Potential well, secondary

For HTS applications, the incubation period required to generate adequate fluorescent signal above background is usually about 2 to 4 hr, depending on the number of cells per well and their metabolic activity. Although longer incubation periods have been used, caution should be observed to avoid artifacts caused by the potential for secondary chemical reduction of resorulin into a colorless non-fluorescent compound and the known toxic effects of resazurin exposure to cells. 

Furthermore, secondary bond distances vary widely, even among chemically equivalent bonds in the same complex (e.g., from 264.0pm to 292.6pm for Ag-Cl contacts in Ag[CBiiH6Cl6] " ). One wonders whether these differences signify any difference in secondary bond strength or bond order, or whether secondary bonding involves such a shallow potential well that the differences merely represent variations in what is needed to achieve optimal solid-state packing. 

The theory of two potential wells of nearly equal depth has been used to explain secondary relaxations in amorphous polymers. Recent results by L. C. E. Struik led to the result... 

Cardiac glycosides found in plants, some insects and in the skin of toads (Bufonidae) are potent and well-known inhibitors of Na+/K+-ATPase. Also few alkaloids, such as harmaline, nitidine, sanguinarine, capsaicine, cassaine, and solenopsine (from ants) exhibit Na+/K+-ATPase inhibition, which interferes with the maintainance of the membrane potential and secondary active transport systems. 

In the absence or weakness of non-electrostatic stability factors and at excess electrolyte concentration above a threshold, possibilities of contactless flotation should be checked. The particle attachment can take place through heterocoagulation in the secondary minimum of the total-interactions energy curve, if its depth is deep enough. High electrolyte concentration, suppressing electrostatic repulsion, weakness of non-electrostatic factors of stability and the presence of attraction forces caused by molecular attraction or action of the adsorbed surfactant are favourable prerequisites for the appearance of a sufficiently deep potential well. 

In the majority of incidents, basic victim decontamination as outlined above will substantially reduce or eliminate the potential for secondary contamination of downstream personnel or equipment. Procedures for cleaning equipment are contaminant-specific and depend on the risk of chemical persistence as well as toxicity. 

The possibility to introduce genes into plants using the Agrobacterium technology as well as particle bombardment has increased the potential for secondary metabolites production in plant cultures by the exploitation and improvement of their own biosynthetic capacities [9, 79]. It is well known that the yield of tropane alkaloids is low for a commercial production. For this reason, is desirable to increase production of these alkaloids in plant species [32]. Numerous works have focused on the genetic engineering of the tropane alkaloids pathway according to the interest in these compounds. 

Thus, ETD lends the capabilities of ECD to linear ion trap mass spectrometers. The individual steps involved in the operation of an LTQ instrument in ETD mode (Fig. 9.39) are injection of multiply protonated peptides as delivered by an ESI source application of a DC offset to store these ions in the front section of the LIT followed by injection of reagent anions from the Cl source into the center of the LIT. Then all but the peptide precursor ions and the electron-donor reagent ions are ejecteeL Next the DC potential well is switched off and a secondary RF voltage is applied to the end lens plates of the LIT causing positive and negative ion populations to mix and react. The reaction period is ended by axial ejection of reagent anions while positive product ions are retained in the center section of the LIT. Finally, mass-selective radial ejection as usual yields the ETD spectrum [160]. The attractive ETD technique has also been implemented on LITs with axial ejection [144,166] and on LIT-orbitrap hybrids [167-169]. 

While with-in the mobile x-ray system, the waste in the sampler, is contained within a replaceable (and disposable) polyvinyl chloride (PVC) sleeve with a wall thickness of approximately 0.2-inches and a sealed bottom. It was anticipated that the PVC tube or sleeve would, with use, become highly contaminated with waste residues which drip of fall-off the sampler. The sleeve is coated with a conductive coating to prevent static electricity buildup . There are no sources of ignition in this sealed spare. The sampler (and waste) is coupling which includes a positive pressure gasket. This barrier is further isolated by a second barrier consisting of an epoxy coated aluminum sleeve also sealed-off from the main x-ray cabinet and PVC sleeve. There are also no potential sources of ignition in this isolated secondary space as well. 

In the latter twentieth century, spent automotive catalysts have emerged as a significant potential source of secondary Pt, Pd, and Rh. In North America, it has been estimated that 15.5 metric tons per year of PGM from automotive catalysts are available for recycling (22). However, the low PGM loading on such catalysts and the nature of the ceramic monoliths used have required the development of specialized recovery techniques as well as the estabhshment of an infrastmcture of collection centers. These factors have slowed the development of an automotive catalyst recycling iadustry. 

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