Problems in use

There are problems in use of the frit nebulizer. Memory effects tend to be severe, and each sample needs to be followed by several wash-outs with clean solvent before the pores of the frit become free of residual sample. Biological samples frequently contain detergent-like materials, and... 

The principal problem in using fault trees is that for reasonably compHcated processes the analysis is most likely to produce a huge fault tree. Eault trees involving hundreds or even thousands of intermediate events are not uncommon. The effort involved in fault tree development can also be substantial, requiring several years. 

The relationship between what is recorded in a SSIMS spectrum and the chemical state of the surface is not as straightforward as in XPS and AES (Chap. 2). Because of the large number of molecular ions that occur in any SSIMS spectrum from a multi-component surface (e. g. during the study of a surface reaction), much chemical information is obviously available in SSIMS, potentially more than in XPS. The problem in using the information from a molecular ion lies in the uncertainty of knowing whether or not the molecule represents the surface composition. For some materials. 

Another serious effect occurs with liquids which are not in themselves solvents but which may wet the polymer surfaces. These facilitate relief of frozen-in stresses by surface cracking which can be a severe problem in using many injection and blow mouldings with specific chemicals. Examples of this are white spirit with polystyrene, carbon tetrachloride with polycarbonates and soaps and silicone oils with low molecular weight polyethylenes. 

The ZOE cement is easy to mix and a greater amount of powder can be incorporated into this cement (5 1 by mass) than any other, where even 4 1 by mass is unusual. Because the ZOE cement is sensitive to moisture it can be formulated to have a long working time under normal room conditions (23 °C, relative humidity 50 %) and a rapid set once placed in the warm and moist conditions of the mouth. This is a considerable clinical advantage, making it convenient to use. The cement can be used in a war pack for use on the battlefield. Nevertheless, sensitiveness to humidity can give rise to problems in use under tropical conditions. 

The main problem in using this method is the statistical error of the Compton profiles which calculates to... 

This spot-test reagent is now supplied water-wet since it has been found to be detonable and legally classifiable as an explosive. The editor has not heard of any problems in use. 

The editor would be surprised if it proved impossible to detonate this analytical reagent, the carboxylation product of 2,4-dinitrophenol, especially in contact with bases. There is no record of problems in use. 

The key problem in using Eq. (3.1) is the specification of p. We ask whether we can derive an expression for p. The velocity components u, v, and w, although random, are related through conservation of mass and momentum for the flow, that is, they are governed by the stochastic Navier-Stokes and continuity equations. In general, as we have noted, an exact solution for u, v, and w is unobtainable. We can, however, consider an idealized situation in which the statistical properties of u, v, and w are specified a priori. Then, in so doing, we wish to see if we can obatin an exact solution of Eq. (2.4) from which p can be obtained through Eq. (2.6). 

In the case of thicknesses larger than mentioned above the intensities must be calculated according to the more general many-beam theory. The calculation should include summation over different groups of crystals having a certain distributions of thickness and orientation. A method based on the matrix formulation of the many-beam theory was developed for partly-oriented thin films and have been successfully applied samples [2]. The main problem in using direct many-beam calculation is to find the distribution functions for size and orientation of the microcrystals. However, it is not always possible to refine these functions in the process of intensity adjustment. Additional investigation of the micro-structure by electron microscopy is very helpful in such case. 

There are several problems in using the TEF approach in the risk assessment of PAH in food. The use of the TEF approach requires that the compounds in question exert the toxicological effect by the same mechanism of action, such as is the case for the polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, which act through binding to the Ah-receptor. Although a number of... 

A significant problem in using the uranium-lead system for age dating is that the system is relatively easily disturbed. However, George Wetherill showed that by using both the... 

No object can radiate more energy than can a blackbody at the same temperature, because a blackbody in equilibrium with a radiation field at temperature T radiates exacdy as much energy as it absorbs. Any object exhibiting surface reflection must have emissivity of less than 1. Pyrometers are usually calibrated with respect to blackbodies. This can cause a serious problem in use. The emissivities of some common materials are listed in Table 4. 

Some arrays used in proteomics contain antibodies covalently bound onto the array surface for immobilization. Then these antibodies capture corresponding antigens from a complex mixture. Afterwards, a series of analysis are carried out. For instance, bound receptors can reveal ligands. With this information in hand, binding domains for protein-protein interactions can be detected. The main problem in using microarray methods for proteomics is that protein molecules must show folding with the array in the correct conformation during the preparation and incubation. Otherwise, protein-protein interactions do not take place. 

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