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Time frame, short

A recent design of the maximum bubble pressure instrument for measurement of dynamic surface tension allows resolution in the millisecond time frame [119, 120]. This was accomplished by increasing the system volume relative to that of the bubble and by using electric and acoustic sensors to track the bubble formation frequency. Miller and co-workers also assessed the hydrodynamic effects arising at short bubble formation times with experiments on very viscous liquids [121]. They proposed a correction procedure to improve reliability at short times. This technique is applicable to the study of surfactant and polymer adsorption from solution [101, 120]. [Pg.35]

On the other hand, there are some ionization techniques that are very useful, particularly at very high mass, but produce ions only in pulses. For these sources, the ion extraction field can be left on continuously. Two prominent examples are Californium radionuclide and laser desorption ionization. In the former, nuclear disintegration occurs within a very short time frame to give a... [Pg.192]

Because TOF spectra are obtained in such a short time frame, additional spectra can be accumulated rapidly. Thus, in the span of one second, it is possible to accumulate several thousand mass spectra. [Pg.401]

Mobile laboratories are another alternative. If large amounts of data need to be analyzed in a short time frame, having a lab on site can be a real asset. A local lab may also provide similar service. [Pg.61]

These questions need to be considered for every emergency situation. And the workers need to be able to make judgment calls in a very short time frame. Wliether to attempt to handle an emergency or walk away and report it becomes very situation dependent. Keep in mind that situations with real-life potentials should be discussed during training. [Pg.166]

In studies of molecular dynamics, lasers of very short pulse lengths allow investigation by laser-induced fluorescence of chemical processes that occur in a picosecond time frame. This time period is much less than the lifetimes of any transient species that could last long enough to yield a measurable vibrational spectrum. Such measurements go beyond simple detection and characterization of transient species. They yield details never before available of the time behavior of species in fast reactions, such as temporal and spatial redistribution of initially localized energy in excited molecules. Laser-induced fluorescence characterizes the molecular species that have formed, their internal energy distributions, and their lifetimes. [Pg.259]

It is essential that, with the use of evidence-based medicine to inform decisions in health care, the processes used in program development be as transparent as possible. Information about the limited evidence and inherent uncertainty should be disclosed and available for scrutiny, even within the software itself. In fact, in an attempt to maximize transparency, some have advocated open source development and publication of interactive software models [49, 50]. Certainly, details of methodologies, sources, and other techniques employed for development of the underlying models must be acknowledged. However, the proprietary nature of many of these programs must be taken into consideration and measures put into place to ensure confidentiality. Requested publication of all NIH-sponsored research online (in PubMed) [51] within a reasonable time frame after journal acceptance will help to ensure that these data are available in the public domain in short order. [Pg.585]

Seeds of lettuce and other species have frequently been used to bioassay for the allelopathic activity of plant exudates (17.18.19). As with the use of cell suspensions, there are certain advantages and disadvantages to this methodology. The experimental simplicity, small amounts of material required and short time frame are certainly attractive qualities. However, species used in such bioassays quite often do not represent the actual target species under consideration. This is especially true when terrestrial crop species are substituted for weeds of aquatic systems. Nevertheless, information obtained from such experiments are often valuable when used in conjunction with results of other assays. [Pg.410]

Successful combination of a chromatographic procedure for separating and isolating additive components with an on-line method for obtaining the IR spectrum enables detailed compositional and structural information to be obtained in a relatively short time frame, as shown in the case of additives in PP [501], and of a plasticiser (DEHP) and an aromatic phenyl phosphate flame retardant in a PVC fabric [502], RPLC-TSP-FTIR with diffuse reflectance detection has been used for dye analysis [512], The HPLC-separated components were deposited as a series of concentrated spots on a moving tape. HPLC-TSP-FTIR has analysed polystyrene samples [513,514], The LC Transform has also been employed for the identification of a stain in carpet yarn [515] and a contaminant in a multiwire cable [516], HPLC-FTIR can be used to maintain consistency of raw materials or to characterise a performance difference. [Pg.496]

Plant-protection products are used in agriculture, horticulture, and elsewhere in order to prevent major yield and quality losses. They are an integral part of various types of crop maintenance measures. This means that other maintenance activities may make it necessary to re-enter treated areas relatively shortly after application (i.e., within the normal time frame for major plant-protection activities). The type of work to be done and the point of time for re-entering relative to the time of application of a plant-protection product may vary from crop to crop. [Pg.108]

Another approach is that of including dynamics in the calculations. A dynamical formalism of DFT was first developed by Car and Parrinello [31], and has been employed in a wide range of areas, e.g. solvation problems, reactions on surfaces, solid-state interactions, and a variety of biochemical applications. In CP-MD one normally uses a plane wave basis to reduce the computational requirements and enable easy implementation of periodic boundary conditions. Nonetheless, CP-MD simulations are rather costly, and are normally not applied to systems larger than, say, 1-200 atoms, and over relatively short time frames. [Pg.123]

The selection of building blocks is based on information derived from, for example, computational chemistry, where potential virtual ligand molecules are modeled to fit the receptor-protein binding site. Combinatorial chemistry commences with a scaffold or framework to which additional groups are added to improve the binding affinity. Compounds are prepared and later screened using HTS. In this way, many compounds are tested within a short time frame to speed up drug discovery. [Pg.73]


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See also in sourсe #XX -- [ Pg.388 , Pg.389 , Pg.390 , Pg.391 , Pg.399 ]




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