Obraz Hindenburga O/S w twórczości Wernera Heiduczka

Correlated cosmogenic W and Os isotopic variations in Carbo and implications for Hf–W chronology

An obstacle for establishing the chronology of iron meteorite formation using Hf–W systematics (t1/2 = 8.9 Myr) is to find proper neutron fluence monitors to correct for cosmic ray modification of W isotopic composition. Recent studies showed that siderophile elements such as Pt and Os could serve such a purpose. To test and calibrate these neutron dosimeters, the isotopic compositions of W and...

Coupled W–Os–Pt isotope systematics in IVB iron meteorites: In situ neutron dosimetry for W isotope chronology

Tungsten isotope compositions of magmatic iron meteorites yield ages of differentiation that are within 72 Ma of the formation of CAIs, with the exception of IVB irons that plot to systematically less radiogenic compositions yielding erroneously old ages. Secondary neutron capture due to galactic cosmic ray (GCR) irradiation is known to lower the eW of iron meteorites, adequate correction of wh...

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OS Kernel

The basic virtual memory-mapped communication (VMMC) model provides protected, direct communication between the sender's and receiver's virtual address spaces, but it does not support high-level connection-oriented communication APIs well. This paper presents VMMC-2, an extension to the basic VMMC. We describe the design, implementation , and evaluate the performance of three mechanisms in VMMC...

OS Virtualization