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Understanding the material transport and mixing processes in the Solar protoplanetary disk provides important constraints on the origin of chemical and isotopic diversities of our planets. The limited extent of radial transport and mixing between the inner and outer Solar System has been suggested based on a fundamental isotopic dichotomy between non‐carbonaceous (NC) and carbonaceous (CC) meteorite groups. The limited transport and mixing could be further tested by tracing the formation regions of individual meteoritic components, such as Ca‐Al‐rich inclusions (CAIs) and chondrules. Here, we show further evidence for the outward transport of CAIs and chondrules from the inner and subsequent thermal processing in the outer region of the protoplanetary disk based on the petrography and combined Cr‐Ti‐O isotope systematics of chondrules from the Vigarano‐like (CV) carbonaceous chondrite Allende. One chondrule studied consists of an olivine core that exhibits NC‐like Ti and O, but CC‐like Cr isotopic signatures, which is enclosed by a pyroxene igneous rim with CC‐like O isotope ratios. These observations indicate that the olivine core formed in the inner Solar System. The olivine core then migrated into the outer Solar System and experienced nebular thermal processing that generated the pyroxene igneous rim. The nebular thermal processing would result in Cr isotope exchange between the olivine core and CC‐like materials, but secondary alteration effects on the parent body are also responsible for the CC‐like Cr isotope signature. By combining previously reported Cr‐Ti‐O isotope systematics of CV chondrules, we show that some CV chondrules larger than ~1 mm would have formed in the inner Solar System. The accretion of the millimeter‐sized, inner Solar System solids onto the CV carbonaceous chondrite parent body would require their very early migration into the outer Solar System within the first 1 million years after the Solar System formation. [ABSTRACT FROM AUTHOR]

As each country has its own rules of the society based on its own history and culture, introduction of new accounting standards will have different effect among countries. IFRS 2 Share-based Payment affected accounting standards in Malaysia and Japan. FRS 2 in Malaysia and ASBJ Statement 8 in Japan both adopted modified grant date fair value accounting for stock options. But the situation of stock option plans, not only before, but also after the adoption of modified grant date fair value accounting, are different between Malaysia and Japan. In Malaysia, although the culture is different from the USA, similar reaction was observed. In Japan, different reaction, namely, shift toward restricted stock type stock option plan was observed. In this paper, history of accounting, taxation, and law are compared and analyzed to clarify that the difference of the rules in each society affects the outcome of new accounting standards., INTRODUCTION In the USA, Baker (1940) analyzed the stock options used as a form of executive compensation in late 1920s to 1930s. As for accounting treatment for employee stock options, [...]

A sequential chemical separation technique for Cr, Fe, Ni, Zn, and Cu in terrestrial and extraterrestrial silicate rocks was developed for precise and accurate determination of elemental concentration by the isotope dilution method (ID). The technique uses a combination of cation-anion exchange chromatography and Eichrom nickel specific resin. The method was tested using a variety of matrixes including bulk meteorite (Allende), terrestrial peridotite (JP-1), and basalt (JB-lb). Concentrations of each element was determined by thermal ionization mass spectrometry (TIMS) using W filaments and a Si-B-AI type activator for Cr, Fe, Ni, and Zn and a Re filament and silicic acid-H3PO4 activator for Cu. The method can be used to precisely determine the concentrations of these elements in very small silicate samples, including meteorites, geochemical reference samples, and mineral standards for microprobe analysis. Furthermore, the Cr mass spectrometry procedure developed in this study can be extended to determine the isotopic ratios of [sup.53]Cr/[sup.52]Cr and [sup.54]Cr/[sup.52]Cr with precision of ~0.05[epsilon] and ~0.10[epsilon] (1[epsilon] = 0.01%), respectively, enabling cosmochemical applications such as high precision Mn-Cr chronology and investigation of nucleosynthetic isotopic anomalies in meteorites. 10.1021/ac901762a

