have to see further improvements in the graphical user interfaces of software systems and the retrieval systems of databases in order to make software and databases more acceptable to the chemical community at large. Software and databases should speak the language a chemist is used to, with hand-drawn chemical structures and reaction equations, or even imderstand the spoken word - and only provide the desired information selectively, not buried in a phe of unnecessary output. [Pg.625]

Basis sets can be further improved by adding new functions, provided that the new functions represent some element of the physics of the actual wave function. Chemical bonds are not centered exactly on nuclei, so polarized functions are added to the basis set leading to an improved basis denoted p, d, or f in such sets as 6-31G(d), etc. Electrons do not have a very high probability density far from the nuclei in a molecule, but the little probability that they do have is important in chemical bonding, hence dijfuse functions, denoted - - as in 6-311 - - G(d), are added in some very high-level basis sets. [Pg.311]

A further improvement is embodied in the Klndler variation of the Willgerodt reaction this consists in heating the ketone with approximately equal amounts of sulphur and a dry amine instead of aqueous ammonium polysulphide. The principal product is a thioamide, and hydrolysis with acid or alkali affords the carboxylic acid, usually in good yield. [Pg.923]

A catalytic enantio- and diastereoselective dihydroxylation procedure without the assistance of a directing functional group (like the allylic alcohol group in the Sharpless epox-idation) has also been developed by K.B. Sharpless (E.N. Jacobsen, 1988 H.-L. Kwong, 1990 B.M. Kim, 1990 H. Waldmann, 1992). It uses osmium tetroxide as a catalytic oxidant (as little as 20 ppm to date) and two readily available cinchona alkaloid diastereomeis, namely the 4-chlorobenzoate esters or bulky aryl ethers of dihydroquinine and dihydroquinidine (cf. p. 290% as stereosteering reagents (structures of the Os complexes see R.M. Pearlstein, 1990). The transformation lacks the high asymmetric inductions of the Sharpless epoxidation, but it is broadly applicable and insensitive to air and water. Further improvements are to be expected. [Pg.129]

Improvements ia membrane technology, vahdation of membrane iategrity, and methods to extend filter usage should further improve the performance of membrane filters ia removal of viral particles. Methods to improve or extead filter life and iacrease flow rates by creating more complex flow patterns could possibly be the focus of the next generation of membrane filters designed to remove viral particles. [Pg.145]

The yield can be raised to 28% if the Hofmann elimination is conducted in the presence of a water-soluble copper or iron compound (19). Further improvements up to 50% were reported when the elimination was carried out in the presence of ketone compounds (20). Further beneficial effects have been found with certain cosolvents, with reported yields of greater than 70% (8). [Pg.430]

Acryhc polymers are fairly iasensitive to normal uv degradation siace the primary uv absorption of acryhcs occurs below the solar spectmm (59). The iacorporation of absorbers, such as i9-hydroxyben2ophenone [117-99-7] further improves the uv stabihty (59). Under normal use conditions acryhc polymers have superior resistance to degradation and show remarkable retention of their original properties. [Pg.164]

THPC—Urea—Dlsodium Phosphate. A further improved variation uses a combination of THPC, urea, and disodium phosphate (82,83). [Pg.489]

Further improvements in anode performance have been achieved through the inclusion of certain metal salts in the electrolyte, and more recently by dkect incorporation into the anode (92,96,97). Good anode performance has been shown to depend on the formation of carbon—fluorine intercalation compounds at the electrode surface (98). These intercalation compounds resist further oxidation by fluorine to form (CF ), have good electrical conductivity, and are wet by the electrolyte. The presence of certain metals enhance the formation of the intercalation compounds. Lithium, aluminum, or nickel fluoride appear to be the best salts for this purpose (92,98). [Pg.127]

Two undesirable aspects of FCC naphtha quaUty are that it may contain unacceptably high amounts of foul smelling mercaptans, and that its thermal stabiUty may be too low. Mercaptans are usually found in the light FCC naphtha and may be removed or converted to sulfides and disulfides by a sweetening process such as Merox, developed by UOP. Thermal stabiUty is improved in sweetening processes through removal of cresyUc and naphthenic acids. It may be further improved by clay treating and by addition of oxidation inhibitors such as phenylene diamine. [Pg.184]


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See also in sourсe #XX -- [ Pg.177 ]




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