From Solid Media

Using plants for nanoparticle synthesis can be advantageous over other biological processes because it eliminates the elaborate process of maintaining cell cultures and can also be suitably scaled up for large-scale synthesis of nanoparticles [24], Gardea-Torresdey et al. [25,26] demonstrated the synthesis of gold and silver nanoparticles within live alfalfa plants from solid media. 

Development of a clinically comprehensive database and a simple procedure for identification of molds from solid media by matrix-assisted laser desorption ionization-time of flight mass spectrometry. J. Clin. Microbiol, 51, 828-834. 

Agar occurs as a cell-wall constituent of the red marine algae Rho ophyceae, from which it is extracted by hot water, and marketed as a dry powder, flakes, or strips. It dissolves in hot water and sets on cooling to a jelly at a concentration as low as 0-5%. Its chief uses are as a solid medium for cultivating micro-organisms, as a thickener, emulsion stabilizer in the food industry and as a laxative. 

Dodonoy A I, Mashkova E S and Molchanov V A 1989 Medium-energy ion scattering by solid surfaces. Ill ejection of fast recoil atoms from solids under ion bombardment Rad. Eff. Def Sol. 110 227-341... 

Mashkova E S and Molchanov V A 1985 Medium-Energy Ion Reflection From Solids (Amsterdam North-Holland)... 

Liquid diops, suspended in a continuous liquid medium, separate according to the same laws as solid paiticles. Aftei reaching a boundary, these drops coalesce to form a second continuous phase separated from the medium by an interface that may be well- or ill-defined. The discharge of these separated layers is controlled by the presence of dams in the flow paths of the phases. The relative radii of these dams can be shown by simple hydrostatic considerations to determine the radius of the interface between the two separated layers. The radius is defined by... 

This section describes equipment for heat transfer to or from solids by the indirect mode. Such equipment is so constructed that the solids load (burden) is separated from the heat-carrier medium by a wall the two phases are never in direct contact. Heat transfer is by conduction based on diffusion laws. Equipment in which the phases are in direct contact is covered in other sections of this Handbook, principally in Sec. 20. 

The hydrostatic pressure varies from a maximum at the point where suspension enters the cake, to zero where liquid is expelled from the medium consequently, at any point in the cake the two are complementary. That is, the sum of the hydrostatic and compression pressures on the solids always equals the total hydrostatic pressure at the face of the cake. Thus, the compression pressure acting on the solids varies from zero at the face of the cake to a maximum at the filter medium. 

The flotation process was developed in the mining and coal processing industries as a way of separating suspended solids from a medium such as water. As noted above, the flotation process has found uses in other fields, such as wastewater treatment. The process introduces fine air bubbles into the mixture, so that the air bubbles attach to the particles, and lift them to the surface. 

A heat exchanger is a device that transfers heat from one medium to another the medium may be a solid, liquid, or gas. Some of the most complex engineering design problems relate to heat exchangers. 

In most cases diazonium salts are not isolated, but are converted into products by reactions that can be carried out in situ. Moreover, it is actually recommended not to isolate these salts, not even for purification purposes, as many of them have a tendency to explode. In addition, the high solubility of most diazonium salts in water makes precipitation from this medium difficult. Therefore, to obtain solid diazonium salts the recommended method for many decades was to carry out diazotizations in ethanol followed by precipitation with ether. As inorganic salts of nitrous acid are scarely soluble in ethanol, Knoevenagel recommended alkyl nitrites (ethyl or isopentyl nitrite) as diazotization reagents as long ago as 1890. Various other solvents have subsequently been used for diazotizations with alkyl nitrites (see Saunders and Allen, 1985, p. 23 ff.), but as a method for obtaining solid diazonium salts this has been superseded by the isolation of diazonium tetrafluoroborates and, to a lesser degree, of hexafluorophosphates. 

Solid disinfectants may be evaluated in vitro by applying them to suitable test organisms growing on solid medium. Discs may be cut from the agar and subcultured, observing the usual precautions. 

Rationale. Microorganisms were isolated from soil and screened for toxin production according to the scheme in Figure 1. Some of the organisms causing strong inhibition on solid medium were tested for toxin production in liquid medium. Liquid culture will be required to obtain large amounts of material for commercial production of herbicides, however, the ability to produce toxins on solid medium does not necessarily imply toxin production in broth (34). Cyclo-heximide, a phytotoxic but relatively nonspecific antibiotic with little value as a herbicide, is produced by many actinomycetes. Liquid cultures were tested for cycloheximide to determine whether it caused the observed toxicity. 

In many diffusion problems of practical importance in the pharmaceutical sciences, such as intrinsic dissolution studies and drug release from solid dosage forms, the medium under consideration is not at rest. In addition to concentration changes due to diffusion, there are concentration changes by convection. External forces, such as pressure gradients and temperature differences, can cause convective flows. Although convection can also be caused by diffusion itself, our discussion is limited to convection caused by external forces, since convection produced by diffusion is negligible (less than 10%) for most pharmaceutical problems. 

As for the refracted beam, the change in its direction is due to a change in the velocity of light as it passes from one medium to another. When a beam of light passes from a fast medium (such as a vacuum or air) to a slower medium (e.g., a crystalline solid), the change in velocity causes the beam to bend toward the normal (line perpendicular) to the boundary between the two media (see Fig. 18). The index of refraction, also known as the refractive index, the numerical value of the ratio between the speed of light in a vacuum to the speed of light in a material, provides... 

The simplest technique is the use of the 96-well collection plate format (analogous to the format used in SPE) in conjunction with a liquid handling robotic system it follows the same principle as bulk scale LLE. However, immobilization of the aqueous plasma sample on an inert solid support medium packed in a cartridge or in the individual wells of a 96-well plate and percolating a water-immiscible organic solvent to extract the analyte from this medium evoked significant enthusiasm from the pharmaceutical industry. 

Because of the requirements of insolubility in water, in organic solvents and in the medium that it is being used to colour, the application processes for using pigments are quite different from those for dyes. Coloration with pigments is essentially a process of dispersion of solid particles of the pigment in a semi-solid medium. 

In gases (atomic or ionic) the electronic energy levels of free atoms are narrow, since they are diluted systems and perturbation by the surroundings is very weak. An important fact derived from the discrete nature of the electronic levels in a gas is the high monochromaticity of the laser lines in this type of laser, compared to that of solid-medium based lasers. The high degree of coherence achievable with gas lasers is also a characteristic feature related to the narrow linewidth. 

In the subsurface, kerosene volatilization is controlled by the physical and chemical properties of the solid phase and by the water content. Porosity is a major factor in defining the volatilization process. Galin et al. (1990) reported an experiment where neat kerosene at the saturation retention value was recovered from coarse, medium, and fine sands after 1, 5, and 14 days of incubation. The porosity of the sands decreased from coarse to fine. Figure 8.9 presents gas chromatographs obtained after kerosene volatilization. Note the loss of the more volatile hydrocarbons by evaporation in all sands 14 days after application and the lack of resemblance to the original kerosene. It is clear that the pore size of the sands affected the chemical composition of the remaining kerosene. For example, the fractions disap-... 

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