Recent studies showed the potential of stable isotopes of the macronutrient calcium (δ44/40Ca) and nonessential strontium (δ88/86Sr) as new trophic level indicators in terrestrial vertebrates and marine teleost fishes. In this study, we tested whether similar Ca and Sr isotopic fractionation trends existed in macroinvertebrate‐dominated stream food webs compared to vertebrates despite their physiological differences. We have determined the δ44/40Ca and δ88/86Sr values as well as the 87Sr/86Sr ratios of stream macroinvertebrates and small gobies and their potential metal sources (stream water, periphyton, and terrestrial plant litter) in upper and lower reaches of two streams in the Lake Biwa catchment, central Japan. The 87Sr/86Sr ratios revealed that stonefly nymphs, crustacea, and gobies mostly relied on aquatic Sr sources. Higher 87Sr/86Sr ratios of some crane fly and caddisfly larvae, mayfly, dobsonfly, and dragonfly nymphs indicated greater terrestrial contributions via plant litter. Positive correlations between the δ44/40Ca and δ88/86Sr values implied that similar Ca and Sr sources existed, and that Ca and Sr stable isotopes underwent similar fractionation trends although Sr was not essential. The δ44/40Ca and partly the δ88/86Sr values were positively correlated with Sr/Ca ratios and negatively with δ15N values indicating trophic effects on Ca and Sr stable isotopes. The enrichment of 44Ca and 88Sr in large filter‐feeding caddisfly larvae was a notable exception from these trophic trends. Our data confirm that the trophic 44Ca and 88Sr depletion observed for marine teleost fishes and terrestrial vertebrates also applied to macroinvertebrate‐dominated stream food webs despite their different physiologies indicating that shared mechanisms of Ca and Sr isotopic fractionation may exist at the cellular or molecular level between these taxa. [ABSTRACT FROM AUTHOR]

Combined determination of Cr and Ti isotopes of planetary materials offers a means with which to investigate their genetic relationship and the evolution of the protoplanetary disk. Here, we report the new sequential chemical separation procedure for combined Cr and Ti isotope ratio measurements. It comprises three steps: (a) Fe removal using AG1‐X8 anion exchange resin, (b) Ti separation using TODGA resin and (c) Cr separation using AG50W‐X8 cation exchange resin (with one additional step of Ti purification using AG1‐X8 anion exchange resin for samples having high Cr/Ti and Ca/Ti ratios). We applied the proposed procedure to terrestrial and meteorite samples with various compositions. Typical recovery rates of 90–100% were achieved with total procedural Cr and Ti blanks of 3–5 and 2–3 ng, respectively. We measured the Cr and Ti isotope compositions of the separated samples using thermal ionisation mass spectrometry and multiple collector‐inductively coupled plasma‐mass spectrometry, respectively. Our Cr and Ti isotope data were found to be consistent with those of previous studies of individual Cr and Ti isotopic compositions of the meteorites. These results demonstrate the capability of our separation method when applied to combined high‐precision Cr and Ti isotope analyses for single digests of planetary materials. Key Points: Sequential chemical separation for combined Cr and Ti isotope ratio measurements has been developed. Our new method enables isotope analyses of 3 μg of Cr and 1.5 μg of Ti. The combined isotope analyses of primitive meteorite components will facilitate understanding of the evolution of the proto‐planetary disk. [ABSTRACT FROM AUTHOR]

Analyzes the diverse supernova sources of pre-solar material inferred from molybdenum isotopes in meteorites. Identification of some sources of pre-solar material; Elemental analysis of metal-poor stars; Emergence of diverse sources inferred from short-lived isotopes in the early Solar System.

Abstract: A new determination method for Cr, Mn, Fe, Co and Ni in silicate samples by an isotope dilution–internal standardization method (ID–IS)–high resolution (HR)–MC–ICP–MS has been developed. A silicate sample is dissolved into solution, and a Cr-spike solution is added into an aliquot of the sample solution. Then the solution is introduced into HR–MC–ICP–MS without chemical separation. Concentration of Cr is determined by ID, and those of Mn, Fe, Co and Ni are by ID–IS. Matrix effects were examined in detail, and negligible down to a dilution factor (DF; the weight of the sample solution over that of the sample in the solution) of ∼3000 for basalt, and ∼104 for peridotite and chondrite within an error range of ±1%. ID–IS–HR–MC–ICP–MS showed intermediate precision of ∼1% for basalt and chondrite, which is comparable to ID–TIMS for Cr, Fe and Ni, and >10 times better than HR–ICP–MS, suggesting that this method is suitable for precise Mn–Cr and Fe–Ni chronometers. [Copyright &y& Elsevier]