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Method of visualization

Another method of visualization uses a rectangular mold which is not completely filled... [Pg.190]

Visual comparison of spot intensity and/or size to a standard amount of the same pesticide run on the same TLC plate. This provides an estimation of the substance with approximately 20% accuracy. A detailed description of this method of visual estimation of thin layer chromatographs has been given by Johnson(21), who has very wisely commented that it is better to be "approximately right than precisely wrong". [Pg.264]

Keywords method of visualization, acoustic microscopy, subsurface layers, nanopore density, elastic-mechanical steel parameters, nondestructive evaluation. [Pg.451]

By means of method of visualization with the help of acoustic waves [1,2] we could get the microstructure images of steel samples on different depths from the surface. The analysis of acoustic images gave the possibility to calculate the dimensions of grains, to observe their transformation in the period of time or under external influences. In accordance with the theory of Hall - Peach there were defined the strength characteristics, for example flow limit ( Go,2) of the materials under study. The significance obtained o0 2 is in proper correspondence with values that are table one for the type of steel under consideration. [Pg.452]

The compound is eluted from the chromatographic plate, collected, and introduced into the mass spectrometer as a discrete sample. In this method, samples collected from a TLC spot, identified with an independent method of visualization, must be sufficiently volatile to evaporate into the source of the mass spectrometer. [Pg.1624]

Methods of visualization that are useful in interpreting the dynamics of ecological structures are also available. In the past, numerous graphs of each variable over the course of the experiment were plotted and a pattern searched for by the investigator. Again, there is a danger that important relationships could be missed because of the bias of the investigator or the simple intractability of the patterns. Other methods are available. [Pg.65]

One of the difficulties of ecosystem-level analysis has been our inability to accurately present the dynamics of these multidimensional relationships. Conventional univariate statistics are still prevalent, although the shortcomings of these methods are well known. Several researchers have proposed different methods of visualizing ecosystems and the risks associated with xenobiotic inputs. [Pg.376]

Circos is a software package for visualizing data and information (http // circos.ca) in a circular layout. This new and attractive method of visualizing... [Pg.451]

The ision ])rocess is tlierefore prone to various influences which can affect the perception of detail, briglitness, contrast and colour. Through tests such as those used to examine for colour blindness, the Camouflage Section was able to identify optical illusion-type effects and other methods of visual confusion utilising particular mixes of colours, all of which were incorporated in systems of protective painting for ships. [Pg.118]

Computers provide unique methods of visualizing three-dimensional structure and unique ways of describing biochemical processes with interactive cartoons. One of us, Harry R. Matthews, maintains a site for this purpose at http //mobv. ucdavi s. edu/HRM. [Pg.48]

The above two methods of indication do not depend on the half-reaction potentials, although the completeness of the titration reaction and hence the sharpness of the end point do. Examples of these first two methods of visual indication are few, and most types of redox titrations are detected using redox indicators. These are highly colored dyes that are weak reducing or oxidizing agents that can be oxidized or reduced the colors of the oxidized and reduced forms are different. The oxidation state of the indicator and hence its color will depend on the potential at a given point in the titration. A half-reaction and Nemst equation can be written for the indicator ... [Pg.422]

Background Covalent bonding occurs when atoms share valence electrons. In the Valence Shell Electron Pair Repulsion (VSEPR) theory, the way in which valence electrons of bonding atoms are positioned is the basis for predicting a molecule s shape. This method of visualizing shape is also based on the molecule s Lewis structure. [Pg.272]

Development of a method of visual surveillance of conditions of refractory, electrodes, and other units of the melter during its operation and after decommissioning. [Pg.90]

The choice of the strates (purify mitochondria, purify mtDNA, work with total DNA) and the choice of the technics to be used to prepare the extracts depend on numerous parameters equipment of the laboratory, method of visualization, size of the smallest fragments (function of the mtDNA and on the enzymes used), number of strains analysed... [Pg.297]

A visual examination should be made to yield information on the general condition of the part, component or surface to be examined, including such conditions as the presence of scratches, wear, cracks, corrosion or erosion on the surface, or evidence of leaking. Optical aids such as television cameras, binoculars and mirrors may be used. Surface rephcation as a method of visual examination may be considered acceptable, provided that the resolution at the surface is at least equivalent to that obtainable by visual observation. Any visual examination that requires a clean surface or decontamination for the proper interpretation of results should be preceded by appropriate cleaning processes. [Pg.62]

