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181.
An electro-optic (EO) coefficient can be evaluated from a modulated signal by applying an AC voltage to a plane-parallel sample
in an interferometer. We proposed a method for compensating multiple-reflection of a light in the sample. The multiple-reflection
causes errors in the evaluated EO coefficient. In measurement using a Mach-Zehnder interferometer, we analyzed the multiple-reflection
and clarified its unfavorable effect. The effect could be avoided simply by selecting the incidence angle of the light on
the sample. We confirmed this by measuring the EO coefficient of a KTiOPO4 crystal. 相似文献
182.
This paper deals with a prediction problem of a new targeting variable corresponding to a new explanatory variable given a training dataset. To predict the targeting variable, we consider a model tree, which is used to represent a conditional probabilistic structure of a targeting variable given an explanatory variable, and discuss statistical optimality for prediction based on the Bayes decision theory. The optimal prediction based on the Bayes decision theory is given by weighting all the model trees in the model tree candidate set, where the model tree candidate set is a set of model trees in which the true model tree is assumed to be included. Because the number of all the model trees in the model tree candidate set increases exponentially according to the maximum depth of model trees, the computational complexity of weighting them increases exponentially according to the maximum depth of model trees. To solve this issue, we introduce a notion of meta-tree and propose an algorithm called MTRF (Meta-Tree Random Forest) by using multiple meta-trees. Theoretical and experimental analyses of the MTRF show the superiority of the MTRF to previous decision tree-based algorithms. 相似文献
183.
184.
Yasuharu Yoshimi Shota Hayashi Keisuke Nishikawa Yoshiki Okita Kousuke Maeda Toshio Morita Tatsuya Itou 《Research on Chemical Intermediates》2013,39(1):397-402
Decarboxylative radical addition of N-(t-butoxycarbonyl)amino acids to acrylonitrile was achieved by excitation of 1,4-dicyanonaphthalene. The photochemical decarboxylation was highly dependent on the dicyanoarenes used as electron acceptors and on addition of a base. The photoreaction proceeded smoothly to yield the decarboxylative adduct even in the presence of only a catalytic amount of 1,4-dicyanonaphthalene. 相似文献
185.
Takeshi Saito Naoya Miura Akira Namera Shigenori Ota Shota Miyazaki Sadaki Inokuchi 《Chromatographia》2014,77(9-10):687-693
Clinical diagnosis of tetrodotoxin (TTX) poisoning can be difficult because of the lack of characteristic morphological findings and a screening test, such as an immunoassay. Here, we present a fully validated method for the analysis of TTX in serum and urine. In this method, serum and urine samples were extracted using MonoSpin CBA or amide columns, followed by LC–MS/MS analysis. The TTX was eluted from the column by 0.1 mL of 10 % acetic acid solution, and was directly injected into LC–MS/MS. An Agilent 1200 HPLC system equipped with a HILIC separation column (Zorbax HILIC Plus 2.1 × 100 mm, 3.5 μm) was used for isocratic elution, with a mobile phase of 10 mM ammonium formate with formic acid (95:5, v/v), along with 5 mM trifluoroacetic acid and 2 % acetonitrile. TTX was detected with an Agilent 6410 mass spectrometer utilizing positive electrospray ionization and multiple reaction monitoring. Limits of quantification for serum and urine were established to be 1 and 0.5 ng mL?1, respectively. Limits of detection for serum and urine were 0.5 and 0.25 ng mL?1, respectively. Intra-day and inter-day precision varied from 1.5 to 8.5 %. The recovery was >86.5 % for both matrices. In this method, the sample preparation process prior to injection into the LC–MS/MS takes approximately 10–15 min, which reduces the extraction time to one-tenth of that of previous methods. The application of this method was further verified by analysis of biological materials from a patient suffering from puffer fish poisoning. 相似文献
186.
187.
Tsubasa Inoue Takayo Moriuchi-Kawakami Kentaro Kuda Shota Matsubara Keiichi Fujimori Toshiyuki Moriuchi 《Tetrahedron》2019,75(15):2330-2335
C3-functionalized cyclotriguaiacylene (CTG) derivatives were employed in the development of highly selective recognition compounds due to their unique molecular structures. Here, a novel C3-functionalized CTG containing boronate (PPB-CTG) was synthesized and its molecular recognition ability for hydroxyanthraquinones was investigated by fluorescence spectroscopy. The addition of the synthesized PPB-CTG led to a large increase in the fluorescence intensity of only alizarin and not 1-hydroxyanthraquinone, 2-hydroxyanthraquinone nor quinizarin. It was, thus, suggested that the cyclotriveratrylene (CTV) structure plays an important role in the recognition ability toward alizarin since the mono-phenyl boronate compound (m-TPBAP) showed poor fluorescence properties toward alizarin. Moreover, it was found that the 1:1 mixture of PPB-CTG and alizarin was effective as a fluorescence-enhanced probe toward fluoride ions. 相似文献
188.
Johannes Diesel Daria Grosheva Shota Kodama Nicolai Cramer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(32):11160-11164
An enantioselective nickel(0)‐catalyzed C?H functionalization of indoles and pyrroles that does not require the typical Lewis basic directing groups is disclosed. The reaction provides access to valuable tetrahydropyridoindoles and tetrahydroindolizines in high yields and enantioselectivity under mild reaction conditions. The process is characterized by a clear endo‐cyclization preference to yield the sought‐after six‐membered‐ring products. Key for the success of the activation and selectivity in the cyclization was the development of a novel chiral SIPr carbene ligand analogue with very bulky flanking groups. 相似文献
189.
Thermal decomposition of copper complexes of 1-phenyl-3-methyl-4-acyl-5-pyrazolone in air atmosphere
Y. Akama 《Journal of Thermal Analysis and Calorimetry》1995,45(6):1501-1506
Copper complexes of some 1-phenyl-3-methyl-4-acyl-5-pyrazolones have been prepared. The complexes were characterized by elemental analyses and thermal analyses. It was shown that the melting points decrease linearly in increasing the molecular weight of the complexes. 相似文献
190.
The extraction of zinc and cadmium with a mixture of a 1-phenyl-3-methyl-4-acyl-5-pyrazolone and trioctylphosphine oxide (TOPO) in various solvents is described. The extraction constants for systems based on eight 4-acyl compounds (C3C18) are reported. The 1-phenyl-3-methyl-4-stearoyl-5-pyrazolone/benzene system is most effective for the mutual separation of zinc and cadmium at pH 4.5; 20 μg of zinc can be separated efficiently from 20 mg of cadmium. 相似文献