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1. An act that requires use of resources or time. In Program Evaluation and Review Technique (PERT), an activity is represented by an arrow on a PERT chart.

2. In investing, the amount of a security's relative trading volume; that is, the amount of money flowing into and out of a security in trading. A high amount of activity means that many shares of the security are being bought and sold at a high rate, while a low level of activity indicates the opposite.


The amount of relative trading volume in a security.
References in periodicals archive ?
At the frequencies of 5 THz and 8 THz, we obtain [eta] = 0 where it corresponds to a pure optical activity, which means that the incident wave is linearly polarized, the transmitted wave is still linearly polarized but with a rotated angle [theta].
The subject of the public contract is the delivery of a single piece spectrometer Raman optical activity with facilities enabling measurement and study of manifestations of optical activity of chiral molecules, mainly present in the pharmaceutical preparations, the scope and specification of technical conditions specified in the tender documents.
Optical activity presented in helix structures in terms of chirality parameter, [kappa], has been reported [1,2].
Comparison of the capabilities of the ORD and CD techniques shows that within the wavelength range outside of the absorption bands of the chromophores (which, for the given aminopolysaccharide, falls within the far UV range), optical rotatory spectroscopy in some cases yields more information on optical activity and its correlation with other physical and chemical parameters of chitosan.
Vibrational optical activity; principles and applications.
In the realm of drug discovery, chapters discuss sampling techniques and fiber-optic probes, application to combinatorial chemistry, determination of structure-activity relationships in molecular bonding, applications of vibrational optical activity in the pharmaceutical industry, and characterization and optimization of chemical synthesis using real-time vibrational spectroscopy.
Differences include altered magnetic properties, altered electrical or optical activity, increased structural integrity, and enhanced chemical and biological properties.
The structure and electronic spectrum of binapthol are being investigated to provide quantitative data to test theories relating optical activity to molecular structure.
Using SNOM technology in materials research, it is possible to look at the optical activity of single clusters or nanoparticles.
Crystal asymmetry could be one reason for this optical activity, but it could not be the sole reason.
[UKPRwire, Wed Mar 20 2019] Automatic Polarimeter: Introduction Polarimeter refers to a device used for gauging the optical activity of a fluid.
Tenders are invited for Spectrometer Raman optical activity (open procedure, supplies)