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111.
Toyoshima Atsushi Mitsukai Akina Tsukada Kazuaki Ooe Kazuhiro Haba Hiromitsu Komori Yukiko Murakami Masashi Kaneya Yusuke Sato Daisuke Asai Masato Sato Tetsuya K. Nagame Yuichiro 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):421-430
Journal of Radioanalytical and Nuclear Chemistry - We have studied extraction behavior of group-6 elements Mo and W to search for suitable conditions for an on-line extraction experiment of their... 相似文献
112.
Mariko Kitajima Satoko Ohara Noriyuki Kogure Dammrong Santiarworn Hiromitsu Takayama 《Tetrahedron》2013
Six new β-carboline-type indole alkaloid glycosides, ophiorrhisides A–F (1–6), were isolated from Ophiorrhiza trichocarpon (Rubiaceae) collected in Thailand. Ophiorrhisides A (1) and B (2) possess a lactam function in the C ring and a unique biose residue in the molecule. Ophiorrhiside F (6) has a highly oxidized C ring with a 1,2-dicarbonyl function at C-5 and C-6 positions as well as a double bond between C-3 and C-14. 相似文献
113.
Mayeen Uddin Khandaker Hiromitsu Haba Masashi Murakami Naohiko Otuka Hasan Abu Kassim 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):759-764
Activation cross-sections of natCu(d,x)62,65Zn,64Cu,60g+mCo,59Fe reactions were measured using a stacked foil activation technique combined with HPGe gamma-ray spectrometry up to the deuteron energy of 24 MeV. Measured data were critically compared with the available literature data and theoretical data extracted from the TENDL-2012 library, and found only partial agreements among them. Cross-sections of natCu(d,x)59Fe reactions are reported here for the first time in the energy region of 19–23 MeV. Measured cross-sections of the long-lived 65Zn, 60gCo and 59Fe radionuclides are significant for understanding the activation behaviour of copper, an essential structural material used in accelerator and nuclear industry. 相似文献
114.
Hayashi Y Pirozhkov AS Kando M Fukuda Y Faenov A Kawase K Pikuz T Nakamura T Kiriyama H Okada H Bulanov SV 《Optics letters》2011,36(9):1614-1616
The interaction between a 25 TW laser and Xe clusters at a peak intensity of 1 × 101? W/cm2 has been investigated. Xe K-shell x rays, whose energies are approximately 30 keV, were clearly observed with a hard x-ray CCD at 3.4 MPa. Moreover, we studied the yield of the Xe K-shell x rays by changing the pulse duration of the laser at a constant laser energy and found that the pulse duration of 40 fs is better than that of 300 fs for generating Xe K-shell x rays. 相似文献
115.
Five arsenic species, trimethylarsine oxide, dimethylarsenic acid, monomethylarsonic acid, arsenobetaine and sodium arsenite, in urine were analysed by inductively coupled plasma mass spectrometry with ion chromatography (IC ICP MS). Since the toxicities of different arsenic compounds are different, speciation of arsenic compounds is very important in the investigation of metabolisms. In this paper, we applied ion chromatography (IC) as a separation device and inductively coupled plasma mass spectrometry (ICP MS) as a detection device. For separation of the five arsenic compounds, an anion-exchange column and, as mobile phase, tartaric acid were used. The eluent from the IC column was introduced directly into the nebulizer of the ICP MS and analysed at 75 amu. Detection limits were from 4 to 9 pg as arsenic. 相似文献
116.
The absolute configuration of pandamarilactonine-A, a pyrrolidine alkaloid, was established on the basis of total synthesis starting from l-prolinol. An insight into the mechanism of the low enantiomeric purity of natural pandamarilactonine-A is discussed. 相似文献
117.
Sigeru Torii Kenji Uneyama Michio Ono Hiromitsu Tazawa Setsuo Matsunami 《Tetrahedron letters》1979,20(48):4661-4662
A regioselective ω-epoxidation of polyisoprenoids has been realized by the sodium bromide promoted electrochemical oxidation in a mixed solvent (MeCN-THF-H2O). 相似文献
118.
Single-step sol–gel deposition was attempted for realizing submicron thick, (001) oriented Pb(Zr0.53Ti0.47)O3 (PZT) thin films, using an alkoxide solution containing polyvinylpyrrolidone (PVP). A solution of molar composition, Pb(NO3)2:Zr(OC3H7
n)4:Ti(OC3H7
i)4:PVP:H2O:CH3COCH2COCH3:CH3OC2H4OH:C3H7
nOH = 1.1:0.53:0.47:0.5:5:0.5:22:0.98, was prepared as a coating solution. Gel films were prepared on Pt(111)/TiO2/SiO2/Si(100) substrates by spin-coating, and calcined at 350 °C and annealed at 650 °C either in an electric furnace or in a near-infrared
(IR) furnace. When calcined in the near-IR furnace, the films became (001) oriented on annealing. When calcined in the electric
furnace, on the other hand, the films became randomly oriented on annealing. These observations indicate that the heating
the gel films from the substrate side in the calcination step at 350 °C induces crystallographic orientation in the annealing
step at 650 °C. The effects of the heating methods on the thermal decomposition of the gel films, and the microstructure and
dielectric properties of the fired films were studied. Finally 0.4 μm thick, (001) oriented PZT films could be successfully
prepared by non-repetitive, single-step deposition. The oriented film thus obtained had the remnant polarization 2P
r of 39 μC/cm2 and the dielectric constant ε′ of 960 ± 169. 相似文献
119.
Maeda H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(36):11274-11282
Supramolecular gels that change their state or structure in response to anion stimuli have been highlighted. Only a few examples exist of such supramolecular gels, the structures and properties of which can be controlled and modulated by interactions with anions. To form anion-responsive dimensionally-controlled organized structures, the constituent low-molecular-weight gelator molecules must act as anion receptors by possessing one or more of van der Waals interaction units (aliphatic chains), stacking pi planes, hydrogen-bonding sites, and metal-coordination units. This Concept focuses on the gelation and transition behaviors of amide- and urea-based anion-stimulated systems, metal-coordinated systems, and novel acyclic pi-conjugated oligopyrroles that act as "molecular flippers." 相似文献
120.
Selective iodination at the alpha-pyrrole positions of dipyrrolyldiketone BF(2) complexes is a key procedure to afford mono- and bisiodinated derivatives as the starting materials of the coupling reactions for various utility molecules and covalently linked oligomer systems. Iodination can also be applied to the phenylene-bridging receptor dimer to obtain the derivatives selectively iodinated at the terminal alpha-pyrrole position(s). 相似文献