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Subject characterization

Some tests, like lather volume, involved objective laboratory measurements. For example, a technician might produce lather by a prescribed washing procedure intended to consistently reproduce the same motions, and this lather volume would be measured in a graduated cylinder to give an objective measure [12], Other tests, like wet bar feel, required the subjective measurement of trained assessors. For example, the wet feel of a bar would be subjectively characterized as draggy or slippery by an expert panel of evaluators [13]. [Pg.280]

Each sample should be evaluated for sperm viability (percent viable sperm moving at the time of e) mination) as well as sperm motility (subjective characterization of purposeful forward sperm progression of the majority of those viable sperm analyzed) within two hours after colledion, ideally by the same or equally qualified examiner. [Pg.1116]

There are two types of measurement errors, systematic and random. The former are due to an inherent bias in the measurement procedure, resulting in a consistent deviation of the experimental measurement from its true value. An experimenter s skill and experience provide the only means of consistently detecting and avoiding systematic errors. By contrast, random or statistical errors are assumed to result from a large number of small disturbances. Such errors tend to have simple distributions subject to statistical characterization. [Pg.96]

The ultrasonic array characterization purpose is a current subject of interest for presumably many UT teams. We hope that this paper will open a discussion, leading to a new standard. [Pg.826]

In recent years, advances in experimental capabilities have fueled a great deal of activity in the study of the electrified solid-liquid interface. This has been the subject of a recent workshop and review article [145] discussing structural characterization, interfacial dynamics and electrode materials. The field of surface chemistry has also received significant attention due to many surface-sensitive means to interrogate the molecular processes occurring at the electrode surface. Reviews by Hubbard [146, 147] and others [148] detail the progress. In this and the following section, we present only a brief summary of selected aspects of this field. [Pg.202]

Micellar structure has been a subject of much discussion [104]. Early proposals for spherical [159] and lamellar [160] micelles may both have merit. A schematic of a spherical micelle and a unilamellar vesicle is shown in Fig. Xni-11. In addition to the most common spherical micelles, scattering and microscopy experiments have shown the existence of rodlike [161, 162], disklike [163], threadlike [132] and even quadmple-helix [164] structures. Lattice models (see Fig. XIII-12) by Leermakers and Scheutjens have confirmed and characterized the properties of spherical and membrane like micelles [165]. Similar analyses exist for micelles formed by diblock copolymers in a selective solvent [166]. Other shapes proposed include ellipsoidal [167] and a sphere-to-cylinder transition [168]. Fluorescence depolarization and NMR studies both point to a rather fluid micellar core consistent with the disorder implied by Fig. Xm-12. [Pg.481]

The polarization P is given in tenns of E by the constitutive relation of the material. For the present discussion, we assume that the polarization P r) depends only on the field E evaluated at the same position r. This is the so-called dipole approximation. In later discussions, however, we will consider, in some specific cases, the contribution of a polarization that has a non-local spatial dependence on the optical field. Once we have augmented the system of equation B 1.5.16. equation B 1.5.17. equation B 1.5.18. equation B 1.5.19 and equation B 1.5.20 with the constitutive relation for the dependence of Pon E, we may solve for the radiation fields. This relation is generally characterized tlirough the use of linear and nonlinear susceptibility tensors, the subject to which we now turn. [Pg.1271]

In the first chapter, devoted to thiazole itself, specific emphasis has been given to the structure and mechanistic aspects of the reactivity of the molecule most of the theoretical methods and physical techniques available to date have been applied in the study of thiazole and its derivatives, and the results are discussed in detail The chapter devoted to methods of synthesis is especially detailed and traces the way for the preparation of any monocyclic thiazole derivative. Three chapters concern the non-tautomeric functional derivatives, and two are devoted to amino-, hydroxy- and mercaptothiazoles these chapters constitute the core of the book. All discussion of chemical properties is complemented by tables in which all the known derivatives are inventoried and characterized by their usual physical properties. This information should be of particular value to organic chemists in identifying natural or Synthetic thiazoles. Two brief chapters concern mesoionic thiazoles and selenazoles. Finally, an important chapter is devoted to cyanine dyes derived from thiazolium salts, completing some classical reviews on the subject and discussing recent developments in the studies of the reaction mechanisms involved in their synthesis. [Pg.599]

Step 3 Once formed the thiazolone derivative isomerizes to a more stable phenylthiohydantom (PTH) derivative which IS isolated and characterized thereby providing identification of the N terminal ammo acid The remainder of the peptide (formed m step 2) can be isolated and subjected to a second Edman degradation... [Pg.1134]

Studies aimed at characterizing the mechanisms of electrode reactions often make use of coulometry for determining the number of electrons involved in the reaction. To make such measurements a known amount of a pure compound is subject to a controlled-potential electrolysis. The coulombs of charge needed to complete the electrolysis are used to determine the value of n using Faraday s law (equation 11.23). [Pg.506]

Odors are characterized by quaUty and intensity. Descriptive quaUties such as sour, sweet, pungent, fishy, and spicy are commonly used. Intensity is deterrnined by how much the concentration of the odoriferous substance exceeds its detection threshold (the concentration at which most people can detect an odor). Odor intensity is approximately proportional to the logarithm of the concentration. However, several factors affect the abiUty of an individual to detect an odor the sensitivity of a subject s olfactory system, the presence of other masking odors, and olfactory fatigue (ie, reduced olfactory sensitivity during continued exposure to the odorous substance). In addition, the average person s sensitivity to odor decreases with age. [Pg.376]

