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561.
Akiko Goto Hirokazu Fujimaki Toshiro Morikiyo Jianming Liu 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(6):269
We found a highly dolomitic lamprophyre diatreme at Badou, Shandong province, China for the first time. Although a number of silicate-rich carbonatite and glimmerite dikes and sheets were found around Badou, no alkaline rock–carbonatite plutonic complex exists nearby. Dolomitic lamprophyre diatreme that is not related with plutonic complex is not known yet either, and this is the first report of such an unusual occurrence. We report the whole-rock major and trace element chemistries of the lamprophyric rocks. The rocks consist of dominant dolomite with associated phlogopite, clinopyroxene, olivine, apatite and carry a number of xenoliths. Judging from all the geochemical and mineralogical data, the rock from Badou pipe should belong to the group of ultramafic lamprophyre and, more strictly, it should be called melnoite defined by Mitchell (1994).1) This finding should contribute to the understanding of the origin of carbonatite magma and the relationships between carbonatite and silicate magmas. 相似文献
562.
Tokuhiro Watanabe Ikuko Ueda Naomi Hayakawa Yasuo Kondo Hiroko Adachi Akiko Iwasaki Shizuko Kawamata Fumiko Mentori Miyuki Ichikawa Kayo Yuasa Akihiro Ohta Teruo Kurihara Hiroshi Miyamae 《Journal of heterocyclic chemistry》1990,27(3):711-716
2,3-Dichloro- and 2,5-dichloropyrazines were treated with sodium azide. The former gave diazidopyrazines and the latter, monoazidomonochloropyrazines. Pyrolysis of 2,3-diazidopyrazines resulted the production of 1,2-dicyanoiminoethanes and that of 2-azido-5-chloropyrazines, chloroimidazoles. 相似文献
563.
Keiko Ikoma Akiko Okami Tatsuo Arai Hirochika Sakuragi Katsumi Tokumaru 《Tetrahedron letters》1984,25(45):5161-5164
The photostationary isomer ratios and quantum yields for triplet sensitized isomerization of the four isomers of a conjugated imine, l-methoxyimino-3-phenyl-2-propene, were determined to explore the reaction mechanism. 相似文献
564.
565.
Mazzapioda Lucia Sgambetterra Mirko Tsurumaki Akiko Navarra Maria Assunta 《Journal of Solid State Electrochemistry》2022,26(1):17-27
Journal of Solid State Electrochemistry - A series of sulfated aluminum oxides (S-Al2O3), investigated as an electrolyte additive in Nafion membranes, was synthesized via three different methods:... 相似文献
566.
Tokuichiro Seki Kenji Yamaji Yoshimasa Orita Soyao Moriguchi Akiko Shinoda 《Journal of chromatography. A》1996,730(1-2):139-145
A column-switching liquid chromatographic method for the simultaneous determination of uric acid and creatinine in human serum and urine was developed. Creatinine and uric acid were separated by size-exclusion chromatography on a hydrophilic gel column (C1) and creatinine eluted from Cl was separated from proteins by filtration through a longer hydrophilic gel column (C2). The creatinine fraction eluted from C2 was transferred to a weakly acidic cation-exchange column (C3) and then to a strongly acidic cation-exchange column (C4). Uric acid eluted from Cl after creatinine was transferred to an anion-exchange column (C5) and then to a hydrophilic gel column (C6). The mobile phase was a mixed buffer of pH 5.1 (propionic acid-succinic acid-NaOH, 60:15:60 mmol/1 in water). Diluted serum and urine could be injected onto C1, and Cl was backflushed after the transfer of uric acid from Cl to C5.
Creatinine and uric acid in the eluate were determined by measuring their ultraviolet absorption at 234 and 290 nm, respectively. The recovery of uric acid and creatinine added to diluted serum (20-fold dilution, concentration 20 and 5 μmol/1, respectively) was 98.9±0.56% and 100.9±1.29%, respectively. The recovery of uric acid and creatinine added to diluted urine (100-fold dilution, concentration 50 and 100 μmol/l, respectively) was 99.4±0.72% and 98.7±1.45%, respectively (mean±R.S.D., n=6). 相似文献
567.
Sulfurization of β-dithiolactone (4) gave corresponding 1,2-dithiolane-3-thione (2a) via an ionic intermediate. Oxidation of β-dithiolactone 4 by m-CPBA afforded corresponding S-oxide (11), while dioxide (12) was obtained when 3 equiv of m-CPBA was used. Dithiolane-3-thione 2a reacted with ethylenebis(triphenylphosphine)platinum or tetrakis(triphenylphosphine)palladium to afford the corresponding dithiolato-platinum (20) and dithiolato-palladium (21) complexes in good yields. 相似文献
568.
Inagaki K Takatsu A Watanabe T Aoyagi Y Yarita T Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2007,387(7):2325-2334
A new marine sediment certified reference material, NMIJ CRM 7306-a, for butyltin and phenyltin analysis has been prepared
and certified by the National Metrological Institute of Japan at the National Institute of Advanced Industrial Science and
Technology (NMIJ/AIST). Candidate sediment material was collected at a bay near industrial activity in Japan. After air-drying,
sieving, and mixing the material was sterilized with γ-ray irradiation. The material was re-mixed and packaged into 250 glass
bottles (15 g each) and these were stored in a freezer at −30 °C. Certification was performed by use of three different types
of species-specific isotope-dilution mass spectrometry (SSID–MS)—SSID–GC–ICP–MS, SSID–GC–MS, and SSID–LC–ICP–MS, with 118Sn-enriched organotin compounds synthesized from 118Sn-enriched metal used as a spike. The 118Sn-enriched mono-butyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) were synthesized as a mixture whereas the 118Sn-enriched di-phenyltin (DPhT) and triphenyltin (TPhT) were synthesized individually. Four different extraction methods,
mechanical shaking, ultrasonic, microwave-assisted, and pressurized liquid extraction, were adopted to avoid possible analytical
bias caused by non-quantitative extraction and degradation or inter-conversion of analytes in sample preparations. Tropolone
was used as chelating agent in all the extraction methods. Certified values are given for TBT 44±3 μg kg−1 as Sn, DBT 51 ± 2 μg kg−1 as Sn, MBT 67 ± 3 μg kg−1 as Sn, TPhT 6.9 ± 1.2 μg kg−1 as Sn, and DPhT 3.4 ± 1.2 μg kg−1 as Sn. These levels are lower than in other sediment CRMs currently available for analysis of organotin compounds. 相似文献
569.
570.