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Subject improper

Sources of Error. pH electrodes are subject to fewer iaterfereaces and other types of error than most potentiometric ionic-activity sensors, ie, ion-selective electrodes (see Electro analytical techniques). However, pH electrodes must be used with an awareness of their particular response characteristics, as weU as the potential sources of error that may affect other components of the measurement system, especially the reference electrode. Several common causes of measurement problems are electrode iaterferences and/or fouling of the pH sensor, sample matrix effects, reference electrode iastabiHty, and improper caHbration of the measurement system (12). [Pg.465]

Systematic Measurement Error Fourth, measurements are subject to unknown systematic errors. These result from worn instruments (e.g., eroded orifice plates, improper sampling, and other causes). While many of these might be identifiable, others require confidence in all other measurements and, occasionally, the model in order to identify and evaluate. Therefore, many systematic errors go unnoticed. [Pg.2550]

The Oil Pollution Act of 1961 was primarily concerned witli tlie regulation of the deliberate discharge of oil or oil wastes into Uie water. As a result of Uiis act, Uie owners of transport sliips were to take precautions to minimize Ute effect of pollution. Oily ballast water separators were required on ships, and owners Imd to maintain oil record books. Violators of Uie Oil Pollution Act were subject to fines of not more than 1,000 for improper record keeping. [Pg.33]

The age-old problem of predicting what will happen to any material after it is subjected to service also exists with plastics. Different data on plastics are available, but typical of so-called progress, there is never sufficient or adequate useful information to predict the service life of products being designed. It is suggested that rather than assume that a lack of data exists, one should determine what is logically available and apply it most efficiently. A potential example of improper design with plastics concerns toys. [Pg.101]

Improper sampling can introduce errors originating at the surface (8.7) because x-ray emission spectrography operates only on a surface layer of critical thickness (6.4). Powders are particularly subject to errors that result from segregation and lack of uniformity in general (7.8, 7.15). Nonuniform residues from the evaporation of solutions can be troublesome. [Pg.288]

Dmg products that have been subjected to improper storage conditions including extremes in temperature, humidity, smoke, fumes, pressure, age, 74... [Pg.74]

Is there, then, an improper axis S(Note that if n > 2, the n-fold rotation axis C is by convention taken to be the vertical (z) axis). You have replied that there is indeed an axis Sjn. However, are there other binary axes perpendicular to the If not, the symmetry of your molecule is described by one of the groups Ja, (Note that if n is odd, there is a center of inversion). However, this result is subject to doubt, as there are very few molecules of symmetry J ... [Pg.401]

Acceptance testing of fusible link fire dampers should always include a random sample actual fusible link (melting) test of the installed assembly that causes the damper to close. Many times an improperly installed damper will not close correctly and the shutter louvers become hung up or twisted. An alternative sometimes available is a link assembly that can be temporary installed that is easily cut by a pair of clippers. The fusible link melting temperature can then be tested separately at a convenient location without subjecting the installation heat or flames for testing purposes. [Pg.173]

Precautions should be taken to avoid flashbacks. Flashbacks result from improperly mixed fuel and air, such as when the flow regulators on the instrument are improperly set or when air is drawn back through the drain line of the premix burner. Manuals supplied with the instruments when they are purchased give more detailed information on the subject of safety. [Pg.258]

To collect a representative sample forms a vital aspect of analytical chemistry, because the samples subjected to analysis are assumed to be perfectly homogeneous and truly representative. Thus, sampling may be considered as the most critical aspect of analysis. In other words, the accuracy and significance of measurements may be solely limited by the sampling process. Unless and until the sampling process is performed properly, it may give rise to a possible weak link in the interpretation of the analytical results. For instance, the improper... [Pg.6]

With regard to fundamental principles I have shown the relation as well as the differences between the stereochemical treatment of low molecular weight and that of macromolecular compounds. If some confusion has resulted in the past, it is due to the improper use of concepts and of methods outside their proper held. Macromolecular stereochemistry can be subjected to physico-math-ematical approaches based on concepts of system and structure and on topological principles. Interesting developments in this regard were recently published by Danusso and co-workers (411-413). [Pg.94]

The sample subjected to factor changing its original content such as extended transportation time, incubated at high temperature, or improper handling... [Pg.743]

The energy dissipation of a system containing free charges subjected to electric fields Is well known but this Indicates a non-equilibrium situation and as a result a thermodyanmlc description of the FDE Is Impossible. Within the framework of interionic attraction theory Onsager was able to derive the effect of an electric field on the Ionic dissociation from the transport properties of the Ions In the combined coulomb and external fields (2). It is not improper to mention here the notorious mathematical difficulty of Onsager s paper on the second Wien effect. [Pg.155]

Quicklime, therefore, does not attract air when in its most ordinary form, hut is capable of being joined to one particular species only, which is dispersed through the atmosphere, either in the shape of an exceedingly subtile powder, or more probably in that of an elastic fluid. To this I have given the name of fixed air, and perhaps very improperly but I thought it better to use a word already familiar in philosophy than to invent a new name, before we be more fully acquainted with the nature and properties of this substance, which will probably be the subject of my future inquiry. 4... [Pg.466]

Nutrient deficiencies are difficult to research in humans because the test subject would have to be removed from that nutrient for an extended period of time, possibly to leading a state of starvation. Thus, clinical deficiencies of n-3 fatty acids have been reported by only two researchers. Both of these studies involved one patient each and different clinical symptoms were observed in the patient prior to ALA supplementation (Bjerve et al., 1988 Holman et al., 1982). Thus, our knowledge of symptoms of ALA deficiency is not complete. Furthermore, a complete removal of ALA may not be required for the manifestation of clinical symptoms related to an improper balance between ALA and other fatty acids in the diet. Many of these symptoms can be related to the overproduction of the proinflammatory eicosanoids, synthesized from fatty acids other than ALA, resulting in heart disease and cancer (Morris, 2003b). [Pg.21]


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See also in sourсe #XX -- [ Pg.147 ]




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