We have used an automated Millikan oil drop method to search for free fractional-charge particles in a sample containing in total 3.9 mg of pulverized Allende meteorite suspended in 259 mg of mineral oil. The average diameter of the drops was 26.5 microm with the charge on about 42 500 000 drops being measured. This search was motivated by the speculation that isolatable, fractional-charge part...

Xenon in the Presolar Diamonds: The finest grains of nanodiamonds identified in the carbonaceous and nonequilibrium ordinary chondrites are the most abundant relic grains, for which, as well as for the silicon carbide and graphite, the presolar origin is assumed [1].They could be apparently formed by condensation in cool stellar atmospheres or in the extreme PT-conditions of reprocessing the ma...

Introduction: The insoluble organic matter (IOM) contained with in all chondritic meteorites constitutes a significant reservoir of extraterrestrial organic matter that in some cases may be as high as 3.5 wt. % [1]. Whereas considerable effort has been made to develop a molecular understanding of meteoritic IOM, there remains considerable uncertainty regarding its origins, i.e., was IOM formed ...

A study of the frequency of meteorite falls in areas which have been highly populated throughout the last century indicates that the average rate of fall of meteorites on the earth probably lies between 0.32 and 1.0 falls/year 10 • km •. The frequency of fall as a function of type and mass has been studied, and it is shown that the distribution curves for stones and irons have similar shapes. T...

The NanoSIMS ion probe is a new-generation SIMS instrument, characterised by superior spatial resolution, high sensitivity and multi-collection capability. Isotope studies of certain elements can be conducted with 50–100 nm resolution, making the NanoSIMS an indispensable tool in many research fields. We review technical aspects of the NanoSIMS ion probe and present examples of applications in ...

during the course of our studies on archaeometallurgy in southeastern iran, we tried to survey the triangle of the sirdjān, neiriz and shahr- e- bābak. as a result, remains of old iron mining residues of smelting furnaces, and iron smelting slag heaps were observed and recorded. a few samples of iron ore and smelting slag have been analysed classically and instrumentally. according to the acq...

We report the results of abundance analyses of new samples of stars with planets and stars without detected planets. We employ these data to compare abundance–condensation temperature trends in both samples. We find that stars with planets have more negative trends. In addition, the more metal-rich stars with planets display the most negative trends. These results confirm and extend the finding...

Introduction: Methanogenic archaea, which consume CO2 and H2, have been considered models for possible life forms on Mars for a long time, even before the discovery of methane in the Martian atmosphere (1-8). Several intensive experimental studies have been conducted to investigate survivability of methanogens under conditions that approach those found on Mars (2, 3, 9). Various potential sourc...

have been analyzed for up to 40 major, minor, and trace elements. All data point to a clear distinction between these impact glasses and other tektites or impact glasses. e.g. from the Australasian strewn field. Halogens are generally enriched in the irghizites and zhamanshinites when compared to normal splash for tektites. with zhamanshinites enriched more than irghizites. The same holds also ...