Equations of state of matter from shock wave experiments

An interpretation of the shock wave Hugoniot relation is made by using the Mie-Grüneisen equation of state. Isothermal pressure-volume curves for various metals are calculated from the data of McQueen and Marsh and Al'tshuler et al. A linear relation between shock wave velocity us and particle velocity up is assumed, and the numerical integration is extended beyond the range of the experiments. Independent calculations are made by using either the Slater or the Dugdale-MacDonald formula. Results thus obtained do not differ appreciably. The result for iron is in good agreement with that obtained by Al'tshuler et al., who used an experimentally determined value of the Grüneisen ratio. The equations of state thus calculated are well approximated by the Murnaghan-Birch equation of state with the second-order coefficient ξ varying from −½ to ½. The use of the TFD model is not valid below 100 Mb. However, inspection of the results gives the impression that for some metal the P-p curve will approach the TFD curve at pressures higher than 100 Mb. The density and incompressibility of the earth's core are compared with those of iron. The general conclusion is that the density of the earth's core is about 1 to 1.5 g/cm^3 less than the density of iron at corresponding pressure and temperature. The difference in incompressibility is very small. Bullen's incompressibility-pressure hypothesis is tested on the basis of the result obtained here. The variation of the values of incompressibility among the metals studied here is too large even at the pressure of 4 Mb to support the hypothesis. A detailed inspection of the result for the in-compressibility obtained here, however, implies that it is still difficult to avoid the conclusion arrived at from the incompressibility-pressure hypothesis that the inner core is solid

Note on the variational and homogeneous layer approximations for the computation of Rayleigh-wave dispersion

An earlier study of upper mantle structure using a variational method is repeated using the homogeneous layer approximation programmed for an electronic digital computer to obtain dispersion curves. The dispersion curves computed by the two methods differ significantly but systematically so as to yield the same conclusion about the presence of the Gutenberg low-velocity zone in the upper mantle

Metastatic carcinoma of the colon similar to Crohn's disease: a case report.

A 68-year-old Japanese man with a history of linitis plastica carcinoma of the stomach and subsequent gastrectomy 8 years previously presented with lower abdominal pain. Radiological and endoscopic examinations showed multiple submucosal nodular lesions similar to Crohn's disease in the ileocecal area. A firm diagnosis could not be made after initial multiple biopsies. Finally, a submucosal biopsy revealed adenocarcinoma. The ileocecal lesion was diagnosed as a recurrence because of the histological findings, which included mucosal preservation, a similarity with the histologic type of stomach carcinoma, and atypical immunoreactivity for primary colon carcinoma; the lesion was negative for both cytokeratin 7 and cytokeratin 20. In cases where metastatic carcinoma of the colon is suspected, we recommend early consideration of a submucosal biopsy.</p

Absence of spectral peaks in short-period oscillations from the Chilean Earthquake

On the occasion of the great Chilean earthquake of May 1960, various modes of free oscillations of the earth were observed: spheroidal oscillations of wave number n = 2 (period 53 min) to 38 (3.7 min) [Benioff et al., 1961; Ness et al., 1961; Alsop et al., 1961; Bogert, 1961] and torsional oscillations of n up to 24 (5.2 min) [Bolt and Marussi, 1962; Brune et al., 1961]. From a rather negative result that the shorter-period oscillations were not well observed, we try here to deduce some conclusions regarding the earth's upper mantle structure or the oscillation mechanism of the earthquake. The result may be due to horizontal inhomogeneities of the upper mantle of the earth making the resolution of spectral peaks in shorter-period oscillations difficult, or it may be due to weak excitation of shorter-period oscillations by the source

PREPARATION OF 5H,7H-DIBENZ[c,e]OXEPIN-5-ONE DERIVATIVE THROUGH RECONSTRUCTION OF THE LACTONE RING

The systematic investigation of the efficient transformation of 6H-dibenzo[b,d]pyran-6-one into 5H,7H-dibenz[c,e]oxepin-5-one is described

X-Ray Fluctuations from Locally Unstable Advection-Dominated Disks

The response of advection-dominated accretion disks to local disturbances is examined by one-dimensional numerical simulations. It is generally believed that advection-dominated disks are thermally stable. We, however, find that any disurbance added onto accretion flow at large radii does not decay so rapidly that it can move inward with roughly the free-fall velocity. Although disturbances continue to be present, the global disk structure will not be modified largely. This can account for persistent hard X-ray emission with substantial variations observed in active galactic nuclei and stellar black hole candidates during the hard state. Moreover, when the disturbance reaches the innermost parts, an acoustic wave emerges, propagating outward as a shock wave. The resultant light variation is roughly (time) symmetric and is quite reminiscent of the observed X-ray shots of Cygnus X-1.Comment: plain TeX, 11 pages, without figures; to be published in ApJ Lette

SYNTHESIS OF ZANTHOXYLINE AND ITS RELATED COMPOUNDS: REVISION OF THE REPORTED STRUCTURE

Benzo[c]phenanthridine alkaloid, zanthoxyline, was synthesized through an intramolecular biaryl coupling reaction of N-naphthylbenzamide derivative using a palladium reagent. Comparison of the NMR data for the synthetic product with that reported previously revealed that the proposed structure was incorrect. Synthesis of the related compounds suggested that the correct structure of zanthoxyline is the previously known decarine