The resistance to plastic flow can be schematically illustrated by dashpots with characteristic viscosities. The resistance to deformations within the elastic regions can be characterized by elastic springs and spring force constants. In real fibers, in contrast to ideal fibers, the mechanical behavior is best characterized by simultaneous elastic and plastic deformations. Materials that undergo simultaneous elastic and plastic effects are said to be viscoelastic. Several models describing viscoelasticity in terms of springs and dashpots in various series and parallel combinations have been proposed. The concepts of elasticity, plasticity, and viscoelasticity have been the subjects of several excellent reviews (21,22). [Pg.271]

The development of precise and reproducible methods of sensory analysis is prerequisite to the determination of what causes flavor, or the study of flavor chemistry. Knowing what chemical compounds are responsible for flavor allows the development of analytical techniques using chemistry rather than human subjects to characterize flavor (38,39). Routine analysis in most food production for the quaUty control of flavor is rare (40). Once standards for each flavor quaUty have been synthesized or isolated, they can also be used to train people to do more rigorous descriptive analyses. [Pg.3]

Estimates of the amount of natural gas available are made within the context of definitions and are subject to revision as definitions change, as additional information becomes available, as resources are consumed, or as undedyiag assumptions are altered. These definitions iaclude proved reserves where the resource is expected to be recoverable and marketable usiag known technology and prices probable reserves where a resource has been identified but not completely characterized and possible or potential gas where estimates are based on the available geological iaformation, historical trends, and previous successes. There are variations ia these definitions throughout the world. [Pg.168]

Antiwear premium hydrauHc fluids represent the largest volume of hydrauHc fluids used. Shortly after their introduction in 1960, a second product group was formulated, characterized by the same antiwear characteristics but having lower pour points and higher viscosity indexes. These were formulated for use in mobile and marine appHcations subject to temperature extremes. [Pg.262]

Odor perception and description are highly subjective in nature. Nevertheless, there is a generally agreed-upon odor vocabulary that is used to characterize individual ingredients and finished fragrances. Table 1 shows some commonly used odor descriptors grouped into five general classifications. [Pg.72]

Like mthenium, amines coordinated to osmium in higher oxidation states such as Os(IV) ate readily deprotonated, as in [Os(en) (NHCH2CH2NH2)] [111614-75-6], This complex is subject to oxidative dehydrogenation to form an imine complex (105). An unusual Os(IV) hydride, [OsH2(en)2] [57345-94-5] has been isolated and characterized. The complexes of aromatic heterocycHc amines such as pyridine, bipytidine, phenanthroline, and terpyridine ate similar to those of mthenium. Examples include [Os(bipy )3 [23648-06-8], [Os(bipy)2acac] [47691-08-7],... [Pg.178]

Class III Premarket Approval. Similar to a new dmg approval, a premarket approval grants the appHcant a Hcense to market a specific weU-characterized device. These devices are subject to the requirements of Section 515 of the Eood, Dmg, and Cosmetic Act. A post-amendment device is a device put ia commercial distribution after May 28, 1976. If it is not substantially equivalent to a preamendment device it is automatically ia Class 111, and a premarket approval appHcation (PMA) is required. The appHcation must iaclude reports of preclinical and clinical studies done ia support of claims of safety and efficacy as well as any labeling claims made for the device. Once the PMA is submitted, the PDA determines whether the appHcation iacludes the required information. If the PMA is suitable for scientific review, the PDA has 180 days from the filing date to approve or deny the appHcation. Polybutester, polydioxanone, polyglyconate, and ePTPE sutures are all regulated as Class 111 devices. [Pg.270]

The general criterion of chemical reaction equiUbria is the same as that for phase equiUbria, namely that the total Gibbs energy of a closed system be a minimum at constant, uniform T and P (eq. 212). If the T and P of a siagle-phase, chemically reactive system are constant, then the quantities capable of change are the mole numbers, n. The iadependentiy variable quantities are just the r reaction coordinates, and thus the equiUbrium state is characterized by the rnecessary derivative conditions (and subject to the material balance constraints of equation 235) where j = 1,11,.. ., r ... [Pg.501]


See other pages where Subject characterization is mentioned: [Pg.399]    [Pg.476]    [Pg.319]    [Pg.1701]    [Pg.399]    [Pg.476]    [Pg.319]    [Pg.1701]    [Pg.98]    [Pg.889]    [Pg.668]    [Pg.1263]    [Pg.2420]    [Pg.525]    [Pg.666]    [Pg.57]    [Pg.92]    [Pg.353]    [Pg.427]    [Pg.1]    [Pg.487]    [Pg.339]    [Pg.539]    [Pg.477]    [Pg.296]    [Pg.299]    [Pg.302]    [Pg.545]    [Pg.238]    [Pg.397]    [Pg.439]    [Pg.458]    [Pg.86]    [Pg.86]   
See also in sourсe #XX -- [ Pg.272 ]




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