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221.
Tomoyuki Mochida Kousuke Takazawa Michio M. Matsushita Tadashi Sugawara 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):m431-m433
In the title compound, (C16H36N)2[Co(C4N2S2)2]2, pairs of [Co(C4N2S2)2]? anions combine to form discrete crystallographically centrosymmetric dimers, which stack along the c axis, surrounded by the counter‐cations. The metal atom in the anion has a five‐coordinate distorted square‐pyramidal geometry. 相似文献
222.
Michio Zenki Kikuko Ohmuro Kyoji T?ei 《Fresenius' Journal of Analytical Chemistry》1990,338(6):707-709
Summary A spectrophotometric flow injection technique for the determination of calcium based on its color reaction with chlorophosphonazo III(CPA-III) is described. The complex formation of CPA-III with calcium ions was carried out in the presence of 0.01 mol/l oxalate at pH 2.8. Most of the common foreign ions did not interfere. Only strontium, barium and rare earth metals interfered. Under the optimum conditions, the calibration curve was linear up to 1.2 ppm calcium and the detection limit was 0.01 ppm for a sample volume of 120 l. The relative standard variations for 0.4 and 1.0 ppm calcium were 0.354 and 0.352%, respectively. The method was successfully applied to the determination of calcium in rain and snow. 相似文献
223.
Michio Jimbo 《Letters in Mathematical Physics》1986,11(3):247-252
We study for g=g[(N+1) the structure and representations of the algebra (g), a q-analogue of the universal enveloping algebra U(g). Applying the result, we construct trigonometric solutions of the Yang-Baxter equation associated with higher representations of g. 相似文献
224.
On the basis of the scale covariance of correlation functions under a coarsegraining in space and time, the Boltzmann equation for neutral gases, the Balescu-Lenard-Boltzmann-Landau equation for dilute plasmas, and linear equations for the variances of fluctuations are derived from the BBGKY hierarchy equations with no short-range correlations at the initial time. This is done by using Mori's scaling method in an extended form. Thus it is shown that the scale invariance of macroscopic features affords a useful principle in nonequilibrium statistical mechanics. It is also shown that there existtwo kinds of correlation functions, one describing the interlevel correlations of the kinetic level with its sublevels and the other representing the fluctuations in the kinetic level.Partially financed by the Scientific Research Fund of the Ministry of Education. 相似文献
225.
Miyazaki Y Inaba A Sorai M Taylor PS Lahti PM 《The journal of physical chemistry. B》2008,112(27):8144-8150
The heat capacity of the title organic free radical, PhBABI, was measured over 0.3-300 K by adiabatic calorimetry and relaxation methods in the presence of external magnetic fields up to 9 T. A hump in the magnetic heat capacity was observed with a maximum at about 15 K in zero field, which did not shift at fields up to 9 T. The experimental magnetic entropy was in good agreement with the theoretical value of R ln 2 (= 5.76 J K(-1) mol(-1)) for S = 1/2 systems. The higher temperature, field-insensitive feature was fitted to several antiferromagnetic Heisenberg models. The best fits were obtained using spin ladder and coupled spin bilayer models. 相似文献
226.
Wang Q Takeuchi A Yamamura Y Saito K Mori W Sorai M 《The journal of physical chemistry. B》2008,112(35):11039-11048
A pair of structural isomers was isolated at room temperature for the thermochromic nickel complex bis( N-isopropyl-5,6-benzosalicylideneiminato)nickel(II); one is a diamagnetic green form with square-planar coordination geometry (G phase), and the other is a paramagnetic brown form with a tetrahedral geometry (B phase). However, a question as to which form is thermodynamically stable was left open. To solve this problem, thermal and magnetic properties of this complex were investigated by adiabatic heat capacity calorimetry in the 6-508 K temperature range and magnetic measurements in the 2-400 K region. In addition to the two forms previously reported, two metastable crystal forms (G' and B' phases) were found. The stable phase sequence was G phase, B phase, and then liquid upon heating. The supercooled B phase gave rise to a small phase transition with nonmagnetic origin at around 50 K. By rapidly cooling the liquid, a glassy liquid state was realized below approximately 290 K. The order of thermodynamic stability at 298.15 K was revealed to be the G, B, G', and then the B' phase. The entropy, enthalpy, and Gibbs energy differences between the B and the G phases at 298.15 K were S degrees (B) - S degrees (G) = 32.8 J K (-1) mol (-1), H degrees (B) - H degrees (G) = 16.0 kJ mol (-1), and G degrees (B) - G degrees (G) = 6.25 kJ mol (-1), respectively. 相似文献
227.
Ng YH Ikeda S Harada T Sakata T Mori H Takaoka A Matsumura M 《Langmuir : the ACS journal of surfaces and colloids》2008,24(12):6307-6312
Platinum (Pt) nanoparticles encapsulated in microporous carbon with a hollow structure (nPt@hC) were fabricated on the basis of a titanium(IV) oxide (TiO2) photocatalytic reaction. From the tomogram of a sample studied by using a transmission electron microscope (TEM), the Pt nanoparticles were found to be embedded in the carbon shell and were physically separated from each other by the carbon matrix. Owing to this unique structure, the Pt particles showed high resistance to sintering when subjected to thermal treatment at temperatures up to 800 degrees C. As a result, hydrogenation reactions using various heat-treated nPt@hCs as catalysts indicated that loss of catalytic activity was minimized. Thus, the present system will be a promising system for optimizing catalyst nanostructures utilized in processes requiring rigorous conditions. 相似文献
228.
Hao G Qing-Hua Z Miao-Miao J Jin-Shan T Cheng-Du M Kui H Michio N Nai-Li W Xin-Sheng Y 《Magnetic resonance in chemistry : MRC》2008,46(12):1148-1152
A series of polyketide-originated metabolites (1-5) were isolated from a marine sponge-derived fungus Mycelia sterilia. Of these, 1-3 were new compounds. Their structures were elucidated by spectroscopic methods as (4R*, 5S*, 6S*, 8S*, 13R*)-1-(2,8-dihydroxy-1,2,6-trimethyl-1,2,6,7,8,8a-hexahydro-naphthalen-1-yl)-3-methoxy-propan-1-one (1), 4,8-dihydroxy-7-(2-hydroxy-ethyl)-6-methoxy-3,4-dihydro-2H-naphthalen-1-one (2) and 1-methyl-naphthalene-2,6-dicarboxylic acid (3). In 1, the proton-proton long-range coupling phenomenon claimed attention and was discussed. 相似文献
229.
Yamada M Someya C Wakahara T Tsuchiya T Maeda Y Akasaka T Yoza K Horn E Liu MT Mizorogi N Nagase S 《Journal of the American Chemical Society》2008,130(4):1171-1176
The photochemical reaction of M2@C80 (M = La and Ce) with 2-adamantane-2,3'-[3H]-diazirine (1) affords the corresponding adducts by carbene addition. The adducts were characterized by spectroscopic and single-crystal X-ray structure analyses. Crystallographic data for the adduct La2@C80(Ad) (2, Ad = adamantylidene) reveal that the two La atoms are collinear with the spiro carbon of the 6,6-open adduct. It is noteworthy that the La-La distance is highly elongated by the addition of carbene. Paramagnetic 13C NMR spectral analysis of the adduct Ce2@C80(Ad) (3) indicates that the two Ce atoms are also collinear with the spiro carbon at room temperature in solution. The unique metal positions were confirmed by density functional calculations. 相似文献
230.