In this paper, we introduced a technique for analyzing tasks of en route ATC using the framework of distributed cognition as an approach to study problems of human factors in an ATC system. The analysis method of team cooperative work combines the concepts of TSA and mutual behef, and an ethnographical study. Moreover, we developed a method of visualization for team cooperative work from cognitive process perspective. [Pg.1731]

Fluorochromes are visualized by excitation with light of one (excitation) wavelength and imaging emitted fluorescence at another (emission) wavelength using appropriate filters. The properties and methods of visualization of the fluorochromes fluorescein and rho-damine, which are used to detect digoxigenin, are the same as for direct fluorochrome-labeled probes and are outlined in Chapter 26. [Pg.178]

Visual or other methods of visualization of the surface can provide a significant amount of information on the nature of the surface. [Pg.240]

Fig.4. The distribution of a contaminant is examined by reconstructing images of an acrylic fiber contaminant on a microcircuit die using various methods of visualization. Image generation methods include the use of a absorbance intensity at 2968 cm, b integrated absorbance between 2850 and 3000 cm"b C integrated absorbance from 1000 to 4000 cm , and d the Gram-Schmidt method, (reproduced from Ref. [31])... Fig.4. The distribution of a contaminant is examined by reconstructing images of an acrylic fiber contaminant on a microcircuit die using various methods of visualization. Image generation methods include the use of a absorbance intensity at 2968 cm, b integrated absorbance between 2850 and 3000 cm"b C integrated absorbance from 1000 to 4000 cm , and d the Gram-Schmidt method, (reproduced from Ref. [31])...
Two methods of visualization will be used to observe the positions of the spots on the developed TLC plates. First, the plates will be observed while under illumination from a short-wavelength ultraviolet (UV) lamp. This is best done in a darkened room or in a fume hood that has been darkened by taping butcher paper or aluminum foil over the lowered glass cover. Under these conditions, some of the spots will appear as dark areas on the plate, while others will fluoresce brightly. This difference in appearance under UV illumination will help to distinguish the... [Pg.91]

When the thin-layer plate has been developed, it is removed from the developing tank and allowed to dry until it is free of solvent. If the mixture that was originally spotted on the plate was separated, there will be a vertical series of spots on the plate. Each spot corresponds to a separate component or compound from the original mixture. If the components of the mixture are colored substances, the various spots will be clearly visible after development. More often, however, the "spots" will not be visible because they correspond to colorless substances. If spots are not apparent, they can be made visible only if a visualization method is used. Often, spots can be seen when the thin-layer plate is held under ultraviolet light the ultraviolet lamp is a common visualization method. Also common is the use of iodine vapor. The plates are placed in a chamber containing iodine crystals and left to stand for a short time. The iodine reacts with the various compounds adsorbed on the plate to give colored complexes that are clearly visible. Because iodine often changes the compounds by reaction, the components of the mixture cannot be recovered from the plate when the iodine method is used. (Other methods of visualization are discussed in Section 20.7.)... [Pg.811]

The second most common method of visualization is by an ultraviolet (UV) lamp. Under UV light, compounds often look like bright spots on the plate. This often suggests the structure of the compound Certain types of compounds shine very brightly under UV light because they fluoresce. [Pg.818]

If you use large plates (Section 20.3B), materials can be separated, and the separated components can be recovered individually from the plates. Plates used in this way are called preparative plates. For preparative plates, a thick layer of adsorbent is generally used. Instead of being applied as a spot or a series of spots, the mixture to be separated is applied as a line of material about 1 cm from the bottom of the plate. As the plate is developed, the separated materials form bands. After development, you can observe the separated bands, usually by UV light, and outline the zones in pencil. If the method of visualization is destructive, most of the plate is covered with paper to protect it, and the reagent is applied only at the extreme edge of the plate. [Pg.819]


See other pages where Method of visualization is mentioned: [Pg.1326]    [Pg.327]    [Pg.313]    [Pg.104]    [Pg.99]    [Pg.264]    [Pg.41]    [Pg.115]    [Pg.233]    [Pg.542]    [Pg.66]    [Pg.450]    [Pg.127]    [Pg.313]    [Pg.615]    [Pg.212]    [Pg.231]    [Pg.211]    [Pg.209]    [Pg.250]    [Pg.251]    [Pg.184]    [Pg.2327]   
See also in sourсe #XX -- [ Pg.435 ]

See also in sourсe #XX -- [ Pg.435 ]




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