47 research outputs found

    Synthesis, Crystal Structures, Electronic Spectra, and Magnetic Properties of Thiolato-Bridged Trinuclear Cobalt(II) Complexes with N, N, S-Tridentate Thiolate Ligands

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    New trinuclear CoII complexes, [{Co(apaet)2}2Co]X2 (apaet– = 2-[(3-aminopropyl)amino]ethanethiolato; X = SCN (1), ClO4 (2), NO3 (3), Cl (4), Br (5), I (6)) and [{Co(apampt)2}2Co]X2 (apampt– = 1-[(3-aminopropyl)amino]-2-methylpropane-2-thiolato; X = NO3(7), ClO4 (8), Cl (9), Br (10), I (11)), and mononuclear CoIII complexes, [Co(apaet)2]X (X = ClO4 (12), NO3 (13)), were synthesized. Single-crystal X-ray crystallography of 1 and 7 confirmed that the trinuclear complexes have a linear arrangement of octahedral CoIIS2N4-tetrahedral CoIIS4-octahedral CoIIS2N4 chromophores where two thiolate ligands are coordinated to each terminal Co atom in a mer coordination mode and the two thiolato S atoms are further bound to the central Co atom, which is consistent with the electronic spectra and antiferromagnetic propertie

    Geometrical Isomerism in Ru2Au Heterometal Assembly: Cis-Linking of Tetracyanidoaurate to Tetrakis(Μ-Butanoato)Diruthenium

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    A heterometal assembled complex of tetrakis(μ-butanoato)diruthenium(II,III) and tetracyanidoaurate(III) [RuIIRuIII(n-C3H7COO)4AuIII(CN)4]n was synthesized and characterized by the elemental analysis and infrared spectroscopy. The single-crystal X-ray structure analysis revealed that the complex consists of zigzag chain molecules of alternating arrangement of the Ru2(n-C3H7COO)4+ and Au(CN)4– units with cis-bridging mode of the Au(CN)4– units. The temperature dependence of the magnetic susceptibility data (4.5—300 K) showed that the magnetic interaction between the dinuclear RuIIRuIII units (S= 3/2) is negligibly small with a zero-field splitting parameter D value of 60 cm-1

    Background Factors Affecting Visual Acuity at Initial Visit in Eyes with Central Retinal Vein Occlusion : Multicenter Study in Japan

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    Purpose: To determine the baseline characteristics of patients with central retinal vein occlusion (CRVO) that were significantly associated with the best-corrected visual acuity (BCVA) at the initial examination. Methods: This was a retrospective multicenter study using the medical records registered in 17 ophthalmological institutions in Japan. Patients with untreated CRVO (≥20-years-of-age) who were initially examined between January 2013 and December 2017 were studied. The patients’ baseline factors that were significantly associated with the BCVA at the initial examination were determined by univariate and multivariate linear regression analyses. Results: Data from 517 eyes of 517 patients were analyzed. Univariate analyses showed that an older age (r = 0.194, p < 0.001) and the right eye (r = −0.103, p < 0.019) were significantly associated with poorer BCVA at the initial visit. Multivariate analyses also showed that an older age (β = 0.191, p < 0.001) and the right eye (β = −0.089, p = 0.041) were significantly associated with poorer BCVA at the initial visit. Conclusions: The results indicate that an older age, a known strong factor, and the right eye were significantly associated with poorer BCVA at the initial visit to the hospital. These results suggest that functional and/or anatomical differences between the right and left eyes may be involved in these results

    Petrogenesis of Granitic Rocks in the Hisakajima Island, Goto Archipelago, Southwestern Japan: A Geochemical Study

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    Whole-rock chemical compositions including rare earth elements for the granitic rocks from the Hisakajima Island, Goto Archipelago, southwestern Japan were measured in order to constrain their origin and petrogenesis. The granites were divided into two types—a granodioritic group (GD) and a high Fe/Mg ratio granitic group (HFG). The granitic magma was formed by the upwelling of high-temperature mantle material, which might be related to the extension of the Japan Sea around the Middle Miocene. The origin of the GD magma was attributed to the mantle material, while the origin of the HFG magma was attributed to partial melting of the crust by upwelling of the high-temperature mantle. The amount of rare earth elements revealed the secondary addition of light rare earth elements through hydrothermal processes for the granites. Chondrite normalized rare earth element patterns revealed that the HFG rocks were not well differentiated

