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171.
S. T. Chapman P. A. García-Sánchez D. Llena V. Ponomarenko J. C. Rosales 《manuscripta mathematica》2006,120(3):253-264
Problems involving chains of irreducible factorizations in atomic integral domains and monoids have been the focus of much recent literature. If S is a commutative cancellative atomic monoid, then the catenary degree of S (denoted c(S)) and the tame degree of S (denoted t(S)) are combinatorial invariants of S which describe the behavior of chains of factorizations. In this note, we describe methods to compute both c(S) and t(S) when M is a finitely generated commutative cancellative monoid. 相似文献
172.
William R. Adams John A. Zollweg William B. Strett Walter G. Chapman Paulette Clancy 《Fluid Phase Equilibria》1988,40(3):247-257
Measurements of the excess enthalpy of krypton and xenon mixtures at 163 K are reported. These results are found to disagree with the only other published result. This discrepancy is discussed. Conformal solution theory is used to provide an unbiased prediction of the excess enthalpy. We review published experimental and calculated excess thermodynamic properties of the Kr/Xe system at zero pressure and 161.38 K and 165 K. 相似文献
173.
D.M. Donnet J.N. Chapman H.W. van Kesteren W.B. Zeper 《Journal of magnetism and magnetic materials》1993,120(1-3):268-270
We have investigated thermomagnetically written marks in Co/Pt multilayers using the modified differential phase contrast mode of Lorentz microscopy. Images thus obtained allow the domain structure in individual marks to be studied with a resolution of 20 nm and can be analysed quantitatively for comparison with recording data. 相似文献
174.
D. Errede C. Akerlof J. Chapman N. Harnew P. Kesten S. Kooijman D.I. Meyer D. Nitz D. Rubin A.A. Seidl R. Thun T. Trinko M. Willutzky M. Derrick E. Fernandez R. Fries L. Hyman P. Kooijman J. VaVra 《Physics letters. [Part B]》1984,149(6):519-523
A search was made in 29 GeV e+e? annihilations for heavy, neutral leptons decaying to e±X?(ν), where X is a muon or charged meson. Six events with isolated e±X? pairs were found for an intergrated luminosity of 106 pb?1. The expected background is 5.5 ± 2.2 events. Limits on depend on mass and range from 8 to 20 × 10?5 nb. 相似文献
175.
Two cases of bilateral vocal fold immobility (VFI) after identification and preservation of the recurrent laryngeal nerves (RLNs) required tracheotomy until vocal fold recovery. The first patient underwent thyroid surgery without preoperative or postoperative evaluation of the vocal folds, administration of postoperative intravenous steroids, or electrophysiologic monitoring of the RLNs, whereas the second patient underwent a thyroid procedure in which all of the aforementioned were executed. Preoperative and postoperative clinical evaluation of the RLNs is strongly suggested in patients undergoing thyroid surgery, especially revision surgery. Patients potentially undergoing total thyroidectomy should be counseled about the remote chance of airway obstruction and should be properly selected for this operation. Subclinical stretching of the RLNs or ischemia from the endotracheal tube cuff can result in unilateral VFI, and rarely bilateral VFI, requiring reintubation, tracheotomy, or vocal fold lateralization. Electrophysiologic monitoring may not always predict bilateral VFI. 相似文献
176.
H. J. Jensen R. A. Bark R. Bengtsson G. B. Hagemann P. O. Tjøm S. Y. Araddad C. W. Beausang R. Chapman J. Copnell A. Fitzpatrick S. J. Freeman S. Leoni J. C. Lisle J. Simpson A. G. Smith D. M. Thompson S. J. Warburton J. Wrzesiński 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(2):127-132
Theπh9/2[541 1/2?] band in 167Tm has been studied through the 124Sn(48Ca, p4n)167Tm reaction at E beam = 210 MeV. The favoured signature of the πh9/2[541 1/2?] band is observed to spin 61/2h?. A remarkable small gain in aligned angular momentum at the AB-band crossing has been found. The crossing frequency and the gain in aligned angular momentum for 167Tm are compared with data for the N = 98 isotones of Lu, Ta and Re, and contrasted with Cranked Shell Model predictions, based on frequency diabatic configurations. Large deviations are found for the gain in aligned angular momentum. 相似文献
177.
Gomez-Cadenas JJ Heusch CA Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Golding L Green A 《Physical review letters》1991,67(8):1007-1010
178.
179.
180.
Robert S.L. Chapman Molly Francis Ruth Lawrence Joshua D. Tibbetts Steven D. Bull 《Tetrahedron》2018,74(44):6442-6452
Formyloxyacetoxyphenylmethane, symmetric 1,1-diacylals and mixed 1-pivaloxy-1-acyloxy-1-phenylmethanes have been used as moisture stable O-formylating and O-acylating reagents for primary and secondary alcohols, allylic alcohols and phenols under solvent/catalyst free conditions to afford their corresponding esters in good yield. 相似文献