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71.
G. Ponzano T. Regge E. R. Speer M. J. Westwater 《Communications in Mathematical Physics》1969,15(2):83-132
The monodromy rings of self-energy graphs, with two vertices and an arbitrary number of connecting lines, are determined.Research sponsored by the Air Force Office of Scientific Research, Office of Aerospace Research, United States Air Force, under AFOSR Grant 68-1365. 相似文献
72.
73.
Ferruccio Bertolini 《Tetrahedron letters》2006,47(1):61-64
A conceptually new regioselective and highly syn-stereoselective intermolecular Friedel-Crafts-type O-alkylation of phenols with aryl epoxides by the use of appropriately substituted aryl borates is reported. The carbon-carbon bond formation occurs in neutral and mild conditions without the need for external Lewis acids or transition metal catalysts. 相似文献
74.
Dr. Ferruccio v. Bacho 《Monatshefte für Chemie / Chemical Monthly》1916,37(2-3):119-123
Ohne Zusammenfassung 相似文献
75.
Ferruccio Casabuona Antonio Longo Angelo Crugnola Paolo Lombardi 《Tetrahedron letters》1981,22(41):4145-4148
The total synthesis of chiral “4,7-lactam” has been accomplished starting from 4-acetoxyazetidinone. An independent route from methyl penicillanate has been used to test the efficiency of the foregoing synthesis. 相似文献
76.
Ferruccio Colombini Enrico Jannelli Sergio Spagnolo 《Annali di Matematica Pura ed Applicata》1986,143(1):187-195
Summary We consider the solvability in the Mandelbrojt classes {Mh} (for the definition see (6), (7), (8), (9) below) of the Cauchy problem for hyperbolic equations of the type utt - - a(t) uxx=0, where a(t) is a strictly positive continuous function. More precisely, we give an example of a function a(t) for which the Cauchy problem is not well-posed in any class {Mh} containing a non-trivial function with compact support.This work is partially supported by G.N.A.F.A., C.N.R. and by Ministero P.I. 相似文献
77.
Creatinine in human serum was separated in a fused-silica capillary with H3PO4 (75 mmol/L, pH 2.5) as BGE, followed by UV detection at 200 nm. Serum with methylimidazole added as internal standard was deproteinized with acetonitrile and the supernatant, after dilution with water was injected at pressure mode. Creatinine and methylimidazole were baseline-resolved in 6.5 min. Linearity in the 0-880 micromol/L range gave an r2 > or = 0.998, recovery was 102 +/- 2.8% (n = 6). Enzymatic breakdown with creatininase confirmed that serum does not interfere. The within-day and between-days coefficient of variation (CV) were < or = 2.16 and 2.7%, respectively. The accuracy, determined for lyophilized samples by isotope dilution gas chromatography-mass spectrometry was < or = +/- 2.0%. The results were compared with HPLC for 32 lyophilized samples and on 27 serum pools. Capillary electrophoresis, rapid and inexpensive, seems a promising alternative to high-performance liquid chromatography (HPLC) for creatinine determination in human serum. 相似文献
78.
The development of a novel asymmetric ring opening of bi- and polycyclic hydrazines with aryl organometallic reagents is presented. The application of this reaction to the most simple bicyclic hydrazine 1a gives a straightforward regio- and diastereoselective access to synthetically useful trans 3,4-disubstituted hydrazinocyclopentenes in an enantioenriched form. 相似文献
79.
80.
Except for MEMS working in a ultra high vacuum, the main cause of damping is the air surrounding the system. When the working pressure is equal to the atmospheric one (from now on called “high pressure,” i.e., 105 Pa), the mean free path of an air molecule is much smaller than typical MEMS dimensions. Thus, air can be considered as a viscous fluid and two phenomena occur: flow damping and squeeze film damping. These two phenomena can be evaluated through a simplified Navier–Stokes equation. In a medium vacuum (from now on called “low pressure”), i.e., the “packaging” pressure, the air cannot be considered as a viscous fluid any more since the mean free path of an air molecule is of the same order of magnitude of typical MEMS dimensions. Thus, the molecular fluid theory must be used to estimate the damping. To predict the damping of a MEMS device both at high and low pressure levels, a multiphysics code was used. The proposed approach was validated through comparison with experimental data. 相似文献