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Johnson 6 well

Laurent C, Johnson-Wells G. Hellstrom S, Engstrom-Laurent A, Wells AF. Localization of hyaluronan in various muscular tissues. A morphological study m the rat. Cell Ti.ssue Res. 1991 263 201-5... [Pg.139]

The isobaric specific heat for a petroleum fraction is estimated by a correlation attributed to Watson and Nelson in 1933, which was used again by. Johnson and Grayson in 1961 as well as by Lee and Kesler in 1975. This relation is valid at low pressures i... [Pg.121]

Synthesis The early stages of this route are a well established method to make benzocyclohexanones the later stages are adapted from Johnson s Conessme synthesis ( J. [Pg.84]

The achiral triene chain of (a//-rrans-)-3-demethyl-famesic ester as well as its (6-cis-)-isoiner cyclize in the presence of acids to give the decalol derivative with four chirai centres whose relative configuration is well defined (P.A. Stadler, 1957 A. Escherunoser, 1959 W.S. Johnson, 1968, 1976). A monocyclic diene is formed as an intermediate (G. Stork, 1955). With more complicated 1,5-polyenes, such as squalene, oily mixtures of various cycliz-ation products are obtained. The 18,19-glycol of squalene 2,3-oxide, however, cyclized in modest yield with picric acid catalysis to give a complex tetracyclic natural product with nine chiral centres. Picric acid acts as a protic acid of medium strength whose conjugated base is non-nucleophilic. Such acids activate oxygen functions selectively (K.B. Sharpless, 1970). [Pg.91]

In an amorphous material, the aUoy, when heated to a constant isothermal temperature and maintained there, shows a dsc trace as in Figure 10 (74). This trace is not a characteristic of microcrystalline growth, but rather can be well described by an isothermal nucleation and growth process based on the Johnson-Mehl-Avrami (JMA) transformation theory (75). The transformed volume fraction at time /can be written as... [Pg.339]

Semiconductor devices ate affected by three kinds of noise. Thermal or Johnson noise is a consequence of the equihbtium between a resistance and its surrounding radiation field. It results in a mean-square noise voltage which is proportional to resistance and temperature. Shot noise, which is the principal noise component in most semiconductor devices, is caused by the random passage of individual electrons through a semiconductor junction. Thermal and shot noise ate both called white noise since their noise power is frequency-independent at low and intermediate frequencies. This is unlike flicker or ///noise which is most troublesome at lower frequencies because its noise power is approximately proportional to /// In MOSFETs there is a strong correlation between ///noise and the charging and discharging of surface states or traps. Nevertheless, the universal nature of ///noise in various materials and at phase transitions is not well understood. [Pg.346]

C. D. Johnson, The Hammett Equation, Camhndge University Press, Cambridge, 1973. P. R. Wells, Linear Free Energy Relationships, Academic Press, New bik, 1968. [Pg.249]

Perhaps the most significant complication in the interpretation of nanoscale adhesion and mechanical properties measurements is the fact that the contact sizes are below the optical limit ( 1 t,im). Macroscopic adhesion studies and mechanical property measurements often rely on optical observations of the contact, and many of the contact mechanics models are formulated around direct measurement of the contact area or radius as a function of experimentally controlled parameters, such as load or displacement. In studies of colloids, scanning electron microscopy (SEM) has been used to view particle/surface contact sizes from the side to measure contact radius [3]. However, such a configuration is not easily employed in AFM and nanoindentation studies, and undesirable surface interactions from charging or contamination may arise. For adhesion studies (e.g. Johnson-Kendall-Roberts (JKR) [4] and probe-tack tests [5,6]), the probe/sample contact area is monitored as a function of load or displacement. This allows evaluation of load/area or even stress/strain response [7] as well as comparison to and development of contact mechanics theories. Area measurements are also important in traditional indentation experiments, where hardness is determined by measuring the residual contact area of the deformation optically [8J. For micro- and nanoscale studies, the dimensions of both the contact and residual deformation (if any) are below the optical limit. [Pg.194]

Additional suggested resources for the reader include introductory articles on scanning probe techniques for materials properties measurement [82,83J. A comprehensive manual describing various surface preparation techniques, experimental procedures and instrumentation is also a good resource [84J, although the more recent modulation based techniques are not covered. Key textbooks include Johnson s on contact mechanics [51J and Israelachvili s on surface forces [18J, as well as a treatment of JKR/DMT issues by Maugis [85J. [Pg.206]

Johnson Division-Universal Oil Products Company, Groundwater and Wells, St. Paul, Minnesota, 1972, p. 177. [Pg.129]

