Diffusion information

Besides the literature mentioned in the references, we would like to direct readers to a series of websites, whose purpose is to diffuse information on the current research on food and nutrition, endocrine disrupters, hormonal-dependent diseases, and biotechnologies, to a wider community of scientists and physicians as well as to a non-scientific audience. 

An important technical development of the PFG and STD experiments was introduced at the beginning of the 1990s the Diffusion Ordered Spectroscopy, that is DOSY.69 70 It provides a convenient way of displaying the molecular self-diffusion information in a bi-dimensional array, with the NMR spectrum in one dimension and the self-diffusion coefficient in the other. While the chemical-shift information is obtained by Fast Fourier Transformation (FFT) of the time domain data, the diffusion information is obtained by an Inverse Laplace Transformation (ILT) of the signal decay data. The goal of DOSY experiment is to separate species spectroscopically (not physically) present in a mixture of compounds for this reason, DOSY is also known as "NMR chromatography."... 

Karger (14) has made the only successful use of this technique thus far. His results for the water-13X system (Figures 4 and 5) are compared with the results of relaxation time measurements below. He has also made a detailed theoretical analysis (15) of this zeolite situation which indicates that in some cases diffusion information may be extracted even if... 

Information on how to build a Sionics sound suppressor (aka silencer) for the Ingram MIO and Mil appeared in PMA,Vol.2, No-1. That article featured machinist drawings so that a person with access to a lathe and other machine shop tools could turn out each suppressor part including the spiral diffusers. Information was pro-vided on how to construct suppressor tubes out of thin aluminum sheeting since the properly dimensioned tube blanks are difficult to obtain. Commercial tubing wholesalers usually have a minimum order requirement and local retail shops rarely have what you want in stock. 

The threshold volume fraction, c, depends not only on the spatial dimensionality but also on extrinsic factors. For a 3D, continuous, random mixture, d is ideally 15% values for other dimensions are listed in Table 7. However, c may be easily affected by the state of dispersion, size, shape, orientation, and distribution of the conductive phase. Therefore, it is best determined empirically. Finally, the prefactor o depends on details of ionic and molecular interactions and can only be computed from specific microscopic models. The important feature to be appreciated here is that the topological and geometrical information of the cluster connectivity is lumped together in the (c-c ) factor whereas the microscopic diffusion information and various interactions are contained in the prefactor o. ... 

Diffusion Data, 1967-1973, vols. 1-7, Diffusion Information Center, Cleveland, Ohio. 

Figure 9. Borehole temperature versus depth (Cuffey and Clow 1997), and 5 0 of ice versus age (Grootes and Stuiver 1997), for GISP2, central Greenland. Approximate correspondence between the imprints of prominent climate events in these records are indicated by tie lines the diffusive information loss from heat flow is evident in the greater smoothness of the borehole-temperature record. The borehole record is quite smooth, but appears slightly rough because of the plotting package used.

Diffusive information loss limits resolution of borehole-derived paleotemperatures. A borehole temperature profile from central Greenland reveals information about the previous day, the previous year, the previous decade, the Little Ice Age of one to a few centuries ago, the warmth in the middle Holocene a few millennia ago, and the cold of the ice age centered about 20-30 thousand years ago (Alley and Koci 1990 Cuffey et al. 1992, 1994, 1995 Firestone 1995 Johnsen et al. 1995 Cuffey and Clow 1997 Dahl-Jensen et al. 1998). 

Substantial effort is required to measure the He diffusivity parameters in a given phase and to determine how those parameters vary with mineral characteristics such as grain size and shape, chemical composition, and defect and/or radiation damage density. Only apatite has been studied in detail, but limited He diffusivity information is available on other minerals as well, as discussed below. 

An average molecular weight can be determined by combining intrinsic viscosity and translational diffusion information in the Mandelkern-Flory relationship... 

Since most of the relevant parameters are not yet known for those systems on which boundary diffusion information exists a quantitative comparison with space charge theory is not yet possible. 

It has recently become popular to present results in a 2D manner, with spectral information on the x and z axes (frequency and intensity, respectively) and diffusion information on the y axis. This display mode for FT-PGSE results has been named DOSY (diffusion-ordered spectroscopy). Its introduction... 

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