    Petrogenesis of Granitic Rocks in the Hisakajima Island, Goto Archipelago, Southwestern Japan: A Geochemical Study

    No full text
    Whole-rock chemical compositions including rare earth elements for the granitic rocks from the Hisakajima Island, Goto Archipelago, southwestern Japan were measured in order to constrain their origin and petrogenesis. The granites were divided into two types—a granodioritic group (GD) and a high Fe/Mg ratio granitic group (HFG). The granitic magma was formed by the upwelling of high-temperature mantle material, which might be related to the extension of the Japan Sea around the Middle Miocene. The origin of the GD magma was attributed to the mantle material, while the origin of the HFG magma was attributed to partial melting of the crust by upwelling of the high-temperature mantle. The amount of rare earth elements revealed the secondary addition of light rare earth elements through hydrothermal processes for the granites. Chondrite normalized rare earth element patterns revealed that the HFG rocks were not well differentiated

    Estimating Magma Crystallization Temperatures Using High Field Strength Elements in Igneous Rocks

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    Indirect calculation of magma crystallization temperatures is an important subject for geologists to know the petrogenesis of igneous rocks. During magma evolution from generation to crystallization, several processes control the behavior of elements. In this research, we obtained two new methods for the thermometry of magma by using high field strength elements (HFSEs; Zr, Hf, Ce, Y, and Ti) abundances in igneous rocks. The first was T(K) = −15,993/(lnCZr + lnCHf − 21.668), where CZr and CHf are the bulk-rock Zr and Hf contents in ppm, and T is the temperature in Kelvin. This equation was specially formulated to address metaluminous to peraluminous rocks with M 2 > 63 wt.%. The second was T(K) = −20,914/(ln(CHf + CY + CCe) + (ln(CZr/TiO2) − 31.153). CHf, CY, and CCe, and CZr are Hf, Y, Ce, and Zr contents (ppm) in the whole rocks. The second equation is more suitable for peralkaline to alkaline rocks with M > 2 and a wide range of SiO2. Both equations are applicable for temperatures from 750 °C to 1400 °C. These two equations are simple and robust thermometry methods and predict similar values in the range of TZr thermometry, which has previously been suggested for magma crystallization temperature

    Estimating Magma Crystallization Temperatures Using High Field Strength Elements in Igneous Rocks

    No full text
    Indirect calculation of magma crystallization temperatures is an important subject for geologists to know the petrogenesis of igneous rocks. During magma evolution from generation to crystallization, several processes control the behavior of elements. In this research, we obtained two new methods for the thermometry of magma by using high field strength elements (HFSEs; Zr, Hf, Ce, Y, and Ti) abundances in igneous rocks. The first was T(K) = &minus;15,993/(lnCZr + lnCHf &minus; 21.668), where CZr and CHf are the bulk-rock Zr and Hf contents in ppm, and T is the temperature in Kelvin. This equation was specially formulated to address metaluminous to peraluminous rocks with M &lt; 2 [(Na + K + 2Ca)/(Al &times; Si)] (cation ratio) and SiO2 &gt; 63 wt.%. The second was T(K) = &minus;20,914/(ln(CHf + CY + CCe) + (ln(CZr/TiO2) &minus; 31.153). CHf, CY, and CCe, and CZr are Hf, Y, Ce, and Zr contents (ppm) in the whole rocks. The second equation is more suitable for peralkaline to alkaline rocks with M &gt; 2 and a wide range of SiO2. Both equations are applicable for temperatures from 750 &deg;C to 1400 &deg;C. These two equations are simple and robust thermometry methods and predict similar values in the range of TZr thermometry, which has previously been suggested for magma crystallization temperature
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