Obviously, the mean-field treatment of the attraetive van der Waals inter-aetion results in negleet of the influenee of the interpartiele eorrelations on as well as the influenee of attraetive forees on assoeiation effeets (ef. the definition of Eq. (78)). To obtain a more adequate approximation, Johnson and Gubbins (see, e.g., [114]), have developed an aeeurate equation of state for assoeiating Lennard-Jones fluids, or more preeisely for the following nonassoeiative potential... [Pg.199]

One is the concerted decomposition of a dioxetanone structure that is proposed for the chemiluminescence and bioluminescence of both firefly luciferin (Hopkins et al., 1967 McCapra et al., 1968 Shimomura et al., 1977) and Cypridina luciferin (McCapra and Chang, 1967 Shimomura and Johnson, 1971). The other is the linear decomposition mechanism that has been proposed for the bioluminescence reaction of fireflies by DeLuca and Dempsey (1970), but not substantiated. In the case of the Oplopborus bioluminescence, investigation of the reaction pathway by 180-labeling experiments has shown that one O atom of the product CO2 derives from molecular oxygen, indicating that the dioxetanone pathway takes place in this bioluminescence system as well (Shimomura et al., 1978). It appears that the involvement of a dioxetane intermediate is quite widespread in bioluminescence. [Pg.87]

NSAIDs can induce a number of other adverse reactions, including bleeding disorders, anemia, thrombocytopenia, erythema nodosum, erythema multiforme, fixed drug eruptions, toxic epidermal necrolysis, Stevens-Johnson syndrome, leukocytocla-sitc vasculitis, recurrent fever with exanthema and, of course, the well-known gastric cytotoxicity. [Pg.177]

Johnson et al. [186] measured diffusion of fluorescein-labeled macromolecules in agarose gels. Their data agreed well with Eq. (85), which combined the hydrodynamic effects with the steric hindrance factors. Gibbs and Johnson [131] measured diffusion of proteins and smaller molecules in polyacrylamide gels using pulsed-field gradient NMR methods and found their data to fit the stretched exponential form... [Pg.584]

The previous sort of question is relevant to the matter of computer use and the issue of privacy. In fact, computer use may have altered the way we think and should think of privacy. Before the advent and prevalence of computers, intrusions into an individual s privacy were largely time- and place dependent. The intrusion could be done but only on a small scale. As Johnson [15] notes, however, computers have changed the nature of intrusion into privacy as well as the scale of intrusion into privacy. The result is a demand to rethink privacy and rethink the framework of applied ethics, especially because the scale of intrusion may change the qualitative nature of the offense. [Pg.719]

Johnson [17] identifies several topics related to liability, and she offers an important distinction as well. Among the topics related to liability and computer use in general are legal liability, the duty of honesty, the nature of contracts, misrepresentation, express and implied warranties, and negligence [17]. The relevant distinction concerns the nature of software as either a product or a service. Many of these topics hold little interest for the ethicist investigating computer ethics. For instance, legal liability is less important to philosophy than to jurisprudence. [Pg.721]

Johnson R, J Pankow, D Bender, C Price, J Zogorski (2000) MTBE to what extent will past releases contaminate community water supply wells Environ Sci Technol 34 210A-217A. [Pg.582]

Using this system, SC Johnson scores both raw materials and formulated products, tracks the score of all raw material purchases and measures the overall percentage of materials that fall into each rating category, that is considered Best or RUM . The scores are used to set company goals, as well as to reward the formulators and chemists who use the system to improve the environmental and human health profiles of individual products and product lines. [Pg.295]

This chapter, however, does not deal with above-mentioned reactions of sulfoxides. Rather it is limited to asymmetric synthesis using a-sulfinyl carbanions and -unsaturated sulfoxides, specifically in which the stereogenic sulfoxide sulfur atom is enantiomerically pure. Therefore reactions of racemic sulfoxides are for the most part excluded from this review. For more general discussions, the reader is referred to other chapters in this volume and to other reviews on the chemistry of sulfoxides. Especially useful are the reviews by Johnson and Sharp and by Mislow in the late 1960s and by Oae and by Nudelman as well as a book by Block . A review by Cinquini, Cozzi and Montanari" through mid-1983 summarizes the chemistry and stereochemistry of optically active sulfoxides. This chapter emphasizes results reported from 1984 through mid-1986. [Pg.824]

Sediment may be added by bulk mixing via imbricate thnisting (Bebout and Barton 2002), dehydration (Class et al. 2000), or melting (Johnson and Plank 1999). The latter two may differ in their P-T conditions and, therefore, residual mineralogy as well as relevant partition coefficients. In general, fluids are less effective transport agents than melts (i.e., trace elements are more soluble in melt than in pure water or even brine), but fluid/solid partitioning can fractionate some elements, notably Ba-Th and U-Th, more than melt/solid. However, as pressure increases, the distinction between fluid and melt decreases as their mutual solubility increases and they approach a critical end-point. [Pg.271]


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See also in sourсe #XX -- [ Pg.245 , Pg.407 ]




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