Buck studies

Pemberton and Buck " studied the adsorption on a silver electrode of diphenylthiocarbazone anion (HDz ), a dye with its absorption maximum at 470 nm. An ORC was not carried out. Again, the enhancement was not evaluated. However, if one compares the surface spectra obtained, to those reported for a gold electrode using 488-nm light, it is immediately clear that the Raman scattering is hardly surface enhanced at all on silver, as it is not, at least at this excitation, at gold. 

Following the Longuet-Higgins—Salem approach, Buck studied the tendency of aromatic monocyclic compounds to bond alternation with increasing ring size. He used the Huckel model with variable P for the 7T electrons and a Morse potential for the o electrons. His distortion energies show that the o system resists distortion and the tt system favors distortions from D h to D i2)h symmetry in C H annulenes with 77 = 6, 8, 10, 12, 14, 16. The symmetry of the HOMO and LUMO is used to predict whether the C30H30 bond alternation due to the tt electrons should occur. It was subsequently shownthat this method can also be applied to the characterization of antiaromatic polycycles. 

The zero current switching (ZCS) quasi-resonant (QR) switching power supply forces the current through the power switch to be sinusoidal. The transistor is always switched when the current through the power switch is zero. To understand the operation of a ZCS QR switching power supply, it is best to study in detail the operation of its most elementary topology—the ZCS QR buck converter (and its waveforms) as seen in Figure 4-10. 

Woodson, K, J Gillespie, J Hanson, M Emmert-Buck, JM Phillips et al. 2004. Heterogeneous gene methyla-tion patterns among pre-invasive and cancerous lesions of the prostate a histopathologic study of whole mount prostate specimens. Prostate 60(1) 25-31. 

The few examples of deliberate investigation of dynamic processes as reflected by compression/expansion hysteresis have involved monolayers of fatty acids (Munden and Swarbrick, 1973 Munden et al., 1969), lecithins (Bienkowski and Skolnick, 1974 Cook and Webb, 1966), polymer films (Townsend and Buck, 1988) and monolayers of fatty acids and their sodium sulfate salts on aqueous subphases of alkanolamines (Rosano et al., 1971). A few of these studies determined the amount of hysteresis as a function of the rate of compression and expansion. However, no quantitative analysis of the results was attempted. Historically, dynamic surface tension has been used to study the dynamic response of lung phosphatidylcholine surfactant monolayers to a sinusoidal compression/expansion rate in order to mimic the mechanical contraction and expansion of the lungs. 

I. Dauster, M. A. Suhm, U. Buck, and T. Zeuch, Experimental and theoretical study of the microsolvation of sodium atoms in methanol clusters Differences and similarities to sodium water and sodium ammonia. Phys. Chem. Chem. Phys. 10, 83 95 (2008). 

M. Buck, Trifluoroethanol and colleagues cosolvents come of age. recent studies with peptides and proteins. Q. Rev. Biophys. 31, 297 355 (1998). 

C. L. Poglitsch and N. L. Thompson, Substrate-supported planar membranes containing murine antibody Fc receptors A total internal reflection fluorescence microscopy study, in Biosensor Technology, Fundamentals and Applications (R. P. Buck, W. E. Hatfield, M. Umafiia, and E. F. Bowden, eds.), pp. 375-382, Marcel Dekker, New York (1990). 

Although there are no data from human studies that indicate that hepatic effects occur in humans exposed to heptachlor, the animal studies indicate that the liver is a target organ for this chemical and is more sensitive to low doses than the neurological system. Decreased glycogen, increased cholesterol, GOT, and AP enzyme levels, and increased liver weight were reported in mice fed heptachlor at 0.5 mg/kg/day. In contrast, neurological effects such as convulsions were observed in a cow fed 2.5 mg/kg/day heptachlor daily for 15 days (Buck et al. 1959). Increased liver enzymes could indicate exposure to heptachlor, but this would not be a marker specific to this chemical. Refer to Section 2.2 for a detailed discussion of the effects caused by heptachlor and heptachlor epoxide. 

Buck WB, Radeleff RD, Jackson JB, et al. 1959. Oral toxicity studies with heptachlor and heptachlor epoxide in young calves. J Econ Entomo 52(6) 1127-1129. 

Recent smooth muscle constrictor studies performed in our laboratory in collaboration with Dr. Marion Buck at Yale University have yielded interesting results. Various fractions were first tested in human volunteers for bronchoconstrictor activity and then bioassayed by the rat stomach strip isolated organ bath technique. The fractions demonstrating constrictor activity in man correlated precisely with the constrictor activity in the isolated organ bath. This effect was antagonized by methysergide (6 ). 

Example Case Study—More Bang for the Buck Getting the Most from Accident Investigations... 

Previous review articles on spent nuclear fuel and UO2 corrosion have dealt with the details of uraninite alteration (Finch Ewing 1992), spent fuel corrosion in oxidizing and reducing environments (Johnson Shoesmith 1988 Wronkiewicz Buck 1999 Shoesmith 2000), and the evolution of spent fuel microstructure (Poinssot et al. 2002). In this Chapter, the behaviour of three important radionuclides (237Np, 99Tc, and 239Pu) is examined with examples of studies from spent fuel corrosion tests to illustrate the potential geochemical behaviour of these radionuclides. 

Mamelak M, Adele C, Buck L, et al. A comparative study of the effects of brotizolam and flurazepam on sleep and performance in the elderly. J Clin Psychopharmacol 1989 9 260-267. 

Abrahamsen MS, Templeton TJ, Enomoto S, Abrahante JE, Zhu G, Lancto CA, Deng M, Liu C, Widmer G, Tzipori S, Buck GA, Xu P, Bankier AT, Dear PH, Konfortov BA, Spriggs HF, Iyer L, Anantharaman V, Aravind L, Kapur V (2004) Complete genome sequence of the apicomplexan Cryptosporidium parvum. Science 304 441-445 Aji T, Flanigan T, Marshall R, Kaetzel C, Aikawa M (1991) Ultrastructural study of asexual development of Cryptosporidium parvum in a human intestinal cell line. J Protozool 38 82S... 

Now we might consider what is in fact the common clay mineralogy of sandstones. Shelton (1964), Bucke and Mankin (1971) find it to be most often dominated by kaolinite. This mineral although hydrous, is conspicuous by its lack of alkalis. Thus one could suspect that alkali activity in pore solutions of sandstones is, or was, frequently low, lower at any rate than adjacent mica-bearing shales. Laboratory studies by Hanshaw and Coplen (1973) and Khareka and Berry (1973) would give a plausible explanation for such a phenomenon. If solutions are forced hydrostatically across the argillaceous membrane, ionic species in solution are selectively... 

Wester RC, Maibach Hl, Bucks DA, et al. 1990. Percutaneous absorption and skin decontamination of PCBs In vitro studies with human skin and in vivo studies in the Rhesus monkey. J Toxicol Environ Health 31 235-246. 

Studies in flow-through diffusion cells showed that full-thickness rat skin absorbed [ Cjphenol at a slightly faster rate than human skin (Hotchkiss et al., 1992), which absorbs phenol reasonably well (Bucks et al., 1990). 

Cheetham, P. S. J., K. W. Blunt, and C. Bucke, "Physical Studies on Cell Immobilization Using Calcium Alginate Gels," Biotech. Bioeng. 21 (1979) 2155-2168. 

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